Rapid Prediction of Solvation Free Energy. 2. The First-Shell Hydration (FiSH) Continuum Model
Rapid Prediction of Solvation Free Energy. 2. The First-Shell Hydration (FiSH) Continuum Model
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DOI：
10.1021/ct9006037
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发表时间：
2010-05-01
影响因子：
5.5
通讯作者：
Purisima, Enrico O.
中科院分区：
文献类型：
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作者：
Corbeil, Christopher R.;Sulea, Traian;Purisima, Enrico O.
溶质周围第一水合壳中水的局部排序与各向同性散装水不同。这导致显式溶剂化模型捕获了显式溶剂化模型捕获的效果，而连续介质溶剂化模型用连续介质取代显式水则忽略了这些效果。在本文中，我们介绍了第一层水合（FISH）模型，作为在连续溶剂化框架内引入第一层效应的首次尝试。其中一种效应是电荷不对称，通过引入基于感应表面电荷密度的原子玻恩半径的非线性校正，通过 FISH 模型中的修改静电项捕获电荷不对称。由两个连续区域组成的混合范德华公式已经被实施。限制在溶剂可及表面 (SAS) 上并均匀分布在溶剂可及表面 (SAS) 上的水壳代表第一个溶剂化壳，从 SAS 一个溶剂直径开始的第二个区域被视为具有均匀密度函数的本体水。 FiSH 模型的静电项和范德华项均已根据分子动力学模拟的线性相互作用能 (LIE) 数据进行了校准。 FiSH 模型在大型水合数据集（包括简单化合物和药物样分子）上进行了广泛的测试。 FiSH 模型准确地再现了贡献项、相对于实验水合自由能的绝对预测以及 LIE MD 模拟的功能类别趋势。总体而言，FiSH 模型的实施实现了非常可接受的性能和可转移性，比以前开发的溶剂化模型有所改进，同时辅以良好的物理基础。
Local ordering of water in the first hydration shell around a solute is different from isotropic bulk water. This leads to effects that are captured by explicit solvation models and missed by continuum solvation models which replace the explicit waters with a continuous medium. In this paper, we introduce the First-Shell Hydration (FISH) model as a first attempt to introduce first-shell effects within a continuum solvation framework. One such effect is charge asymmetry, which is captured by a modified electrostatic term within the FISH model by introducing a nonlinear correction of atomic Born radii based on the induced surface charge density. A hybrid van der Waals formulation consisting of two continuum zones has been implemented. A shell of water restricted to and uniformly distributed over the solvent-accessible surface (SAS) represents the first solvation shell, A second region starting one solvent diameter away from the SAS is treated as bulk water with a uniform density function. Both the electrostatic and van der Waals terms of the FiSH model have been calibrated against linear interaction energy (LIE) data from molecular dynamics simulations. Extensive testing of the FiSH model was carried out on large hydration data sets including both simple compounds and drug-like molecules. The FiSH model accurately reproduces contributing terms, absolute predictions relative to experimental hydration free energies, and functional class trends of LIE MD simulations. Overall, the implementation of the FiSH model achieves a very acceptable performance and transferability improving over previously developed solvation models, while being complemented by a sound physical foundation.