Institute of Structural Mechanics, Bauhaus-Universitt Weimar , Marienstr. 15, D-99423 Weimar, Germany.
Department of Physics, Tampere University of Technology , Korkeakoulunkatu 10, P.O. Box 692, FI-33101 Tampere, Finland.
J Phys Chem B. 2017 Jul 20;121(28):6792-6798. doi: 10.1021/acs.jpcb.7b03888. Epub 2017 Jul 5.
We introduce a novel strategy to quantify the disorder of extended water-water hydrogen-bond (HB) networks sampled in particle-based computer simulations. The method relies on the conformational clustering of the HB connectivity states. We successfully applied it to unveil the fine relationship among the protein dynamical transition in hydrated powder, which marks the activation of protein flexibility at T ≈ 240 K, and the sudden increase in the configurational disorder of the water HB network enveloping the proteins. Our finding links, in the spirit of the Adam-Gibbs relationship, the diffusivity of protein atoms, as quantified by the hydrogen mean-square displacements, and the thermodynamic solvent configurational entropy.
我们介绍了一种新的策略，用于量化基于粒子的计算机模拟中采样的扩展水-水氢键 (HB) 网络的无序性。该方法依赖于 HB 连接状态的构象聚类。我们成功地应用该方法揭示了水合粉末中蛋白质动力学转变之间的精细关系，该转变标志着蛋白质灵活性在 T ≈ 240 K 时的激活，以及包围蛋白质的水 HB 网络的构象无序性的突然增加。我们的发现以 Adam-Gibbs 关系为精神，将蛋白质原子的扩散性（由氢均方位移量化）与热力学溶剂构象熵联系起来。
