TABLE 1.

Characteristics of the strains used in this study

StrainpIKPC-2 PCRPlasmid(s) (kb)MIC (μg/ml) ofa:IMI hydro- lysisc
IMICPDCPD/CV4CAZCAZ/CV4FEPFEP/CV10FOXATM
Enterobacter sp. strain MGH 2219.2, 6.9, 5.4+65, 9, 4.8, 48>128>32>128>32328>16>12837.59
E. coli J53AzRNDbNone0.2520.50.120.25≤0.06≤0.03≤4<1ND
E. coli J53AzR/KPC-26.9, 5.4+65132440.52≤0.0383217.08
  • a IMI, imipenem; CPD, cefpodoxime; CPD/CV4, cefpodoxine-4 μg of clavulanate/ml; CAZ, ceftazidime; CAZ/CV4, ceftazidime-4 μg of clavulanate/ml; FEP, cefepime; FEP/CV10, cefepime-10 μg of clavulanate; FOX, cefoxitin; ATM, aztreonam.

  • b ND, not determined.

  • c Nanomoles of imipenem per minute per milligram of protein.