Disease relevance of VIA L

• The crystal structures of cytochrome c oxidase from both bovine and Paracoccus denitrificans reveal two putative proton input channels that connect the heme-copper center, where dioxygen is reduced, to the internal aqueous phase [1].
• The roles of the two proton input channels in cytochrome c oxidase from Rhodobacter sphaeroides probed by the effects of site-directed mutations on time-resolved electrogenic intraprotein proton transfer [1].
• Cytochrome c1aa3 from Thermus thermophilus has optical and EPR properties similar to bovine cytochrome c oxidase [2].
• Upon fusion of these proteoliposomes with membrane vesicles of Lactococcus lactis, the delta p generated by cytochrome c-oxidase activity was capable to drive uphill transport of leucine [3].
• Cytochrome c oxidase (CcO) is the terminal enzyme of the cell respiratory chain in mitochondria and aerobic bacteria [4].

Psychiatry related information on VIA L

• The incorporation of cytochrome c oxidase into the phospholipid bilayer perturbs the thermodynamic parameters associated with the lipid phase transition in a manner analogous to other integral membrane proteins: it reduces the enthalpy change, lowers the transition temperature, and reduces the cooperative behavior of the phospholipid molecules [5].

High impact information on VIA L

• Cell respiration in mitochondria and some bacteria is catalysed by cytochrome c oxidase, which reduces O2 to water, coupled with translocation of four protons across the mitochondrial or bacterial membrane [6].
• Crystal structures of bovine heart cytochrome c oxidase in the fully oxidized, fully reduced, azide-bound, and carbon monoxide-bound states were determined at 2.30, 2.35, 2.9, and 2.8 angstrom resolution, respectively [7].
• All 13 lipids, including two cardiolipins, one phosphatidylcholine, three phosphatidylethanolamines, four phosphatidylglycerols and three triglycerides, were identified in a crystalline bovine heart cytochrome c oxidase (CcO) preparation [8].
• We show that all cytochrome c oxidase (complex IV) of Saccharomyces cerevisiae is bound to cytochrome c reductase (complex III), which exists in three forms: the free dimer, and two supercomplexes comprising an additional one or two complex IV monomers [9].
• By antibody screening of a rat liver and a rat heart cDNA library in lambda gt11 two clones coding for the liver- and heart-specific subunit VIa of rat cytochrome c oxidase were isolated [10].

Chemical compound and disease context of VIA L

• To enable metal affinity purification of cytochrome c oxidase reconstituted into phospholipid vesicles, a histidine-tag was engineered onto the C-terminal end of the Rhodobacter sphaeroides cytochrome c oxidase subunit II [11].
• NO reacts with purified cytochrome c oxidase forming either a nitrosyl- or a nitrite-inhibited derivative, displaying distinct kinetics and light sensitivity of respiration recovery in the absence of free NO [12].
• Here we present results from EPR experiments on the Rhodobacter sphaeroides cytochrome c oxidase, which show that at high pH (9) approximately 50% of oxidized heme a(3) is hydroxide-ligated, while at low pH (6.5), no hydroxide is bound to heme a(3) [13].
• Multifrequency electron paramagnetic resonance (EPR) spectra of the Cu(II) site in bovine heart cytochrome c oxidase (COX) and nitrous oxide reductase (N2OR) from Pseudomonas stutzeri confirm the existence of Cu-Cu interaction in both enzymes [14].
• The two-subunit bacterial cytochrome c oxidase of Paracoccus denitrificans is proved to be a monomer with a corrected Mr of 76,000 in both nonionic detergents Triton X-100 and dodecyl maltoside [15].

Biological context of VIA L

• A single catalytic site model is proposed to account for the multiphasic kinetics of oxidation of ferrocytochrome c by cytochrome c oxidase (ferrocytochrome c:oxygen oxidoreductase, EC 1.9.3.1) [16].
• In the case of cytochrome c oxidase, this observation means that both the ejected proton and the proton required for the chemistry at the enzyme active site must come from an internal proton pool [17].
• Single catalytic site model for the oxidation of ferrocytochrome c by mitochondrial cytochrome c oxidase [16].
• The mechanism by which electron transfer is coupled to proton pumping in cytochrome c oxidase is a major unsolved problem in molecular bioenergetics [17].
• The mechanisms of nitric oxide (NO) signaling include binding to the iron centers in soluble guanylate cyclase and cytochrome c oxidase and posttranslational modification of proteins by S-nitrosation [18].

