基于光谱法研究盐酸胍诱导的人血红蛋白去折叠过程  

Spectroscopic Studies of Guanidine Hydrochloride-Induced Unfolding of Hemoglobin

作　　者：李进京[1] 唐乾[1,2] 曹洪玉[1,2] 张玉姣[1] 张涛[1] 郑学仿[1,2] 

机构地区：[1]大连大学生命科学与技术学院,辽宁大连116622 [2]大连大学,辽宁省生物有机化学重点实验室,辽宁大连116622

出　　处：《光谱学与光谱分析》2012年第9期2496-2500,共5页Spectroscopy and Spectral Analysis

基　　金：国家自然科学基金项目(20871024);辽宁省高校创新团队项目(2006T002,2008T005,2009T003,2010T003);大连市科技计划项目(2008E11SF170)资助

摘　　要：借助于紫外-可见吸收光谱法、荧光光谱法以及停流-荧光光谱法研究了盐酸胍(GdmHcl)诱导人血红蛋白的去折叠过程。实验发现,盐酸胍诱导的血红蛋白去折叠有两个不同的过程,即随着GdmHcl浓度增加到1.0mol·L-1左右时,血红蛋白亚基发生解聚,形成中间态;持续增加其浓度时,各亚基发生内部去折叠,最终导致血红素发生崩解。加入还原剂(β-巯基乙醇)对血红蛋白亚基解聚、血红素崩解有协同作用且直接引起亚基和全分子同步变构。血红蛋白去折叠过程从"三态模型"转变为"二态模型"。In the present paper,based on the ultraviolet-visible（UV-Vis） absorption spectroscopy,fluorescence spectroscopy,and stopped flow-fluorescence spectroscopy,the authors studied the protein unfolding process of hemoglobin induced by GdmHcl.The experiments result shows that there were two different procedures about GdmHcl inducing hemoglobin unfolding from the evidences of UV-Vis absorption spectrum and fluorescence phase diagrams.Namely,the hemoglobin subunit exhibits depolymerization,forming the intermediates when incubated with GdmHcl at the concentration of 1.0 mol·L-1.With the increase in the concentration,various subunit structure became loose gradually,and the protoheme collapsed eventually.UV-Vis absorption spectroscopy indicates that the addition of reductant can cooperate with the depolymerization of hemoglobin subunit and the disaggregation of protoheme.The reductant results in the unfolding procedure that hemoglobin from ＂three-state model＂ turns into ＂two-state model＂.

关 键 词：光谱法 血红蛋白 盐酸胍 去折叠 中间态 

分 类 号：Q518.4[生物学—生物化学]