Relative quantification of glycoproteins is a challenging task and is under steadily increasing demand, but only a few laboratories have the expertise required to accomplish this task. CD BioGlyco is aimed at researchers in the fields of molecular biology and biochemistry, providing reliable tools for quantifying glycoproteins at the glycosylation occupancy level.

Quantitative Glycoproteomics Strategies

The disadvantage of the glycomics approach is that when glycans are released from proteins, site-specific information including attachment sites and occupancy rates is lost. However, in glycoproteomics approaches, glycan release is not required and the glycan-peptide bonds are kept intact to obtain information of glycosylation sites and site occupancy. Currently, a variety of reliable and sensitive quantitative glycoproteomics strategies have been described, many of which have been used to quantitatively assess glycoprotein changes associated with the development and progression of many diseases. These strategies have enabled a better study of the biological properties of complex glycosylation mechanisms in biological systems.

Glycoproteomics analysis is composed of two complementary workflows: glycosylation site analysis and glycopeptide analysis. Site mapping is normally performed first, which can reveal occupied potential glycosylation sites. This information is valuable for data analysis in the subsequent analysis of glycopeptide. Since deducing glycosylation site occupancy from intact glycopeptides is challenging, especially with the lack of peptide fragment information during MS/MS, researchers often analyze deglycosylated peptides or partially deglycosylated peptides to obtain site-specific information.

Fig.1 An example MS/MS-HCD spectrum of a glycopeptide carrying a high-mannose type N-glycan, Man5GlcNAc2 on asparagine. (Shajahan, 2017)

Our Strategies

CD BioGlyco has established time-tested and robust quantitative glycoproteomics methods to provide our clients with reliable data on glycosylation occupancy. Our strategies include but are not limited to:

• We have developed new analytical tools to quantify glycosylation occupancy through enriching glycoproteins, labeling glycosylated asparagines using endoglycosidase H glycan release, and detecting peptides and glycopeptides using LC-ESI-MS/MS.
• We have established methods that combine enzymatic deglycosylation and protease digestion with SWATH-MS to automatically measure site-specific occupancy at many glycosylation sites.
• Glycopeptide analysis. A variety of tandem mass spectrometry methods, such as high-energy collisional dissociation (HCD), collision-induced dissociation (CID), or electron transfer dissociation (ETD) are used to determine the detailed characterization of carbohydrates, including attachment sites and site occupancy.

Applications

• Characterization of glycoproteins from enriched samples
• Understanding sources of error in glycopeptide assignments
• Research on the biological attribute of complex glycosylation mechanisms

Advantages of Us

• Accurate and reproducible glycoproteomics data
• Cutting-edge experimental platform
• Frontier expertise
• Specialized technical guidance

CD BioGlyco is a biotech company specializing in glycomics and glycoproteomics and has a good reputation in the industry for providing a trusted service. If you require further consultation, please contact us directly.

Reference

1. Shajahan, A.; et al. Glycomic and glycoproteomic analysis of glycoproteins-a tutorial. Anal Bioanal Chem. 2017, 409, 4483–4505.