"The book ... introduces the reader to what is known thus far and to the current challenges in the taxonomy, genomics and proteomics, diagnosis and epidemiology, vaccine development, virulence mechanisms, and life cycle posed by these enigmatic bacteria. The authors of the 13 chapters are experts in the field ... (the book)can be recommended to microbiologists, immunologists, veterinarians, and clinicians with an interest in microbial pathogenesis, host-bacterium interactions, and microbial diagnosis." from Mercedes Berlanga (University of Barcelona, Spain) writing in International Microbiology (2011) 14: 235-236 read more ...

Brucella: Molecular Microbiology and Genomics Edited by: Ignacio López-Goñi and David O'Callaghan ISBN: 978-1-904455-93-6 Publisher: Caister Academic Press Publication Date: February 2012 Cover: hardback "recommended to microbiologists, immunologists, veterinarians, and clinicians" Int. Micro.

"a must-have for anyone interested in Brucella spp and brucellosis ... a comprehensive and detailed review of the most recent advances regarding Brucella ... This well-referenced book will be a welcome addition to the libraries of researchers, laboratory workers, molecular biologists, microbiologists, and veterinarians ... For those looking for a single, detailed reference on Brucella organisms, purchasing this book will be money well spent." from Angela Arenas writing in J. Vet. Med. Assoc. (2012) 240: 686. read more ...

Brucella: Molecular Microbiology and Genomics Edited by: Ignacio López-Goñi and David O'Callaghan ISBN: 978-1-904455-93-6 Publisher: Caister Academic Press Publication Date: February 2012 Cover: hardback "a must-have for anyone interested in Brucella" (J. Vet. Med. Assoc.)

from R. Martin Roop II, Eric Anderson, Jenifer Ojeda, David Martinson, Evan Menscher and Daniel W. Martin writing in Brucella: Molecular Microbiology and Genomics:

Like most other living organisms, Brucella strains require a variety of metals as micronutrients to serve as co-factors and structural components of enzymes and other cellular proteins. Genetic studies have shown that the efficient transport of iron, magnesium, manganese, and zinc are essential for the virulence of Brucella strains in experimental and natural hosts. This chapter will review what is presently known about the metal acquisition and homeostasis systems in Brucella strains.

Further reading: Brucella: Molecular Microbiology and Genomics

from Thomas A. Ficht and Allison C. Rice-Ficht writing in Brucella: Molecular Microbiology and Genomics:

Development of improved Brucella vaccines has focused on the identification of the genes that support intracellular survival and those encoding antigens capable of stimulating immune protection. Evaluation of live, attenuated vaccines and subunit vaccines expressed using numerous vector-based systems has provided two general results: i) vaccines providing little protection with elevated safety, and ii) vaccines exhibiting excellent protection that are of questionable safety. In order to address the limitations associated with Brucella vaccinology a fresh look at the interactions between host and pathogen may provide renewed insight. This chapter attempts to reconcile the varied results reported in the literature related to the host response to the invading pathogen and the mechanisms used by the organism to avoid both innate and adaptive immune responses. By reviewing and summarizing the current literature we expect to reveal focal points for new investigations and that inconsistencies limiting such development may be identified and dealt with constructively.

Further reading: Brucella: Molecular Microbiology and Genomics

from Christian Baron, Jean-Yves Winum and Stephan Köhler writing in Brucella: Molecular Microbiology and Genomics:

Novel strategies for the treatment of bacterial infectious diseases are urgently needed. In this chapter we will discuss two complementary approaches aimed at targeting Brucella species during the intracellular growth phase: depriving them of essential amino acid biosynthetic enzymes and disarmament by inhibiting type IV secretion system function that is essential for virulence. Small molecules targeting these functions that are essential exclusively during intracellular growth could serve as leads for the development of novel anti-infective and anti-virulence drugs, respectively. Since such drugs would not kill Brucella during extracellular growth, it is anticipated that the selection pressure for resistant mutants would be reduced. In addition, such specific molecules would not disrupt the human microbiome and thereby avoid side effects of conventional antibiotic treatments. Following similar approaches, anti-infective and anti-virulence drugs could be developed to treat infections caused by a wide variety of bacterial pathogens.

Further reading: Brucella: Molecular Microbiology and Genomics

from Adrian M. Whatmore and Krishna K. Gopaul writing in Brucella: Molecular Microbiology and Genomics:

For many years, the diagnosis of brucellosis depended on tried and tested cultural and serological approaches. However, whilst these techniques have been instrumental in successful control and eradication schemes such as the one undertaken in Great Britain, these methods are not ideal. As a highly infectious zoonotic pathogen culture of Brucella is hazardous whilst serological tests targeting lipopolysaccharide can be compromised by non-specific cross-reactions. With rapid advances in molecular biology, and driven by the need for improved diagnostic and epidemiological approaches, novel techniques based on the genetic component of the pathogen have become more popular in recent years. In this chapter we will discuss the current status of development and implementation of such techniques applied to Brucella whilst also looking forward at potential avenues for further molecular advancement.

