Table I.
CYP76B1-dependent metabolism of xenobiotics
| Strain | NADPH | Activity
|
|||||
|---|---|---|---|---|---|---|---|
| MCOD | ECOD | MROD | EROD | CTUDM | IPUDM | ||
| pkat mg−1 protein | |||||||
| Control | + | n.d.a | n.d. | n.d. | n.d. | n.d. | n.d. |
| W(R) | + | 10.9 ± 0.3 | 8.4 ± 1.5 | 12.6 ± 1.6 | 5.1 ± 0.2 | 1223 ± 63 | 128 ± 2 |
| WAT11 | + | 16.4 ± 0.4 | 15.9 ± 0.25 | 18.6 ± 0.6 | 11.6 ± 0.8 | 4258 ± 24 | 475 ± 3 |
| WAT11 | − | n.d. | n.d. | n.d. | n.d. | n.d. | n.d. |
MCOD, ECOD, MROD, and EROD activities were determined fluorometrically using 16 pmol of CYP76B1 per 2-mL assay. Demethylation of CTUDM and IPUDM was tested using 14C-labeled substrates with approximately 3 pmol of CYP76B1 in the 200-μL assays. Conversion was estimated from the sum of the two polar metabolites detected after TLC analysis. Data are means ± sd of two to four determinations.
a
n.d., Not detected.