TABLE 1.

MICs of β-lactams for B. bronchiseptica DOR, B. parapertussis CIP 63.33, E. coli DH10B harboring recombinant plasmid pFL-1 expressing BOR-1 from B. bronchiseptica DOR, and the E. coli DH10B reference strain

β-Lactam(s)b	MIC (μg/ml) for:
	B. bronchiseptica DOR	B. parapertussis CIP 63.33a	E. coli DH10B (pFL-1)a	E. coli DH10B
Amoxicillin	8	2	512	2
Amoxicillin + CLA	2	0.12	8	2
Ticarcillin	8	2	512	1
Ticarcillin + CLA	2	<0.06	64	1
Piperacillin	0.25	<0.06	8	1
Piperacillin + TZB	0.06	<0.06	4	1
Cephalothin	8	8	4	2
Imipenem	0.25	0.25	0.25	0.25
Cefoxitin	512	64	2	2
Cefuroxime	512	2	4	2
Cefotaxime	512	0.5	<0.06	<0.06
Ceftazidime	16	<0.06	<0.06	<0.06
Cefepime	16	<0.06	<0.06	<0.06
Cefpirome	512	<0.06	<0.06	<0.06
Aztreonam	512	0.06	0.06	0.06
Moxalactam	1	0.12	0.12	0.12

^aB. parapertussis CIP 63.33 and E. coli DH10B (pFL-1) produced β-lactamase BOR-1.

^bCLA, clavulanic acid at a fixed concentration of 2 μg/ml; TZB, tazobactam at a fixed concentration of 4 μg/ml.