Microbiology blog

Hepatitis C Virus

2010-08-24T12:22:22+01:00

Seng-Lai Tan and Yupeng He (Amgen Inc., Seattle, WA, USA and Antiviral Research, Abbott Laboratories, USA; respectively), present a new book on Hepatitis C: Antiviral Drug Discovery and Development
The editors of this book have recruited experts from around the world to produce a timely and well-compiled review of current HCV research with an emphasis on antiviral drug development. The chapters provide in-depth reviews of the most critical areas of research. Topics covered include: the HCV life cycle, HCV assays, HCV resources, HCV databases, HCV infection systems, models of hepatitis C infections, overview of the drug pipeline, clinical trial design, clinical virology and drug development, NS3 protease inhibitors, NS3-NS4A complex inhibitors, NS3 helicase inhibitors, NS4B targets and inhibitors, NS5A inhibitors, nucleoside inhibitors, NS5B polymerase inhibitors, glycoprotein-dependent entry, host cell targets and inhibitors, and innate immunity for HCV antiviral therapy.
An essential book for scientists involved with HCV and anyone interested in antiviral drug development. A recommended text for all virology libraries. read more ...

Hepatitis C: Antiviral Drug Discovery and Development

Edited by: Seng-Lai Tan and Yupeng He
ISBN: 978-1-904455-78-3
Publisher: Caister Academic Press
Publication Date: April 2011
Cover: hardback

Conference Alert: Environmental Virology

2010-08-19T12:08:30+01:00

October 7 - 9, 2010 Future Challenges in Food and Environmental Virology
Istanbul, Turkey Further information
2nd COST929 Symposium. A European Network for Environmental and Food Virology

Suggested reading: Environmental Microbiology Books

Conferencs Alert: Antivirals

2010-08-19T12:07:12+01:00

October 10 - 13, 2010 International Conference on Antivirals for Neglected and Emerging Viruses (ICAV-9)
Lubeck, Germany Further information
ICAV-9 will focus on the discovery of antiviral therapies of disease caused by dengue virus, influenza virus, enteroviruses, chikungunyavirus, coronaviruses, and other emerging or neglected viruses. Also have a microsymposium on Targeting Host Factors in HIV/AIDS Therapy

Suggested reading: Frontiers in Dengue Virus Research

Caliciviruses book review

2010-08-13T16:08:24+01:00

I am pleased to provide the following excerpt from a book review of Caliciviruses: Molecular and Cellular Virology:

"This book is an up-to-date review ... provides both basic information on the caliciviruses and the new experimental data ... The authors have provided important reviews of the current status of research ... a very comprehensive review" from Rebecca T. Horvat (University of Kansas Medical Center, USA) writing in Doodys read more ...

Caliciviruses: Molecular and Cellular Virology

Edited by: Grant S. Hansman, Xi Jason Jiang and Kim Y. Green
ISBN: 978-1-904455-63-9
Publisher: Caister Academic Press
Publication Date: April 2010
Cover: hardback

"a very comprehensive review" (Doodys)

Herpesviruses and Autophagy

2010-08-13T14:10:27+01:00

from Philipe A.M. Gobeil and David A. Leib writing in Alphaherpesviruses: Molecular Virology:

Autophagy is a rapidly growing area of biomedical research with broad relevance to fields including microbiology, cell biology, immunology, cancer biology, and neurodegeneration. In infection and immunity, it is emerging as a pivotal pathway mediating direct pathogen degradation as well as for the development of robust innate and adaptive immune responses. Successful pathogens have evolved to either evade or harness the autophagy pathway to further their replication and pathogenesis. In a recent review the basic aspects of autophagy will be described, along with its role in cellular homeostasis, and the development of immunity. The primary focus is a survey of past and recent research defining the interplay of autophagy and the herpesviruses, with particular reference to immune evasion and pathogenesis.

Further reading: Alphaherpesviruses: Molecular Virology

Molecular Chaperones and Alphaherpesvirus Infection

2010-08-13T14:02:15+01:00

from Christine M. Livingston, Christos Kyratsous, Saul Silverstein and Sandra K. Weller writing in Alphaherpesviruses: Molecular Virology:

Molecular chaperone proteins have long been recognized to play diverse and important roles in the life cycles of viruses from bacteriophage to SV40 to herpesviruses. The alphaherpesviruses HSV-1 and VZV not only interact with and reorganize cellular chaperones and co-chaperones but alphaherpesviruses also encode their own molecular chaperones. Cellular chaperones such as Hsp70, Hsc70 and Hsp90 are required for efficient production of infectious virus in that they play essential roles in nuclear transport of viral proteins, protein quality control and maintenance of cellular homeostasis during viral infection. These findings raise the possibility that molecular chaperones could be utilized as effective targets for antiviral therapy. A recent review reviews the evidence that replication of the human alphaherpesviruses herpes simplex virus type 1 and 2 (HSV-1 and 2) and varicella zoster virus (VZV) requires the activities of cellular and viral molecular chaperones.

Further reading: Alphaherpesviruses: Molecular Virology

Subversion of Interferon Responses by Herpesviruses

2010-08-13T14:00:18+01:00

from Paul T. Sobol and Karen L. Mossman writing in Alphaherpesviruses: Molecular Virology:

Key to the innate immune response to alpha herpesvirus infection is the expression and secretion of type I interferons (IFNs). This family of cytokines bolsters a host offensive to invading pathogens by inducing IFN stimulated genes (ISGs). Not surprisingly, the evolutionary pressure faced by alpha herpesviruses to adapt to the type I IFN response has shaped alpha herpesvirus evolution at the very interface of the virus-host interaction. The cumulative effects of type I IFN expression on alpha herpesvirus replication in vitro and dissemination in vivo are discussed in a recent review, along with mechanisms employed by these viruses to subvert the type I IFN response. Alpha herpesviruses block type I IFN production, inhibit the effects of type I IFN signal transduction and suppress downstream IFN-dependent effector pathways with the aims of augmenting viral replication and dissemination.

Further reading: Alphaherpesviruses: Molecular Virology

Oncolytic HSV Vectors for Cancer Therapy

2010-08-13T13:57:59+01:00

from Samuel Rabkin writing in Alphaherpesviruses: Molecular Virology:

Oncolytic HSV (oHSV) virotherapy is a promising new strategy for cancer therapy, converting a human pathogen into a therapeutic agent. This takes advantage of the biology of HSV, by introducing genetic alterations that limit virus replication and cytotoxicity to transformed cancer cells while making the virus non-permissive in normal cells. HSV encodes a large number of genes that are non-essential for growth in tissue culture cells, but are nevertheless important for growth in post-mitotic cells and for interfering with intrinsic antiviral and innate immune responses. Many of the cellular pathways regulating growth and antiviral responses are disrupted in cancer cells, which means that viral gene products allowing replication in normal cells are not necessary in cancer cells. In considering the development of an infectious agent for human use, safety is a critical consideration. Therefore mutations targeting cancer cells must be combined with mutations in genes that play important roles in vivo; causing pathogenicity, spread through the nervous system and other organs, latency and reactivation, and adaptive immune responses. This review will focus more on the virological aspects of oHSV vectors and less on the cancer cell target, and describe the multiple strategies and genes involved in generating oHSV vectors. However, it is important to bear in mind that the effect of different HSV mutations will be highly dependent upon the physiology of the particular type of cancer cell and tumor, and that each oHSV vector will be more effective in some tumor types, so that it is unlikely that any one oHSV will be optimal for all types of cancer.

Further reading: Alphaherpesviruses: Molecular Virology

Neisseria book review

2010-08-13T12:35:56+01:00

I am pleased to provide the following excerpt from a book review of Neisseria: Molecular Mechanisms of Pathogenesis:

"an excellent, comprehensive and updated review ... The editors, both experienced in the Neisseria field, have recruited 43 contributors from five different countries. Many of these individuals are well-recognized experts, front-line researchers and/or key opinion leaders in their topics. They provide, evaluate and discuss detailed up-to-date understanding, the significance of different findings, theories, hypotheses and conclusions, and future directions in a research, clinical and public health perspective. The volume is valuable and timely ... Most chapters ... are excellent, comprehensive, important, updated, well-written, and contain many relevant references and informative figures/tables summarizing the key information ... the 'future trends' are valuably emphasized in most chapters. Some chapters even recommend good web resources for further reading ... the editors of the present volume have collated an impressive group of well-recognized experts that provide exceedingly interesting, comprehensive and up-to-date understanding regarding molecular mechanisms of pathogenesis in Neisseria, as well as an excellent bibliography for further reading. The volume is valuable, timely and can be highly recommended for researchers, microbiologists, molecular biologists, epidemiologists, clinicians, vaccine manufacturers and students, who are involved and/ or interested in any topic involving pathogenic Neisseria species." from Magnus Unemo (Orebro, Sweden) writing in Expert Rev. Anti Infect. Ther. (2010) 8: 871–875. read more ...

Neisseria: Molecular Mechanisms of Pathogenesis

Edited by: Caroline Genco and Lee Wetzler
ISBN: 978-1-904455-51-6
Publisher: Caister Academic Press
Publication Date: January 2010
Cover: hardback

"excellent, comprehensive ... valuable and timely ... highly recommended" (Expert Rev. Anti Infect. Ther.)

Retrovirus book review

2010-08-12T16:17:23+01:00

I am pleased to provide the following excerpt from a book review of Retroviruses: Molecular Biology, Genomics and Pathogenesis:

"recommendable for life science researchers and all students in biology wishing to learn more about this very interesting field of retrovirology" from Stefan Hockertz (Seelze) writing in Arzneimittelforschung (2010) 60:466-469 read more ...

Retroviruses: Molecular Biology, Genomics and Pathogenesis

Edited by: Reinhard Kurth and Norbert Bannert
ISBN: 978-1-904455-55-4
Publisher: Caister Academic Press
Publication Date: January 2010
Cover: hardback

"recommendable for life science researchers" (Arzneimittelforschung)

HSV-1 Latency LATs

2010-08-12T08:30:44+01:00

from David C. Bloom and Dacia L. Kwiatkowski writing in Alphaherpesviruses: Molecular Virology:

Herpes simplex virus type 1 (HSV-1) latency is characterized by the persistence of viral genomes as episomes in the nuclei of sensory neurons. During this period only one region of the genome is abundantly transcribed: the region encoding the latency-associated transcripts (LATs). The LAT domain is transcriptionally complex, and while the predominant species that accumulates during latency is a 2.0 kb stable intron, other RNA species are transcribed from this region of the genome, including a number of lytic or acute-phase transcripts. In addition, a number of microRNA (miRNA) and non-miRNA small RNAs have recently been mapped to the LAT region of the genome. HSV-1 recombinant viruses with deletions of the LAT promoter exhibit reactivation deficits in a number of animal models, and there is evidence that other LAT deletion mutants also possess altered establishment and virulence properties. The phenotypic complexity associated with this region, as well as evidence that the LATs may play a role in suppressing latent gene expression, suggests that the LAT locus may function as a regulator to modulate the transcription of key lytic and latent genes.

Further reading: Alphaherpesviruses: Molecular Virology

HSV-1 and the DNA Damage Response

2010-08-12T08:28:40+01:00

from Matthew D. Weitzman and Sandra K. Weller writing in Alphaherpesviruses: Molecular Virology:

The cellular DNA damage machinery responds to virus infection and the foreign genomes that accumulate in the nuclei of infected cells. Many DNA viruses have been shown to manipulate the cellular DNA damage response pathways in order to create environments conducive to their own replication. Some cellular factors are activated during infection while others are inactivated.

Further reading: Alphaherpesviruses: Molecular Virology

HSV-1 DNA Replication

2010-08-12T08:26:57+01:00

from Stacey A. Leisenfelder and Sandra K. Weller writing in Alphaherpesviruses: Molecular Virology:

The cis- and trans-acting elements required for DNA synthesis of Herpes Simplex Virus (HSV) have been identified, and genetic and biochemical analyses have provided important insights into how they work together to replicate the large double-stranded viral genome. Furthermore, viral enzymes involved in DNA replication have provided a rich store of useful targets for antiviral therapy against herpesviruses. Despite these advances, many questions remain unresolved concerning the overall mechanism of genome replication. For instance, it has long been recognized that the products of viral DNA replication are head-to-tail concatemers; however, it is not clear how these concatemers are generated. A recent review summarizes the known functions of viral replication proteins and explore the possibility that these viral proteins may function in combination with cellular proteins to produce concatemers suitable for packaging into preformed viral capsids.

Further reading: Alphaherpesviruses: Molecular Virology

Roles of ICP22 in HSV-1 Replication

2010-08-12T08:24:33+01:00

from Stephen A. Rice writing in Alphaherpesviruses: Molecular Virology:

ICP22 is the least characterized of the five herpes simplex virus type 1 (HSV-1) immediate-early (IE) proteins. However, accumulating evidence indicates that it carries out a number of interesting regulatory activities inside the infected cell. These include the enhancement of viral gene expression, the modification of RNA polymerase II (RNAP II), and the reorganization of host cell molecular chaperones into nuclear inclusion bodies. Recent studies of engineered HSV-1 mutants indicate that certain of ICP22's activities are genetically separable from each other. Thus, similar to several other of the IE proteins, ICP22 appears to be a multifunctional, multi-domain polypeptide. A recent review summarizes the current state of knowledge concerning ICP22 and its varied regulatory roles during the productive HSV-1 infection.

Further reading: Alphaherpesviruses: Molecular Virology

Intrinsic Resistance to HSV-1 Infection

2010-08-12T08:22:43+01:00

from Roger D. Everett writing in Alphaherpesviruses: Molecular Virology:

In recent years it has become apparent that, in addition to the acquired and innate defences against virus infection, there is also a third aspect to antiviral defences that operates at the intracellular level. This concept is known as intrinsic resistance, intrinsic antiviral defence or intrinsic immunity. Its key features include constitutively expressed cellular proteins that restrict viral gene expression, and viral regulatory proteins that counteract the actions of the cellular inhibitors. A recent review reviews the cellular proteins and pathways that are thought to be involved in intrinsic resistance to HSV-1 infection, and the mechanisms by which these are inactivated by ICP0, an important viral regulatory protein. The phenotype of ICP0 null mutant HSV-1 is described to give a background to the phenomenon, then the principal properties of ICP0 itself are summarised. The effects of ICP0 on components of cellular nuclear structures known as ND10 or PML nuclear bodies are reviewed, then the possible roles of these proteins in intrinsic resistance are discussed. The relationships between ICP0, intrinsic resistance and the regulation of viral chromatin structure are considered, and finally the parallels between ICP0 and related proteins expressed by other alphaherpesviruses are described. Intrinsic resistance and the manner in which viruses overcome it are important aspects of the biology of virus infection, but we have much to learn before we achieve a complete understanding of the viral and cellular proteins that are involved.

Further reading: Alphaherpesviruses: Molecular Virology

HSV-1 ICP27

2010-08-04T08:08:50+01:00

from Rozanne M. Sandri-Goldin writing in Alphaherpesviruses: Molecular Virology:

Herpes simplex virus 1 (HSV-1) protein ICP27 is a multifunctional regulator that is essential for HSV-1 infection. ICP27 performs a number of different functions during infection that include inhibiting cellular pre-mRNA splicing, stimulating viral early and late gene transcription by recruiting cellular RNA polymerase II to viral replication sites, binding and exporting viral RNA to the cytoplasm and stimulating translation of some HSV-1 transcripts by binding translation initiation factors. ICP27 also recruits Hsc70 to nuclear foci (VICE domains) that are enriched in chaperones and components of the proteasome, and which are believed to be involved in nuclear protein quality control. ICP27 interacts with a number of proteins and it binds RNA. Post-translational modifications have been demonstrated to regulate ICP27's interactions with several proteins. NMR analysis of the N-terminus showed that it is highly flexible, which may be necessary for switching between different protein interactions. Further, ICP27 undergoes a head-to-tail intramolecular association that may also regulate its interactions, especially with proteins that require that both the N- and C-termini of ICP27 be intact for interaction. A recent review covers the different activities of ICP27 and what we know about how these activities are regulated.

Further reading: Alphaherpesviruses: Molecular Virology

Immunity to Herpes Simplex Virus

2010-08-04T08:07:06+01:00

from Keith R. Jerome writing in Alphaherpesviruses: Molecular Virology:

HSV presents unique challenges to the human immune system. Most of these result from the ability of the virus to establish latency in neurons of the dorsal root ganglia. The first line of defense against the initial establishment of latent infection is the innate immune response. The innate response relies on a variety of cell types recognizing HSV infection via pattern recognition receptors, including toll-like receptors. After exposure, the adaptive immune response is triggered. However, the adaptive response must deal with reactivation of HSV from the latently infected neuron, which in turn seeds mucosal sites with virus. T cells are especially important in this, and likely control both the extent of reactivation from latently infected neurons as well as the extent of viral replication at mucosal sites. Not surprising, HSV has evolved a wide variety of immune evasion mechanisms to tip this balance in its favor and facilitate transmission to new hosts. The study of HSV and its interaction with the host immune system has provided insights into the function of both, and may ultimately facilitate the development of an effective HSV vaccine.

Further reading: Alphaherpesviruses: Molecular Virology

Strategies Against Herpes Simplex Virus

2010-08-04T08:04:37+01:00

from Timothy E. Dudek and David M. Knipe writing in Alphaherpesviruses: Molecular Virology:

Vaccines have been among the most effective public health approaches for protecting individuals against viral disease, with two of the world's most successful vaccines being against smallpox virus and poliovirus. Herpes simplex virus 1 (HSV-1) is a nearly ubiquitous pathogen, and the worldwide prevalence of herpes simplex virus 2 (HSV-2) continues to increase. These two pathogens cause significant morbidity and mortality among the general population, but in particular in neonates and immunocompromised individuals. Perhaps most significantly, there is a 3-4 fold increased risk of HIV acquisition in HSV-2 infected individuals. To date, attempts at producing a vaccine against HSV have not been successful, but each attempt has brought insights into what may be required for an effective vaccine. Furthermore, intense studies into the immunology of HSV infection and the resources that have been put into vaccine design and development have recently yielded knowledge that will be necessary to achieve the goal of a highly effective vaccine against HSV.

Further reading: Alphaherpesviruses: Molecular Virology

Oral Delivery of Protein Drugs

2010-07-30T09:09:01+01:00

from Müller, 2011

The pathogenesis of common diseases, such as metabolic diseases, is caused by the complex and individual interplay of many susceptibility genes, which necessitates both personalized diagnosis and therapy. Small-molecule drugs which adequately address the multiple tissue-specific target proteins affected probably will not become available in near future. In contrast, therapeutic proteins, such as growth factors and antibodies, specifically replacing or inactivating the corresponding susceptibility gene products, are currently being identified with increasing efficacy. However, the failure to be administered by the oral route and to reach the cytoplasm of the diseased cells typically prevents their therapeutic use. Recent developments suggest that these limitations may be overcome by encapsulation of therapeutic proteins into nanoparticles or their covalent modification with glycolipid (glycosylphosphatidylinositol, GPI) structures. These act as membrane anchors for so-called GPI-anchored proteins and direct certain attached passenger proteins from lipid raft areas of the plasma membrane via cytoplasmic lipid droplets into small vesicles. These leave the donor cells and transfer the GPI-anchored proteins into the cytoplasm of acceptor cells. This pathway may enable the transport of therapeutic proteins across the intestinal barrier into the circulation and eventually across the plasma membrane of the diseased target cells. For therapy, a number of challenges remains to be tackled, in particular, control of release from the GPI anchor which determines the pharmacokinetic and pharmacodynamic profiles. Together these findings nourish the hope that oral path finding to drug targets by encapsulation and covalent modification of therapeutic proteins may enable personalized therapy of common diseases read more ...

Curr. Issues Mol. Biol. (2011) 13: 13-24

Nucleocapsid of Herpes Simplex Virus

2010-07-29T08:23:19+01:00

from James F. Conway and Fred L. Homa writing in Alphaherpesviruses: Molecular Virology:

The herpes simplex virion consists of an external membrane envelope, a proteinaceous layer called the tegument, and an icosahedral capsid containing the double-stranded linear DNA genome. The capsid shell is 125 nm in diameter and consists of 162 capsomers (150 hexons, 11 pentons and a portal) which lie on a T=16 icosahedral lattice. The capsid shell consists of four major structural proteins VP5, VP19C, VP23 and VP26 which are the products of the HSV UL19, UL38, UL18 and UL35 genes. In addition to the four major structural proteins the HSV-1 capsid contains a number of minor capsid proteins. These include the UL6, UL15, UL17, UL25, UL28 and UL33 proteins, all of which (along with the HSV-1 UL32 protein) are required for the processing and packaging of replicated viral DNA into preformed capsid shells. The UL6, UL17, UL25 and UL33 proteins remain associated with DNA containing capsids while UL15 and UL28 do not. A recent review summarizes the present knowledge with respect to how the capsid is assembled, how DNA is packaged and what is known about the role of the seven packaging proteins in this process. In addition, recent advances in our understanding the structure of the four distinct types of capsids that are present in HSV infected cells as determined by three dimensional image reconstructions from cryo¬¨-electron microscopy (cryoEM) are presented and discussed.

