2cv4
Crystal Structure of an Archaeal Peroxiredoxin from the Aerobic Hyperthermophilic Crenarchaeon Aeropyrum pernix K1
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OverviewOverview
Peroxiredoxins (Prxs) are thiol-dependent peroxidases that catalyze the, detoxification of various peroxide substrates such as H2O2, peroxinitrite, and hydroperoxides, and control some signal transduction in eukaryotic, cells. Prxs are found in all cellular organisms and represent an enormous, superfamily. Recent genome sequencing projects and biochemical studies, have identified a novel subfamily, the archaeal Prxs. Their primary, sequences are similar to those of the 1-Cys Prxs, which use only one, cysteine residue in catalysis, while their catalytic properties resemble, those of the typical 2-Cys Prxs, which utilize two cysteine residues from, adjacent monomers within a dimer in catalysis. We present here the X-ray, crystal structure of an archaeal Prx from the aerobic hyperthermophilic, crenarchaeon, Aeropyrum pernix K1, determined at 2.3 A resolution (Rwork, of 17.8% and Rfree of 23.0%). The overall subunit arrangement of the, A.pernix archaeal Prx is a toroid-shaped pentamer of homodimers, or an, (alpha2)5 decamer, as observed in the previously reported crystal, structures of decameric Prxs. The basic folding topology and the, peroxidatic active site structure are essentially the same as those of the, 1-Cys Prx, hORF6, except that the C-terminal extension of the A.pernix, archaeal Prx forms a unique helix with its flanking loops. The thiol group, of the peroxidatic cysteine C50 is overoxidized to sulfonic acid. Notably, the resolving cysteine C213 forms the intra-monomer disulfide bond with, the third cysteine, C207, which should be a unique structural, characteristic in the many archaeal Prxs that retain two conserved, cysteine residues in the C-terminal region. The conformational flexibility, near the intra-monomer disulfide linkage might be necessary for the, dramatic structural rearrangements that occur in the catalytic cycle.
About this StructureAbout this Structure
2CV4 is a Single protein structure of sequence from Aeropyrum pernix with MES and IPA as ligands. This structure superseeds the now removed PDB entry 1VGS. Full crystallographic information is available from OCA.
ReferenceReference
Crystal structure of an archaeal peroxiredoxin from the aerobic hyperthermophilic crenarchaeon Aeropyrum pernix K1., Mizohata E, Sakai H, Fusatomi E, Terada T, Murayama K, Shirouzu M, Yokoyama S, J Mol Biol. 2005 Nov 25;354(2):317-29. Epub 2005 Sep 22. PMID:16214169
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