碱基与氨基酸二肽间的氢键相互作用

对于碱基-蛋白质之间的相互作用,氢键的形成及断裂起着重要的作用.选取7种氨基酸二肽和3种碱基,以它们之间形成单根氢键的体系为研究对象,在ab initioB3LYP/6-311++G(d,p)水平下进行结构优化,MP2/6-311++G(d,p)水平下进行能量的计算.同时应用ABEEMσπ/MM方法优化结构和计算能量.通过改变氢键相互作用区域的静电相互作用参数kH-bond和形成氢键的氢原子与其受体原子的孤对电子之间距离Rlp,H来拟合函数kH-bond(Rlp,H).用所得函数对选取的复合物进行结合能计算,其结果与ab initio方法所得的结果符合的很好.

Hydrogen bond interaction between bases and amino acid dipeptide

The formation and fracture of the hydrogen bond play an important role in me mteracuu,, ul base-protein. This paper selects single hydrogen bond that is formed between seven kinds of amino acid dipeptide and three kinds of as the studied objects. The geometry optimizations are performed at the ab initio B3LYP/6-311WWG（d,P） level. The energy calculations are performed at the MP2/6- 311＋＋G（d,p） level. At the same time, the geometry optimizations and the energy calculations are performed by ABEEMδπ/MM for the same system. Through changing the electrostatic interaction coefficient κH-bond in the hydrogen bond interaction region （HBIR） and the distance Rlp,H between the H that forms hydrogen bond and the lone pair electrons of its receptor atom, we fit the functions κH-bond （Rlp,H）. Using the functions to calculate the binding energy of the complexes, the results corre- spond to the binding energies calculated by ab inito very well.