Related Experiment Video
Updated: Feb 11, 2026

A Facile and Efficient Approach for the Production of Reversible Disulfide Cross-linked Micelles
Published on: December 23, 2016
Glutaredoxins employ parallel monothiol-dithiol mechanisms to catalyze thiol-disulfide exchanges with protein
Ashwinie A Ukuwela1, Ashley I Bush2, Anthony G Wedd1
1School of Chemistry , Bio21 Molecular Science and Biotechnology Institute , The University of Melbourne , Parkville , Victoria 3010 , Australia.
Abstract:
Glutaredoxins (Grxs) are a family of glutathione (GSH)-dependent thiol-disulfide oxidoreductases. They feature GSH-binding sites that directly connect the reversible redox chemistry of protein thiols to the abundant cellular nonprotein thiol pool GSSG/GSH. This work studied the pathways for oxidation of protein dithiols P(SH)2 and reduction of protein disulfides P(SS) catalyzed by Homo sapiens HsGrx1 and Escherichia coli EcGrx1. The metal-binding domain HMA4n(SH)2 was chosen as substrate as it contains a solvent-exposed CysCys motif. Quenching of the reactions with excess iodoacetamide followed by protein speciation analysis via ESI-MS allowed interception and characterization of both substrate and enzyme intermediates. The enzymes shuttle between three catalytically-competent forms (Grx(SH)(S-), Grx(SH)(SSG) and Grx(SS)) and employ conserved parallel monothiol and dithiol mechanisms. Experiments with dithiol and monothiol versions of both Grx enzymes demonstrate which monothiol (plus GSSG or GSH) or dithiol pathways dominate a specific oxidation or reduction reaction. Grxs are shown to be a class of versatile enzymes with diverse catalytic functions that are driven by specific interactions with GSSG/GSH.
More Related Videos
11:44Synthesis and Structure Determination of µ-Conotoxin PIIIA Isomers with Different Disulfide Connectivities
Published on: October 2, 2018
12:16High Throughput Quantitative Expression Screening and Purification Applied to Recombinant Disulfide-rich Venom Proteins Produced in E. coli
Published on: July 30, 2014
Related Concept Videos
Mechanical Protein Functions
Protein-protein Interfaces
Protein and Protein Structure
A protein's shape is critical to its function. For example, an enzyme...
Protein Organization
Protein Folding
Carboxylic Acids to Esters: Acid-Catalyzed (Fischer) Esterification Mechanism