The gentamicin antibiotics. VI. Gentamicin C2b, an aminoglycoside antibiotic produced by micromonospora purpurea mutant JI-33

Abstract

A mutant strain of Micromonospora purpurea, designated var. JI-33, produced an antibiotic complex consisting primarily of gentamicin C1a. A further product of this fermentation was identical to a very minor component isolated from the fermentation of the parent organism and named gentamicin C2b. Physical measurements indicated its structure to be 6′-N-methylgentamicin C1a, and this was confirmed by synthesis from gentamicin C1a. The in vitro antibacterial activity of gentamicin C2b was very similar to that of the gentamicin C complex. Antibiotic XK-62-2, produced by Micromonospora sagamiensis, appears to be identical to gentamicin C2b. © 1975, JAPAN ANTIBIOTICS RESEARCH ASSOCIATION. All rights reserved.