Kinetic parameters of lithocholic acid metabolite formation by human hepatic microsomes
Kinetic parameters were derived from the metabolite formation data presented in Fig. 2. Values represent the mean ± S.E.M. of triplicate determinations. Kinetic parameters of hepatic microsomal metabolite formation were calculated using the Michaelis-Menten equation for all five metabolites.
Metabolite | Apparent Vmax | Apparent Km | Vmax/Km Ratio |
|---|---|---|---|
| pmol/min/mg protein | μM | ||
| 3-Ketocholanoic acid | 336.2 ± 13.6 | 21.9 ± 2.6 | 15.3 ± 0.3 |
| Hyodeoxycholic acid | 47.5 ± 4.3 | 46.3 ± 13.3 | 1.0 ± 0.1 |
| Ursodeoxycholic acid | 14.6 ± 0.6 | 32.6 ± 5.2 | 0.4 ± 0.0 |
| Murideoxycholic acid | 5.5 ± 0.2 | 18.2 ± 3.2 | 0.3 ± 0.0 |
| 6-Ketolithocholic acid | 4.7 ± 0.2 | 39.4 ± 4.8 | 0.1 ± 0.0 |