Streptomyces genome

The completion of the sequence of the two Streptomyces genomes demonstrated that between 5 and 6.6% of the whole genome are directly involved in the biosynthesis of predominantly unknown secondary metabolites (see above). Prior to genome sequencing, a number of reports were published in which cryptic or silent secondary metabolite pathways were identified during the search for gene clusters for known metaboKtes. Hence, the occurrence of... 

Filamentous soil bacteria, including the strains belonging to the genus Streptomyces, have a complex morphological differential and are weU known for their abihty to produce an enormous variety of bioactive secondary metabolites, such as antibiotics and immunosuppressant drags. The entire nucleotide sequences of the Streptomyces genomes of Streptomyces coelicolor [1] and S. avermitilis [7] have... 

Bentley, S.D., Chater, K.F., Cerdeno-Tarraga, A.M. et al. (2002) Complete genome sequence of the model actinomycete Streptomyces coelicolor A3(2). Nature, 417, 141. 

Lautru S, Deeth RJ, Bailey LM, Challis GL (2005) Discovery of a New Peptide Natural Product by Streptomyces coelicolor Genome Mining. Nature Chem Biol 1 65... 

TABLE 2.3. Proteins Encoded in the Genomic Area Covering the str-/sts-Cluster of Streptomyces griseus subsp. griseus DSM 40236 (Accession Code AJ862840) ... 

Many y-butyrolactone receptor homologues have been identified in the genome sequences of Streptomyces. At least 22 out of 33 genes encoding homologues of y-butyrolactone receptors are located close to antibiotic biosynthesis gene clusters or have been shown to regulate antibiotic production. 

Mitomycin C, 1, is a potent antitumor antibiotic discovered by Japanese scientists in fermentation cultures of Streptomyces caespitosus. It has been described as "small, fast and deadly (but very selective)" and has an extraordinary ability to crosslink the complementary strands of the DNA double helix with high efficiency and absolute specificity. It is so lethal that one crosslink per genome is sufficient to cause death of a bacterial cell. Mitomycin C, which is widely used clinically as an antitumor drug, does not react with DNA, but enzymatic reduction of the quinone induces a cascade of transformations which results, ultimately, in formation of the DNA crosslink 2. 

G Hintermann. Aspects of the genomic organisation in Streptomyces glaucescens. PhD dissertation, ETH, Zurich, Switzerland, 1984. 

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