TABLE 1.
Steady-state catalytic activities of nNOS and the Lys842 mutants
Rates were measured at 25 °C as described under “Experimental Procedures.” Values represent the mean ± S.D. of three independent measurements with two preparations of each enzyme. ND, not detected.
| Enzyme | CaM | NO synthesis | NADPH Oxidation | Cytochrome c reduction | K3Fe(CN)6 reductase |
|---|---|---|---|---|---|
| min−1 | min−1 | min−1 | min−1 | ||
| nNOS WT | + | 42 ± 2.9 | 168 ± 2.2 | 4941 ± 100 | 10486 ± 796 |
| − | ND | 4.6 ± 0.1 | 511 ± 13 | 7825 ± 252 | |
| K842A | + | 32 ± 2.2 | 114 ± 2.1 | 3417 ± 12 | 9098 ± 314 |
| − | ND | 18 ± 0.2 | 754 ± 38 | 7294 ± 209 | |
| K842E | + | 40 ± 1.5 | 186 ± 0.5 | 4547 ± 220 | 10087 ± 283 |
| − | ND | 23 ± 0.2 | 1471 ± 81 | 7104 ± 265 |