Table 3. Use of alternative nucleotide triphosphates by recombinant Arabidopsis NADHK.
Assays were conducted using the standard assay mixture (pH 7.9, 25 °C), except that the NDP concentration was varied in the presence of either 0.8 mM NADH or 4 mM NAD+. Abbreviation: n/d, not detected.
| Vmax/Km (units·mg−1·mM−1) | |||||
|---|---|---|---|---|---|
| Nucleotide or phosphate | Nicotinamide nucleotide | Vmax (units·mg−1) | Km (mM) | NADH | NAD+ |
| ATP | NADH | 39.5±0.9 | 0.062±0.002 | 637 | − |
| NAD+ | 20.3±0.7 | 0.190±0.008 | − | 107 | |
| UTP | NADH | 22.6±0.1 | 0.156±0.005 | 145 | − |
| NAD+ | 11.5±0.1 | 0.885±0.020 | − | 13 | |
| GTP | NADH | 16.3±1.0 | 0.461±0.021 | 35 | − |
| NAD+ | 2.4±0.2 | − | − | − | |
| CTP | NADH | 13.8±0.6 | 0.759±0.01 | 18 | − |
| NAD+ | 2.0±0.1 | − | − | − | |
| PPi | NAD(H) | n/d | − | − | − |
| Poly- Pi | NAD(H) | n/d | − | − | − |