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Updated: Jun 28, 2026
10:59
Enrichment of Bacterial Lipoproteins and Preparation of N-terminal Lipopeptides for Structural Determination by Mass Spectrometry
Published on: May 21, 2018
Lipid modification of proteins through sortase-catalyzed transpeptidation
John M Antos1, Gwenn M Miller, Gijsbert M Grotenbreg
1Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge, Massachusetts 02142, USA.
Journal of the American Chemical Society
|November 8, 2008
Summary
Researchers developed a chemoenzymatic method to attach lipids to proteins using Sortase A. This technique efficiently creates lipoproteins that associate with mammalian cells, localizing to membranes and endosomes.
Area of Science:
- Biochemistry
- Chemical Biology
- Protein Engineering
Background:
- Lipidation is crucial for protein function and localization.
- Existing methods for site-specific lipidation are often complex or inefficient.
Purpose of the Study:
- To develop a general and efficient chemoenzymatic method for site-specific protein lipidation.
- To create functional lipoproteins for cellular studies.
Main Methods:
- Utilized Sortase A enzyme for site-specific ligation.
- Appended lipid-modified oligoglycine peptides to protein C-termini.
- Developed a method for Sortase A enzyme removal post-ligation.
Main Results:
- Achieved excellent yields (60-90%) for various hydrophobic modifications.
- Successfully prepared lipoproteins using the described chemoenzymatic approach.
- Demonstrated lipid tail-dependent association of lipoproteins with mammalian cells.
Conclusions:
- The developed chemoenzymatic method provides a versatile platform for protein lipidation.
- The resulting lipoproteins effectively associate with and localize within mammalian cells.
- This technique facilitates the study of lipoprotein-protein interactions and cellular localization.
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