Alterations of glycoprotein content and/or glycosylation degree, as well as change of glycan structure, are important factors in the development of many diseases. CD BioGlyco has focused on the development of quantitative methods for glycoproteins to provide scientific help for clients to explore the role of glycoproteins in the pathogenesis of related diseases.

Introduction

Quantitative glycoproteomics research has become a new hotspot at present. However, due to the intrinsic characteristics of glycoproteins, the relative quantification of glycoproteins faces serious challenges. The development of quantitative glycoproteomics methods and techniques will increasingly become an important tool for the biological functions research of glycoproteins. Although many bioinformatics tools are currently available for glycopeptide analysis, the mass spectrometric signature fragment ions required for complete structure determination are not available.

The mixtures of N- and O-linked glycopeptides and peptides obtained in protease digestions can be analyzed directly by LC-MS. Glycopeptides are characterized by tandem mass spectrometry, commonly referred to as "MS/MS" or "MSⁿ", and fragmented by appropriate dissociation techniques to obtain several key fragment characteristics of the entire glycopeptide structure. The thorough elucidation of the glycopeptide structure requires the simultaneous determination of amino acid sequence and exhaustive characterization of its carbohydrates, containing the attachment sites and the degree of site occupancy.

Fig.1 Schematic diagram of a glycoproteomics search engine, including inputs, outputs and intermediate steps. (Klein, 2019)

Quantification Strategies

CD BioGlyco provides a variety of technology platforms for quantitative analysis of glycoproteins at the protein level. The strategies we provide include but are not limited to:

• Glycopeptides or deglycosylated and labeled peptides can be analyzed directly by MS such as MALDI-TOF-MS or ESI-MS. In addition, peptides, glycopeptides, and labeled peptides can also be first separated by LC in LC-MS and then injected online into a high-resolution mass spectrometer for mass measurement of each component and its fragments.
• Proteins extracted from cells are digested with trypsin, enriched with lectin chromatography, labeled with TMT, and then quantified using LC-HCD-MS.
• Proteins extracted are digested followed by TMT10plex-labeled. Glycopeptides are enriched by a combination of hydrophilic interaction and titanium dioxide solid-phase extraction and quantified using LC-HCD-MS.

Advantages of Us

• Reliable and reproducible quantitative results
• Professional R&D team composed of doctors
• Technical consultant with extensive expertise
• Cost-effective and high-quality services

With the help of advanced experimental equipment and cutting-edge scientific research achievements, CD BioGlyco has established a variety of effective glycoprotein quantitative strategies, and our researchers will provide the best experimental scheme according to the needs of customers. If you are interested in our business, please contact us for more information.

Reference

1. Klein, J.A.; Zaia, J. A perspective on confident comparison of glycoprotein site-specific glycosylation in sample cohorts. Biochemistry. 2019, 59(34): 3089-3097.