Characterization of the interaction between human serum albumin and morin.
Characterization of the interaction between human serum albumin and morin.
复制标题
DOI：
10.1016/j.bbagen.2006.03.026
复制
发表时间：
2006-08
期刊：
影响因子：
--
通讯作者：
M. Xie;M. Long;Yuan-xia Liu;Chuan Qin;Ying-Dian Wang
中科院分区：
文献类型：
--
作者：
M. Xie;M. Long;Yuan-xia Liu;Chuan Qin;Ying-Dian Wang
首次用荧光光谱、紫外吸收光谱和傅立叶变换红外光谱研究了桑色素与人血清白蛋白的相互作用。荧光数据显示，在HSA上存在桑色素的特异性结合位点，在生理条件下结合亲和力为1.13±0.11×10−5L Mol− 1。由于激发态质子转移，桑色素的内源荧光在HSA存在下显著增强。在pH值为6.4 ~ 8.4的缓冲液中，桑色素与蛋白质的结合能力随pH值的增加而降低，表明羟基质子化程度在药物与蛋白质的结合过程中起重要作用。根据桑色素在不同pH介质中的紫外吸收光谱，对药物分子上羟基的解离行为进行了归属。利用桑色素与人血清白蛋白相互作用后的二阶导数紫外吸收光谱研究了桑色素与蛋白质的结合方式。桑色素与人血清白蛋白结合后，其紫外吸收带I明显红移，进一步证实了人血清白蛋白-桑色素复合物的形成，并利用这一性质估算了结合常数。桑色素与人血清白蛋白的相互作用导致蛋白质的α-螺旋和β-折叠结构明显减少。
The interaction of morin with human serum albumin (HSA) has been investigated by using fluorescence, UV absorption and Fourier transform infrared spectroscopic approaches for the first time. Fluorescence data revealed the presence of a specific binding site on HSA for morin, and the binding affinity was 1.13±0.11×10−5L Mol−1in the physiological condition. The intrinsic fluorescence of morin was conspicuously enhanced in the presence of HSA due to excited-state proton transfer. The binding ability of morin to protein decreased with the increase of the buffer pH from 6.4 to 8.4, which signified that the level of protonation of the hydroxyl groups played an important role during the drug–protein binding process. From the UV absorption spectra of morin in various pH medium, the dissociation behaviors of the hydroxyl groups on the drug molecule were assigned. The second derivative UV absorption spectra of morin after interacting with HSA were used to elucidate the binding mode of morin to protein. The obvious red shift of the UV absorption band I of morin upon binding to HSA further confirmed the formation of HSA–morin complex, and this property was also utilized to estimate the binding constant. The interaction between morin and HSA induced an obvious reduction of the protein α-helix and β-sheet structures.