Periodate Oxidation-based Cell Surface Glycoengineering Service at CD BioGlyco

Cell surface glycans are a rich source of information reporting the physiological status of cells and reflect the activities of cell-to-cell, cell-to-ligand, and cell-to-pathogen secretion mechanisms. Direct cell behavior by modifying and engineering glycans on the cell surface. Genetic approaches to manipulate glycosyltransferase genes are a useful approach to control glycan expression, and chemical strategies for glycoengineering provide a valuable complement to genetic approaches. At CD BioGlyco, we have developed a Cell Surface Glycoengineering platform to introduce unnatural functionality (e.g., fluorophores) into cell surface glycans through biochemical and chemical strategies. It provides unique opportunities for studying cell surface glycan function.

Chemical or enzymatic oxidation of specific carbohydrate residues is an early development and still used strategy for the covalent labeling and enrichment of cell surface glycans. This method is used to label sialic acid or galactose- or N-acetylgalactosamine (GalNAc)-containing glycans on the cell surface. These glycans display a cis-diol motif that is oxidatively cleaved to aldehydes by chemical reagents such as sodium periodate. The resulting aldehyde intermediates are further conjugated to the desired reporter group with an amine nucleophile (e.g., hydrazine or aminooxy reagent). At the same time, we also add aniline catalysts to the reaction to improve labeling efficiency.

• Mild Periodate Oxidation

Mild periodate oxidation is used to selectively label sialylated N- and O-glycans.

• Strict Periodate Oxidation

Rigorous periodate oxidation applies to trans-diol glycans such as N-acetylglucosamine (GlcNAc).

Fig.1 Periodate oxidation-based cell surface glycoengineering service. (CD BioGlyco)

Publication

Paper Title: High-efficiency labeling of glycoproteins on living cells

Technology: Chemical strategies for glycoengineering

Journal: Scientific Reports

IF: 48.0

Published: 2009

Results: In this study, mild periodate (1 mM NaIO₄, 4°C, 30 min) was used to introduce aldehydes to the C-7 position of sialic acid on the cell surface. It is then reacted with 100 µM aminooxybiotin under the catalysis of aniline for metabolic labeling. The study found that cells that were oxidized with NaIO₄ showed a 1,000-fold increase in biotinylation compared to cells that were not oxidized with NaIO₄. Catalysis by aniline also significantly enhanced the biotinylation of cell surface glycans.

Fig.2 Scheme for aminooxy-biotin labeling on cell surface sialic acids. (Zeng, et al., 2009)

Applications

• Use periodate to oxidize the monosaccharide of cis-diol to generate aldehyde, which is then reacted with an amine-functionalized reporter group to label specific monosaccharide residues on the cell surface.
• Cell surface glycans are used as a biomarker to detect the occurrence and development of cancer. Specific fluorescent tags or affinity probes are introduced onto cell surface glycans through periodate oxidation to achieve detection, imaging, and purification of glycoconjugate groups.
• The diversity and complexity of glycans make studying glycan function in normal and cancer cells challenging. Cell surface glycoengineering technologies have driven the rapid development of glycomics and glycoproteomics and provided complementary information sets for the study of glycans.

Advantages of Us

• We use a mild periodate method under aniline catalysis to selectively label glycans on the cell surface. This method effectively labels glycans on almost any living cell surface and maintains high cell viability.
• This method introduces any functional tag carrying an amine nucleophile into the cell surface.
• Our cell surface glycoengineering services enable visualization, monitoring, and tracking of cell surface glycoproteins.

CD BioGlyco provides custom cell surface glycoengineering services with a variety of Technologies to choose from for a wide range of biomedical research. Please feel free to contact us for more information on cell surface glycoengineering services.