MEMBRANE-LIPIDS OF MYCOPLASMA-FERMENTANS

Membranes of Mycoplasma fermentans, incognitus strain, were isolated b y, a combination of osmotic lysis and sonication. Analysis of membrane lipids revealed, in addition to free and esterified cholesterol, six major polar lipids dominated by a de novo synthesized compound (compou nd X), which accounts for 64% of the total lipid phosphorus. Compound X was labeled by palmitate, but not by oleate. Mass spectrometry and g as liquid chromatography analyses of compound X revealed two molecular species with molecular masses of 1048 and 1076 representing, a dipalm itoyl- and a stearoyl-palmitoyl-glycerodiphosphatidylcholine. Compound X has the ability to stimulate human monocytes to secret TNF alpha an d to enhance the fusion of small unilamellar vesicles with MOLT-3 lymp hocytes.