Further reading: Alphaherpesviruses: Molecular Virology

Herpes Simplex Virus Entry

2010-07-29T08:21:48+01:00

from Roselyn J. Eisenberg, Ekaterina E. Heldwein, Gary H. Cohen and Claude Krummenacher writing in Alphaherpesviruses: Molecular Virology:

Membrane fusion allows exchange of materials between cellular compartments enclosed by lipid membranes. Similarly, entry of enveloped viruses into cells allows the viral contents to be delivered by fusion of the envelope with a target cell membrane. Fusion requires disruption of both layers of the two membranes. For most enveloped viruses, a single surface glycoprotein undergoes conformational changes that bring the bilayer of the virus in proximity with that of the host cell and fusion ensues. In contrast, herpesvirus entry requires three virion glycoproteins, gB and a gH/gL heterodimer, that function as the core fusion machinery. Some herpesviruses require additional proteins, e.g. alphaherpesviruses (with a few exceptions) initiate fusion by binding of glycoprotein gD to a cell receptor. A conformational change then exposes the normally hidden receptor binding residues of gD. This change and/or the exposed residues trigger gB and gH/gL to effect virus-cell and cell-cell fusion. Because of the multiplicity of proteins involved in HSV entry as opposed to entry of enveloped RNA viruses, it has been difficult to unravel the mechanism of how the four entry glycoproteins function. Some favor formation of a multiprotein fusion complex while others suggest it may be more of a stepwise process. Solution of the structures of all four entry proteins, coupled with existing and new information has solved much of this mystery. We now have a much better idea of the outline of the process, but the challenge for the future will be to fill in important details. It is clear that entry of HSV occurs in an exquisitely regulated stepwise process that begins with binding of gD to a receptor, activation of the regulatory protein gH/gL which in turn up-regulates the fusogenic activity of gB. Thus, in some ways, HSV entry is remarkably similar overall to entry by simpler RNA viruses, such as influenza. A single fusion protein gB carries out fusion. What distinguishes HSV entry is the double regulation of this process.

Further reading: Alphaherpesviruses: Molecular Virology

Translational Control in Herpes Simplex Virus-infected Cells

2010-07-29T08:20:04+01:00

from Ian Mohr writing in Alphaherpesviruses: Molecular Virology:

Like all viruses, alpha-herpesviruses are completely reliant upon the protein synthesis machinery resident in their host cells. In particular, viral mRNAs must effectively compete with cellular mRNAs to engage ribosomes. To ensure high-level production of the polypeptides required for their lytic replication, multiple independent gene products expressed by the model Œ±-herpesvirus HSV-1 effectively seize control of critical host cell translational control pathways. Surprisingly, while host protein synthesis is profoundly suppressed by global changes in mRNA metabolism, the assembly of a multi-subunit, cap-binding translation initiation factor complex required to recruit 40S subunits to mRNA is directly stimulated. This involves both inactivation of a cellular translational repressor by viral functions, and direct interaction between specific viral proteins and select cellular translation initiation factors. In addition to their dependence on cellular components required for mRNA translation, virus-encoded functions must preserve its activity by neutralizing potent host responses capable of incapacitating the translation machinery, one of which senses stress within the endoplasmic reticulum lumen and another of which functions as a host innate defense component by sensing double-stranded RNA, a molecular signature of viral infection. A recent review discusses in detail the many virus-host interactions that are presently known to control translation in cells productively infected with HSV-1 and highlights recent developments in this area.

Further reading: Alphaherpesviruses: Molecular Virology

Herpes Simplex Virus Regulatory Protein ICP4

2010-07-29T08:18:42+01:00

ICP4 is expressed from the HSV genome very early in infection. It is a large structurally complex nuclear phosphoprotein that is essential for viral growth largely due to its requirement for the transcriptional activation of most HSV early and late genes. It also acts a repressor of transcription under certain circumstances. The HSV genome is transcribed by RNA polII, and ICP4 interacts with components of the RNA polII transcription machinery to carry out is functions in transcription. The interactions that are important for its functions can be genetically defined implicating a modular composition of the ICP4 protein. ICP4 also plays a specific role in virus growth in sympathetic neurons implicating a specific function in pathogenesis. A recent review describes what is known about ICP4 from many genetic, biological and biochemical studies, from many laboratories.

Further reading: Alphaherpesviruses: Molecular Virology

Immunity to Varicella Zoster Virus

2010-07-28T17:34:32+01:00

Of three human alphaherpesviruses, only Varicella Zoster Virus (VZV) induces a lifelong immunity that protects against clinical signs of exogenous re-infection and, for most of the population, from any sign of reactivation from the latent state. The importance of VZV specific immunity is exemplified by its absence: severity and morbidity of the primary infection (varicella) and incidence of reactivated disease (zoster) are greatly increased in those with immune compromise, particularly those impaired in the cell mediated immune responses. The protection afforded by VZV specific immunity underlies successful live attenuated vaccines that have greatly impacted the incidence of varicella, and reduce the incidence, severity and complications of zoster. Consequently, the important components of VZV induced immunity and their contribution to the protective state has been well studied and is outlined in a recent review. Less is known of the strategies exploited by VZV to evade the innate and adaptive arms, but their activities are presumed to be critical to extend the life of the infected cell and to enhance viral production and dissemination. Evasion appears to include distinct strategies from those used by Herpes simplex viruses and includes expression of novel immune evasion proteins.

Further reading: Alphaherpesviruses: Molecular Virology

Varicella-Zoster Virus Glycoproteins

2010-07-28T17:32:57+01:00

Varicella zoster virus has a smaller genome than herpes simplex virus and therefore encodes fewer glycoproteins. In a recent review nine VZV glycoproteins are profiled, including gE, gI, gC, gH, gL, gB, gK, gM, and gN. Although all VZV glycoproteins have HSV homologs, functions occasionally have greatly shifted. For example, VZV gE is the predominant VZV glycoprotein and exists as a monomer, dimer and trimer, as well as a gE/gI complex. VZV gE is essential, unlike HSV gE. Even though essential, mutations in gE had been detected in wild type VZV strains that exhibit an accelerated cell-spread phenotype. The VZV gC glycoprotein differs from HSV gC in that both transcription and translation of VZV gC are remarkably delayed in cultured cells; often VZV gC protein is difficult to detect altogether. The VZV gH/gL complex resembles the HSV gH/gL complex is that both are critical for virus induced fusion. Fusion is a prominent feature of VZV infected cells. Neutralization antibody to VZV gH dramatically reduces the spread of virus and limits pathogenesis in the skin. The VZV gB glycoprotein is also involved in virus-induced fusion. Of interest, four VZV glycoproteins (gE, gI, gH and gB) have functional endocytosis motifs in their cytoplasmic tail. Thus, all four are internalized from the cell surface in clathrin coated vesicles. This pathway appears critical for the process of virion envelopment in the assembly compartment. Even though abundant amounts of most glycoproteins are produced in cell culture, assembly of fully enveloped and infectious VZV particles rarely occurs. The particle:plaque forming unit ratio remains an extremely high 40,000:1. Likewise, the aberrant assembly process severely limits any assessment of egress mechanisms.

Further reading: Alphaherpesviruses: Molecular Virology

Varicella Zoster Virus Transcriptional Regulation

2010-07-28T17:31:42+01:00

Varicella-zoster virus (VZV) encodes three immediate-early proteins, IE4, IE62, and IE63; however, only IE62 has TAATGARAT-like sequences in its promoter which are present in the promoters of each of the herpes simplex virus immediate-early proteins. The TAATGARAT-like elements on the IE62 promoter bind to VZV ORF10 protein, Oct, and HCF-1. In addition, histone methyltransferases are recruited to the IE62 promoter to modify chromatin to a transcriptionally active form. VZV IE62, the major VZV transactivator binds to VZV IE4 and IE63, and Med25, part of the mediator complex which upregulates gene expression. VZV IE62, IE4, and IE63 are present in the viral tegument where they may help to regulate transcription early in infection. IE63 binds to several cellular proteins including ASF1 and RNA polymerase II. Two hypotheses have been proposed for regulation of VZV gene expression during latency. First, relocalization of HCF-1 from the cytoplasm to the nucleus of sensory ganglia in response to stimuli associated with reactivation may help to augment transcription of IE62 to reactivate VZV from latency. Second, promoters of latent genes are maintained in a euchromatic state allowing their transcription, while promoters of genes not associated with latency are in a heterochromatic state resulting in repression of transcription.

Further reading: Alphaherpesviruses: Molecular Virology

Iron Uptake Book Available

2010-07-22T11:54:23+01:00

The new book on Iron Uptake and Homeostasis in Microorganisms edited by Pierre Cornelis and Simon C. Andrews has been published read more ...

Iron Uptake and Homeostasis in Microorganisms

Edited by: Pierre Cornelis and Simon C. Andrews
ISBN: 978-1-904455-65-3
Publisher: Caister Academic Press
Publication Date: June 2010
Cover: hardback

Bifidobacteria Book Available

2010-07-22T11:52:35+01:00

The new book on Bifidobacteria: Genomics and Molecular Aspects edited by Baltasar Mayo and Douwe van Sinderen has been published read more ...

Bifidobacteria: Genomics and Molecular Aspects

Edited by: Baltasar Mayo and Douwe van Sinderen
ISBN: 978-1-904455-68-4
Publisher: Caister Academic Press
Publication Date: August 2010
Cover: hardback

Biopolymers Book Review

2010-07-21T15:50:20+01:00

I am pleased to provide the following excerpt from a book review of Microbial Production of Biopolymers and Polymer Precursors: Applications and Perspectives:

"The authors of this comprehensive review are internationally accepted specialists in the field of using microorganisms as a cell factory for biopolymers or special precursors of these polymers ... The editor and the authors have produced an excellent up-to date compendium which is extremely useful for all students of biotechnology, engineering and scientists in the biotechnological and microbiological branches and is recommended for all biotechnological and microbial laboratories and enterprises in this field. It should be available in libraries at universities, research institutes and biotechnological companies and is further strongly recommended to all those who are interested in life sciences." from Uta Breuer (Halle, Germany) writing in Clean (2009) 37(6): 414 read more ...

Microbial Production of Biopolymers and Polymer Precursors: Applications and Perspectives

Edited by: Bernd H. A. Rehm
ISBN: 978-1-904455-36-3
Publisher: Caister Academic Press
Publication Date: January 2009
Cover: hardback

"an excellent up-to date compendium ... strongly recommended" (Clean)

ABC Transporters Book Review

2010-07-21T11:33:30+01:00

I am pleased to provide the following excerpt from a book review of ABC Transporters in Microorganisms:

"a good text book for basic science researchers in the area of multiple drugs resistant (MDR) proteins or microbiology. This book comprehensively discusses various types of ABC transporters and their implications for microorganisms such as bacterial, yeast, fungi, and parasites ... extensive information regarding biological structure, molecular machineries ... and cellular functions ... this book offers valuable resources and may provide insights into the unknown functions and physiological roe of ABC transporters in humans" from Dr YS Loh (University of Sydney, Australia) writing in Aus. J. Med. Sci. (2010) 31(2): 73 read more ...

ABC Transporters in Microorganisms

Edited by: Alicia Ponte-Sucre
ISBN: 978-1-904455-49-3
Publisher: Caister Academic Press
Publication Date: August 2009
Cover: hardback

"this book offers valuable resources" (Aus. J. Med. Sci.)

Metagenomics Book Review

2010-07-21T09:08:07+01:00

I am pleased to provide the following excerpt from a book review of Metagenomics: Theory, Methods and Applications:

"The book contains expert reviews on the approach, tools and prospects of metagenomics, on detailed methodologies, on a number of translational applications, and one chapter on conceptualization of the approach and its standing in the natural sciences ... All chapters have exciting concluding remarks, outlining challenges and future perspectives - a hallmark of a young and rapidly rising research area. Most references are from the most recent 10 years, reaching far into 2009, also reflecting the recent advent of this research branch. The book identifies a milestone in modern microbiology with vast impact on other disciplines, and is highly recommended to students and practitioners of molecular biology, biochemistry, all branches of microbiology, bioinformatics, and, last but not least, medicine." from Ulrich Desselberger (Cambridge) writing in Microbiology Today (2010) read more ...

Metagenomics: Theory, Methods and Applications

Edited by: Diana Marco
ISBN: 978-1-904455-54-7
Publisher: Caister Academic Press
Publication Date: January 2010
Cover: hardback

"highly recommended" (Microbiol. Today)

Borrelia Book Review

2010-07-21T08:50:38+01:00

I am pleased to provide the following excerpt from a book review of Borrelia: Molecular Biology, Host Interaction and Pathogenesis:

"an encyclopaedic account of this riveting story of modern biology, contributed by experts, many of whose career in science has spanned the whole era from discovery through to deep understanding of the pathogen. It is a fabulous resource for those in the field and full of surprises and insights for the outsider." from Charles Penn (University of Birmingham) writing in Microbiology Today (2010) read more ...

Borrelia: Molecular Biology, Host Interaction and Pathogenesis

Edited by: D. Scott Samuels and Justin D. Radolf
ISBN: 978-1-904455-58-5
Publisher: Caister Academic Press
Publication Date: March 2010
Cover: hardback

"a fabulous resource" (Microbiol. Today)

Retrovirus Book Review

2010-07-21T08:38:19+01:00

I am pleased to provide the following excerpt from a book review of Retroviruses: Molecular Biology, Genomics and Pathogenesis:

"a succinct, state-of-the-art summary of the biology not only of retroviruses but also other retroelements ... comprehensive, convenient and satisfying reference work" from Charles Bangham (Imperial College London, UK) writing in Microbiology Today (2010) read more ...

Retroviruses: Molecular Biology, Genomics and Pathogenesis

Edited by: Reinhard Kurth and Norbert Bannert
ISBN: 978-1-904455-55-4
Publisher: Caister Academic Press
Publication Date: January 2010
Cover: hardback

"a succinct, state-of-the-art summary" (Microbiol. Today)

Another Influenza Book Review

2010-07-20T15:28:02+01:00

I am pleased to provide the following excerpt from a book review of Influenza: Molecular Virology:

"I particularly enjoyed a very thorough account of the influenza A haemagglutinin ... it's a nicely put together book that summarizes recent developments on the structural side of influenza replication. Appropriate audiences for the book would be final-year virology students and influenza researchers." from Paul Digard (University of Cambridge, UK) writing in Microbiol. Today (2010) read more ...

Influenza: Molecular Virology

Edited by: Qinghua Wang and Yizhi Jane Tao
ISBN: 978-1-904455-57-8
Publisher: Caister Academic Press
Publication Date: February 2010
Cover: hardback

"a nicely put together book" (Microbiol. Today)

Influenza Book Review

2010-07-20T14:17:00+01:00

I am pleased to provide the following excerpt from a book review of Influenza: Molecular Virology:

"a series of excellent and high-powered articles on the molecular virology of influenza ... provides an up-to-date review of the advancements in molecular influenza virology, with additional discussions regarding the use of molecular technology in diagnostic platforms, and statistical modeling to quantify antigenic differences between influenza viruses ... of interest to a range of readers including post-graduate and basic science researchers, virologists and those involved with drug design and development." from Iain Stephenson (Leicester Royal Infirmary, Leicester, UK) writing in Expert Rev. Vaccines (2010) 9: 719-720. read more ...

Influenza: Molecular Virology

Edited by: Qinghua Wang and Yizhi Jane Tao
ISBN: 978-1-904455-57-8
Publisher: Caister Academic Press
Publication Date: February 2010
Cover: hardback

"a series of excellent and high-powered articles" (Expert Rev. Vaccines)

EBV Book Review

2010-07-20T13:54:11+01:00

I am pleased to provide the following excerpt from a book review of Epstein-Barr Virus: Latency and Transformation:

"the latest research and information on the mechanisms used by latent EBV to transform host cells ... a comprehensive review of the vast amount of information that is currently available ... a good book for scientists ... packed with valuable information" from Rebecca T. Horvat (University of Kansas Medical Center, USA) writing in Doodys read more ...

Epstein-Barr Virus: Latency and Transformation

Edited by: Erle S. Robertson
ISBN: 978-1-904455-62-2 (hardback); 978-1-904455-64-6 (paperback).
Publisher: Caister Academic Press
Publication Date: April 2010
Cover: hardback

"packed with valuable information" (Doodys)

Nanotechnology in Water Treatment Applications

2010-07-16T16:26:50+01:00

The new book on Nanotechnology in Water Treatment Applications edited by T. Eugene Cloete, Michele de Kwaadsteniet, Marelize Botes and J. Manuel López-Romero has been published read more ...

Nanotechnology in Water Treatment Applications

Edited by: T. Eugene Cloete, Michele de Kwaadsteniet, Marelize Botes and J. Manuel López-Romero
ISBN: 978-1-904455-66-0
Publisher: Caister Academic Press
Publication Date: June 2010
Cover: hardback

Molecular Phylogeny of Microorganisms

2010-07-16T16:24:13+01:00

The new book on Molecular Phylogeny of Microorganisms edited by Aharon Oren and R. Thane Papke has been published read more ...

Molecular Phylogeny of Microorganisms

Edited by: Aharon Oren and R. Thane Papke
ISBN: 978-1-904455-67-7
Publisher: Caister Academic Press
Publication Date: July 2010
Cover: hardback

Respiratory Synctial Virus Symposium

2010-07-01T11:01:31+01:00

December 2 - 5, 2010 Respiratory Synctial Virus Symposium

Rotterdam, Netherlands Further information
The symposium is the flagship event for leading investigators engaged in RSV research around the world. The objectives of the symposium are to provide a forum to help develop and deliver advancements in RSV research and to provide excellent peer-to-peer networking. The symposium will cover the following topics: Pathogenesis, Structure, Entry, Replication and Cell Biology, Clinical and Diagnostic Aspects, Immunology: Innate and Adaptive, Vaccine Development and Therapeutics: Antiviral and Other Strategies
Suggested reading: Virology Books

Influenza Conference

2010-07-01T10:59:31+01:00

September 11 - 14, 2010 Fourth ESWI International Conference

Malta Further information
Fourth ESWI International Conference devoted to influenza to be held in Malta.The meeting will provide comprehensive scientific coverage of all disciplines involved in influenza prevention, control and treatment. Top-level scientific sessions with specific attention for new developments are the core of the conference. Additionally, the conference has a clearly delineated programme for public health officials and opinion leaders in health care work. These sessions also cover a broad field of interest and will certainly include an evaluation of the H1N1 influenza pandemic.
Suggested reading: Influenza: Molecular Virology

Aquatic Microbiology Conference

2010-07-01T10:57:17+01:00

September 2 - 4, 2010 Aquatic Microbiology (Status, Challenges, and Opportunities)

Tamilnadu, India Further information
Aquatic microbiology is the science that deals with microscopic living organisms in fresh and salt water systems. Though aquatic microbiology encompasses all microorganisms, including microscopic plants and animals, it refers more commonly to the study of bacteria, actinobacteria, fungi and viruses and their relationships to other organisms in the aquatic environment. Aquatic microbial research embraces a variety of disciplines, ranging from molecular biology and physiology to population dynamics and ecosystem ecology. Aquatic microbes especially in the marine biotopes play a significant role in oceanic processes such as synthesising food, decomposing organic matter, recycling nutrients, and effecting climatic conditions. Although microbes constitute over 90% of oceanic biomass, their biodiversity remains largely unexplored. Microbial diversity and its functions will be significantly affected by critical phenomena such as ocean warming and EI Nino oscillation. Microbial biotechnological approaches and molecular techniques continue to provide us with information on microbes potential for various industrial applications, bio-geographical diversity and phylogeny. There is immense scope for bio-prospecting of aquatic microbes for a wide range of applications. Thus, aquatic microbiology remains instrumental for innovations and future discoveries.
Suggested reading: Nanotechnology in Water Treatment Applications

Plant Viral Vectors

2010-06-30T08:12:45+01:00

Plant Viral Vectors for Protein Expression
from Yuri Y. Gleba and Anatoli Giritch writing in Recent Advances in Plant Virology

Plant-virus-driven transient expression of heterologous proteins is the basis of several mature manufacturing processes that are currently being used for the production of multiple proteins including vaccine antigens and antibodies. Viral vectors have also become useful tools for research. In recent years, advances have been made both in the development of first-generation vectors (those that employ the 'full virus' strategy) as well as second-generation vectors designed using the 'deconstructed virus' approach. This second strategy relies on Agrobacterium as a vector to deliver DNA copies of one or more viral RNA replicons. Among the most often used viral backbones are those of Tobacco mosaic virus, Potato virus X, and Cowpea mosaic virus. Prototypes of industrial processes that provide for high-yield, rapid scale-up, and fast manufacturing have been recently developed using viral vectors, with several manufacturing facilities compliant with good manufacturing practices (GMP) in place, and a number of pharmaceutical proteins currently in pre-clinical and clinical trials.

