Streptomyces
Central Carbon Metabolic Pathways in Streptomyces
Category: Bacteria
Central Carbon Metabolic Pathways in Streptomyces
from Geertje van Keulen, Jeroen Siebring and Lubbert Dijkhuizen writing in Streptomyces: Molecular Biology and Biotechnology:
Streptomyces and other actinomycetes are fascinating soil bacteria of major economic importance. They produce 70% of antibiotics known to man and numerous other pharmaceuticals for treatment of, e.g. cancer, a range of infections, high cholesterol, or have immunosuppressive activity. It is not surprising that the multitude of gene clusters encoding for the biosynthesis of known and unknown secondary metabolites in genome sequences of a wide range of actinomycetes have received much attention in the last few years. In contrast, there is much less understanding of primary metabolism and its control in actinomycetes, despite its importance as supply pathways of precursors for secondary metabolite production. Streptomyces: Molecular Biology and Biotechnology describes current information on the central carbon metabolic pathways in streptomycetes, focussing on glycolysis, pentose phosphate pathway, Entner-Doudoroff pathway, gluconeogenesis, and the source of phosphate for phosphorylation reactions. In addition, recent developments providing a greater insight into links with secondary metabolism in Streptomyces are reviewed.
Further reading: Streptomyces: Molecular Biology and Biotechnology
from Geertje van Keulen, Jeroen Siebring and Lubbert Dijkhuizen writing in Streptomyces: Molecular Biology and Biotechnology:
Streptomyces and other actinomycetes are fascinating soil bacteria of major economic importance. They produce 70% of antibiotics known to man and numerous other pharmaceuticals for treatment of, e.g. cancer, a range of infections, high cholesterol, or have immunosuppressive activity. It is not surprising that the multitude of gene clusters encoding for the biosynthesis of known and unknown secondary metabolites in genome sequences of a wide range of actinomycetes have received much attention in the last few years. In contrast, there is much less understanding of primary metabolism and its control in actinomycetes, despite its importance as supply pathways of precursors for secondary metabolite production. Streptomyces: Molecular Biology and Biotechnology describes current information on the central carbon metabolic pathways in streptomycetes, focussing on glycolysis, pentose phosphate pathway, Entner-Doudoroff pathway, gluconeogenesis, and the source of phosphate for phosphorylation reactions. In addition, recent developments providing a greater insight into links with secondary metabolism in Streptomyces are reviewed.
Further reading: Streptomyces: Molecular Biology and Biotechnology
Protein Secretion in Streptomyces
Category: Bacteria
Protein Secretion in Streptomyces
from Tracy Palmer and Matthew I. Hutchings writing in Streptomyces: Molecular Biology and Biotechnology:
The saprophytic lifestyle of Streptomyces requires them to secrete prolific numbers of proteins. For example, inspection of the genome sequence of Streptomyces coelicolor indicates it encodes some 819 proteins with predicted signal peptides. This represents more than 10% of the protein coding genes and is most likely an underestimate. Many secreted proteins are required for nutrient capture, and there is an abundance of secreted hydrolases for the breakdown of complex carbohydrates (including cellulose and chitin), peptides and phospho-compounds. In addition to proteins that are secreted into the milieu, many proteins are covalently anchored to the cell surface by means of either a lipid anchor to the membrane or by covalent attachment to the cell wall through the sortase system. Here we summarise what is known about the different protein secretion systems utilised by Streptomyces, and the mechanisms by which proteins are anchored to the extracellular surface.
