NEW STREPTOTHRICIN-GROUP ANTIBIOTICS, AN-201 I AND II

SCREENING, FERMENTATION, ISOLATION, STRUCTURE AND BIOLOGICAL ACTIVITY

Abstract

Two streptothricin-group antibiotics, AN-201 I and II, were newly discovered and isolated from the culture broth of Streptomyces nojiriensis C-13. These antibiotics were purified by IRC-50 (H⁺) and CM-Sephadex C-50 chromatography, and paper electrophoresis. Structural analysis of AN-201 I and II showed that they were N^β-acetylated derivatives of streptothricin E and D, respectively. They had antibacterial activities against several strains of Escherichia coli, Bacillus subtilis, Micrococcus luteus and Staphylococcus aureus, and showed a strong selective cytotoxic effect on 3T3 cells transformed with SV-40 as compared with their normal cells in a test system in vitro as well as in vivo.