Table 2.

MICs for clinical strain E. coli Bre-1 and the corresponding transformants and recombinant clones

DrugbMIC (μg/ml)
E. coli Bre-1a (CTX-M-93)E. coli TOP10(pNBRE-1)E. coli TOP10(pM-93)E. coli TOP10(pM-27)E. coli TOP10(pM-93-Q169 M)E. coli TOP10(pM-27-L169C)E. coli TOP10
Amoxicillin644>2569684
Amoxicillin + CLA4444444
Ticarcillin422>256256162
Ticarcillin + CLA2224442
Piperacillin8248482431.5
Piperacillin + TZB1211111
Cefalothin1611>256160.50.5
Cefuroxime10.250.125>256>25660.25
Cefixime>25612860.560.750.25
Cefoxitin40.25110.510.25
Cefotaxime63132120.750.25
Ceftazidime81681.540.380.125
Ceftazidime + CLA0.250.50.250.1250.1250.1250.125
Cefpirome31.50.521.50.120.032
Cefepime0.750.380.1250.50.380.470.023
Imipenem0.190.190.190.190.190.190.19
  • a E. coli BRE-1 produced β-lactamase CTX-M-93.

  • b CLA, clavulanic acid at a fixed concentration of 2 μg/ml; TZB, tazobactam at a fixed concentration of 4 μg/ml.