title: Glutathionylation of the Active Site Cysteines of Peroxiredoxin 2 and Recycling by Glutaredoxin.
abstract: Peroxiredoxin 2 (Prx2) is a thiol protein that functions as an antioxidant, regulator of cellular peroxide concentrations, and sensor of redox signals. Its redox cycle is widely accepted to involve oxidation by a peroxide and reduction by thioredoxin/thioredoxin reductase. Interactions of Prx2 with other thiols are not well characterized. Here we show that the active site Cys residues of Prx2 form stable mixed disulfides with glutathione (GSH). Glutathionylation was reversed by glutaredoxin 1 (Grx1), and GSH plus Grx1 was able to support the peroxidase activity of Prx2. Prx2 became glutathionylated when its disulfide was incubated with GSH and when the reduced protein was treated with H2O2 and GSH. The latter reaction occurred via the sulfenic acid, which reacted sufficiently rapidly (k = 500 m(-1) s(-1)) for physiological concentrations of GSH to inhibit Prx disulfide formation and protect against hyperoxidation to the sulfinic acid. Glutathionylated Prx2 was detected in erythrocytes from Grx1 knock-out mice after peroxide challenge. We conclude that Prx2 glutathionylation is a favorable reaction that can occur in cells under oxidative stress and may have a role in redox signaling. GSH/Grx1 provide an alternative mechanism to thioredoxin and thioredoxin reductase for Prx2 recycling.
authors.affiliation: From the Centre for Free Radical Research, University of Otago Christchurch, Christchurch 8140, New Zealand and.
authors.forename: Alexander V
authors.initials: AV
authors.lastname: Peskin
authors.affiliation: From the Centre for Free Radical Research, University of Otago Christchurch, Christchurch 8140, New Zealand and.
authors.forename: Paul E
authors.initials: PE
authors.lastname: Pace
authors.affiliation: Vascular Biology Section and Cardiovascular Proteomics Center, Department of Medicine, Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, Massachusetts 02118.
authors.forename: Jessica B
authors.initials: JB
authors.lastname: Behring
authors.affiliation: From the Centre for Free Radical Research, University of Otago Christchurch, Christchurch 8140, New Zealand and.
authors.forename: Louise N
authors.initials: LN
authors.lastname: Paton
authors.affiliation: From the Centre for Free Radical Research, University of Otago Christchurch, Christchurch 8140, New Zealand and.
authors.forename: Marjolein
authors.initials: M
authors.lastname: Soethoudt
authors.affiliation: Vascular Biology Section and Cardiovascular Proteomics Center, Department of Medicine, Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, Massachusetts 02118.
authors.forename: Markus M
authors.initials: MM
authors.lastname: Bachschmid
authors.affiliation: From the Centre for Free Radical Research, University of Otago Christchurch, Christchurch 8140, New Zealand and christine.winterbourn@otago.ac.nz.
authors.forename: Christine C
authors.initials: CC
authors.lastname: Winterbourn
mesh_terms: D000818:Animals; D020134:Catalytic Domain; D002460:Cell Line; D003545:Cysteine; D054477:Glutaredoxins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D005978:Glutathione / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D006801:Humans; D006861:Hydrogen Peroxide / Q000737:chemistry; D051379:Mice; D018345:Mice, Knockout; D018384:Oxidative Stress / Q000187:drug effects; D054464:Peroxiredoxins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D011499:Protein Processing, Post-Translational / Q000502:physiology*; D013880:Thioredoxin-Disulfide Reductase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D013879:Thioredoxins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism
chemical_list: C516006:Glrx protein, mouse; D054477:Glutaredoxins; D013879:Thioredoxins; D006861:Hydrogen Peroxide; C086065:PRDX2 protein, human; D054464:Peroxiredoxins; D013880:Thioredoxin-Disulfide Reductase; D005978:Glutathione; D003545:Cysteine
keywords: glutaredoxin; glutathionylation; hydrogen peroxide; mass spectrometry (MS); peroxiredoxin; redox regulation