Streptomyces

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Streptomyces

Slide culture of a Streptomyces sp.

Scientific classification

Domain:	Bacteria
Phylum:	Actinobacteria
Order:	Actinomycetales
Family:	Streptomycetaceae
Genus:	Streptomyces Waksman & Henrici 1943

Species

S. ambofaciens
S. achromogenes
S. avermitilis
S. coelicolor
S. clavuligerus
S. felleus
S. ferralitis
S. filamentosus
S. griseus
S. hygroscopicus
S. iysosuperficus
S. lividans
S. noursei
S. scabies
S. somaliensis
S. thermoviolaceus
S. violaceoruber
plus ~500 additional species.

Streptomyces is a genus of Actinobacteria, a group of Gram-positive and generally high GC-content bacteria.^[1] Streptomycetes are found predominantly in soil and in decaying vegetation, and most produce spores. Streptomycetes are noted for their distinct "earthy" odor which results from production of a volatile metabolite, geosmin.

Streptomycetes are characterised by a complex secondary metabolism.^[1] They produce a large number of antibiotics that are in clinical use (Neomycin, Chloramphenicol); the now rarely used streptomycin takes its name directly from Streptomyces. Streptomycetes are infrequent pathogens, though infections in human such as mycetoma can be caused by S. somaliensis and in plants such as scabies.

1 Genomics
2 Streptomyces in biotechnology
3 Streptomyces in medicine
4 Books about Streptomyces
5 References
6 See also
7 External links

[edit] Genomics

The complete genome of one of the strain, S. coelicolor A3(2), was published in 2002.^[2] At the time, the S. coelicolor genome contained the largest number of genes of any bacterium. The genome sequence of S. avermitilis was completed in 2003.^[3] This is the first complete genome sequence of the industrial microorganism. Both of these genomes comprise a single chromosome that is linear, unlike most bacterial genomes which comprise a circular chromosome. The genome sequence of S. scabies, a member of the genus with the ability to cause potato scab disease, has been determined at the Wellcome Trust Sanger Institute and is currently in annotation, with publication scheduled for 2007.

Taxonomically, S. coelicolor A3(2) is a sub-species of S. violaceoruber; don't mistake S. coelicolor A3(2) for S. coelicolor (Müller) (ATCC 23899).

[edit] Streptomyces in biotechnology

In recent years, biotechnology researchers have begun to use Streptomyces spp. for production of recombinant human proteins. Traditionally, Escherichia coli was the species of choice to host eukaryotic genes since it was well understood and easy to work with.^[4]^[5] However, E. coli introduces problems such as incorrect (or lack of) glycosylation and incorrect protein folding, resulting in insolubility and loss of bioactivity of the product.^[6] Streptomyces spp. on the other hand have the ability to secrete correctly folded recombinant proteins into the medium after production simplifying the subsequent purification steps. These properties among others make Streptomyces spp. an attractive alternative to other bacteria such as E. coli and Bacillus subtilis.

[edit] Streptomyces in medicine

The clinically important antifungal drug nystatin is derived from Streptomyces noursei. It was discovered in 1950 by Elizabeth Lee Hazen and Rachel Fuller Brown who were doing research for the Division of Laboratories and Research of the New York State Department of Health.

[edit] Books about Streptomyces

The history of Streptomyces research from the beginnings to the most recent applications of genome technology is beautifully explained in the book by Prof. Sir David A. Hopwood who has been at the forefront of this research until very recently. ^[7]. This book introduces many of the researchers and explains very clearly the science, the techniques and the future aims of the research.

[edit] References

^ ^a ^b Madigan M; Martinko J (editors). (2005). Brock Biology of Microorganisms, 11th ed., Prentice Hall. ISBN 0-13-144329-1.
^ Bentley SD, et al. (2002). "Complete genome sequence of the model actinomycete Streptomyces coelicolor A3(2).". Nature 417: 141–147. PMID 12000953.
^ Ikeda H; Ishikawa J; Hanamoto A; Shinose M; Kikuchi H; Shiba T; Sakaki Y; Hattori M; Omura S (2003). "Complete genome sequence and comparative analysis of the industrial microorganism Streptomyces avermitilis.". Nat. Biotechnol. 21: 526–531. PMID 12692562.
^ Brawner M, Poste G, Rosenberg M, Westpheling J (1991). "Streptomyces: a host for heterologous gene expression". Curr Opin Biotechnol 2 (5): 674-81. PMID 1367716.
^ Payne G, DelaCruz N, Coppella S (1990). "Improved production of heterologous protein from Streptomyces lividans". Appl Microbiol Biotechnol 33 (4): 395-400. PMID 1369282.
^ Binnie C, Cossar J, Stewart D (1997). "Heterologous biopharmaceutical protein expression in Streptomyces". Trends Biotechnol 15 (8): 315-20. PMID 9263479.
^ Hopwood D A. (2007). Streptomyces in Nature and Medicine: The Antibiotic Makers. Oxford University Press. ISBN 0-13-978-0-19-515066-7.