论文部分内容阅读
目的研究血清白蛋白(serum albumin,SA)结合松果菊苷(echinacoside,ECH)的分子作用机制。方法生理条件下,光谱法测定药物与蛋白质的结合参数,分子模拟构建ECH与牛血清白蛋白(bovine serum albumin,BSA)的结合模型,考察药物与SA结合机制。结果构建的药物与BSA结合模型表明,药物与蛋白质的相互作用力主要是氢键和范德华力,兼有疏水作用力。光谱实验表明ECH与BSA的相互作用为静态结合过程,结合强度较强,ECH与BSA分子的结合距离(r)值较小,说明发生了能量转移现象。ECH对BSA的结构域微区构象产生影响,使结合位域的疏水性发生改变。分析荧光相图得出ECH与BSA反应构象型态的变迁为“二态”模型。BSA与ECH相互作用的热力学参数表明ECH与BSA之间是以氢键和范德华力为主的分子间作用。荧光偏振定量证明了BSA与ECH相互作用过程中生成了非共价复合物。结论光谱实验与计算机模拟结果一致,可为研究ECH与BSA相互作用机制提供一定的参考。
Objective To study the molecular mechanism of serum albumin (SA) combined with echinacoside (ECH). Methods Under physiological conditions, the binding parameters of drugs and proteins were determined by spectrometry, and the binding model between ECH and bovine serum albumin (BSA) was constructed by molecular simulation to investigate the mechanism of drug binding to SA. Results The results showed that the interaction between drug and protein was mainly hydrogen bond and Van der Waal's force, both hydrophobic and hydrophobic. Spectral experiments show that the interaction between ECH and BSA is a static binding process, the binding strength is strong, and the binding distance (r) value between ECH and BSA molecules is small, indicating that energy transfer occurs. ECH affects the domain domain conformation of BSA and changes the hydrophobicity of the binding domain. The fluorescence phase diagram was analyzed to show that the change in the conformational shape of the reaction between ECH and BSA is a “binary state” model. The thermodynamic parameters of the interaction between BSA and ECH indicate that the intermolecular interaction between ECH and BSA is dominated by hydrogen bonding and van der Waals forces. Fluorescence polarization quantification demonstrated the formation of non-covalent complexes during the interaction of BSA with ECH. Conclusions The results of spectral experiments are in good agreement with those of computer simulations, and provide some references for studying the interaction mechanism between ECH and BSA.