Schmidt A B, Fine R M
Biosym Technologies, Inc., Parsippany, NJ 07054, USA.
Biopolymers. 1995 Nov;36(5):599-605. doi: 10.1002/bip.360360505.
A continuum hydration model based upon the atomic charges provided with the CFF91 force field [A. B. Schmidt and R. M. Fine (1994) Molecular Simulation, 13, 347-365] has been extended to the octanol-water transfer. The electrostatic component of the transfer free energy is calculated using the finite-difference solution to the Poisson-Boltzmann equation while the nonpolar contributions are assumed to be proportional to the solute-excluded volume in water. All atomic charges and radii besides the aromatic carbon radius are equal in both solvents. The octanol dielectric constant and the probe radius are the main fitting parameters defining the octanol phase. The model has been tested for 38 organic molecules related to the amino acid residues and generally provides a high accuracy. In particular, the mean unsigned error for N-acetyl amino acid amides is 0.5 kcal/mol.
基于CFF91力场提供的原子电荷的连续介质水化模型[A. B. 施密特和R. M. 法恩（1994年），《分子模拟》，13，347 - 365]已扩展到辛醇 - 水转移。转移自由能的静电成分使用泊松 - 玻尔兹曼方程的有限差分法计算，而非极性贡献则假定与溶质在水中的排阻体积成正比。除芳香族碳原子半径外，所有原子电荷和半径在两种溶剂中均相等。辛醇介电常数和探针半径是定义辛醇相的主要拟合参数。该模型已针对38个与氨基酸残基相关的有机分子进行了测试，总体提供了较高的准确性。特别是，N - 乙酰氨基酸酰胺的平均绝对误差为0.5千卡/摩尔。
