光谱法与分子模拟技术研究丽春红2R与牛血清蛋白的相互作用

Study on Interaction between Ponceau 2R and Bovine Serum Albumin by Spectroscopy and Molecular Modeling

采用荧光光谱、同步荧光光谱、紫外-可见吸收光谱及分子模拟技术研究了模拟生理条件下丽春红2R(P2R)与牛血清白蛋白(BSA)的相互作用。实验结果表明,P2R-BSA体系的荧光猝灭机制为内源荧光猝灭,猝灭原因为静态猝灭和非辐射能量转移;计算了不同温度下体系的结合常数Ka及结合位点数n;根据热力学参数推断出作用力类型;求出室温下荧光给体-受体间的结合距离;同步荧光法证实丽春红2R对BSA构象未产生影响;分子模拟研究结果表明二者间的主要作用力为氢键和疏水作用力。

The interaction between ponceau 2R （P2R） and bovine Serum albumin （BSA） and their interaction mechanism were investigated by fluorescence spectroscopy, synchronous fluorescence spectroscopy, UV absorption spectroscopy and molecular modeling under the simulated physiological condition. The results showed that the intrinsic fluorescence of BSA was quenched by P2R, the quenching reasons were both static quenching and non-radiation energy transfer. Binding constant （K_a） and binding sites （n） at different temperatures were calculated. The results of corresponding thermodynamic parameters as well as binding distance between BSA and P2R were obtained. The synchronous fluorescence spectrometry revealed that P2R had no impact on the conformation of BSA. The result of molecular modeling indicated that P2R can bind with BSA with hydrophobic force and hydrogen bonding as the main acting force.