Isolation and characterization of MT2617-2B, a phospholipase C inhibitor produced by an actinomycetes isolate = 방선균 분리주가 생산하는 Phospholipase C 저해물질인 MT2617-2B의 분리 및 특성

Abstract

A phospholipase C (PLC) inhibitor (MT2617-2B) was isolated from the culture broth of actinomycetes isolate MT2617-2 by the extraction with n-butanol and column chromatographic techniques. The molecular weight of the inhibitor was 1057, by the spectroscopic analyses of IR, 13C- and 1H-NMR and ESI-MS. The chemical structure of MT2617-2B was found to be a macrolide compound consisted of a hemiketal ring, polyhydroxyl and polymethyl groups, which had a malonate and guanidine group as its side chain. MT2617-2B produced its two isomers having the same molecular weight by standing in methanol solution at room temperature. Therefore, MT2617-2B was identified as copiamycin and niphithricin A, macrolide antibiotics. The values of IC50, against PLC-γ1 and PLC-β1 were 25 and 50 μg/ml, respectively. MT2617-2B had antimicrobial activities against Staphylococcus aureus and Candida albicans, but not against Escherichia coli.