Formation of C-7 and loss of substrate in incubations of [14C]laromustine (25 and 100 μM) with various recombinant human P450 enzymes (25 pmol/incubation) expressed in Escherichia coli (bactosomes)
Pmol values are the mean of duplicate determinations and are rounded to three significant figures. Percent values are rounded to one decimal place. From Nassar et al. (2009).
| Recombinant Human P450 Enzyme | Incubation Time | [14C]Laromustine | C-7 Formed per Incubation | [14C]Laromustine Detected per Incubation | Percent Loss of substratea |
|---|---|---|---|---|---|
| min | μ M | pmol | pmol | % | |
| Bactosome control | 10 | 25 | NC | 5380 | 17.9% |
| Reductase control | NC | 5390 | 17.7% | ||
| rCYP1A2 | NC | 5560 | 15.0% | ||
| rCYP2B6 | 376 | 5270 | 19.5% | ||
| rCYP2D6 | NC | 5470 | 16.5% | ||
| Bactosome control | 100 | NC | 20100 | 14.7% | |
| Reductase control | NC | 20400 | 13.6% | ||
| rCYP1A2 | NC | 20300 | 13.9% | ||
| rCYP2B6 | 513 | 20000 | 15.3% | ||
| rCYP2D6 | NC | 20100 | 14.6% |
NC, not calculated (represents a zero or negative value beyond the AUC level).
↵a Percent loss of substrate was determined on the basis of the zero-minute microsomal sample.