过氧化物模拟酶空间结构及介质微环境对酶催化反应的影响  

The Influence of Spatial Structures of Mimetic Peroxidases and Medium Microheterogenous for Enzyme Catalytic Reaction

作　　者：黄应平[1] 罗光富[1] 罗勇军[1] 蔡汝秀[2] 

机构地区：[1]三峡大学化学系,宜昌443002 [2]武汉大学化学系,武汉430072

出　　处：《分析化学》2005年第5期599-604,共6页Chinese Journal of Analytical Chemistry

基　　金：国家自然科学基金资助项目(No.20373074);湖北省教育厅自然科学重大基金资助项目(No.2004Z001)

摘　　要：在水溶液及胶束介质中分别研究了血红蛋白(hemoglobin,Hb),β环糊精氯化血红素(βCDhemin)和氯化血红素(hemin)作为过氧化物模拟酶对隐性亮绿(recessivebrilliantgreen,RBG)H2O2(或溶解氧)体系的催化特性。在Tween80存在下,通过测定米氏常数Km和Vmax,比较了酶催化活性的大小,结果表明催化活性Hb>βCDhemin>hemin。分别研究了辣根过氧化物酶(horseradishperoxidase,HRP),βCDhemin,hemin和四羧基苯基锰卟啉(MnTCPP)对4氨基安替比林(4AAP)2,3,4三氯苯酚(2,3,4trichlorophenol,TCP)体系的催化显色作用,酶及模拟酶催化活性比较为HRP>βCDhemin>hemin>MnTCPP。根据实验结果,讨论了胶束介质对RGB溶解氧催化体系的作用方式以及4AAPTCP酶催化体系的MichaeliMenten方程,并从不同空间结构(结合部位)模拟过氧化物酶催化性能的角度讨论了结合部位在酶催化反应中的有效作用。The catalytic characteristics of various mimetic peroxidases (hemoglobin (HB), beta-ccylodextrin (beta-CD) hemin and hemin) for recessive brilliant green (RBG)-H2O2 (or resolved oxygen) system were studied both in aqueous solution and micelles. The order of catalytic activity of these catalysts is HB > beta-CD-hemin > hemin on the basis of the michaelis constants (V-max, K-m) in the presence of Tween-80. In the same way, the catalytic characteristic of horseradish peroxidase (HRP), beta-CD-hemin, hemin and manganese-Tetracarboxy-phenylporphyrin (MnTCPP) is compared using 4-aminoantipyrin (4-AAP)-2, 3, 4-trichloriphenol (TCP) catalytic system. The result indicats HRP > beta-CD-hemin > hemin > MnTCPP. The action of micelle on RBG-resolved oxygen reaction is discussed from experimental results, and the michali-menten equations of the 4-AAP-TCP system obtained from catalytic activities of these catalysts is compared through calculated michaelis constants (V-max, K-m). Further influences of spatial structures (binding site) and microheterogeneous on catalytic reaction were studied.

关 键 词：过氧化物 酶 空间结构 介质微环境 催化反应 

分 类 号：O643.3[理学—物理化学]