Editing Adenosine triphosphate (section)

=====Regulation=====
In glycolysis, [[hexokinase]] is directly inhibited by its product, glucose-6-phosphate, and [[pyruvate kinase]] is inhibited by ATP itself. The main control point for the glycolytic pathway is [[phosphofructokinase]] (PFK), which is allosterically inhibited by high concentrations of ATP and activated by high concentrations of AMP. The inhibition of PFK by ATP is unusual since ATP is also a substrate in the reaction catalyzed by PFK; the active form of the enzyme is a [[tetramer protein|tetramer]] that exists in two conformations, only one of which binds the second substrate fructose-6-phosphate (F6P). The protein has two [[binding site]]s for ATP&nbsp;– the [[active site]] is accessible in either protein conformation, but ATP binding to the inhibitor site stabilizes the conformation that binds F6P poorly.<ref name="Voet" /> A number of other small molecules can compensate for the ATP-induced shift in equilibrium conformation and reactivate PFK, including [[cyclic AMP]], [[ammonium]] ions, inorganic phosphate, and fructose-1,6- and -2,6-biphosphate.<ref name="Voet" /> {{confusing|date=October 2024}}