FIGURE 1.

H₂S metabolism in human RBCs. A, Western blot analysis of RBC samples (200 μg of Hb/lane) and human recombinant MST, CBS, and CSE standards indicate the presence of MST but not the other two H₂S-generating enzymes. Lanes 1, 2, and 3 contain samples, molecular weight standards, and purified proteins, respectively. B and C, kinetics of H₂S clearance by a 10% (v/v) suspension of human RBCs in PBS, pH 7.4, 25 °C (B) and by human MetHb (0.5 mg ml⁻¹) in 100 mm HEPES, pH 7.4, 25 °C (C) under aerobic (–●–) or anaerobic conditions (–○–). The data presented in B and C represent the mean ± S.D. of three independent experiments.