O-glycosyl-L-threonine Hex1HexNAc1NeuAc1 glycosylated residue Hex1HexNAc1NeuAc1 O-glycosylated threonine 657.23541259765625 657.5999755859375 758.28314208984375 758.70001220703125 A protein modification that effectively replaces an O3 hydrogen atom of a threonine residue with a carbohydrate-like group composed of Hex1HexNAc1NeuAc1 linked through a glycosidic bond. C 25 H 41 N 2 O 18 C 29 H 48 N 3 O 20 Hex(1)HexNAc(1)NeuAc(1) Hex1HexNAc1NeuAc1 MOD:01355 PSI-MOD T Unimod:149 natural