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Site-specific protein modification on living cells catalyzed by Sortase
Tsutomu Tanaka1, Teruyasu Yamamoto, Shinya Tsukiji
1Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo, 7-3-1, Hongo, Tokyo, 113-8656, Japan.
Chembiochem : a European Journal of Chemical Biology
|February 26, 2008
Summary
Researchers developed a new method for precisely modifying proteins on living cells using Sortase enzymes. This technique enables site-specific labeling and conjugation of cell surface proteins, advancing cell biology and engineering.
Area of Science:
- Biochemistry
- Molecular Biology
- Cell Biology
Background:
- Enzymatic modification offers precise control for altering proteins on living cells.
- Sortase, a transpeptidase from Staphylococcus aureus, facilitates site-specific peptide ligation.
Purpose of the Study:
- To establish a general strategy for site-specific modification of cell surface proteins using Sortase.
- To demonstrate the utility of this method for labeling and protein-protein conjugation on living cells.
Main Methods:
- Genetically introducing an LPETGG peptide tag to the C terminus of target cell surface proteins.
- Utilizing Sortase and a triglycine-containing probe for site-specific labeling.
- Applying the method to label osteoclast differentiation factor (ODF) with biotin or fluorophores.
Main Results:
- Successful C-terminal-specific labeling of ODF on living cells.
- Efficient labeling in various media (serum-containing, serum-free, PBS) within 5 minutes.
- Demonstrated site-specific protein-protein conjugation on living cell surfaces via Sortase.
Conclusions:
- The Sortase-based strategy provides a powerful and efficient tool for site-specific cell surface protein modification.
- This method has significant implications for advancing cell biology research and cell surface engineering applications.
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