Figure 4. Pyruvate and H₂O₂ Produce Acetate.

(A) One mM H₂O₂ was added to pyruvate-free BSK-II and standard BSK-II and H₂O₂ was measured over time using the xylenol orange/ferric iron assay [52]. (B) One mM pyruvate was added to pyruvate-free BSK-II. H₂O₂ (7 mM) was added and pyruvate was measured over time using a commerically available kit. Data shown are mean +/− SD (n = 3). The half-life values, in minutes, are shown in parentheses. (C) Production of acetate by pyruvate and H₂O₂ requires both reactants in BSK-II medium. The production of acetate was measured over time in BSK-II medium that contained pyruvate (7 mM), lacked pyruvate, and contained pyruvate with the addition of bovine catalase (200 U ml⁻¹).