Related Experiment Video
Updated: Aug 4, 2026

Profiling Thiol Redox Proteome Using Isotope Tagging Mass Spectrometry
Published on: March 24, 2012
Rhodanese as a thioredoxin oxidase
D L Nandi1, P M Horowitz, J Westley
1Department of Biochemistry and Molecular Biology, The University of Chicago, IL 60637, USA.
Two bovine liver mitochondrial rhodanese isoforms exhibit distinct catalytic activities. One isoform oxidizes reduced thioredoxin, suggesting a role in detoxifying oxygen free radicals within mitochondria.
Area of Science:
- Biochemistry
- Mitochondrial Biology
- Enzymology
Background:
- Rhodanese (thiosulfate: cyanide sulfurtransferase, EC 2.8.1.1) is a key mitochondrial enzyme.
- Two common isoforms of bovine liver mitochondrial rhodanese exist.
- Understanding rhodanese isoform function is crucial for mitochondrial redox homeostasis.
Purpose of the Study:
- To investigate the catalytic differences between bovine liver mitochondrial rhodanese isoforms.
- To elucidate the mechanism of thioredoxin interaction with rhodanese isoforms.
- To explore the potential role of rhodanese in reactive oxygen species detoxification.
Main Methods:
- Enzyme kinetics assays comparing rhodanese isoforms.
- Characterization of substrate specificity with reduced thioredoxin.
- Analysis of rhodanese activity in the presence of reactive oxygen species.
Main Results:
- Both rhodanese isoforms accept sulfur from thiosulfate and transfer it to reduced thioredoxin.
- Only the less negative rhodanese isoform, similar to recombinant mammalian rhodanese, directly oxidizes reduced thioredoxin.
- This oxidation is linked to reactive oxygen species and involves sulfenic acid intermediates.
Conclusions:
- A significant catalytic divergence exists between bovine liver mitochondrial rhodanese isoforms.
- One isoform possesses thioredoxin oxidase activity, potentially involving reactive oxygen species.
- This suggests a specific role for this rhodanese isoform in mitigating intramitochondrial oxidative stress.
More Related Videos
08:57Simultaneous Measurement of Superoxide/Hydrogen Peroxide and NADH Production by Flavin-containing Mitochondrial Dehydrogenases
Published on: February 24, 2018
07:16Resin-Assisted Capture Coupled with Isobaric Tandem Mass Tag Labeling for Multiplexed Quantification of Protein Thiol Oxidation
Published on: June 21, 2021
Related Concept Videos
Redox Reactions
Oxidation-Reduction Reactions
Preparation and Reactions of Thiols
Oxidation of Phenols to Quinones
o-hydroxy phenols are oxidized to o-quinones and p-hydroxy phenols to p-quinones. Such redox reactions involve the transfer of two electrons and two protons. The reversible redox property is crucial in...
Electron Transport Chain: Complex III and IV
Redox Reactions