- Penicillin exerts its antibacterial effect by inhibiting the enzyme transpeptidase, which is crucial for cross-linking peptidoglycan chains in bacterial cell walls.
- This leads to weakened cell walls and bacterial lysis, particularly in actively dividing bacteria.
- Since peptidoglycan is unique to bacteria, penicillin selectively targets bacterial cells without affecting human cells.
- This mechanism disrupts peptidoglycan synthesis, making it bactericidal.