On the enzyme hexokinase, ATP reacts with glucose to produce glucose 6-phosphate and ADP five orders of magnitude faster than AT
P reacts with H2O to form phosphate and ADP. The intrinsic chemical reactivity of the —OH group in water is about the same as that of the glucose molecule, and water can certainly fit into the active site. Explain this rate differential in two sentences or less.
[The rate differential results from induced fit on the enzyme upon binding of glucose. This conformational change excludes water from gaining access to the -phosphate group on ATP, and brings the same group close to the OH group on carbon 6 of glucose]