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Updated: Jul 5, 2026
11:25
Targeting Cysteine Thiols for in Vitro Site-specific Glycosylation of Recombinant Proteins
Published on: October 4, 2017
Modification of cysteine
1Washington University School of Medicine, St. Louis, Missouri, USA.
Current Protocols in Protein Science
|April 23, 2008
Summary
This study details various methods for modifying cysteine residues in proteins and peptides using reduction and alkylation techniques. These protocols offer flexibility for different protein amounts and known/unknown compositions, aiding in protein analysis.
Area of Science:
- Biochemistry
- Protein Chemistry
- Analytical Chemistry
Background:
- Cysteine residues are crucial for protein structure and function.
- Modifying cysteine residues is essential for various analytical techniques.
- Existing methods may have limitations regarding protein quantity or prior knowledge of composition.
Purpose of the Study:
- To describe diverse methods for cysteine residue modification in proteins and peptides.
- To provide protocols applicable to proteins of known and unknown size/composition.
- To detail techniques for cysteine modification relevant to protein sequencing and analysis.
Main Methods:
- Reduction and alkylation procedures using reagents like haloacyl compounds and N-ethylmaleimide (NEM).
- Specialized alkylation protocols for limited protein amounts and for introducing amino groups.
- Methods for sequence analysis, including alkylation with 4-vinylpyridine and acrylamide, and reversible modification via sulfitolysis.
- Oxidation protocols for amino acid analysis and disulfide formation.
Main Results:
- A comprehensive set of protocols for cysteine modification is presented.
- Methods are adaptable for varying protein quantities and compositions.
- Specific procedures are outlined for protein sequencing and analysis.
Conclusions:
- The described methods provide a versatile toolkit for cysteine residue modification.
- These techniques support various downstream applications in protein research.
- The protocols enhance the ability to analyze and characterize proteins and peptides.
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