Table 1. Bacterial strains and plasmids used in this study.

Strain or plasmid	Descriptiona	Source or reference
Strains
K. pneumoniae
ZAT242	Clinical isolate with plasmid pCT	This study
CGMHKL1	Clinical isolate with plasmid pSH	This study
VGC263	Clinical isolate with plasmid pDH	This study
KPC2010	Clinical isolate with plasmid pKP	[11]
TAI2010	Clinical isolate with plasmid pND	[27]
NVT2001S	Streptomycin-resistant isolate of clinical strain NVT2001	[9]
ΔompK35 mutant	ompK35 deletion strain of NVT2001S; Smr	[9]
ΔompK36 mutant	ompK36 deletion strain of NVT2001S; Smr	[9]
ΔompK35/36 mutant	ompK35 and ompK36 deletion strain of NVT2001S; Smr	[9]
E. coli
J53	A recipient for conjugation experiment; Azr	[28]
Plasmids
pACYC177	Low-copy-number plasmid; Apr Kmr	New England Biolabs
pCT	Plasmid from clinical isolate containing bla CTX-M-15	This study
pSH	Plasmid from clinical isolate containing bla SHV-12	This study
pDH	Plasmid from clinical isolate containing bla DHA-1-ampR	This study
pKP	Plasmid from clinical isolate containing bla KPC-2 and bla TEM-1	[11]
pND	Plasmid from clinical isolate containing bla NDM-1	[27]
pCT177	Fragment containing bla CTX-M-15 and its flanking region cloned into pACYC177	This study
pSH177	Fragment containing bla SHV-12 and its flanking region cloned into pACYC177	This study
pDH177	Fragment containing bla DHA-1-ampR and its flanking region cloned into pACYC177	This study
pDHA177	Fragment containing bla DHA-1 and its flanking region cloned into pACYC177	This study
pAmpR177	Fragment containing ampR and its flanking region cloned into pACYC177	This study
pKP177	Fragment containing bla KPC-2 and its flanking region cloned into pACYC177	This study
pND177	Fragment containing bla NDM-1 and its flanking region cloned into pACYC177	This study

^aAp^r, resistance to ampicillin; Az^r, resistance to azide; Km^r, resistance to kanamycin; Sm^r, resistance to streptomycin.