1998 Volume 51 Issue 1 Pages 50-57
The genes for most of the biosynthesis of the kinamycin antibiotics have been cloned and heterologously expressed. Genomic DNA of Streptomyces murayamaensis was partially digested with Mbo I and a library of ∼40 kb fragments in E. coli XL1-BlueMR was prepared using the cosmid vector pOJ446. Hybridization with the act I probe from the actinorhodin polyketide synthase genes identified two clusters of polyketide genes. After transferal of these clusters to S. lividans ZX7, expression of one cluster was established by HPLC with photodiode array detection. Peaks were identified from the kin cluster for dehydrorabelomycin, kinobscurinone, and stealthin C, which are known intermediates in kinamycin biosynthesis. Two shunt metabolites, kinafluorenone and seongomycin were also identified. The structure of the latter was determined from a quantity obtained from large-scale fermentation of one of the clones.