This family includes arginase, also known as arginase-like amidino hydrolase family, as well as arginase-like proteins and are found in bacteria, archaea and eykaryotes, but does not include metazoan arginases. Arginase is a binuclear Mn-dependent metalloenzyme and catalyzes hydrolysis of L-arginine to L-ornithine and urea (Arg, EC 3.5.3.1), the reaction being the fifth and final step in the urea cycle, providing the path for the disposal of nitrogenous compounds. Arginase controls cellular levels of arginine and ornithine which are involved in protein biosynthesis, and in production of creatine, polyamines, proline and nitric acid.
Comment:Active site is composed of the metal binding (Mn), water and substrate binding (arginine) site.
Comment:Two Mn2+ ions are located in the active site. A The bridging water symmetrically positioned between them is responsible for hydrolytic attack on the guanidine group of the substrate.
Jiyao W et al.(2023). "The conserved domain database in 2023.",