谷氨酸对亮蓝与牛血清白蛋白作用机制影响的光谱学研究  

Spectroscopic Study on the Effect of Glutamate on the Interaction Mechanism between Brilliant Blue and Bovine Serum Albumin

作　　者：李纯 王俊茜 赵刚[1] LI Chun;WANG Junqian;ZHAO Gang(College of Chemistry and Materials Engineering,Bohai University,Jinzhou 121013,China)

机构地区：[1]渤海大学化学与材料工程学院,辽宁锦州121013

出　　处：《食品工业科技》2024年第23期20-27,共8页Science and Technology of Food Industry

基　　金：渤海大学博士启动项目(0522bs028-02/05013)。

摘　　要：为了了解谷氨酸(Glu)对食品添加剂亮蓝(BB)与载体蛋白之间结合机制的影响,本文从结合作用力、结合距离、结合位点,以及蛋白质构象变化等方面研究了Glu存在时BB与牛血清白蛋白(BSA)之间的相互作用机制。实验结果表明,BB通过静态猝灭的方式猝灭BSA的内源荧光,但在Glu存在下,BB对BSA的荧光猝灭常数由(8.31±0.52)×10^(4)L·mol^(-1)减小至(5.43±0.04)×10^(4)L·mol^(-1),结合常数由(1.35±0.04)×10^(5)L·mol^(-1)减小至(3.81±0.20)×10^(4)L·mol^(-1)(313 K),即Glu削弱了BB与BSA的结合。此外,Glu还会缩短BB与BSA之间的结合距离(由3.49±0.02 nm变为3.45±0.04 nm),减小BB对BSA二级结构的改变(α-螺旋含量由36.09%±0.01%变为42.14%±0.01%([BSA-Glu]-BB为1:20:1)),即Glu在一定程度上阻止了BB对BSA构象的干扰。To understand the effect of glutamate(Glu)on the binding mechanism between food additive brilliant blue(BB)and the carrier protein,the interaction mechanism between BB and bovine serum albumin(BSA)in the presence of Glu were studied considering binding force,binding distance,binding site,and protein conformational change.The experimental results showed that BB quenched the endogenous fluorescence of BSA via static quenching.However,the fluorescence quenching constant of BB towards BSA decreased from(8.31±0.52)×10^(4) L·mol^(-1) to(5.43±0.04)×10^(4) L·mol^(-1) in the presence of Glu,and the binding constant decreased from(1.35±0.04)×10^(5) L·mol^(-1) to(3.81±0.20)×10^(4) L·mol^(-1)(at 313 K),indicating that Glu weakened the binding of BB to BSA.Additionally,Glu also shortened the binding distance between BB and BSA(from 3.49±0.02 nm to 3.45±0.04 nm)and reduced the alteration of BSA's secondary structure by BB(theα-helix content changed from 36.09%±0.01%to 42.14%±0.01%(when the[BSA-Glu]-BB was 1:20:1)),indicating that Glu partially prevented the conformational disturbance of BSA by BB.

关 键 词：亮蓝 牛血清白蛋白 谷氨酸 作用机制 

分 类 号：O657[理学—分析化学]