A NEW ANTIFUNGAL ANTIBIOTIC, CYSTARGIN: FERMENTATION, ISOLATION, AND CHARACTERIZATION

Abstract

A new sulfur-containing peptide antifungal antibiotic, cystargin, was isolated from the fermentation broth of a new species of genus Kitasatosporia, designated as Kitasatosporia cystarginea. On acid hydrolysis, cystargin (C₆₀H₇₇N₁₉O₁₇S₆) gave equimolar glycine, proline, aspartic acid and arginine. By performic acid oxidation, cysteic acid was detected after hydrolysis. It showed a growth inhibitory activity against various phytopathogenic fungi and inhibition of β-1, 3-glucan synthetase from Saccharomyces cerevisiae.