Table 1.
Antimicrobial-resistance profile of blaESBL- and blaCMY-2-producing E. coli clinical isolates and their transconjugants.
| E. coli Isolates | Conjugation Frequency a (CFU/Donor Cell) |
Resistance Genes | Resistance Profile |
|---|---|---|---|
| EC13655 | blaTEM, blaCTX, blaCMY-2 | CTX, CAZ, CPD, ATM, CIP, CRO, DO, FEP, CX, IPM, SXT | |
| Transconjugant of EC13655 | 1.02 × 10−6 | blaTEM, blaCTX | CTX, CAZ, CPD, ATM, CIP, CRO, DO, FEP, CX, IPM, SXT, RD |
| EC14149 | blaSHV, blaCMY-2 | CTX, CAZ, CPD, ATM, CIP, CN, CRO, FEP, CX, IPM, SXT | |
| Transconjugant of EC14149 | 2.27 × 10−5 | blaSHV, blaCMY-2 | CTX, CAZ, CPD, ATM, CIP, CRO, FEP, CX, IPM, RD |
| EC14437 | blaCTX, blaCMY-2 | AMC, CTX, CAZ, CPD, ATM, CIP, CN, CRO, DO, FEP, CX, SXT | |
| Transconjugant of EC14437 | 3.53 × 10−4 | blaCTX, blaCMY-2 | AMC, CTX, CAZ, CPD, CIP, CRO, FEP, SXT, RD |
| EC11994 | blaSHV, blaCMY-2 | AMC, CTX, CAZ, CPD, ATM, CRO, FEP, CX, SXT | |
| Transconjugant of EC11994 | 6.53 × 10−6 | blaSHV, blaCMY-2 | CTX, CAZ, CPD, ATM, CRO, FEP, CX, RD |
a The recipient was rifampicin-resistant E. coli K-12 MG1655 (F− λ− ilvG rfb-50 rph-1) having a cefotaxime MIC of 0.125 μg/mL. AMC: amoxycillin/clavulanate; CX: cefoxitin; ATM: aztreonam; CTX: cefotaxime; CAZ: ceftazidime; CRO: ceftriaxone; CPD: cefpodoxime; FEP: cefepime; IPM: imipenem; MEM: meropenem; CIP: ciprofloxacin; DO: doxycycline; CN: gentamicin; SXT: sulfamethoxazole/ trimethoprim; RD: rifampicin.