Fig. 3.

Altered glycoproteome in COVID-19 patients. A. Altered glycosylation frequency of major N-glycosylated sites. Different types of glycans were merged. B. Altered glycosylation frequency of major N-glycans in major N-glycosylated sites. C. Reduced O-glycosylated peptide abundance of FCGBP, IGHA1, and IGHA2. The identifier of glycopeptide (left panel) is presented using the format: gene name_modification site_glycan_peptide sequence (the modification sites are highlighted in red). The protein abundance is shown in the corresponding right panel (Wilcoxon's rank sum test, ∗q < 0.05, ∗∗q < 0.01, ns, not significant). (For interpretation of the references to color in this figure legend, the reader is referred to the Web version of this article.)