View source for 2obi


==Crystal structure of the Selenocysteine to Cysteine Mutant of human phospholipid hydroperoxide glutathione peroxidase (GPx4)==
<StructureSection load='2obi' size='340' side='right'caption='[[2obi]], [[Resolution|resolution]] 1.55&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2obi]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2OBI OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2OBI FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 1.55&#8491;</td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=2obi FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2obi OCA], [https://pdbe.org/2obi PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2obi RCSB], [https://www.ebi.ac.uk/pdbsum/2obi PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2obi ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/GPX4_HUMAN GPX4_HUMAN] Protects cells against membrane lipid peroxidation and cell death. Required for normal sperm development and male fertility. Could play a major role in protecting mammals from the toxicity of ingested lipid hydroperoxides. Essential for embryonic development. Protects from radiation and oxidative damage (By similarity).
== Evolutionary Conservation ==
[[Image:Consurf_key_small.gif|200px|right]]
Check<jmol>
  <jmolCheckbox>
    <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/ob/2obi_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked>
    <text>to colour the structure by Evolutionary Conservation</text>
  </jmolCheckbox>
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=2obi ConSurf].
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== Publication Abstract from PubMed ==
Phospholipid hydroperoxide glutathione peroxidase (GPx4) is a moonlighting selenoprotein, which has been implicated in anti-oxidative defense, sperm development, and cerebral embryogenesis. Among GPx-isoforms, GPx4 is unique because of its capability to reduce complex lipid hydroperoxides and its tendency toward polymerization, but the structural basis for these properties remained unclear. To address this, we solved the crystal structure of the catalytically active U46C mutant of human GPx4 to 1.55 A resolution. X-ray data indicated a monomeric protein consisting of four alpha-helices and seven beta-strands. GPx4 lacks a surface exposed loop domain, which appears to limit the accessibility of the active site of other GPx-isoforms, and these data may explain the broad substrate specificity of GPx4. The catalytic triad (C46, Q81, and W136) is localized at a flat impression of the protein surface extending into a surface exposed patch of basic amino acids (K48, K135, and R152) that also contains polar T139. Multiple mutations of the catalytic triad indicated its functional importance. Like the wild-type enzyme, the U46C mutant exhibits a strong tendency toward protein polymerization, which was prevented by reductants. Site-directed mutagenesis suggested involvement of the catalytic C46 and surface exposed C10 and C66 in polymer formation. In GPx4 crystals, these residues contact adjacent protein monomers.

Structural basis for catalytic activity and enzyme polymerization of phospholipid hydroperoxide glutathione peroxidase-4 (GPx4).,Scheerer P, Borchert A, Krauss N, Wessner H, Gerth C, Hohne W, Kuhn H Biochemistry. 2007 Aug 7;46(31):9041-9. Epub 2007 Jul 13. PMID:17630701<ref>PMID:17630701</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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==See Also==
*[[Glutathione peroxidase|Glutathione peroxidase]]
== References ==
<references/>
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</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Hoehne W]]
[[Category: Krauss N]]
[[Category: Scheerer P]]