TABLE 3.
Steady-state kinetics parameters and drug inhibition of the wild type and recombinant DNA pol mutants exhibiting resistance to foscarneta
| Recombinant protein | Steady-state kinetics parameters |
Inhibition by PFA |
||||
|---|---|---|---|---|---|---|
| Vmax(app) (fmol/min) | Km(app) (μM) | Vmax(app)/ Km(app) | Fold changeb | Ki(app) (μM)c | Fold changeb | |
| UL30-WT | 26.39 ± 1.6 | 0.98 ± 0.27 | 27.04 | 1.00 | 0.22 ± 0.07 | 1.00 |
| UL30-I619K | 27.7 ± 11.96 ns | 2.45 ± 1.19 ns | 11.30 | 0.42 | 0.97 ± 0.28* | 4.6 |
| UL30-A719T | 71.2 ± 11.09** | 2.71 ± 0.85 ns | 26.29 | 0.97 | 1.08 ± 0.54* | 5.0 |
| UL54-WT | 5.41 ± 2.47 | 0.60 ± 0.16 | 8.98 | 1.00 | 0.25 ± 0.04 | 1.00 |
| UL54-Q697P | 9.30 ± 4.37 ns | 3.5 ± 0.14* | 2.7 | 0.29 | 0.83 ± 0.08** | 3.4 |
| UL54-A719T | 22.7 ± 9.1* | 3.5 ± 1.2* | 6.5 | 0.72 | 1.1 ± 0.15** | 4.6 |
a
WT, wild type; Vmax(app), apparent maximum velocity; Km(app), apparent Michaelis-Menten constant; Ki(app), apparent constant of inhibition. A one-way ANOVA with Dunnett’s posttest (GraphPad Prism, version 8.00) was used to compare the enzymatic parameters of mutant proteins to those of the WT. *, P < 0.05; **, P < 0.01; ns, nonsignificant compared to WT. Results are means ± SD from 3 independent experiments.
b
Fold change compared to WT values.
c
Ki values that are significantly different from those of the WT were considered to induce drug resistance.