TABLE 1

The kinetic constants for the inactivation of P450 enzymes by BG

The catalytic activities of P450s 2B1, 2B4, and 2B6 were assessed using the EFC O-deethylation assay (-b5), and the catalytic activity of P450 3A5 (+b5) was determined using the testosterone 6β-hydroxylation assay. The data shown represent the mean values from at least two separate experiments with duplicate samples.


P450

KI

kinact

t1/2

kinact/KI
μM min-1 min min-1 mM-1
2B6 5.2 0.087 8 17
3A5 20 0.045 15 2
2B1 2.4 0.049 14 20
2B4
2.8
0.068
10
24