title: Glutathionylation of Pea Chloroplast 2-Cys Prx and Mitochondrial Prx IIF Affects Their Structure and Peroxidase Activity and Sulfiredoxin Deglutathionylates Only the 2-Cys Prx.
abstract: Together with thioredoxins (Trxs), plant peroxiredoxins (Prxs), and sulfiredoxins (Srxs) are involved in antioxidant defense and redox signaling, while their regulation by post-translational modifications (PTMs) is increasingly regarded as a key component for the transduction of the bioactivity of reactive oxygen and nitrogen species. Among these PTMs,S-glutathionylation is considered a protective mechanism against overoxidation, it also modulates protein activity and allows signaling. This study explores the glutathionylation of recombinant chloroplastic 2-Cys Prx and mitochondrial Prx IIF fromPisum sativum. Glutathionylation of the decameric form of 2-Cys Prx produced a change in the elution volume after FPLC chromatography and converted it to its dimeric glutathionylated form, while Prx IIF in its reduced dimeric form was glutathionylated without changing its oligomeric state. Mass spectrometry demonstrated that oxidized glutathione (GSSG) can glutathionylate resolving cysteine (Cys174), but not the peroxidatic equivalent (Cys52), in 2-Cys Prx. In contrast, GSSG was able to glutathionylate both peroxidatic (Cys59) and resolving (Cys84) cysteine in Prx IIF. Glutathionylation was seen to be dependent on the GSH/GSSG ratio, although the exact effect on the 2-Cys Prx and Prx IIF proteins differed. However, the glutathionylation provoked a similar decrease in the peroxidase activity of both peroxiredoxins. Despite growing evidence of the importance of post-translational modifications, little is known about the enzymatic systems that specifically regulate the reversal of this modification. In the present work, sulfiredoxin fromP. sativumwas seen to be able to deglutathionylate pea 2-Cys Prx but not pea Prx IIF. Redox changes during plant development and the response to stress influence glutathionylation/deglutathionylation processes, which may represent an important event through the modulation of peroxiredoxin and sulfiredoxin proteins.
authors.affiliation: Department of Stress Biology and Plant Pathology, Centre for Applied Soil Science and Biology of the Segura - Consejo Superior de Investigaciones Científicas Murcia, Spain.
authors.forename: Aingeru
authors.initials: A
authors.lastname: Calderón
authors.affiliation: Department of Biochemistry, Cellular and Molecular Biology of Plants, Zaidin Experimental Station - Consejo Superior de Investigaciones Científicas Granada, Spain.
authors.forename: Alfonso
authors.initials: A
authors.lastname: Lázaro-Payo
authors.affiliation: Department of Biochemistry, Cellular and Molecular Biology of Plants, Zaidin Experimental Station - Consejo Superior de Investigaciones Científicas Granada, Spain.
authors.forename: Iván
authors.initials: I
authors.lastname: Iglesias-Baena
authors.affiliation: Department of Stress Biology and Plant Pathology, Centre for Applied Soil Science and Biology of the Segura - Consejo Superior de Investigaciones Científicas Murcia, Spain.
authors.forename: Daymi
authors.initials: D
authors.lastname: Camejo
authors.affiliation: Department of Biochemistry, Cellular and Molecular Biology of Plants, Zaidin Experimental Station - Consejo Superior de Investigaciones Científicas Granada, Spain.
authors.forename: Juan J
authors.initials: JJ
authors.lastname: Lázaro
authors.affiliation: Department of Stress Biology and Plant Pathology, Centre for Applied Soil Science and Biology of the Segura - Consejo Superior de Investigaciones Científicas Murcia, Spain.
authors.forename: Francisca
authors.initials: F
authors.lastname: Sevilla
authors.affiliation: Department of Stress Biology and Plant Pathology, Centre for Applied Soil Science and Biology of the Segura - Consejo Superior de Investigaciones Científicas Murcia, Spain.
authors.forename: Ana
authors.initials: A
authors.lastname: Jiménez
keywords: 2-Cys peroxiredoxin; glutathione redox state; glutathionylation; peroxiredoxin IIF; post-translational modification; reactive nitrogen species; reactive oxygen species; sulfiredoxin