TABLE 1.
Distribution of mcr-1-positive Enterobacteriaceae isolated from aquatic environments and the MICs of commonly used antibiotics for original isolates and their mcr-1-positive transconjugants
Aquatic environment | Isolate no. | Organism | MIC (μg/ml)a |
Other resistance genes | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
IPM | GEN | CTX | TZP | SCF | AMK | TIM | CSTd | FEP | CAZ | CRO | CIP | ||||
East River | ER-1 | E. coli | 0.19 | 2 | 0.047 | 0.75 | 0.38 | 4 | 3 | 2 | 0.023 | 0.094 | 0.047 | 0.25 | qnrS |
ER-2 | E. coli | 0.125 | 0.75 | >256b | 1 | 2 | 2 | 4 | 2 | 6 | 4 | 64b | 0.012 | blaCTX-M-15 | |
ER-1-Tc | 0.19 | 0.75 | 0.094 | 2 | 0.25 | 2 | 4 | 1 | 0.047 | 0.38 | 0.094 | 0.125 | |||
ER-2-T | 0.19 | 0.75 | 32b | 3 | 1 | 2 | 6 | 1 | 1.5 | 4 | 48b | 0.125 | |||
Huajiachi Lake | HJCL-1 | E. coli | 0.19 | 0.75 | 0.047 | 1.5 | 0.5 | 3 | 4 | 4b | 0.047 | 0.19 | 0.047 | 0.006 | |
HJCL-2 | E. coli | 0.125 | 1 | 0.047 | 2 | 0.38 | 3 | 2 | 4b | 0.064 | 0.094 | 0.032 | 0.75 | qnrS | |
HJCL-3 | E. coli | 0.25 | >256b | 0.094 | 4 | 2 | >256b | 24 | 4b | 0.38 | 0.125 | 0.064 | >32b | oqxA, oqxB | |
HJCL-4 | E. coli | 0.19 | 48b | 0.5 | 12 | 1.5 | >256b | 24 | 2 | 1.5 | 0.094 | 0.064 | >32b | oqxB | |
HJCL-5 | C. freundii | 0.25 | 16b | 0.25 | 3 | 1 | 24 | 3 | 2 | 0.032 | 0.75 | 0.38 | 1 | qnrB | |
HJCL-6 | C. braakii | 0.5 | 24b | 0.38 | 3 | 1 | 32 | 2 | 2 | 0.064 | 0.75 | 0.5 | 0.5 | qnrB | |
HJCL-7 | K. oxytoca | 0.25 | 2 | 0.025 | 1.5 | 1 | 32 | 1.5 | 32b | 0.023 | 0.064 | 0.047 | 0.75 | qnrS, oqxB | |
HJCL-8 | K. oxytoca | 0.75 | 1.5 | 0.025 | 1 | 1 | 24 | 1.5 | 32b | 0.016 | 0.047 | 0.032 | 0.75 | qnrS, oqxB | |
HJCL-9 | C. braakii | 0.38 | 8 | 0.025 | 6 | 4 | 16 | 32 | 4b | 0.125 | 0.19 | 0.38 | >32b | blaTEM-1, qnrB, oqxA, oqxB | |
HJCL-10 | C. freundii | 0.25 | 8 | 0.125 | 4 | 1 | 8 | 8 | 4b | 0.125 | 0.25 | 0.19 | >32b | blaTEM-1, qnrB, oqxA, oqxB | |
HJCL-1-T | 0.25 | 0.75 | 0.064 | 3 | 0.19 | 2 | 4 | 1 | 0.047 | 0.38 | 0.094 | 0.125 | |||
HJCL-3-T | 0.25 | 0.75 | 0.094 | 2 | 0.25 | 2 | 4 | 4b | 0.064 | 0.38 | 0.094 | 0.125 | |||
HJCL-4-T | 0.19 | 0.75 | 0.094 | 3 | 0.25 | 3 | 6 | 1 | 0.064 | 0.38 | 0.094 | 0.125 | |||
HJCL-5-T | 0.19 | 0.75 | 0.094 | 2 | 0.25 | 2 | 4 | 1 | 0.064 | 0.38 | 0.064 | 0.125 | |||
