CAJ | 학술논문

采用B3LYP/DZP++的方法研究了第一水化层作用和连续化处理的水溶剂作用对鸟嘌呤-胞嘧啶(GC)碱基对和腺嘌呤-胸腺嘧啶(AT)碱基对质子转移反应的影响。 GC和AT碱基对在连续化水溶剂作用下,均发生单质子转移(SPT1)和分步的双质子转移(DPT),而在第一水化层5个水分子的作用下(GC?5H2O, AT?5H2O)或同时考虑第一水化层作用和连续化水溶剂作用(GC?5H2O+PCM, AT?5H2O+PCM)时, GC和AT碱基对的质子转移均只得到单质子转移反应(SPT1)。单质子转移过程中的活化能变化情况表明：第一水化层对GC和AT碱基对结构和质子转移影响较大,水环境对碱基对的作用主要发生在第一水化层。
채용B3LYP/DZP++적방법연구료제일수화층작용화련속화처리적수용제작용대조표령-포밀정(GC)감기대화선표령-흉선밀정(AT)감기대질자전이반응적영향。 GC화AT감기대재련속화수용제작용하,균발생단질자전이(SPT1)화분보적쌍질자전이(DPT),이재제일수화층5개수분자적작용하(GC?5H2O, AT?5H2O)혹동시고필제일수화층작용화련속화수용제작용(GC?5H2O+PCM, AT?5H2O+PCM)시, GC화AT감기대적질자전이균지득도단질자전이반응(SPT1)。단질자전이과정중적활화능변화정황표명：제일수화층대GC화AT감기대결구화질자전이영향교대,수배경대감기대적작용주요발생재제일수화층。
The effects of the first hydration shel and the bulk solvation effects on the proton-transfer processes of guanine-cytosine (GC) and adenine-thymine (AT) base pairs are studied based on density functional theory, using the B3LYP method and DZP++basis set. The proton-transfer mechanisms of the GC and AT base pairs in bulk solvation are first single-proton transfer (SPT1) and stepwise double-proton transfer (DPT). When only the first hydration shel surrounded by five water molecules (GC?5H2O, AT?5H2O), or both the first hydration shel and bulk solvation effects through polarizable continuum model (PCM) (GC?5H2O+PCM, AT?5H2O+PCM) are considered, only the first single-proton-transfer mechanism (SPT1) is found. The proton-transfer activation energies of the GC and the AT base pairs show that the majority of the hydration effects come from the first hydration shel through hydrogen-bond interactions, therefore the first hydration shel greatly influences the base pair structures and proton-transfer mechanism.