Carbamoyl phosphate is an intermediate in arginine,
urea, and pyrimidine
biosynthesis. Carbamoyl phosphate is created in
reactions 1 and 2 below.
1. NH4+ + CO2 + 2 ATP <=> Carbamoyl Phosphate + 2 ADP + Pi (catalyzed Carbamoyl Phosphate Synthetase)
2. Glutamine + ATP + HCO3- <=> Glutamate + Carbamoyl phosphate + ADP (catalyzed by Carbamoyl Phosphate Synthetase II)
3. Carbamoyl phosphate + Ornithine <=> Citrulline + Pi (catalyzed by Ornithine Transcarbamoylase)
4. Aspartate + Carbamoyl Phosphate <=> Carbamoyl aspartate (catalyzed by Aspartate Transcarbamoylase)
Carbamoyl phosphate is an allosteric inhibitor of glutamine synthetase, an enzyme with a central role in nitrogen metabolism in the cells.
INTERNET LINK: Urea
Cycle and Metabolism of Amino Groups