盐酸拓扑替康与人血清白蛋白的相互作用及分子模拟

用荧光光谱法、分光光度法研究了盐酸拓扑替康(topotecan hydrochloride, 简记为THC)与人血清白蛋白(human serum albumins, HSA)的相互结合反应. 计算了反应的结合常数、结合位点数和热力学常数. 盐酸拓扑替康在人血清白蛋白上的结合位置与色氨酸残基间的距离为3.63 nm. 分子模型研究表明, 盐酸拓扑替康与人血清白蛋白的亚结构域IIA结合, 二者间的作用力主要为疏水作用, 此外, 蛋白质的丙氨酸(Ala-291)残基和天冬氨酸(Asp-256)残基与盐酸拓扑替康之间还存在氢键作用力.

Molecular Simulation and Interaction between Human Serum Albumin and Topotecan Hydrochloride

The binding reaction between topotecan hydrochloride(THC) and human serum albumin(HSA) was studied by fluorescence and UV-Vis absorption spectra.The binding equilibrium constant,number of binding site and thermodynamic parameters were calculated.The distance between the binding site and tryptophan residue is 3.63 nm.The study of molecular simulation indicated that topotecan hydrochloride bound within the subdomain IIA of human serum albumins and the interaction between topotecan hydrochloride and HSA was dominated by hydrophobic force.In addition,both the residues Ala-291 and Asp-256 of HSA formed hydrogen bonds with topotecan hydrochloride,respectively.