Carbamoyl phosphate synthetase (glutamine-hydrolysing) () is an enzyme that catalyzes the reactions that produce carbamoyl phosphate in the cytosol (as opposed to type I, which functions in the mitochondria). Its systemic name is hydrogen-carbonate:L-glutamine amido-ligase (ADP-forming, carbamate-phosphorylating).
In pyrimidine biosynthesis, it serves as the rate-limiting enzyme and catalyzes the following reaction:
It is activated by ATP and PRPP and it is inhibited by UTP (Uridine triphosphate) Neither CPSI nor CPSII require biotin as a coenzyme, as seen with most carboxylation reactions.
It is one of the four functional enzymatic domains coded by the CAD gene. The CAD gene is a large gene. It uses a single strand to code for these enzyme jobs. It is classified under .