Figure 1.
Concentrations of the nitrite species (A) 16 O = N-16O‒, (B) 16 O = N-18O‒ and 18 O = N-16O‒, and (C) 18 O = N-18O‒ upon incubation of sodium nitrite (100 µM) with bovine erythrocytic CA II (5 mg/mL, 172 µM) and acetazolamide (0, 25, 50, 100, 200 µM) for 10 min in 100 mM Tris buffer, pH 7.4, prepared in 18 O-water (>98% 18 O). The experiment was performed as described elsewhere3. Data are shown as mean with standard deviation from separate quadruplicate incubations. Statistical analysis was performed by one-way ANOVA and Mann-Whitney test.