What is "citrullinase"

In enzymology, a citrullinase is an enzyme that catalyzes the chemical reaction

L-citrulline + HO $\rightleftharpoons$ L-ornithine + CO + NH

Thus, the two substrates of this enzyme are L-citrulline and HO, whereas its 3 products are L-ornithine, CO, and NH.

This enzyme belongs to the family of hydrolases, those acting on carbon-nitrogen bonds other than peptide bonds, specifically in linear amides. The systematic name of this enzyme class is L-citrulline N5-carbamoyldihydrolase. Other names in common use include citrulline ureidase, citrulline hydrolase, and L-citrulline 5-N-carbamoyldihydrolase.