Skip to Main content Skip to Navigation
Journal articles

Dynamics of a key conformational transition in the mechanism of peroxiredoxin sulfinylation

Abstract : Peroxiredoxins from the Prx1 subfamily (Prx) are moonlighting peroxidases that operate in peroxide signaling and are regulated by sulfinylation. Prxs offer a major model of protein−thiol oxidative modification. They react with H 2 O 2 to form a sulfenic acid intermediate that either engages into a disulfide bond, committing the enzyme into its peroxidase cycle, or again reacts with peroxide to produce a sulfinic acid that inactivates the enzyme. Sensitivity to sulfinylation depends on the kinetics of these two competing reactions and is critically influenced by a structural transition from a fully folded (FF) to locally unfolded (LU) conformation. Analysis of the reaction of the Tsa1 Saccharomyces cerevisiae Prx with H 2 O 2 by Trp fluorescencebased rapid kinetics revealed a process linked to the FF/LU transition that is kinetically distinct from disulfide formation and suggested that sulfenate formation facilitates local unfolding. Use of mutants of distinctive sensitivities and of different peroxide substrates showed that sulfinylation sensitivity is not coupled to the resolving step kinetics but depends only on the sulfenic acid oxidation and FF-to-LU transition rate constants. In addition, stabilization of the active site FF conformation, the determinant of sulfinylation kinetics, is only moderately influenced by the Prx C-terminal tail dynamics that determine the FF → LU kinetics. From these two parameters, the relative sensitivities of Prxs toward hyperoxidation with different substrates can be predicted, as confirmed by in vitro and in vivo patterns of sulfinylation.
Complete list of metadatas

https://hal.univ-lorraine.fr/hal-02473398
Contributor : Julie Gonnet <>
Submitted on : Monday, January 4, 2021 - 11:49:37 AM
Last modification on : Friday, February 5, 2021 - 3:31:52 AM

File

Kriznik et al. - 2020 - Dynami...
Publication funded by an institution

Licence


Distributed under a Creative Commons Attribution - NonCommercial - NoDerivatives 4.0 International License

Identifiers

Citation

Alexandre Kriznik, Marouane Libiad, Hélène Le Cordier, Samia Boukhenouna, Michel Toledano, et al.. Dynamics of a key conformational transition in the mechanism of peroxiredoxin sulfinylation. ACS Catalysis, American Chemical Society, 2020, 10 (5), pp.3326-3339. ⟨10.1021/acscatal.9b04471⟩. ⟨hal-02473398⟩

Share

Metrics

Record views

186

Files downloads

28