N-linked glycosylation

N-linked glycosylation is the attachment of an oligosaccharide, a carbohydrate consisting of several sugar molecules, sometimes also referred to as glycan, to a nitrogen atom (the amide nitrogen of an asparagine (Asn) residue of a protein), in a process called N-glycosylation, studied in biochemistry.^[1] The resulting protein is called an N-linked glycan, or simply an N-glycan.

This type of linkage is important for both the structure^[2] and function^[3] of many eukaryotic proteins. The N-linked glycosylation process occurs in eukaryotes and widely in archaea, but very rarely in bacteria. The nature of N-linked glycans attached to a glycoprotein is determined by the protein and the cell in which it is expressed.^[4] It also varies across species. Different species synthesize different types of N-linked glycan.