Molecular-level organization of saturated and polyunsaturated fatty acids in a phosphatidylcholine bilayer containing cholesteral
Molecular-level organization of saturated and polyunsaturated fatty acids in a phosphatidylcholine bilayer containing cholesteral
复制标题
DOI：
10.1021/bi048231w
复制
发表时间：
2004-12-14
期刊：
影响因子：
2.9
通讯作者：
Feller, SE
中科院分区：
文献类型：
--
作者：
Pitman, MC;Suits, F;Feller, SE
在20 ns的分子动力学计算机模拟的脂质双层膜组成的胆固醇和1-硬脂酰-2-二十二碳六烯酰-sn-甘油-3-磷酸胆碱（SDPC）在1：3的比例在原子水平上的胆固醇的偏好特定的脂肪酸链进行了研究。这些模拟重现实验测量表明，胆固醇更喜欢被饱和酰基链溶剂化，并具有低亲和力的多不饱和脂肪酸。模拟轨迹的分析提供了一个详细的图片的横向和横向结构的脂质双层膜，沿着与描述的脂质和胆固醇的动力学在高时间分辨率。与以前的模拟的纯磷脂双分子层的比较，允许在膜结构和动力学的变化，从掺入胆固醇的原子水平的描述。所观察到的差分胆固醇与饱和和多不饱和脂质的相互作用提供了一种机制，形成横向不均匀的膜，因此，模拟提供了分子水平的深入了解脂筏的形成。
Cholesterol's preference for specific fatty acid chains is investigated at the atomic level in a 20 ns molecular dynamics computer simulation of a lipid bilayer membrane consisting of cholesterol and 1-stearoyl-2-docosahexaenoyl-sn-glycero-3-phosphocholine (SDPC) in a 1:3 ratio. These simulations reproduce experimental measurements suggesting that cholesterol prefers to be solvated by saturated acyl chains and has a low affinity for polyunsaturated fatty acids. Analyses of the simulation trajectory provide a detailed picture of both the transverse and lateral structures of the lipid bilayer membrane, along with a description of lipid and cholesterol dynamics at high temporal resolution. Comparison with a previous simulation of a pure phospholipid bilayer allows an atomic-level description of the changes in membrane structure and dynamics resulting from incorporation of cholesterol. The observed differential cholesterol interactions with saturated and polyunsaturated lipids provide a mechanism for the formation of laterally inhomogeneous membranes; thus, the simulation provides molecular-level insight into the formation of lipid rafts.