The key difference between N-linked and O-linked glycosylation is:
Two major enzymatic glycosylation systems differ fundamentally in linkage chemistry, sugar identity at attachment point, donor substrate and cellular location. N-linked glycosylation forms amide linkage between N-acetylglucosamine GlcNAc β-linked to side chain nitrogen of asparagine within consensus Asn-X-Ser/Thr where X not proline, initiated co-translationally in ER by oligosaccharyltransferase complex using dolichol-linked precursor Glc3Man9GlcNAc2 assembled on lipid carrier. Subsequent trimming and Golgi processing generate high-mannose, hybrid and complex types influencing folding and sta
Ref: Stanley et al., Essentials of Glycobiology, 4th ed., Chapter 9: N versus O Glycosylation.
