The second binds a glycan to either serine (N-linked glycosylation) in the endoplasmic reticulum or threonine (O-linked glycosylation) within the Golgi apparatus. Glycoproteins are proteins which comprise oligosaccharide chains covalently attached to amino acid side-chains. The carbohydrate is attached to the protein in a cotranslational or posttranslational modification. The proteins which might be launched in...