光谱法研究三磷酸腺苷二钠与牛血清白蛋白的相互作用及共存金属离子的影响

Study on the interaction and between adenosine disodium triphosphate with bovine serum albumin and the effect of coexistent metal ions on the reaction by spectroscopic methods

在模拟人体生理条件下,用紫外-可见吸收光谱法和荧光光谱法研究三磷酸腺苷二钠(ADT)和牛血清白蛋白(BSA)的相互作用及共存金属离子Mn^(^(2+)),Co^(2+),Cr^(3+),Mg^(2+),Fe^(3+)对两者结合作用的影响.结果表明:ADT对BSA的荧光有猝灭作用,其猝灭过程属于动态猝灭.通过计算得出ADT与BSA的结合常数Kb及结合为点数n.根据热力学参数确定了ADT和BSA之间的作用力类型主要为静电引力.ADT在BSA中的结合位点主要位于亚螺旋域ⅡA.Hill系数nHill≈1,表明ADT对两者的结合几乎无协同作用.用同步荧光光谱法研究了ADT对BSA构象的影响.此外还详细探讨了共存金属离子对ADT与BSA结合作用的影响.

Under the simulation of the human body physiological conditions, the interaction between Adenosine Disodium Triphosphate （ADT） and bovine serum albumin （BSA） was studied with UV- visible absorption spectra and fluorescence spectra. The effects of metal ions Mn2＋ , Co2＋ , Cr3 ＋ , Mg2＋ , Fe3＋ on the interaction of ADT with BSA were also discussed. The results showed that the fluorescence of BSA is quenched by ADT, which is a dynamic quenching process. The binding constants Kb and the corresponding number of binding sites n are obtained by calculation. The thermodynamic parameters obtained from measured data showed that the interaction of ADT and BSA is mainly driven by the electrostatic force. The primary binding site for ADT is located at sub-domain HA of BSA. The values of Hillg coefficients were nearly 1 ,which indicate that there is nearly no cooperative effect. The effect of ADT on the conformation of BSA is analyzed by synchronous fluorescence spectrometry. In addition, the effect of metal ions on the binding constant of ADT with BSA is also studied.