The biosynthetic gene cluster of the maytansinoid antitumor agent ansamitocin from Actinosynnema pretiosum.

ABSTRACT: Maytansinoids are potent antitumor agents found in plants and microorganisms. To elucidate their biosynthesis at the biochemical and genetic level and to set the stage for their structure modification through genetic engineering, we have cloned two gene clusters required for the biosynthesis of the maytansinoid, ansamitocin, from a cosmid library of Actinosynnema pretiosum ssp. auranticum ATCC 31565. This is a rare case in which the genes involved in the formation of a secondary metabolite are dispersed in separate regions in an Actinomycete. A set of genes, asm22-24, asm43-45, and asm47, was identified for the biosynthesis of the starter unit, 3-amino-5-hydroxybenzoic acid (AHBA). Remarkably, there are two AHBA synthase gene homologues, which may have different functions in AHBA formation

SUBMITTER: Yu TW 

PROVIDER: S-EPMC123004 | biostudies-literature | 2002 Jun

REPOSITORIES: biostudies-literature