Lysine hydroxylation and O-glycosylation in the globular, C-terminal region of mammalian-expressed, recombinant PrP

► Recombinant, mammalian-expressed prion protein contains a modification in the C-terminal domain. ► Lys193 is converted to hydroxylysine with a disaccharide added to the new hydroxyl. ► Mass spectrometry and Edman degradation demonstrate the presence of the modification. ► Molecular dynamics indicates that lys193 glycans produce stabilisation of a critical loop of PrP.