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Updated: Jun 21, 2026
12:06
Metabolic Glycoengineering of Sialic Acid Using N-acyl-modified Mannosamines
Published on: November 25, 2017
Metabolic glycoengineering: sialic acid and beyond.
Jian Du1, M Adam Meledeo, Zhiyun Wang
1Department of Biomedical Engineering, The Johns Hopkins University, Baltimore, MD 21218, USA.
Glycobiology
|August 14, 2009
Summary
Metabolic glycoengineering enables replacing natural sialic acids with synthetic variants in cells and animals. This versatile technology offers new tools for glycoscientists to control biological systems through glycan modification.
Area of Science:
- Glycoscience
- Chemical Biology
- Biotechnology
Background:
- Sialic acids are crucial components of cell surface glycans.
- Natural control over sialic acid chemistry in biological systems is complex.
- Existing methods lack the precision to engineer specific glycan structures.
Purpose of the Study:
- To provide a perspective on metabolic glycoengineering over the past two decades.
- To highlight the use of chemical variants to replace natural sialic acids.
- To demonstrate the potential of this technology in mimicking natural biological control.
Main Methods:
- Metabolic substrates (e.g., ManNAc, Neu5Ac analogs) are used to modify the sialic acid biosynthetic pathway.
- Bioorthogonal chemoselective ligation reactions are employed to functionalize modified glycans.
- Methodology has been extended to GalNAc, fucose, and O-GlcNAc pathways.
Main Results:
- Nonnatural sialoside display on cellular glycans leads to diverse biological outcomes.
- Engineered glycans can be functionalized with various ligands, enhancing versatility.
- Analog incorporation is now possible in multiple glycan types and proteins.
Conclusions:
- Metabolic glycoengineering provides powerful chemical tools for glycoscientists.
- The technology allows for the precise manipulation of cell surface glycans.
- Further development is enhancing the application of glycoengineering in biological research and therapeutics.
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