Anatomical context of VIA L

• The switching of the subunit VIa isoforms of cytochrome c oxidase has been followed in heart tissue during bovine development both by transcript levels and in terms of the incorporation of L- (liver) and H- (heart) polypeptides into mitochondria [19].
• Cytochrome c oxidase (ferrocytochrome c oxygen oxidoreductase, EC 1.9.3.1) was purified from beef heart mitochondria by affinity chromatography [20].
• In the fused membranes, 55-60% of the cytochrome c oxidase molecules are oriented with the cytochrome c binding site at the outer surface of the membrane [21].
• The integral mitochondrial membrane protein cytochrome c oxidase (ferrocytochrome-c:oxygen oxidoreductase, EC 1.9.3.1) was crystallized from solutions of the protein from bovine heart isolated as described earlier [Yoshikawa, S. & Caughey, W. S. (1982) J. Biol. Chem. 257, 412-420] [22].
• Since sonic irradiation leads to a rearrangement of cytochrome c oxidase in a large fraction of the resulting submitochondrial particles, an immunochemical procedure was developed for isolating particles with a low content of displaced cytochrome c oxidase [23].

Associations of VIA L with chemical compounds

• Diphosphatidylglycerol is required for optimal activity of beef heart cytochrome c oxidase [24].
• Nitric oxide inhibition of respiration involves both competitive (heme) and noncompetitive (copper) binding to cytochrome c oxidase [25].
• Resolution of the electronic transitions of cytochrome c oxidase: evidence for two conformational states of ferrous cytochrome alpha [26].
• Membrane vesicles derived from the strictly fermentative lactic acid bacterium Streptococcus cremoris have been fused with proteoliposomes containing the beef heart mitochondrial cytochrome c oxidase by means of a freeze/thaw-sonication technique [21].
• The procedure is adequate for the purification of all those proteins having in common the property of binding with high affinity to cytochrome c--e.g., cytochrome c oxidase, reductase, and peroxidase, sulfite oxidase, and reaction centers of photosynthetic bacteria [27].

Enzymatic interactions of VIA L

• Attempts to rationalize the kinetics of cytochrome c oxidation catalyzed by solubilized mitochondrial cytochrome c oxidase (ferrocytochrome c:oxygen oxidoreductase, EC 1.9.3.1) have been based on assumptions of productive complex formation (Michaelis-Menten approach) [28].

Regulatory relationships of VIA L

• Binding to cytochrome c oxidase induces a conformational change in the cytochrome c molecule [29].

Other interactions of VIA L

• Cloning and sequencing of the cDNA for a 13th different subunit (IHQ) of beef heart cytochrome c oxidase [30].
• The isolation and sequence determination of the cytoplasmically synthesized polypeptide VIIIb from beef heart cytochrome c oxidase is described [31].
• The isolation and complete sequence analysis of the cytoplasmically synthesized polypeptide VIb from bovine heart cytochrome c oxidase is described [32].
• Direct binding experiments, kinetic studies, and previous work using arylazidocytochrome c derivatives [Bisson, R., Jacobs, B. & Capaldi, R. A. (1980) Biochemistry 10, 4173-4178], indicate that diphosphatidylglycerol is involved in binding of substrate cytochrome c to cytochrome c oxidase [24].
• Noncovalent bonding interactions of nitric oxide (NO) with human serum albumin (HSA), human hemoglobin A, bovine myoglobin, and bovine cytochrome c oxidase (CcO) have been explored [33].

Analytical, diagnostic and therapeutic context of VIA L

• Magnetic circular dichroism and resonance Raman spectra have been obtained for three "oxygenated" derivatives of cytochrome c oxidase (ferrocytochrome c:oxygen oxidoreductase, EC 1.9.3.1) [34].
• An efficient affinity chromatography procedure for the isolation of mitochondrial cytochrome c oxidase and reductase is described [27].
• Second-derivative absorption spectra are reported for a variety of oxidation and ligation states of bovine cytochrome c oxidase (ferrocytochrome-c:oxygen oxidoreductase, EC 1.9.3.1) [26].
• Membrane-bound cytochrome c oxidase catalyzes cell respiration in aerobic organisms and is a primary energy transducer in biology [35].
• Within the past year, the structures of the cytochrome c oxidase from the soil bacterium Paracoccus denitrificans and of the metal centers of the cytochrome c oxidase from bovine heart mitochondria, both determined at 2.8 A resolution by X-ray crystallography, have been reported [36].

References