Protein glycosylation is a process whereby oligosaccharides covalently bind to specific amino acid residues on proteins in the form of glycosides. Protein glycosylation can be divided into four categories based on the connection method between the amino acid and the sugar: O-linked glycosylation, N-linked glycosylation, C-mannosylation, and glycosylphosphatidylinositol (GPI)-anchoring....