TABLE 2.

Antimicrobial susceptibility and molecular typing of resistance mechanisms of clinical isolates and transconjugant strains

Antimicrobial agent or genetic determinanta	MIC (μg/ml) or molecular typing resultb
	Donor clinical isolatesc							E. coli transconjugant strainsd							E. coli transf.e	E. coli acceptors
	Ecl Q4010	Ecl Q3039	Ecl Q2054	Ecl Q5161	Cfr Q1174	Cfr Q4143	Eae Q4079	ER-4010	ER-3039	J-2054	J-5161	J-1174	J-4143	J-4079		ER1793	J53
Antimicrobial susceptibility testing
AMK	≥256	≥256	≥256	≥256	≥256	≥256	≥256	≥256	≥256	≥256	≥256	≥256	≥256	≥256	≥256	0.5	1.5
GEN	≥1,024	≥1,024	256	256	≥1,024	≥1,024	256	≥1,024	≥256	≥256	≥256	768	768	256	≥256	0.125	1.5
KAN	≥256	≥256	≥256	≥256	≥256	≥256	≥256	≥256	≥256	≥256	≥256	≥256	≥256	≥256	≥256	0.75	2
NET	≥256	≥256	≥256	≥256	≥256	≥256	≥256	≥256	≥256	≥256	≥256	≥256	≥256	≥256	≥256	0.125	0.125
TOB	≥1,024	≥1,024	≥1,024	≥1,024	≥1,024	768	256	≥1,024	≥256	256	≥256	≥1,024	256	256	≥256	0.094	1
APR	8	4	8	8	8	4	8	ND	ND	ND	ND	ND	ND	ND	ND	4	4
AMP	≥256	≥256	≥256	≥256	≥256	≥256	≥256	64	≥256	48	≥256	96	≥256	≥256	ND	6	6
PIP	≥256	≥256	≥256	≥256	≥256	≥256	≥256	8	16	6	≥256	4	≥256	≥256	ND	1	2
FOX	≥256	≥256	≥256	≥256	≥256	≥256	≥256	2	4	12	8	12	12	16	ND	8	8
CAZ	192	≥256	128	≥256	≥256	24	12	0.125	0.25	0.125	0.5	0.19	8	16	ND	0.125	0.19
CTX	≥256	≥256	≥256	≥256	≥256	≥256	≥256	0.047	0.064	0.094	0.38	0.094	192	≥256	ND	0.094	0.094
FEP	6	192	4	24	12	256	128	0.094	0.094	0.125	0.38	0.094	24	48	ND	0.047	0.064
IPM	0.75	1.5	2	2	0.75	0.38	0.75	0.25	0.25	0.25	0.25	0.75	0.25	0.25	ND	0.25	0.38
ERT	8	24	16	≥32	6	0.75	0.5	0.012	0.016	0.012	0.012	0.012	0.032	0.023	ND	0.016	0.008
MEM	1	0.5	1.5	3	3	0.25	0.094	0.023	0.023	0.023	0.023	0.032	0.047	0.023	ND	0.023	0.023
CIP	≥32	≥32	≥32	≥32	≥32	≥32	0.19	0.125	0.19	0.016	0.008	0.016	0.75	0.016	ND	0.125	0.012
TET	48	48	96	256	256	48	24	1.5	4	2	6	4	4	4	ND	0.5	1
CHL	256	96	128	256	≥256	24	≥256	12	24	16	16	48	48	≥256	ND	3	6
PCR
armA	−	−	−	−	−	−	−	ND	ND	ND	ND	ND	ND	ND	ND	ND	ND
rmtA	−	−	−	−	−	−	−	ND	ND	ND	ND	ND	ND	ND	ND	ND	ND
rmtB	−	−	−	−	−	−	−	ND	ND	ND	ND	ND	ND	ND	ND	ND	ND
rmtC	−	−	−	−	−	−	−	ND	ND	ND	ND	ND	ND	ND	ND	ND	ND
rmtD	+	+	+	+	+	+	+	+	+	+	+	+	+	+	ND	ND	ND
npmA	−	−	−	−	−	−	−	ND	ND	ND	ND	ND	ND	ND	ND	ND	ND
blaTEM	+	+	−	−	−	+	+	+	−	ND	ND	ND	−	+	ND	ND	ND
blaSHV	−	−	−	−	−	−	−	ND	ND	ND	ND	ND	ND	ND	ND	ND	ND
blaKPC	−	−	−	−	−	−	−	ND	ND	ND	ND	ND	ND	ND	ND	ND	ND
blaCTX-M	−	−	−	+	−	+	+	ND	ND	ND	+	ND	+	+	ND	ND	ND
qnrB	−	−	−	−	−	+	−	ND	ND	ND	ND	ND	+	ND	ND	ND	ND

^aAMK, amikacin; GEN, gentamicin; KAN, kanamycin; NET, netilmicin; TOB, tobramycin; APR, apramycin; AMP, ampicillin; PIP, piperacillin; FOX, cefoxitin; CAZ, ceftazidime; CTX, cefotaxime; FEP, cefepime; IPM, imipenem; ERT, ertapenem; MEM, meropenem; CIP, ciprofloxacin; TET, tetracycline; CHL, chloramphenicol.

^b+ and −, positive and negative amplification, respectively; ND, not determined.

^cEcl, E. cloacae; Cfr, C. freundii; Eae, E. aerogenes.

^dTransconjugant strains are designated with the letter from the acceptor E. coli strain (ER- and J- indicate derivation from E. coli ER1793 and J53, respectively) and the number from the donor clinical strain.

^eE. coli transformed with the rmtD2 gene.