Table 2. Spectral Interaction of Acenaphthene, Acenaphthylene, 1-Acenaphthenol, and 1,2-Epoxyacenaphthene with P450s 2A6, 2A13, and 3A4^a.

P450		ace- naphthene	ace- naphthylene	1-acenaphthenol	1,2-epoxy- acenaphthene
P450 2A6	Ks (μM)	1.2±0.2	4.4±0.5	ND	1.78 ± 0.25
	ΔAmax	0.066±0.002	0.076±0.002		0.062 ± 0.002
	ΔAmax /Ks	0.055	0.017		0.035
P450 2A13	Ks (μM)	0.48±0.10	0.61±0.21	0.48±0.03	0.16±0.03
	ΔAmax	0.074±0.005	0.050±0.004	0.061±0.001	0.073 ± 0.002
	ΔAmax / Ks	0.15	0.081	0.13	0.46
P450 3A4	Ks (μM)	19±3.5	13±2.7	7.8 ± 2.2	6.20 ± 0.87
	ΔAmax	0.040±0.003	0.030±0.002	0.013 ± 0.001	0.041 ± 0.002
	ΔAmax / Ks	0.002	0.002	0.002	0.007

^aThe results for K_s and ΔA_max values indicate SE, obtained from fitting of hyperbolic plots in GraphPad Prism, and values for ΔA_max / K_s include further analysis of the SE of the quotients. ND, not detected even at concentration of 16 μM.