Subcellular localization of enzymes inStreptomyces aureofaciens and its alteration by benzyl thiocyanate

The localization of anhydrotetracycline oxygenase and glucose-6-phosphate dehydrogenase (EC 1.1.1.49) was studied by determining the enzyme activities in subcellular fractions obtained by differential centrifugation of the mycelia of Streptomyces aureofaciens after lysozyme treatment. Glucose-6-phosphate dehydrogenase was a typical cytoplasmic enzyme both in the low- and high-production strain. Anhydrotetracycline oxygenase was found in the membrane fraction of the low-production strain. In the high-production strain, it was detected in several fractions, the highest activity being found in cytoplasm. The presence of 10 microM benzyl thiocyanate in the culture medium significantly changed the distribution of the latter enzyme in both strains. The redistribution of the enzymes is discussed with respect to tetracycline over-production.