Protein hydration, thermodynamic binding, and preferential hydration
Protein hydration, thermodynamic binding, and preferential hydration
复制标题
DOI：
10.1021/bi020316e
复制
发表时间：
2002-11-19
期刊：
影响因子：
2.9
通讯作者：
Timasheff, SN
中科院分区：
文献类型：
--
作者：
Timasheff, SN
蛋白质的水化问题，即蛋白质分子与水的相互作用，以及水分子参与蛋白质反应的问题，在近一个世纪的时间里一直是人们关注的焦点。然而，尽管通过传输(1，2)和核磁共振(3)技术进行了测量，但与蛋白质分子WH(水合作用的水)相互作用的水分子的数量一直难以捉摸。其原因在于蛋白质水合这一物理现象的本质。事实上，蛋白质分子周围没有坚硬的水壳，而是有一团波动的水分子，或多或少受到蛋白质分子热力学上的强烈影响。然而，用整个水分子的有效数量WH来描述整体效应一直是一个有用的概念，类似于德拜-胡克尔理论中中心离子周围云中离子分布的静电双层表示(4)，或用于分析传输现象(沉积、电泳、扩散)的剪切表面(5)。蛋白质反应的特征是，在反应过程中，与水接触的蛋白质的总表面积发生变化。这必须伴随着它与之相互作用的水分子数量的变化，即它的水化程度，ΔWH)WH(产物)-WH(反应物)。这对变构转变是正确的，蛋白质
The question of protein hydration, ie, the interaction of protein molecules with water, and of the involvement of water molecules in protein reactions has been a focus of attention for the good part of a century. Yet the number of water molecules that interact with one protein molecule, WH (waters of hydration), has been an elusive quantity, notwithstanding measurements by transport (1, 2) and NMR (3) techniques. The reason for this lies in the essence of the physical phenomenon of protein hydration. The fact is that there is no rigid shell of water around a protein molecule, but rather there is a fluctuating cloud of water molecules that are thermodynamically affected more or less strongly by the protein molecule. Nevertheless, the description of the overall effect in terms of an effective number of whole water molecules, WH, has been a useful concept, analogous to the electrostatic double layer representation of the ionic distribution in the cloud around a central ion in the Debye-Hückel theory (4), or the surface of shear used in the analysis of transport phenomena (sedimentation, electrophoresis, diffusion)(5).It is characteristic of protein reactions that, during the course of the reaction, the total surface area of the protein in contact with water changes. This must be accompanied by a change in the number of water molecules with which it interacts, ie, its extent of hydration, ΔWH) WH (product)-WH (reactant). This is true of allosteric transitions, protein