TABLE 3.

Kinetic parameters of AmpC M29 from Morganella morganii strain PP29 with different substrates

Substrate	Km (μM)	kcat (s−1)	kcat/Km (μM−1 · s−1)
Benzylpenicillina	0.25 ± 0.007	0.0074 ± 0.0004	0.03 ± 0.002
Ampicillina	0.13 ± 0.009	0.065 ± 0.003	0.5 ± 0.02
Piperacillina	0.17 ± 0.005	1.5 ± 0.08	9 ± 0.4
Oxacillina	0.003 ± 0.0003	0.022 ± 0.001	7 ± 0.3
Imipenema	2 ± 0.3	0.07 ± 0.003	0.035 ± 0.002
Nitrocefin	25 ± 4	93 ± 8	3.8 ± 0.3
Cephalothin	148 ± 10	140 ± 35	1 ± 0.2
Cefoxitina	0.018 ± 0.0015	0.038 ± 0.0018	2.1 ± 0.1
Cefotaximea	0.02 ± 0.0016	0.032 ± 0.002	1.6 ± 0.1
Ceftazidimea	0.9 ± 0.04	0.04 ± 0.002	0.045 ± 0.002
Cefepimea	95 ± 9	0.008 ± 0.0007	8 × 10−5 ± 7 × 10−6

^aFor these substrates, the K_m value was determined as a K_i value using nitrocefin as a reporter substrate.