Apalcillin

**Semantic type:** Antibiotic|Pharmacologic Substance

**Definition:** A naphthydridine derivative of the broad spectrum, semisynthetic ampicillin with antibacterial activity. Apalcillin specifically binds to and inactivates penicillin-binding proteins (PBPs) located on the inner membrane of the bacterial cell wall, thereby preventing the cross-linkage of peptidoglycans, which are critical components of the bacterial cell wall. This leads to a weakening of the bacterial cell wall, eventually causing bacterial cell lysis.

**Synonyms:** - APALCILLIN