Karabemycin, a new antimetabolite of glutamine produced by a strain of streptomycete

Abstract

Karabemycin, a new peptide antibiotic, was isolated from the culture filtrate of Streptomyces sp. AM-6424, a soil isolate. The molecular formula of the antibiotic was determined as C15H24N4O6 on the basis of elemental analysis, FD-mass spectrum and 1H and 13C NMR. Acid hydrolysate of karabemycin contains one mol each of valine, alanine and an unknown amino acid. The antibiotic is active against Gram-positive and -negative bacteria on a synthetic medium. The inhibitory activity is reversed by L-glutamine and L-glutamic acid. © 1983, JAPAN ANTIBIOTICS RESEARCH ASSOCIATION. All rights reserved.