Related Experiment Video
Updated: Jan 14, 2026
12:11
Simultaneous Affinity Enrichment of Two Post-Translational Modifications for Quantification and Site Localization
Published on: February 27, 2020
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Trivalent chromium interacts directly with acetylated lysine.
Rachel M Wise1, Ting Jiang2, Idoia Meaza3
1Department of Pharmaceutical Sciences, University of New Mexico, Albuquerque, NM, USA; Wise Laboratory on Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, USA.
Summary
Hexavalent chromium (Cr(VI)) toxicity is mediated by its trivalent form (Cr(III)), which directly binds to acetylated lysine residues on proteins. This interaction, particularly with acetylated proteins, is a key mechanism in Cr(VI)-induced cellular damage.
Area of Science:
- Environmental Toxicology
- Molecular Biology
- Proteomics
Background:
- Hexavalent chromium (Cr(VI)) is a known human carcinogen causing systemic toxicity.
- Cr(VI) toxicity mechanisms are not fully understood but may involve protein interactions.
Purpose of the Study:
- To investigate the molecular targets of Cr(VI) and its trivalent form (Cr(III)).
- To compare valence-state-specific protein interactions and identify involved amino acid residues.
Main Methods:
- High-resolution mass spectrometry was used to identify protein targets.
- Analysis of Cr(VI) and Cr(III) interactions with synthesized histone peptides and cellular models.
Main Results:
- Cr(III), not Cr(VI), directly binds to acetylated lysine residues in histone peptides.
- Fifteen Cr-binding proteins were identified in cells exposed to Cr(VI), all showing acetylation.
- Site-specific amino acid interactions were mapped.
Conclusions:
- Cr(VI) exerts toxicity through its intracellularly reduced form, Cr(III).
- Cr(III) directly binds to acetylated lysine residues on proteins.
- Protein acetylation plays a critical role in mediating Cr-induced cellular damage.
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