摘要
运用荧光光谱、紫外吸收光谱、循环伏安法和计算机模拟分子对接技术,研究了2,4,6-三氯苯酚(TCP)与人血清白蛋白(HSA)的相互作用。研究结果表明,TCP与HSA相互结合形成了复合物,且该复合物不具有荧光和电化学活性。TCP通过静态猝灭的方式引起HSA内源荧光的猝灭,并对其构象有一定影响,在温度为300、305、310和315K下,二者的结合常数KA分别为1.702×10~5、3.681×10~6、1.520×10~5和1.335×10~5 L·mol^(–1),平均结合位点数n约为1。TCP在HSA的亚结构域ⅡA中通过疏水和静电共同作用形成稳定的复合物。在研究温度下Hill系数nH值略微大于1,说明TCP间呈现微弱的正协同作用。柠檬酸和维生素C的介入未改变TCP对HSA的猝灭类型,但二者的结合常数和结合位点数急剧降低,严重削弱了TCP与HSA的结合能力。
The interaction between 2,4,6-Trichlorophenol（TCP）and human serum albumin（HSA）was investigated by fluorescence spectroscopy,UV-Vis absorption spectrometry,cyclic voltammetry and molecular docking under simulated physiological conditions.The research showed that the combination of TCP and HSA formed a complex without fluorescence and electrochemical activity.TCP could induced an endogenous fluorescence quenching and had a certain effect on conformation of HSA.The binding constants KAat 300,305,310 and 315 K were 1.702×10^5,3.681×10^6,1.520×10^5 and 1.335×10^5 L·mol^–1 with one binding site,respectively.By analysis of thermodynamic parameters and molecular docking,the hydrophobic and electrostatic forces were the predominant intermolecular force in stabilizing the complex.The primary binding site for TCP was located at sub-domainⅡA of HSA.The values of Hill coefficients were slightly greater than 1,which indicated that there existed the weak positive cooperative effect when TCP bound to HSA.The fluorescence quenching mechanism of HSA did not change in the presence of citric acid and vitamin C,but the binding constants and binding sites of both were drastically reduced,severely weakening the binding ability of TCP and HSA.
作者
霍彩霞
何丽君
杨天宇
HUO Cai-xia;HE Li-jun;YANG Tian-yu(School of Chemistry and Environment Engineering ,Lanzhou City University ,Lanzhou 730070;College of Chemistry and Chemical Engineering, Northwest Normal University ,Lanzhou 730070)
出处
《分析科学学报》
CAS
CSCD
北大核心
2018年第3期357-361,共5页
Journal of Analytical Science
基金
国家自然科学基金(No.21265009)
