Fogacin, a novel cyclic octaketide produced by Streptomyces strain Tu 6319

Abstract

A new octaketide named fogacin (1) was isolated from Streptomyces sp. (strain T 6319). Furthermore two shunt metabolites, SEK4b (2) and anhydroSEK4b (3), were detected and identified as nonenzymatically cyclized products of polyketide intermediates built during the biosynthesis of actinorhodin. SEK4b (2) as well as anhydroSEK4b (3) were previously described as metabolites of genetically engineered strains.