Further reading: Brucella: Molecular Microbiology and Genomics

from Renee M. Tsolis and David O'Callaghan writing in Brucella: Molecular Microbiology and Genomics:

The type IV secretion system (T4SS) encoded by the virB operon is a key pathogenicity determinant that is highly conserved among Brucella species, and is one of the few "classical" virulence factors identified to date. Since its first description in 1999, work on the VirB T4SS has focused on its role in intracellular survival and persistence, its architecture and assembly in the cell envelope, on the signals that induce its expression and function within the infected host cell, on identification of T4SS substrates, and on its effect on the host response to infection. In this chapter, we review the advances in our understanding of structure/function relationships of the T4SS, and of its function in infection by Brucella species.

Further reading: Brucella: Molecular Microbiology and Genomics

from Juan M. García-Lobo, María C. Rodríguez, Asunción Seoane, Félix J. Sangari, and Ignacio López-Goñi writing in Brucella: Molecular Microbiology and Genomics:

In this chapter we will analyze the results available on the characterization of the Brucella transcriptome. After a summary of earlier work on transcription, two technical approaches will be mainly described, on one side the use microarrays, specially that derived from the Brucella ORFeome that allows hybridization with mRNA derived cDNA to determine the relative abundance of transcripts from each B. melitensis ORF. On the other, RNAseq, consisting in the massive sequencing of cDNA libraries derived from mRNA obtained from B. abortus grown in culture medium. Sequencing with the Illumina Genome-Analyzer II platform, produced 3 millions of 35 nt long reads that annealed with single copy coding regions of the genome. This allowed a good coverage for every CDS and produced a new dataset on the transcription of Brucella. We obtained a good correlation for the set of highly expressed genes from the microarrays and confirmed the observations obtained on the asymmetry between chromosome transcription. Preliminary conclusions on intracellular transcription have been drawn from RT-PCR on selected candidate genes and from microarray datasets obtained from virulence related conditions.The RNAseq derived data allowed more versatile data mining giving some new details on transcription from pseudogenes or intergenic regions.

Further reading: Brucella: Molecular Microbiology and Genomics

from Ignacio López-Goñi writing in Brucella: Molecular Microbiology and Genomics:

Recent results from proteomic and transcriptomic analyses show that the two component system BvrR/BvrS of Brucella is an global regulator capable of interacting with other regulators, by controlling the synthesis of components of the cell envelope and outer membrane, metabolism of carbon and nitrogen, and of other genes related to the virulence of the bacteria. In this way, the bacteria may sense when they enter a eukaryotic host cell and thus control the expression of a set of genes which allows them to develop during this intracellular phase of their life cycle.

Further reading: Brucella: Molecular Microbiology and Genomics

from Marcos Mancilla writing in Brucella: Molecular Microbiology and Genomics:

The genomic islands (GIs) are DNA sequences of several kilobases (kb) that contain genes conferring adaptive advantages to the host bacteria. Despite the enclosed intracellular lifestyle, the sequence analysis of Brucella has revealed the presence of various GIs scattered through its genome, a fact that strongly suggests the acquisition of DNA by horizontal transfer events. In addition, the analysis of the genetic content of these regions indicates that they might represent a source of virulence factors. Recently, it has been demonstrated that some predicted GIs are unstable and can be excised from the chromosome by recombination. This experimental evidence points out the foreign origin of such loci and suggests an explanation for the polymorphism related to these large chromosomal regions exhibited by Brucellae.This chapter summarizes the advances in the identification and characterization of Brucella GIs. A detailed analysis of their genetic content and its relation to pathogenicity is also included. Recent data obtained for GI instability is discussed in the context of genome plasticity and virulence attenuation observed in smooth Brucellae.

Further reading: Brucella: Molecular Microbiology and Genomics

from Esteban Chaves-Olarte, Caterina Guzmán-Verri, Eustache Paramithiotis, and Edgardo Moreno writing in Brucella: Molecular Microbiology and Genomics:

