TABLE 2

Kinetic parameters of TEM-184 compared with TEM-1, TEM-10, TEM-87, TEM-107, and TEM-149 ESBLs

SubstrateTEM-184 (Q6K, E104K, I127V, R164S, M182T)aTEM-1bTEM-10b (R164S, E240K)TEM-87c (E104K, R164C, M182T)TEM-107d (E104K, R164H, M182T, G238S)TEM-149e (E104K, R164S, M182T, E240V)
Km (μM)fkcat (s−1)kcat/Km (μM−1 s−1)Km (μM)kcat (s−1)kcat/Km (μM−1 s−1)Km (μM)kcat (s−1)kcat/Km (μM−1 s−1)Km (μM)kcat (s−1)kcat/Km (μM−1 s−1)Km (μM)kcat (s−1)kcat/Km (μM−1 s−1)Km (μM)kcat (s−1)kcat/Km (μM−1 s−1)
Cefazolin98 ± 840.045132000.3941712.50.0354 ± 2130.24NANANA68 ± 52.20.03
Cefotaxime44 ± 320.046,0009.01.5 × 10−3300.30.0153 ± 32.20.042230.1443 ± 20.071.6 × 10−3
Ceftazidime333 ± 18530.164,2800.30.7 × 10−4607170.0394 ± 5230.2486150.1719 ± 18.30.44
Cefepime400 ± 2540.01NAfNANANANANA23 ± 14.40.192630.1116 ± 12.40.15
Aztreonam21 ± 1.5130.621,4301.06.9 × 10−42820.0750 ± 15.30.111720.1251 ± 34.70.09
Piperacillin192 ± 15270.14NANANANANANA14 ± 1705.03113.671.4g ± 0.32.71.92
Benzylpenicillin68 ± 7240.35251,60064.025125.506.2 ± 0.5396.29NANANA0.6g ± 0.053.55.80
Carbenicillin29 ± 2220.76NANANANANANA1.5 ± 0.56.72.24NANANANANANA
Nitrocefin190 ± 101,4707.745593016.947591.2516 ± 2311.9457214.420 ± 27.40.37
  • a Each kinetic value is the mean of three different measurements; the error was below 10%.

  • b Data from Raquet et al. (18).

  • c Data from Perilli et al. (10).

  • d Data from Lee et al. (11).

  • e Data from Perilli et al. (12).

  • f NA, not available.

  • g Km was calculated as Ki using nitrocefin as reporter substrate (9).