Which of the following actions does Benzylpenicillin perform?

Benzylpenicillin, also known as penicillin G, primarily works by inhibiting cell wall synthesis in bacteria. This action is critical because bacterial cell walls are essential for maintaining the structural integrity of the bacteria. The drug binds to specific proteins known as penicillin-binding proteins (PBPs), which play a vital role in the cross-linking of peptidoglycan layers that form the cell wall. By disrupting this cross-linking process, Benzylpenicillin weakens the cell wall, ultimately leading to cell lysis and death, especially in actively dividing bacteria.

The other choices highlight different mechanisms that do not apply to Benzylpenicillin. For example, inhibiting RNA or nucleic acid synthesis relates to antibiotics like fluoroquinolones, while enhancing cell wall permeability does not directly describe the action of Benzylpenicillin. Therefore, understanding the specific mechanism of action of Benzylpenicillin is crucial for recognizing its role in treating bacterial infections effectively.