View source for 3qjs

==The structure of and photolytic induced changes of carbon monoxide binding to the cytochrome ba3-oxidase from Thermus thermophilus==
<StructureSection load='3qjs' size='340' side='right' caption='[[3qjs]], [[Resolution|resolution]] 2.80&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[3qjs]] is a 3 chain structure with sequence from [http://en.wikipedia.org/wiki/Thermus_thermophilus Thermus thermophilus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3QJS OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3QJS FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=CMO:CARBON+MONOXIDE'>CMO</scene>, <scene name='pdbligand=CU1:COPPER+(I)+ION'>CU1</scene>, <scene name='pdbligand=CUA:DINUCLEAR+COPPER+ION'>CUA</scene>, <scene name='pdbligand=HAS:HEME-AS'>HAS</scene>, <scene name='pdbligand=HEM:PROTOPORPHYRIN+IX+CONTAINING+FE'>HEM</scene></td></tr>
<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[2qpd|2qpd]], [[2qpe|2qpe]], [[3eh3|3eh3]], [[3eh4|3eh4]], [[3eh5|3eh5]], [[3qjq|3qjq]], [[3qjr|3qjr]], [[3qjt|3qjt]], [[3qju|3qju]], [[3qjv|3qjv]]</td></tr>
<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">cbaA, TTHA1135 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=274 Thermus thermophilus]), cbaB, ctaC, TTHA1134 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=274 Thermus thermophilus]), cbaD, TTHA1133 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=274 Thermus thermophilus])</td></tr>
<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Cytochrome-c_oxidase Cytochrome-c oxidase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.9.3.1 1.9.3.1] </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=3qjs FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3qjs OCA], [http://www.rcsb.org/pdb/explore.do?structureId=3qjs RCSB], [http://www.ebi.ac.uk/pdbsum/3qjs PDBsum]</span></td></tr>
</table>
== Function ==
[[http://www.uniprot.org/uniprot/COX2_THET8 COX2_THET8]] Subunits I and II form the functional core of the enzyme complex. Electrons originating in cytochrome c are transferred via heme a and Cu(A) to the binuclear center formed by heme a3 and Cu(B). 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The purpose of the work was to provide a crystallographic demonstration of the venerable idea that CO photolyzed from ferrous heme-a(3) moves to the nearby cuprous ion in the cytochrome c oxidases. Crystal structures of CO-bound cytochrome ba(3)-oxidase from Thermus thermophilus, determined at ~2.8-3.2A resolution, reveal a Fe-C distance of ~2.0A, a Cu-O distance of 2.4A and a Fe-C-O angle of ~126 degrees . Upon photodissociation at 100K, X-ray structures indicate loss of Fe(a3)-CO and appearance of Cu(B)-CO having a Cu-C distance of ~1.9A and an O-Fe distance of ~2.3A. Absolute FTIR spectra recorded from single crystals of reduced ba(3)-CO that had not been exposed to X-ray radiation, showed several peaks around 1975cm(-1); after photolysis at 100K, the absolute FTIR spectra also showed a significant peak at 2050cm(-1). Analysis of the 'light' minus 'dark' difference spectra showed four very sharp CO stretching bands at 1970cm(-1), 1977cm(-1), 1981cm(-1), and 1985cm(-1), previously assigned to the Fe(a3)-CO complex, and a significantly broader CO stretching band centered at ~2050cm(-1), previously assigned to the CO stretching frequency of Cu(B) bound CO. As expected for light propagating along the tetragonal axis of the P4(3)2(1)2 space group, the single crystal spectra exhibit negligible dichroism. Absolute FTIR spectrometry of a CO-laden ba(3) crystal, exposed to an amount of X-ray radiation required to obtain structural data sets before FTIR characterization, showed a significant signal due to photogenerated CO(2) at 2337cm(-1) and one from traces of CO at 2133cm(-1); while bands associated with CO bound to either Fe(a3) or to Cu(B) in "light" minus "dark" FTIR difference spectra shifted and broadened in response to X-ray exposure. In spite of considerable radiation damage to the crystals, both X-ray analysis at 2.8 and 3.2A and FTIR spectra support the long-held position that photolysis of Fe(a3)-CO in cytochrome c oxidases leads to significant trapping of the CO on the Cu(B) atom; Fe(a3) and Cu(B) ligation, at the resolutions reported here, are otherwise unaltered. This article is part of a Special Issue entitled: Respiratory Oxidases.

Structural changes that occur upon photolysis of the Fe(II)(a3)-CO complex in the cytochrome ba(3)-oxidase of Thermus thermophilus: A combined X-ray crystallographic and infrared spectral study demonstrates CO binding to Cu(B).,Liu B, Zhang Y, Sage JT, Soltis SM, Doukov T, Chen Y, Stout CD, Fee JA Biochim Biophys Acta. 2011 Dec 27. PMID:22226917<ref>PMID:22226917</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>

==See Also==
*[[Cytochrome c oxidase|Cytochrome c oxidase]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Cytochrome-c oxidase]]
[[Category: Thermus thermophilus]]
[[Category: Chen, Y]]
[[Category: Doukov, T]]
[[Category: Fee, J A]]
[[Category: Liu, B]]
[[Category: Sage, J T]]
[[Category: Stout, C D]]
[[Category: Zhang, Y]]
[[Category: Carbon monoxide]]
[[Category: Co photodissociation]]
[[Category: Cytochrome ba3 oxidase]]
[[Category: Oxidoreductase]]