Hybrid anthracyclines from a genetically engineered Streptomyces galilaeusmutant

The genetic engineering of antibiotic-producing Streptomyces strains is an approach that is emerging and ready to become established as a successful m ethodology in developing analogues of the original, pharmaceutically import ant, natural products obtained from the organisms. The current report highl ights this success by demonstrating the high-level production of novel anth racyclines. The biosynthetic pathways of the nogalamycin-producing Streptom yces nogalater and the aclacinomycin-producing S. galilaeus were combined b y transferring the genes of S. nogalater polyketide synthetase into a nonpr oducing S. galilaeus mutant. The resulting anthracycline antibiotics that w ere produced possessed structural features characteristic of compounds from both of the undoctored Streptomyces strains.