Table 3.

MICs and enzymatic kinetic parameters for the clinicalE. coli isolates

Clinical isolatepIMIC (μg/ml)Penicillin GResidual activity (%)
AmoxicillinPiperacillin
AloneWith CaaAloneWith TazbKm (μM)Sp act (mU/mg)
AP15.42,04832641253359.5
AP25.4>4,0962561,02432251,7869.3
AP35.42,048326412758610
AP47.44,09612825632561NDc
AP55.42,048512324714456
AP65.24,0962,04812841383,20046.5
AP75.21,0242568121692533
AP85.22,0481,02432223266032.5
  • a Ca, clavulanic acid at 2 μg/ml.

  • b Taz, tazobactam at 4 μg/ml.

  • c ND, not determined (the enzyme was unstable).