H2O + N(2)-acetyl-L-ornithine = acetate + L-ornithine Binds 2 Zn(2+) or Co(2+) ions per subunit. Amino-acid biosynthesis; L-arginine biosynthesis; L-ornithine from N(2)-acetyl-L-ornithine (linear): step 1/1. Homodimer. A number of isoforms are produced. According to EST sequences. Belongs to the peptidase M20A family. ArgE subfamily. Truncated N-terminus.