Further reading: Recent Advances in Plant Virology | Virology Publications

Viruses in Nanotechnology

2010-06-30T08:09:10+01:00

Virus Particles and the Uses of Such Particles in Bio- and Nanotechnology
from George P. Lomonossoff writing in Recent Advances in Plant Virology

The capsids of most plant viruses are simple and robust structures consisting of multiple copies of one or a few types of protein subunit arranged with either icosahedral or helical symmetry. The capsids can be produced in large quantities either by the infection of plants or by the expression of the subunit(s) in a variety of heterologous systems. In view of their relative simplicity and ease of production, plant virus particles or virus-like particles (VLPs) have attracted much interest over the past 20 years for applications in both bio- and nanotechnology. As result, plant virus particles have been subjected to both genetic and chemical modification, have been used to encapsulate foreign material and have, themselves, been incorporated into supramolecular structures.

Further reading: Recent Advances in Plant Virology | Virology Publications | Nanotechnology in Water Treatment Applications | Virology Publications

Viral Sequences in Plant Genomes

2010-06-30T08:06:32+01:00

Endogenous Viral Sequences in Plant Genomes
from Pierre-Yves Teycheney and Andrew D.W. Geering writing in Recent Advances in Plant Virology

Endogenous viral sequences from members of two virus families, the Caulimoviridae and Geminiviridae, have been discovered in several monocotyledonous and dicotyledonous plant species. For the most part, these sequences are replication-defective but those capable of causing infection have been discovered in tobacco (Nicotiana edwardsonii), petunia (Petunia hybrida) and banana and plantain (Musa spp.). Activation of endogenous caulimovirid sequences is one of the major impediments to international banana and plantain breeding efforts. Research on endogenous viral sequences in plants is still in its infancy, with little known about the contributions of these sequences to host and virus evolution, nor even a classification system adopted. On a practical note, problems still exist with differentially detecting viral genomic DNA in a host genetic background containing endogenous viral sequences, and a solution to the problem of activation of endogenous viral sequences in banana is still far away.

Further reading: Recent Advances in Plant Virology | Virology Publications

Viral Species Diversity of Plants

2010-06-30T08:03:45+01:00

Genomic Approaches to Discovery of Viral Species Diversity of Non-cultivated Plants
from Ulrich Melcher and Veenita Grover writing in Recent Advances in Plant Virology

Outbreaks of newly emerging and re-emerging animal and plant viruses pose a constant threat to public health and food security and emphasize the need to develop efficient methods for viral detection and identification. Ongoing studies for discovery of viral species in non-cultivated plants utilize genomic approaches for systematic unbiased searches for viruses related to known viruses. Genomic approaches use various combinations of methods for sampling the environment, enriching samples for content of viral genomes, amplifying nucleic acids, and detecting virus-related sequences among the amplified nucleic acids. These methods include particularly array hybridization to macroarrays and microarrays, and various megasequencing approaches. In all cases, relatives of known viruses are discovered. However, the identification of a novel plant virus completely unrelated to known ones remains a challenge. Despite a growing list of viruses infecting wild plants, virus infections in wild plant communities are often underestimated relative to cultivated systems, since viruses in wild plants are generally considered not to harm the host. Viruses may not be explicitly damaging wild plants, but their biodiversity and abundance suggest an important role of these viruses in ecosystems. These roles should not be under-rated just because they are under-researched.

Further reading: Recent Advances in Plant Virology | Virology Publications

Begomovirus

2010-06-30T08:01:31+01:00

Emergence of Begomovirus Diseases
from Enrique Moriones, Jesus Navas-Castillo and Juan-Antonio Díaz-Pendón writing in Recent Advances in Plant Virology

Begomoviruses (genus Begomovirus, family Geminiviridae) rank among the top of the most important plant viruses causing disease of severe consequences in economically and socially relevant crops. From the early 1990s, a rapid emergence and geographic expansion of begomoviruses has occurred worldwide. As a result, these viruses have become the most destructive group of plant viruses in tropical and subtropical regions of the world. Their emergence is associated with the emergence of populations of the insect vector, the whitefly Bemisia tabaci, probably due to increased plant trading between distantly separated geographical regions and changes in agricultural practices. Human activity seems to have been a major factor promoting emergence of begomoviruses. Other factors also drive emergence.

Further reading: Recent Advances in Plant Virology | Virology Publications

Emergence of Plant RNA Viruses

2010-06-29T14:27:40+01:00

Evolutionary Constraints on Emergence of Plant RNA Viruses
from Santiago F. Elena writing in Recent Advances in Plant Virology

Over the recent years, agricultural activity in many regions has been compromised by a succession of devastating epidemics caused by new viruses that switched host species, or by new variants of classic viruses that acquired new virulence factors or changed their epidemiological patterns. Although viral emergence has been classically associated with ecological change or with agronomical practices that brought in contact reservoirs and crop species, it has become obvious that the picture is much more complex, and results from an evolutionary process in which the main players are the changes in ecological factors, the tremendous genetic plasticity of viruses, the several host factors required for virus replication, and a strong stochastic component. A recent review puts the emergence of RNA viruses into the framework of evolutionary genetics and reviews the basic notions necessary to understand emergence, stressing that viral emergence begins with a stochastic process that involves the transmission of a pre-existing viral strain with the right genetic background into a new host species, followed by adaptation to the new host during the early stages of infection.

Further reading: Recent Advances in Plant Virology | Virology Publications

Plant Infection by Viruses

2010-06-29T14:25:05+01:00

Population Dynamics and Genetics of Plant Infection by Viruses
from Fernando García-Arenal and Aurora Fraile writing in Recent Advances in Plant Virology

During the last thirty years, progress in understanding the mechanistic aspects of virus-plant interactions has been remarkable, notably in aspects such as genome replication, movement within the infected host or pathogenesis and resistance. Progress in understanding the population dynamics and genetics of plant infection by viruses has not been as great. However, understanding the kinetics of plant colonisation and the genetic structure of the within-host virus population is necessary for addressing many issues of plant-virus interaction and of virus evolution. The quantitative aspects of plant infection and colonisation by viruses were mostly addressed during the early period of plant virology, when many detailed studies were published that often incorporated mathematical modelling. These issues have not been thoroughly re-examined using molecular techniques. Recent work has focussed on the description of the genetic structure of the virus population at the organ and the plant level. Data suggest that in spite of huge fecundity, the effective numbers of the within-host virus population may be small due to severe population bottlenecks at each stage of plant infection and colonisation, which results in a spatially structured population.

Further reading: Recent Advances in Plant Virology | Virology Publications

Control Measures Against Viruses

2010-06-29T14:23:22+01:00

Integrated Control Measures Against Viruses and Their Vectors
from Alberto Fereres and Aranzazu Moreno writing in Recent Advances in Plant Virology

Viruses and their vectors produce severe damage to crops worldwide. Of importance are the strategies and tactics used to manage vectors of plant viruses, with special attention to insects, by far the most important type of vector. The philosophy and principles of Integrated Pest Management (IPM) developed long ago can still provide an effective and sustainable way to manage insect vectors of virus diseases of plants. Preventive strategies such as the development of models that forecast virus disease outbreaks together with host plant resistance, cultural and physical tactics are the most effective ways to control nonpersistently-transmitted viruses. A reduction in vector numbers using conventional systemic insecticides or innundative biological control agents can also provide effective control of persistently-transmitted viruses. Recent advances on understanding of the mode of transmission of plant viruses are also a very promising way to develop molecules to block putative virus binding sites within the vector and to avoid virus retention and transmission. Also, the characterization of aphid's salivary components that is underway may facilitate the development of new tools to interfere with the process of transmission of plant viruses.

Further reading: Recent Advances in Plant Virology | Virology Publications

Resistance to Viruses in Plants

2010-06-29T14:20:02+01:00

Sustainable Management of Plant Resistance to Viruses
from Benoît Moury, Alberto Fereres, Fernando García-Arenal and Hervé Lecoq writing in Recent Advances in Plant Virology

Although viruses are among the parasites which induce the most severe damages on cultivated plants, few control methods have been developed against them. Notably, no curative methods can be applied against virus diseases in crops. In view of this major economic problem, the development of resistant cultivars has become a critical factor of competitiveness for breeders. However, plant - virus interactions are highly dynamic and the selective pressure exerted by plant resistance frequently favours the emergence of adapted virus populations. Given the scarcity of resistance genes, there is consequently an urgent need to increase the sustainability of these genetic resources. A recent publication reviews the biological mechanisms which allow the emergence of virus populations adapted to plant resistances and how we can use this knowledge to explain the relative durability of different resistance genes, to built predictors of resistance durability and to combine the use of resistances with other control methods to increase their sustainability.

Further reading: Recent Advances in Plant Virology | Virology Publications

Virus Resistance in Plants

2010-06-29T14:17:44+01:00

Advanced Breeding for Virus Resistance in Plants
from Alain Palloix and Frank Ordon writing in Recent Advances in Plant Virology

Breeding for virus resistance was successful in the past years using conventional breeding methods since many virus resistant cultivars have been delivered for a wide range of crops. Genome mapping provided molecular markers for many resistance loci (i.e., major genes or Quantitative Trait Loci) that were introgressed into cultivars e.g., through backcross breeding schemes. Molecular mapping also delivered much information on the genomic architecture of polygenic and quantitative resistances. However, marker assisted selection for such complex traits is difficult so that the combination of quantitative resistance factors from multiallelic origins commonly relies on sophisticated phenotyping procedures. The cloning of resistance genes and the rapid development of high throughput molecular technologies increased the access to functional markers and multiallelic markers, promoting the applicability of marker assisted selection for complex traits at the whole genome scale in the near future. In parallel, the advances in the identification of molecular determinants of plant/virus interactions and in genetics and evolution of virus populations provide new selection criteria for breeders to choose the most durable resistance genes and gene combinations, so that breeding for durable virus resistance becomes an accessible quest.

Further reading: Recent Advances in Plant Virology | Virology Publications

Plant Resistance to Viruses

2010-06-29T14:14:55+01:00

Plant Resistance to Viruses Mediated by Translation Initiation Factors
from Olivier Le Gall, Miguel A. Aranda and Carole Caranta writing in Recent Advances in Plant Virology

Host resistance to viruses can show dominant or recessive inheritance. Remarkably, recessive resistance genes are much more common for viruses than for other plant pathogens. Recessive resistances to viruses are especially well documented within the dicotyledons, and have been described for various viruses that belong to very different viral genera, although clearly they predominate among viruses belonging to the genus Potyvirus. The elucidation of the molecular nature of this particular class of resistance genes is recent, but has so far only revealed a group of proteins linked to the translation machinery, chiefly the eukaryotic translation initiation factors (eIF) 4E and 4G. There are specific features and mechanisms of eIF4E- and 4G-mediated resistances to potyviruses and viruses belonging to other genera, such as carmoviruses.

Further reading: Recent Advances in Plant Virology | Virology Publications

NB-LRR Immune Receptors in Plant Virus Defense

2010-06-29T08:37:29+01:00

NB-LRR Immune Receptors in Plant Virus Defense
from Patrick Cournoyer and Savithramma P. Dinesh-Kumar writing in Recent Advances in Plant Virology

Resistance genes protect plants from infection by viruses and many other classes of pathogens. The dominant, anti-viral R genes that have been cloned thus far encode NB-LRR immune receptors that detect a single viral protein and trigger defense. Many different types of viral proteins are known to elicit defense by corresponding NB-LRRs. Defense often results in a type of localized programmed cell death at the site of attempted pathogen infection known as the hypersensitive response (HR-PCD), but some NB-LRRs confer resistance to viruses without HR-PCD. The activation of NB-LRRs triggers manifold signaling events including reactive oxygen species (ROS) production, nitric oxide (NO) production, calcium (Ca²⁺) influx, activation of mitogen activated protein kinases (MAPKs), and production of the plant hormones salicylic acid (SA), jasmonic acid (JA), and ethylene. After a successful NB-LRR-mediated defense event, the plant exhibits heightened resistance to future pathogen challenge in a state called systemic acquired resistance.

Further reading: Recent Advances in Plant Virology | Virology Publications

Viral Suppressors of RNA Silencing

2010-06-29T08:35:04+01:00

Mechanism of Action of Viral Suppressors of RNA Silencing
from József Burgyán writing in Recent Advances in Plant Virology

RNA silencing is an evolutionarily conserved sequence-specific gene-inactivation system that also functions as an antiviral mechanism in higher plants and insects. To overcome this defence system, viruses encode suppressors of RNA silencing, which can counteract the host silencing-based antiviral process. More than 50 individual viral suppressors have been identified from almost all plant virus genera, underlining their crucial role in successful virus infection. Viral suppressors are considered to be of recent evolution, and they are surprisingly diverse within and across kingdoms, exhibiting no obvious sequence similarity. Virus-encoded silencing suppressors can target several key components in the silencing machinery, such as silencing-related RNA structures and essential effector proteins and complexes. There has been much recent progress in our understanding of the mechanism and function of viral suppressors of antiviral RNA silencing in plants.

Further reading: Recent Advances in Plant Virology | Virology Publications | RNA and the Regulation of Gene Expression

miRNAs in Mammalian Antiviral Immune Responses

2010-06-29T08:32:28+01:00

Virus-encoded Suppressors of RNA Silencing and the Role of Cellular miRNAs in Mammalian Antiviral Immune Responses
from Joost Haasnoot and Ben Berkhout writing in RNA Interference and Viruses
Small RNA-directed silencing mechanisms play important roles in the regulation of eukaryotic gene expression. In plants, insects, nematodes and fungi RNA silencing mechanisms are also involved in innate antiviral defence responses. To counter antiviral RNA silencing, viruses from plants, insects and fungi encode RNA silencing suppressors (RSSs). Recent studies suggest that RNA silencing in mammals, or RNA interference (RNAi), is also involved in antiviral responses. In particular, there is increasing evidence that cellular regulatory microRNAs (miRNAs) have a function in restricting virus replication in mammalian cells. Similar to plant and insect viruses, several mammalian viruses encode RSS factors that inhibit the RNAi mechanism. Several of these suppressors are multifunctional proteins that were previously shown to block innate antiviral immune responses involving the interferon (IFN) pathway.

Further reading: Recent Advances in Plant Virology | RNA Interference and Viruses | RNA and the Regulation of Gene Expression

RNA Silencing in Plants and Viral Suppressors

2010-06-29T08:29:06+01:00

RNA Silencing in Plants and the Role of Viral Suppressors
from Ana Giner, Juan Jose Lopez-Moya and Lorant Lakatos writing in RNA Interference and Viruses
The term RNA silencing refers to several pathways present in eukaryotic organisms that lead to the sequence specific elimination or functional blocking of RNAs with homology to double stranded RNAs (dsRNAs) that have previously triggered the mechanism. Besides playing important roles in developmental control, RNA silencing forms part of the defence against viruses in plants, acting as a potent antiviral mechanism. To escape from the RNA silencing-based defence, most plant viruses make use of different strategies, the most common relying in the action of viral proteins with the capacity to suppress RNA silencing. The characterization of these viral suppressors is providing useful insights to understand how RNA silencing works, revealing components and steps in the silencing pathways.

Further reading: Recent Advances in Plant Virology | RNA Interference and Viruses | RNA and the Regulation of Gene Expression

RNA Silencing and the Interplay Between Plants and Viruses

2010-06-29T08:23:03+01:00

RNA Silencing and the Interplay Between Plants and Viruses
from Lourdes Fernández-Calvino, Livia Donaire and César Llave writing in Recent Advances in Plant Virology

In eukaryotes, RNA silencing controls gene expression to regulate development, genome stability and stress-induced responses. In plants, this process is also recognized as a major immune system targeted against plant viruses. Plant viruses stimulate RNA silencing responses though formation of viral RNA with double-stranded features that are subsequently processed into functional small RNAs (sRNAs). Recent studies highlight the complexity of the viral sRNA populations and their potential to associate with multiple silencing effector complexes. This fact has profound implications in the cross-talk interactions between plants and viruses since both virus genomes and host genes are putative targets of viral sRNAs. The concept of RNA silencing is an elegant natural antiviral mechanism in plants. Viral sRNA-mediated regulation of gene expression is important in the frame of compatible interactions between plants and viruses.

Further reading: Recent Advances in Plant Virology | Virology Publications | RNA and the Regulation of Gene Expression

Vector-mediated Transmission

2010-06-29T08:20:49+01:00

Functions of Virus and Host Factors During Vector-mediated Transmission
from Stéphane Blanc and Martin Drucker writing in Recent Advances in Plant Virology

Most plant viruses are transmitted by living vectors that transport viruses to a new host plant. One discriminates between circulative transmission, where viruses must pass through the vector interior and are usually inoculated with the saliva on a healthy plant, and non-circulative transmission, where viruses do not need to pass through the vector interior but are directly inoculated from the mouth parts into a new host. Especially transmission of non-circulative viruses has been regarded as a simple process where a vector more or less accidentally transports the virus. However, it becomes more and more evident that this scenario is unlikely, because transmission constitutes a dramatic bottleneck of the virus life cycle, where only very few viral genomes pass to a new host, and where a given virus must do everything to ensure successful transmission. Viruses, also in non-circulative transmission, deliberately manipulate their hosts and vectors in often very unexpected ways to optimise their transmission.

Further reading: Recent Advances in Plant Virology | Virology Publications

Movement of Viruses Via the Plant Phloem

2010-06-29T08:17:31+01:00

Systemic Movement of Viruses Via the Plant Phloem
from Vicente Pallás, Ainhoa Genovés, M. Amelia Sánchez-Pina and José Antonio Navarro writing in Recent Advances in Plant Virology

The incorporation of non invasive techniques has allowed remarkable progress in our understanding of the vascular transport of plant viruses. Indeed, approximately seventy-five percent of reports about this topic have been published after the first use of the jellyfish green fluorescent protein (GFP) in plant virology. In the last two decades, a very detailed picture of the viral determinants involved in phloem transport of plant viruses has been obtained. However, we realize that most virus-host interactions are pathosystem-specific and, consequently, the identification of common host factors involved in phloem transport of plant viruses is the exception rather than the rule. In addition, we are still far from obtaining a clear picture of how environmental factors influence the vascular invasion of plants by these pathogens. A recent publication reviews the progress made in understanding the viral determinants involved in vascular transport of viruses and the pathways followed by viruses during systemic movement, and focuses on host and environmental conditions that influence the final distribution of viruses in the plant.

Further reading: Recent Advances in Plant Virology | Virology Publications

Plasmodesmata and Virus Movement

2010-06-28T16:15:04+01:00

Plasmodesmata as Active Conduits for Virus Cell-to-Cell Movement
from Lourdes Fernandez-Calvino, Christine Faulkner and Andy Maule writing in Recent Advances in Plant Virology

It has been known for many decades that viruses need to exploit plasmodesmata as channels of cytoplasmic connectivity through plant cell walls. However, we do not yet understand the molecular mechanisms involved in moving a single infectious entity from cell to cell, although it is clear that virus-encoded movement proteins play a central role. Major progress has been made in identifying movement proteins, their associations with subcellular structures/organelles, and their biochemical properties with respect to nucleic acid-binding and physical associations with host and other viral proteins. These studies reveal a specificity in functional evolution where viruses share some similarities in their movement strategies with near and far phylogenetic groups but show few examples of processes that might apply to all or many individual viruses. Plasmodesmata also provide channels for cellular communication essential for plant growth, development and defense. As such, there is increasing attention aimed at resolving their constituent components necessary for structure and function. With the limited success of genetic screens, proteomic analysis of biochemically-enriched plasmodesmal fractions has also been pursued. Through the identification of plasmodesmal proteins we will have the opportunity to understand how movement proteins bring about the massive changes in the physical behaviour of plasmodesmata that result in the translocation of the macromolecular complexes responsible for virus infectivity.

Further reading: Recent Advances in Plant Virology | Virology Publications

Plant RNA Viruses

2010-06-28T16:13:28+01:00

Replication of Plant RNA Viruses
from Peter D. Nagy and Judit Pogany writing in Recent Advances in Plant Virology

Among plant viruses, the positive-stranded RNA [(+)RNA] viruses are the largest group, and the most widespread. The central step in the infection cycle of (+)RNA viruses is RNA replication, which is carried out by virus-specific replicase complexes consisting of viral RNA-dependent RNA polymerase, one or more auxiliary viral replication proteins, and a number of co-opted host factors. Viral replicase complexes assemble in specialized membranous compartments in infected cells. Sequestering the replicase complexes is not only helpful for rapid production of a large number of viral (+)RNA progeny, but it also facilitates avoiding recognition by the host¹s anti-viral surveillance system, and it provides protection from degradation of the viral RNA. Successful viral replication is followed by cell-to-cell and long-distance movement throughout the plant, as well as encapsidation of the (+)RNA progeny to facilitate transmission to new plants. A recent review provides an overview of our current understanding of the molecular mechanisms in plant (+)RNA virus replication. Recent significant progress in this research area is based on development of powerful in vivo and in vitro methods, including replicase assays, reverse genetic approaches, intracellular localization studies, genome-wide screens for co-opted host factors and the use of plant or yeast model hosts.

