But the protein phosphatases use a completely different reaction mechanism, a completely different reaction pathway to actually reverse the effect of the protein kinase and remove this phosphoryl group. And that can basically either activate or deactivate the activity of that enzyme. So if phosphorylation activates that enzyme, then defosphorylation will deactivate the activity of that enzyme. And protein kinase is basically phosphorylate while protein phosphatases defosphorylate. And they use the following hydrolysis reaction. So basically this is that modified residue of that enzyme.