Cytidine triphosphate

Cytidine 5′-triphosphate (CTP) is a pyrimidine nucleoside triphosphate that is analogous to the better-known ATP, but with cytidine as the base instead of adenine. It is a substrate in the biosynthesis of RNA.

Triphosphates like CTP and ATP are high-energy molecules; but ATP is involved in many more metabolic reactions than CTP. Now, however, CTP may be useful in the development of new antiviral drugs.

The research groups of biochemists Steven C. Almo at the Albert Einstein College of Medicine (Bronx, NY) and Craig Cameron at Penn State (University Park, PA) discovered that an enzyme expressed in humans catalyzes the dehydration of CTP to produce another triphosphate abbreviated as ddhCTP. The dehydrated species resembles current antivirals that disrupt RNA genome replication in some viruses.

In in vitro experiments, the researchers found that ddhCTP inhibits RNA polymerases in viruses such as Zika, West Nile, dengue, and hepatitis C. In addition to the possibility of developing new antivirals by using this technique, experts predict that this research could open new pathways to drugs based on natural small molecules.