STUDIES ON THE BIOSYNTHESIS OF BASIC 16-MEMBERED MACROLIDE ANTIBIOTICS, PLATENOMYCINS. IV

BIOSYNTHESIS OF PLATENOMYCINS

Abstract

To elucidate the biosynthetic pathway of platenomycin (PLM), biosynthetic relationships of platenolides I (PL-1) and II (PL-II), 3-O-propionyl-5-O-mycaminosyl platenolides I (PPL-I-MC) and II (PPL-II-MC), 9-dehydro demycarosyl platenomycin (DDM-PLM), demycarosyl platenomycin (DM-PLM) and 4"-deacyl platenomycin (DA-PLM) were examined with growing cultures or the washed mycelium of blocked mutants of Streptomyces platensis subsp. malvinus MCRL 0388, a platenomycin-producing organism. As a result, it was revealed that PLM was biosynthesized from PL-I via DM-PLM and DAPLM along the pathways shown in Chart 1. 4"-Isovaleroyl unit of PLM-A₁ and 4"-propionyl unit of PLM-B₁ were respectively derived from L-leucine and L-isoleucine.