Synthesis of mycocerosic acids from methylmalonyl coenzyme A by cell-free extracts of Mycobacterium tuberculosis var. bovis BCG.
Multimethyl-branched acids extracted from the cells of Mycobacterium tuberculosis var. bovis BCG were identified by combined capillary gas-liquid chromatography and mass spectrometry. These mycocerosic acids consisted of the products expected from elongation of n-C18 and n-C20 primers with methylmalonyl-CoA. A soluble enzyme preparation from M. tuberculosis var. bovis BCG incorporated methylmalonyl-CoA into mycocerosic acids. This incorporation was partially dependent on the addition of arachidoyl-CoA and this primer affected product distribution, indicating elongation of the primer. Maximal incorporation of methylmalonyl-CoA required the presence of both NADPH and NADH together with ATP and Mg2+. Added CoA, FMN, acyl carrier protein, or bovine serum albumin had no effect on the activity in either the presence or absence of ATP and Mg2+. The pH optimum for mycocerosic acid synthesis was 6.2. Under these conditions, methylmalonyl-CoA was incorporated into very long acids which were identified as mycocerosic acids by radio gas-liquid chromatography.
D000214:Acyl Coenzyme A / Q000031:analogs & derivatives*; D005227:Fatty Acids / Q000096:biosynthesis*; D008401:Gas Chromatography-Mass Spectrometry; D007700:Kinetics; D008316:Malonyl Coenzyme A / Q000031:analogs & derivatives* / Q000378:metabolism; D009169:Mycobacterium tuberculosis / Q000378:metabolism*; D013329:Structure-Activity Relationship
D000214:Acyl Coenzyme A; D005227:Fatty Acids; C015357:methylmalonyl-coenzyme A; D008316:Malonyl Coenzyme A; C032992:mycocerosic acid