confers_resistance_to_antibiotic confers_resistance_to_antibiotic ampicillin cefalotin OXA-50 OXA-50 is a beta-lactamase found in Pseudomonas aeruginosa. It confers decreased susceptibility to ampicillin and ticarcillin and, interestingly, to moxalactam and meropenem in P. aeruginosa but not in E. coli. Also confers resistance to piperacillin-tazobactam and cephalotin. antibiotic_resistance OXA-50 ARO:3001796 OXA-50-like beta-lactamase