光谱法研究2-乙基-3-甲基-吡嗪与牛血清白蛋白的相互作用

Spectroscopic Study on the Interaction of a Novel 2-Ethyl-3-methylpyrazine(NEMP)and Bovine Serum Albumin

利用荧光和紫外光谱法在模拟生理条件下,研究了牛血清白蛋白(BSA)和2-乙基-3-甲基-吡嗪(NEMP)的相互作用。应用Stern-Volmer方程、Lineweaver-Burk双倒数方程及F?rster非辐射能量转移理论,计算获得3个不同温度下(288、298、308 K)两者的猝灭常数(K_(SV))、结合常数(K_(q))、结合距离(r)和热力学参数(ΔH,ΔG和ΔS)等。结果显示:在不同温度下,BSA和NEMP均能相互结合生成新的复合物,且属于静态猝灭;结合距离小于7 nm;同步荧光显示NEMP对BSA的构象产生影响,主要是对其中酪氨酸残基有显著的影响;而在紫外光谱中BSA的最大吸收峰向较短波长偏移,BSA与NEMP之间形成了基态配合物。

The interaction mechanism of bovine serum albumin(BSA)with 2-ethyl-3-methylpyrazine(NEMP)at three different temperatures was studied in Tris-HCl buffer solution at p H7.43.Refering to Förster non-radioactive energy transfer theory,the Stern-Volmer quenching constant(K_(SV)),the bimolecular quenching rate constant(K_(q)),binding distance(r)and the thermodynamic parameters(ΔH,ΔG andΔS)between NEMP and BSA were measured.The results showed that BSA and NENP could form new complexes at three temperatures with static quenching mechanism.The binding distance was less than 7 nm.Synchronous fluorescence spectra showed that NEMP had an effect on the conformation of BSA,mainly on the Tyr residues.The maximum absorption peak of BSA in the ultraviolet absorption spectrum was shifted,and the ground state complex was formed between BSA and NEMP.