Question

The nurse is serving as a preceptor for a graduate nurse on a medical-surgical unit. The nurse, who is discussing the mechanisms of action of antibiotics, currently is talking about the mechanism of action of penicillins. Which statement by the graduate nurse best demonstrates understanding? "Penicillin works by

Answer 1

The graduate nurse demonstrates understanding by stating that penicillin works by irreversibly inhibiting the transpeptidase enzyme, preventing bacterial cell wall synthesis.

Step-by-step explanation:

The graduate nurse best demonstrates an understanding of the mechanism of action of penicillins by stating: "Penicillin works by irreversibly inhibiting the enzyme transpeptidase, preventing the synthesis of the bacterial cell wall." This results in the lack of production of new peptide crosslinks in the peptidoglycan layer, essential for the bacteria's integrity, leading to cell wall degradation and eventually the bursting of the bacterial cell (cytolysis). As penicillins belong to the class of β-lactam antibiotics, their active site, the β-lactam ring, mimics the structure of the peptidoglycan component in the bacterial cell wall targeted by transpeptidase, thus allowing it to bind to and inactivate the enzyme. Additionally, penicillin is particularly effective against gram-positive bacteria, and certain gram-negative bacteria, including E. coli. It is used in the treatment of various infections, such as diphtheria and pneumonia.