TABLE 4.

Cytochrome P450 content of microsomes^a

Vector	CYP52A gene	ΔA450 − A490	Concn of CYP52Ab (μM)
pFastBac Dual	None	0.0003
pFBDncp2A	CYP52A13	0.0094	0.52
pFBDncp5A	CYP52A17	0.0137	0.75

^aCytochrome P450 content of microsomes was estimated by reduced CO difference spectra of microsomes treated with CO and dithionite as described in Materials and Methods. Vector constructs are described in Table 1.

^bThe concentration of functional cytochrome P450 in the original, undiluted microsomal samples was calculated with an extinction coefficient of 91 mM⁻¹ cm⁻¹.