View source for 3ljf


==The X-ray structure of iron superoxide dismutase from Pseudoalteromonas haloplanktis (crystal form II)==
<StructureSection load='3ljf' size='340' side='right' caption='[[3ljf]], [[Resolution|resolution]] 2.10&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[3ljf]] is a 4 chain structure with sequence from [http://en.wikipedia.org/wiki/Pseht Pseht]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3LJF OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3LJF FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=FE:FE+(III)+ION'>FE</scene>, <scene name='pdbligand=TRE:TREHALOSE'>TRE</scene></td></tr>
<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[3lio|3lio]], [[3lj9|3lj9]]</td></tr>
<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">sodB, PSHAa1215 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=326442 PSEHT])</td></tr>
<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Superoxide_dismutase Superoxide dismutase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.15.1.1 1.15.1.1] </span></td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3ljf FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3ljf OCA], [http://pdbe.org/3ljf PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=3ljf RCSB], [http://www.ebi.ac.uk/pdbsum/3ljf PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=3ljf ProSAT]</span></td></tr>
</table>
== Function ==
[[http://www.uniprot.org/uniprot/SODF_PSEHT SODF_PSEHT]] Destroys superoxide anion radicals which are normally produced within the cells and which are toxic to biological systems.<ref>PMID:16713057</ref>  
== 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/lj/3ljf_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=3ljf ConSurf].
<div style="clear:both"></div>
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== Publication Abstract from PubMed ==
Superoxide dismutases (SODs) are metalloenzymes catalysing the dismutation of superoxide anion radicals into molecular oxygen and hydrogen peroxide. Here, we present the crystal structure of a cold-adapted Fe-SOD from the Antarctic eubacterium Pseudoalteromonas haloplanktis (PhSOD), and that of its complex with sodium azide. The structures were compared with those of the corresponding homologues having a high sequence identity with PhSOD, such as the mesophilic SOD from Escherichia coli (EcSOD) or Pseudomonas ovalis, and the psychrophilic SOD from Aliivibrio salmonicida (AsSOD). These enzymes shared a large structural similarity, such as a conserved tertiary structure and arrangement of the two monomers, an almost identical total number of inter- and intramolecular hydrogen bonds and salt bridges. However, the two cold-adapted SODs showed an increased flexibility of the active site residues with respect to their mesophilic homologues. Structural information was combined with a characterisation of the chemical and thermal stability performed by CD and fluorescence measurements. Despite of its psychrophilic origin, the denaturation temperature of PhSOD was comparable with that of the mesophilic EcSOD, whereas AsSOD showed a lower denaturation temperature. On the contrary, the values of the denaturant concentration at the transition midpoint were in line with the psychrophilic/mesophilic origin of the proteins. These data provide additional support to the hypothesis that cold-adapted enzymes achieve efficient catalysis at low temperature, by increasing the flexibility of their active site; moreover, our results underline how fine structural modifications can alter enzyme flexibility and/or stability without compromising the overall structure of typical rigid enzymes, such as SODs.

Structure and flexibility in cold-adapted iron superoxide dismutases: The case of the enzyme isolated from Pseudoalteromonas haloplanktis.,Merlino A, Krauss IR, Castellano I, Vendittis ED, Rossi B, Conte M, Vergara A, Sica F J Struct Biol. 2010 Aug 21. PMID:20732427<ref>PMID:20732427</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 3ljf" style="background-color:#fffaf0;"></div>

==See Also==
*[[Superoxide Dismutase|Superoxide Dismutase]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Pseht]]
[[Category: Superoxide dismutase]]
[[Category: Conte, M]]
[[Category: Krauss, I Russo]]
[[Category: Merlino, A]]
[[Category: Rossi, B]]
[[Category: Sica, F]]
[[Category: Vergara, A]]
[[Category: Cold adaptation]]
[[Category: Flexibility]]
[[Category: Metal-binding]]
[[Category: Oxidoreductase]]
[[Category: Psychrophilic protein]]
[[Category: Thermal stability]]