荧光光谱法及物理模建分析小檗淫羊藿甙与清蛋白的分子间作用

Study on the Intermolecular Interaction of Icarrin with Human Serum Albumin Based on Fluorescence Spectrometry and Physical Modeling

光谱分析法结合物理模建研究小檗淫羊藿甙(ICA)与清蛋白(HSA)的分子间作用,采用多种理论方程描述ICA与HSA分子间作用,并比较分析ICA与HSA分子间作用适用模型。运用荧光光谱法研究ICA与HSA的分子间作用。结果表明,ICA与HSA分子间作用具有荧光特征谱,ICA与HSA的分子间作用力使得HSA的荧光强度呈现规律性变迁,说明ICA与HSA确实发生了分子间作用。同步荧光光谱结果表明ICA与HSA的分子间作用使得HSA的微区构象发生改变。利用Lineweaver-Burk方程、双对数回归方程、Scatchard系列方程、Stern-Volmer方程、Lehrer-Fasman方程和Tachiya模型分别描述ICA与HSA的分子间作用,发现不同理论模型描述分子间作用可分为两类定量结果,通过物理模建技术辅助确定ICA与HSA分子间作用模式,得到双对数线性回归方程更符合ICA与HSA分子间作用模型,同时辅助解析ICA与HSA的分子间作用,物理模建结果表明ICA与HSA的分子间作用发生在HSA活性位域Sudlow’s sitesⅠ,且主要是通过范德华力、疏水作用力和氢键发生分子间作用。该研究所得结果可为全面分析ICA与HSA分子间作用机理提供借鉴,也为小分子与生物大分子的分子间作用的理论描述研究提供有益参考。

The intermolecular interaction between Icarrin(ICA)and Human Serum Albumin(HSA)was investigated by spectral method and building molecular model to explore ICA-HSA mechanism of interaction.And the intermolecular interaction model of ICA-HSA was described by using a variety of theoretical equations to compare and discuss their usability.The results showed that the fluorescence intensity of HSA in the fluorescence spectra showed regular decrease,indicating that HSA did interact with ICA.The synchronous fluorescence spectrum showed that micro-conformation of HSA changed due to the intermolecular interaction between ICA and HSA.The intermolecular interactions of ICA-HSA were described using Stern-Volmer equation,Lineweaver-Burk equation,double logarithmic regression equation,Scatchard series equation,Lehrer-Fasman equation and Tachiya model respectively.The results showed that the theoretical model was different and the results were different from ICA-HSA.There are two quantitative kinds of trends based on the differences between hypothesis and experimental conditions.In this paper,physical model was built to assist the intermolecular interaction mode of ICA-HSA.The optimal mode of ICA-HSA intermolecular interaction was the double logarithmic equation.Meanwhile,the ICA-HSA intermolecular interaction was analyzed by physical modeling,indicating that the ICA tend to occurr in active site Sudlow’s sites I and ICA-HSA system mainly has van der Waals force,hydrophobic interaction and hydrogen bonding.These results obtained in this paper serves to provide a reference for the comprehensive analysis of ICA-HSA intermolecular interaction,as well as the theoretical description of the intermolecular interactions between small molecules and biomacromolecules.