Hydroxyl and alkoxyl radical production by oxidation products of metmyoglobin.
Hydroxyl and alkoxyl radical production by oxidation products of metmyoglobin.
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高铁肌红蛋白的氧化产物产生羟基和烷氧基自由基。
DOI：
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发表时间：
1993
期刊：
影响因子：
--
通讯作者：
J. Gómez
中科院分区：
文献类型：
--
作者：
R. Mehlhorn;J. Gómez
ESR检测到还原的氮氧化物（2,2,6,6-四甲基-1,4-二羟基哌替啶，TOLH）的单电子氧化，用于分解和定量血红素蛋白与氢过氧化物反应产生的氧化剂，包括卟啉环氧化裂解后释放的螯合铁。通过分析不同螯合剂存在下TOLH的氧化情况，将释放铁与蛋白质自由基和铁血红素区分。每摩尔血红素用一摩尔H2O2处理肌红蛋白（metMb），产生蛋白质结合氧化剂，每摩尔血红素氧化约两分子TOLH。一些负责TOLH氧化的氧化物种是高度持久的（t1/2在25℃下的衰变是3小时）。比较了过氧化叔丁基（tBH）处理的甲基溶液中铁的释放、甲基漂白和fenton型化学催化作用。释放铁所需的过氧化氢浓度是甲基漂白的5倍。在经tBH和抗坏血酸处理的氧化memb溶液中，memb释放的铁催化了烷氧基和甲基自由基的产生，而蛋白质结合的铁则不催化。结果表明，过氧化氢处理后的甲基黄酮产生的抗坏血酸介导的羟基和烷氧基自由基是由于释放的铁，而在漂白过程中产生的蛋白质结合的非血红素铁最多是一种弱芬顿试剂。
The one-electron oxidation of a reduced nitroxide (2,2,6,6-tetramethyl-1,4-dihydroxypiperidine, TOLH), detected by ESR, was used to resolve and quantify oxidants arising from the reaction of heme proteins with hydroperoxides, including chelatable iron released subsequent to oxidative cleavage of the porphyrin ring. Released iron was distinguished from protein radicals and ferryl heme by analyzing TOLH oxidation in the presence of different chelating agents. Metmyoglobin (metMb) treatment with one mole of H2O2 per mole of heme produced protein-bound oxidants that oxidized about two molecules of TOLH per heme. Some of the oxidizing species responsible for TOLH oxidation were highly persistent (t1/2 for the decay was 3 hrs at 25 degrees C). Iron release, metMb bleaching and the catalysis of Fenton-type chemistry were compared in metMb solutions treated with tert-butyl hydroperoxide (tBH). Iron release required about five-fold higher hydroperoxide concentrations than did metMb bleaching. Alkoxyl and methyl radical production was catalyzed by iron released from metMb but not by protein-bound iron in oxidized metMb solutions treated with tBH and ascorbic acid. The results suggest that ascorbate-mediated hydroxyl and alkoxyl radical production by hydroperoxide-treated metMb is due to released iron and that the protein-bound non-heme iron that arises during bleaching is at most a weak Fenton reagent.
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影响因子：
15.9
作者：
SNYDER, LM;FORTIER, NL;MOHANDAS, N
通讯作者：
MOHANDAS, N
暴露于叔丁基过氧化氢的红细胞中的脂质过氧化和血红蛋白降解。
DOI：
10.1016/0304-4165(81)90211-7
发表时间：
1981
期刊：
Biochimica et biophysica acta
影响因子：
--
作者：
Trotta,RJ;Sullivan,SG;Stern,A
通讯作者：
Stern,A
影响因子：
10.4
作者：
Church DF;Pryor WA
通讯作者：
Pryor WA
影响因子：
3.9
作者：
K. Moore;M. Moronne;R. Mehlhorn
通讯作者：
K. Moore;M. Moronne;R. Mehlhorn
膜蛋白巯基在过氧化氢介导的人红细胞膜损伤中的作用。
DOI：
10.1016/0005-2736(88)90245-3
发表时间：
1988
期刊：
Biochimica et biophysica acta
影响因子：
--
作者：
Snyder,LM;Fortier,NL;Leb,L;McKenney,J;Trainor,J;Sheerin,H;Mohandas,N
通讯作者：
Mohandas,N