Acyl phosphatidylglycerol of Escherichia coli.

Acyl phosphatidylglycerol, isolated from Escherichia coli, has been identified as 3-sn-phosphatidyl-1'-(3'-acyl)-sn-glycerol. The fatty acids of the diacylglycerol moiety of acyl phosphatidylglycerol resemble those of phosphatidylglycerol in composition. However, the monoacylglycerol moiety of this lipid contains more unsaturated fatty acids than the diacylglycerol part of this lipid or other phospholipids in E. coli. Furthermore, the fatty acids present in the monoacylglycerol moiety, were found to contain major amounts of an unsaturated acid identified as 7-tetradecenoic acid by combined gas-liquid chromatography-mass spectrometry. This acid was present only in low concentrations in most phospholipids of E. coli.