Gradual Crossover from Subdiffusion to Normal Diffusion: A Many-Body Effect in Protein Surface Water
Gradual Crossover from Subdiffusion to Normal Diffusion: A Many-Body Effect in Protein Surface Water
复制标题
从次扩散到正常扩散的逐渐交叉：蛋白质地表水中的多体效应
DOI：
10.1103/physrevlett.120.248101
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发表时间：
2018
影响因子：
8.6
通讯作者：
Hong Liang
中科院分区：
文献类型：
--
作者：
Tan Pan;Liang Yihao;Xu Qin;Mamontov Eugene;Li Jinglai;Xing Xiangjun;Hong Liang
水化水的动力学对生物大分子的功能至关重要。以往的研究表明，水分子在生物大分子表面表现出次扩散，但其微观机制尚不清楚。在这里，通过对水合的过氚蛋白粉末进行中子散射、分子动力学模拟和解析模拟，我们发现水分子在蛋白质表面的捕获位置之间随机跳跃，等待时间服从广泛的分布，导致二次扩散。此外，由于多体体积排斥效应，次扩散指数随观测时间逐渐增大，趋于正常扩散。
Dynamics of hydration water is essential for the function of biomacromolecules. Previous studies have demonstrated that water molecules exhibit subdiffusion on the surface of biomacromolecules; yet the microscopic mechanism remains vague. Here, by performing neutron scattering, molecular dynamics simulations, and analytic modeling on hydrated perdeuterated protein powders, we found water molecules jump randomly between trapping sites on protein surfaces, whose waiting times obey a broad distribution, resulting in subdiffusion. Moreover, the subdiffusive exponent gradually increases with observation time towards normal diffusion due to a many-body volume-exclusion effect.