计算受体和配体结合自由能的新方法

A new method for calculating binding free energies of receptor and ligand

利用ABEEMσπ浮动电荷力场与连续介质模型相结合的方法,计算了受体和配体的结合自由能.将结合自由能分解为真空中的力场作用项、溶剂化能量以及熵效应.由于ABEEMσπ/MM方法充分考虑了外界环境发生变化引起的体系中各个位点之间的电荷极化,因而极大地提高了结合自由能的计算精度.利用该方法计算的2个复合物的结合自由能与实验值的偏差均小于0.5kJ/mol.

Atom-bond electronegativity equalization method fused into molecular mechanics （ABEEMσπ/MM） as a fluctuating charge （FQ） force field, was combined with the Generalized Born Solvent Accessible surface area （GB/ SA） to calculate the binding free energy of receptor and ligand. The binding free energy is divided into molecular mechanical energy （involving intemal energy, van der Waals energy, and Columbic energy）, solvation energy and entropic effect. Because the charges on atomic, bond and lone pair＇s sites are variable in response to the environment, the binding free energies were well reproduced by the present method compared to the experimental values errors being within 0.5 kJ/mol.