Preferential hydrolysis of oxidized phosphatidylcholine in cholesterol-containing phosphatidylcholine liposome by phospholipase A2.
Hydrolysis of 1-palmitoyl-2-linoleoyl-phosphatidylcholine (PLPC) hydroperoxide (PLPC-OOH) in PLPC liposomal membrane by Crotalus adamanteus venom phospholipase A2 (PLA2) was studied by measuring the decay of PLPC and PLPC-OOH and the formation of linoleate and linoleate hydroperoxide. We demonstrate that PLA2 has a preference to hydrolyze PLPC-OOH over PLPC when more than 25 mole % of cholesterol is incorporated into the PLPC liposomal membrane. Similar results were obtained for PLPC hydroxide (PLPC-OH). These results suggest that cholesterol displaces the hydrophilic hydroperoxyl and hydroxyl moieties of PLPC-O(O)H to the surface interface of the liposomal membrane where they are more accessible to PLA2 hydrolysis.
Kambayashi
Y
Y
Research Center for Advanced Science and Technology, University of Tokyo, Japan.
Yamamoto
Y
Y
Nakano
M
M
D002784:Cholesterol / Q000378:metabolism*; D003435:Crotalid Venoms / Q000201:enzymology / Q000378:metabolism; D006868:Hydrolysis; D019787:Linoleic Acid / Q000378:metabolism; D008041:Linoleic Acids / Q000378:metabolism; D008054:Lipid Peroxides / Q000378:metabolism; D008081:Liposomes / Q000378:metabolism; D010084:Oxidation-Reduction; D010713:Phosphatidylcholines / Q000378:metabolism*; D010741:Phospholipases A / Q000378:metabolism*; D054467:Phospholipases A2
D003435:Crotalid Venoms; D008041:Linoleic Acids; D008054:Lipid Peroxides; D008081:Liposomes; D010713:Phosphatidylcholines; C008285:linoleic acid hydroperoxide; C055402:1-palmitoyl-2-linoleoylphosphatidylcholine; D002784:Cholesterol; D019787:Linoleic Acid; D010741:Phospholipases A; D054467:Phospholipases A2