Table 3.
Steady-state kinetics of incorporation of dCTP and dATP opposite G and 8-oxoG bases by Dbh and the variants
| pol | Template base | dNTP | Km (μM)(a) | Vmax (nMmin−1)(a) | Vmax/Km (min) |
|---|---|---|---|---|---|
| Dbh | G | dCTP | 88.2 ± 12.0 | 1.0 ± 0.1 | 11 |
| dATP | 215.2 ± 18.7 | 0.019 ± 0.001 | 0.088 | ||
| 8-oxoG | dCTP | 67.7 ± 6.3 | 0.5 ± 0.02 | 7.4 | |
| dATP | 139.8 ± 3.1 | 0.18 ± 0.002 | 1.3 | ||
| Sdbh | G | dCTP | 75.2 ± 12.0 | 1.4 ± 0.1 | 19 |
| dATP | 128.4 ± 26.3 | 0.04 ± 0.003 | 0.31 | ||
| 8-oxoG | dCTP | 59.6 ± 11.1 | 0.61 ± 0.07 | 10 | |
| dATP | 114.9 ± 27.8 | 0.23 ± 0.009 | 2.0 | ||
| SdbhM76I | G | dCTP | 54.9 ± 8.6 | 1.9 ± 0.2 | 35 |
| dATP | 76.7 ± 7.1 | 0.08 ± 0.01 | 0.10 | ||
| 8-oxoG | dCTP | 55.5 ± 4.9 | 1.0 ± 0.05 | 18 | |
| dATP | 69.1 ± 9.3 | 0.4 ± 0.05 | 5.8 | ||
| SdbhKSKIP 241–245RVRKS | G | dCTP | 40.1 ± 5.2 | 2.3 ± 0.1 | 57 |
| dATP | 71.7 ± 9.6 | 0.16 ± 0.02 | 0.22 | ||
| 8-oxoG | dCTP | 33.5 ± 2.7 | 1.0 ± 0.04 | 30 | |
| dATP | 55.1 ± 2.9 | 0.5 ± 0.04 | 9.1 |
(a)The values of Vmax and Km were fit by nonlinear regression of the Michaelis-Menten equation. All reactions were done in duplicate, and the indicated data points are shown as the mean ± standard deviation.