TABLE 2.

Kinetic parameters for the purified OXA-32 β-lactamasea

SubstratekcatKm (μM)kcat/Km
Benzylpenicillin3.54580
Cloxacillin2.511020
Amoxicillin1.522070
Ticarcillin16015
Piperacillin315520
Cephalothin36050
Cephaloridine23606
Cefotaximeb
CeftazidimeHc>3,000H
Cefpirome
Aztreonam
  • a Data are the means of three independent experiments. Standard deviations were within 10%.

  • b —, no detectable hydrolysis.

  • c H, hydrolyzed, but kinetic parameters could not be determined due to high Km value.