View source for 3abm


==Bovine heart cytochrome c oxidase at the fully oxidized state (200-s X-ray exposure dataset)==
<StructureSection load='3abm' size='340' side='right'caption='[[3abm]], [[Resolution|resolution]] 1.95&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[3abm]] is a 20 chain structure with sequence from [https://en.wikipedia.org/wiki/Bos_taurus Bos taurus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3ABM OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3ABM 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]] 1.95&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CDL:CARDIOLIPIN'>CDL</scene>, <scene name='pdbligand=CHD:CHOLIC+ACID'>CHD</scene>, <scene name='pdbligand=CU:COPPER+(II)+ION'>CU</scene>, <scene name='pdbligand=CUA:DINUCLEAR+COPPER+ION'>CUA</scene>, <scene name='pdbligand=DMU:DECYL-BETA-D-MALTOPYRANOSIDE'>DMU</scene>, <scene name='pdbligand=FME:N-FORMYLMETHIONINE'>FME</scene>, <scene name='pdbligand=HEA:HEME-A'>HEA</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=NA:SODIUM+ION'>NA</scene>, <scene name='pdbligand=PEK:(1S)-2-{[(2-AMINOETHOXY)(HYDROXY)PHOSPHORYL]OXY}-1-[(STEAROYLOXY)METHYL]ETHYL+(5E,8E,11E,14E)-ICOSA-5,8,11,14-TETRAENOATE'>PEK</scene>, <scene name='pdbligand=PER:PEROXIDE+ION'>PER</scene>, <scene name='pdbligand=PGV:(1R)-2-{[{[(2S)-2,3-DIHYDROXYPROPYL]OXY}(HYDROXY)PHOSPHORYL]OXY}-1-[(PALMITOYLOXY)METHYL]ETHYL+(11E)-OCTADEC-11-ENOATE'>PGV</scene>, <scene name='pdbligand=PSC:(7R,17E,20E)-4-HYDROXY-N,N,N-TRIMETHYL-9-OXO-7-[(PALMITOYLOXY)METHYL]-3,5,8-TRIOXA-4-PHOSPHAHEXACOSA-17,20-DIEN-1-AMINIUM+4-OXIDE'>PSC</scene>, <scene name='pdbligand=SAC:N-ACETYL-SERINE'>SAC</scene>, <scene name='pdbligand=TGL:TRISTEAROYLGLYCEROL'>TGL</scene>, <scene name='pdbligand=TPO:PHOSPHOTHREONINE'>TPO</scene>, <scene name='pdbligand=UNX:UNKNOWN+ATOM+OR+ION'>UNX</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</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=3abm FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3abm OCA], [https://pdbe.org/3abm PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3abm RCSB], [https://www.ebi.ac.uk/pdbsum/3abm PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3abm ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/COX1_BOVIN COX1_BOVIN] Cytochrome c oxidase is the component of the respiratory chain that catalyzes the reduction of oxygen to water. Subunits 1-3 form the functional core of the enzyme complex. CO I is the catalytic subunit of the enzyme. Electrons originating in cytochrome c are transferred via the copper A center of subunit 2 and heme A of subunit 1 to the bimetallic center formed by heme A3 and copper B.
== 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/ab/3abm_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=3abm ConSurf].
<div style="clear:both"></div>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The fully oxidized form of cytochrome c oxidase, immediately after complete oxidation of the fully reduced form, pumps protons upon each of the initial 2 single-electron reduction steps, whereas protons are not pumped during single-electron reduction of the fully oxidized "as-isolated" form (the fully oxidized form without any reduction/oxidation treatment) [Bloch D, et al. (2004) The catalytic cycle of cytochrome c oxidase is not the sum of its two halves. Proc Natl Acad Sci USA 101:529-533]. For identification of structural differences causing the remarkable functional difference between these 2 distinct fully oxidized forms, the X-ray structure of the fully oxidized as-isolated bovine heart cytochrome c oxidase was determined at 1.95-A resolution by limiting the X-ray dose for each shot and by using many (approximately 400) single crystals. This minimizes the effects of hydrated electrons induced by the X-ray irradiation. The X-ray structure showed a peroxide group bridging the 2 metal sites in the O(2) reduction site (Fe(3+)-O(-)-O(-)-Cu(2+)), in contrast to a ferric hydroxide (Fe(3+)-OH(-)) in the fully oxidized form immediately after complete oxidation from the fully reduced form, as has been revealed by resonance Raman analyses. The peroxide-bridged structure is consistent with the reductive titration results showing that 6 electron equivalents are required for complete reduction of the fully oxidized as-isolated form. The structural difference between the 2 fully oxidized forms suggests that the bound peroxide in the O(2) reduction site suppresses the proton pumping function.

A peroxide bridge between Fe and Cu ions in the O2 reduction site of fully oxidized cytochrome c oxidase could suppress the proton pump.,Aoyama H, Muramoto K, Shinzawa-Itoh K, Hirata K, Yamashita E, Tsukihara T, Ogura T, Yoshikawa S Proc Natl Acad Sci U S A. 2009 Feb 17;106(7):2165-9. Epub 2009 Jan 21. PMID:19164527<ref>PMID:19164527</ref>

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

==See Also==
*[[Cytochrome c oxidase 3D structures|Cytochrome c oxidase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Bos taurus]]
[[Category: Large Structures]]
[[Category: Aoyama H]]
[[Category: Muramoto K]]
[[Category: Ogura T]]
[[Category: Shinzawa-Itoh K]]
[[Category: Tsukihara T]]
[[Category: Yamashita E]]
[[Category: Yoshikawa S]]