PHOSPHATIDYLETHANOLAMINE

L-α-Phosphatidylethanolamine from egg yolk has high unsaturated fatty acid content and elicits radical-scavenging activity. L-α-Phosphatidylethanolamine (PE) is a membrane phospholipid and is interconverted to phosphotidylserine in the presence of phosphatidylserine synthase 2. PE is essential for maintaining the structural integrity of membranes. It is the second most abundant phospholipid in animals, plants and yeast and the major lipid in bacteria. It is synthesized in mitochondria in mammals.

Purify the cephalin by dissolving it in EtOH, adding Pb(OAc)2.3H3O (30g in 100mL H2O) until excess Pb2+ is present. Filter off the solid. Pass CO2 gas through the solution until precipitation of PbCO3 ceases. Filter the solid off and evaporate (while bubbling CO2) under vacuum. An equal volume of H2O is added to the residual oil and extracted with hexane. The hexane extract is washed with H2O until the aqueous phase is free from Pb [test with dithizone (2 mg in 100 mL CCl4; Feigel Spot Tests Vol I, Elsevier p. 10 1954)]. The hexane is dried (Na2SO4), filtered and evaporated to give a yellow waxy solid which should be dried to constant weight in vacuo. It is practically insoluble in H2O and Me2CO, but freely soluble in CHCl3 (5%) and Et2O, and slightly soluble in EtOH. [Schofield & Dutton Biochemical Preparations 5 5 1957.]

L-α-Phosphatidylethanolamine from egg yolk has been used:as a component of lipid mixture for the synthesis of giant unilamellar vesicles (GUVs)in ceramide phosphoethanolamine (CPE) synthase assay using crude sphingomyelin synthase-related protein from Hela cellsfor the standard curve generation for the quantification of lipids in plantaris muscle homogenates from mice