FIG. 6.

Peroxiredoxin involvement in redox signaling. In scenario (A), the peroxiredoxins are responsible for removing endogenous levels of hydrogen peroxide, but at higher fluxes the peroxiredoxins are inactivated by hyperoxidation, enabling the oxidation of less reactive target proteins. In (B), the peroxiredoxins interact with target proteins, facilitating their oxidation by thiol exchange reactions. For clarity, only one peroxiredoxin subunit and its peroxidatic cysteine are shown in this diagram.