In the section about the induced fit model for enzyme substrate binding, my MCAT textbook claims that "The substrate has induced a change in the shape of the enzyme. This interaction requires energy, and therefore, this part of the reaction is endergonic."
As a chemist, I am a bit confused here because induced fit suggests that some kind of bonding must be happening between the enzyme and substrate (hydrogen, ionic, covalent, etc) that would induce a change in structure of both enzyme and substrate. Any kind of bond formation is STRICTLY enthalpically exothermic, so why is the formation of an enzyme-substrate complex endergonic?
Am I missing an entropic component here? Or is my assumption wrong, regarding how the induced fit chemistry operates?
I would assume that it would TAKE energy to then cleave/break all the bonds that induced structural change and release the catalyzed substrate...