L-半胱氨酸与牛血清白蛋白相互作用的荧光光谱分析

摘要

The interaction between L-cysteine(L-Cys) and bovine serum albumin(BSA) was investigated by fluorescence quenching spectrum and synchronous fluorescence spectrum.The quenching constant,binding constant,binding sites of L-Cys with BSA,and the thermodynamic parameters (△H,△G,△S)were calculated.The fluorescence of BSA was quenched by L-Cys.The fluorescence peak of BSA shifted from 350 nm to 347.5 nm.Its quenching mechanism was a dynamic process.Their interaction force was hydrophobic force.The synchronous fluorescence spectrum showed that L-Cys influenced the microenvironment around BSA.%运用荧光猝灭光谱、同步荧光光谱探讨了L-半胱氨酸(L-Cys)与牛血清白蛋白(BSA)的相互作用,并计算了猝灭常数、结合常数、结合位点数以及3个热力学参数△H、△G和△S.结果表明,L-Cys使BSA的内源荧光发生猝灭,BSA的发射峰从350 nm蓝移到347.5 nm,荧光猝灭机制为动态猝灭;L-Cys与BSA之间的作用力主要为疏水作用力;L-Cys对BSA结构的微环境有一定的影响.