Table 2.
Extension of DNA synthesis past an 8oxodG lesion
| Mutant polymerase | 8oxodG:dA | 8oxodG:dC | |||||
|---|---|---|---|---|---|---|---|
| Km (μM) | Kcat (min−1) | (Kcat/Km) (μM−1min−1) | Km (μM) | Kcat (min−1) | (Kcat/Km) (μM−1min−1) | fext | |
| PolwtExo− | 0.09 ± 0.01 | 0.15 | 1.70 | 1.08 ± 0.1 | 0.13 | 0.12 | 14.2 |
| PolY390FExo− | 2.86 ± 0.26 | 0.07 | 2.5 × 10−2 | 10.12 ± 1.73 | 0.10 | 5 × 10−3 | 5 |
| PolY390SExo− | 0.56 ± 0.05 | 0.13 | 0.23 | 3.85 ± 0.25 | 0.11 | 0.02 | 11.5 |
(Kcat/Km) stands for the catalytic efficiency displayed by mutant polymerases for extension of either 8oxodG:dA or 8oxodG:dA base pair. fext stands for extension discrimination factor obtained by dividing catalytic efficiency for the extension of 8oxodG:dA base pair by that for the extension of 8oxodG:dC base pair.