Cytidine Triphosphate (CTP)

CTP is a ribonucleotide used in synthesis of several compounds, including RNA, and several glycerophospholipids. It allosterically inhibits the enzymes aspartate transcarbamoylase, and CTP synthetase (see below), which are both involved in nucleotide metabolism.

1. Phosphocholine + CTP <=> CDP-choline + PPi, (catalyzed by CTP:phosphocholine cytidyl transferase)

2. Phosphatidic Acid + CTP <=> CDP-Diacylglycerol + PPi

3. CDP + ATP <=> CTP + ADP (catalyzed by Nucleoside Diphosphokinase)

4. UTP + ATP + Gln <=> CTP + ADP + Glu + Pi (catalyzed by CTP Synthetase)

CTP is an allosteric inhibitor of glutamine synthetase, an enzyme with a central role in nitrogen metabolism in the cell.

See also: Cytosine, RNA