B .55 uncat ES EP Reaction coordinate figure 8-6 Role of binding energy in catalysis. To lower the activa tion energy for a reaction, the system must acquire an amount of energy equivalent to the amount by which AG iS lowered. Much of this energy comes from binding energy(AGB) contributed by formation of weak noncova lent interactions between substrate and enzyme in the transition state. The role of A GB is analogous to that of △ GM in Figure8-5