【摘要】 在启发式亲脂势HMLP(heuristicmolecularlipophilicitypotential)的基础上提出了分子、分子片段和原子的亲水指标和亲脂指标.计算出了20个天然氨基酸侧链的亲水、亲脂指标和亲水、亲脂表面积,并用线性自由能函数表达氨基酸侧链的溶剂化自由能,?Gsol,=b0+b1Li+b2Hi+b3Si+b4Si.应用线性自由能函数和氨基酸侧链的亲水和亲脂!+-i指标,计算了20个氨基酸残基的3种相转移自由能(蒸气-水、蒸气-正辛醇、正辛醇-水)和正辛醇-水分配系数logPow,取得了与实验值高度一致的良好效果.HMLP的亲水和亲脂指标是HMLP的指标化,扩展了这一方法的使用范围.氨基酸侧链的亲水、亲脂指标和线性自由能函数有望用于生物大分子受体与配体的结合自由能的估算、蛋白质的结构与功能、蛋白-蛋白相互作用和识别的研究.更多还原

【Abstract】 Heuristic molecular lipophilicity potential (HMLP) was applied to the study of lipophilicity andhydrophilicity of 20 natural aminoacid side chains. The HMLP parameters, surface area Ai, lipophilic indicesLi and hydrophilic indices Hi of aminoacid side chains were derived from lipophilicity potential L(r). Theparameters were correlated with the experimental data of phase transfer free energies of vapor-to-water, va-por-to-octanol, and octanol-to-water through a linear free energy equation ?Gsol, =b0+b1Li+b2Hi+ ! ib3Si + b4Si . For all above 3 types of transfer free energies between different medium phases, the HMLP + -parameters of 20 aminoacid side chains provided good descriptions. HMLP is an ab initio quantum chemicalapproach and a structure-based technique. Except for atomic van der Waals radii, there was no other empiri-cal parameter used. The computational results of HMLP have clear physical and chemical meaning andcould provide useful lipophilic and hydrophilic parameters for the studies of proteins and peptides.更多还原