The Incorporation of Elaidate, Oleate and Straight-chain Saturated Fatty Acids by Mycoplasma Strain Y

摘要

Summary: Mycoplasma strain Y grew well in a partly defined medium containing charcoal-treated bovine serum albumin (BSA) with added elaidate, elaidate plus oleate, or elaidate plus a saturated fatty acid containing 10 to 15, 22 or 24 carbon atoms. With elaidate plus a saturated acid containing 16 to 20 carbon atoms there was good growth after a variable lag period. When elaidate was the only fatty acid supplied it comprised from 93 to 95% of the total fatty acids in stationary-phase mycoplasmas, the remainder being derived from contaminating fatty acids in the medium. There was no isomerization of elaidate to oleate. When grown with elaidate plus a shorter-chain saturated acid (C10, C12) or with a long-chain acid (C22, C24), elaidate was incorporated preferentially during the early stages of growth, increasing proportions of the saturated acids being incorporated during the later stages. When grown with elaidate plus a saturated acid of intermediate chain length (C14 to C16), or with elaidate plus oleate, both fatty acids were incorporated in approximately equal proportions throughout growth. The preferential incorporation of elaidate in the early growth stages with some pairs of fatty acids is explained by a competition between the two fatty acids for the BSA binding sites.