Sulfanilamide is an antimicrobial drug that mimics the shape of an important substrate for a particular bacterial enzyme, thereby inhibiting the enzyme. This type of inhibition is known as Sulfanilamide is an antimicrobial drug that mimics the shape of an important substrate for a particular bacterial enzyme, thereby inhibiting the enzyme. This type of inhibition is known as feedback inhibition. competitive inhibition. allosteric activation. allosteric inhibition. noncompetitive inhibition.