Source:http://linkedlifedata.com/resource/umls/id/C0037540
NCI: The sodium salt form of benzylpenicillin, a semi-synthetic, broad-spectrum penicillin antibiotic with bactericidal activity. Benzylpenicillin sodium binds to and inactivates penicillin-binding proteins (PBP) located on the inner membrane of the bacterial cell wall. Inactivation of PBPs interferes with the cross-linkage of peptidoglycan chains necessary for bacterial cell wall strength and rigidity. This results in the weakening of the bacterial cell wall and causes cell lysis.