How does penicillin work?

How does penicillin work?

• A. Inhibits cell wall synthesis
• B. Inhibits protein synthesis
• C. Increases membrane permeability
• D. Inactivates enzymes

Answer: (A)

Penicillin works by targeting the bacterial cell wall. It binds to penicillin-binding proteins and blocks the enzymes (transpeptidases) that cross-link peptidoglycan strands. Without this cross-linking, the cell wall becomes weak as bacteria grow, and the cell bursts under osmotic pressure, making penicillin bactericidal. This mechanism is distinct from inhibiting protein synthesis, increasing membrane permeability, or inactivating enzymes in general, which are actions of other drug classes.

Penicillin works by targeting the bacterial cell wall. It binds to penicillin-binding proteins and blocks the enzymes (transpeptidases) that cross-link peptidoglycan strands. Without this cross-linking, the cell wall becomes weak as bacteria grow, and the cell bursts under osmotic pressure, making penicillin bactericidal. This mechanism is distinct from inhibiting protein synthesis, increasing membrane permeability, or inactivating enzymes in general, which are actions of other drug classes.