Skip to main page content
U.S. flag
See More

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Review
. 2004 Nov;2(11):e400.
doi: 10.1371/journal.pbio.0020400. Epub 2004 Nov 16.

Exploiting thiol modifications

Patricia J Kiley  1 , Gisela Storz
Affiliations
Review

Exploiting thiol modifications

Patricia J Kiley et al. PLoS Biol. 2004 Nov.

Abstract

Molecular oxygen may be necessary for life but with its beneficial properties comes formation of potentially toxic reactive oxygen species. One of the ways in which bacteria protect themselves is explained

PubMed Disclaimer

Figures

Figure 1
Figure 1. Formation of Reactive Oxygen Species
The four-electron reduction of molecular O2 generates two molecules of H2O, which is O2 in its most reduced form. While this reduction normally occurs within the enzyme cytochrome oxidase, one-electron transfers to O2 also occur outside of cytochrome oxidase via inadvertent reactions with other reduced electron carriers, resulting in partially reduced and reactive forms of O2· H2O2 is also produced by the enzymatic or spontaneous dismutation of O2 −, and •OH is generated by the reaction of iron with H2O2 (the Fenton reaction). In addition, the reactive oxygen intermediates are produced by a variety of organisms as a defense against microbial invasion. (Illustration: Rusty Howson, sososo design)
Figure 2
Figure 2. Thiol Modifications of Proteins
Formation of sulfenic acid from the reaction of H2O2 with protein thiolates leads to different protein modifications, depending on the protein. In proteins without a second sulfhydryl, the sulfenic acid (–SOH) may be stabilized (e.g., OhrR) or may react with reactive oxygen species to generate the further oxidized sulfinic (–SO2H) (e.g., thiolperoxidase; Tpx) and sulfonic acid (–SO3H) derivatives. Alternatively, if a second cysteinyl residue is in proximity within the same polypeptide (e.g., OxyR) or an associated protein (e.g., Yap1 and Orp1), a disulfide bond can form between the two sulfur atoms (–S–S–). Lastly, the sulfenated cysteinyl residue can react with glutathione (GSH), leading to a mixed disulfide (e.g., MetE). (Illustration: Rusty Howson, sososo design)
See this image and copyright information in PMC

References

    1. Åslund F, Zheng M, Beckwith J, Storz G. Regulation of the OxyR transcription factor by hydrogen peroxide and the cellular thiol-disulfide status. Proc Natl Acad Sci U S A. 1999;96:6161–6165. - PMC - PubMed
    1. Bae JB, Park JH, Hahn MY, Kim MS, Roe JH. Redox-dependent changes in RsrA, an anti-sigma factor in Streptomyces coelicolor: Zinc release and disulfide bond formation. J Mol Biol. 2004;335:425–435. - PubMed
    1. Biteau B, Labarre J, Toledano MB. ATP-dependent reduction of cysteine-sulphinic acid by S. cerevisiae sulphiredoxin. Nature. 2003;425:980–984. - PubMed
    1. Budanov AV, Sablina AA, Feinstein E, Koonin EV, Chumakov PM. Regeneration of peroxiredoxins by p53-regulated sestrins, homologs of bacterial AhpD. Science. 2004;304:596–600. - PubMed
    1. Collet JF, D'Souza JC, Jakob U, Bardwell JC. Thioredoxin 2, an oxidative stress-induced protein, contains a high affinity zinc binding site. J Biol Chem. 2003;278:45325–45332. - PubMed

LinkOut - more resources