N-linked Glycosylation Attachment

N-linked glycosylation is a crucial co-translational and post-translational modification process where oligosaccharide chains are attached to proteins.

The defining feature of N-linked glycosylation is the specific linkage formed:

• The oligosaccharide is attached via the side chain amide nitrogen atom of an asparagine (Asn) residue.
• This attachment occurs within a specific consensus sequence motif, typically Asn-X-Ser or Asn-X-Thr, where X can be any amino acid except proline.

Therefore, the oligosaccharide chain is attached to the protein by asparagine.

Note: Serine and threonine residues are involved in O-linked glycosylation, where the attachment is to the hydroxyl group of the side chain.