在折叠时蛋白质骨干丧失的背景和力场依赖性,使用现实化的变性和本地状态合集
Michael C Baxa1, Esmael J Haddadian, Abhishek K Jha
1Institute for Biophysical Dynamics, The University of Chicago, 929 East 57th Street, Chicago, Illinois 60637, United States.
Journal of the American Chemical Society
|August 30, 2012
概括
蛋白质折叠显著降低了脊柱形状,平均损耗为每残留物0.7-1.1千卡·莫尔. 这项研究使用现实模型量化了构造损失,与之前的估计不同.
科学领域:
- 生物物理学的生物物理.
- 计算生物学 计算生物学
- 蛋白质科学 蛋白质科学
背景情况:
- 蛋白质的稳定性受到折叠过程中结构的损失的关键影响.
- 量化这种损失对于理解蛋白质结构和功能至关重要.
研究的目的:
- 为了准确计算蛋白质折叠时脊柱形状的减少.
- 将计算的损失与以前的估计进行比较,并确定差异的原因.
主要方法:
- 利用经过实验验证的变质状态模型和对变质和原生蛋白质状态的全原子模拟.
- 分析了脊柱二面角分布 (φ,ψ) 以确定形态变化.
- 整合了本地序列偏好,邻居效应和相关的运动.
主要成果:
- 每个残留物的平均脊柱形态损失被计算为0.7-1.1 kcal·mol(-1) 在298 K,这取决于力场.
- 这相当于每个残留物可用的 conformations 减少了 3-7 倍.
- 结果低于许多之前的估计,这是由于使用现实的合奏和包含相关的运动.
结论:
- 计算的 conformational 损失比以前报告的要小,突出了现实的建模的重要性.
- 损失主要取决于当地的蛋白质环境,来自本地状态属性的影响较小.
- 这项工作为蛋白质稳定性的关键因素提供了更准确的量化.
相关概念视频
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The...
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