Carbamoyl phosphate synthetase

Carbamoyl phosphate synthetase is an enzyme that catalyzes a reaction that produces carbamoyl phosphate. This enzyme catalyzes the reaction of ATP and bicarbonate to produce carbonyl phosphate and ADP. Carbonyl phosphate reacts with ammonia to give carbamate. In turn, carbamate reacts with a second ATP to give carbamoyl phosphate plus ADP.

There are two different forms that serve very different functions:
 * Carbamoyl phosphate synthetase I (mitochondria, urea cycle)
 * Carbamoyl phosphate synthetase II (cytosol, pyrimidine metabolism).