大黄酸铜(Ⅱ)配合物与血清白蛋白的相互作用

采用荧光光谱法和紫外光谱法研究了大黄酸铜配合物与牛血清白蛋白之间的相互作用.大黄酸铜配合物能显著猝灭牛血清白蛋白的内源荧光并以静态猝灭为主；计算了298 K和309 K温度下结合常数、结合位点，根据热力学参数判断大黄酸铜配合物与牛血清白蛋白之间具有较强的疏水作用力；依据F?rster的偶极-偶极非辐射能量转移理论,计算出大黄酸铜在蛋白质中结合位置与色氨酸残基间的距离为3.21 nm, 表明大黄酸铜的部分片段能够插入蛋白质分子内部；用同步荧光光谱和圆二色光谱技术探讨了大黄酸铜对牛血清白蛋白构象的影响.

Interaction of Rhein-Cu(Ⅱ) Complexes with Bovine Serum Albumin

The interaction between rhein-Cu and bovine serum albumin(BSA) was investigated by fluorescence and ultraviolet spectroscopy. The results indicated that rhein-Cu led to the intrinsic fluorescence quenching of BSA through a static quenching procedure. The binding constants KA and binding site n at 298 K and 309 K were obtained. The binding locality was found to be an area 3.24 nm away from tryptophan residue in BSA based on F?rster non-radiation energy transfer mechanism. The experimental results showed that the rhein-Cu could be inserted into the BSA, quenching the inner fluorescence by forming the rhein-Cu-BSA complex. The binding power between rhein-Cu and BSA is mainly the hydrophobic interaction according to the thermodynamic parameters. The effect of rhein-Cu on the conformation of BSA was analyzed by circular dichroism(CD) and synchronous fluorescence spectra.