Further reading: Recent Advances in Plant Virology | Virology Publications | RNA and the Regulation of Gene Expression

Translation of Viral RNAs

2010-06-28T16:11:06+01:00

Roles of Cis-acting Elements in Translation of Viral RNAs
from W. Allen Miller, Jelena Kraft, Zhaohui Wang and Qiuling Fan writing in Recent Advances in Plant Virology

Cis-acting signals regulate translation of viral RNAs to produce viral proteins at the appropriate levels and timing to maximize virus replication. A recent review describes the cis-acting sequences that achieve this translational control via processes such as cap-dependent translation, leaky scanning to initiate translation at more than one start codon, ribosomal shunting, cap-independent translation initiation controlled from the 5' and/or 3' untranslated region, poly(A) tail-independent translation initiation, stop codon readthrough, and ribosomal frameshifting. Secondary structures and, in some cases, tertiary structures of the RNA sequences control these events and translation events facilitated by the cis-acting signals mesh with the overall replication strategies of the diverse viruses that employ these mechanisms.

Further reading: Recent Advances in Plant Virology | Virology Publications

SARS Vaccine

2010-06-24T14:57:55+01:00

Vaccines Against Newly Emerging Viral Diseases: The Example of SARS
from Bart L. Haagmans writing in Vaccine Design: Innovative Approaches and Novel Strategies

Several newly emerging viral diseases in humans have been reported recently. The ability to identify and characterize the relevant pathogen and develop safe and effective vaccines against these newly emerging pathogens in a timely manner is utmost importance. In this respect, the global response to the SARS epidemic provided valuable experience which can be utilized to respond quickly to future emerging viral infections. In only a few weeks time the nucleotide sequence of this virus was available and through computational analysis of gene sequences diagnostic tests and vaccine candidates were identified and subsequently developed. Eight years after the first SARS outbreak several candidate SARS-CoV vaccines are at various stages of pre-clinical and clinical development. The "classical" inactivated whole virus vaccine as well as a DNA vaccine expressing the spike gene ultimately reached the phase 1 clinical trial testing. These vaccines induce neutralizing antibodies to SARS-CoV and protect against SARS-CoV challenge. However, these vaccines still need to be further tested against viruses closely related to SARS-CoV that potentially may emerge and for the absence of significant side effects. The lessons learned from this outbreak combined with more recently developed techniques may aid the development of effective vaccines against future emerging viral diseases.

Further reading: Vaccine Design: Innovative Approaches and Novel Strategies | Coronaviruses: Molecular and Cellular Biology

Veterinary Vaccines

2010-06-24T14:55:54+01:00

Veterinary Vaccines with a Focus on Bovine Mastitis
from John R. Middleton writing in Vaccine Design: Innovative Approaches and Novel Strategies

While novel approaches to vaccination against diseases of veterinary importance are being explored, currently marketed products, in general, employ old technology with the majority of products still being killed, modified live, or toxoid preparations. Due to the breadth of diseases encountered in veterinary medicine and the large number of vaccines marketed and under development, a recent review focuses on vaccines aimed at preventing bovine mastitis with a particular focus on Staphylococcus aureus, a bacterium that not only causes mastitis in cattle, but is a leading cause human infection. Vaccine developments for S. aureus in cattle will be compared with research aimed at preventing staphylococcal infection in humans. There are other available vaccines aimed at preventing bovine mastitis serving to illustrate that the goals of vaccination may differ depending on the type of infection being prevented.

Further reading: Vaccine Design: Innovative Approaches and Novel Strategies

Streptococcus pneumoniae Vaccine

2010-06-24T14:52:34+01:00

Vaccines against Streptococcus pneumoniae
from James C. Paton writing in Vaccine Design: Innovative Approaches and Novel Strategies

Existing vaccines against Streptococcus pneumoniae are targeted at the capsular polysaccharide (PS) of which there are 91 distinct serotypes. Polyvalent purified PS vaccines are immunogenic in healthy adults, but not in high risk groups such as young children and the elderly. Development of PS-protein conjugate vaccines has overcome the poor immunogenicity of PS in children, but the protection imparted is strictly serotype-specific, and the number of included serotypes is even more restricted than in the PS vaccine formulations. Widespread introduction of conjugate vaccines in developed countries has dramatically reduced the incidence of invasive pneumococcal disease due to serotypes included in the vaccine. However, these benefits are being eroded by increases in the incidence of disease caused by non-vaccine serotypes. Conjugate vaccines are also expensive, limiting their use in developing countries, where the burden of pneumococcal disease is greatest. Clearly, there is an urgent need to develop alternative pneumococcal vaccines that are (i) inexpensive, (ii) immunogenic in young children, and (iii) provide protection against all pneumococci regardless of serotype. Of particular importance are vaccines comprising pneumococcal proteins that contribute to virulence and are common to all serotypes.

Further reading: Vaccine Design: Innovative Approaches and Novel Strategies | Bacterial Polysaccharides: Current Innovations and Future Trends

Group B Streptococcus Vaccine

2010-06-24T14:49:27+01:00

Toward the Development of a Universal Vaccine Against Group B Streptococcus
from Roberta Cozzi, John L. Telford and Domenico Maione writing in Vaccine Design: Innovative Approaches and Novel Strategies

Group B Streptococcus (GBS) is one of the most common cause of life-threatening bacterial infections in infants and is also an emerging pathogen among adult humans, especially in the elderly, immunocompromised and diabetic adults. Capsular polysaccharide based vaccines of the most common serotypes present in the United States and Europe are in an advanced stage of development but they are not effective against serotypes present in other parts of the world. Many protein antigens have been studied for the discovery of an effective universal vaccine that could overcome serotype specificity. Thanks to reverse vaccinology and new technologies, a vaccine combination based on the pilus proteins has been discovered for the development of a universal GBS vaccine that is potentially capable of preventing all GBS infections.

Further reading: Vaccine Design: Innovative Approaches and Novel Strategies | Pili and Flagella: Current Research and Future Trends

Staphylococcus Vaccines

2010-06-24T14:45:08+01:00

Nosocomial infections: Staphylococcus aureus
from Alice G. Cheng, Olaf Schneewind and Dominique Missiakas writing in Vaccine Design: Innovative Approaches and Novel Strategies

Staphylococcus aureus is the most frequent cause of human skin and soft tissue, bloodstream and respiratory tract infections. Staphylococcal strains have acquired antibiotic resistance traits against available therapies and drug-resistant strains (MRSA, methicillin-resistant S. aureus) are currently isolated in up to 80% of hospital and 60% of community-acquired infections (CA-MRSA). Unlike pneumococci and group A streptococci; S. aureus infections do not raise immunity against subsequent infections. Consistent with this observation, early efforts to develop vaccines from whole-cell killed preparations of staphylococci have failed. More recent work characterized proteins and carbohydrates in the staphylococcal envelope and examined these molecules as protective antigens in vaccine studies. A recent article reviews the pathogenesis of S. aureus infections as well as past and current efforts that have been pursued to develop effective vaccines.

Further reading: Vaccine Design: Innovative Approaches and Novel Strategies | Staphylococcus: Molecular Genetics

Pseudomonas Vaccines

2010-06-24T14:41:53+01:00

Vaccines to Combat Pseudomonas aeruginosa Infections in Immunocompromised Patients
from Jennifer M. Scarff and Joanna B. Goldberg writing in Vaccine Design: Innovative Approaches and Novel Strategies

Pseudomonas aeruginosa is an important opportunistic pathogen that causes an array of nosocomial infections, such as ventilator-associated pneumonia and infections in cancer patients. P. aeruginosa infections are difficult to treat with antibiotics, making the need for other therapeutic options, such as vaccination, critical. The main target antigen for vaccines has been the lipopolysaccharide (LPS) of P. aeruginosa and studies show that vaccination may be partially protective, but that a combination of vaccination with either antibiotic treatment or cell transfusion protocols typically works best. The efficacy of vaccination, particularly against LPS, has been investigated in human cancer patients. These patients were capable of mounting an immune response, but it was often short-lived or accompanied by severe side effects. An anti-Pseudomonas vaccine could be beneficial to aid in treatment of nosocomial infections caused by this bacterium, but would need optimization for better efficacy.

Further reading: Vaccine Design: Innovative Approaches and Novel Strategies | Pseudomonas: Genomics and Molecular Biology

Vaccines for Neglected Diseases

2010-06-24T14:39:18+01:00

Vaccines for Neglected Diseases
from Allan Saul writing in Vaccine Design: Innovative Approaches and Novel Strategies

Infectious diseases exert a major burden of disease in developing countries. While better use of existing vaccines would make an appreciable difference, the greatest burden is caused by diseases for which we currently have no vaccines. The picture, especially in children, is dominated by diarrheal and respiratory diseases. Paradoxically diseases have relatively low priority for funding in absolute terms, and especially in relationship to the burden of disease. Thus, new vaccines for these neglected diseases need both innovative scientific solutions and innovative development schemes involving scientific institutes, public financing and industrial input. The industrial input is critical: not only will vaccine manufacture require an industrial partner, but the knowledge to efficiently undertake the technical and clinical development leading to vaccine production largely resides in industry. A potentially important development in this area has been the recent formation of Industry Linked Vaccine Institutes: For example, The Novartis Vaccines Institute for Global Health and the Hilleman Laboratories. These are an important conduit for applying industrial know how for developing commercial vaccines to the pressing need for vaccines for neglected diseases of developing countries.

Further reading: Vaccine Design: Innovative Approaches and Novel Strategies

Serogroup B Meningococcus Vaccine

2010-06-24T14:35:18+01:00

The First Vaccine Obtained Through Reverse Vaccinology: The Serogroup B Meningococcus Vaccine
from Jeannette Adu-Bobie, Beatrice Aricò, Marzia M. Giuliani and Davide Serruto writing in Vaccine Design: Innovative Approaches and Novel Strategies

Neisseria meningitidis was isolated over one hundred years when Anton Weicshelbaum identified the causative agent of cerebrospinal meningitis. Since its isolation in 1887, N. meningitidis has been recognized to cause endemic cases, case clusters, epidemics and pandemics of meningitis and devastating septicaemia. Despite over one century since its discovery, scientists have yet to identify a universal vaccine for this deadly bacterium. Although vaccines exist for several serogroups of pathogenic N. meningitidis, serotype B (MenB) has eluded scientists for decades, until the advent of genomics. The genome era has completely changed the way to design vaccines. The availability of the complete genome of microorganisms combined with a novel advanced technology has introduced a new prospective in vaccine research. This novel approach is now known as "Reverse Vaccinology" and N. meningitidis can be considered the first successful example of its application. A recent review describes the successful story of the development of the serogroup B vaccine, starting from the analysis of genome and finishing with the results obtained in clinical trials.

Further reading: Vaccine Design: Innovative Approaches and Novel Strategies | Neisseria: Molecular Mechanisms of Pathogenesis

Intralymphatic Vaccination

2010-06-24T14:32:27+01:00

Intralymphatic Vaccination
from Thomas M. Kündig, Pal Johansen, and Gabriela Senti writing in Vaccine Design: Innovative Approaches and Novel Strategies

The immune response is initiated by dendritic cells (DCs) and other antigen-presenting cells. These cells are present in nearly all organs and tissues of the body, so that theoretically any organ or tissue could serve as a route for vaccine administration. The choice of route is therefore mainly based on practical aspects. Using conventional needle and syringe the subcutaneous or intramuscular route are standard. The dermis and especially the epidermis are technically more difficult to target, but are likely to gain more interest due to the recent development of micro-needle patches and needle free injection devices. Vaccine administration via mucosal surfaces such as nasal or oral vaccination represents another option for needle free vaccine administration. While all the above mentioned routes of administration have been proven to work and protect against childhood diseases, influenza and many other infectious agents, the discussion and comparison of these different routes usually focuses on patient convenience, reduction of pain and distress for children, cost and on the possibility for mass vaccination. However, the route of administration can enhance the efficacy of vaccination. Especially in therapeutic vaccination, i.e., in a smaller patient number that already suffers from a disease, vaccination efficiency rather than convenience is the main issue. This is particularly the case in therapeutic cancer vaccines and in allergen specific immunotherapy. Intralymphatic vaccination is a strategy to maximize immunogenicity and therefore vaccine efficacy.

Further reading: Vaccine Design: Innovative Approaches and Novel Strategies

Mucosal Vaccines

2010-06-24T11:24:08+01:00

Mucosal Vaccines
from Rajesh Ravindran and Bali Pulendran writing in Vaccine Design: Innovative Approaches and Novel Strategies

The term "mucosal vaccination" has traditionally been used to describe strategies in which a vaccine is administered via the mucosal route. Unlike parenteral vaccination, mucosal vaccines do not require the use of needles, thus enabling vaccine compliance and reducing logistical challenges and the risks of acquiring blood borne infections. However, despite the great success of mucosal vaccines such as the polio vaccine, several formidable challenges hinder the effective elicitation of immunity against pathogens that invade mucosal sites. First, in humans the mucosal surfaces of the gut, lung, oral cavity and reproductive tracts are estimated to cover an area of 400 square meters, and thus represent the largest portal of entry for pathogens. Second, the acidic environments of many mucosal sites, and the delineation of mucosal sites by the epithelial barrier, pose challenges to the effective delivery of vaccines. Third, the mucosal immune system is faced with a somewhat schizophrenic challenge of having to launch robust immunity against mucosal pathogens, whilst restraining immune reactivity to commensals and food antigens. Fourth, the induction of the appropriate type of immune response is critical for effective protection against different pathogens. Fifth, the accurate quantitation of mucosal T and B cell responses pose unique challenges. Despite these challenges, recent advances in our understanding of the innate immunity and its regulation of adaptive immunity at mucosal sites, are beginning to offer new insights into strategies that result in immune protection at mucosal surfaces. In particular, several recent studies demonstrate that parenteral vaccination with the appropriate adjuvants can induce migration of antigen-specific T and B lymphocytes to mucosal sites. These advances promise to accelerate the development and testing of new mucosal vaccines against many diseases including HIV/AIDS. Most infectious agents that infect humans do so via mucosal sites, principally the digestive, respiratory and genitourinary tracts. Immune defenses at mucosal surfaces therefore constitute a very vital part of the overall protective responses against these invading pathogens. Vaccines that are administered via the oral routes most proficiently induce the mucosal immune responses. In contrast, parenterally administered vaccines are generally poor inducers of mucosal immunity and are therefore less efficient against infections originating at mucosal surfaces (Rajesh Ravindran and Bali Pulendran). However, only a few mucosal vaccines have been approved for human use (Table 1, Rajesh Ravindran and Bali Pulendran)). However, progress in research aimed at understanding the molecular and cellular mechanisms of the mucosal system is presently accelerating, allowing us to design innovative strategies for the development of mucosal vaccines.

Further reading: Vaccine Design: Innovative Approaches and Novel Strategies

Vaccine Adjuvants

2010-06-24T11:20:33+01:00

Vaccine Adjuvants
from David A. G. Skibinski and Derek T. O'Hagan writing in Vaccine Design: Innovative Approaches and Novel Strategies

The development of new effective vaccines, especially those consisting of highly purified antigens, will increasingly require the inclusion of an adjuvant. With over half a century of experience, aluminium containing adjuvants (alum) will continue to be widely used and until very recently remained the only vaccine adjuvant approved for human use in the US. In recent years a number of studies have started to reveal a more detailed understanding of alum's mechanism of action. There is a the need for more potent adjuvants than alum, with particular emphasis on the discovery and development of MF59, an emulsion based vaccine adjuvant which as been licensed for more than ten years in more than 20 countries, for use in an influenza vaccine focused on elderly subjects (Fluad).

Further reading: Vaccine Design: Innovative Approaches and Novel Strategies

Toxin Used in Vaccines

2010-06-24T11:16:38+01:00

Bacterial Protein Toxin Used in Vaccines
from Jerry M. Keith writing in Vaccine Design: Innovative Approaches and Novel Strategies

At first glance, the idea of using protein toxins as vaccines against bacterial human diseases seems somewhat of a paradox. However, in some diseases, the severe pathological effects manifested by the causative agents are mediated entirely by protein toxins. Thus, it seems reasonable to expect that if antibodies could be induced against the protein toxin, they should be effective at preventing severe disease. Of course, the obvious challenge is to detoxify the protein toxin activity without destroying its ability to induce neutralizing antibodies. From an academic point of view, it is ironic that early vaccines against diphtheria, tetanus, and whooping cough were successful without understanding what made them work. One of the keys to this puzzle was uncovered quite by accident when it was discovered that diphtheria toxin stock preparations stored in large earthenware jars too large to be autoclaved were being detoxified by the residual formalin that leached into the preparations from the formalin-sterilized jars. It took two decades for this discovery to be understood and appreciated to a point where formalin-treatment could be applied to produce toxoid preparations for vaccination. It then took another half a century to develop the scientific tools and knowledge needed to bring forth the new generation of vaccines, which are highly effective and less reactogenic. A recent review traces the scientific history, controversies, and development of diphtheria, tetanus, and pertussis vaccines.

Further reading: Vaccine Design: Innovative Approaches and Novel Strategies | Microbial Toxins: Current Research and Future Trends

Glycoconjugate Vaccines

2010-06-24T11:11:15+01:00

New Frontiers in the Chemistry of Glycoconjugate Vaccines
from David R. Bundle writing in Vaccine Design: Innovative Approaches and Novel Strategies

Methods for single point attachment of polysaccharides and oligosaccharides to protein carriers and T-cell peptides are important in vaccine design. Contemporary approaches involve synthetic oligosaccharides with linker or tether chemistry designed for compatibility with synthetic strategies. Current research involves the synthesis and evaluation of conjugate vaccines designed to combat infectious bacterial and fungal diseases, as well as the design and testing of therapeutic cancer vaccine. The prevailing dogma that protective B-cell epitopes should be comprised of 10-20 monosaccharides is confirmed for several experimental vaccines including those directed toward Shigell flexneri and Shigella dysenteriae. However, several small epitopes composed of 3-5 monosaccharide residues are sufficient to induce antibody against the whole organism and to confer protection.

Further reading: Vaccine Design: Innovative Approaches and Novel Strategies

Protective Capacity of Antibodies

2010-06-24T11:06:57+01:00

New Analytical Approaches for Measuring Protective Capacity of Antibodies
from Moon H. Nahm and Carl E. Frasch writing in Vaccine Design: Innovative Approaches and Novel Strategies

Antibodies to the pneumococcal polysaccharide capsule protect the host by opsonizing pneumococci for host phagocytes, while antibodies to the meningococcal polysaccharide capsule protect by directly killing meningococci in the presence of complement. In vitro measurement of serum bactericidal antibody (SBA) against the meningococcus has been used for a long time as a measure of protective immunity. Technical developments of pneumococcal opsonophagocytosis assays (OPA) in the past decade permit measurements of opsonic capacity of sera from persons immunized with pneumococcal vaccines. Experience with OPAs shows that opsonic capacities of antisera are better than their antibody levels in predicting vaccine efficacy. Thus, measurements of opsonic capacity could be a surrogate of clinical studies of pneumococcal vaccines. By being the surrogate for clinical studies, the assays for protective function of antibodies would reduce the need for large clinical trials and facilitate vaccine developments and improvements.

Further reading: Vaccine Design: Innovative Approaches and Novel Strategies

Vaccines in the Era of Genomics

2010-06-24T10:59:48+01:00

Designing Vaccines in the Era of Genomics
from Fabio Bagnoli, Nathalie Norais, Ilaria Ferlenghi, Maria Scarselli, Claudio Donati, Silvana Savino, Michèle A. Barocchi and Rino Rappuoli writing in Vaccine Design: Innovative Approaches and Novel Strategies

Genome sequencing has become routine, and modern vaccine design is taking advantage of the accumulating genomic information. Reverse vaccinology is built on genome-based antigen discovery and has largely replaced classical vaccinology methods based on growing and dissecting the microorganism. The main advantage of the approach is the fast prediction of vaccine candidates. Most of the antigens will be surface exposed proteins, since these antigens are most likely accessible to antibodies. This approach can be applied to non-cultivable microorganisms, something difficult or impossible to do with conventional approaches. When the first reverse vaccinology project was started, in the year 2000, antigen identification was mainly based on bioinformatic analysis of one genome. Since then, the technique has shown its full potential, with the first genome-derived vaccine now in clinical trials and several vaccines in preclinical studies. In the meantime the approach has been improved with the support of proteomics, functional genomics and comparative genomics. The complete process includes antigen prediction to high-throughput purification, screening and selection of the vaccine composition.

Further reading: Vaccine Design: Innovative Approaches and Novel Strategies

Vaccine Strategies

2010-06-24T10:56:24+01:00

Overview of Vaccine Strategies
from Ruth Arnon writing in Vaccine Design: Innovative Approaches and Novel Strategies

There are different strategies applied for vaccination against microbial diseases. These include vaccines against bacterial, viral and parasitic infections which led to tremendous improvement in public health. Both live attenuated or killed whole organisms and their sub-units can be used, as well as more novel approaches, such as DNA vaccines, recombinant vaccines and epitope-based, or peptide vaccines. There are advantages and disadvantages of each approach, eluding to various considerations, such as efficacy, safety and cost of production. The application of passive vaccination, including the use of pooled IgG (IVIG) is also possible. As indicated, these combined strategies led to a long list of vaccines that are presently approved and licensed in the USA, Europe and many other countries. Also important are the pediatric combination vaccines DPT and MMR that are used worldwide, and led to drastic reduction of the incidence of infectious diseases.

