EC 1.8.98.2 - Sulfiredoxin

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IntEnz Enzyme Nomenclature
EC 1.8.98.2

Names

Accepted name:
sulfiredoxin
Other names:
Srx1
sulphiredoxin
peroxiredoxin-(S-hydroxy-S-oxocysteine) reductase
Systematic name:
peroxiredoxin-(S-hydroxy-S-oxocysteine):thiol oxidoreductase [ATP-hydrolysing; peroxiredoxin-(S-hydroxycysteine)-forming]

Reaction

Comments:

In the course of the reaction of EC 1.11.1.15, peroxiredoxin, its cysteine residue is alternately oxidized to the sulfenic acid, S-hydroxycysteine, and reduced back to cysteine. Occasionally the S-hydroxycysteine residue is further oxidized to the sulfinic acid S-hydroxy-S-oxocysteine, thereby inactivating the enzyme. The reductase provides a mechanism for regenerating the active form of peroxiredoxin, i.e. the peroxiredoxin-(S-hydroxycysteine) form. Apparently the reductase first catalyses the phosphorylation of the -S(O)-OH group by ATP to give -S(O)-O-P, which is attached to the peroxiredoxin by a cysteine residue, forming an -S(O)-S- link between the two enzymes. Attack by a thiol splits this bond, leaving the peroxiredoxin as the sulfenic acid and the reductase as the thiol.

Links to other databases

Enzymes and pathways: NC-IUBMB , BRENDA , ExplorEnz , ENZYME@ExPASy , KEGG , MetaCyc , UniPathway
Structural data: CSA , EC2PDB
Gene Ontology: GO:0032542
UniProtKB/Swiss-Prot:

References

  1. Biteau, B., Labarre, J. and Toledano, M.B.
    ATP-dependent reduction of cysteine—sulphinic acid by S. cerevisiae sulphiredoxin.
    Nature 425: 980-984 (2003). [PMID: 14586471]
  2. Chang, T.-S., Jeong, W., Woo, H.A., Lee, S.M., Park, S. and Rhee, S.G.
    Characterization of mammalian sulfiredoxin and its reactivation of hyperoxidized peroxiredoxin through reduction of cysteine sulfinic acid in the active site to cysteine.
    J. Biol. Chem. 279: 50994-51001 (2004). [PMID: 15448164]
  3. Woo, H.A., Jeong, W., Chang, T.-S., Park, K.J., Park, S.J., Yang, J.S. and Rhee, S.G.
    Reduction of cysteine sulfinic acid by sulfiredoxin is specific to 2-Cys peroxiredoxins.
    J. Biol. Chem. 280: 3125-3128 (2005). [PMID: 15590625]

[1.8.98.2 created 2005]