Table 2

Hydrolytic efficiencies of representative carbapenemase variants against various β-lactam substrates

β-LactamaseHydrolytic efficiency (kcat/Km ) (s−1 μM−1)a against: Reference
ImipenemMeropenemCeftazidimeCefotaximeAztreonamCefoxitinCephalothinPenicillin G
KPC-20.290.27ND0.100.080.0020.841.90 271
KPC-31.901.400.030.50ND0.503.50ND 4
VIM-10.130.260.080.680.205.100.04 93
VIM-23.802.500.055.801.2011.84.0 74
VIM-423.00.90NDNDND36.03.10 137
VIM-50.290.050.0010.09NDND0.26 95
VIM-196.02.00.0230.00.50ND5.0 227
VIM-270.26NDND0.820.038.30ND 198
IMP-11.200.120.180.352.02.400.62 136
IMP-40.350.180.070.14ND0.430.08 51
NDM-10.210.250.030.580.020.400.68 273
NDM-40.460.310.061.200.50ND 189
OXA-480.14<0.0010.0010.05ND0.156.10 217
  • ND, not determined; —, no hydrolysis detected.