Polyunsaturated fatty acids in lipid bilayers: Intrinsic and environmental contributions to their unique physical properties
Polyunsaturated fatty acids in lipid bilayers: Intrinsic and environmental contributions to their unique physical properties
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DOI：
10.1021/ja0118340
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发表时间：
2002-01-16
影响因子：
15
通讯作者：
MacKerell, AD
中科院分区：
文献类型：
--
作者：
Feller, SE;Gawrisch, K;MacKerell, AD
多不饱和脂质是生物膜的重要组成部分，影响脂质的秩序和动态、蛋白质-脂质相互作用和膜传输特性。为了获得多不饱和对膜特性影响的原子水平图像，已经进行了基于量子力学（QM）和经验力场的计算。围绕乙烯基-亚甲基键旋转的扭转能量表面的 QM 计算显示旋转势垒较低，表明其内在的灵活性倾向。基于 QM 和实验数据，开发了多不饱和脂质的经验力场参数，并将其应用于 1-硬脂酰-2-二十二碳六烯酰-sn-甘油-3-磷酸胆碱 (SDPC) 脂质双层的 16 ns 分子动力学 (MD) 模拟。模拟结果与实验数据非常吻合，表明膜中多不饱和烃链具有异常高的构象灵活性。通过模拟对链构象和动力学进行详细分析有助于解释实验数据，并有助于理解多不饱和脂质在生物膜中的独特作用。完整的力场作为支持信息包含在内，可从 http://www.pharmacy.umaryland.edu/faculty/amackere/research.html 获取。
Polyunsaturated lipids are an essential component of biological membranes, influencing order and dynamics of lipids, protein-lipid interaction, and membrane transport properties, To gain an atomic level picture of the impact of polyunsaturation on membrane properties, quantum mechanical (QM) and empirical force field based calculations have been undertaken. The QM calculations of the torsional energy surface for rotation about vinyl-methylene bonds reveal low barriers to rotation, indicating an intrinsic propensity toward flexibility. Based on QM and experimental data, empirical force field parameters were developed for polyunsaturated lipids and applied in a 16 ns molecular dynamics (MD) simulation of a 1-stearoyl-2-docosahexaenoyl-sn-glyerco-3-phosphocholine (SDPC) lipid bilayer. The simulation results are in good agreement with experimental data, suggesting an unusually high degree of conformational flexibility of polyunsaturated hydrocarbon chains in membranes. The detailed analysis of chain conformation and dynamics by simulations is aiding the interpretation of experimental data and is useful for understanding the unique role of polyunsaturated lipids in biological membranes. The complete force field is included as Supporting Information and is available from http://www.pharmacy.umaryland.edu/faculty/amackere/research.html.