Further reading: Vaccine Design: Innovative Approaches and Novel Strategies

Vaccination

2010-06-24T09:24:09+01:00

Vaccination
from Fabio Bagnoli and Rino Rappuoli writing in Vaccine Design: Innovative Approaches and Novel Strategies

Vaccination, together with the wider availability of potable water, has had the most profound positive effect on the quality of public health of any measure: during the past century, these products essentially eliminated most infectious diseases causing mortality in infants and children. Vaccines against diphtheria, tetanus, polio, measles, mumps, rubella, pneumococcus, hepatitis B and meningitis (Haemophilus influenzae and serogroup C meningococcus) have reduced the incidence and mortality of these diseases by > 97-99% (Fabio Bagnoli and Rino Rappuoli). Nevertheless, perception of vaccines in the public opinion is not completely positive. Many people are still skeptical about the real need of vaccines. This behavior has been particularly evident during the influenza A (H1N1) pandemic in 2009.

Further reading: Vaccine Design: Innovative Approaches and Novel Strategies

Conference: Association for General an Applied Microbiology

2010-06-23T13:56:09+01:00

April 3 - 6, 2011 Annual Conference of the Association for General an Applied Microbiology (VAAM)
Karlsruhe, Germany Further information
Main topics: Cell Biology, Environmental Microbiology, Food Microbiology, Microbial Interactions, New Imaging and other innovative Techniques, Stress Responses, White Biotechnology

Suggested reading: Microbiology Books

Conference: Microbes and Industrial Biotechnology

2010-06-23T13:53:38+01:00

November 21 - 24, 2010 ESF-BU-CeBiTec Conference on Microbes and Industrial Biotechnology
Bielefeld, Germany Further information
Chair: Volker Wendisch, Bielefeld University, Institut fur Genomforschung und Systembiologie, DE, Oluf Kruse, Bielefeld University, Center for Biotechnology. Closing date for application is 10th of September, 2010.

Suggested reading: Microbiology Books

Conference: Microscopy, Modeling and Biophysical Methods

2010-06-23T13:50:57+01:00

September 20 - October 2, 2010 Microscopy, Modeling and Biophysical Methods
Heidelberg, Germany Further information
EMBO Practical Course

Suggested reading: Molecular Biology Books

ABC Transporters Book Review

2010-06-22T14:05:08+01:00

I am pleased to provide the following excerpt from a book review of ABC Transporters in Microorganisms:

"of practical use to any scientist working on active transport systems whether in bacteria, parasites, or human cells. It is written in a fashion that allows readers to focus on specific topics and shows comparisons between systems. All the authors are from different disciplines but have contributed their knowledge to a cohesive book ... The book contains some excellent figures of the folding patterns of the proteins and the dynamics of how they change to import or export specific substrates ... well-organized and well-written book ... should be considered an essential reference for laboratories working in this area." from Rebecca T. Horvat (University of Kansas Medical Center, USA) writing in Doodys read more ...

ABC Transporters in Microorganisms

Edited by: Alicia Ponte-Sucre
ISBN: 978-1-904455-49-3
Publisher: Caister Academic Press
Publication Date: August 2009
Cover: hardback

"well-organized and well-written ... an essential reference" (Doodys)

Borrelia Book Review

2010-06-22T12:13:44+01:00

I am pleased to provide the following excerpt from a book review of Borrelia: Molecular Biology, Host Interaction and Pathogenesis:

"This book has 18 chapters and it will cover everything you need to know about these Spirochetes from behaviour in the field to sequencing in a molecular laboratory. Each chapter seems to be written by expert in their Borrelia field and bring updated information about the state-of-art for research of simply general knowledge for this pathogen ... would definitely interest researchers and some teachers seeking research-led examples for their lectures ... this book is a fantastic source of information for scientists working on vector-borne diseases and interested in epidemiology, evolution, genomics ... I truly enjoyed reading this book and would recommend it." from Olivier A E Sparagano (Newcastle University, UK) writing in Parasites and Vectors (2010) 3: 52 read more ...

Borrelia: Molecular Biology, Host Interaction and Pathogenesis

Edited by: D. Scott Samuels and Justin D. Radolf
ISBN: 978-1-904455-58-5
Publisher: Caister Academic Press
Publication Date: March 2010
Cover: hardback

"a fantastic source of information" (Parasites and Vectors)

Salmonella and Cancer

2010-06-16T15:58:30+01:00

Salmonella as the paradigm for bacterial therapy of cancer: A progress report
from Robert M. Hoffman writing in Salmonella: From Genome to Function

For over 300 years it has been observed that cancer patients who became infected with bacteria sometimes experienced spontaneous remission of their cancer. Recently, there have been attempts to develop cancer treatments by using tumor-targeting bacteria. Anaerobic microorganisms, such as Clostridium, that preferentially grow in necrotic tumor areas have mostly been used. However, the resulting tumor killing was, at best, limited. Salmonella was originally developed as an antitumor agent by attenuating the bacteria with multiple mutations, including auxotrophs. These multiple auxotrophs appeared to direct the bacteria to the metastatic areas of tumors where more nutrients are available. We have developed a more effective bacterial cancer therapy strategy by targeting viable tumor tissue with Salmonella enterica serovar Typhimurium containing only two auxotrophic mutations. These auxotrophs grow in viable as well as necrotic areas of tumors. However, the auxotrophy severely restricts growth of these bacteria in normal tissue, making this a safe treatment. The S. Typhimurium A1-R mutant, which is auxotrophic for leucine and arginine and had been selected for high antitumor virulence, was effective as monotherapy against human prostate and breast tumors that had been orthotopically implanted in nude mice. The approach described here, where bacterial monotherapy effectively treats primary and metastatic tumors, is a significant improvement over previous bacterial tumor-therapy strategies that require combination with toxic chemotherapy. Exploitation of the tumor-killing capability of Salmonella has great potential for a new paradigm of cancer therapy.

Further reading: Salmonella: From Genome to Function

Salmonella Biofilms

2010-06-16T15:51:09+01:00

Salmonella Biofilms: From food to human disease
from Robert W. Crawford, Geoffrey Gonzalez-Escobedo and John S. Gunn writing in Salmonella: From Genome to Function

Bacterial biofilms are increasingly implicated as burdens to food and public safety. Over the past few decades, we have learned that this sessile environment provides diverse species of bacteria selective advantages in natural, medical, and industrial ecosystems, as well as resistance to commonly administered antibiotics and protection from host immune responses during chronic infection of humans and animals. Salmonella spp. are food-borne pathogens that remain a critical health concern in impoverished and industrialized nations. In the laboratory, salmonellae have been shown to form biofilms on a variety of surfaces. These Salmonella spp. biofilms have been found to contaminate plant and animal food sources to cause human disease upon consumption, and/or to enhance salmonellae colonization of and persistence at sites of infection.

Further reading: Salmonella: From Genome to Function

Anti-Salmonella immunity

2010-06-16T15:47:30+01:00

Anti-Salmonella immunity: Highlighting new research in vaccines, mucosal immunology and systemic disease
from Jennifer L. Bishop, Ellen T. Arena, Kenneth W. Harder and B. Brett Finlay writing in Salmonella: From Genome to Function

Enteric fever and non-typhoidal salmonelloses (NTS) are caused by a wide variety of Salmonella enterica serovars and are a serious health threat throughout the world. Immunity to systemic typhoid and NTS requires intricate crosstalk between both innate and adaptive immune cells spanning multiple organ systems. The development of a number of new mouse and in vitro culture models suitable for studying gastroenteritis has highlighted the complexity of mucosal responses and shown how a diverse subset of cells interact within the intestinal architecture to elicit anti-Salmonella immunity. These include specific dendritic cell subsets, natural killer cells and TH17 skewed T helper cells and the repertoire of cytokines they produce, including IL-17, IL-23, IL-22 and IL-15. Furthermore, the importance of commensal microflora has been stressed in various Salmonella models, and new research has shown the various effects of prebiotics, probiotics and antibiotics on Salmonella pathogenesis. Systemic immune responses are also more explicitly understood, as the location and phenotype of cells harboring intracellular bacteria become more defined. A forthcoming book reviews these recent advances and how they are being translated into new therapies and vaccine studies in the human population.

Read more: Salmonella: From Genome to Function

The Intracellular lifestyle of Salmonella

2010-06-16T15:44:14+01:00

The intracellular lifestyle of Salmonella enterica and novel approaches to understand the adaptation to life within the Salmonella-containing vacuole
from Roopa Rajashekar and Michael Hensel writing in Salmonella: From Genome to Function

Salmonella enterica is a facultative intracellular pathogen that resides in a unique membrane-bound compartment, referred to as Salmonella-containing vacuole or SCV. Within the SCV, Salmonella is able to survive the antimicrobial activities of phagocytic cells and can rapidly multiply in a variety of host cells. Intracellular life of Salmonella is dependent on a large number of virulence traits, but the function of the type III secretion system (T3SS) encoded by Salmonella Pathogenicity Island 2 (SPI2) is of central importance. Although more than 20 effector proteins have been identified as translocated by the SPI2-T3SS, the molecular function and contribution to intracellular live is only known for a few of these proteins. Intracellular Salmonella modify basic functions of the host cell such as the structure of the microtubule cytoskeleton and induce a massive reorganization of vesicular transport and the endosomal system. Unique phenomena are the SPI2-dependent induction of extensive tubular membrane aggregations of endosomal or Golgi-derived vesicles. The SCV itself has features of a novel organelle and the fate of this compartment is controlled by the pathogen. Previous observations indicated that the SCV is arrested in the state of late endosomal compartment, but recent studies using advanced ultrastructural analyses and live cell studies indicate a complex and highly dynamic interaction of the intracellular Salmonella and their host cells.

Further reading: Salmonella: From Genome to Function

Salmonella virulence factors

2010-06-16T15:38:01+01:00

Salmonella secreted virulence factors
from Fred Heffron, George Niemann, Hyunjin Yoon, Afshan Kidwai, Roslyn Brown, Jason McDermott, Richard Smith and Joshua Adkins writing in Salmonella: From Genome to Function

Research in the past twenty years has shown that Salmonella precisely manipulates their host by hierarchical secretion of virulence factors (effectors). More than 40 secreted virulence factors have been identified in Salmonella, but the function and mammalian targets of only a few are known. Effectors are directed to specific sub-cellular compartments and mammalian targets, and they mediate a diverse array of activities. Thus, the first half of this review focuses upon our understanding of effector mechanisms and their roles during infection.

However, the known effector repertoire is incomplete and the second half of this review places an emphasis on discovery. Computer analysis identified common secretion motifs and predicted that as many as 300 additional proteins may be secreted by Salmonella. In fact, mass spectrometry analysis identified a more complete secretome and found many novel, uncharacterized effector proteins. Several effectors identified in this study were small proteins of only 30-100 amino acids in length, suggesting that they are not enzymes but agonists or antagonists of specific host factors. One surprise from the mass spectrometry analysis was the identification of proteins that are secreted to mammalian cells via outer membrane vesicles. Complete characterization of the bewildering array of secreted proteins will take many years.

Further reading: Salmonella: From Genome to Function | Bacterial Secreted Proteins

Flagella of Salmonella

2010-06-16T15:34:54+01:00

New insights into the role and formation of flagella in Salmonella
from Rasika M. Harshey writing in Salmonella: From Genome to Function

The flagellum of Salmonella enterica serovar Typhimurium is the best studied of all flagellar systems. The major function of the flagellum is to enable swimming and chemotaxis in liquid media, and swarming on surfaces. New structural information, along with biochemical, physicochemical and genetic analyses has greatly accelerated our understanding of the self-assembly of this highly sophisticated nano-machine. The study of swarming motility is a relatively new field, but has begun to reveal new roles for the flagellum, new functions for motility genes and new regulatory circuits that control the decision between motility and sessility. Morphological and functional similarities between flagella and needle complexes, discovery of partial flagellar structures that likely function in export rather than motility, and a rapidly accumulating genome database are gradually illuminating the evolutionary origins of the flagellum.

Further reading: Salmonella: From Genome to Function | Pili and Flagella

Fimbriae of Salmonella

2010-06-16T15:30:37+01:00

Fimbrial signature arrangements in Salmonella
from Sean-Paul Nuccio, Nicholas R. Thomson, Maria C. Fookes and Andreas J. Bäumler writing in Salmonella: From Genome to Function

The complement of fimbrial operons held within a genome represents one of the key differentiating features of the sequenced Salmonella serovars and one of the single largest sources of genetic diversity. Generically described as filamentous non-flagellar surface appendages, fimbriae (also known as pili) typically imbue an adhesive trait to the cells expressing them. While much is known about the general biology of fimbrial assembly mechanisms, the role of these structures in Salmonella pathogenesis remains poorly characterized. Here we present fimbrial operon data gathered from the seventeen completed Salmonella genome sequences and discuss its implications in Salmonella pathogenesis and dissemination.

Further reading: Salmonella: From Genome to Function | Pili and Flagella

Small RNAs of Salmonella

2010-06-16T15:26:25+01:00

The small RNAs of Salmonella
from Sridhar Javayel, Kai Papenfort and Jörg Vogel writing in Salmonella: From Genome to Function

To date, close to one hundred distinct small noncoding RNAs (sRNAs) have been identified in Salmonella by a variety of biocomputational or wet-lab approaches including RNA sequencing. The function of more than twenty of these sRNAs is known from studies in Salmonella itself or can be inferred from conserved homologs in E. coli Many of these sRNAs act in conjunction with the RNA-chaperone Hfq to post-transcriptionally repress or activate trans-encoded target genes, but cis-antisense RNAs and regulators of protein activity are also abundantly present. In addition to a large number of sRNAs conserved in other enteric bacteria, Salmonella also expresses a set of sRNAs specific to this genus. Interestingly, such regulators have been shown to control the expression of conserved genes encoded on the "core" Salmonella genome. Conversely, conserved sRNA can act as regulators of recently acquired Salmonella-specific genes, indicating significant cross-talk of conserved and horizontally acquired elements at the RNA level. A recent review covers strategies for the identification of sRNAs as well as their characterized functional roles in Salmonella.

Further reading: Salmonella: From Genome to Function | RNA and the Regulation of Gene Expression

Genomics and Pathogenesis of Salmonella

2010-06-16T14:55:29+01:00

Genomics and Pathogenesis of Salmonella enterica serovars Typhi and Paratyphi A
from Kathryn E Holt, Tim T Perkins, Gordon Dougan and Robert A Kingsley writing in Salmonella: From Genome to Function

The genomics era has transformed the way that we can study bacterial pathogens. The availability of two complete and 17 draft genomes of S. Typhi has made it possible to study the phylogenetic structure of this pathogen in unparalleled resolution, monitor gene flux, accumulation of pseudogenes, neutral mutations and loci under selective pressure. We describe the molecular basis of Salmonella Typhi pathogenesis, in particular where genomics has contributed to our understanding in the past decade. Potentially important S. Typhi-specific virulence determinants include the Vi polysaccharide capsule, the type IV pilus, and a unique repertoire of fimbria. These may account for key differences in the disease outcome of this pathogen compared with non-typhoidal serotypes. Genome comparison with the closely related serotype S. Paratyphi A identifies a core set of pseudogenes, some of which emerged independently, that may define important features of genome degradation associated with host restriction and pathogenesis of invasive disease. Geo-phylogenetics of S. Typhi constructed from single nucleotide polymorphism data from high throughput draft genome sequences is now being applied to study molecular epidemiology in the field.

Further reading: Salmonella: From Genome to Function

Salmonella evolution

2010-06-16T14:50:54+01:00

Evolutionary trends associated with niche specialization as modeled by whole genome analysis of egg-contaminating Salmonella enterica serovar Enteritidis
from Jean Guard, Devendra Shah, Cesar A. Morales and Doug Call writing in Salmonella: From Genome to Function

The mosaic nature of the Salmonella enterica genome facilitates its access to multiple environments. Many large scale genomic events have been described that contribute to the combinatorial complexity of the pathogenic Salmonellae. However, the impact of small scale genetic change occurring at the level of single nucleotide polymorphism (SNP) on the emergence of niche specialization is just now becoming appreciated. A recent review describes concepts behind the evolution that culminated in the remarkable ability of Salmonella enterica serovar Enteritidis to contaminate and survive in the internal content of eggs produced by otherwise healthy hens. Evidence suggests that combinations of SNPs facilitate niche specialization by Salmonella enterica. However, few typing methods incorporate unbiased strategies for their detection. Selection of appropriate biological assays for ranking SNPs and combinations of SNPs for their impact on the ability of Salmonella enterica to propagate outbreaks, pandemics and disease will be a significant challenge to improve the safety of the food supply.

Further reading: Salmonella: From Genome to Function

Salmonella survival

2010-06-16T11:58:10+01:00

High-throughput screening to determine the genetic requirements for Salmonella survival under different growth conditions
from Mollie Megan Reynolds, Rocio Canals, Michael McClelland and Helene Andrews-Polymenis writing in Salmonella: From Genome to Function

Salmonella species are capable of survival in a wide range of niches, both in the environment and in an infected host. Genetic requirements for survival of Salmonella in different niches have traditionally been identified using gene expression and forward genetics. The availability of complete genome sequences, microarray technology, and cost-effective new sequencing capabilities enabled increasingly efficient high-throughput analyses of Salmonella genomes to identify elements that contribute to survival in these niches. A recent review describes many of the high-throughput tools that have been developed over the past two decades, and the genetic requirements for Salmonella survival that have been identified using these techniques.

Further reading: Salmonella: From Genome to Function

Salmonella genomes

2010-06-16T11:51:37+01:00

Comparison of Salmonella genomes
from Ye Feng, Wei-Qiao Liu, Kenneth E. Sanderson, and Shu-Lin Liu writing in Salmonella: From Genome to Function:

Salmonella contains over 2600 known lineages, each with distinct biological characteristics, including differences in the niche in which they dwell and the nature of diseases they may cause in their hosts. Genomic sequence analysis is beginning to reveal the genetic basis that determines the phenotypic differences among them. Comparison of eight sequenced genomes of Salmonella subgroup I lineages, which infect warm-blooded animals including humans, demonstrates that these pathogens share about 90% of their genes (the "core" genome), with the remaining ca. 10% genes being unique to each of the lineages (the "accessory" genome). Prophages and Salmonella Pathogenicity Islands (SPIs) are the main components of the accessory genome. Insertion of large DNA segments, such as SPI7 in S. Typhi, may disrupt physical balance of the genome between replication origin and terminus and rearrangements of the genome, such as inversions or translocations mediated by homologous sites (rrn operons, prophages, IS200, etc.) may accelerate rebalancing of the genome. Laterally transferred genes are the main driving force in Salmonella evolution and speciation; evidence exists indicating that mismatch repair genes may spontaneously regulate bacterial mutability through allele conversion to facilitate or inhibit incorporation of foreign DNA. Further studies may help elucidate the genetic basis of distinct pathogeneses and host ranges among the Salmonella pathogens.

Further reading: Salmonella: From Genome to Function

Phages of Salmonella

2010-06-16T11:47:04+01:00

Typing phages and prophages of Salmonella
from Wolfgang Rabsch, Sandra Truepschuch, Daniel Windhorst and Roman G. Gerlach writing in Salmonella: From Genome to Function:

Most Salmonella strains contain prophages or remnant phages and release them spontaneously. Special bacteriophages were developed and used in phage typing systems for epidemiological work all over the world since 1947 to control salmonellosis. This method provides fast and inexpensive characterization of frequent serovars such as S. Typhimurium or S. Typhi on the sub-serovar level and is especially useful for primary analysis before investigation by other, more expensive molecular techniques such as sequencing. Prophages are themselves not only variable elements in a chromosome but also variable by module exchange within the prophage genome, thus providing a high discriminating power. The availability of several genome sequences of different Salmonella serovars has recently led to the identification of new prophage-like elements. The prophages present in serovars Typhimurium, Enteritidis and Typhi are discussed. Salmonella phages frequently carry foreign DNA, so called morons. These morons are not necessary for phage functions but provide a benefit for the host. A list of some new morons found in different Salmonella serovars is presented. Recently, a monophasic variant of S. Typhimurium mainly belonging to Anderson phage type DT193 has become one of the dominant causes of salmonellosis in Germany and other European countries. These strains with the antigenic formula 4,[5],12:i:- do not express the 2^nd phase flagellum. Investigation of their prophage attachment sites showed that the sites for Gifsy-1, Gifsy-2 and ST64B were occupied by the respective prophages. In about 90% of the monophasic DT193 strains the P22/ST64T attachment site was occupied by a novel 18.4 kb fragment, containing several open reading frames with significant similiarity to phage-related genes.

