水的幅度和分子起源在蛋白质旁边减速
Fabio Sterpone1, Guillaume Stirnemann, Damien Laage
1Department of Chemistry, Ecole Normale Supérieure, UMR ENS-CNRS-UPMC 8640, 24 rue Lhomond, 75005 Paris, France. fabio.sterpone@ibpc.fr
Journal of the American Chemical Society
|February 17, 2012
概括
蛋白质水化的动力学减缓了水的运动. 关键因素是蛋白质几何和水-蛋白质键,解释了蛋白质附近的水动态.
科学领域:
- 生物物理学的生物物理.
- 物理化学 物理化学
- 计算生物学 计算生物学
背景情况:
- 补水的动态对于蛋白质的折叠和功能至关重要.
- 蛋白质附近的水动态比散装水慢,但确切的原因仍在争论中.
研究的目的:
- 为了提供蛋白质水化动态的分子描述.
- 为了确定控制水动态的关键蛋白质特征.
- 量化解释观察到的水分子的减速.
主要方法:
- 围绕模型蛋白质 (lyszyme) 进行水动态的数值模拟.
- 使用延伸跳模型进行理论建模.
- 微观地图绘制水的重定向和键 (HB) 动态.
主要成果:
- 80%的水合层水表现出2-3倍的减速;其余的水表现出电力定律行为,与NMR数据相匹配.
- 蛋白质界面上的水的重定向主要是由大角度跳跃,类似于散装水.
- 一个理论模型确定了拓排除体积和水蛋白HB强度作为减速的关键因素.
结论:
- 蛋白质几何和HB强度量化解释了水化的动态.
- 扩展跳跃模型为了解蛋白质附近的水减速提供了一个严格的框架.
- 这些发现提供了关于蛋白质折叠,功能和与水的相互作用的见解.
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