Acyl-trafficking in membrane phospholipid fatty acid turnover: the transfer of fatty acid from the acyl-L-carnitine pool to membrane phospholipids in intact human erythrocytes.
In this work we have investigated the transfer of radioactive palmitic acid between membrane phospholipids and acyl-L-carnitines in intact human erythrocytes. During the incubation period of labeled erythrocyte in non-defatted bovine serum albumin, radioactivity in phosphatidylcholine and phosphatidylethanolamine increased. On the contrary, a decrease of radioactivity in erythrocyte palmitoyl-L-carnitine was observed. 2-Tetradecylglycidic acid, an irreversible erythrocyte carnitine palmitoyltransferase inhibitor, abolished any radioactivity changes in both phospholipids and palmitoyl-L-carnitine. Similar findings were obtained by using erythrocytes labeled with radioactive oleic acid. Our data suggest that in human erythrocytes a carnitine palmitoyltransferase-catalyzed acyl transfer from acyl-L-carnitine to phospholipids, rather than a previously described fatty acid transfer from phosphatidylcholine to phosphatidylethanolamine, is operative.
Arduini
A
A
Istituto di Scienze Biochimiche, Università degli Studi G. D'Annunzio, Chieti, Italy.
Tyurin
V
V
Tyuruna
Y
Y
Arrigoni-Martelli
E
E
Molajoni
F
F
Dottori
S
S
Federici
G
G
D002334:Carnitine O-Palmitoyltransferase / Q000037:antagonists & inhibitors / Q000097:blood; D004852:Epoxy Compounds / Q000494:pharmacology; D004910:Erythrocyte Membrane / Q000187:drug effects / Q000378:metabolism*; D005227:Fatty Acids / Q000097:blood* / Q000494:pharmacology; D006801:Humans; D008563:Membrane Lipids / Q000097:blood*; D010172:Palmitoylcarnitine / Q000097:blood*; D010713:Phosphatidylcholines / Q000097:blood; D010714:Phosphatidylethanolamines / Q000097:blood; D010743:Phospholipids / Q000097:blood*
D004852:Epoxy Compounds; D005227:Fatty Acids; D008563:Membrane Lipids; D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines; D010743:Phospholipids; D010172:Palmitoylcarnitine; D002334:Carnitine O-Palmitoyltransferase; C021756:2-tetradecylglycidic acid