光谱探针猩红S与牛血清白蛋白结合的发光光谱(英文)  

Luminescence Spectroscopy of Conjugation Reaction between Bovine Serum Albumin and Spectroscopic Probe Ponceau S

作　　者：刘保生[1] 薛春丽[1] 王晶[1] 杨超[1] 吕运开[1] 

机构地区：[1]河北大学理化分析中心药物化学与分子诊断教育部重点实验室,河北保定071002

出　　处：《发光学报》2011年第1期100-107,共8页Chinese Journal of Luminescence

基　　金：Project supported by National Science Foundation of China(20675024)~~

摘　　要：利用荧光光谱和紫外吸收光谱,详细研究了不同温度下猩红S(PS)与牛血清白蛋白(BSA)的结合反应,发现PS对BSA的内源性荧光具有较强的猝灭作用,其猝灭机理属于静态猝灭,由此求得PS与BSA间的结合常数、结合位点数及热力学参数等。结果表明:PS与BSA之间形成了1:1稳定复合物,它们之间的作用力主要是静电引力。根据Frster非辐射能量转移理论,确定了PS与BSA之间的结合距离r<7nm。同步荧光光谱研究表明:PS对BSA构象发生了影响,使BSA酪氨酸残基所处环境的极性减弱疏水性增强而色氨酸残基不受影响。利用对血清蛋白具有特异性结合的竞争试剂确定了PS在BSA的键合位点为IIA亚区的siteI,证明PS与BSA也存在特异性结合,PS可以用作新的位置探针替代竞争试剂来研究小分子与蛋白的结合位置。Ponceau S（PS） can quench the fluorescence of bovine serum albumin（BSA） in the aqueous solution of pH=7.40.The static fluorescence quenching process between BSA and PS was confirmed and the binding constant,the number of binding sites and thermodynamic parameters between BSA and PS were obtained.It showed that the number of binding sites was 1 and the electrostatic attraction played an important role in the binding of BSA to PS.Based on the theory of Frester energy transfer,the binding distance（r〈7.0 nm） between PS and BSA was obtained.Studies utilizing synchronous spectra showed that the conjugation reaction between PS and BSA would affect the conformation of BSA,leading to the weak polarity around tyrosine residues and the strong hydrophobicity.The site markers competitive experiments indicated that the binding of PS to BSA primarily took place in sub-domain ⅡA（site Ⅰ）.

关 键 词：牛血清白蛋白 猩红S 结合反应 键合位点 光谱探针 

分 类 号：O482.31[理学—固体物理] O657.3[理学—物理]