Functions of N-glycan

The surface of every cell in our body is covered with dense sugar molecules that are key mediators of cell-cell, cell-ligand, and cell-pathogen interactions. Glycans are one of the major components of cells and play a key role in many physiological processes in the body (e.g., growth and development of the body and occurrence of diseases, etc.). Glycans on the cell surface are structurally rich and diverse. However, when the human body generates physiological activities, cell surface N-glycans produce changes in structure or expression, and thus cell surface N-glycans can be applied as an important marker for disease diagnosis. To deeply explore the physiological roles of glycans, it is necessary to apply Glycoengineering Techniques to determine their structures and complete sequences and to understand the information encoded in these glycan molecules and the mechanisms by which they facilitate protein-protein interactions.

Fig.1 Detection of cell surface glycans. (Nischan & Kohler, 2016)

Cell Surface Lewis Type N-glycan Glycoengineering Service at CD BioGlyco

A cell surface Lewis-type N-glycan is an N-linked glycan chain that contains one or more Lewis acid residues. Lewis-type N-glycans have important roles in biology, so their analysis and characterization are an important direction in glycomics.

We utilize a universal three-module technology for photo-controlled scarless selective glycan chain editing for chemical modification and editing of cell surface Lewis-type N-glycans at the protein-specific level. First, a Lewis-type N-glycan processing enzyme is specifically coupled to the protein to form a ligand-glycanase affix. Next, the protein of interest is targeted by ligand-receptor interactions while the glycanase is stationed on the protein to perform glycan editing events. Finally, chemical modification and editing of the N-glycan is accomplished.

In addition, at CD BioGlyco, we provide Lewis-type N-glycans structural analysis, sequence determination, and exploration of the physiological functions services by a Glycoengineering Platform.

• Cell surface Lewis-type N-glycans synthesis
  
  • One strategy for mounting synthetic glycans on the cell surface is to attach them to membrane proteins through selective chemical reactions. Cell surface synthesis of Lewis-type N-glycans can be used to study the effects of specific glycan structures on cell differentiation and behavior.
  • A second strategy is to introduce chemical reporter genes into cellular glycans. These chemical reporter genes can in turn be reacted with fluorescent labeling or affinity probes to enable the detection, imaging, and purification of specific N-glycans.
• Glycan chain structure and sequence determination
  We offer enzyme cleavage and mass spectrometry (MS) to analyze the sequence of Lewis-type N-glycan glycan chains and the type and structure of intra-chain linkages.
• Exploring N-glycan expression
  Approaches to N-glycan expression are valuable tools for understanding and regulating the biological functions of cell surface glycoconjugates. At CD BioGlyco, we will employ controlled glycosyltransferase genes to control N-glycan expression.

Fig.2 Cell surface Lewis-type N-glycans glycoengineering services. (CD BioGlyco)

Publication

Paper Title: Enzymatic sequence analysis of N-glycans by exoglycosidase cleavage and mass spectrometry: detection of Lewis X structures.

Technology: Enzymatic and mass spectrometric sequencing of glycans

Journal: Methods in Molecular Biology

Published: 2019

Results: In this study, the authors describe enzyme sequence analysis applied to a mixture of acid glycoproteins released from α1-glycans. Possible Lewis X structures after exoglycosidase digestion were detected stepwise by MALDI-TOF mass spectrometry. In addition, other structural properties of the N-glycans were determined by using the respective specific extracellular glycosidases.

Fig.3 MALDI-TOF mass spectrometry of N-glycans released from an α1-acid glycoprotein and treated with different glycosidases. (Kannicht, et al., 2019)

Applications

• Glycoengineering techniques can be applied to study physiological activities generated in animals. For example, they are involved in cell adhesion, signaling, and immune regulation.
• Lewis-type N-glycans glycoengineering services can be applied to produce cell surface glycans.
• In biology, glycoengineering techniques can be applied to explore the functions that cell surface glycans have.

Highlights

• Our specialized glycoengineering techniques help our clients to precisely understand the functions mediated by carbohydrates.
• We develop research programs that are highly selective, extensive, and comprehensive.

CD BioGlyco has specialized in cell surface glycoengineering techniques and has developed a complete cell surface glycoengineering platform. We have services such as synthesis of Lewis-type N-glycans, structure and sequence analysis, and exploration of their expression. If you are interested in our services, please contact us for more details.