[Study of the chemical makeup of the mycelium from an active strain of Act. rimosus and from an inactive mutant in relaiton to oxytetracycline biosynthesis].

Chemical composition of the mycelium of the active and inactive mutants of Act. rimosus grown under conditions favourable for oxytetracycline biosynthesis on the starch or maltose medium and under favourable conditions on the glucose medium was studied. It was shown that according to its chemical composition the above strains did not practically differ. When grown on the starch medium the mycelium of both strains contained great amounts of carbohydrates and comparatively small amounts of nucleic acids and nitrogen. Replacement of starch in the medium by glucose or maltose induced significant changes in the mycelium composition: the synthesis of intracellular polysaccharides was markedly suppressed and the synthesis of nucleic acids and nitrogen containing compounds increased. RNA was the main nucleic acid in both strains on starch and glucose media. The content of DNA was low and did not practically change. The mycelium of both strains contained small amounts of lipids which did not significantly change during the process of cultivation and did not correlate with the antibiotic activity.