What Does Atp Atcase Do

ATP is an allosteric activator of ATCase, able to increase the activity of the enzyme by 180% at a 2 mM concentration35. ATP does not affect the maximal rate of the enzyme; instead, it induces a shift from the inactive T state to the active R state.

What kind of inhibitor is ATCase?

This inhibition by CTP is an example of feedback inhibition. ATCase is a textbook example of a molecule under allosteric regulation in which the binding of substrate to one active site in a molecule increases the likelihood that the enzyme will bind more substrate, a phenomena called cooperativity.

Where does ATP bind on ATCase?

The allosteric site in the allosteric domain of the R chains of the ATCase complex binds to the nucleotides ATP, CTP and/or UTP. There is one site with high affinity for ATP and CTP and one with 10- to 20-fold lower affinity for these nucleotides in each regulatory dimer.