Hydrolysis of urea to ammonia and CO(2). ATP + hydrogencarbonate + urea = ADP + H(+) + phosphate + urea-1-carboxylate 3 H(+) + H2O + urea-1-carboxylate = 2 CO2 + 2 NH4(+) Nitrogen metabolism; urea degradation; CO(2) and NH(3) from urea (allophanate route): step 1/2. Nitrogen metabolism; urea degradation; CO(2) and NH(3) from urea (allophanate route): step 2/2. Monomer. By allophanate or its non-metabolized analog oxalurate. Repressed in the presence of readily used nitrogen sources. Present with 952 molecules/cell in log phase SD medium.