Claim: Sulfiredoxin (which is conserved in all eukaryotes including mammals) belongs to the family of oxireductases which acts on a sulfur group of donors, and is involved in antioxidant metabolism by re-activating peroxiredoxins when they are inhibited by over-oxidation.
Evidence: This enzyme belongs to the family of oxidoreductases, specifically those acting on a sulfur group of donors with other, known, acceptors. This enzyme is involved in antioxidant metabolism by re-activating peroxiredoxins, which are a group of peroxidases, when these enzymes are inhibited by over-oxidation. Initially discovered in yeast, sulfiredoxin is conserved in all eukaryotes, including mammals.