Suzuki Teppei, Sota Takayuki
Integrative Bioscience and Biomedical Engineering, Graduate School of Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku, Tokyo 169-8555, Japan.
J Phys Chem B. 2005 Jun 30;109(25):12603-11. doi: 10.1021/jp050100x.
This paper examines the hydration structure on the surface of beta-ribofuranose in aqueous solution, using the ab initio molecular dynamics method. In particular, we focus on circular hydrogen bond networks involving two ribofuranose oxygens and three water molecules. In our simulations, the circular hydrogen bond networks near the ring oxygen of beta-ribofuranose are found to be significantly influenced by the orientation of the hydroxymethyl group. The arrangements of hydrogen bonds observed in the circular hydrogen bond networks are both homodromic and antidromic. To explain these observations, we analyze the electronic properties of the first-hydration-shell water molecules and the OH groups of beta-ribofuranose, using the centers of their maximally localized Wannier functions. The dipole moments of the proton-accepting first-hydration-shell water molecules in our well-defined circular hydrogen bond networks are found to increase by about 0.3 D compared with that of liquid water, indicating the relatively strong polarization effects created by the interactions between the OH groups of the solute and the surrounding water molecules. Our analysis also implies that circular H-bond networks cannot be fully explained from a simple geometrical point of view.
本文采用从头算分子动力学方法研究了β-呋喃核糖在水溶液中的表面水化结构。特别地，我们关注涉及两个呋喃核糖氧原子和三个水分子的环状氢键网络。在我们的模拟中，发现β-呋喃核糖环氧附近的环状氢键网络受羟甲基取向的显著影响。在环状氢键网络中观察到的氢键排列既有同向的，也有反向的。为了解释这些观察结果，我们使用最大局域化万尼尔函数的中心分析了第一水化层水分子和β-呋喃核糖的OH基团的电子性质。在我们定义明确的环状氢键网络中，质子接受性第一水化层水分子的偶极矩与液态水相比增加了约0.3 D，这表明溶质的OH基团与周围水分子之间的相互作用产生了相对较强的极化效应。我们的分析还意味着，环状氢键网络不能从简单的几何角度得到充分解释。
