. 2019 Oct 31;8(4):212. doi: 10.3390/pathogens8040212

Table 1.

Characterization of mcr-1, bla_NDM-9, and bla_CTX-M-55-positive E. coli YMC/2017/02/MS631 and its transconjugants.

Parameters	E. coli YMC/2017/ 02/MS631	Transconjugants
		Selected by Colistin	Selected by Imipenem	E. coli J53
		E. coli EJ533	E. coli EJ5331	E. coli J53
Source	Asymptomatic carrier	-	-	-
Isolation site	Rectal swab	-	-	-
Resistance genes	bla_NDM-9, bla_CTX-M-55, bla_TEM-1B, aph(3’)IIa, aph(3’)Ib, rmtB, aph(6)-Id, aadA2, oqxA, oqxB, fosA3, mph(A), mdf(A),floR, sul2, tet(A), dfrA12, mcr-1	mcr-1	bla_NDM-9, aadA2, fosA3, mph(A), dfrA12	-
MLST	617	-	-	-
Serotype	O89/162:H10	-	-	-
Plasmid replicon type(s)	IncB, IncFII, IncI2, IncN, IncY, IncR, IncX1	IncI2	IncB	-
Virulence factors	gad, iss
ompC, ompF	Intact
MIC (μg/mL, interpretation)
Amoxicillin-clavulanic acid	128, R ^†	4, S ^‡	8, R ^‡	4, S ^‡
Piperacillin	≥256, R ^†	N/D	N/D	N/D
Piperacillin-tazobactam	≥256, R ^†	≤4, S ^‡	≥128, R^‡	≤4, S ^‡
Cefotaxime	≥256, R ^†	≤1, S ^‡	≥64, R ^‡	≤1, S ^‡
Ceftazidime	≥256, R ^†	≤1, S ^‡	≥64, R ^‡	≤1, S ^‡
Cefepime	≥256, R ^†	≤1, S ^‡	≥64, R ^‡	≤1, S ^‡
Cefoxitin	≥256, R ^†	8, S ^‡	32, R ^§	≤1, S ^‡
Aztreonam	≥128, R ^†	≤1, S ^‡	≤1, S ^‡	≤1, S ^‡
Ertapenem	64, R ^†	≤0.5, S ^‡	4, R ^‡	≤0.5, S ^‡
Meropenem	16, R ^†	N/D	N/D	N/D
Imipenem	32, R ^†	≤0.25, S ^‡	8, R ^‡	≤0.25, S ^‡
Ceftazidime-avibactam	≥256, R ^†	N/D	N/D	N/D
Colistin	4, R ^‡	4, R ^‡	≤0.125, S ^‡	<0.125, S ^‡
Amikacin	≥16, R ^‡	≤2, S ^‡	≤2, S ^‡	≤2, S ^‡
Gentamicin	≥16, R ^‡	≤1, S ^‡	≤1, S ^‡	≤1, S ^‡
Ciprofloxacin	≥4, R ^‡	≤0.25, S ^‡	≤0.25, S ^‡	≤0.25, S ^‡
Tigecycline	0.5, S ^‡	≤0.5, S ^‡	≤0.5, S ^‡	≤0.5, S ^‡
Trimethoprim-sulfamethoxazole	320, R ^‡	≤20, S ^‡	≤20, S ^‡	≤20, S ^‡

Abbreviations: MIC, minimal inhibitory concentration; MLST, Multi Locus Sequence Type; N/D, not determined. In vitro antimicrobial susceptibility testing was performed using an agar dilution method † and a broth microdilution method ^‡ following the Clinical and Laboratory Standards Institute (CLSI) guidelines M100 28th ed. MIC interpretations followed CLSI M100 28th ed, with the exception of tigecycline and colistin, for which the European Committee on Antimicrobial Susceptibility Testing guidelines v9.0 were applied.