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Updated: Jun 2, 2026
12:11
Simultaneous Affinity Enrichment of Two Post-Translational Modifications for Quantification and Site Localization
Published on: February 27, 2020
A "tag-and-modify" approach to site-selective protein modification.
Justin M Chalker1, Gonçalo J L Bernardes, Benjamin G Davis
1Department of Chemistry, University of Oxford, Chemistry Research Laboratory, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom.
Accounts of Chemical Research
|May 14, 2011
Summary
Protein chemists developed a "tag-and-modify" strategy for precise protein engineering. This approach uses chemical tags to enable selective covalent modifications, expanding protein functionality for biological studies.
Area of Science:
- Chemical Biology
- Synthetic Chemistry
- Protein Engineering
Background:
- Covalent modification expands protein function for imaging and isolation.
- Post-translational modifications regulate cellular processes.
- Site-specific chemical modifications are crucial for biological elucidation.
Purpose of the Study:
- To discuss the development and application of selective protein modification chemistry.
- To highlight the "tag-and-modify" strategy for protein engineering.
- To showcase advancements in bio-orthogonal chemistry for protein functionalization.
Main Methods:
- Utilized a "tag-and-modify" approach involving sequential installation and modification of chemical tags.
- Employed natural residues like cysteine and unnatural amino acids with azide, alkyne, or alkene groups.
- Adapted metal-catalyzed reactions (e.g., Cu-catalyzed azide-alkyne addition, Ru-catalyzed olefin metathesis) for protein modification in aqueous environments.
Main Results:
- Developed methods for stable thioether modifications via disulfide desulfurization and dehydroalanine conjugate addition.
- Demonstrated the versatility of the dehydroalanine tag for various modifications (phosphorylation, glycosylation, etc.).
- Successfully applied bio-orthogonal transformations to install multiple distinct modifications on protein surfaces.
Conclusions:
- Selective protein modification chemistry has advanced significantly through the "tag-and-modify" strategy.
- The development of novel catalysts and reagents enables precise protein engineering in biological settings.
- Synthetic access to modified proteins allows for unprecedented interrogation of biological systems.
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