Further reading: Salmonella: From Genome to Function | Bacteriophage: Genetics and Molecular Biology

Salmonella classification

2010-06-16T11:41:26+01:00

New approaches in sub-species level Salmonella classification
from Burkhard Malorny, Elisabeth Hauser and Ralf Dieckmann writing in Salmonella: From Genome to Function:

Salmonellae form a complex group of bacteria consisting of two species, 6 subspecies and more than 2,500 serovars (serotypes). Salmonella identification below species level is most often limited to phenotypic typing methods such as biochemical and serological identification, which are costly, time-consuming and do not always reflect the evolution of Salmonella groups. Newer methods for Salmonella typing and subtyping include genome-based methods such as pulsed field gel electrophoresis (PFGE), Multiple Loci VNTR Analysis (MLVA), Multilocus sequence typing (MLST) and (multiplex-) PCR-based methods. In the last years further molecular typing technologies were evaluated for this purpose. A recent review discusses some of these emerging technologies and gives an outlook on future developments with a focus on oligonucleotide microarrays, spectroscopic methods such as MALDI-TOF mass spectrometry and special developments such as bead-based suspension arrays using Luminex technology and DNA sequence-based approaches. These new techniques promise significant advantages compared to traditional culture-based methods with respect to speed, ease of use, reliability and automation.

Further reading: Salmonella: From Genome to Function

PCR Optimization Strategies

2010-06-15T15:55:50+01:00

RT-PCR Optimization Strategies
from Martina Reiter and Michael W. Pfaffl writing in PCR Troubleshooting and Optimization: The Essential Guide

PCR technology is based on a simple principle; an enzymatic reaction that increases the amount of nucleic acids initially present in a sample but this powerful method makes it possible to detect specific mRNA transcripts in any biological sample by the application of RT-PCR. The RT-PCR quantitative analysis workflow has several steps, each of which is crucial to the success of the experiment. It starts with a sampling step, followed by nucleic acid extraction and stabilization, cDNA synthesis and finally the qPCR where the mRNA quantification takes place. PCR itself is quite a stable reaction with reproducibility between 2-8% but the number and nature of the pre-PCR steps mean that there are many sources of experimental variance in the workflow. Reliable data can only be produced when the experimental variance is minimized, so the sources of variation must be identified and optimized for each step of each experiment. Typically, however, the pre-PCR steps are neglected and optimization is done for PCR reaction only. Optimization of the whole RT-PCR workflow is important and recommendations to reduce experimental variance and produce more reproducible and reliable results should be followed.

Further reading: PCR Troubleshooting and Optimization: The Essential Guide

Calicivirus book

2010-06-08T15:49:47+01:00

The new book on Caliciviruses: Molecular and Cellular Virology edited by Grant S. Hansman, Xi Jason Jiang and Kim Y. Green has been published and is available from library suppliers and bookshops read more ...

Caliciviruses: Molecular and Cellular Virology

Edited by: Grant S. Hansman, Xi Jason Jiang and Kim Y. Green
ISBN: 978-1-904455-63-9
Publisher: Caister Academic Press
Publication Date: April 2010
Cover: hardback

International Symposium on Soil Metagenomics

2010-06-08T08:55:33+01:00

December 8 - 10, 2010 International Symposium on Soil Metagenomics
Braunschweig, Germany Further information

The objective and challenge of this Symposium is to open our minds to the new potentials of next generation sequencing, to question our traditional approaches, and to explore and discuss how we can utilize those novel datasets. Which questions can we now dare to address in soil ecology and how can we approach the problems of scales to further unveil the secrets of the huge microbial biodiversity that we find on Earth? Discussions at the launch of a new leap forward in soil microbiology and ecology.
Suggested reading:
Streptomyces: Molecular Biology and Biotechnology
Metagenomics: Theory, Methods and Applications

Conference Alert: The Non-Coding Genome

2010-06-08T08:55:05+01:00

October 13 - 16, 2010 The Non-Coding Genome
Heidelberg, Germany Further information

This symposium will provide an interdisciplinary discussion of the roles of non-coding RNAs with the aim of enhancing our understanding of gene regulation and function. Topics will include recent discoveries in the fields of prokaryotic and eukaryotic long and short non-coding RNAs. The functional roles of non-coding RNAs in a wide variety of cell processes will be discussed.
Suggested reading: RNA Interference and Viruses: Current Innovations and Future Trends

German Society for Immunology Conference

2010-06-08T08:54:16+01:00

September 22 - 25, 2010 40th Annual Meeting of the German Society for Immunology (DGfI)
Leipzig, Germany Further information

Annual Meeting of the German Society for Immunology. Symposia and workshops. Topics include Basic Immunology, Applied Immunology, Interventional Immunology. Conference chair is Prof. Dr. Frank Emmrich.
Suggested reading: Microbiology Books

Conference: Microbes in Industry and Environment

2010-06-08T08:53:27+01:00

September 22 - 25, 2010 Power of Microbes in Industry and Environment 2010
Malinska, Croatia Further information

Power of microbes in industry and environment. Organized by the Croatian, Hungarian and Slovenian microbiological societies and supported by FEMS.
Suggested reading: Environmental Microbiology Books

International Conference on Diseases in Nature Communicable to Man

2010-06-08T08:52:40+01:00

August 8 - 10, 2010 International Conference on Diseases in Nature Communicable to Man
Fairbanks, Alaska, USA Further information

The annual International Conference on Diseases in Nature Communicable to Man seeks to increase knowledge and awareness of zoonotic disease within the medical and public health communities. INCDNCM conferences are multidisciplinary, including presentations on viral, rickettsial, bacterial, parasitic, and prion-related diseases acquired from natural sources, including animals (wild or domestic), contaminated water or food supplies, arthropod vectors and other sources. Submitted presentations are typically 10-15 minutes in length and can describe epidemiological, clinical, ecological, diagnostic or laboratory-related aspects of the above diseases. Student presentations are encouraged. The R.R. Parker Memorial Lecture, presented during the banquet, features an invited specialist in an aspect of zoonotic disease.
Suggested reading: Anaerobic Parasitic Protozoa: Genomics and Molecular Biology

MIQE Guidelines Uncloaked

2010-06-07T18:43:48+01:00

No matter how good you are at PCR, you can always learn something from the speakers we have lined up for our Getting the most out of PCR live online seminar series. These guy eat, sleep and drink PCR.

Next up we have MIQE Guidelines Uncloaked, in which Greg Shipley will give you the inside track on the requirements you need to satisfy to make sure your PCR results are suitable for publication. You'd be mad to miss it.

This event goes out live tomorrow (Tue 8th June) at 9am Pacific / 12pm Eastern / 5pm BST (UK) / 6pm CET. Click here to secure one of the remaining places on this live event.

You can also click here to take a look at our archive for this series, which now contains:

Magic in Solution: An Introduction and Brief History of PCR
Speaker: Carl Wittwer

Obtaining Maximum PCR Sensitivity and Specificity
Speaker: Cameron N. Gundry Attendence: 125

Significance of Controls and Standard Curves in PCR
Speaker: Ian Kavanagh

Microbial Toxin Book Review

2010-06-07T18:43:12+01:00

I am pleased to provide the following excerpt from a book review of Microbial Toxins: Current Research and Future Trends:

"the book serves well the molecular microbiologist ... not only well-documented but timely and inspiring" from Robert D. Johnson (St. George's University, NJ, USA) writing in Inoculum (2010) 61: 21-22 read more ...

Microbial Toxins: Current Research and Future Trends

Edited by:
ISBN: 978-1-904455-44-8
Publisher: Caister Academic Press
Publication Date: May 2009
Cover: hardback

"timely and inspiring" (Mycological Society)

Lentivirus Book Review

2010-06-07T18:42:29+01:00

I am pleased to provide the following excerpt from a book review of Lentiviruses and Macrophages: Molecular and Cellular Interactions:

"excellent and comprehensive ... the reference lists of virtually all chapters are remarkably up-to-date ... this volume is highly recommended to virologists, molecular biologists, immunologists, epidemiologists and infectious disease physicians." from Ulrich Desselberger (Cambridge, UK) writing in Microbiology Today read more ...

Lentiviruses and Macrophages: Molecular and Cellular Interactions

Edited by: Moira Desport
ISBN: 978-1-904455-60-8
Publisher: Caister Academic Press
Publication Date: March 2010
Cover: hardback

"highly recommended" (Microbiology Today)

RNA Interference Book Review

2010-06-07T18:41:52+01:00

I am pleased to provide the following excerpt from a book review of RNA Interference and Viruses: Current Innovations and Future Trends:

"This book provides a comprehensive review of the interface between RNA interference and viruses. It lives up to its title by being commendably up-to-date for a multi-author compilation of this type ... excellent and engaging" from Laurence Tiley (University of Cambridge, UK) writing in Microbiology Today read more ...

RNA Interference and Viruses: Current Innovations and Future Trends

Edited by: Miguel Angel Martínez
ISBN: 978-1-904455-56-1
Publisher: Caister Academic Press
Publication Date: February 2010
Cover: hardback

"a comprehensive review" (Microbiology Today)

Neisseria Book Review

2010-06-07T18:41:12+01:00

I am pleased to provide the following excerpt from a book review of Neisseria: Molecular Mechanisms of Pathogenesis:

"focuses effectively on (the) molecular approach to neisserial pathogenicity ... authoritative reviews of gene regulation, anaerobic survival, genome plasticity, epidemiology, vaccine development and the development of antibiotic resistance ... well-referenced" from Jeff Cole (University of Birmingham, UK) writing in Microbiology Today read more ...

Neisseria: Molecular Mechanisms of Pathogenesis

Edited by: Caroline Genco and Lee Wetzler
ISBN: 978-1-904455-51-6
Publisher: Caister Academic Press
Publication Date: January 2010
Cover: hardback

"authoritative reviews" (Microbiology Today)

Aspergillus book review

2010-06-07T18:40:25+01:00

I am pleased to provide the following excerpt from a book review of Aspergillus: Molecular Biology and Genomics:

"a readable but authoritive overview of current knowledge and approaches ... Its approach is firmly post-genomic, emphasizing the new insights that can be gained ... This book will be a good institutional purchase to support advanced teaching but also for personal or laboratory purchase for researchers within industry." from Meriel G. Jones (University of Liverpool, UK) writing in Microbiology Today read more ...

Aspergillus: Molecular Biology and Genomics

Edited by: Masayuki Machida and Katsuya Gomi
ISBN: 978-1-904455-53-0
Publisher: Caister Academic Press
Publication Date: January 2010
Cover: hardback

"authoritive overview" (Microbiology Today)

Dengue Review

2010-06-07T15:51:54+01:00

I am pleased to provide the following excerpt from a book review of Frontiers in Dengue Virus Research:

"The book presents the reader with a complete account of Dengue fever in a generally well-organized and informative, yet highly accessible manner ... this is a thorough and up-to-date account of dengue history, progression and current research. In addition to being an accessible source for those new to the field, this book will surely be a valuable point of reference for those who are fully immersed in it." from David Sharpley (University of Liverpool, UK) writing in Microbiology Today read more ...

Frontiers in Dengue Virus Research

Edited by: Kathryn A. Hanley and Scott C. Weaver
ISBN: 978-1-904455-50-9
Publisher: Caister Academic Press
Publication Date: January 2010 Available now!
Cover: hardback

"a valuable point of reference" (Microbiology Today)

Flagella Review

2010-06-07T15:41:32+01:00

I am pleased to provide the following excerpt from a book review of Pili and Flagella: Current Research and Future Trends:

"The Editor has sought chapters for this excellent book from leaders in their respective fields, and he brings together functionality of flagella and pili, as well as their evolution and in the case of flagella, their application as heterologous expression systems. I cannot think of another book that is such a \'one-stop shop\' for such topics gathered together ... the authors write with enthusiasm and authority ... a great purchase for an institutional library or large bacterial research lab." from Elizabeth Sockett (University of Nottingham, UK) writing in Microbiology Today read more ...

Pili and Flagella: Current Research and Future Trends

Edited by: Ken Jarrell
ISBN: 978-1-904455-48-6
Publisher: Caister Academic Press
Publication Date: August 2009 Available now!
Cover: hardback

"excellent book" (Microbiology Today)

Protozoa Book Review

2010-06-07T14:56:33+01:00

I am pleased to provide the following excerpt from a book review of Anaerobic Parasitic Protozoa: Genomics and Molecular Biology:

"beautifully produced and attractively packaged hardbound book of authoritative edited reviews ... very well written and edited and so is easy to read even for non-specialists." from Kevin M. Tyler (University East Anglia, Norwich) writing in Parasites and Vectors (2010) 3: 45 read more ...

Anaerobic Parasitic Protozoa: Genomics and Molecular Biology

Edited by: C. Graham Clark, Patricia J. Johnson and Rodney D. Adam
ISBN: 978-1-904455-61-5
Publisher: Caister Academic Press
Publication Date: March 2010
Cover: hardback

"very well written" (Parasites and Vectors)

Streptomyces book

2010-06-07T12:18:13+01:00

Paul Dyson (Institute of Life Sciences, School of Medicine, Swansea, UK) presents a new book on Streptomyces: Molecular Biology and Biotechnology
Streptomycetes are Gram-positive, high GC-content, sporulating bacteria found predominantly in soil. Streptomycetes are characterised by a complex secondary metabolism producing antibiotic compounds and other metabolites with medicinal properties. In recent years genomic studies, genomic mining and biotechnological approaches have been employed in the search for new antibiotics and other drugs.
With contributions from some of the leading scientists in the field, this volume documents recent research and development in streptomycetes genomics, physiology and metabolism. With a focus on biotechnology and genomics, the book provides an excellent source of up-to-date information. Topics include: genome architecture, conjugative genetic elements, differentiation, protein secretion, central carbon metabolic pathways, regulation of nitrogen assimilation, phosphate control of metabolism, gamma-butyrolactones and their role in antibiotic regulation, clavulanic acid and clavams, genome-guided exploration, gene clusters for bioactive natural products, genomics of cytochromes p450.

Streptomyces: Molecular Biology and Biotechnology

Edited by: Paul Dyson
ISBN: 978-1-904455-77-6
Publisher: Caister Academic Press
Publication Date: January 2011
Cover: hardback

Essential reading for research scientists, biotechnologists, graduate students and other professionals involved in streptomycetes research, antibiotic and antimicrobial development, drug discovery, soil microbiology and related fields. A recommended text for all microbiology laboratories.

Alphaherpesviruses book

2010-06-04T15:37:41+01:00

Sandra K. Weller (Board of Trustees Distinguished Professor and Chair of Molecular, Microbial and Structural Biology, Dept Microbiology, University of Connecticut Health Center, Farmington Avenue, Farmington, CT , USA) presents a new book on Alphaherpesviruses: Molecular Virology

Alphaherpesviruses are a fascinating group of DNA viruses that includes important human pathogens such as herpes simplex virus type 1 (HSV-1), HSV-2, and varicella-zoster virus (VZV): the causative agents of cold sores, genital ulcerous disease, and chickenpox/shingles, respectively. A key attribute of these viruses is their ability to establish lifelong latent infection in the peripheral nervous system of the host. Such persistence requires subversion of the host's immune system and intrinsic antiviral defense mechanisms. Understanding the mechanisms of the immune evasion and what triggers viral reactivation is a major challenge for today's researchers. This has prompted enormous research efforts into understanding the molecular and cellular biology of these viruses.

This up-to-date and comprehensive volume aims to distill the most important research in this area providing a timely overview of the field. Topics covered include: transcriptional regulation, DNA replication, translational control, virus entry and capsid assembly, the role of microRNAs in infection and oncolytic vectors for cancer therapy. In addition there is coverage of virus-host interactions, including apoptosis, subversion of host protein quality control and DNA damage response pathways, autophagy, establishment and reactivation from latency, interferon responses, immunity and vaccine development. Essential reading for everyone working with alphaherpesviruses and of interest to all virologists working on latent infections.

Alphaherpesviruses: Molecular Virology

Edited by: Sandra K. Weller
ISBN: 978-1-904455-76-9
Publisher: Caister Academic Press
Publication Date: March 2011
Cover: hardback

Plant Virology

2010-06-04T15:36:27+01:00

Carole Caranta, Miguel A. Aranda, Mark Tepfer and J.J. Lopez-Moya (INRA-UR , Génétique et Amélioration des Fruits et Légumes, Montfavet cedex, France;Centro de Edafología y Biología Aplicada del Segura (CEBAS), CSIC, Espinardo, Murcia, Spain;Laboratoire de Biologie Cellulaire, INRA, F Versailles Cedex, France;IBMB, Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB, Barcelona, Spain, respectively) present a new book on Recent Advances in Plant Virology

Viruses that infect plants are responsible for reduction in both yield and quality of crops around the world, and are thus of great economic importance. This has provided the impetus for the extensive research into the molecular and cellular biology of these pathogens and into their interaction with their plant hosts and their vectors. However interest in plant viruses extends beyond their ability to damage crops. Many plant viruses, for example tobacco mosaic virus, have been used as model systems to provide basic understanding of how viruses express genes and replicate. Others permitted the elucidation of the processes underlying RNA silencing, now recognised as a core epigenetic mechanism underpinning numerous areas of biology.

This book attests to the huge diversity of research in plant molecular virology. Written by world authorities in the field, the book opens with two chapters on the translation and replication of viral RNA. Following chapters cover topics such as viral movement within and between plants, plant responses to viral infection, antiviral control measures, virus evolution, and newly emerging plant viruses. To close there are two chapters on biotechnological applications of plant viruses. Throughout the book the focus is on the most recent, cutting-edge research, making this book essential reading for everyone, from researchers and scholars to students, working with plant viruses.

Recent Advances in Plant Virology

Edited by: Carole Caranta, Miguel A. Aranda, Mark Tepfer and J.J. Lopez-Moya
ISBN: 978-1-904455-75-2
Publisher: Caister Academic Press
Publication Date: February 2011
Cover: hardback

Bacterial Histone-Like HU Proteins

2010-05-20T13:58:39+01:00

Bacterial histone-like HU proteins are critical to maintenance of the nucleoid structure. In addition, they participate in all DNA-dependent functions, including replication, repair, recombination and gene regulation. Their function is typically architectural, inducing a specific DNA topology that promotes assembly of higher-order nucleo-protein structures.

Although HU proteins are highly conserved, individual homologs have been shown to exhibit a wide range of different DNA binding specificities and affinities. The existence of such distinct specificities indicates functional evolution and predicts distinct in vivo roles. Emerging evidence suggests that HU proteins discriminate between DNA target sites based on intrinsic flexure, and that two primary features of protein binding contribute to target site selection: The extent to which protein-mediated DNA kinks are stabilized and a network of surface salt-bridges that modulate interaction between DNA flanking the kinks and the body of the protein.

These features confer target site selection for a specific HU homolog, they suggest the ability of HU to induce different DNA structural deformations depending on substrate, and they explain the distinct binding properties characteristic of HU homologs. Further divergence is evidenced by the existence of HU homologs with an additional lysine-rich domain also found in eukaryotic histone H1.

Further reading: Functional Evolution of Bacterial Histone-Like HU Proteins

Conference Update

2010-05-17T15:45:59+01:00

September 18 - 23, 2011 WaterMicro 2011
Rotorua, New Zealand Further information
16th International Symposium on Health-Related Water Microbiology, Sub-Group of the International Water Association. Topics include: Water pollution and diseases; Microbial source tracking; Catchment protection; Biofilm studies; Water and sanitation in developing country; Climate change and water quality; Recreational water and health; Epidemiology of waterborne diseases; Microbial risk assessment; Microbial quality of shellfish growing areas, Applications of nanotechnology; Water and energy; Zoonoses.
Suggested reading: Environmental Microbiology: Current Technology and Water Applications

June 15, 2010 Novel Antimicrobial Agents
Aberdeen, UK Further information
Society for General Microbiology/Society for Applied Microbiology/Society of Biology regional meeting on Novel Antimicrobial Agents, Robert Gordon University, Aberdeen, Scotland, United Kingdom. This regional meeting will be an opportunity to hear about developments in the field of antimicrobial agents primarily focussed on research taking place within Scotland.
Suggested reading: Microbiology Books

November 1 - 3, 2010 Bio-Processing and Application of Microbial Biotechnology in Agriculture
Cairo, Egypt Further information
1st International Conference of Bio-Processing and Application of Microbial Biotechnology in Agriculture
Suggested reading: Microbiology Books

Bacterial Spores

2010-05-17T14:17:51+01:00

Endospore-forming bacteria produce some of the most potent toxins known and are important pathogens in hospital-borne infections (Clostridium difficile) food contamination (Bacillus cereus, Clostridium botulinum), wound infestation (Clostridium perfringens, Clostridium tetani) and bioterrorism (Bacillus anthracis).

Bacilli and Clostridia spores form in response to unfavorable environmental conditions and can withstand extremes of heat, radiation, and chemical agents. The spore's durability is even more remarkable considering that dormant spores revert back to actively growing cells almost immediately after nutrients return to the environment. The intrinsic resistance and the ability to remain dormant for long periods make spores the perfect delivery vehicle for infectious diseases.

Further reading: The Ger Receptor Family from Sporulating Bacteria

The Ger Receptor Family

2010-05-17T14:12:07+01:00

Ger receptor activation is the first committed step in the germination process. Ger receptors are encoded, in general, as tricistronic operons containing three protein-coding genes, the A-, B-, and C-subunits. However, some Ger receptor subunits are encoded as orphan monocistronic genes and yet other ger receptor operons encode duplicated subunit genes.

