Isolation and characterization of a novel four-chain ether lipid from Clostridium butyricum: the phosphatidylglycerol acetal of plasmenylethanolamine.

We describe the isolation and characterization of a novel four-chain ether phospholipid in Clostridium butyricum grown on petroselinic acid in the absence of biotin. The results of quantitative analyses of hydrolytic products, selective hydrolysis by mild acid or phospholipase C, 1H-, 13C-, and 31P-NMR, and fast atom bombardment-mass spectroscopy (FABMS) have resulted in the determination of the structure of this lipid as a phosphatidylglycerol acetal of plasmenylethanolamine. Smaller amounts of this lipid have been found in cells grown under similar conditions in the presence of oleic, cis-vaccenic, elaidic or dihydrosterculic acids. It also appears to be present in small amounts in cells grown with biotin. This lipid is structurally related to the more plentiful glycerol acetal of plasmenylethanolamine found in these cells.