Figure 1.

Thiol oxidase activity of ceCblC. A, time courses of GSSG production (triangles), O₂ consumption (squares) and H₂O₂ production (circles) in reactions containing ceCblC (2.5 μm)-AdoCbl (1.25 μm) and 4 mm GSH. B, thiol oxidase activities of ceCblC (20 μm) in the presence of AdoCbl (10 μm), no cofactor, or EtPhCbl (10 μm), in the presence of 4 mm GSH. C, dependence of the rates of GSSG production (solid circles) and O₂ consumption (empty squares) by ceCblC (2.5 μm)-AdoCbl (1.25 μm) on GSH concentration. The data represent the mean ± S.D. (error bars) of three independent experiments.