Figure 2.

Inhibition of TGase activity by aspirin is time dependent. Recombinant TGM2 (0.7 μM) was incubated with 500 μM of ASA in HEPES-buffered saline (HBS; 50 mM HEPES, pH 8.5, 100 mM NaCl) at room temperature for 0.5, 1, 2, 3, 4, and 16 hours. Following reaction, the reaction mixtures were dialyzed against large excess of dialysis buffer containing 10 mM Tris-Cl, pH 7.5, 10% glycerol, and 1 mM EDTA. After dialysis, equal amounts (∼2 μg) of acetylated TGM2 were loaded on 8–15% SDS-PAGE gel and stained with Coomassie blue (bottom panel). TGase activity was measured using the established BP incorporation assay.¹⁹ The data represent the average (±standard deviation) of a total of three independent experiments.