偶极子势模拟水溶液对酪氨酸电子结构的影响  

Simulation of the effect of water on the electronic structure of tyrosine by dipoles

作　　者：吴丽华[1] 郑浩平[1] 

机构地区：[1]同济大学物理系,上海200092

出　　处：《科学通报》2012年第18期1646-1656,共11页Chinese Science Bulletin

基　　金：国家自然科学基金(30970694)资助

摘　　要：为了更可靠地得到水溶液中蛋白质分子的电子结构,有必要构建水溶液对蛋白质分子电子结构的等效势,这个等效势必须简单、易用.通过第一性原理、全电子、从头计算,构造了水溶液对酪氨酸(Tyr)电子结构的等效势.工作分为三步:(1)用"自由团簇计算法"计算一个含酪氨酸和水分子的系统的能量最低时的空间结构;(2)基于第一步的空间结构,用"团簇埋入自洽计算法"计算酪氨酸在以水分子为外势条件下的电子结构;(3)用"团簇埋入自洽计算法"计算酪氨酸在用偶极子势代替水分子势条件下的电子结构.结果显示,由于水溶液的存在,酪氨酸电子结构的两个能级平均降低了约0.0158 Ry,其他6个能级平均上升约0.0302 Ry;水溶液对酪氨酸电子结构的影响可以很好地被偶极子势模拟.It is necessary to construct a simple, easy-to-use equivalent potential of water for the electronic structure of protein in order to calculate the electronic structures of proteins in solution more reliably. The first-principles, all-electron, ab initio calculations have been performed to simulate the effect of water on the electronic structure of tyrosine （Tyr）. The process involved three steps： firstly, search for the minimum-energy configuration of the system Tyr＋7H20; secondly, calculate the electronic structure of Tyr with the potential of water molecules via the self-consistent cluster-embedding （SCCE） method; finally, simulate the effect of water on Tyr by dipoles. The results show that the major effect of water on the electronic structure of Tyr is to lower the eigenvalues of two orbitals by about 0.0158 Ry on average, and to raise the other six eigenvalues by about 0.0302 Ry on average. The effect of water on the electronic structure of Tyr can be well simulated by dipoles.

关 键 词：酪氨酸 电子结构 水 等效势 团簇埋入自洽计算 

分 类 号：Q517[生物学—生物化学]