CATH Classification

Domain Context

CATH Clusters

Superfamily Conserved hypothetical protein from pyrococcus furiosus pfu- 392566-001, ParB domain
Functional Family Sulfiredoxin

Enzyme Information

1.8.98.2
Sulfiredoxin.
based on mapping to UniProt Q9BYN0
Peroxiredoxin-(S-hydroxy-S-oxocysteine) + ATP + 2 R-SH = peroxiredoxin- (S-hydroxycysteine) + ADP + phosphate + R-S-S-R.
-!- In the course of the reaction of EC 1.11.1.15, 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 catalyzes 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.

UniProtKB Entries (1)

Q9BYN0
SRXN1_HUMAN
Homo sapiens
Sulfiredoxin-1

PDB Structure

PDB 3HY2
External Links
Method X-RAY DIFFRACTION
Organism
Primary Citation
Protein Engineering of the Quaternary Sulfiredoxin-Peroxiredoxin Enzyme-Substrate Complex Reveals the Molecular Basis for Cysteine Sulfinic Acid Phosphorylation
Jonsson, T.J., Johnson, L.C., Lowther, W.T.
J.Biol.Chem.