Table 2.

Steady-state kinetic constants of recombinant L1 and other metallo-β-lactamases isolated from S. maltophilia in cacodylate buffer

CompoundRecombinant L1aMetallo-β-lactamase isolated from S. maltophilia
Km (μM)kcat(s−1)Km (μM)kcat (s−1)Reference
Piperacillin38 ± 3440 ± 1020 ± 1140 10
Ampicillin55 ± 5520 ± 1040 ± 3175 10
BRL42715240 ± 20210 ± 10270 ± 100.55 16
Penicillin G22 ± 3480 ± 1050 ± 61,100 10
Nitrocefin4 ± 141 ± 17 ± 120 10
  • a The buffer used for studies with recombinant L1 was 50 mM sodium cacodylate, pH 7.0, containing 100 μM Zn(II) at 25°C.