Further reading: Streptomyces: Molecular Biology and Biotechnology
from Tracy Palmer and Matthew I. Hutchings writing in Streptomyces: Molecular Biology and Biotechnology:
The saprophytic lifestyle of Streptomyces requires them to secrete prolific numbers of proteins. For example, inspection of the genome sequence of Streptomyces coelicolor indicates it encodes some 819 proteins with predicted signal peptides. This represents more than 10% of the protein coding genes and is most likely an underestimate. Many secreted proteins are required for nutrient capture, and there is an abundance of secreted hydrolases for the breakdown of complex carbohydrates (including cellulose and chitin), peptides and phospho-compounds. In addition to proteins that are secreted into the milieu, many proteins are covalently anchored to the cell surface by means of either a lipid anchor to the membrane or by covalent attachment to the cell wall through the sortase system. Here we summarise what is known about the different protein secretion systems utilised by Streptomyces, and the mechanisms by which proteins are anchored to the extracellular surface.
Further reading: Streptomyces: Molecular Biology and Biotechnology
Differentiation in Streptomyces
Differentiation in Streptomyces: The Properties and Programming of Diverse Cell-types
from Keith F. Chater writing in Streptomyces: Molecular Biology and Biotechnology:
Streptomyces colonies are complex differentiated organisms, generated from a single ovoid spore by filamentous growth and branching. Eventually, much of this biomass is converted to large numbers of spores in long chains on specialised aerial hyphae. During colony development, different cellular compartments have different physiology and metabolism, and exoskeletal and cytoskeletal elements bring about different morphological changes. These cellular differentiating processes are underpinned by a large number of regulatory genes, often operating in cascades. During the transition from biomass accumulation to reproductive development, antibiotics are made, sometimes under the control of developmental regulators.
Further reading: Streptomyces: Molecular Biology and Biotechnology
from Keith F. Chater writing in Streptomyces: Molecular Biology and Biotechnology:
Streptomyces colonies are complex differentiated organisms, generated from a single ovoid spore by filamentous growth and branching. Eventually, much of this biomass is converted to large numbers of spores in long chains on specialised aerial hyphae. During colony development, different cellular compartments have different physiology and metabolism, and exoskeletal and cytoskeletal elements bring about different morphological changes. These cellular differentiating processes are underpinned by a large number of regulatory genes, often operating in cascades. During the transition from biomass accumulation to reproductive development, antibiotics are made, sometimes under the control of developmental regulators.
Further reading: Streptomyces: Molecular Biology and Biotechnology
Streptomyces Conjugative Genetic Elements
Streptomyces Conjugative Genetic Elements
from Jutta Vogelmann, Wolfgang Wohlleben and Günther Muth writing in Streptomyces: Molecular Biology and Biotechnology:
Antibiotic producing actinomycetes contain a huge variety of different plasmids, distinguished in size, topology, replication mechanism and copy number. Some are able to integrate into the chromosome by site specific recombination. With the exception of the huge linear plasmids, Streptomyces plasmids encode only functions involved in replication, stable maintenance and conjugative transfer. The Streptomyces conjugation system is unique, requiring a single plasmid-encoded protein, TraB. TraB is a hexameric ring ATPase with similarity to the septal DNA translocator proteins FtsK/SpoIIIE which are involved in chromosome segregation during cell division and sporulation. TraB binds non-covalently to 8bp TRS repeats present in the clt locus and transfers double stranded plasmid DNA from the donor to the recipient. Presence of clt-like sequences in the chromosome of S. coelicolor suggests that chromosomal genes are mobilized independently from the plasmid. Following primary transfer from the donor into the recipient, the plasmid is translocated via septal crosswalls resulting in intramycelial plasmid spreading. Plasmid spreading involves five to seven plasmid-encoded Spd-proteins. Protein-protein interaction studies with Spd-proteins of the conjugative plasmid pSVH1 suggest formation of a large DNA-translocation apparatus. One component, the integral membrane protein SpdB2 was shown to form pore structures in lipid bilayers.
