Table 2.
Kinetic parameters for wild-type and S276A nitroalkane oxidase.
| Substrate | Kinetic parameter | Wild-type NAO | S276A NAO |
|---|---|---|---|
| Nitroethanea | kcat(nitroethane) (s−1) | 15 ± 1 | 1.0 ± 0.01 |
| kcat/K(nitroethane) (mM−1s−1) | 6.3 ± 0.4 | 0.30 ± 0.02 | |
| K(nitroethane) (mM) | 2.3 ± 0.2 | 3.3 ± 0.2 | |
| Ki(nitroethane) (mM) | 25 ± 3 | - | |
| D(kcat/Km) | 9.2 ± 1.1 | 9.7 ± 2.0 | |
| Dkcat(nitroethane) | 1.4 ± 0.2 | 2.1 ± 0.4 | |
| kred (s−1) | 247 ± 5 | 3.4 ± 0.4 | |
| 1-nitrohexane | kcat(nitrohexane) (s−1) | 2.0 ± 0.1 | 0.30 ± 0.006 |
| kcat/Knitrohexane (mM−1s−1) | 47 ± 10 | 1.5 ± 0.2 | |
| Knitrohexane (mM) | 0.04 ± 0.01 | 0.20 ± 0.02 | |
| Ki(nitrohexane) (mM) | - | 130 ± 25 | |
| 1-nitrooctane | kcat(nitrooctane) (s−1) | 4.4 ± 0.4 | 0.2 ± 0.01 |
| kcat/K nitrooctane (mM−1 s−1) | 150 ± 46 | 1.3 ± 0.2 | |
| K nitrooctane (mM) | 0.03 ± 0.01 | 0.3 ± 0.02 | |
| Ki(nitrooctane) (mM) | 8.3 ± 3.7 | 26 ± 5 |
a
Data for the wild-type enzyme are from Valley and Fitzpatrick (3).