PALMITOYL-L-CARNITINE, A METABOLIC INTERMEDIATE OF THE FATTY-ACID INCORPORATION PATHWAY IN ERYTHROCYTE-MEMBRANE PHOSPHOLIPIDS

In this paper we report that palmitoyl-L-carnitine can be a metabolic intermediate of the fatty acid incorporation pathway into erythrocyte membrane phosphatidylcholine, and phosphatidhylethanolamine. Phospholipid acylation was evaluated by measuring the incorporation of radioactive [1-14C]-palmitoyl-L-carnitine in membrane erythrocyte ghost phospholipids in the presence or absence of CoA, CoA highly stimulated the incorporation of [1-14C]-palmitic acid into both the phospholipids examined, although the incorporation was also evident in the absence of added CoA. Incorporation of [1-14C]-palmitic acid into phosphatidylcholine was greater than into phosphatidylethanolamine. 2-Bromo-palmitoyl-CoA, an irreversible inhibitor of the erythrocyte carnitine palmitoyltransferase, inhibited the acylation process. © 1990 Academic Press, Inc.