View source for 1b06


==SUPEROXIDE DISMUTASE FROM SULFOLOBUS ACIDOCALDARIUS==
<StructureSection load='1b06' size='340' side='right'caption='[[1b06]], [[Resolution|resolution]] 2.20&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1b06]] is a 6 chain structure with sequence from [https://en.wikipedia.org/wiki/Sulfolobus_acidocaldarius_DSM_639 Sulfolobus acidocaldarius DSM 639]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1B06 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1B06 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]] 2.2&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=FE:FE+(III)+ION'>FE</scene></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=1b06 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1b06 OCA], [https://pdbe.org/1b06 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1b06 RCSB], [https://www.ebi.ac.uk/pdbsum/1b06 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1b06 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/SODF_SULAC SODF_SULAC] Destroys superoxide anion radicals which are normally produced within the cells and which are toxic to biological systems.
== 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/b0/1b06_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=1b06 ConSurf].
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== Publication Abstract from PubMed ==
The extremely thermostable superoxide dismutase from the hyperthermophilic archaeon Sulfolobus acidocaldarius was crystallized and the three-dimensional structure was determined by X-ray diffraction methods. The enzyme crystallized in the monoclinic spacegroup C2 with the cell dimensions a=168.1 A, b=91.3 A, c=85.7 A, beta=91.4 degrees. The diffraction limit of these crystals was 2.2 A. The crystals were very stable in the X-ray beam and measured diffraction data of a single crystal had a completeness of 99.5 % up to a resolution of 2.2 A. The crystal structure of S. acidocaldarius superoxide dismutase was solved by Patterson search methods using a dimer of Thermus thermophilus superoxide dismutase as a search model. The asymmetric unit accommodates three dimers. Two dimers form a tetramer by using only local symmetries; the third dimer forms a tetramer as well, however, by using the crystallographic 2-fold symmetry. The three-dimensional structure of the S. acidocaldarius dismutase has typical features of tetrameric dismutases. Secondary structure elements as well as residues important for the catalytic activity of the enzyme were found to be highly conserved. The model was refined at a resolution of 2.2 A and yielded a crystallographic R-value of 17.4 % (Rfree=22.3 %). A structural comparison of the two extremely stable tetrameric dismutases from S. acidocaldarius and Aquifex pyrophilus with the less stable enzyme from T. thermophilus and Mycoplasma tuberculosis revealed the structural determinants which are probably responsible for the high intrinsic stability of S. acidocaldarius dismutase. The most obvious factor which may give rise to the extraordinary thermal stability of S. acidocaldarius dismutase (melting temperature of about 125 degreesC) is the increase in intersubunit ion pairs and hydrogen bonds and, more importantly, the significant reduction of solvent-accessible hydrophobic surfaces, as well as an increase in the percentage of buried hydrophobic residues.

Refined crystal structure of a superoxide dismutase from the hyperthermophilic archaeon Sulfolobus acidocaldarius at 2.2 A resolution.,Knapp S, Kardinahl S, Hellgren N, Tibbelin G, Schafer G, Ladenstein R J Mol Biol. 1999 Jan 15;285(2):689-702. PMID:9878438<ref>PMID:9878438</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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==See Also==
*[[Superoxide dismutase 3D structures|Superoxide dismutase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Sulfolobus acidocaldarius DSM 639]]
[[Category: Kardinahl S]]
[[Category: Knapp S]]
[[Category: Ladenstein R]]
[[Category: Niklas H]]
[[Category: Schafer G]]
[[Category: Tibbelin G]]