Carbapenem-Resistant Enterobacter hormaechei ST1103 with IMP-26 Carbapenemase and ESBL Gene bla_SHV-178

Figures & data

Table 1 Antimicrobial Susceptibility Profile of Enterobacter hormaechei L51

Drug Class	Antimicrobial Drug	MIC (mg/L)	R/I/S
Penicillins	Amoxicillin-clavulanate	128/64	R
	Piperacillin-tazobactam^a	16/4	S
Cephalosporins	Cefotaxime	≥128	R
	Ceftazidime	≥128	R
	Cefepime	16	R
	Cefpirome	32	R
Carbapenems	Meropenem	8	R
	Imipenem	8	R
	Ertapenem	8	R
Monobactams	Aztreonam	128	R
Aminoglycosides	Gentamicin	128	R
	Amikacin	2	S
	Tobramycin	16	R
Fluoroquinolones	Ciprofloxacin	1	R
	Levofloxacin	0.5	I
Tetracyclines	Tetracycline	≥128	R
	Tigecycline	1	S
Others	Trimethoprim-sulfamethoxazole	≥8	S
	Chloramphenicol	≥128	R
	Nitrofurantoin	32	R
	Fosfomycin	128	I
	Colistin	0.5	S

Note: ^aTazobactam at a fixed concentration of 4mg/L.

Abbreviations: R, resistant; I, intermediary; S, susceptible.

Table 2 Antibiotic Resistance Genes in Plasmid of Enterobacter hormaechei L51

Drug Class	Coding Genes	Gene Family, Description	Position
Aminoglycoside	aac(3)-IIc	AAC(3)	297,252–298,061
	aac(6ʹ)-IIc	AAC(6ʹ)	300,146–300,727
Beta-lactamase	blaSHV-178	SHV beta-lactamase	270,538–271,398
	blaDHA-1	DHA beta-lactamase	278,802–279,941
	blaTEM-1	TEM beta-lactamase	117,616–118,476
	blaIMP-26	IMP beta-lactamase	130,800–131,540
Macrolide	ereA2	Macrolide esterase	299,713–299,940
Streptogramin	mrx	Macrolide phosphotransferase (MPH)	90,384–91,622
	mph(A)		91,619–92,524
Phenicol	catII	Chloramphenicol acetyltransferase (CAT)	261,382–262,023
Fosfomycin	fosA5	Fosfomycin thiol transferase	142,659–143,078
Fluoroquinolone	qnrB4	Quinolone resistance protein (qnr)	284,062–284,709
Tetracycline	tet(D)	Major facilitator superfamily (MFS) antibiotic efflux pump	258,586–259,770
Sulphonamide	sul1	Sulfonamide resistant sul	293,427–294,266
Trimethoprim	dfrA19	Trimethoprim resistant dihydrofolate reductase dfr	128,462–129,031

Figure 1 The phylogenetic tree of 61 completed E. hormaechei genome generated by the Harvest suite, where Enterobacter hormaechei SCEH020042 is used as the standard strain. Enterobacter hormaechei subsp. hoffmannii strains and E. hormaechei subsp. xiangfangensis strains are marked in pink and blue, respectively.

Figure 2 The identification of plasmid size using S1-PFGE (left) and southern blot and hybridization (right). The pEHZJ1 plasmid was between 336.5kbp and 398.4kbp, and was positive for a probe against bla_IMP-26.

Figure 3 The genetic features of the pEHZJ1 plasmid.

Notes: (A) Comparison of the pEHZJ1 plasmid sequence with pIMP26 using BRIG. The MDR-1 region, MDR-2 region and tra-par-trh-rep region are indicated in orange, pink and dark blue, respectively. Insert sequence and transposons are indicated in green. (B) Genetic features of MDR regions (MDR-1 and MDR-2) and a comparison of genes surrounding bla_IMP-26 on pEHZJ1, pIMP26 (GenBank: MH399264.1) and pEI1573 (GenBank: JX101693.1). Gray regions denote regions that are homologous with >95% nucleotide similarity. bla_IMP-26 is indicated in red and class 1 integrons are marked by straight lines.