光谱法研究牡荆素与蛋白质相互作用及共存金属离子的影响

Studies on interaction of vitexin with bovine serum albumin and effect of the coexistent metal ions on the reaction by spectrometry

利用荧光光谱法和紫外-可见光谱法研究了牡荆素(VT)与牛血清白蛋白(BSA)之间的相互作用。VT对BSA的荧光猝灭为动态猝灭过程,测定了不同温度下的猝灭常数;根据F rster非辐射能量转移理论,计算出VT在BSA中的结合位置与色氨酸残基间的距离为2.675 nm;通过热力学参数推断出VT与BSA之间主要靠疏水作用力结合;探讨了共存金属离子对VT与BSA相互作用的影响。

The interaction between vitexin and bovine serum albumin（BSA） was studied by fluorescence and UV/Vis absorption spectroscopy.The results revealed that vitexin caused the fluorescence quenching of BSA through a dynamic quenching procedure.The quenching constant was obtained at various temperatures.The binding locality was found to be an area 2.675 nm away from tryptophan residue in BSA based on Frster＇s non-radiation energy transfer mechanism.The binding power between vitexin and BSA is mainly the hydrophobic interaction according to the thermodynamic parameters.The effect of coexistent metal ions on the reaction of vitexin to BSA was also discussed.