Kinetic analysis of UGTs expressed in SF-9 and COS-1 cells
| Enzyme | KM | Vmax |
|---|---|---|
| μM | pmol/min/mg protein | |
| UGT1A6 (SF-9) | ||
| 4-Nitrophenol | 100 | 1250 |
| 2-OH-biphenyl | 138 | 890 |
| UGT1A6 (COS-1) | ||
| 4-Nitrophenol | 160 | 100 |
| 2-OH-biphenyl | 140 | 85 |
| UGT2B13 (SF-9) | ||
| Octylgallate | 225 | 850 |
| 4-OH-biphenyl | 290 | 910 |
| UGT2B13 (COS-1) | ||
| Octylgallate | 208 | 153 |
| 4-OH-biphenyl | 333 | 200 |
UGT activities were performed with substrates ranging from 10 μM to 1 mM final concentrations, with a UDPGA concentration of 100 μM. For COS-1 cell extracts, 50 μg of protein was used. For SF-9 cell extracts, 10 μg of protein was used. Each assay was incubated for 1 hr. Activities at each substrate concentration were performed in duplicate. OH, hydroxy.