两种金属卟啉与牛血清白蛋白作用的研究

采用荧光光谱法和紫外-可见吸收光谱法研究了两种金属卟啉与牛血清白蛋白(BSA)的结合作用。实验结果表明:卟啉配合物对BSA有较强的荧光猝灭作用,按照Stern-Volmer方程和Lineweaver-Burk双倒数方程分析和处理试验数据,得到反应的结合常数、结合位点数和热力学参数等;探讨了金属卟啉的分子结构对结合反应的影响。利用同步荧光技术考察了金属卟啉对BSA构象的影响,发现金属卟啉的加入使BSA构象发生变化,色氨酸残基所处环境的疏水性降低。

Study on the Interaction Between Metalloporphyrins and BSA

The binding reaction between two metalloporphyrins and bovine serum albumin(BSA) was investigated by fluorescence and UV-vis absorption spectroscopy.The experimental results showed that the fluorescence intensity of BSA at 342 nm was quenched when metalloporphyrin was added.The fluorescence quenching data was analyzed according to Stem-Volmer equation and double-reciprocal equation,and the binding site number n,apparent binding constant K and thermodynamic parameters were obtained.The effect of molecular structure of metalloporphyrin on mechanism of binding reaction was discussed.Using the synchronous fluorescence spectropcopy,the effect of metalloporphyrin on the conformation of BSA was studied.The results indicated that the conformation of BSA was changed when metalloporphyrin was added,and the hydrophobic properties of the environment of tryptophan decreased.