Characterization of the fatty acid synthetase system of Curtobacterium pusillum

Curtobacterium pusillum contains 11-cyclohexylundecanoic acid as a major com-ponent of cellular fatty acids. A trace amount of 13-cyclohexyltridecanoic acid is also present. Fatty acids other than cu-cyclohexyl fatty acids present are 13-methyl-tetradecanoic, 12-methyltetradecanoic, n-pentadecanoic, 14-methylpentadecanoic, 13-methylpentadecanoic, n-hexadecanoic, 15-methylhexadecanoic, 14-methylhex-adecanoic, and «-heptadecanoic acids. The fatty acid synthetase system of this bacterium was studied. Various 14C-labeled precursors were added to the growth medium and the incorporation of radioactivity into cellular fatty acids was analyzed. Sodium [14C]acetate and ["Qglucose were incorporated into almost all species of cellular fatty acids, the incorporation into 11-cyclohexylundecanoic acid being predominant. [14C]Isoleucine was incorporated into 12-methyltetradecanoic and 14-methylhexadecanoic acids; [HC]leucine into 13-methyltetradecanoic and 15-methylhexadecanoic acids; and [14C]valine into 14-methylpentadecanoic acid. [l4C]-Shikimic acid was incorporated almost exclusively into co-cyclohexyl fatty acids. The fatty acid synthetase activity of the crude enzyme preparation of C. pusillum wa