TABLE 3

Rates of benzphetamine binding to native and PCP-inactivated P450 2B6

The inactivation of P450 2B6 and the stopped-flow studies to determine the rates of benzphetamine binding were performed as described under Materials and Methods.

P450 2B6	Phase 1			Phase 2			Σ k_n^b	Percentage of Native
P450 2B6		A₁^a	k₁	A₂	k₂		Σ k_n^b	Percentage of Native
	%	s^-1	%	s^-1	%_n	%
Native	58	8.0 ± 1	42	0.3 ± 0.01	4.8	100
Inactivated	30	5.0 ± 0.6	70	0.02 ± 0.003	1.5	31

↵ a Percentage of the change in amplitude is of the total change in amplitude [A_n/(A₁ + A₂)] × 100.
↵ b Σ k_n (%_n) is defined as Σ [(k_n)(% in phase n)] and is the summation of [(k₁)(% in phase 1)] + [(k₂)(% in phase 2)]. The data represent the averages and S.D. of three shots.