Beta-lactamase OXA-1 (OXA-1)

OXA-1 beta-lactamase is a molecular class D serine enzyme that plays a significant role in bacterial resistance to beta-lactam antibiotics. Primarily found in Gram-negative pathogens such as Escherichia coli and Klebsiella pneumoniae, it is characterized by its ability to hydrolyze penicillins, particularly oxacillin and cloxacillin, and its relative resistance to traditional inhibitors like clavulanic acid and tazobactam (1.4.2, 1.5.3). The enzyme utilizes a unique catalytic mechanism involving a carboxylated lysine residue in its active site to facilitate the hydrolysis of the beta-lactam ring (1.4.3). OXA-1 is frequently encoded on mobile genetic elements such as plasmids and class 1 integrons, which allows for its rapid spread across different bacterial species (1.4.4, 1.5.1). Clinically, its presence is often associated with the co-carriage of other resistance determinants, including extended-spectrum beta-lactamases (ESBLs) like CTX-M-15, leading to multi-drug resistant phenotypes that complicate the treatment of serious infections such as bacteremia and pneumonia (1.1.1, 1.3.4). While traditional inhibitors are often ineffective, newer agents like avibactam and experimental penem inhibitors show potential in neutralizing its activity (1.3.2, 1.3.3).

Other names

Class D beta-lactamaseOxacillinase-1OXA-30PenicillinaseOxacillin-hydrolyzing beta-lactamase 1

Inhibition of the enzyme's catalytic activity to prevent the hydrolysis of beta-lactam antibiotics, thereby restoring their antibacterial efficacy.