Mutational biosynthesis by idiotrophs of Micromonospora purpurea. II. Conversion of non-amino containing cyclitols to aminoglycoside antibiotics.

A mutant of Micromonospora purpurea, which produces the gentamicin complex only when 2-deoxystreptamine is added to the fermentation medium, produces a new antibiotic complex, 2-hydroxygentamicin, when streptamine or 2,4,6/3,5-pentahydroxycyclohexanone is added to the fermentation medium. This mutant also produces the gentamicin complex when 2,4/3,5-tetrahydroxycyclohexanone is added to the fermentation medium. The C1 and C2 components of 2-hydroxygentamicin have broad spectrum in vitro antibacterial activity similar to the gentamicin C1 and C2 components, but with greater activity against some gentamicin-resistant strains.