The A-subunit protein of Ger receptors consist of five or six predicted membrane-spanning domains, as well as large N- and C-terminal hydrophilic domains. A-subunit proteins share significant homology to SpoVAF, a late-sporulation protein with no known function. Intriguingly, Ger receptors have been shown to interact with proteins from the spoVA operon. Whether these interactions are relevant to spore germination remains to be elucidated.

Further reading: The Ger Receptor Family from Sporulating Bacteria

Getting The Most Out of PCR

2010-05-13T15:22:59+01:00

We think you will be interested in an online seminar series entitled "Getting The Most Out of PCR", which is being broadcast by the popular life science blog, Bitesize Bio. Bitesize Bio is headed by Nick Oswald and Suzanne Kennedy, who co-edited our recent title "PCR Troubleshooting and Optimization".

The series lineup includes many of the authors from this book and kicks off on 18 May with a talk from LightCycler co-inventor, Carl Wittwer, entitled "Magic in Solution: An Introduction and Brief History of PCR". This will be a great learning experience with an opportunity to ask questions and learn from experts and pioneers in the PCR field. The full program is shown below.

Click here to book your place on these excellent events.

Magic in Solution: An Introduction and Brief History of PCR
Speaker: Carl Wittwer
18 May 2010 / 9am Pacific / 12pm Eastern / 5pm GMT / 6pm CET

Obtaining Maximum PCR Sensitivity and Specificity
Speaker: Cameron N. Gundry
25 May 2010 / 9am Pacific / 12pm Eastern / 5pm GMT / 6pm CET

Significance of Controls and Standard Curves in PCR
Speaker: Ian Kavanagh
01 June 2010 / 9am Pacific / 12pm Eastern / 5pm GMT / 6pm CET

The MBD2-based Enrichment Approach for Analyzing DNA methylation
Speaker: Chris Adams
08 June 2010 / 9am Pacific / 12pm Eastern / 5pm GMT / 6pm CET

The MIQE Guidelines Uncloaked
Speaker: Greg Shipley
15 June 2010 / 9am Pacific / 12pm Eastern / 5pm GMT / 6pm CET

High Resolution Melting Analysis - Beyond the SNP
Speaker: John Mackay
22 June 2010 / 9am Pacific / 12pm Eastern / 5pm GMT / 6pm CET

Pharmaceutical Microbiology

2010-05-06T12:36:42+01:00

June 15 - 16, 2010 Pharmaceutical Microbiology
Boston, MA, USA Further information
Best Practices for science and compliance in Pharmaceutical Microbiology. Microbiological contamination of products and processes continues to be a major concern to the industry and its regulators. The potential impact of such contamination can be catastrophic. This course, for non-biologists and microbiologists, is designed to provide you with the knowledge, confidence and decision making risk assessment skills to prevent this happening.
Suggested reading: Microbiology Books

Gastro-Intestinal Microbial Ecology

2010-05-06T12:33:40+01:00

November 9 - 11, 2010 International Scientific Conference on Gastro-Intestinal Microbial Ecology - GME2010
Kosice, Slovakia Further information
At GME2010 leading scientists will present and discuss current advances in the research of gut microbiota and gut microbial ecosystem. The scientific programme aims to advance the understanding of microbial diversity of the gastro-intestinal ecosystem by presenting new insights in its complex balance or imbalance, and discuss ways to modulate the gut microbiota to the benefit of the host by means of bioactive substances.
Suggested reading: Bifidobacteria: Genomics and Molecular Aspects

Neisseria Book Review

2010-05-06T08:41:55+01:00

I am pleased to provide the following excerpt from a book review of Neisseria: Molecular Mechanisms of Pathogenesis:

"written by outstanding and internationally highly recognized experts in the Neisseria research field ... The chapters are of the highest scientific quality including links to central primary publications on the different topics ... an excellent monography for the specialist" from Arzneimittelforschung/Drug Research (2010) 60: 226-227 read more ...

Neisseria: Molecular Mechanisms of Pathogenesis

Edited by: Caroline Genco and Lee Wetzler
ISBN: 978-1-904455-51-6
Publisher: Caister Academic Press
Publication Date: January 2010
Cover: Hardback

"a comprehensive update" (Society for Microbial Ecology and Disease)

Metagenomics Book Review

2010-05-06T08:35:42+01:00

I am pleased to provide the following excerpt from a book review of Metagenomics: Theory, Methods and Applications:

"the book is recommended for life science researchers and all students in biology and medicine wishing to learn more about this new and very interesting field" from Arzneimittelforschung/Drug Research (2010) 60: 226-227 read more ...

Metagenomics: Theory, Methods and Applications

Edited by: Diana Marco
ISBN: 978-1-904455-54-7
Publisher: Caister Academic Press
Publication Date: January 2010
Cover: Hardback

"an excellent resource for students, researchers, and scientists ... a valuable resource on the newly evolving biological field of metagenomics, making contributions to ecology, biodiversity, bioremediation, bioprospection of natural products, medicine, and other disciplines." (Doodys)

Vaccine Design Book

2010-05-05T14:00:47+01:00

A new book on Vaccine Design edited by Rino Rappuoli and Fabio Bagnoli has been announced today read more ...

Vaccine Design: Innovative Approaches and Novel Strategies Buy now!

Edited by: Rino Rappuoli and Fabio Bagnoli
ISBN: 978-1-904455-74-5
Publisher: Caister Academic Press
Publication Date: February 2011
Cover: Hardback

MicroRNAs as Regulators of Host-virus Interactions

2010-04-30T08:26:27+01:00

from Sassan Asgari and Christopher S. Sullivan in Insect Virology

MicroRNAs (miRNAs) are small non-coding RNA molecules that play a central role in the regulation of gene expression impacting many biological processes. These include development, cancer, apoptosis, immunity, and longevity. In addition, accumulating evidence suggest that miRNAs are likely to be involved in host-virus interactions by modulating expression levels of either defence genes or virus genes. Several groups of animal viruses, as well as insect viruses, encode miRNAs that are instrumental in virus biology, including replication, pathogenesis and latency. Of interest is the biogenesis of miRNAs, current approaches to the discovery of miRNAs, their mode of action and strategies for determining viral miRNA function.

Further reading: Insect Virology

Ecology of Baculoviruses

2010-04-30T08:22:56+01:00

from Jenny S. Cory in Insect Virology

Ecological studies involving insect viruses have centred on baculoviruses, partly because they are associated with population declines of some insect species, and also because they are highly pathogenic to insects, making them ideal candidates for pest control. Recent research has focussed on four main areas; (i) the influence of host condition on resistance to viral infection, (ii) the role and maintenance of baculovirus diversity, (iii) the prevalence of covert infections, and (iv) the elucidation of patterns of host resistance in field populations.

Tritrophic interactions, either via direct effects of plant secondary chemicals or through nutritionally mediated changes in host immunity, can have a significant impact on baculovirus efficacy. Variation within baculovirus populations appears to be ubiquitous, and mixed genotype infections apparently act to generate higher levels of pathogenicity. Covert infections are increasingly being shown to be common in field populations of Lepidoptera but their importance in generating overt baculovirus infections is still unclear. Field studies on forest insects indicate that host resistance varies with fluctuating host density and condition. Synthesis of the impacts of host condition on susceptibility, the role of genetic variability in infection, and of the relationship between overt and covert infection, will promote understanding of the ecological interactions between baculoviruses and natural host populations.

Further reading: Insect Virology

Insect viruses

2010-04-30T08:17:23+01:00

from Insect Virology

Viruses that are pathogenic to beneficial insects and other arthropods cause millions of dollars of damage to industries such as sericulture, apiculture and aquaculture every year (eg infecting honeybees and silk worms). On the other hand, viruses that are pathogenic to insect pests can be exploited as attractive biological control agents. Another fascinating feature of these viruses is that some, for example baculoviruses, have been commercially exploited for use as gene expression and delivery vectors in both insect and mammalian cells. All of these factors have led to an explosion in the amount of research into insect viruses in recent years generating impressive quantities of information on the molecular and cellular biology of these viruses.

Further reading: Insect Virology

Insect virology

2010-04-30T08:04:14+01:00

Sassan Asgari and Karyn N. Johnson (The University of Queensland, Australia) present a new book on Insect Virology
Virus groups covered include: Ascoviruses, Baculoviruses, Densoviruses, Entomopoxviruses, Hytrosaviruses, Iridoviruses, Nudiviruses, Polydnaviruses, Dicistroviruses, Iflaviruses, Nodaviruses, Tetraviruses and Cypoviruses. Several special topics chapters review current developments in insect virology including RNAi, insect antiviral responses, structural comparison of insect RNA viruses, and viral ecology read more ...

Insect Virology

Edited by: Sassan Asgari and Karyn N. Johnson
ISBN: 978-1-904455-71-4
Publisher: Caister Academic Press
Publication Date: September 2010
Cover: Hardback

Influenza book review

2010-04-29T16:28:11+01:00

I am pleased to provide the following excerpt from a book review of Influenza: Molecular Virology:

"This is a good quality, concise book on the basic nature of influenza viruses that comprehensively covers the current work on influenza." from Rebecca T. Horvat (University of Kansas Medical Center) writing in Doodys read more ...

Influenza: Molecular Virology

Edited by: Qinghua Wang and Yizhi Jane Tao
ISBN: 978-1-904455-57-8
Publisher: Caister Academic Press
Publication Date: February 2010
Cover: Hardback

Thiol-based sensory factors

2010-04-29T12:21:29+01:00

from Haike Antelmann and Peter Zuber in Sensory Mechanisms in Bacteria: Molecular Aspects of Signal Recognition

Bacteria regularly encounter Reactive Oxygen, Nitrogen and Electrophilic Species (ROS, RNS, RES) that are generated inside the cells by incomplete reduction of molecular oxygen, imbalanced metabolic processes or applied externally by toxic or antimicrobial compounds. The response to such reactive agents is mediated by redox-sensitive transcription factors that exploit the unique chemistry of cysteine thiol groups. Redox-sensitive regulatory proteins bear cysteine residues that can undergo post-translational modification, leading to either activation or inactivation of the transcription factors. This in turn results in responses that are aimed to detoxify the reactive species or alleviate the damage they cause. Different thiol-modifications are implicated in redox-sensing depending on the number of redox-active Cys residues and their reactivity, the oxidant to which they react, and the prevailing in vitro or in vivo conditions. Redox-sensitive proteins with more than one reactive Cys residue undergo in most cases reversible inter- and/or intramolecular disulfide linkages, which serve as sensing mechanisms for OxyR, the 2-Cys OhrR family, MexR, OspR, Spx, CprK and CrtJ. In contrast to these classical thiol-disulfide-switches, transcription factors with one redox-active Cys residue are reversibly regulated via initial sulphenic acid formation, S-thiolation with low molecular weight (LMW) thiols and sulfenamide formation with the backbone amide as shown for OxyR, the 1-Cys OhrR ortholog, MgrA and SarZ. However, the thiol group of the 1-Cys OhrR protein can also be irreversibly modified by overoxidation to sulfinic and sulfonic acids in response to strong oxidants. RES such as quinones were shown to modify the YodB repressor irreversibly by thiol-(S)-alkylation. In addition to redox-sensing transcription factors, LMW thiols and the thioredoxin/thioredoxin reductase system maintain the thiol-redox-balance of the cell upon exposure to reactive species. Here we review (1) enzymatic redox control mechanisms by thiol-disulfide reductases and (2) the current knowledge of bacterial redox-sensitive transcription factors that function without metal cofactors, including OxyR, OhrR, MexR, OspR, MgrA, SarZ, YodB, Spx, CprK and PspR/CrtJ. Each of these transcription factors senses unique signals including ROS, RNS, RES, antibiotic and haloorganic compounds, or the cellular oxygen level and light that are transduced via diverse redox-sensing mechanisms involving different reversible and irreversible thiol-modifications.

Further reading: Sensory Mechanisms in Bacteria: Molecular Aspects of Signal Recognition

Sensory Mechanisms in Bacteria

2010-04-29T12:17:06+01:00

from Sensory Mechanisms in Bacteria: Molecular Aspects of Signal Recognition

Bacteria have evolved extraordinary abilities to detect physical and chemical signals, both within their own cells and in the extracellular environment. The interaction of a signal with its receptor (usually a protein or RNA molecule) triggers a series of events that lead to reprogramming of cellular physiology, typically as a consequence of altered patterns of gene expression. In this way, the bacterial cell is able to mount appropriate and effective responses to changing physical and/or chemical environments. The versatility with which many bacteria adapt to environmental change underlies many important aspects of microbiology. For example, pathogens encounter multiple environments as they invade a host from the outside, and then progress through different sites within host tissues. There is growing evidence that pathogenic bacteria make use of physical and chemical cues to signal their presence in a suitable host, and need to adapt to the host environment in order to mount a successful infection. On the other hand, it should not be assumed that all signals to which bacteria must respond originate in the extracellular environment. For many species, even the cosseted life in a laboratory shake flask is 'stressful', in the sense that there is often a need to avoid or reverse the effects of harmful intermediates or by-products of metabolism. For example, all organisms that use dioxygen as a terminal electron acceptor have to deal with the reactive oxygen species that arise as adventitious by-products of aerobic metabolism. In bacteria, multiple protein receptors for oxygen radicals have been described, which control the expression of genes encoding enzymes that detoxify oxygen radicals or repair the damage that they cause.

Further reading: Sensory Mechanisms in Bacteria: Molecular Aspects of Signal Recognition

Signal Recognition Book

2010-04-29T12:07:55+01:00

Stephen Spiro and Ray Dixon (Texas, USA and Norwich,UK; respectively) present a new publication Sensory Mechanisms in Bacteria: Molecular Aspects of Signal Recognition
This book reviews a selection of important model systems, providing a timely snapshot of the current state of research in the field. The book opens with an introductory chapter that reviews the diversity of signal recognition mechanisms, illustrating the breadth of the field. Subsequent chapters include descriptions of the sensing of ligands (alpha-ketoglutarate, adenylate energy charge, glutamine and xenobiotic compounds), chemoreceptors, iron-sulfur cluster-based sensors, metal-dependent and metal-responsive sensors, thiol-based sensors, and PDZ domains as sensors of other proteins read more ....

Sensory Mechanisms in Bacteria: Molecular Aspects of Signal Recognition

Edited by: Stephen Spiro and Ray Dixon
ISBN: 978-1-904455-69-1
Publisher: Caister Academic Press
Publication Date: September 2010
Cover: Hardback

Probiotic properties of bifidobacteria

2010-04-28T14:31:00+01:00

from Maddalena Rossi and Alberto Amaretti in Bifidobacteria: Genomics and Molecular Aspects

Bifidobacteria are major components of the indigenous bacterial population present in the human gut and are arguably most relevant to the health-promoting properties that have been attributed to elements of this microbiota. They exert a range of beneficial health effects, including the regulation of intestinal microbial homeostasis, the inhibition of pathogens and harmful bacteria that colonize and/or infect the gut mucosa, the modulation of local and systemic immune responses, the repression of procarcinogenic enzymatic activities within the microbiota, the production of vitamins, and the bioconversion of a number of dietary compounds into bioactive molecules. Health-promoting properties of members of the genus Bifidobacterium have been reported but research is still necessary for an in depth understanding of the probiotic function. In fact, although experimental evidence of the probiotic effectiveness of bifidobacteria has a long history, little information is available on the molecular mechanisms underlying the health-promoting claims, especially on such complex phenomena as anticarcinogenic and anti-inflammatory effects.

Further reading:

Metabolism of bifidobacteria

2010-04-28T14:28:23+01:00

from David A. Sela, Neil P. J Price and David A. Mills in Bifidobacteria: Genomics and Molecular Aspects

The genus Bifidobacterium possesses a unique fructose-6-phosphate phosphoketolase pathway employed to ferment carbohydrates. Much metabolic research on bifidobacteria has focused on oligosaccharide metabolism as these carbohydrate polymers are available in their otherwise nutrient-limited habitats. Interestingly, infant-associated bifidobacterial phylotypes appear to have evolved the ability to ferment milk oligosaccharides, whereas adult-associated species utilize plant oligosaccharides, consistent with what they encounter in their respective environments. As breast-fed infants often harbor bifidobacteria dominated gut consortia, there have been numerous applications to mimic the bifidogenic properties of milk oligosaccharides. These are broadly classified as plant-derived fructo-oligosaccharides or dairy-derived galacto-oligosaccharides, which are differentially metabolized and distinct from milk oligosaccharide catabolism.

Further reading:

Genomics of Bifidobacteria

2010-04-28T14:25:33+01:00

from Marco Ventura, Francesca Turroni, Francesca Bottacini and Douwe van Sinderen in Bifidobacteria: Genomics and Molecular Aspects

During recent years microbiological research has been fundamentally changed by the ever increasing number of publicly available bacterial whole-genome sequences. This sequence information has largely affected our understanding of the metabolic capabilities, genetics and phylogeny of bacteria. Bifidobacteria constitute one of the key microbial groups of the human intestinal microbiota, due to their perceived positive contribution to maintain a balanced gut homeostasis. In recent years bifidobacteria have drawn much scientific attention because of their use as live bacteria in numerous food preparations with several health-related claims. For this reason these bifidobacteria represent a developing area of scientific interest with respect to genomics, molecular biology, genetics and physiology. Recent genome sequencing of different bifidobacterial species has provided the complete genetic make-up of these bacteria.

Further reading:

Bifidobacteria

2010-04-28T14:21:08+01:00

from Bifidobacteria: Genomics and Molecular Aspects

Bifidobacteria are Gram-positive anaerobic bacteria, found naturally in the gut of humans and other mammals. They are widely used as probiotic organisms in a vast array of formulations for the prevention, alleviation and treatment of many intestinal disorders. However bifidobacteria are fastidious microorganisms and difficult to study in the laboratory, so until recently, understanding of their genetics lagged behind that of other high GC content Gram-positive bacteria. The application of modern whole genome approaches to bifidobacteria research has changed all of this, permitting the accumulation of an impressive amount of data, something that could not have been foreseen a few years ago.

Among the myriad of bacterial species that inhabit the human gut and the gut of many animals, bifidobacteria are almost certainly the microbial group that has the greatest effect on the health of the host. In most people, bifidobacteria are present in high numbers (10⁸-10⁹ cells/g of intestinal content) throughout their lives, although each individual permanently harbours only several species or specific biotypes. Apart from lactobacilli, bifidobacteria is the only intestinal microbial group that is generally recognized to possess such positive characteristics through its capacity to produce short chain fatty acids, vitamins, bacteriocins and antibiotic-like substances, and of exerting immunomodulating and immunostimulating activities. Moreover, the bifidobacterial species so far identified lack enzyme urease, azo- and nitro-reductase, beta-glucuronidase and alpha-dehydrolase that exert enzymatic and metabolic effects that are perceived to be toxic to the host. Consequently, bifidobacteria can be considered as valuable probiotics and today they are not only used in the food industry to relieve and treat many intestinal disorders, but they are increasingly attracting the scientific interest of clinicians and researchers.

Further reading:

Bifidobacteria book

2010-04-28T14:12:10+01:00

Baltasar Mayo and Douwe van Sinderen (Asturias, Spain and Cork, Ireland; respectively) present a new publication Bifidobacteria: Genomics and Molecular Aspects
This book brings together the expertise and enthusiasm of leading bifidobacteria experts from around the world to provide a state-of-the art overview of the molecular biology and genomics of this important microbial genus. Topics include: ecology, genomics, comparative genomics, metabolism, acid and bile resistance, stress response, probiotic properties, antimicrobial activity, interaction with the intestinal mucosa, safety assessment of bifidobacteria, synthesis and utilization of exopolysaccharides and prebiotics, antibiotic resistance/susceptibility profiles, viability and stability in commercial preparations, mobile genetic elements, cloning vectors and genetic manipulation of bifidobacteria read more ...

Bifidobacteria: Genomics and Molecular Aspects

Edited by: Baltasar Mayo and Douwe van Sinderen
ISBN: 978-1-904455-68-4
Publisher: Caister Academic Press
Publication Date: August 2010
Cover: Hardback

Detection of Viable Organisms Using Molecular Techniques

2010-04-27T14:44:59+01:00

from Paul A. Rochelle, Anne K. Camper, Andreas Nocker and Mark Burr in Environmental Microbiology: Current Technology and Water Applications

The ultimate measure of microbial viability and biological activity is growth in some form of culture system. Unfortunately, due to many limitations, growth is usually not the most sensitive or rapid detection method. Many molecular-based tools are available for assessing viability and functional gene expression, and have applications for specific microbes in environmental samples. Methods include fluorescent nucleic acid binding dyes, enzymatic conversion of substrates to fluorescent compounds (often in conjunction with nucleic acid-based methods), various techniques based on amplification and detection of nucleic acids, nucleic acid amplification linked to biosensors and microarray detection platforms, detection and characterization of proteins, and molecular detection coupled with culturing.

