obsolete protein glycosylation https://github.com/geneontology/go-ontology/issues/29770 https://github.com/geneontology/go-ontology/issues/30371 true GO:0006486 The reason for obsoletion is that this term represents a molecular function. OBSOLETE. A protein modification process that results in the addition of a carbohydrate or carbohydrate derivative unit to a protein amino acid, e.g. the addition of glycan chains to proteins. protein amino acid glycosylation GO:0065006 glycoprotein biosynthetic process