Fe离子不同形态诱导血清蛋白质分子别构效应的比较分析研究  

Comparison of the allosteric effects of serum protein molecules induced by different shaped Fe ion

作　　者：郭明[1] 李慧东[1] 张璐颖[1] 周珊[1] 

机构地区：[1]浙江农林大学化学系,浙江临安311300

出　　处：《分子科学学报》2013年第1期31-36,共6页Journal of Molecular Science

基　　金：国家自然科学基金资助项目(20877072)资助;浙江省科技厅资助项目(2010C33070)资助

摘　　要：通过紫外差谱方法研究金属Fe离子不同形态与不同类别血清白蛋白分子的别构效应,并比较分析分子作用机理.考察氧介导条件对Fe离子不同形态分别与人血清白蛋白(Human serum albumin,HSA)、牛血清白蛋白(Bovine serum albumin,BSA)别构效应的影响,建立定量模型方程.结果表明,Fe离子不同形态与血清白蛋白结合反应体系中存在Fe(Ⅱ)-HSA/BSA～Fe(Ⅲ)-HSA/BSA的动态平衡,Fe(Ⅱ)-HSA/BSA～Fe(Ⅲ)-HSA/BSA电子转移效应是别构效应的关键影响因素,导致Fe离子不同形态与血清白蛋白结合反应的别构效应迥异,呈现形态显著性差异.氧介导及无氧条件下的Fe(Ⅱ)-HSA/BSA～Fe(Ⅲ)-HSA/BSA电子转移效应机理不同.无氧条件下,Fe(Ⅲ)与血清白蛋白的相互作用遵循动力学一级反应规律,计算得到结合反应体系的速率常数k及自由能变ΔG≠.The allosterie effects of different shaped Fe ion interacted respectively with different categories of serum albumin were investigated and compared by using the UV difference spectrum method, and molecular mechanism was deduced. Investigated oxygen-mediated conditions on the different shaped Fe ion with human serum albumin （HSA）, bovine serum albumin （BSA）, allosteric effects, and the quantitative model equation was established. The results show that the Fe（ II ）-HSA/BSA- Fe（ III ）-HSA/BSA dynamic equilibrium existents in the interaction system between different forms of Fe ions and serum proteins, and the electron transfer effect of Fe（ II ）-HSA/BSA-Fe（ III ）-HSA/BSA in the reaction system of different forms of Fe ions binding with serum protein is a key factor. With the different forms of Fe ions binding with HSA and BSA, the allosteric effect shows totally differEnce, and the significance is relevant to the ion＇s form. The electron transfer mechanism of Fe（ II ）- HSA/BSA-Fe（ III ）-HSA/BSA is different from the anaerobic conditions and oxygen-mediated conditions. Under anaerobic conditions, the interaction of Fe（II ） and serum albumin follows the first-level dynamic reaction rule, and the rate constant k and free energy △G≠ of this interaction system were calculated.

关 键 词：Fe(Ⅱ) Fe(Ⅲ) 别构效应 荷质传递 动力学方程 

分 类 号：O657[理学—分析化学]