CephalosporinaseCitrobacterbeta-LactamasesPenicillinaseCloxacillinCephalosporinsEnterobacterbeta-LactamsHafnia alveiProteus vulgarisEnterobacter cloacaeCephaloridinePenicillanic AcidCeftazidimeCefoxitinCitrobacter freundiiAnti-Bacterial AgentsMicrobial Sensitivity TestsAztreonamSulbactambeta-Lactam ResistanceCephalosporin ResistanceIsoelectric FocusingDrug Resistance, MicrobialEnterobacter aerogenesProteusHydrolysisClavulanic AcidMoxalactamImipenemEscherichia coliSerratia marcescensCefotaximePseudomonas aeruginosaClavulanic AcidsEnterobacteriaceaeThienamycinsAcinetobacter baumanniiEnzyme InductionGenes, BacterialAcinetobacterPlasmidsPenicillin GCarbapenemsEnterobacteriaceae InfectionsGram-Negative BacteriaKineticsMolecular Sequence DataKlebsiella pneumoniaeChromosomes, BacterialBacterial ProteinsAmidohydrolasesCloning, MolecularPenicillinsDNA, Bacterial