penicillin is an antibiotic that kills bacteria by binding to the active site of an enzyme involved in synthesis of the bacterial cell wall. which of the following phenomena best describes the mechanism of action of penicillin? penicillin is an antibiotic that kills bacteria by binding to the active site of an enzyme involved in synthesis of the bacterial cell wall. which of the following phenomena best describes the mechanism of action of penicillin? noncompetitive inhibition competitive inhibition allosteric regulation feedback inhibition