期刊
BIOCHIMIE
卷 88, 期 5, 页码 449-460出版社
ELSEVIER FRANCE-EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER
DOI: 10.1016/j.biochi.2005.10.005
关键词
phosphatidylcholine; Cis double bond; cholesterol alpha-face; cholesterol beta-face; chain order; chain tilt; chain packing
A molecular dynamics simulation of a mono-cis-unsaturated 1-palmitoyl-2-oleoyl-phosphatidylcholine bilayer containing similar to 22 mol% of cholesterol (POPC-Chol) was carried out for 15 ns. An 8-ns trajectory was analysed to determine the effects of Chol on the membrane properties and compare it with that on the fully saturated 1,2-dimyristoyl-phosphatidylcholine bilayer containing similar to 22 mol% of Chol (DMPC-Chol). The study suggests that the experimentally observed weaker effect of Chol on the POPC than DMPC bilayer might result from a different vertical localisation of the Chol hydroxyl group (OH-Chol) in both bilayers: in the POPC-Chol bilayer, OH-Chol is placed similar to 3 angstrom higher in the bilayer interface than in the DMPC-Chol bilayer. Because of the rigid cis double bond in the beta-chain of POPC, Chol fits worse to the POPC-Chol membrane environment and is pushed up, in effect all Chol ring atoms are, on average, located above the double bond. Both in mono-cis-unsaturated and fully saturated PC bilayers, Chol induces stronger van der Waals interactions among the chains, whereas its interactions with the chains are weak. In contrast to DMPC, the smooth alpha-face of the Chol ring lowers the order of POPC chains, whereas the rough P-face increases the order. (c) 2005 Elsevier SAS. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据