6A,6A′-苯胺-6B,6B′-硒桥联-β-CD底物的特异性

运用双酶偶联体系分别测定6A,6A′-二苯胺-6B,6B′-二硒桥联-β-CD（6-AnSeCD）催化谷胱甘肽（GSH）还原过氧化氢（H₂O₂）、 叔丁基过氧化氢（t- BuOOH）和枯烯过氧化氢（CumOOH）3种结构不同氢过氧化物的谷胱甘肽过氧化物酶（GPx）活力, 并考察6-AnSeCD催化这3种氢过氧化物的稳态动力学. 结果表明: 6 AnSeCD还原CumOOH的GPx活力最高; 6-AnSeCD的催化机制为乒乓机制; 6 AnSeCD的假一级反应速度常数（k_max）、 米氏常数（K_m）和二级反应速率常数（k）均显示CumOOH为6-AnSeCD的最适底物.

Substrate Specificity of 6A,6A′-Dianilino-6B,6B′-diselenide-bis-β-cyclodextrin

The gluathione peroxidase (GPx) activities of 6A,6A′-dianilino-6B,6B′-diselenide-bis-β-cyclodextrin (6-AnSeCD) in the reduction of H₂O₂, tert butylhydroperoxide (t-BuOOH) and cumenyl hydroperoxide (CumOOH) by glutathione (GSH) were assessed in classical coupled reductase assay, and the steady state kinetics of 6 AnSeCD in the reduction of three hydrogen peroxides was studied. The 6-AnSeCD displayed best GPx activity for the reduction of CumOOH by GSH. A ping pong mechanism was observed in the steady state kinetic studies on the 6-AnSeCD catalyzed reactions. We further compared k_max, K_m and second order rate constant of 6-AnSeCD. Theresults show the CumOOH is the most preferred substrate for 6-AnSeCD.