M10709, A NEW CYCLIC PEPTIDE ANTIBIOTIC FROM CLINICALLY ISOLATED STREPTOMYCES SP.

A new cyclic heptapeptide, M10709, was isolated from the mycelial cake of a clinically isolated Streptomyces sp. IFM 10709. The planar structure of M10709 was determined on the basis of IR, MS, NMR, and UV spectra. The absolute configuration of alpha-position of amino acid residues in the acid hydrolysate was determined by advanced Marfey's method to be L except that of tryptophan-derived amino acid. The compound showed antibacterial activity against Micrococcus luteus IFM 2066.