BlaPSZ-1, a novel AmpC gene identified from a Pantoea isolate

Background Pantoea species of the family Erwiniaceae are well-known plant pathogens and animal human conditional pathogens. Due to widespread continuous use antimicrobials, multidrug-resistant strains continue emerge, making clinical treatment difficult; therefore, there is an increasing need clarify mechanisms drug resistance. Methods A rabbit anal fecal sample was collected by a swab streak plate method used isolate single colonies. The standard agar dilution determine minimum inhibitory concentrations (MICs) against antimicrobials. complete genome sequence bacterium obtained using Next-Generation Sequencing platforms. potential resistance gene annotated based on Comprehensive Antibiotic Resistance Database (CARD) verified molecular cloning. β-lactamase PSZ-1 expressed via pCold I expression vector its enzyme kinetic parameters were analyzed. genetic environment evolutionary process novel gene-related sequences analyzed bioinformatic methods. Results endophytica X85 showed some degree penicillins as well cephalosporins. AmpC gene, designated bla in this research, identified be encoded plasmid (pPEX85) P. X85. Bla several first-, second-and third-generation cephalosporins aztreonam, but it did not show fourth-generation or carbapenems tested. Enzyme assays revealed that could hydrolyze amoxicillin, penicillin G, cephalothin, cefazolin, hydrolytic activity strongly inhibited inhibitor avibactam, which generally consistent with antimicrobial susceptibility testing results. No observed for aztreonam. Conclusion In study, PSZ-1, characterized It shows discovery can help guide scientific drugs husbandry practice, effectively avoiding abuse antimicrobials thus preventing further development spread bacterial