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Updated: Aug 27, 2025
07:16
Resin-Assisted Capture Coupled with Isobaric Tandem Mass Tag Labeling for Multiplexed Quantification of Protein Thiol Oxidation
Published on: June 21, 2021
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A rapid and selective methionine oxidative modification strategy.
Meng-Qian Zhang1, Pei-Yang He1, Jin-Jian Hu1
1Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Department of Chemistry, Tsinghua University, Beijing, China.
Summary
Chemists developed a fast, selective method to modify methionine, an oxidation-sensitive amino acid. This new technique efficiently creates sulfoximine-modified peptides, expanding peptide functionalization options.
Area of Science:
- Biochemistry
- Organic Chemistry
- Chemical Biology
Background:
- Site-selective late-stage diversification of peptides and proteins is a significant challenge.
- Strategies for modifying low-abundance natural amino acids require further development.
- Methionine, an oxidation-sensitive and low-abundance amino acid, presents a promising target for selective modification.
Purpose of the Study:
- To develop an efficient and highly selective method for modifying methionine residues in peptides.
- To expand the toolbox for methionine-based peptide functionalization.
Main Methods:
- A one-pot O- and N-transfer reaction was employed for peptide modification.
- The reaction targets methionine residues for chemo- and site-selective modification.
- Various peptide substrates were used to demonstrate the protocol's generality and tolerance.
Main Results:
- Near-perfect conversion of methionine residues to sulfoximine-modified peptides was achieved within 10 minutes.
- The reaction demonstrated high tolerance to other natural amino acids present in the peptide substrates.
- Natural peptides were successfully modified, yielding sulfoximination products with high conversion rates.
Conclusions:
- A novel, efficient, and highly selective method for sulfoximination of methionine residues in peptides has been established.
- This methodology offers a valuable new strategy for peptide functionalization.
- The developed protocol expands the capabilities for modifying peptides at specific sites, particularly targeting methionine.
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