Kambayashi Y, Yamamoto Y, Nakano M
Research Center for Advanced Science and Technology, University of Tokyo, Japan.
Biochem Biophys Res Commun. 1998 Apr 28;245(3):705-8. doi: 10.1006/bbrc.1998.8421.
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.
通过测量1-棕榈酰-2-亚油酰磷脂酰胆碱（PLPC）和PLPC氢过氧化物（PLPC-OOH）的衰减以及亚油酸和亚油酸氢过氧化物的形成，研究了眼镜王蛇毒磷脂酶A2（PLA2）对PLPC脂质体膜中PLPC氢过氧化物（PLPC-OOH）的水解作用。我们证明，当超过25摩尔%的胆固醇掺入PLPC脂质体膜时，PLA2优先水解PLPC-OOH而非PLPC。对于PLPC氢氧化物（PLPC-OH）也获得了类似的结果。这些结果表明，胆固醇将PLPC-O（O）H的亲水性氢过氧基和羟基部分置换到脂质体膜的表面界面，在那里它们更容易被PLA2水解。
