Table 4.

Kinetic parameters of SFO-1 and FEC-1 for β-lactam antibiotics

SubstrateSFO-1FEC-1
Km (μM)Relative VmaxaRelative Vmax/ KmaKm(μM)Relative VmaxaRelative Vmax/ Kma
Cephaloridine110100100152100100
Cephalothin60234428134198225
Cefamandole171241154122125156
Cefotiam27502033843170
Cefoperazone6.6152462.82.6139
Cefpiramide26712973336167
Cefuroxime13231952732179
Ceftizoxime217125.8821122.3
Cefotaxime2.216790612359
Cefmenoxime21201088461110
Ceftriaxone191584271480
Ceftazidime7850.470.0653930.130.05
Ampicillin401951301789
  • a Values relative to that for hydrolysis of cephaloridine, which was set equal to 100.