Further reading: Streptomyces: Molecular Biology and Biotechnology
from Jutta Vogelmann, Wolfgang Wohlleben and Günther Muth writing in Streptomyces: Molecular Biology and Biotechnology:
Antibiotic producing actinomycetes contain a huge variety of different plasmids, distinguished in size, topology, replication mechanism and copy number. Some are able to integrate into the chromosome by site specific recombination. With the exception of the huge linear plasmids, Streptomyces plasmids encode only functions involved in replication, stable maintenance and conjugative transfer. The Streptomyces conjugation system is unique, requiring a single plasmid-encoded protein, TraB. TraB is a hexameric ring ATPase with similarity to the septal DNA translocator proteins FtsK/SpoIIIE which are involved in chromosome segregation during cell division and sporulation. TraB binds non-covalently to 8bp TRS repeats present in the clt locus and transfers double stranded plasmid DNA from the donor to the recipient. Presence of clt-like sequences in the chromosome of S. coelicolor suggests that chromosomal genes are mobilized independently from the plasmid. Following primary transfer from the donor into the recipient, the plasmid is translocated via septal crosswalls resulting in intramycelial plasmid spreading. Plasmid spreading involves five to seven plasmid-encoded Spd-proteins. Protein-protein interaction studies with Spd-proteins of the conjugative plasmid pSVH1 suggest formation of a large DNA-translocation apparatus. One component, the integral membrane protein SpdB2 was shown to form pore structures in lipid bilayers.
Further reading: Streptomyces: Molecular Biology and Biotechnology
Streptomyces Genome
Genome Architecture
from Ralph Kirby and Carton W. Chen writing in Streptomyces: Molecular Biology and Biotechnology
Linear replicons are relatively uncommon among bacteria and their preponderance among the Actinomycetales, and within the Streptomyces in particular, poses some interesting questions. These novel bacterial replicons are capped by terminal proteins that are covalently bound to the 5' ends of the linear DNA and these terminal structures are directly involved in replicating and protecting the ends of the linear genome. In addition and perhaps related to their linear nature, these genomes are among the largest bacterial chromosomes. As far as can be ascertained at present, these large genomes have a specific organizational structure in terms of their genes. The genome structure can be divided into a core region that is present syntenously in most Actinomycetales, two terminal regions that are highly variable throughout the explored Streptomyces and two regions to the left and right of the core region that contain many syntenous genes specific to the Streptomyces and not found in other Actinomycetales. Genome dynamics seems to be important to the Streptomyces with plasmid-chromosome interactions, horizontal gene transfer and interspecific recombination probably playing important roles in how these genomes to adapt to the diverse environment they reside in. Exploring the genome architecture of the Streptomyces helps our understanding of how and why the genus Streptomyces has a unique place in the evolution of the bacteria.
Further reading: Streptomyces: Molecular Biology and Biotechnology
from Ralph Kirby and Carton W. Chen writing in Streptomyces: Molecular Biology and Biotechnology
Linear replicons are relatively uncommon among bacteria and their preponderance among the Actinomycetales, and within the Streptomyces in particular, poses some interesting questions. These novel bacterial replicons are capped by terminal proteins that are covalently bound to the 5' ends of the linear DNA and these terminal structures are directly involved in replicating and protecting the ends of the linear genome. In addition and perhaps related to their linear nature, these genomes are among the largest bacterial chromosomes. As far as can be ascertained at present, these large genomes have a specific organizational structure in terms of their genes. The genome structure can be divided into a core region that is present syntenously in most Actinomycetales, two terminal regions that are highly variable throughout the explored Streptomyces and two regions to the left and right of the core region that contain many syntenous genes specific to the Streptomyces and not found in other Actinomycetales. Genome dynamics seems to be important to the Streptomyces with plasmid-chromosome interactions, horizontal gene transfer and interspecific recombination probably playing important roles in how these genomes to adapt to the diverse environment they reside in. Exploring the genome architecture of the Streptomyces helps our understanding of how and why the genus Streptomyces has a unique place in the evolution of the bacteria.
Further reading: Streptomyces: Molecular Biology and Biotechnology
Streptomyces book
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.
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.
 | 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.