1qq2
CRYSTAL STRUCTURE OF A MAMMALIAN 2-CYS PEROXIREDOXIN, HBP23.
Structural highlights
FunctionPRDX1_RAT Involved in redox regulation of the cell. Reduces peroxides with reducing equivalents provided through the thioredoxin system but not from glutaredoxin. May play an important role in eliminating peroxides generated during metabolism. Might participate in the signaling cascades of growth factors and tumor necrosis factor-alpha by regulating the intracellular concentrations of H(2)O(2). Reduces an intramolecular disulfide bond in GDPD5 that gates the ability to GDPD5 to drive postmitotic motor neuron differentiation (By similarity). Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedHeme-binding protein 23 kDa (HBP23), a rat isoform of human proliferation-associated gene product (PAG), is a member of the peroxiredoxin family of peroxidases, having two conserved cysteine residues. Recent biochemical studies have shown that HBP23/PAG is an oxidative stress-induced and proliferation-coupled multifunctional protein that exhibits specific bindings to c-Abl protein tyrosine kinase and heme, as well as a peroxidase activity. A 2.6-A resolution crystal structure of rat HBP23 in oxidized form revealed an unusual dimer structure in which the active residue Cys-52 forms a disulfide bond with conserved Cys-173 from another subunit by C-terminal tail swapping. The active site is largely hydrophobic with partially exposed Cys-173, suggesting a reduction mechanism of oxidized HBP23 by thioredoxin. Thus, the unusual cysteine disulfide bond is involved in peroxidation catalysis by using thioredoxin as the source of reducing equivalents. The structure also provides a clue to possible interaction surfaces for c-Abl and heme. Several significant structural differences have been found from a 1-Cys peroxiredoxin, ORF6, which lacks the C-terminal conserved cysteine corresponding to Cys-173 of HBP23. Crystal structure of a multifunctional 2-Cys peroxiredoxin heme-binding protein 23 kDa/proliferation-associated gene product.,Hirotsu S, Abe Y, Okada K, Nagahara N, Hori H, Nishino T, Hakoshima T Proc Natl Acad Sci U S A. 1999 Oct 26;96(22):12333-8. PMID:10535922[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences | ||||||||||||||||||||
