The estimated kinetic parameters for glucuronidation of dopamine
The Km and KA values and the Vmax values of UGT1A10 and human intestinal microsomes are presented as best-fit values ± S.E. The Vmax values of the UGT1A10 mutants are normalized for their expression levels compared with wild-type recombinant UGT1A10. Enzyme kinetic parameters for human liver microsomes could not be determined because enzyme saturation could not be achieved at the highest substrate concentration tested.
Dopamine-3-O-Glucuronide | Dopamine-4-O-Glucuronide | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Km or KA | Vmax | n | Km or KA | Vmax | n | |||||
| μM | pmol/min/mg | μM | pmol/min/mg | |||||||
| 1A10a | 1950 ± 171 | 116 ± 4.89 | 1.52 | 2190 ± 205 | 140 ± 6.50 | 1.49 | ||||
| 10F90Aa | 1890 ± 211 | 6.62 | 1.50 | 1990 ± 240 | 3.38 | 1.65 | ||||
| 10F90La | 2590 ± 150 | 36.7 | 1.60 | 2310 ± 103 | 36.2 | 1.74 | ||||
| 10F93Ab | 2630 ± 353 | 14.9 | 2910 ± 352 | 13.0 | ||||||
| 10F93Lb | 3110 ± 479 | 15.8 | 2670 ± 344 | 54.1 | ||||||
| HIMa | 2870 ± 267 | 25.3 ± 1.13 | 1.26 | 3410 ± 398 | 28.1 ± 1.56 | 1.17 | ||||
| HLM | Could not be determined. | Could not be determined. |
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