{"title":"重组人细胞质和线粒体NADPH:硫氧还蛋白还原酶氧化还原特性的比较研究","authors":"Lina Misevičienė, K. Krikštopaitis, N. Čėnas","doi":"10.6001/chemija.v33i2.4707","DOIUrl":null,"url":null,"abstract":"We compared the redox properties of recombinant cytosolic (TrxR1) and mitochondrial (TrxR2) isoforms of human flavosulfoselenoenzyme NADPH:thioredoxin reductase. The standard redox potentials of isoenzymes (E0 7), determined according to the redox equilibrium with the NADP+/NADPH couple, were equal to –0.295 V (TrxR1) and –0.270 V (TrxR2). The more positive value of E0 7 of TrxR2 may be attributed to the presence of His-125 at the vicinity of catalytic disulfide and selenylsulfide, instead of Tyr-116 in TrxR1. The reactivity of several quinones and nitroaromatic compounds towards TrxR1 and TrxR2 increased with their single-electron reduction potential (E1 7). For the first time, we studied the TrxR1-catalysed reduction of a series of aromatic N-oxides which were reduced in a mixed single- and two-electron way. Their reactivity was close to that of quinones and nitroaromatics with the similar values of E1 7.","PeriodicalId":9720,"journal":{"name":"Chemija","volume":" ","pages":""},"PeriodicalIF":0.5000,"publicationDate":"2022-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"The comparative study of redox properties of recombinant human cytosolic and mitochondrial NADPH: thioredoxin reductases\",\"authors\":\"Lina Misevičienė, K. Krikštopaitis, N. Čėnas\",\"doi\":\"10.6001/chemija.v33i2.4707\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"We compared the redox properties of recombinant cytosolic (TrxR1) and mitochondrial (TrxR2) isoforms of human flavosulfoselenoenzyme NADPH:thioredoxin reductase. The standard redox potentials of isoenzymes (E0 7), determined according to the redox equilibrium with the NADP+/NADPH couple, were equal to –0.295 V (TrxR1) and –0.270 V (TrxR2). The more positive value of E0 7 of TrxR2 may be attributed to the presence of His-125 at the vicinity of catalytic disulfide and selenylsulfide, instead of Tyr-116 in TrxR1. The reactivity of several quinones and nitroaromatic compounds towards TrxR1 and TrxR2 increased with their single-electron reduction potential (E1 7). For the first time, we studied the TrxR1-catalysed reduction of a series of aromatic N-oxides which were reduced in a mixed single- and two-electron way. Their reactivity was close to that of quinones and nitroaromatics with the similar values of E1 7.\",\"PeriodicalId\":9720,\"journal\":{\"name\":\"Chemija\",\"volume\":\" \",\"pages\":\"\"},\"PeriodicalIF\":0.5000,\"publicationDate\":\"2022-05-04\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Chemija\",\"FirstCategoryId\":\"92\",\"ListUrlMain\":\"https://doi.org/10.6001/chemija.v33i2.4707\",\"RegionNum\":4,\"RegionCategory\":\"化学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q4\",\"JCRName\":\"CHEMISTRY, MULTIDISCIPLINARY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Chemija","FirstCategoryId":"92","ListUrlMain":"https://doi.org/10.6001/chemija.v33i2.4707","RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"CHEMISTRY, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
摘要
我们比较了重组人黄磺基硒酶NADPH:硫氧还蛋白还原酶的细胞质(TrxR1)和线粒体(TrxR2)异构体的氧化还原特性。根据NADP+/NADPH对氧化还原平衡测定的同工酶(e07)的标准氧化还原电位分别为-0.295 V (TrxR1)和-0.270 V (TrxR2)。TrxR2的e07较高的正值可能是由于His-125存在于催化二硫化物和硒基硫化物附近，而不是TrxR1中的tyrl -116。几种醌类和硝基芳香化合物对TrxR1和TrxR2的反应活性随着其单电子还原电位的增加而增加(E1 7)。我们首次研究了TrxR1催化的一系列芳香n -氧化物的单电子和双电子混合还原。它们的反应活性接近醌类和硝基芳烃类，E1 - 7值相近。
The comparative study of redox properties of recombinant human cytosolic and mitochondrial NADPH: thioredoxin reductases
We compared the redox properties of recombinant cytosolic (TrxR1) and mitochondrial (TrxR2) isoforms of human flavosulfoselenoenzyme NADPH:thioredoxin reductase. The standard redox potentials of isoenzymes (E0 7), determined according to the redox equilibrium with the NADP+/NADPH couple, were equal to –0.295 V (TrxR1) and –0.270 V (TrxR2). The more positive value of E0 7 of TrxR2 may be attributed to the presence of His-125 at the vicinity of catalytic disulfide and selenylsulfide, instead of Tyr-116 in TrxR1. The reactivity of several quinones and nitroaromatic compounds towards TrxR1 and TrxR2 increased with their single-electron reduction potential (E1 7). For the first time, we studied the TrxR1-catalysed reduction of a series of aromatic N-oxides which were reduced in a mixed single- and two-electron way. Their reactivity was close to that of quinones and nitroaromatics with the similar values of E1 7.
期刊介绍：
Chemija publishes original research articles and reviews from all branches of modern chemistry, including physical, inorganic, analytical, organic, polymer chemistry, electrochemistry, and multidisciplinary approaches.
京公网安备 11010802042870号
京ICP备2023020795号-1
分享
求助内容：
应助结果提醒方式：
扫码关注我们
