Carbamoyl phosphate synthetase I

Carbamoyl Phosphate Synthetase I is a ligase enzyme located in the mitochondria involved in the production of urea. Carbamoyl phosphate synthetase I (CPS1 or CPSI) transfers an ammonia molecule from glutamine or glutamate to a molecule of bicarbonate that has been phosphorylated by a molecule of ATP. The resulting carbamate is then phosphorylated with another molecule of ATP. The resulting molecule of carbamoyl phosphate leaves the enzyme.