View source for 2mhr


==STRUCTURE OF MYOHEMERYTHRIN IN THE AZIDOMET STATE AT 1.7(SLASH)1.3 ANGSTROMS RESOLUTION==
<StructureSection load='2mhr' size='340' side='right' caption='[[2mhr]], [[Resolution|resolution]] 1.30&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2mhr]] is a 1 chain structure. This structure supersedes the now removed PDB entry [http://oca.weizmann.ac.il/oca-bin/send-pdb?obs=1&id=1mhr 1mhr]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2MHR OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2MHR FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=AZI:AZIDE+ION'>AZI</scene>, <scene name='pdbligand=FEO:MU-OXO-DIIRON'>FEO</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene></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=2mhr FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2mhr OCA], [http://pdbe.org/2mhr PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=2mhr RCSB], [http://www.ebi.ac.uk/pdbsum/2mhr PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=2mhr ProSAT]</span></td></tr>
</table>
== Function ==
[[http://www.uniprot.org/uniprot/HEMTM_THEHE HEMTM_THEHE]] Myohemerythrin is an oxygen-binding protein found in the retractor muscles of certain worms. The oxygen-binding site contains two iron atoms. 
== 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/mh/2mhr_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=2mhr ConSurf].
<div style="clear:both"></div>
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== Publication Abstract from PubMed ==
The molecular model of myohemerythrin, an oxygen-carrying protein from sipunculan worms, has been refined by stereochemically restrained least-squares minimization at 1.7/1.3 A resolution to a conventional R-value of 0.158. The estimated positional standard deviation is better than 0.15 A for most of the 979 protein atoms. The average isotropic displacement parameter, B, for the protein atoms is 23.1 A2. This high average B parameter appears to be due to the overall motion of the molecule, which correlates with the observed anisotropic diffraction. The side-chains of seven residues were modeled in two conformations, i.e. the side-chains were discretely disordered, and B parameters for several lysine and glutamate side-chains indicate that they are poorly localized. Of the residues in myohemerythrin, 66% are helical, with 62% occurring in four long alpha-helices with mean values for the backbone torsion angles of phi = -65 degrees, psi = -42 degrees, and for the hydrogen bonds distances of N ... O, 3.0 A and H ... O, 2.1 A, and angles of N ... O = C, 153 degrees, N-H ... O, 157 degrees, and H ... O = C, 147 degrees. For two-thirds of the alpha-helical residues, the torsional rotation of the C alpha-C beta bond, chi 1, is approximately -60 degrees, and for one-third chi 1 is approximately 180 degrees. Although most turns in myohemerythrin are well-categorized by previous classification, two do not fit in established patterns. Also included in the refined model are three sulfate ions, all partially occupied, and 157 water molecules, 40% of which are modeled fully occupied. Only one water molecule is internal to the protein, the remainder occur on the surface and are observed principally between symmetry-related molecules contributing, along with van der Waals' contacts, most of the interactions between molecules. There are eight intermolecular protein-protein hydrogen bonds, of which only four are between well-located atoms.

Structure of myohemerythrin in the azidomet state at 1.7/1.3 A resolution.,Sheriff S, Hendrickson WA, Smith JL J Mol Biol. 1987 Sep 20;197(2):273-96. PMID:3681996<ref>PMID:3681996</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 2mhr" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Hendrickson, W A]]
[[Category: Sheriff, S]]
[[Category: Oxygen binding]]