[Formation of organic acids by an active strain of Act. rimosus and by an inactive mutant in relation to oxytetracycline biosynthesis].

Formation of organic acids by an active oxytetracycline-producing strain and an inactive mutant under conditions favourable (starch medium) and unfavourable (glucose medium) for the antibiotic biosynthesis was studied. It was shown that the active strain practically produced no organic acids on the starch medium. Under conditions unfavourable for the antibiotic biosynthesis the decrease in the activity level correlated with accumulation of marked amounts of pyruvic and lactic acids. The mutant possessing no capacity for the antibiotic biosynthesis produced significant amounts of pyruvic, acetic and lactic acids, the amounts of the acids markedly increased on the glucose medium. By the composition of keto acids the active strain and the inactive mutant did not differ.