Fatty acid biosynthesis in Mycobacterium tuberculosis var. bovis Bacillus Calmette-Guérin. Purification and characterization of a novel fatty acid synthase, mycocerosic acid synthase, which elongates n-fatty acyl-CoA with methylmalonyl-CoA.

摘要: A crude extract from Mycobacterium tuberculosis var. bovis Bacillus Calmette-Guerin was previously shown to incorporate methylmalonyl-CoA into mycocerosic acids, exemplified by 2,4,6,8-tetramethyloctacosanoic acid, and malonyl-CoA n-fatty acids (Rainwater D. L., Kolattukudy, P. E. (1983) J. Biol. Chem. 258, 2979-2985). The presence of several fatty acid synthases with differences in substrate preference product chain length detected the M. bovis. Among them a synthase which purified homogeneity using anion-exchange chromatography, gel filtration, affinity hydroxylapatite chromatography. This elongated long-chain acyl-CoA primers NADPH produce multimethyl-branched acids. enzyme specific for would not It n-C6 n-C20 CoA esters generate primarily corresponding tetramethyl-branched Exogenous [1-14C]acyl-CoA trideuteromethylmalonyl-CoA were incorporated Dodecyl sulfate electrophoresis showed that had molecular weight 238,000, whereas filtration native 490,000, indicating is composed two monomers identical weight. contained an acyl carrier protein-like segment as indicated incorporation [1-14C] pantothenate 238-kDa protein production 1 mol taurine/mol monomer upon hydrolysis performic acid-oxidized enzyme. concluded multifunctional similar well-characterized except specificity.