IMP-26 was a rare IMP variant with more carbapenem-hydrolyzing activities, which was increasingly reported now in China. This study characterized a transferable multidrug resistance plasmid harboring
bla
IMP-26
from one
Enterobacter cloacae
bloodstream isolate in Shanghai and investigated the genetic environment of resistance genes. The isolate was subjected to antimicrobial susceptibility testing and multilocus sequence typing using broth microdilution method, Etest and PCR. The plasmid was analyzed through conjugation experiments, S1-nuclease pulsed-field gel electrophoresis and hybridization. Whole genome sequencing and sequence analysis was conducted for further investigation of the plasmid.
E. cloacae
RJ702, belonging to ST528 and carrying
bla
IMP-26
,
bla
DHA-1
,
qnrB
4 and
fosA5
, was resistant to almost all β-lactams, but susceptible to quinolones and tigecycline. The transconjugant inherited the multidrug resistance. The resistance genes were located on a 329,420-bp IncHI2 conjugative plasmid pIMP26 (ST1 subtype), which contained
trhK/trhV
,
tra
,
parA
and
stbA
family operon. The
bla
IMP-26
was arranged following
intI1
. The
bla
DHA-1
and
qnrB4
cluster was the downstream of IS
CR1
, same as that in p505108-MDR. The
fosA5
cassette was mediated by IS
4
. This was the first report on complete nucleotide of a
bla
IMP-26
-carrying plasmid in
E. cloacae
in China. Plasmid pIMP26 hosted high phylogenetic mosaicism, transferability and plasticity.