has part has role is deprotonated form of is protonated form of is tautomer of serine serine An α-amino acid that is alanine substituted at position 3 by a hydroxy group. Serine 2-amino-3-hydroxypropanoic acid Serine CHEBI:15081 3-Hydroxyalanine CHEBI:26648 CHEBI:9116 2-Amino-3-hydroxypropionic acid serine Serin hydroxymethyl group polar amino acid serinate serinium alpha-amino acid serine zwitterion fundamental metabolite