Table 2. Antimicrobial susceptibility profile produced by the β-lactamase OXA-143.

	MIC (µg ml−1)
	E. coli JM83			A. baumannii ATCC 17978
Antimicrobial	Control†	OXA-143	Fold change	Control†	OXA-143	Fold change
Ampicillin	2	1024	512	64	4096	64
Amoxicillin	4	2048	512	32	>2048	>64
Oxacillin	256	1024	4	512	2048	4
Ticarcillin	2	2048	1024	8	4096	512
Piperacillin	2	128	64	16	1024	64
Cephalothin	4	8	2	256	512	2
Cefoxitin	2	2	—	32	64	2
Ceftazidime	0.25	0.25	—	2	2	—
Cefotaxime	0.031	0.031	—	8	8	—
Aztreonam	0.062	0.062	—	32	32	—
Imipenem	0.125	1	8	0.125	128	1024
Meropenem	0.031	1	32	0.25	256	1024
Ertapenem	0.004	4	1024	2	1024	512
Doripenem	0.031	1	32	0.125	256	2048

^†Parental E. coli JM83 and A. baumannii ATCC 17978 strains without a β-­lactamase gene.