TABLE 1.

Comparison of β-lactam MICs for strain CF01Ent1 and E. coli DH5α transformants containing AmpR-AmpC-encoding plasmid pCF01Ent1-8 or AmpC-encoding plasmid pCF01Ent1-3

Substrate	MIC (μg/ml)
	CF01Ent1	E. coli DH5α (pCF01BA1-8)	E. coli DH5α (pCF01BA1-3)	E. coli DH5α
Amoxicillin	32	256	1,024	2
Amoxicillin + CLAa	32	256	1,024	2
Ticarcillin	1	64	256	2
Ticarcillin + CLA	0.5	64	256	2
Piperacillin	2	8	32	2
Piperacillin + TZB	2	8	32	2
Cephalothin	64	256	512	4
Cefuroxime	8	64	64	4
Cefoxitin	32	128	128	4
Cefotaxime	0.25	2	8	0.06
Cefpirome	0.06	0.06	1	0.06
Cefepime	0.06	0.06	1	0.06
Ceftazidime	0.25	8	32	0.12
Aztreonam	0.12	2	2	0.12
Imipenem	0.5	0.25	0.25	0.12

^aCla, clavulanate at a fixed concentration of 2 μg/ml; TZB, tazobactam at a fixed concentration of 4 μg/ml.