化学学报 ›› 2005, Vol. 63 ›› Issue (18): 1759-1764. 上一篇    下一篇

研究论文

Cu2+和铜锌超氧化物歧化酶作用的光谱学研究

盛良全1,2,郑晓云2,童红武2,刘少民2 刘清亮*,2   

  1. (1阜阳师范学院化学系 阜阳 236032)
    (2中国科学技术大学化学与材料学院 合肥 230026)
  • 投稿日期:2005-02-18 修回日期:2005-06-14 发布日期:2010-12-10
  • 通讯作者: 刘清亮

Study on Interaction Between Coper Ion and Hog Liver CuZnSOD by Spectroscopy

SHENG Liang-Quan1,2, ZHENG Xiao-Yun2, TONG Hong-Wu2, LIU Shao-Min b, LIU Qing-Liang*,2   

  1. (1 Department of Chemistry, Fuyang Teacher's College, Fuyang 236032)
    (2 Department of Chemistry, University of Science & Technology of China, Hefei 230026)
  • Received:2005-02-18 Revised:2005-06-14 Published:2010-12-10
  • Contact: LIU Qing-Liang

利用邻苯三酚自氧化法监测在磷酸盐缓冲体系中Cu2+对猪肝铜锌超氧化物歧化酶(CuZnSOD)活力的影响, 认为Cu2+与猪肝CuZnSOD存在直接相互作用. 通过荧光光谱方法研究了这种相互作用, 内源荧光的猝灭实验表明Cu2+与CuZnSOD形成1∶1型稳定配合物; 荧光猝灭的动力学分析表明配合物形成过程由两个独立步骤完成: 第一步是双分子快速缔合过程, 形成了结合疏松的配合物, 第二步是单分子慢速过程, 即松散的配合物“异构化”成为结合紧密的配合物. FTIR和CD证实相互作用过程伴随了蛋白分子构象的变化.

关键词: 铜锌超氧化物歧化酶, 荧光光谱, Cu2+, 猪肝

The influence of copper ion on enzyme activity of hog liver copper zinc superoxide dismutase (CuZnSOD) was monitored by using the pyrogallol autoxidation inhibition assay. The direct interaction of copper ion with CuZnSOD was studied by fluorescence spectroscopy, and a type of 1∶1 stable complex has been generated, which was certified by the quenching experiment of intrinsic fluorescence. The process of the generated complex shown by dynamic analysis of fluorescence quenching, consisted of two steps, in which the first step was a quick association process of double molecules to generate a loose complex, and the second step was a slow process of single molecule, where the loose complex was isomerized into the compact complex. The change of enzyme conformation was due to the binding of Cu2+to SOD, which was confirmed by FTIR and CD spectra.

Key words: CuZnSOD, fluorescence spectroscopy, copper ion, hog liver