TABLE 1.
Steady-state kinetic analysis of the effects of bithionol and GW5074 on the oxidative deamination reaction
The NAD-varied data is derived from linear regression analysis of the Lineweaver-Burk plots, whereas the glutamate-varied data were fitted to Equation 1 using non-linear regression analysis, where Ki is not the apparent binding constant for the drug but rather the concentration of glutamate necessary to yield half-maximal substrate inhibition under these conditions.
| Effects of drugs on the kinetic parameters for NAD+ | ||||
|---|---|---|---|---|
| [Bithionol] | 0 μm | 3 μm | 5 μm | 9 μm |
| Km (mm) | 0.31 (0.02) mm | 0.43 (0.06) mm | 0.36 (0.03) mm | 0.26 (0.02) mm |
| Vmax | 0.24 (0.005) | 0.22 (0.01) | 0.13 (0.004) | 0.05 (0.01) |
| R2 | 0.99 | 0.98 | 0.99 | 0.97 |
| [GW5074] | 0 μm | 1.5 μm | 4 μm | 8 μm |
| Km (mm) | 0.31 (0.01)mm | 0.23 (0.004) mm | 0.26 (0.006) mm | 0.14 (0.012) mm |
| Vmax | 0.24 (0.006) | 0.13 (0.003) | 0.09 (0.003) | 0.04 (0.001) |
| R2 | 0.99 | 0.98 | 0.97 | 0.91 |
| Effects of drugs on the kinetic parameters for glutamate | ||||
|---|---|---|---|---|
| [Bithionol] | 0 μm | 3 μm | 5 μm | 9 μm |
| Km (mm) | 1.62 (0.12) mm | 1.17 (0.1) mm | 1.06 (0.12) mm | 0.39 (0.10) mm |
| Vmax | 0.18 (0.003) | 0.14 (0.003) | 0.10 (0.003) | 0.05 (0.001) |
| Ki (shared) | 241 (17) mm | 241 (17) mm | 241 (17) mm | 241 (17) mm |
| R2 | 0.98 | 0.99 | 0.97 | 0.95 |
| [GW5074] | 0 μm | 1.5 μm | 4 μm | 8 μm |
| Km (mm) | 1.38 (0.12) mm | 1.38 (0.10) mm | 1.53 (0.12) mm | 1.27 (0.10) mm |
| Vmax | 0.17 (0.003) | 0.13 (0.003) | 0.09 (0.003) | 0.05 (0.002) |
| Ki (shared) | 350 (17) mm | 350 (17) mm | 350 (17) mm | 350 (17) mm |
| R2 | 0.99 | 0.98 | 0.99 | 0.99 |