Quantitative characterization of O-GalNAc glycosylation

O-GalNAc type glycosylation is an abundant and complex protein modification. Recent developments in mass spectrometry resulted in significant success in quantitative analysis of O-GalNAc glycosylation. The analysis of released OGalNAc type glycans expanded our horizons of understanding the glycome of various biological models. The site-specific analysis of glycosylation micro-heterogeneity of purified proteins opened perspectives for the improved design of glycoprotein therapeutics. Advanced gene editing and chemical technologies applied to O-glycoproteomics enabled to identify O-GalNAc glycosylation at unprecedented depth. Progress in the analysis of intact glycoproteins under native and reduced conditions enabled the monitoring of glycosylation proteoform variants. Despite of the astonishing results in quantitative O-GalNAc glycoproteomics, site-specific mapping of the full O-GalNAc structural repertoire in complex samples is yet a long way off. Here, we summarize the most common quantitative strategies in O-GalNAc glycoproteomics, review recent progress and discuss benefits and limitations of the various approaches in the field.

Automated summary

O-GalNAc type glycosylation is a complex and abundant protein modification, with recent advancements in mass spectrometry allowing for significant progress in quantitative analysis. Utilizing advanced gene editing and chemical technologies in O-glycoproteomics has enabled the identification of O-GalNAc glycosylation at unprecedented depth. Despite the impressive results in quantitative O-GalNAc glycoproteomics, the site-specific mapping of full O-GalNAc structural repertoire in complex samples remains a challenge.