College of Chemical and Pharmaceutical Engineering, Jingchu University of Technology, Jingmen, 448000 Hubei, People's Republic of China.
Mol Biol Rep. 2012 Jul;39(7):7457-63. doi: 10.1007/s11033-012-1578-z. Epub 2012 Feb 9.
A coordination compound of 5, 7-dihydrox-4'-methoxyisoflavone and selenium was synthesized and its structure was identified by IR, LC-MS and (1)H-NMR. Its biochemical effects were investigated using bovine serum albumin (BSA) as a target protein molecule, in which process three-dimensional (3D) fluorescence spectra, ultraviolet spectra, circular dichroism (CD) spectra and fluorescence probe techniques were employed. The interaction of SEIF and BSA was discussed by fluorescence quenching method and Förster non-radiation energy transfer theory. The thermodynamic parameters ΔH (θ), ΔG (θ), ΔS (θ) at different temperatures were calculated according to Van't Hoff isobaric equation and the results indicated the interaction was an exothermic as well as a spontaneous process. The binding site was explored by fluorescence probe method using warfarin and ibuprofen as markers. Intramolecular forces which are responsible for maintaining the binding were mainly hydrogen bond and van der Waals power. The average distance from the tryptophan residue in domain II of BSA (donor) to SEIF (acceptor) is 3.57 nm at body temperature. The conformation changes of BSA were investigated by 3D fluorescence and CD spectra.
合成了 5,7-二羟基-4'-甲氧基异黄酮和硒的配位化合物，并通过红外光谱（IR）、液质联用（LC-MS）和（1）H-NMR 对其结构进行了鉴定。以牛血清白蛋白（BSA）为靶蛋白分子，采用三维（3D）荧光光谱、紫外光谱、圆二色（CD）光谱和荧光探针技术研究了其生化效应。利用荧光猝灭法和福斯特非辐射能量转移理论探讨了 SEIF 与 BSA 的相互作用。根据范特霍夫等压方程，计算了不同温度下的热力学参数ΔH（θ）、ΔG（θ）和ΔS（θ），结果表明该相互作用是放热的自发过程。采用华法林和布洛芬作为标记物，通过荧光探针法研究了结合部位。负责维持结合的分子间力主要是氢键和范德华力。在体温下，BSA 中结构域 II 中的色氨酸残基（供体）到 SEIF（受体）的平均距离为 3.57nm。通过 3D 荧光和 CD 光谱研究了 BSA 的构象变化。
