Table I.
Catalytic parameters of WT Prx Q versus various hydroperoxides These parameters were determined by following the NADPH oxidation in the presence of 1 μm WT Prx Q. The apparent Km for the various hydroperoxides was measured at saturating concentrations of Trx h3. The Km of Prx Q for Trx h3 is 1.5 μm.
| kcat | Km | kcat/Km | Vmax | |
|---|---|---|---|---|
| s-1 | μm | × 103 m-1s-1 | μmol NADPH ox min-1 μmol-1 | |
| H2O2 | 2.93 | 367 ± 37.5 | 7.98 | 176 (10.46)a |
| tBOOH | 0.896 | 375.2 ± 125.7 | 2.39 | 53.76 (3.19)b |
| CUOOH | 2.35 | 98.8 ± 19.1 | 23.78 | 141.12 (8.38)c |
a
No. in parentheses is μmol NADPH ox min-1 mg-1 protein