Further reading:

Identity of Single Microbial Cells

2010-04-27T14:43:11+01:00

from Daniel S. Read and Andrew S. Whiteley in Environmental Microbiology: Current Technology and Water Applications

Linking both identity and function within microbial communities has long been seen as essential for understanding the role that bacteria play in the environment. Techniques based on the study of single microbial cells offer a unique approach that provides information about heterogeneity within populations, and the role of spatial organization within the environment. Various single-cell techniques are currently in use for the study of microbial ecology, an important one being Raman spectroscopy. This technique can be used for studying different features of microbial systems. Raman spectroscopy can be used in combination with Fluorescence in situ Hybridization (FISH) and Stable Isotope Probing (SIP), which together can be utilized to gain an insight into the identity and function of single bacterial cells in situ.

Further reading:

Amoebae as a Tool

2010-04-27T14:41:36+01:00

from Julia Lienard and Gilbert Greub in Environmental Microbiology: Current Technology and Water Applications

Obligate intracellular microorganisms are unculturable by classic axenic culture methods. As a result they have largely been overlooked, despite many being significant human and animal pathogens. Resistance of amoeba-resisting microorganisms (ARM) to amoebal destruction may predict ability to also resist mammalian macrophages, which are somehow similar to amoebae and represent one of the first cellular immune defenses in mammals. Thus, general approaches have been described for the growth of strict intracellular microorganisms, using amoebae as hosts in a cell culture system. Such an approach has been shown to be advantageous, since amoebal co-culture will selectively grow microorganisms that resist these professional phagocytes. An alternative approach for the isolation of novel ARM is also available, which requires the isolation of new amoebal strains by amoebal enrichment on a suitable prey (such as Escherichia coli), and then to search for intra-amoebal microorganisms within the isolated amoebae. Once new potentially pathogenic ARM has been isolated, one should then further assess the potential infectivity of these intracellular microorganisms. The application of macrophages, as an in vitro model to test microbial virulence is also possible.

Further reading:

Detection of Pathogens in Water Using Microarrays

2010-04-27T14:40:12+01:00

from Timothy M. Straub in Environmental Microbiology: Current Technology and Water Applications

For waterborne pathogen monitoring, regulatory agencies have traditionally focused on developing a single method for an existing or emerging pathogen in water supplies. However, the ability to use a single method to determine all potential pathogens or indicators in a water supply would be particularly advantageous. Such an approach has three major hurdles: 1) sensitive detection of highly dilute pathogens in a water supply, 2) specific detection of pathogens from non-pathogenic near-neighbors, and 3) multiplexed strategies that preserve the sensitivity and specificity of the assay.

Further reading:

Low Cost Screening of Multiple Waterborne Pathogens

2010-04-27T14:38:40+01:00

from Seyrig et al in Environmental Microbiology: Current Technology and Water Applications

A vast array of low cost, simple, rugged, and rapid molecular approaches are emerging for the detection of indicators and pathogens, along with the collection of relevant genotypic information. Loop-mediated isothermal amplification (LAMP) is a relatively new DNA amplification technique, which due to its simplicity, ruggedness, and low cost could provide major advantages to the water industry. In LAMP, the target sequence is amplified at a constant temperature using either two or three sets of primers and a polymerase with high strand displacement activity. Due to the specific nature of the action of these primers, the amount of DNA produced in LAMP is considerably higher than PCR based amplification. The corresponding release of pyrophosphate results in visible turbidity due to precipitation, which allows easy visualization by the naked eye, especially for larger reaction volumes or via simple detection approaches for smaller volumes. The reaction can be followed in real-time either by measuring the turbidity or the signals from DNA produced via fluorescent dyes that intercalate or directly label the DNA, and in turn can be correlated to the number of copies initially present. Hence, LAMP can also be quantitative. While LAMP is already the method of choice in organizations engaged in combating infectious diseases such as tuberculosis, malaria, and sleeping sickness in developing regions, it has yet to be extensively validated for commonly known waterborne pathogens.

Further reading:

Biosensors for the Detection of Waterborne Pathogens

2010-04-27T14:37:27+01:00

from Sen Xu and Raj Mutharasan in Environmental Microbiology: Current Technology and Water Applications

The detection of waterborne pathogens and toxins by biosensor-based methods are becoming increasingly important. Optical, electrochemical and electromechanical sensors are available and surface chemistries are being used for immobilizing biorecognition molecules on sensor surfaces. Topics that are important include representative sensor responses, limit of detections (LOD) and time to results (TTR).

Further reading:

Detection of Microbes in Water

2010-04-27T14:35:16+01:00

from Keya Sen in Environmental Microbiology: Current Technology and Water Applications

Molecular techniques based on genomics, proteomics and transcriptomics are rapidly growing as complete microbial genome sequences are becoming available, and advances are made in sequencing technology, analytical biochemistry, microfluidics and data analysis. While the clinical and food industries are increasingly adapting these techniques, there appear to be major challenges in detecting health-related microbes in source and treated drinking waters. This is due in part to the low density of pathogens in water, necessitating significant processing of large volume samples. From the vast panorama of available molecular techniques, some are finding a place in the water industry: Quantitative PCR, protein detection and immunological approaches, loop-mediated isothermal amplification (LAMP), microarrays.

Further reading:

Biofilms

2010-04-27T11:25:47+01:00

from "Nanozymes for Biofilm Removal" Melanie Richards and Thomas Eugene Cloete in Nanotechnology in Water Treatment Applications
Sessile communities of bacteria encased in extracellular polymeric substances (EPS) are known as biofilms and causes serious problems in various areas, amongst other, the medical industry, industrial water settings, paper industry and food processing industry. Although various methods of biofilm control exist, these methods are not without limitations and often fail to remove biofilms from surfaces. Biofilms often show reduced susceptibility to antimicrobials or chemicals and chemical by-products may be toxic to the environment, whereas mechanical methods may be labour intensive and expensive due to down-time required to clean the system.

Further reading:

Risk assessment of nanoparticles and nanomaterials

2010-04-27T11:21:49+01:00

from Michele de Kwaadsteniet and Thomas Eugene Cloete in Nanotechnology in Water Treatment Applications
The risk assessment of nanoparticles and nanomaterials is of key importance for the continous development in the already striving new field of nanotechnology. Humans are increasingly being exposed to nanoparticles and nanomaterials, placing stress on the development and validation of reproducible toxicity tests. Tests currently used include genotoxicity and cytotoxicity tests, and in vivo toxicity models. The unique characteristics of nanoparticles and nanomaterials are responsible for their toxicity and interaction with biological macromolecules within the human body. This may lead to the development of diseases and clinical disorders. A loss in cell viability and structure can also occur in exposed tissues as well as inflammation and granuloma formation. The future of nanotechnology depends on the responsible assessment of nanoparticles and nanomaterials.

Further reading: Nanotechnology in Water Treatment Applications

Detection of Microbial Pathogens

2010-04-27T11:15:44+01:00

from Jacques Theron, Thomas Eugene Cloete and Michele de Kwaadsteniet in Nanotechnology in Water Treatment Applications
Detection of pathogens often involves time-consuming culture methods. Newer enzymatic, immunological and genetic methods are being developed to replace and/or support classical approaches to microbial detection. Innovations in nanotechnology and nanosciences are having a significant impact in biodiagnostics, where a number of nanoparticle-based assays and nanodevices have been introduced for biomolecular detection.
Waterborne disease is still a major cause of death in many parts of the world, particularly in young children, the elderly, or those with compromised immune systems. As the epidemiology of waterborne diseases is changing, there is a growing global public health concern about new and reemerging infectious diseases that are occurring through a complex interaction of social, economic, evolutionary, and ecological factors. An important challenge is therefore the rapid, specific and sensitive detection of waterborne pathogens.
Further reading: Nanotechnology in Water Treatment Applications

Nanotechnology and Water Microbiology

2010-04-27T11:12:41+01:00

Nanotechnology is the engineering and art of manipulating matter at the nanoscale (1-100 nm) level. Nanotechnology offers the potential of novel nanomaterials for the treatment of surface water, groundwater and wastewater contaminated by toxic metal ions, organic and inorganic solutes and microorganisms. At the present time many nanomaterials are under active research and development.

Further reading: Nanotechnology in Water Treatment Applications

Biofilm Removal using Nanozymes

2010-04-27T09:22:22+01:00

from Melanie Richards and Thomas Eugene Cloete in Nanotechnology in Water Treatment Applications

Recently there has been a great interest in the enzymatic degradation of biofilms. Enzymes are highly selective and disrupt the structural stability of the biofilm EPS matrix. Various studies have focused on the enzymatic degradation of polysaccharides and proteins for biofilm detachment since these are the two dominant components of the EPS. Due to the structural role of proteins and polysaccharides in the EPS matrix, a combination of various proteases and polysaccharases may be successful in biofilm removal.

The biodegradability and low toxicity of enzymes also make them attractive biofilm control agents. Regardless of all the advantages associated with enzymes, they also suffer from various drawbacks given that they are relatively expensive, show insufficient stability or activity under certain conditions, and cannot be reused. Various approaches are being used to increase the stability of enzymes, including enzyme modification, enzyme immobilization, protein engineering and medium engineering. Although these conventional methods have been used frequently to improve the stability of enzymes, various new techniques, such as self-immobilization of enzymes, the immobilization of enzymes on nano-scale structures and the production of single-enzyme nanoparticles, have been developed.

Self-immobilization of enzymes entails the cross-linking of enzyme molecules with each other and yields final preparations consisting of essentially pure proteins and high concentrations of enzyme per unit volume. The activity, stability and efficiency of immobilized enzymes can be improved by reducing the size of the enzyme-carrier. Nano-scale carrier materials allow for high enzyme loading per unit mass, catalytic recycling and a reduced loss of enzyme activity. Furthermore, enzymes can be stabilized by producing single-enzyme nanoparticles consisting of single-enzyme molecules surrounded by a porous organic-inorganic network of less than a few nanometers thick.

All these new technologies of enzyme stabilization make enzymes even more attractive alternatives to other biofilm removal and control agents.

Further reading:

EBV

2010-04-23T12:17:58+01:00

A new publication on EBV: Epstein-Barr Virus: Latency and Transformation was published recently. In this book, expert EBV virologists comprehensively review this important subject from a genetic, biochemical, immunological, and cell biological perspective. Topics include: latent infections, EBV leader protein, EBNA-1 in viral DNA replication and persistence, EBNA-2 in transcription activation of viral and cellular genes, the nuclear antigen family 3 in regulation of cellular processes, molecular profiles of EBV latently infected cells, latent membrane protein 1 oncoprotein, regulation of latency by LMP2A, role of noncoding RNAs in EBV-induced cell growth and transformation and the regulation of EBV latency by viral lytic proteins. This book is essential reading for all EBV virologists as well as clinical and basic scientists working on oncogenic viruses read more ...

Epstein-Barr Virus: Latency and Transformation

Edited by: Erle S. Robertson
ISBN: 978-1-904455-62-2
Publisher: Caister Academic Press
Publication Date: April 2010
Cover: Hardback
read more ...

Molecular Phylogeny of Microorganisms

2010-04-23T11:19:48+01:00

Aharon Oren and R. Thane Papke of The Hebrew University of Jerusalem, Israel and the University of Connecticut, USA (respectively) present a new publication on microbial phylogeny: Molecular Phylogeny of Microorganisms. Leading scientists from around the world explore current concepts in molecular phylogeny and their application with respect to microorganisms. The authors describe the different approaches applied today to elucidate the molecular phylogeny of prokaryotes (and eukaryotic protists) and review current phylogenetic methods, techniques and software tools. Topics covered include: a historical overview, computational tools, multilocus sequence analysis, 16S rRNA phylogenetic trees, rooting of the universal tree of life, applications of conserved indels, lateral gene transfer, endosymbiosis and the evolution of plastids.

This book is an ideal introduction to molecular phylogeny for all microbiologists and is an essential review of current concepts for experts in the field. A recommended text for all microbiology laboratories read more ...

Molecular Phylogeny of Microorganisms

Edited by: Aharon Oren and R. Thane Papke
ISBN: 978-1-904455-67-7
Publisher: Caister Academic Press
Publication Date: July 2010
Cover: Hardback
read more ...

Population genetics book

2010-04-20T16:46:13+01:00

The new book on Microbial Population Genetics edited by Jianping Xu (McMaster University, Hamilton, Canada) has been published and is available for immediate dispatch read more ...

Anaerobic Parasitic Protozoa

2010-04-15T15:04:14+01:00

The new book on Anaerobic Parasitic Protozoa edited by C. Graham Clark, Patricia J. Johnson and Rodney D. Adam was published this week read more ...

Anaerobic Parasitic Protozoa: Genomics and Molecular Biology

Edited by: C. Graham Clark, Patricia J. Johnson and Rodney D. Adam
Published: 2010 ISBN: 978-1-904455-61-5
Price: GB £159 or US $310
In this book internationally acclaimed researchers critically review the most important aspects of research on anaerobic parasitic protozoa, providing the first coherent picture of their genomics and molecular biology since the publication of the genomes. Chapters are written from a molecular and genomic perspective and contain speculative models upon which future research efforts can be based. read more ...

ABC Transporters book review

2010-04-15T10:32:51+01:00

Excerpt from a book review that was published recently:

ABC Transporters in Microorganisms
ISBN: 978-1-904455-49-3
"very capably edited ... a comprehensive collection of color illustrations and relevant tables ... thorough and easy-to-read series of informative chapters written by experts ... The detail and insight provided as well as thorough referencing in each chapter suggest that this collection will be an excellent addition to most libraries in medical schools and research laboratories" from Joni Tillotson and Glenn S. Tillotson (Immaculata University, Malvern and ViroPharma Incorporated, Exton, PA, USA) writing in Expert Rev. Anti Infect. Ther. 8(4), 375-377 (2010) read more ...

Aspergillus book review

2010-04-15T10:31:00+01:00

Excerpt from a book review that was published recently:

Aspergillus: Molecular Biology and Genomics
ISBN: 978-1-904455-53-0
"a thorough review of recent research in the genetics of Aspergillus ... It has information on Aspergillus species that is difficult to find in other sources." from Rebecca T. Horvat (University of Kansas Medical Center) writing in Doodys read more ...

Retroviruses book review

2010-04-15T10:28:21+01:00

Excerpt from a book review that was published recently:

Retroviruses: Molecular Biology, Genomics and Pathogenesis
ISBN: 978-1-904455-55-4
"impressive work ... a substantial resource to the field ... thorough state of research coverage by leading specialists ... essential reading for veterinary scientists, clinicians, virologists, and graduate students in the field." from SciTech Book News (March 2010) read more ...

Anaerobic Parasitic Protozoa

2010-03-30T16:24:34+01:00

C. Graham Clark, Patricia J. Johnson and Rodney D. Adam present a new publication Anaerobic Parasitic Protozoa: Genomics and Molecular Biology. Internationally acclaimed researchers critically review the most important aspects of research on anaerobic parasitic protozoa, providing the first coherent picture of their genomics and molecular biology since the publication of the genomes. Chapters are written from a molecular and genomic perspective and contain speculative models upon which future research efforts can be based. Topics include: the genomes of Entamoeba histolytica, Trichomonas vaginalis, Giardia and other diplomonads; the cytoskeletons of Entamoeba histolytica, Giardia lamblia and Trichomonas vaginalis; genomic analyses and manipulation of gene expression in Entamoeba histolytica; nuclear and chromosomal structure and replication in Giardia; and the mitochondrion-like organelles of Blastocystis read more ....

Metagenomics book review

2010-03-30T15:24:11+01:00

The following excerpt is from a recent book review of Metagenomics: Theory, Methods and Applications:

"an excellent resource for students, researchers, and scientists ... a valuable resource on the newly evolving biological field of metagenomics, making contributions to ecology, biodiversity, bioremediation, bioprospection of natural products, medicine, and other disciplines." from Omer Iqbal (Loyola University Medical Center) writing in Doodys read more ...

Metagenomics: Theory, Methods and Applications

Edited by: Diana Marco
ISBN: 978-1-904455-54-7
Publisher: Caister Academic Press
Publication Date: January 2010
Cover: Hardback
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Antibiotic Resistance in Neisseria

2010-03-30T08:20:24+01:00

from William M. Shafer, Jason P. Folster and Robert A. Nicholas in Neisseria: Molecular Mechanisms of Pathogenesis
Diseases caused by the pathogenic Neisseria (N. gonorrhoeae and N. meningitidis) have been successfully treated with antibiotics for the past 70 years. However, a disturbing trend worldwide is the increasing prevalence of strains with resistance to inexpensive and widely available antibiotics (e.g., penicillin, tetracycline and ciprofloxacin) and the emergence of strains exhibiting decreased susceptibility to effective antibiotics that are expensive and not always available (e.g. third-generation cephalosporins and the newer macrolides).

A recent publication reports that the global problem of antibiotic resistance will continue (and worsen) in the foreseeable future. By understanding the mechanisms of antibiotic resistance in gonococci and meningococci, resistance to antibiotics currently in clinical practice can be anticipated and the design of novel antimicrobials to circumvent this problem can be undertaken more rationally. The authors review the genetic and physiologic basis by which the pathogenic Neisseria developed resistance to historically important antibiotics and how resistance to newer antibiotics is emerging.

Neisseria: Molecular Mechanisms of Pathogenesis

Salmonella book

2010-03-29T17:20:28+01:00

A new book entitled Salmonella: From Genome to Function has just been announced:

Salmonella: From Genome to Function

Edited by: Steffen Porwollik
ISBN: 978-1-904455-73-8
Publisher: Caister Academic Press
Publication Date: January 2011
Cover: Hardback
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More information ...

PCR book

2010-03-29T17:11:05+01:00

New PCR book announced:
The book describes and discusses strategies for preparing effective controls and standards for PCR, when they should be employed and how to interpret the information they provide. The significance of optimization for efficiency, precision and sensitivity of PCR methodology and essential guidance on how to troubleshoot inefficient reactions. Design and optimization techniques, the use of appropriate controls, the significance of standard curves and the principles and strategies required for effective troubleshooting. The importance of sample preparation and quality, primer design, controlling inhibitors, avoiding amplicon and environmental contamination, optimizing reagent quality and concentration, and modifying the thermal cycling protocol for optimal sensitivity and specificity read more.

PCR Troubleshooting and Optimization: The Essential Guide

Edited by: Suzanne Kennedy and Nick Oswald
ISBN: 978-1-904455-72-1
Publisher: Caister Academic Press
Publication Date: January 2011
Cover: Hardback
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H pylori book review

2010-03-25T15:24:20+00:00

Excerpt from a recent book review of Helicobacter pylori: Molecular Genetics and Cellular Biology.

"contains 12 chapters that update key areas of basic research ... this book should be useful for researchers in the H. pylori field as well as anyone working in closely related organisms." from D. Scott Merrell (Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, Maryland, USA) writing in The Quarterly Review of Biology (2010) 85: 110. read more ...

Dengue Book Review

2010-03-25T15:21:35+00:00

Excerpt from a recent book review of Frontiers in Dengue Virus Research.

"a reference for scientists studying arboviruses and infections. Chapters are well written with very little overlap. It would be a good investment for laboratories interested in arboviral diseases" from Doodys (2010) read more ...

Retroviruses Book Review

2010-03-25T12:26:36+00:00

The following excerpt is from a recent book review of Retroviruses: Molecular Biology, Genomics and Pathogenesis.

"excellent chapters on non-primate mammalian retroviruses, simian retroviruses, fish retroviruses, use of retoviral vectors, and cellular factors that restrict retroviral infection. All the chapters are beautifully illustrated and written by some of the most respected authorities in the field. I highly recommend K&B's "Retroviruses" book to both students and expert colleagues."

from Kuan-Teh Jeang (Head, Molecular Virology Section LMM, NIAID, USA) writing in Retrovirology read more ...

Retroviruses: Molecular Biology, Genomics and Pathogenesis

Edited by: Reinhard Kurth and Norbert Bannert
ISBN: 978-1-904455-55-4
Publisher: Caister Academic Press
Publication Date: January 2010
Cover: Hardback
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Top 50 Blogs

2010-03-17T11:32:20+00:00

We are proud to note that the Microbiology Blog has been listed in the Top 50 Biology Research Blogs.

Borrelia Book

2010-03-15T12:40:19+00:00

The following book on the spirochete Borrelia has just been published (March 15, 2010).

Borrelia: Molecular Biology, Host Interaction and Pathogenesis

Edited by: D. Scott Samuels and Justin D. Radolf
ISBN: 978-1-904455-58-5
Publisher: Caister Academic Press
Publication Date: March 2010
Cover: Hardback
read more ...

Conference: Biosensors

2010-03-05T15:30:38+00:00

May 26 - 28, 2010 20th Anniversary World Congress on Biosensors
Glasgow, UK Further information
Biosensors 2010. Top plenary speakers, parallel symposia outlining the latest research in biosensors and related technologies supported by extensive poster sessions and an exhibition.
Suggested reading: Molecular Biology Books

Book Review: RNAi

2010-03-05T14:43:27+00:00

"The use of RNA interference to control gene expression is emerging as an exciting new technology. The potential of this mechanism depends on the ability to find a competent way to deliver the RNA. This compact book reviews all of these issues in a comprehensive manner." from Doodys (2010)

Further reading: RNA Interference and Viruses: Current Innovations and Future Trends

New Book on Water and Environmental Microbiology

2010-03-03T17:09:47+00:00