Wu Di, Yan Jin, Wang Jing, Wang Qing, Li Hui
College of Chemical Engineering, Sichuan University, Chengdu 610065, China.
College of Chemical Engineering, Sichuan University, Chengdu 610065, China.
Food Chem. 2015 Mar 1;170:423-9. doi: 10.1016/j.foodchem.2014.08.088. Epub 2014 Aug 28.
Binding interaction of human serum albumin (HSA) with allura red AC, a food colourant, was investigated at the molecular level through fluorescence, ultraviolet-visible, circular dichroism (CD) and Raman spectroscopies, as well as protein-ligand docking studies to better understand the chemical absorption, distribution and transportation of colourants. Results show that allura red AC has the ability to quench the intrinsic fluorescence of HSA through static quenching. The negative values of the thermodynamic parameters ΔG, ΔH, and ΔS indicated that hydrogen bond and van der Waals forces are dominant in the binding between the food colourant and HSA. The CD and Raman spectra showed that the binding of allura red AC to HSA induces the rearrangement of the carbonyl hydrogen-bonding network of polypeptides, which changes the HSA secondary structure. This colourant is bound to HSA in site I, and the binding mode was further analysed with the use of the CDOCKER algorithm in Discovery Studio.
通过荧光光谱、紫外可见光谱、圆二色光谱（CD）和拉曼光谱以及蛋白质-配体对接研究，在分子水平上研究了人血清白蛋白（HSA）与食用色素诱惑红AC的结合相互作用，以更好地理解色素的化学吸收、分布和运输。结果表明，诱惑红AC能够通过静态猝灭淬灭HSA的固有荧光。热力学参数ΔG、ΔH和ΔS的负值表明，氢键和范德华力在食用色素与HSA的结合中起主导作用。CD和拉曼光谱表明，诱惑红AC与HSA的结合诱导了多肽羰基氢键网络的重排，从而改变了HSA的二级结构。这种色素在位点I与HSA结合，并使用Discovery Studio中的CDOCKER算法进一步分析了结合模式。
