TABLE 2.
Deuterium KIEs upon LA oxidation at 30 °C
Limiting deuterium KIEs are quoted with ±1 S.E. in parentheses.
| COX-2 | WT | WT(Mn(III))a | Y334F |
|---|---|---|---|
| Dkcatb | 21.4 (2.3) | 20.0 (3.0) | 29.6 (3.6) |
| Dkcat/Km(LA)b | 10.6 (1.9) | 8.0 (1.0) | 28.0 (3.4) |
| Dkcat/Km(LA)c | 8.7 (0.8) | 7.5 (1.0) | 25.0 (3.2) |
| Dkcat/Km(O2)b | 6.7 (1.4) | 11.0 (2.6) | 29.4 (4.2) |
a Mn(III)(Por)-reconstituted WT COX-2.
b Calculated from non-competitively determined rate constants.
c Determined competitively by UPLC-MS analysis of the products at <10% of the expected [O2] consumed as described under “Experimental Procedures.”