TABLE 1.

MICs of β-lactams for clinical isolate P. aeruginosa CY-1, P. aeruginosa PU21 harboring natural plasmid pGER-1, reference strain P. aeruginosa PU21, E. coli DH10B harboring recombinant plasmids pPG13 and pPG14, and reference strain E. coli DH10B

β-Lactam(s)aMIC (μg/ml)
P. aeruginosa CY-1 (OXA-32)P. aeruginosa PU21(pGER-1)(OXA-32)P. aeruginosa PU21E. coli DH10B(pPG13) (OXA-32)E. coli DH10B(pPG14) (OXA-2)E. coli DH10B
Amoxicillin>512>512>512256>5124
Amoxicillin + CLA>512>512>51216644
Ticarcillin642568128>5124
Ticarcillin + CLA3264416324
Piperacillin1632864641
Piperacillin + TZB41616821
Cephalothin>512>512>51216642
Cefsulodin3232216162
Ceftazidime12812813240.5
Ceftazidime + CLA1281288160.50.5
Cefotaxime81680.50.120.06
Cefepime8810.250.060.06
Cefpirome321640.50.060.06
Moxalactam326480.50.120.12
Aztreonam1632420.120.12
Imipenem8420.120.120.12
  • a CLA, clavulanic acid at a fixed concentration of 2 μg/ml; TZB, tazobactam at a fixed concentration of 4 μg/ml.