The antibacterial activity of penicillin is related to the inhibition of a key bacterial enzyme. Explain this mechanism of enzyme inhibition.

Penicillin binds and inhibits bacterial enzyme DD-transpeptidase.

Explanation:

Penicillin is made up of 4 rings of β-lactam and acts by binding to DD-transpeptidase of bacteria. The DD-transpeptidase facilitates the cross-linking of the peptidoglycan cell wall of bacteria. This leads to malformation of the protective cell wall of the bacteria and causes it to lyze and die.