has part has role is deprotonated form of is protonated form of branched-chain amino acid valine valine Valin valina 2-amino-3-methylbutanoic acid Hval valine A branched-chain amino acid that consists of glycine in which one of the hydrogens attached to the α-carbon is substituted by an isopropyl group. DL-valine isopropyl group valinate valinium alpha-amino acid plant metabolite Daphnia magna metabolite