在设计的跨膜的方向上:朝着右倾角?
Suat Ozdirekcan1, Catherine Etchebest, J Antoinette Killian
1Department of Chemical Biology and Organic Chemistry, Bijvoet Center for Biomolecular Research, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands.
Journal of the American Chemical Society
|November 16, 2007
概括
分子动力学模拟显示,跨膜WALP23的倾斜角度很大. 连锁轨迹改善了与2H NMR的一致性,建议使用GALA方法.
科学领域:
- 计算生物物理学的计算生物物理学
- 膜蛋白的动力学 膜蛋白的动力学
- 分子模拟分子模拟
背景情况:
- 了解跨膜的定向对于膜蛋白的功能至关重要.
- 以前的分子动力学 (MD) 模拟和固态2H NMR研究显示了WALP23方向的差异.
- 小的疏水性不匹配对准确模拟的行为提出了挑战.
研究的目的:
- 为了协调MD模拟和2HNMR数据之间的差异,用于WALP23定向.
- 为了研究轨迹采样对确定定向的影响.
- 改进用于预测基倾斜和亚齐木图角的计算方法.
主要方法:
- 在脂质双层中对WALP23进行了长时间分子动力学 (MD) 模拟.
- 连接多个模拟轨迹以增强统计抽样.
- 从模拟数据计算了2H NMR四极分离的逆向计算,并应用了GALA方法.
主要成果:
- 个别的MD模拟产生了很大的倾斜角度 (>30度) 和缓慢的亚齐木斯通收.
- 连锁轨迹与实验2H NMR四极分裂显著改善了一致性.
- 应用到组合平均分割的GALA方法低估了与连接轨迹 (33.5度) 相比的倾斜角度 (6.5度).
结论:
- 拉方法低估倾斜角可能源于在各种亚齐穆塔尔状态中平均效应.
- 运行多个,扩展的MD模拟对于准确预测定向至关重要.
- 需要进一步的方法改进和实验验证,以确认关于定向动态的发现.
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