1m56

<table><tr><td colspan='2'>[[1m56]] is a 8 chain structure with sequence from [https://en.wikipedia.org/wiki/Rhodobacter_sphaeroides Rhodobacter sphaeroides]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1M56 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1M56 FirstGlance]. <br>

</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=3PE:1,2-DIACYL-SN-GLYCERO-3-PHOSPHOETHANOLAMINE'>3PE</scene>, <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=CU:COPPER+(II)+ION'>CU</scene>, <scene name='pdbligand=HEA:HEME-A'>HEA</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene></td></tr>

<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[https://en.wikipedia.org/wiki/Cytochrome-c_oxidase Cytochrome-c oxidase], with EC number [https://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.9.3.1 1.9.3.1] </span></td></tr>

[[https://www.uniprot.org/uniprot/COX1_RHOSH COX1_RHOSH]] 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. This cytochrome c oxidase shows proton pump activity across the membrane in addition to the electron transfer. [[https://www.uniprot.org/uniprot/COX2_RHOSH COX2_RHOSH]] 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).

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== Publication Abstract from PubMed ==

The structure of cytochrome c oxidase from Rhodobacter sphaeroides has been solved at 2.3/2.8A (anisotropic resolution). This high-resolution structure revealed atomic details of a bacterial terminal oxidase including water molecule positions and a potential oxygen pathway, which has not been reported in other oxidase structures. A comparative study of the wild-type and the EQ(I-286) mutant enzyme revealed structural rearrangements around E(I-286) that could be crucial for proton transfer in this enzyme. In the structure of the mutant enzyme, EQ(I-286), which cannot transfer protons during oxygen reduction, the side-chain of Q(I-286) does not have the hydrogen bond to the carbonyl oxygen of M(I-107) that is seen in the wild-type structure. Furthermore, the Q(I-286) mutant has a different arrangement of water molecules and residues in the vicinity of the Q side-chain. These differences between the structures could reflect conformational changes that take place upon deprotonation of E(I-286) during turnover of the wild-type enzyme, which could be part of the proton-pumping machinery of the enzyme.

The X-ray crystal structures of wild-type and EQ(I-286) mutant cytochrome c oxidases from Rhodobacter sphaeroides.,Svensson-Ek M, Abramson J, Larsson G, Tornroth S, Brzezinski P, Iwata S J Mol Biol. 2002 Aug 9;321(2):329-39. PMID:12144789<ref>PMID:12144789</ref>

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

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== References ==

<references/>

[[Category: Cytochrome-c oxidase]]

[[Category: Abramson, J]]

[[Category: Brezezinski, P]]

[[Category: Iwata, S]]

[[Category: Larsson, G]]

[[Category: Svensson-Ek, M]]

[[Category: Tornroth, S]]

[[Category: Oxidoreductase]]