光谱法研究牛血清白蛋白与磷钼酸的相互作用  

Spectroscopic Studies of Interaction between Bovine Serum Albumin and Phosphomolybdic Acid

作　　者：张海蓉[1] 边贺东[1] 于青[1] 梁宏[2] 

机构地区：[1]广西师范大学化学化工学院 [2]药用资源化学与药物分子工程教育部重点实验室,广西师范大学,桂林541004

出　　处：《化学通报》2010年第7期628-633,共6页Chemistry

基　　金：国家自然科学基金(20671023,30460153);广西自然科学基金;广西高校自然科学基金;教育部重点项目基金(03101,204111);药用资源化学与药物分子工程教育部重点实验室资助

摘　　要：运用UV-Vis光谱、荧光光谱、同步荧光光谱、FT-IR光谱等手段,研究了在模拟人体生理条件下,牛血清白蛋白(BSA)与磷钼酸的相互作用。UV-Vis光谱显示,加入磷钼酸后,BSA的紫外吸收降低且吸收峰红移,表明磷钼酸与BSA形成了复合物;荧光猝灭光谱显示磷钼酸对BSA有荧光猝灭作用,且其荧光猝灭机理符合静态机制,磷钼酸与BSA结合的结合常数为:Ks=2.539×104L·mol-1;探针实验表明磷钼酸与BSA在结合位点I发生结合;Fster偶极-偶极非辐射能量转移机理确定了磷钼酸在BSA中与第214位色氨酸残基之间的距离r=1.93nm;FT-IR光谱显示磷钼酸诱导BSA的二级结构发生了变化,α-螺旋含量降低。The interaction between bovine serum albumin （BSA） and phosphomolybdic acid （PMA） at physiological condition was investigated by spectroscopies of ultraviolet-visible,fluorescence,synchronous fluorescence and FT-IR.The UV absorbance of BSA decreased and the peaks had red-shift after adding PMA,which indicated that there was a complex formed.The fluorescence quenching spectra indicated that PMA can quench the fluorescence of BSA with the quenching mechanism.The binding constant （Ks） of BSA and PMA was 2.539 × 104 L·mol-1.The displacement experiment showed that PMA can bind to the site I.The distance between the 214 tryptophan residues in BSA and PMA was estimated to be 1.93nm using Fster＇s equation on the basis of fluorescence energy transfer.FT-IR experiments showed that the secondary structure of BSA is changed while adding PMA and the α-helical content of BSA was reduced.

关 键 词：磷钼酸 牛血清白蛋白 荧光光谱 傅立叶红外光谱 紫外-可见吸收光谱 

分 类 号：R96[医药卫生—药理学]