硝酰基荧光探针与牛血清白蛋白相互作用的研究

Investigation of Interaction Between a Fluorescent Probe for HNO and Bovine Serum Albumin

在模拟生理条件下,用光谱法研究了硝酰基(HNO)探针(4-[2-(diphenylphosphino)benzoate]-N-butyl-1,8-naphtalimide,NIM)与牛血清白蛋白(BSA)的相互作用。结果表明,探针与BSA之间主要是静态猝灭方式。药物代替实验表明,探针与BSA的色氨酸残基相结合。由热力学数据确定了二者之间的作用力类型为静电引力。二者之间的结合距离为3.73nm。利用同步荧光、CD光谱、红外光谱以及三维荧光光谱考察了探针对BSA构象的影响。

The binding of 4-[2-（diphenylphosphino）benzoate]-N-butyl-1,8-naphtalimide（NIM）with bovine serum albumin（BSA）in physiological buffer（pH=7.40）was investigated by the multispectroscopic technique.Spectroscopic analysis revealed that the quenching mechanism between NIM and BSA was static quenching.The displacement experiments showed that NIM bound to tryptophan residues on BSA.The calculated thermodynamic parameters revealed that the binding of NIM-BSA was relied on electrostatic interaction.The binding distance of NIM with BSA was calculated to be 3.73 nm.The results of synchronous fluorescence,CD,FT-IR and three-dimensional fluorescence spectra demonstrated that the conformation of BSA was changed by the binding of NIM.