Isolation and characterization of mannopeptins, new antibiotics.

New antibiotics, mannopeptins A and B, were isolated from the fermented broth of Streptomyces platensis strain FS-351. Ferrous ion is essential for the antibiotic production, since no productivity was noted with media containing less than 0.11 mM ferrous ion and maximum production was achieved at a concentration of 1.8 mM. The antibiotics are basic glycopeptides with relatively high molecular weight and are similar to ristocetin and vancomycin but can be differentiated from them in view of their chemical composition and chromatographic behavior. The antibiotics were named mannopeptin after the glycopeptide containing mannose.