Non-specific acetyl-CoA carboxylase and methylmalonyl-CoA carboxyltransferase in Streptomyces noursei var. polifungini.
1. Acetyl-CoA carboxylase (EC 6.4.1.2) and methylmalonyl-CoA carboxyltransferase (EC 2.1.3.1) have been isolated from mycelia of Streptomyces noursei var. polifungini, and purified about 50-fold. 2. Both enzymes carboxylate acetyl-CoA and propionyl-CoA; the respective Km values are 1.1 and 1.6 mM with acetyl-CoA carboxylase and 2.5 and 1.25 mM with carboxyltransferase. 3. The activities of both enzymes are inhibited by free fatty acids. Almost total inhibition of methylmalonyl-CoA carboxyltransferase was observed by 0.1 mM-butyrate or 0.1 mM-C14-C18 acids. Acetyl-CoA carobxylase was affected to the same extent by these compounds at concentration of about 1 mM. 4. The role of both carboxylating enzymes is biosynthesis of the antibiotic is discussed.
D000103:Acetyl-CoA Carboxylase / Q000302:isolation & purification / Q000378:metabolism*; D005230:Fatty Acids, Nonesterified / Q000494:pharmacology; D007700:Kinetics; D008025:Ligases / Q000378:metabolism*; D008970:Molecular Weight; D013302:Streptomyces / Q000201:enzymology*; D014166:Transferases / Q000302:isolation & purification / Q000378:metabolism*
D005230:Fatty Acids, Nonesterified; D014166:Transferases; D008025:Ligases; D000103:Acetyl-CoA Carboxylase