FIG. 6.

Peroxide consumption by H. pylori AhpC. The disappearance of peroxide was monitored by ferrithiocyanate complex formation following incubations of a mixture containing 20 μM AhpC (triangles) or 0 μM AhpC (circles) with TrxR (0.2 μM), Trx1 (2.0 μM), and an NADPH-regenerating system consisting of glucose-6-phosphate (10 mM), glucose-6-phosphate dehydrogenase (0.2 U/ml), and NADPH (10 μM) in 500-μl volumes. All reactions were started with the addition of H₂O₂ (1 mM) as described in Materials and Methods.