title: Repeated polyketide synthase modules involved in the biosynthesis of a heptaene macrolide by Streptomyces sp. FR-008.
abstract: Genes for biosynthesis of a Streptomyces sp. FR-008 heptaene macrolide antibiotic with antifungal and mosquito larvicidal activity were cloned in Escherichia coli using heterologous DNA probes. The cloned genes were implicated in heptaene biosynthesis by gene replacement. The FR-008 antibiotic contains a 38-membered, polyketide-derived macrolide ring. Southern hybridization using probes encoding domains of the type I modular erythromycin polyketide synthase (PKS) showed that the Streptomyces sp. FR-008 PKS gene cluster contains repeated sequences spanning c. 105kb of contiguous DNA; assuming c. 5 kb for each PKS module, this is in striking agreement with the expectation for the 21-step condensation process required for synthesis of the FR-008 carbon chain. The methods developed for transformation and gene replacement in Streptomyces sp. FR-008 make it possible to genetically manipulate polyene macrolide production, and may later lead to the biosynthesis of novel polyene macrolides.
authors: Department of Soil Sciences and Agrochemistry, Huazhong Agricultural University, Wuhan, Hubei, People's Republic of China.
authors: Z
authors: Z
authors: Hu
authors: K
authors: K
authors: Bao
authors: X
authors: X
authors: Zhou
authors: Q
authors: Q
authors: Zhou
authors: D A
authors: DA
authors: Hopwood
authors: T
authors: T
authors: Kieser
authors: Z
authors: Z
authors: Deng
mesh_terms: D000900:Anti-Bacterial Agents / Q000096:biosynthesis*; D002174:Candicidin / Q000031:analogs & derivatives* / Q000096:biosynthesis; D003001:Cloning, Molecular; D003360:Cosmids; D015342:DNA Probes; D004269:DNA, Bacterial / Q000235:genetics / Q000378:metabolism; D004926:Escherichia coli; D005798:Genes, Bacterial; D009097:Multienzyme Complexes / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D005810:Multigene Family; D010957:Plasmids; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000378:metabolism; D012091:Repetitive Sequences, Nucleic Acid; D015183:Restriction Mapping; D013302:Streptomyces / Q000201:enzymology* / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D015342:DNA Probes; D004269:DNA, Bacterial; D009097:Multienzyme Complexes; D011994:Recombinant Proteins; D002174:Candicidin