Chevallet Mireille, Wagner Elsa, Luche Sylvie, van Dorsselaer Alain, Leize-Wagner Emmanuelle, Rabilloud Thierry
Commissariat à l'Energie Atomique-Laboratoire de Bioénergétique Cellulaire et Pathologique, EA 2943, Département Réponses et Dynamique Cellulaire/BioEnergétique Cellulaire et Pathologique-Grenoble, 17 rue des martyrs, F-38054 Grenoble Cedex 9, France.
J Biol Chem. 2003 Sep 26;278(39):37146-53. doi: 10.1074/jbc.M305161200. Epub 2003 Jul 8.
Peroxiredoxins (prx) are redox enzymes using an activated cysteine as their active site. This activated cysteine can be easily overoxidized to cysteine sulfinic acid or cysteine sulfonic acid, especially under oxidative stress conditions. The regeneration of peroxiredoxins after a short, intense oxidative stress was studied, using a proteomics approach. Important differences in regeneration speed were found, prx2 being the fastest regenerated protein, followed by prx1, whereas prx3 and prx6 were regenerated very slowly. Further study of the mechanism of this regeneration by pulse-chase experiments using stable isotope labeling and cycloheximide demonstrated that the fast-regenerating peroxiredoxins are regenerated at least in part by a retroreduction mechanism. This demonstrates that the overoxidation can be reversible under certain conditions. The pathway of this retroreduction and the reasons explaining the various regeneration speeds of the peroxiredoxins remain to be elucidated.
过氧化物酶（Prx）是一类以活化半胱氨酸作为活性位点的氧化还原酶。这种活化半胱氨酸很容易被过度氧化为半胱氨酸亚磺酸或半胱氨酸磺酸，尤其是在氧化应激条件下。采用蛋白质组学方法研究了过氧化物酶在短时间强烈氧化应激后的再生情况。发现再生速度存在重要差异，Prx2是再生最快的蛋白质，其次是Prx1，而Prx3和Prx6的再生非常缓慢。通过使用稳定同位素标记和放线菌酮的脉冲追踪实验对这种再生机制进行的进一步研究表明，快速再生的过氧化物酶至少部分是通过逆向还原机制再生的。这表明在某些条件下，过度氧化可以是可逆的。这种逆向还原的途径以及解释过氧化物酶不同再生速度的原因仍有待阐明。
