【摘要】 将分子模拟方法引入到蛋白质离子交换层析中的静电相互作用研究。选用蛋清溶菌酶和牛胰凝乳蛋白酶为模型蛋白质,阳离子交换吸附剂SP Sepharose FF等为模型层析介质。从蛋白质数据库(PDB)中获得蛋白质三维结构数据,分析了介质孔径和配基分布,以点电荷模拟离子交换层析介质的功能配基,构筑了蛋白质-介质配基模拟表面体系。采用MCCE、Delphi和GRASP等程序包进行了分子模拟计算,考察了作用方向、作用距离、盐浓度、pH等对蛋白质和模拟配基平面间静电相互作用的影响。结果表明,宏观的层析平衡常数与微观分子模拟计算的相互作用能量参数间存在良好的线性关系。更多还原

【Abstract】 The molecular simulation was introduced to study the electrostatic interaction in ion exchange chromatography.Two proteins,lysozyme and a-chymotrypsinogen,was chosen as model separation targets.The cation exchangers with the function groups of SP and CM were investigated in the present work.The 3D structural information of proteins was obtained from the public resource of Protein Data Bank,and suitable data were chosen after comparison.Based on the analysis of pore radius and ligand distribution of ion exchangers,the charge point net was used to construct a simulated system of protein adsorbent and porous surface of ion exchangers.The programs of MCCE、Delphi and GRASP are used to calculate the electrostatic interactions.Some factors,such as the interaction orientation,separation distances,salt concentration and pH,were investigated systematically.The results indicated that there was a good linear relation between the binding energy from electrostatic calculations and equilibrium constant K from chromatographic retention experiments.更多还原