【摘要】 目的研究中药活性成分腺苷(adenosine,Ade)与人血清白蛋白(human serum albumin,HSA)的结合反应机制。方法利用荧光光谱及紫外吸收光谱实验测定了反应体系的结合常数K、结合位点数n,探讨了反应机制;依据Fōrster理论测定了反应体系的能量转移参数并考察了腺苷对人血清白蛋白构象的影响;分子模建腺苷与人血清白蛋白的结合反应模型并与实验结果进行了比较。结果腺苷与人血清白蛋白结合生成静态复合物,结合常数K=1.39×103L.mol-1,结合位点n=0.94;腺苷与人血清白蛋白的结合距离r很小,说明发生了能量转移现象;腺苷改变了人血清白蛋白结合位域的疏水性并造成微区构象发生变化。计算机模拟结果显示,腺苷与人血清白蛋白的相互作用主要为腺苷的嘌呤环与人血清白蛋白分子中氨基酸残基的疏水作用和氢键。结论理论计算与实验测试获得了一致性结果,此为中药活性成分腺苷的药理作用机制研究提供一定参考。更多还原

【Abstract】 OBJECTIVE To study the binding mechanism between adenosine(Ade),an active component of some traditional Chinese medicines,and human serum albumin(HSA).METHODS The binding constant K and binding sites n were obtained by using fluorescence and UV absorption spectroscopy.In addition,the reaction mechanism was discussed.The energy transfer parameters of the reaction system were determined as was the effect of Ade on HSA′s conformation on the basis of Fōrster theory.The binding reaction model of HSA with Ade was constructed through molecular simulation and compared with the experiment results.RESULTS Ade could bind HSA to form static complex.The binding constant(K) was 1.39×103 L·mol-1 and binding sites(n) was 0.94.The binding distance r between Ade and HSA was very short,which indicated the phenomenon of energy transfer.Ade changed the hydrophobic environment of the binding domain in HSA and caused certain changes for micro area conformation.Computer molecular docking technology showed that the interactions of Ade with HSA were mainly hydrophobic interaction and hydrogen bonding between purine ring of Ade and amino acid residues of HSA.CONCLUSION The theoretical calculation and experiment results were in consistency,which provided certain reference for the study of pharmacological mechanism for the active ingredient of some traditional Chinese medicines,adenosine.更多还原