protein O-linked glycosylation protein O-linked glycosylation via N-acetylglucosamine https://github.com/geneontology/go-ontology/issues/32044 biological_process 2026-05-07T16:32:08Z GO:7770074 protein O-linked GlcNAcylation sjm protein O-linked N-acetylglucosaminylation A glycoprotein biosynthetic process in which a single N-acetylglucosamine is covalently linked via a beta-glycosidic bond to the oxygen atom of a serine or threonine side chain in a protein, resulting in the formation of a protein O-linked glycan. The sugar is not elongated into a larger oligosaccharide chain.