Threonine proteases use the hydroxyl group of the amino acid of their catalysis and it's a precursor in a single biosynthetic pathway for making glycine. The 9 amino acids that belong to this group are: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine In case you adored this article along with you wish to a...