1m57
From Proteopedia
Structure of cytochrome c oxidase from Rhodobacter sphaeroides (EQ(I-286) mutant))
Structural highlights
Function[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. [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). Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedThe 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[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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