The removal of that phosphoryl group from that enzyme is catalyzed by a different enzyme known as protein Phosphotase. And we'll discuss this protein in much more detail in a future lecture. So we essentially have the enzyme and the ATP molecule. We use protein kinase to transfer a single phosphoryl from this ATP onto the enzyme to produce this complex here. And this can either activate or usually inactivate the activity of that enzyme. And we also produce that ADP molecule.