Table 2

Kinetic parameters of chlorzoxazone 6-hydroxylation by recombinant CYP2Es

	Human		Canine
	CYP2E Tyr₄₈₅^2-a	CYP2E His₄₈₅^2-a	CYP2E1^2-a
K _m (mM)	0.131 ± 0.034	0.127 ± 0.030	0.035 ± 0.010
V _max (nmol 6-OH-CZX/min/nmol)	8.2 ± 1.9	8.7 ± 2.4	9.8 ± 0.3
Intrinsic clearance (V _max/K _m)	67 ± 25	73 ± 31	293 ± 73

cDNAs were expressed in a bacterial cDNA expression system, and recombinant protein partially purified as described in Materials and Methods

↵2-a Results are expressed as mean ± S.D. of triplicate experiments.