TABLE 1

Kinetic parameters for the formation of 8-hydroxyefavirenz (MI) and 7-hydroxyefavirenz (MII) from efavirenz in two HLMs

Kinetic parameters for the formation of 8-hydroxyefavirenz were estimated by fitting the velocity vs. substrate concentrations to the Hill equation and for the formation of 7-hydroxyefavirenz using a single-site Michaelis-Menten equation. Apparent kinetic parameters (standard errors of parameter estimates) are presented.


Kinetic Parameters

HL9

HL9/14/99
MI
MII
MI
MII
Vmax (pmol/min/mg protein) 122.4 (3.9) 5.5 (0.2) 157.4 (4.7) 32.5 (3.5)
Km (μM) 17.4 (1.5) 13.1 (1.8) 22.9 (1.2) 66.6 (13.9)
Hill coefficient 1.33 (0.1) 1.7 (0.1)
Vmax/Km (μl/min/mg protein)
7.0
0.4
6.9
0.5