Examination of Mixtures Containing Sphingomyelin and Cholesterol by Molecular Dynamics Simulations.
Examination of Mixtures Containing Sphingomyelin and Cholesterol by Molecular Dynamics Simulations.
复制标题
通过分子动力学模拟检查含有鞘磷脂和胆固醇的混合物。
DOI：
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发表时间：
2017
影响因子：
3.3
通讯作者：
Jeffery B. Klauda
中科院分区：
文献类型：
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作者：
Eric Wang;Jeffery B. Klauda
全原子CHARMM 36（C36）力场用于模拟纯棕榈酰鞘磷脂（PSM）的双层以及PSM和硬脂酰鞘磷脂（SSM）在不同胆固醇浓度（XC）和温度下的二元混合物。C36模拟数据与实验氘阶参数和以前的计算结果吻合良好，提供了证据的实用性的力场可能研究更复杂的膜。在富含胆固醇的膜中，显示面积压缩模量达到2.82 ± 0.08 N/m的大值（XC = 0.50）。表面积/脂质（SA/唇），倾斜角，膜厚度，和酰基链排序显示有很强的依赖性胆固醇浓度。弛豫时间也表明胆固醇依赖性，并表现出强烈的偏好旋转轴向运动的摆动运动。径向分布函数和脂质聚类表明横向有序和氢键，这是长期生活在SM膜之间的密切关系。这些相互作用导致胆固醇在高浓度下的强自缔合，导致屏蔽进一步的SM-胆固醇相互作用。根据以前的结果揭示了SM-SM氢键上的三元组分的重要性，并且在脂筏的建模中是重要的。
The all-atom CHARMM36 (C36) force field is used to simulate bilayers of pure palmitoylsphingomyelin (PSM) as well as binary mixtures of PSM and stearoylsphingomyelin (SSM) at various cholesterol concentrations (XC) and temperatures. C36 simulation data is in good agreement with experimental deuterium order parameters and previous computational results, providing evidence of the utility of the force field for potentially studying more complex membranes. The area compressibility modulus is shown to achieve a large value of 2.82 ± 0.08 N/m in cholesterol-rich membranes (XC = 0.50). Surface area per lipid (SA/lip), tilt angle, membrane thicknesses, and acyl chain ordering are shown to have strong dependencies on cholesterol concentration. Relaxation times also indicate cholesterol dependence and show a strong preference for rotational axial motion over wobbling motion. Radial distribution functions and lipid clustering indicate strong relationships between lateral ordering and hydrogen bonding, which is long lived in SM membranes. These interactions lead to strong self-association of cholesterol at high concentrations, causing shielding from further SM-cholesterol interactions. The importance of a ternary component on SM-SM hydrogen bonds is revealed in light of previous results and is consequential in the modeling of lipid rafts.
影响因子：
3.3
作者：
Klauda, Jeffery B.;Venable, Richard M.;Freites, J. Alfredo;O'Connor, Joseph W.;Tobias, Douglas J.;Mondragon-Ramirez, Carlos;Vorobyov, Igor;MacKerell, Alexander D., Jr.;Pastor, Richard W.
通讯作者：
Pastor, Richard W.
影响因子：
29
作者：
Hla T;Dannenberg AJ
通讯作者：
Dannenberg AJ
影响因子：
3.4
作者：
A. Sodt;R. Pastor;E. Lyman
通讯作者：
A. Sodt;R. Pastor;E. Lyman