This family contains N(G),N(G)-dimethylarginine dimethylaminohydrolases (DDAH) from eukaryotes. It also includes arginine deiminases and DDAH from prokaryotes. These enzymes are involved in arginine metabolism and belong to the amidinotransferase (AT) superfamily as they share the alpha/beta propeller fold, which includes structurally important residues (buried hydrophobic residues, buried hydrophilic residues hydrogen-bonded with mainchain groups and the hallmark of three consecutive buried Gly residues near the C-terminus, conserved among its members [1,2].

1: A novel superfamily of enzymes that catalyze the modification of guanidino groups. Shirai H, Blundell TL, Mizuguchi K; Trends Biochem Sci 2001;26:465-468. PMID:11504612

2: Prediction of the structure and function of AstA and AstB, the first two enzymes of the arginine succinyltransferase pathway of arginine catabolism. Shirai H, Mizuguchi K; FEBS Lett 2003;555:505-510. PMID:14675764