Table 2.

MICs of carbapenems and cephalosporins for Citrobacter isolates F1 and N6, transconjugants E. coli J53::KPC, and recipient strain E. coli J53.

	MIC, mg/L (Susceptibility)
	ETP	MEM	IPM	CAZ	CTX
E. Coli J53	0.012 (S)	0.016 (S)	0.38 (S)	0.047 (S)	0.016 (S)
Citrobacter F1	>32 (R)	16 (R)	>32 (R)	>256 (R)	12 (R)
E. coli J53 (F1.1t)	0.125 (S)	0.5 (S)	2 (S)	12 (R)	3 (R)
Citrobacter N6	2 (R)	8 (IR)	>32 (R)	64 (R)	6 (R)
E. coli J53 (N6.1t)	0.75 (R)	0.5 (S)	8 (R)	32 (R)	4 (R)

ETP, ertapenem; MEM, meropenem; IPM, imipenem; CAZ, ceftazidime; CTX, cefotaxime (R, resistant; IR, intermediate; S, susceptible).