Harnessing Redox Cross-Reactivity To Profile Distinct Cysteine Modifications

J Am Chem Soc. 2016 Feb 17;138(6):1852-9. doi: 10.1021/jacs.5b06806. Epub 2016 Feb 5.

Abstract

Cysteine S-nitrosation and S-sulfination are naturally occurring post-translational modifications (PTMs) on proteins induced by physiological signals and redox stress. Here we demonstrate that sulfinic acids and nitrosothiols react to form a stable thiosulfonate bond, and leverage this reactivity using sulfinate-linked probes to enrich and annotate hundreds of endogenous S-nitrosated proteins. In physiological buffers, sulfinic acids do not react with iodoacetamide or disulfides, enabling selective alkylation of free thiols and site-specific analysis of S-nitrosation. In parallel, S-nitrosothiol-linked probes enable enrichment and detection of endogenous S-sulfinated proteins, confirming that a single sulfinic acid can react with a nitrosothiol to form a thiosulfonate linkage. Using this approach, we find that hydrogen peroxide addition increases S-sulfination of human DJ-1 (PARK7) at Cys106, whereas Cys46 and Cys53 are fully oxidized to sulfonic acids. Comparative gel-based analysis of different mouse tissues reveals distinct profiles for both S-nitrosation and S-sulfination. Quantitative proteomic analysis demonstrates that both S-nitrosation and S-sulfination are widespread, yet exhibit enhanced occupancy on select proteins, including thioredoxin, peroxiredoxins, and other validated redox active proteins. Overall, we present a direct, bidirectional method to profile select redox cysteine modifications based on the unique nucleophilicity of sulfinic acids.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Cross Reactions
  • Cysteine / chemistry*
  • Humans
  • Intracellular Signaling Peptides and Proteins / chemistry
  • Nitroso Compounds / chemistry
  • Oncogene Proteins / chemistry
  • Oxidation-Reduction
  • Protein Deglycase DJ-1
  • Sulfhydryl Compounds / chemistry
  • Sulfinic Acids / chemistry

Substances

  • Intracellular Signaling Peptides and Proteins
  • Nitroso Compounds
  • Oncogene Proteins
  • Sulfhydryl Compounds
  • Sulfinic Acids
  • PARK7 protein, human
  • Protein Deglycase DJ-1
  • Cysteine