荧光光谱分析超氧化物歧化酶的构象变化及其功能  

Fluorescence Spectra Analysis of Conformational Changes and Its Function of Superoxide Dismutase

作　　者：李阳[1] 赵怡[1] 谢丽思[1] 李任强[1] 

机构地区：[1]暨南大学生物工程学系,广州市黄埔大道西601号510632

出　　处：《光谱实验室》2011年第6期2763-2769,共7页Chinese Journal of Spectroscopy Laboratory

基　　金：暨南大学自然科学基金(640073)

摘　　要：通过荧光光谱研究了枯草芽孢杆菌超氧化物歧化酶(SOD)的分子构象在不同浓度盐酸胍、尿素以及不同pH条件下的变化及其与功能的关系。结果表明,SOD构象与功能的变化与其荧光光谱的变化有明显的对应关系。随着盐酸胍浓度的增加,SOD发射峰红移,荧光强度不断下降,且这两种变化同步发生;酶则出现快失活慢变构现象。而利用尿素变性SOD时,SOD先是荧光强度增强,然后发射峰红移,酶活力的下降与构象变化同步进行。尿素和盐酸胍使SOD变性的机理明显不同。处于不同酸碱度时,SOD活力的变化与荧光光谱所表现出的构象变化几乎一致。通过荧光分析法是可以对不同条件下SOD分子的构象变化及其酶活进行快速测定的。The molecular conformational changes of bacillus subtilis superoxide dismutase（SOD） and the relationship of conformations with functions were investigated by fluorescence spectra in the different concentrations and pH value of GuHCl and urea.Changes of conformation with function of SOD were well reflected on their fluorescence spectra.The emission peaks of SOD appeared red-shifted along with increase of GuHCl concentration and decrease of fluorescence intensity,and the two changes occurred,simultaneously,while the enzyme appeared proksim inactivation and slow allosterism.With denaturation of SOD by urea,firstly,the fluorescence intensity of SOD was increased,then the emission peaks were appeared red-shifted,and the decrease of enzymatic activity and conformational changes simultaneously occurred.The denaturation mechanisations of SOD by GuHCl and urea were obviously different.The changes of SOD activity were almost agree with conformational changes of fluorescence spectra.The molecular conformational changes of SOD and its enzymatic activity were quickly determined by fluorescence analysis under different conditions.

关 键 词：荧光光谱 超氧化物歧化酶 构象变化 酶活力 

分 类 号：O657.32[理学—分析化学]