Members of the genus Brucella infect and cause disease in a wide variety of mammals, including humans. Despite this host diversity, the clinical and pathological manifestations of brucellosis seem to be conserved within certain range, being the reproductive tract the main target of infection. The pathogenesis of brucellosis is dependent on the ability of the bacterium to invade and replicate within the endoplasmic reticulum of epithelial and phagocytic cells. From this perspective, the use of comprehensive system biology approaches, like proteomics, has contributed to dissect and unravel some aspects of the life cycle of Brucella organisms. In this review, we describe the advantages and limitations of the proteomic approaches employed in the field of brucellosis to discern, at the cellular and the molecular level, the pathogenesis of brucellosis. The emerging picture is that of a pathogen that does not rely on discrete virulence determinants to establish successful infections, but rather of a microbe that utilizes synchronized complex metabolic and signaling systems to reach its replicating niche at the endoplasmic reticulum of host cells. These systems include secretion machineries like the type IV secretion VirB system and signaling complexes like the two component regulatory BvrR/BvrS system and the quorum sensing transcriptional regulator VjbR, all of which have a profound impact on the metabolic state of the bacterium and particularly on the homeostasis of the cell envelope. In addition, we also discuss how the systematic comparison at the proteomic level of different strains, species and mutants within the Brucella genus has improved the experimental approaches used for diagnosis, taxonomy and phylogeny.

Further reading: Brucella: Molecular Microbiology and Genomics

from Bruno W. Sobral and Alice R. Wattam writing in Brucella: Molecular Microbiology and Genomics:

Brucella species are characterized by extremely high levels of nucleotide similarity and yet vary in microbial and disease phenotypes, as well as in pathogenicity and host preference. These variations initially resulted in classification of six species; B. abortus, B. canis, B. melitensis, B. neotomae, B. ovis and B. suis. The lack of sequence diversity has inhibited molecular studies, but the development of new techniques and the recent availability of genome sequences have revealed interesting differences, including the expansion of the known Brucella species.

Further reading: Brucella: Molecular Microbiology and Genomics

from Holger C. Scholz, Peter Kämpfer and Axel Cloeckaert writing in Brucella: Molecular Microbiology and Genomics:

The genus Brucella belongs to the class Alphaproteobacteria which is one of the largest and diverse groups within the phylum Proteobacteria. Comparative genome analysis revealed that Brucella is genetically related to plant-associated symbionts and pathogens. The genus Ochrobactrum, consisting of saprophytes that occasionally infect humans, is the closest phylogenetic neighbour. For many years, the taxonomy of Brucella remained unchanged. The recent development of new molecular typing methods and comparative genome analysis however, has resulted in rapid advances in the understanding of Brucella diversity and, after many years of stagnancy, a process of expansion of the genus is in progress. The recent increased occurrence of novel atypical Brucella strains and novel species poses a new challenge to the characterization, classification and nomenclature of the genus Brucella. Genome sequencing projects of these new isolates have been initiated to obtain a better understanding of biology (including pathogenicity) and evolution of members of the genus Brucella.

Further reading: Brucella: Molecular Microbiology and Genomics

from Nieves Vizcaíno and Axel Cloeckaert writing in Brucella: Molecular Microbiology and Genomics:

The particular characteristics of the Brucella outer membrane (OM) are considered to importantly contribute to the biological properties of these bacteria that are able to survive in the hostile environment of phagocytes and cause persistent infections in diverse mammals. This contrasts with theBrucella's closest relatives in the genus Ochrobactrum which are only occasionally associated to opportunistic infections. High hydrophobicity, resistance to complement, bactericidal cationic peptides, detergents or EDTA, resistance to macrophage degradation or the protection against the host immune response are characteristics related to the Brucella OM. The O-polysaccharide chains of the smooth lipopolysaccharide (S-LPS) are a key component for the virulence of smooth strains but, since naturally rough B. canis and B. ovis that lack O-chains in the LPS are virulent in their respective natural hosts, other traits must have a significant role in virulence. Heterogeneity in LPS, OM proteins, and phospholipids draw a particular OM for each Brucellaa species (in some instances at the biovar or strain level) with a definite composition and topology. This variability leads to modifications in the antigenic and functional properties that could affect the interaction with the host and be related to the differences in pathogenicity and host tropism among the Brucellae.

Further reading: Brucella: Molecular Microbiology and Genomics

from Matthieu Terwagne, Sophie Uzureau, and Jean-Jacques Letesson writing in Brucella: Molecular Microbiology and Genomics:

Quorum sensing is a regulatory system that allows bacteria to coordinate gene expression according to the local population density. Recently, we demonstrated that the virulence of the facultative intracellular bacteria Brucella depends on quorum sensing. Similar to other Gram negative bacteria, Brucellaquorum sensing utilizes the production and detection of N-acyl homoserine lactone as a signal. However, in Brucella, N-acyl homoserine lactone could serve to monitor the confinement state, a situation in which a single bacterium enclosed in a vacuole can be the quorum. Here, we present a current review covering the intricacies of quorum sensing in Brucella, highlighting the abilities of quorum sensing to influence both Brucella virulence and metabolism.

Further reading: Brucella: Molecular Microbiology and Genomics