Final answer:
The inhibitor that binds to the enzyme but not to the enzyme-substrate complex is a noncompetitive inhibitor, which affects the enzyme's functionality by altering its conformation through allosteric site binding.
Step-by-step explanation:
The type of inhibitor that binds to the enzyme (E) but not to the enzyme-substrate (ES) complex is a noncompetitive inhibitor. Noncompetitive inhibition occurs when an inhibitor binds to an enzyme at an allosteric site, which is a location distinct from the active site. This binding alters the enzyme's conformation, affecting its active site and thus its functionality, without directly competing with the substrate for the active site. The presence of more substrate does not overcome the inhibitor's effect, differentiating it from competitive inhibition.