Hydrogen bonding in mimics of Watson-Crick base pairs involving C-H proton donor and F proton acceptor groups: A theoretical study
Hydrogen bonding in mimics of Watson-Crick base pairs involving C-H proton donor and F proton acceptor groups: A theoretical study
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DOI：
10.1002/cphc.200301069
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发表时间：
2004-04-15
期刊：
影响因子：
2.9
通讯作者：
Baerends, EJ
中科院分区：
文献类型：
--
作者：
Guerra, CF;Bickelhaupt, FM;Baerends, EJ
我们从理论上分析了沃森-克里克腺嘌呤-胸腺嘧啶（AT）和鸟嘌呤-胞嘧啶（GC）碱基对的模拟，其中N-H…O和N…H-N氢键被N- h…利用密度泛函理论的广义梯度近似，在BP86/TZ2P上分别得到F和N…H-C。上述取代的一般效果是延长和削弱连接碱基对的氢键。然而，精确的影响取决于在AT和GC中有多少氢键被取代，特别是哪些氢键被取代。这项工作的另一个目的是通过使用定量的键能分解方案，阐明在模拟中涉及的弱氢键中，静电吸引与轨道相互作用的相对重要性。与普遍认为的不同，发现这些弱氢键中的轨道相互作用分量贡献了34-42%的吸引力相互作用，因此与静电分量具有一定的数量级，静电分量提供了剩余的吸引力分量。
We have theoretically analyzed mimics of Watson-Crick adenine-thymine (AT) and guanine-cytosine (GC) base pairs in which N-H...O and N...H-N hydrogen bonds ore replaced by N-H...F and N...H-C, respectively, by using the generalized gradient approximation of density functional theory at BP86/TZ2P. The general effect of the above substitutions is an elongation and weakening of the hydrogen bonds that hold together the base pairs. However, the precise effects depend on how many and, in particular, on which hydrogen bonds are substituted in AT and GC Another purpose of this work is to clarify the relative importance of electrostatic attraction versus orbital interaction in the weak hydrogen bonds involved in the mimics, by using a quantitative bond-energy decomposition scheme. At variance with widespread believe, the orbital interaction component in these weak hydrogen bonds is found to contribute 34-42% of the attractive interactions and is thus of the some order of magnitude as the electrostatic component, which provides the remaining attraction component.