Tags

Type your tag names separated by a space and hit enter

Hyperoxidation of peroxiredoxins 2 and 3: rate constants for the reactions of the sulfenic acid of the peroxidatic cysteine.
J Biol Chem. 2013 May 17; 288(20):14170-7.JB

Abstract

Typical 2-Cys peroxiredoxins (Prxs) react rapidly with H2O2 to form a sulfenic acid, which then condenses with the resolving cysteine of the adjacent Prx in the homodimer or reacts with another H2O2 to become hyperoxidized. Hyperoxidation inactivates the Prx and is implicated in cell signaling. Prxs vary in susceptibility to hyperoxidation. We determined rate constants for disulfide formation and hyperoxidation for human recombinant Prx2 and Prx3 by analyzing the relative proportions of hyperoxidized and dimeric products using mass spectrometry as a function of H2O2 concentration (in the absence of reductive cycling) and in competition with catalase at a fixed concentration of H2O2. This gave a second order rate constant for hyperoxidation of 12,000 M(-1) s(-1) and a rate constant for disulfide formation of 2 s(-1) for Prx2. A similar hyperoxidation rate constant for Prx3 was measured, but its rate of disulfide formation was ~10-fold higher, making it is more resistant than Prx2 to hyperoxidation. There are two active sites within the homodimer, and at low H2O2 concentrations one site was hyperoxidized and the other present as a disulfide. Prx with two hyperoxidized sites formed progressively at higher H2O2 concentrations. Although the sulfenic acid forms of Prx2 and Prx3 are ~1000-fold less reactive with H2O2 than their active site thiols, they react several orders of magnitude faster than most reduced thiol proteins. This observation has important implications for understanding the mechanism of peroxide sensing in cells.

Authors+Show Affiliations

Centre for Free Radical Research and Gravida National Centre for Growth and Development, University of Otago, Christchurch 8140, New Zealand. alexander.peskin@otago.ac.nzNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

23543738

Citation

Peskin, Alexander V., et al. "Hyperoxidation of Peroxiredoxins 2 and 3: Rate Constants for the Reactions of the Sulfenic Acid of the Peroxidatic Cysteine." The Journal of Biological Chemistry, vol. 288, no. 20, 2013, pp. 14170-7.
Peskin AV, Dickerhof N, Poynton RA, et al. Hyperoxidation of peroxiredoxins 2 and 3: rate constants for the reactions of the sulfenic acid of the peroxidatic cysteine. J Biol Chem. 2013;288(20):14170-7.
Peskin, A. V., Dickerhof, N., Poynton, R. A., Paton, L. N., Pace, P. E., Hampton, M. B., & Winterbourn, C. C. (2013). Hyperoxidation of peroxiredoxins 2 and 3: rate constants for the reactions of the sulfenic acid of the peroxidatic cysteine. The Journal of Biological Chemistry, 288(20), 14170-7. https://doi.org/10.1074/jbc.M113.460881
Peskin AV, et al. Hyperoxidation of Peroxiredoxins 2 and 3: Rate Constants for the Reactions of the Sulfenic Acid of the Peroxidatic Cysteine. J Biol Chem. 2013 May 17;288(20):14170-7. PubMed PMID: 23543738.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Hyperoxidation of peroxiredoxins 2 and 3: rate constants for the reactions of the sulfenic acid of the peroxidatic cysteine. AU - Peskin,Alexander V, AU - Dickerhof,Nina, AU - Poynton,Rebecca A, AU - Paton,Louise N, AU - Pace,Paul E, AU - Hampton,Mark B, AU - Winterbourn,Christine C, Y1 - 2013/03/29/ PY - 2013/4/2/entrez PY - 2013/4/2/pubmed PY - 2013/8/7/medline KW - Hydrogen Peroxide KW - Hyperoxidation KW - Oxidation-Reduction KW - Peroxiredoxin KW - Redox Signaling KW - Signal Transduction KW - Sulfenic Acid KW - Thiol SP - 14170 EP - 7 JF - The Journal of biological chemistry JO - J. Biol. Chem. VL - 288 IS - 20 N2 - Typical 2-Cys peroxiredoxins (Prxs) react rapidly with H2O2 to form a sulfenic acid, which then condenses with the resolving cysteine of the adjacent Prx in the homodimer or reacts with another H2O2 to become hyperoxidized. Hyperoxidation inactivates the Prx and is implicated in cell signaling. Prxs vary in susceptibility to hyperoxidation. We determined rate constants for disulfide formation and hyperoxidation for human recombinant Prx2 and Prx3 by analyzing the relative proportions of hyperoxidized and dimeric products using mass spectrometry as a function of H2O2 concentration (in the absence of reductive cycling) and in competition with catalase at a fixed concentration of H2O2. This gave a second order rate constant for hyperoxidation of 12,000 M(-1) s(-1) and a rate constant for disulfide formation of 2 s(-1) for Prx2. A similar hyperoxidation rate constant for Prx3 was measured, but its rate of disulfide formation was ~10-fold higher, making it is more resistant than Prx2 to hyperoxidation. There are two active sites within the homodimer, and at low H2O2 concentrations one site was hyperoxidized and the other present as a disulfide. Prx with two hyperoxidized sites formed progressively at higher H2O2 concentrations. Although the sulfenic acid forms of Prx2 and Prx3 are ~1000-fold less reactive with H2O2 than their active site thiols, they react several orders of magnitude faster than most reduced thiol proteins. This observation has important implications for understanding the mechanism of peroxide sensing in cells. SN - 1083-351X UR - https://www.unboundmedicine.com/medline/citation/23543738/Hyperoxidation_of_peroxiredoxins_2_and_3:_rate_constants_for_the_reactions_of_the_sulfenic_acid_of_the_peroxidatic_cysteine_ L2 - http://www.jbc.org/cgi/pmidlookup?view=long&pmid=23543738 DB - PRIME DP - Unbound Medicine ER -