利用复合-解离型超分子开关构建智能人工碲酶  

Construction of Smart Artificial Tellurase Based on the Composite-dissociatedSupramolecular Switch

作　　者：李思 刘琳琳 李佳锡 金耀程[2] LI Si;LIU Lin-lin;LI Jia-xi;JIN Yao-cheng(Materials Science and Engineering College,Shenyang University of Chemical Technology,Shenyang 110142,China;Shenyang Fourth Rubber(Factory)Company,Shenyang 110077,China)

机构地区：[1]沈阳化工大学材料科学与工程学院,沈阳110142 [2]沈阳第四橡胶(厂)有限公司,沈阳110077

出　　处：《科学技术与工程》2024年第34期14590-14598,共9页Science Technology and Engineering

基　　金：辽宁省教育厅科学研究青年项目(LJKQ20222422)。

摘　　要：谷胱甘肽过氧化物酶(GPx)在化学性质和结构组成上是一种研究较全面的硒酶,在保护细胞免受沿海应激方面发挥重要作用。为了更好地模拟生命体内细微pH差异下GPx酶的运作机制,制备pH响应性GPx人工智能酶更受广泛关注。设计并合成了同时具备谷胱甘肽过氧化物酶(GPx)催化中心和两个仲胺基团的N-乙基乙胺单碲醚分子,其能够展现出最高的(1.43±0.01)μmol/(min·μmol)比活力值,酶促反应动力学曲线表明其催化方式为有序顺序机制,二级反应速率常数可达到10^(1)~10^(2) L/(mol·min)数量级。pH=6时,N-乙基乙胺单碲醚分子的两个仲胺基团处于双质子化状态,因此能够与葫芦[6]脲(CB[6])复合形成超分子开关,此时催化中心包埋于CB[6]的疏水空腔中,催化活性仅为(0.18±0.01)μmol/(min·μmol),人工酶活性处于关闭状态;pH=7时,超分子开关部分解离,从而展现出(0.67±0.02)μmol/(min·μmol)的催化活性,人工酶活性处于最佳开启状态。因此,本文构建的超分子开关可以在生命体pH为6~7的范围内实现复合与解离,从而控制人工酶催化活性的关闭与开启,为构建pH响应性GPx人工酶提供了新的方法和思路。GPx(glutathione peroxidase)is a well-studied selenase in terms of chemical properties and structure,which plays an important role in protecting cells from oxidative stress.In order to better restore the operation mechanism of GPx enzyme under the subtle pH differences in life entity,the preparation of PH-responsive GPx artificial intelligence enzyme has attracted more attention.N-ethylethylamine monotelluride molecule with GPx catalytic center and two secondary amine groups was designed and synthesized.The maximum specific activity value of the molecule was(1.43±0.01)μmol/(min·μmol),the kinetics curve of the enzymatic reaction show that the catalytic mode is an ordered sequence mechanism,and the second-order reaction rate constant could reach the order of 10^(1)~10^(2) L/(mol·min).At pH=6,the two secondary amine groups of N-ethylethylamine monotelluride molecule is in the double protonation state,so it could compound with cucurbit[6](CB[6])to form a supramolecular switch.At this time,the catalytic center is embedded in the hydrophobic cavity of CB[6],and the catalytic activity is only(0.18±0.01)μmol/(min·μmol),the artificial enzyme activity is in the off state.At pH=7,the supramolecular switch is partially dissociated,which showed the catalytic activity of(0.67±0.02)μmol/(min·μmol),and the artificial enzyme activity is in the best opening state.Therefore,the supramolecular switch constructed in this paper realized recombination and dissociation in the pH range of living organisms(between 6 and 7),so as to control the off and on of the catalytic activity,providing a new method and idea for constructing Ph-responsive GPx artificial enzymes.

关 键 词：谷胱甘肽过氧化物酶 超分子开关 PH响应性 生物催化 

分 类 号：Q554.6[生物学—生物化学]