Table 3

Glucuronidation of phenols and coumarins by stably expressed human UGT1A8 and 1A10

SubstratesGlucuronide Formation
pmol/min/mg protein
Phenolic compounds
 4-Hydroxybiphenyl1200 19
 Mycophenolic acid1990 93
 4-Methylumbelliferone1180 26

Assays were performed using pH 7.4 Tris buffer at 37°C for 1.0 h and membrane preparations of HK293 cells expressing UGT1A8 or UGT1A10. The concentration of UDP-glucuronic acid was 2.0 mM and the aglycone concentrations were 0.5 mM. Values represent the average enzymatic rates from two different experiments.

  • ND, not detected (limit of detection is 2.0 pmol/min/mg protein).