论文部分内容阅读
利用紫外光谱、荧光光谱、红边激发荧光位移(REES)法、圆二色谱(CD)结合分子模拟技术共同研究了模拟生理条件下杨梅素与牛血清白蛋白(BSA)的相互作用,阐述了相互作用机制.分子模拟结果表明,杨梅素与蛋白在亚结构域II A的疏水腔内结合,主要作用力为疏水作用力和氢键.依据荧光猝灭法判断猝灭机制为静态猝灭,并得到不同温度下药物与蛋白相互作用的结合常数(Ka)及结合位点数(n),根据热力学参数判断出作用力类型,并且计算出杨梅素与蛋白的结合距离,与分子模拟得到的判定结果基本一致.通过紫外光谱、同步荧光光谱以及REES法获得的信息讨论了相互作用时BSA中色氨酸(Trp)微环境的变化;并利用CD谱的测定结果定量计算了BSA二级结构中α-螺旋含量的变化.
The interaction between myricetin and bovine serum albumin (BSA) under simulated physiological conditions was studied by ultraviolet spectroscopy, fluorescence spectroscopy, red edge excited fluorescence shift (REES) and circular dichroism (CD) Interaction mechanism.The molecular simulation results show that myricetin binds with the protein in the hydrophobic cavity of subdomain II A. The main force is hydrophobic interaction and hydrogen bond.The quenching mechanism is quenched by fluorescence quenching, The binding constants (Ka) and the number of binding sites (n) of drug-protein interactions at different temperatures were obtained. The type of force was determined according to the thermodynamic parameters, and the binding distance between myricetin and protein was calculated. The results were basically the same. The changes of tryptophan (Trp) microenvironment in BSA at the interaction were discussed by the information obtained by UV spectroscopy, synchronous fluorescence spectroscopy and REES method. The CD spectra were used to quantitatively calculate the changes of the microenvironment of BSA in secondary structure of BSA Changes in alpha-helical content.