HJCL-6-T | 0.19 | 0.75 | 48b | 3 | 1 | 2 | 8 | 2 | 2 | 4 | 48b | 0.125 | |||
Tiesha River | TSR-1 | E. coli | 0.094 | 0.19 | 0.094 | 4 | 1 | 3 | 6 | 1 | 0.064 | 0.19 | 0.064 | 0.047 | blaTEM-1, oqxB |
TSR-2 | E. coli | 0.125 | 0.75 | 0.125 | 3 | 0.75 | 2 | 8 | 1 | 0.064 | 0.125 | 0.064 | 0.047 | blaTEM-1, oqxB | |
TSR-1-T | 0.25 | 0.75 | 0.094 | 2 | 0.25 | 2 | 3 | 1 | 0.047 | 0.25 | 0.064 | 0.125 | |||
TSR-2-T | 0.19 | 0.75 | 0.094 | 3 | 0.25 | 2 | 3 | 1 | 0.047 | 0.38 | 0.094 | 0.125 | |||
Nine Creeks | NC-1 | E. coli | 0.125 | 1.5 | 0.094 | 2 | 2 | 6 | 12 | 2 | 0.094 | 0.19 | 0.064 | 0.5 | qnrS |
Qiantang River | QTR-1 | E. coli | 0.19 | 1.5 | 0.19 | 4 | 0.5 | 4 | 4 | 4b | 0.125 | 0.5 | 0.094 | >32b | |
QTR-2 | E. coli | 0.25 | 1.5 | 2 | >256b | 6 | 3 | 16 | 4b | 48b | 24b | >256 | 0.012 | qnrS | |
QTR-2-T | 0.094 | 1.5 | 0.047 | 1.5 | 0.38 | 4 | 2 | 8b | 0.047 | 0.094 | 0.032 | 0.19 | |||
Xixi Wetland | XXWL-1 | E. coli | 0.125 | 32b | 48b | 0.38 | 4 | 3 | 8 | 4b | 6 | 8 | 96b | >32b | blaCTX-M-55, blaTEM-1, oqxB |
XXWL-2 | E. coli | 0.19 | 48b | 128b | 1 | 4 | 3 | 16 | 2 | 6 | 8 | >256b | >32b | blaCTX-M-15 | |
XXWL-3 | E. coli | 0.25 | 32b | 128b | 1 | 4 | 6 | 6 | 2 | 6 | 8 | >256b | >32b | blaCTX-M-15, blaTEM-1, oqxB | |
XXWL-4 | E. coli | 0.19 | 1.5 | 0.047 | 1.5 | 0.25 | 3 | 4 | 2 | 0.032 | 0.094 | 0.047 | 0.25 | qnrS | |
XXWL-1-T | 0.19 | 0.75 | 0.094 | 3 | 0.25 | 2 | 4 | 1 | 0.047 | 0.38 | 0.094 | 0.19 | |||
XXWL-2-T | 0.25 | 1 | 0.094 | 3 | 0.25 | 2 | 3 | 1 | 0.047 | 0.38 | 0.094 | 0.19 | |||
XXWL-3-T | 0.19 | 0.75 | 0.094 | 2 | 0.25 | 2 | 4 | 1 | 0.064 | 0.38 | 0.094 | 0.19 | |||
Jinghang Grand Canal | JHGC-1 | E. coli | 0.19 | 1.5 | 0.094 | 2 | 0.75 | 3 | 12 | 2 | 0.064 | 0.19 | 0.064 | 0.5 | |
JHGC-2 | E. cloacae | 0.25 | 1.5 | 0.125 | 2 | 0.5 | 4 | 1.5 | 2 | 0.047 | 0.125 | 0.38 | 0.19 | qnrS | |
JHGC-1-T | 0.19 | 0.75 | 0.094 | 3 | 0.125 | 2 | 4 | 1 | 0.064 | 0.25 | 0.064 | 0.125 |
IPM, imipenem; GEN, gentamicin; CTX, cefotaxime; TZP, piperacillin-tazobactam; SCF, cefoperazone/sulbactam; AMK, amikacin; TIM, ticarcillin-clavulanic acid; CST, colistin; FEP, cefepime; CAZ, ceftazidime; CRO, ceftriaxone; CIP, ciprofloxacin.
Resistance.
T, transconjugant.
MIC of colistin (CST) was determined using the broth microdilution method.