三体疏水相互作用的温度依赖性:平均力,,,热容量和非附加性的潜力
Maria Sabaye Moghaddam1, Seishi Shimizu, Hue Sun Chan
1Protein Engineering Network of Centres of Excellence, Department of Biochemistry, Faculty of Medicine, University of Toronto, Toronto, Ontario M5S 1A8, Canada.
Journal of the American Chemical Society
|January 6, 2005
概括
三甲在水中的疏水相互作用取决于温度. 这些相互作用在低温下是反合作的,但在高温下变得添加或合作,影响蛋白质折叠.
科学领域:
- 物理化学 物理化学
- 计算化学计算化学
- 生物物理学的生物物理.
背景情况:
- 疏水性相互作用对于水性环境中的分子协会至关重要.
- 了解多体疏水效应对于模拟诸如蛋白质折叠之类的复杂系统至关重要.
研究的目的:
- 为了研究温度依赖的三体疏水相互作用.
- 分析这些相互作用的合作性或反合作性.
- 为了确定与三体疏水协会相关的热力学特性,包括热容量.
主要方法:
- 使用TIP4P水模型进行广泛的恒压模拟.
- 在六种不同的温度下分析甲类非极性溶液.
- 计算对对和三体相互作用的平均力 (PMF) 的潜力.
主要成果:
- 三甲的疏水相互作用在低到中等温度的溶解屏障中具有抗合作性.
- 相互作用在高温下过渡到添加剂或轻微合作.
- 在三甲联合后,观察到热容量的显著积极变化,这与常见的预期相反.
结论:
- 疏水性协会的热容 signature 不总是负的,可以是正的.
- 这些发现对理解聚合物形状变化和蛋白质折叠动态有影响.
- 多体疏水相互作用的温度依赖性在分子自组合中起着关键作用.
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