Lysophosphatidyl ethanolamine, acylation

Lyso-glycerophospholipids Another widely distributed class of lipids, which occurs only in small amounts, is comprised of the lyso-phosphatidyl cholines and lyso-phosphatidyl ethanolamines. These compounds are formed in normal tissue by the action of phospholipase A on phosphatidyl choline and phosphatidyl ethanolamine. The enzyme attacks the fatty acid ester bond in the /3-position, splitting off a monoenoic or polyenoic fatty acid (Tattrie 1959 Hanahan 1960). The naturally occurring a -acyl residues are predominantly saturated. The structures of lysophosphatidyl choline and lysophosphatidyl ethanolamine are given in the following figures ... 

As stressed for the biosynthesis of lecithin, the possibility of alternative pathways should be borne in mind. An example is the demonstration by Mebkl and Lands (1963) of the enzymic acylation of lysophosphatidyl ethanolamine to form phosphatidyl ethanolamine by a reaction similar to that described for the acylation of lysolecitW to form lecithin (Reaction 16). 

Like glycolipids, phospholipids are also a elass of polar lipids. Data in Table 3.2 show that phospholipids in natural rubber are normally below 0.6% w/w. A recent study showed that the major components were phosphatidyl choline (PC) and lysophosphatidyl choline (LPC), as shown in Table 3.5. Other minor components were phosphatidyl ethanolamine (PE), phosphatidyl inositol (PI), lysophosphatidyl inositol (LPI), and metal phosphatidates (MP) or phosphatidic acid (PA). Unlike neutral lipids and glycolipids, the acyl components of phospholipids normally contain very low levels of furanoic acid, except for certain rubber clones. The isolated fatty acids are mainly palmitic, stearic, oleic and linoleic acids. ... 

From the standpoint of practical TLC, this chapter considers the following simple hpids free sterols acyl-, diacyl-, and triacylglycerols free fatty acids methyl esters sterol esters and the following polar lipids phosphatidyl choline, lysophosphatidyl choline, phosphatidyl ethanolamine, phosphatidyl serine, phosphatidyl inositol, sphingoipyelin, cerebrosides, and sulfatides. 

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