利用ABEEMσπ模型研究哺乳类催产素及其衍生物

Study on Mammalian Oxytocin and Its Derivatives in terms of ABEEMσπ Model

哺乳类催产素及其衍生物是一系列包含S—S键的多肽分子.应用原子-键电负性均衡σπ(ABEEMσπ)模型,我们研究了该系列多肽分子的分子内氢键和整体软度与生物活性关系.首先利用点电荷模型计算了该系列多肽分子的分子内氢键能,并与实验值对比,得到了基本一致的结果.再根据整体软度与生物活性的关系:即整体软度越大,分子生物活性越大,我们成功解释了催产素及其衍生物的分子生物活性的变化关系.将ABEEMσπ模型初步应用于研究含S—S键多肽的相关性质方面,并取得了和实验以及其它理论计算较为一致的结果.因此,以上研究为该模型进一步探讨其它多肽的相关性质提供了一定的理论基础.

Mammalian oxytocin and its derivatives are a series of polypeptides containing S--S bonds. By utilizing ABEEMσπ model （Atom Bond Electronegativity Equalization Method at σπ level）, their properties involving the intra-molecular hydrogen bond （HB） and the global softness are investigated. Firstly, the energies of intra-molecular HB are calculated under the point charge model, which are basically consistent with the experimental and theoretical results. Then, the relationship of molecular bioactivities of mammalian oxytocin and its derivatives is successfully interpreted, according to the fact that the larger global softness corresponds to the stronger bioactivities. In the present work, ABEEMσπ model is tentatively applied to study the related properties of polypeptides with S-S bonds. The results are in basic accordance with the previous experimental and theoretical investigations. Therefore, these studies provide a foundation for extending the ABEEMσπ model to investigate the similar properties of other polypeptides.