5xdq
From Proteopedia
Bovine heart cytochrome c oxidase in the fully oxidized state with pH 7.3 at 1.77 angstrom resolution
Structural highlights
FunctionCOX1_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. Publication Abstract from PubMedCytochrome c oxidase (CcO) couples proton pumping to O2 reduction. Its enzymatic activity depends sensitively on pH over a wide range. However, owing to difficulty in crystallizing this protein, X-ray structure analyses of bovine CcO aimed at understanding its reaction mechanism have been conducted using crystals prepared at pH 5.7, which is significantly lower than that in the cell. Here, oxidized CcO at pH 7.3 was crystallized using a fluorinated octyl-maltoside derivative, and the structure was determined at 1.77 A resolution. No structural differences between crystals obtained at the neutral pH and the acidic pH were detected within the molecules. On the other hand, some differences in intermolecular interactions were detected between the two types of crystal. The influence of pH on the molecular surface is likely to contribute to the pH dependency of the aerobic oxidation of ferrocytochrome c. Structure of bovine cytochrome c oxidase crystallized at a neutral pH using a fluorinated detergent.,Luo F, Shinzawa-Itoh K, Hagimoto K, Shimada A, Shimada S, Yamashita E, Yoshikawa S, Tsukihara T Acta Crystallogr F Struct Biol Commun. 2017 Jul 1;73(Pt 7):416-422. doi:, 10.1107/S2053230X17008834. Epub 2017 Jun 20. PMID:28695851[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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