Related Experiment Video
Updated: Jun 22, 2026
07:16
Resin-Assisted Capture Coupled with Isobaric Tandem Mass Tag Labeling for Multiplexed Quantification of Protein Thiol Oxidation
Published on: June 21, 2021
Methods for the determination and quantification of the reactive thiol proteome
Bradford G Hill1, Colin Reily, Joo-Yeun Oh
1Center for Free Radical Biology, Department of Pathology, University of Alabama at Birmingham, Birmingham, AL 35294-0022, USA.
Free Radical Biology & Medicine
|June 17, 2009
Summary
This study introduces a new method for detecting protein thiol modifications using labeled alkylating agents and external standards. This technique enables sensitive quantification of thiol changes in biological samples.
Area of Science:
- Biochemistry
- Proteomics
- Chemical Biology
Background:
- Protein thiol modifications are crucial in physiological and pathological processes, affecting protein structure, function, and redox signaling.
- The reactive thiol proteome, primarily low-abundance proteins with low pKa cysteine residues, requires sensitive detection methods.
- Existing methods may lack the sensitivity and quantitative accuracy needed for studying these modifications.
Purpose of the Study:
- To standardize the use of biotinylated and fluorophore-labeled alkylating agents for thiol modification detection.
- To develop a quantitative proteomic strategy for measuring protein thiol modifications in biological samples.
- To provide a detailed protocol for visualizing and quantifying thiol modifications using external standards.
Main Methods:
- Standardization of biotinylated (e.g., biotin-iodoacetamide, biotin-N-ethylmaleimide) and fluorophore-labeled (e.g., BODIPY-IAM, BODIPY-NEM) alkylating agents.
- Development of one- and two-dimensional proteomic strategies incorporating these probes.
- Creation of external standards using purified proteins (cytochrome c, glyceraldehyde-3-phosphate dehydrogenase) conjugated with known amounts of biotin or BODIPY fluorophore.
- Quantification via Western blotting or fluorescence imaging on SDS-PAGE gels.
Main Results:
- Successful standardization of thiol-reactive probes for proteomic applications.
- Establishment of a reliable method for creating and utilizing external standards for quantification.
- Demonstrated ability to visualize and measure protein thiol modifications in biological samples with enhanced sensitivity.
Conclusions:
- The developed method provides a sensitive and quantitative approach for analyzing protein thiol modifications.
- The use of external standards facilitates accurate measurement of thiol modifications in complex biological samples.
- This protocol offers a valuable tool for researchers studying redox signaling and thiol chemistry.
