title: A cryptic type I polyketide synthase (cpk) gene cluster in Streptomyces coelicolor A3(2).
abstract: The chromosome of Streptomyces coelicolor A3(2), a model organism for the genus Streptomyces, contains a cryptic type I polyketide synthase (PKS) gene cluster which was revealed when the genome was sequenced. The ca. 54-kb cluster contains three large genes, cpkA, cpkB and cpkC, encoding the PKS subunits. In silico analysis showed that the synthase consists of a loading module, five extension modules and a unique reductase as a terminal domain instead of a typical thioesterase. All acyltransferase domains are specific for a malonyl extender, and have a B-type ketoreductase. Tailoring and regulatory genes were also identified within the gene cluster. Surprisingly, some genes show high similarity to primary metabolite genes not commonly identified in any antibiotic biosynthesis cluster. Using western blot analysis with a PKS subunit (CpkC) antibody, CpkC was shown to be expressed in S. coelicolor at transition phase. Disruption of cpkC gave no obvious phenotype.
authors.affiliation: Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Weigla 12, 53-114 Wroclaw, Poland.
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Pawlik
authors.forename: Magdalena
authors.initials: M
authors.lastname: Kotowska
authors.forename: Keith F
authors.initials: KF
authors.lastname: Chater
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Kuczek
authors.forename: Eriko
authors.initials: E
authors.lastname: Takano
mesh_terms: D000900:Anti-Bacterial Agents / Q000378:metabolism*; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D005810:Multigene Family / Q000235:genetics*; D048630:Polyketide Synthases / Q000235:genetics* / Q000378:metabolism; D048372:Streptomyces coelicolor / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism*
chemical_list: D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; D048630:Polyketide Synthases