[Effect of different forms of nitrogen in the biosynthesis of gentamicin by a Micromonospora purpurea var. violacea 1935 culture].

The effect of different inorganic sources of reduced and oxidized nitrogen on biosynthesis of gentamicin was studied. It was shown that both the ammonium and the nitrate nitrogen were consumed by the antibiotic-producing organism. Out of all the salts tested only ammonium sulfate stimulated the biosynthesis of gentamicin. The positive role of this salt was due to both the ammonium and the sulfogroup, since the presence of the sulfogroup alone in sodium sulfat, magnesium or sulfuric acid resulted only in partial stimulation of gentamicin biosynthesis. Simultaneous addition of sulfuric acid ammonium nitrate which suppressed the antibiotic biosynthesis when used alone was equal to introduction of ammonium sulfate.