O-Glycosylation plays an important role in many biological processes. CD BioGlyco provides clients with high-affinity and specific enrichment services for O-glycoproteins and peptides.
Proteins are direct biological function molecules in nerve cells and play an important role in the central nervous system. Glycosylation is a universal co-translational and post-translational modification (PTM) that exists in almost all areas of life. The two most common types of glycosylation are 1) N-glycans covalently attached to Asp residues of proteins; 2) O-glycans covalently attached to Ser/Thr residues of proteins. Glycosylation is closely related to many biological functions of the central nervous system. It is generally heterogeneous and mass spectrometry (MS) captures varying degrees of heterogeneity within these glycosylation classes. But the presence of glycoforms and the chemical nature of glycoproteins relative to unmodified proteins make glycoproteins less abundant. Therefore, it is very necessary to enrich glycoproteins or glycopeptides to separate glycoconjugates from non-glycosylated background species before MS analysis.
Numerous methods of enrichment for glycosylation have been reported, including 1) enrichment for glycan affinity by glycan-binding proteins or charged moieties; 2) enrichment by chemical properties such as charge or hydrophilicity; 3) chemical coupling of glycans to stationary phases; 3) Various chemical biology methods combined with bioorthogonal handles. For example, glycosidase is an enzyme that hydrolyzes sugar chains and is used for the characterization of glycoproteins. The most widely used glycosidase is peptide-N-glycosidase F (PNGaseF), which is used to hydrolyze the glycosidic bond between N-acetylglucosamine (GlcNAc) and Asp residues. Then it releases high mannose, complex N-glycans, and hybrid N-glycans.
Fig.1 A summary of glycosylation enrichment strategies. (Riley, et al., 2021)
O-linked glycans are involved in various biological processes such as inflammation and cell signaling. During MS analysis, glycoprotein or glycopeptide enrichment is required before analysis due to the low content of O-glycoprotein and the presence of micro-heterogeneity. At CD BioGlyco, we have developed a well-established Glycoprotein Enrichment strategy. Our strategy enables high-affinity enrichment and purification of proteins and peptides carrying O-glycans by specific glycosidases. O-Glycoproteins and peptides in the samples are then quantified by highly sensitive and selective MS techniques. Our enrichment protocol is applied not only to the specific enrichment of O-glycosylated proteins and peptides but also to the analysis of O-linked glycomics and the characterization of O-glycosylated biopharmaceuticals.
CD BioGlyco specializes in Glycoproteomic research and has been recognized by scientists from many countries. We are willing to share our knowledge and experience in this field. If you are interested in our O-glycoproteins and peptides enrichment, please contact us for more details without any hesitation.