TABLE 2.

Kinetic parameters of the efflux process

Substrate$$mathtex$$\(\mathit{V}_{\mathit{e}}^{\mathit{max}}\)$$mathtex$$ (nmol/mg/s)Hill coefficientK0.5 (μM)Permeability coefficient (μm/s)Substituent log Pa
Dicloxacillin0.98, 0.95, 0.943.6, 4.7, 4.30.53, 0.83, 0.820.6, 0.6, 0.63.4
Cloxacillin0.89, 0.99, 0.802.3, 2.7, 2.40.95, 1.03, 0.910.6, 0.6, 0.62.8
Oxacillin0.94, 1.1, 0.942.6, 2.7, 2.61.04, 0.97, 1.030.6, 0.6, 0.62.1
Azlocillin0.42, 0.41, 0.354.0, 4.0, 4.61.08, 1.06, 1.090.4, 0.4, 0.40.71
Mezlocillin0.51, 0.47, 0.504.4, 4.5, 4.51.09, 1.08, 1.110.5, 0.5, 0.50.67
Piperacillin0.39, 0.35, 0.394.1, 3.7, 4.11.06, 1.08, 1.080.4, 0.4, 0.30.45
Penicillin V0.72, 0.85, 0.724.7, 4.7, 4.60.82, 0.84, 0.830.8, 0.7, 0.71.54
Ampicillin0.38, 0.37, 0.371.9, 2.3, 2.50.88, 0.92, 1.030.8, 0.8, 0.8−1.03