利福平和牛血清白蛋白相互结合作用的荧光光度特性

Fluorospectrophotometric Characteristic of the Intercombination of Rifampin with Bovine Serum Albumin

摘要: 应用荧光光度法研究了水溶液中利福平与牛血清白蛋白分子间的结合反应,讨论了利福平对蛋白质内源荧光的猝灭机理,测定了结合常数(KA=3.1×10-5L·mol-1)和结合位点数(n=1.06).依据Frster非辐射能量转移理论确定了供体-受体间的结合距离(r=3.89 nm)和能量转移效率,并用同步荧光技术考察了利福平对牛血清白蛋白构象的影响.

Abstract: Intermolecular combination of rifampin with bovine serum albumin (BSA) in aqueous solution was studied by fluorospectrophotometry. Mechanism of quenching of fluorescence of BSA by rifampin was discussed. Equilibrium constant of combination (KA) and number of combination site (n) were determined and values obtained were 3.1×10-5L·mol-1 and 1.06 respectively. By the Frster non-radiating energy transfer theory,the combination distance between the donor and acceptor as well as the efficiency of energy transfer were determined,and the value of combination distance (r) was found to be 3.89 nm. Effect of rifampin on the configuration of BSA was studied by the synchronous fluorospectrophotometry.