Entropy and enthalpy convergence of hydrophobic solvation beyond the hard-sphere limit.
Entropy and enthalpy convergence of hydrophobic solvation beyond the hard-sphere limit.
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超出硬球极限的疏水溶剂化的熵和焓收敛。
DOI：
10.1063/1.3530585
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发表时间：
2011
期刊：
影响因子：
--
通讯作者：
R. Netz
中科院分区：
文献类型：
--
作者：
F. Sedlmeier;D. Horinek;R. Netz
实验上已知的不同小疏水溶质在普遍温度下溶剂化熵和焓的收敛似乎表明疏水溶剂化是由普遍的水特征决定的，而不是由溶质特性决定的。一组不同的蛋白质在与疏水溶质大致相同的温度下变性熵的收敛表明，蛋白质的变性熵是由疏水效应主导的，并用于估计疏水对蛋白质稳定性的贡献。然而，这一吸引人的图景随后受到质疑，因为最初声称的变性熵的普遍收敛只适用于一小部分蛋白质；对于较大的数据集，没有发现收敛。我们报告了具有不同溶质-水势的小球形溶质在显式水中溶化的广泛模拟结果。我们发现不同半径的溶质的溶剂化性质存在收敛性，但收敛温度敏感地取决于溶质-水势特征，如排斥部分的刚度和吸引力强度，而不是吸引力范围。因此，只有同源系列的溶质在一种亚基的数量上不同（这证明了溶剂化性质的可加性）或溶质-水相互作用势相似的溶质，溶剂化性质才会收敛。相比之下，对于多肽，可以说是由多个基团组成，与水的相互作用广泛分散，这意味着普遍温度下的热力学收敛通常不能预期，与实验结果一致。
The experimentally well-known convergence of solvation entropies and enthalpies of different small hydrophobic solutes at universal temperatures seems to indicate that hydrophobic solvation is dominated by universal water features and not so much by solute specifics. The reported convergence of the denaturing entropy of a group of different proteins at roughly the same temperature as hydrophobic solutes was consequently argued to indicate that the denaturing entropy of proteins is dominated by the hydrophobic effect and used to estimate the hydrophobic contribution to protein stability. However, this appealing picture was subsequently questioned since the initially claimed universal convergence of denaturing entropies holds only for a small subset of proteins; for a larger data collection no convergence is seen. We report extensive simulation results for the solvation of small spherical solutes in explicit water with varying solute-water potentials. We show that convergence of solvation properties for solutes of different radii exists but that the convergence temperatures depend sensitively on solute-water potential features such as stiffness of the repulsive part and attraction strength, not so much on the attraction range. Accordingly, convergence of solvation properties is only expected for solutes of a homologous series that differ in the number of one species of subunits (which attests to the additivity of solvation properties) or solutes that are characterized by similar solute-water interaction potentials. In contrast, for peptides that arguably consist of multiple groups with widely disperse interactions with water, it means that thermodynamic convergence at a universal temperature cannot be expected, in general, in agreement with experimental results.
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蛋白质折叠的热容依赖性分析。
影响因子：
5.6
作者：
Yang,AS;Sharp,KA;Honig,B
通讯作者：
Honig,B
DOI：
10.1021/jp909048f
发表时间：
2010-02-04
期刊：
The journal of physical chemistry. B
影响因子：
--
作者：
Patel AJ;Varilly P;Chandler D
通讯作者：
Chandler D
DOI：
10.1073/pnas.83.21.8069
发表时间：
1986-11-01
影响因子：
11.1
作者：
BALDWIN, RL
通讯作者：
BALDWIN, RL
固体模型化合物和蛋白质展开的热力学。
影响因子：
5.6
作者：
Murphy,KP;Gill,SJ
通讯作者：
Gill,SJ
DOI：
10.1073/pnas.89.19.9335
发表时间：
1992-10-01
影响因子：
11.1
作者：
FU, L;FREIRE, E
通讯作者：
FREIRE, E