FIGURE 3.

Inhibition of mCOX-2 active site mutants by naproxen and nonselective NSAIDs. A, naproxen (0.25–25 μm) was preincubated with WT mCOX-2 (○) or R120A (▴), R120Q (▵), and Y355F (♦) mCOX-2 mutant enzymes for 20 min prior to the addition of substrate (50 μm) for 30 s at 37 °C. B, naproxen (●), indomethacin (■), diclofenac (▴), or flurbiprofen (♦) was preincubated with mCOX-2 W387F for 20 min prior to the addition of substrate (50 μm). Inhibitor concentrations ranged from 0.25 to 25 μm. Each reaction was terminated and substrate consumption was analyzed by TLC as described. Data points represent the mean of duplicate determinations. Data points for naproxen against W387F represent the mean of five independent experiments in duplicate. Error bars, S.E.