TABLE 3.
Activation parameters for AA and LA oxidation by WT and Y334F COX-2
Values in parentheses reflect ±1 S.E.
| Ea(H)a | Ea(D)a | AHb | ADb | |
|---|---|---|---|---|
| WT COX-2 + AA | ||||
| kcatc | 13.9 (0.9) | 15.4 (0.6) | 2.3 (5.5) × 1011 | 9.1 (4.1) × 1011 |
| kcat/Km(O2)d | 13.2 (1.4) | 15.2 (2.0) | 8.6 (30) × 1015 | 8.5 (13) × 1015 |
| WT COX-2 + LAe | ||||
| kcatc | 9.1 (0.2) | 9.1 (0.2) | 3.6 (1.2) × 107 | 1.8 (1.1) × 106 |
| kcat/Km(O2)d | 7.3 (0.6) | 12.3 (0.5) | 6.8 (2.7) × 1010 | 4.9 (2.8) × 1013 |
| Y334F COX-2 + LA | ||||
| kcatc | 6.7 (0.7) | 9.4 (0.7) | 4.6 (1.5) × 105 | 1.8 (0.8) × 106 |
| kcat/Km(O2)d | 5.7 (0.5) | 7.9 (0.3) | 5.6 (2.4) × 108 | 8.1 (1.2) × 108 |
a Units of kcal mol−1.
b The units are the same as those of the rate constants.
c Units of s−1.
d Units of m−1 s−1.
e From Ref. 5.