水溶性阳离子型吡啶基咔咯镓配合物与人血清蛋白的相互作用

Interaction of Human Serum Albumin and Water Soluble Cationic Pyridyl Corrole Gallium Complex

利用紫外吸收光谱、荧光光谱、圆二色(CD)光谱和分子对接计算探究了5,10,15-三[4-(N-甲基-吡啶)]咔咯镓配合物(1-Ga)与人血清蛋白(HSA)的相互作用.结果表明,HSA的荧光能被1-Ga静态猝灭,两者的结合常数为2.82×104L/mol,作用距离为3.342 nm.热力学参数显示1-Ga主要通过氢键和疏水作用与HSA结合,位点标记竞争实验表明1-Ga优先结合HSA的布洛芬位点Ⅱ.此外,紫外吸收光谱和CD光谱显示二者的相互作用会导致HSAα-螺旋结构的减少.分子对接计算结果表明1-Ga优先结合在HSA亚结构域ⅢA的位点Ⅱ疏水袋中.

The interaction between gallium 5, 10, 15-tris （4-methylpyridiniumyl） corrole （1-Ga） and human serum albumin（HSA） was investigated using UV-Vis spectra, fluorescence spectra, circular dichroism（CD） spectra and molecular docking simulation. The results reveal that the fluorescence quenching of HSA by 1-Ga is a static quenching process. The binding constant of complex 1-Ga with HSA is 2.82×104 L/mol, and bin- ding distance r=3. 342 nm. Thermodynamic parameters show the interaction is mainly driven by hydrophobic and hydrogen binding forces. Site marker competition experiment indicates 1-Ga preferably bind to ibuprofen site Ⅱ of HSA. Also, a-helix content of HSA will decrease upon binding 1-Ga as indicated by UV-Vis and CD spectroscopy. Molecular docking simulation confirmed 1-Ga bind to the hydrophobic pocket site Ⅱ in domain ⅢA of HSA.