Isolation and structure determination of novamethymycin, a new bioactive metabolite of the methymycin biosynthetic pathway in Streptomyces venezuelae

Novamethymycin (9), a novel macrolide antibiotic, was isolated from Strepto myces venezuelae, the producer of methymycin (4) and neomethymycin (5). Spe ctroscopic analysis of 9 indicated that it is highly related to 4 and 5 but contains hydroxy groups at both C-10 and C-12 on the macrolactone ring. Bi oconversion studies using the PikC cytochrome P450 hydroxylase demonstrated that 4 is converted to 9, further broadening the remarkable substrate flex ibility of this enzyme.