title: Moonlighting by different stressors: crystal structure of the chaperone species of a 2-Cys peroxiredoxin.
abstract: 2-Cys peroxiredoxins (Prxs) play two different roles depending on the physiological status of the cell. They are thioredoxin-dependent peroxidases under low oxidative stress and ATP-independent chaperones upon exposure to high peroxide concentrations. These alternative functions have been associated with changes in the oligomerization state from low-(LMW) to high-molecular-weight (HMW) species. Here we present the structures of Schistosoma mansoni PrxI in both states: the LMW decamer and the HMW 20-mer formed by two stacked decamers. The latter is the structure of a 2-Cys Prx chaperonic form. Comparison of the structures sheds light on the mechanism by which chemical stressors, such as high H(2)O(2) concentration and acidic pH, are sensed and translated into a functional switch in this protein family. We also propose a model to account for the in vivo formation of long filaments of stacked Prx rings.
authors.affiliation: Department of Biochemical Sciences, Sapienza University of Rome and Istituto Pasteur-Fondazione Cenci Bolognetti, P.le Aldo Moro 5, 00185 Rome, Italy.
authors.forename: Fulvio
authors.initials: F
authors.lastname: Saccoccia
authors.forename: Patrizio
authors.initials: P
authors.lastname: Di Micco
authors.forename: Giovanna
authors.initials: G
authors.lastname: Boumis
authors.forename: Maurizio
authors.initials: M
authors.lastname: Brunori
authors.forename: Ilias
authors.initials: I
authors.lastname: Koutris
authors.forename: Adriana E
authors.initials: AE
authors.lastname: Miele
authors.forename: Veronica
authors.initials: V
authors.lastname: Morea
authors.forename: Palita
authors.initials: P
authors.lastname: Sriratana
authors.forename: David L
authors.initials: DL
authors.lastname: Williams
authors.forename: Andrea
authors.initials: A
authors.lastname: Bellelli
authors.forename: Francesco
authors.initials: F
authors.lastname: Angelucci
mesh_terms: D000818:Animals; D018360:Crystallography, X-Ray; D008956:Models, Chemical; D008958:Models, Molecular; D018832:Molecular Chaperones / Q000737:chemistry; D009195:Peroxidase / Q000737:chemistry; D054464:Peroxiredoxins / Q000737:chemistry*; D011487:Protein Conformation; D012550:Schistosoma mansoni / Q000737:chemistry*
chemical_list: D018832:Molecular Chaperones; D054464:Peroxiredoxins; D009195:Peroxidase