论文部分内容阅读
目的:运用荧光光谱(FS)结合衰减全反射傅里叶变换红外光谱研究了6种胆酸类(CAs)小分子与牛血清白蛋白(BSA)的相互作用。方法:在pH 7.40和离子强度0.15 mol·L-1的模拟生理条件下,根据Stern-Volmer方程、Lineweaver-Burk双倒数方程、双对数方程、热力学公式、同步荧光及衰减全反射傅里叶变换红外光谱求出CAs与BSA相互作用的猝灭常数、结合常数K LB、结合位点数n、结合力类型及BSA构象变化情况。结果:6种胆酸类小分子对BSA的猝灭属于静态猝灭,结合位点约为0.5∶1,结合力主要为氢键或Vander Walls力,对牛血清白蛋白构象影响较小。结论:胆酸类小分子与牛血清白蛋白之间具有一定的结合作用,这为胆酸类小分子在体内被蛋白质储存和转运提供了条件;同时阐明了胆酸类小分子与牛血清白蛋白相互作用的机制,为进一步探讨胆酸类小分子在生物体内与蛋白质的作用机制和生物学效应提供了理论依据。
OBJECTIVE: To study the interaction between six kinds of small cholic acids (CAs) and bovine serum albumin (BSA) by fluorescence spectroscopy (FS) combined with attenuated total reflectance Fourier transform infrared spectroscopy. Methods: Under the simulated physiological conditions of pH 7.40 and ionic strength of 0.15 mol·L-1, the double-reciprocal equation of Lineweaver-Burk, the double logarithm equation, the thermodynamic formula, the synchronous fluorescence and the attenuated total reflection Fourier The quenching constants, the binding constants K LB, the number of binding sites n, the type of binding force and the conformational changes of BSA were calculated by the transformation infrared spectroscopy. Results: The quenching of BSA by six cholic acid small molecules belongs to the static quenching. The binding site is about 0.5:1. The binding force is mainly hydrogen bond or Vander Walls force, which has little effect on the conformation of bovine serum albumin. Conclusion: There is a certain binding between cholic acid small molecules and bovine serum albumin, which provides the conditions for cholic acid small molecules to be stored and transported in vivo. At the same time, elucidation of the relationship between bile acid small molecules and bovine serum albumin The mechanism of protein interaction provides a theoretical basis for further exploring the mechanism and biological effect of cholic acid small molecules in vivo and protein.