Table 3.
Kinetic parameters of dNTP or rNTP incorporation into RNA by Polη.
| Insertion opposite | Incoming nucleotide | kcat (min−1) | Km (µM) | kcat/Km | nucleotide concentrationa (µM) | Relative frequency |
|---|---|---|---|---|---|---|
| T | dATP | 15.607 ± 1.227 | 158.94 ± 39.16 | 98.19 E-03 | 16 | 1.02 |
| T | rATP | 0.2394 ± 0.0065 | 466.4 ± 47.29 | 0.51 E-03 | 3000 | |
| G | dCTP | 12.085 ± 0.786 | 107.7 ± 24.7 | 112.20 E-03 | 14 | 0.52 |
| G | rCTP | 2.758 ± 0.062 | 438.3 ± 37.52 | 6.29 E-03 | 500 | |
| C | dGTP | 6.9332 ± 0.2768 | 44.35 ± 7.92 | 156.31 E-03 | 12 | 2.35 |
| C | rGTP | 0.4487 ± 0.0149 | 393.7 ± 52.04 | 1.14 E-03 | 700 | |
| A | dTTP | 7.5753 ± 0.5505 | 174.49 ± 38.01 | 43.41 E-03 | 30 | 3.14 |
| A | rUTP | 0.1032 ± 0.0057 | 423.3 ± 90.45 | 0.24 E-03 | 1700 |
a In vivo dNTP and rNTP concentrations are according to ref.14.
Values were obtained from results shown in Figs 2 and 3, and represent the mean and standard error of at least three experiments. Relative frequency of incorporation was calculated using the following equation: f rel = (kcat1 /Km1) * [dNTP]/(kcat2/Km2) * [rNTP], where kcat1/Km1 is the value for dNTP incorporation and kcat2/Km2 is the one for rNTP incorporation.