多光谱法和分子对接模拟研究鞣花酸与牛血清蛋白的相互作用  

Studies on Ellagic Acid with Bovine Serum Albumin Interaction Using Multispectraland Molecular Docking Simulation

作　　者：倪丹 蒋新元[2] 庞亚辉 曾胜男 唐玉莲[2] 何思宜 Ni Dan;Jiang Xinyuan;Pang Yahui;Zeng Shengnan;Tang Yulian;He Siyi(College of Science,Central South University of Forestry and Technolgy,Changsha 410004;College of Materials Science and Engineering,Central South University of Forestry and Technolgy,Changsha 410004)

机构地区：[1]中南林业科技大学理学院,长沙410004 [2]中南林业科技大学材料科学与工程学院,长沙410004

出　　处：《中国食品学报》2023年第12期20-28,共9页Journal of Chinese Institute Of Food Science and Technology

基　　金：“十三五”国家重点研发计划项目(2018YFD0600404)。

摘　　要：鞣花酸(EA)是一种具有抗氧化、抗癌、抗突变、抗炎等多种生理活性的天然多酚,鞣花酸与蛋白的相互作用直接影响其在人体的转运与代谢。本文运用多种光谱学方法与分子对接模拟法研究EA与牛血清蛋白(BSA)互作的反应机理。紫外光谱和荧光光谱研究结果表明:EA通过静态方式猝灭BSA的内源荧光,EA与BSA按1.5∶1比例通过自发的放热过程结合,形成稳定的复合物,初步确定其主要作用力为范德华力和氢键。红外光谱和圆二色谱研究表明:EA的加入对BSA的二级结构影响显著,导致BSA中α-螺旋结构减少,β-折叠、β-转角和无规则卷曲结构增加,且EA与BSA间可能存在疏水作用力。分子对接模拟进一步验证了上述光谱分析结果,说明主导EA和BSA结合的作用力除范德华力和氢键外,还有一定的疏水作用力。EA在BSA上的最佳结合位点位于亚结构域ⅡA与亚结构域ⅢA间的疏水空腔内,距离site Ⅰ更近。EA与His145、Pro110、Arg458等残基间存在疏水相互作用,与Arg144残基间存在氢键作用。本研究阐明EA与BSA相互作用的分子机制,为EA在体内转运及代谢研究提供了参考。Ellagic acid(EA)is a natural polyphenol with antioxidant,anti-cancer,anti-mutation,anti-inflammatory and other physiological activities.The interaction between ellagic acid and protein will directly affect its transport and metabolism in the human body.In this paper,a variety of spectroscopic methods and molecular docking simulation methods were used to study the reaction mechanism of the interaction between EA and bovine serum albumin(BSA).The results of UV spectroscopy and fluorescence spectroscopy showed that EA quenched the endogenous fluorescence of BSA in a static manner,EA and BSA combined to form a stable complex through BSA,resulting in the decrease ofα-helix structure and the increase ofβ-sheet,β-turn and random coil structure in BSA.There may be hydrophobic interactions between them.Molecular docking simulation further verifies the results of the above spectral analysis,which shows that in addition to the van der Waals force and hydrogen bond,the dominant force for the binding of EA and BSA also has a certain hydrophobic force.The optimal binding site of EA on BSA is located in the hydrophobic cavity between subdomain IIA and subdomain IIIA,which is closer to site I.There are hydrophobic interactions between EA and residues such as His145,Pro110,and Arg458,and there are hydrogen bonds between residues of EA and Arg144.This study clarified the molecular mechanism of the interaction between EA and BSA,and provided useful information for the study of EA transport and metabolism in vivo.

关 键 词：鞣花酸 牛血清蛋白 多光谱法 分子对接 相互作用机制 

分 类 号：O657.3[理学—分析化学] O641.3[理学—化学] TS201.2[轻工技术与工程—食品科学]