FIGURE 1.
Deglutathionylation of glutathionylated peptide by TGR. The deglutathionylase activities of wild-type TGR (TGRWT) (black box), Grx-less TGR (gray right arrow), and truncated TGR (gray left arrow) were evaluated using a glutathionylated peptide (peptide-S-SG) and NADPH as substrates, following the decrease in absorbance at 340 nm due to NADPH oxidation. The full time courses obtained are shown. The assay was carried out at 100 μm NADPH, 40 μm peptide-S-SG, and 2 nm enzyme. Reaction mixtures without enzyme (white diamond), and with TGRWT and the parental nonglutathionylated peptide (gray diamond) were used as controls. The overall NADPH oxidation corresponds to the consumption of 40 μm peptide-S-SG, which is the limiting substrate.