As a forward-looking company as well as a leading custom service provider in the field of glycoprotein analysis, Creative Biolabs has won a good reputation among worldwide customers. With our extensive experience and advanced platform, we have successfully accomplished numerous challenging glycan sequencing projects for glycoprotein structure analysis. We are glad to help you get milestone success in your glycoprotein project.
Glycan sequence is one of the main characters of glycopeptide, standing for the monosaccharide sequence and branching. Glycan sequencing can provide an indication of the structure, sequence, and branching of glycan chain, illuminating the protein’s glycosylation profile, microheterogeneity and its activity. Glycosylation has great importance in the development of biological drugs because their glycan chains markedly affect product stability, activity, antigenicity, and pharmacodynamics. Glycan sequences mainly contribute to glycan microheterogeneity.
Based on glycan ionization, fragmentation, and mass identification of the fragments, MS analysis is usually used for glycan sequencing. Electrospray ionization (ESI) MS/MS and matrix-assisted laser desorption/ionization (MALDI) MS/MS are two main MS methods for oligosaccharide analysis. Before analysis, the glycan sample must be desalted to prevent ionization masking in ESI and MALDI analysis and fragment ions obtained from permethylated derivatives are easily assignable to glycan sequences. Collision-induced dissociation (CID) is the most common method to form glycan fragmentation. High CID causes glycan cross-ring cleavages, providing data on the monosaccharide linkages; while low CID energy yields glycosidic cleavages, providing data on the monosaccharide sequence and branching. CID MS/MS scans can identify putative glycoforms associated with the same glycosylation site.
High-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD), normal-phase high-performance liquid chromatography (HPLC) and reverse-phase-HPLC (RP-HPLC) are the most widely used chromatographic methods for glycan separation. It is notable that HPAEC-PAD requires high-pH and high-salt buffers (which must be removed before further analysis of the separated glycans, such as in the case of exoglycosidase sequencing). NP-HPLC, having high resolution and reproducibility, is the most efficient method for glycan sequencing. RP-HPLC can analyze the resulting peptide and glycopeptides fragments after digestion of a glycoprotein with specific proteases after reduction and alkylation.
Technologies for glycan sequencing in Creative Biolabs including but not limited to the above methods.
Fig.1 Glycan sequencing of Man3 glycan and the related Man1 glycan (Both, 2014).
Creative Biolabs is a leader in the field of glycoprotein analysis and has successfully completed a lot of therapeutic glycoprotein projects. We have experienced experts and advanced platforms that can provide excellent services for glycan sequencing. We can offer a whole set of glycosylation sequencing service to help you get landmark development. We can also customize our offering to meet your specific project needs. If you are interested, please contact us without hesitation.