GSH对两种谷胱甘肽过氧化物酶模拟物活性影响的研究

设计并合成了谷胱甘肽过氧化物酶(GPX)模拟物6A,6A’-二苯胺-6B,6B’-二硒桥联-β-环糊精(6-AnSeCD). 采用双酶偶联法测定GPX的活力结果显示, 6A,6A’-二环己胺-6B,6B’-二硒桥联-β-环糊精(6-CySeCD)催化谷胱甘肽还原H2O2和枯烯H2O2的活力均比6-AnSeCD的高. 为了进一步考察6-CySeCD和6-AnSeCD与GSH之间的相互作用, 进行了分子动力学(MD)模拟和分子对接研究. 结果表明, 与GSH的结合使GPX模拟物的构象发生变化, 这种改变可能是影响桥连GPX模拟物催化活性的关键因素.

Effects of GSH on the Activity of Two Glutathione Peroxidase Mimics

6A,6A’-dianilino-6B,6B’-diselenide-bis-β-cyclodextrin(6-AnSeCD) was designed and synthesized to imitate the antioxidant enzyme glutathione peroxidase(GPX). The GPX activities of 6-AnSeCD and 6A,6A’-dicyclohexylamine-6B,6B’-diselenide-bis-β-cyclodextrin(6-CySeCD) were assessed in classical coupled reductase assay. 6-CySeCD exhibits better GPX activity than 6-AnSeCD in the reduction of H2O2 and cumenyl hydroperoxide by glutathione, respectively. And then, with the molecular dynamics(MD) simulations, the interaction between GPX mimics(6-CySeCD and 6-AnySeCD) and GSH were investigated. The MD results show great differences in the conformation and bond lengths between the each GPX mimics and the its substrate-enzyme complex, which demonstrate the possibility that such change might be the key factor for the bridge GPX mimics’ catalysis.