Isolation of pure anhydrotetracycline oxygenase from Streptomyces aureofaciens.

Anhydrotetracycline oxygenase was purified to homogeneity from Streptomyces aureofaciens, a producer of tetracycline. The enzyme was purified 60-fold in a 40% yield by a two-step procedure using a combination of hydrophobic chromatography and ion-exchange h.p.

Enzymic degradation of bromoxynil by cell-free extracts of Streptomyces felleus.

A method is described for spectrophotometric monitoring the degradation of the herbicide bromoxynil by cell-free extracts of Streptomyces felleus. The method involves a decrease in absorbance at 286 nm (absorption maximum of bromoxynil) that can be ascribed most probably to the cleavage of the aromatic ring of the bromoxynil molecule. Conditions necessary for measuring this degradation together with physico-chemical features of the degradation indicate that the reaction(s) is seemingly catalyzed by an Fe2+-dependent dioxygenase whose activity was not, however, detected in cell-free extracts of a bromoxynil-sensitive mutant of S.

Partial purification and characterization of anhydrotetracycline oxygenase of Streptomyces aureofaciens.

Anhydrotetracycline oxygenase was purified both by affinity chromatography and by hydrophobic interaction chromatography. Molecular weight of anhydrotetracycline oxygenase was determined to be 115,000 by Sephadex G-200 gel filtration. Using preparative isoelectric focusing the isoelectric point of the enzyme was estimated to be 5.

Inhibition studies of glucose-6-phosphate dehydrogenase from tetracycline-producing Streptomyces aureofaciens.

NAD-linked activity of glucose-6-phosphate dehydrogenase from both low-producing and high-producing strains of Streptomyces aureofaciens was inhibited by ATP, ADP, AMP and Pi. The inhibition constants indicate that ADP was the most potent inhibitor. The NADP-linked activity remained unaffected even at relatively high concentrations of these inhibitors.

Enzymes of secondary metabolism and the biosynthesis of macrolide antibiotics.

Enzymes participating in the biosynthesis of macrolide antibiotics are reviewed. Enzyme activities are known to play a pivotal role in the formation of biologically active compounds. Hence it is essential to understand these enzymes, their properties and regulation.