Oxygen Activation and Reduction in Respiration: Involvement of Redox-Active Tyrosine 244
| Autor: | David L. DeWitt, Joseph F. Leykam, Michelle A. Pressler, Gerald T. Babcock, Catherine DeMaso, Denis A. Proshlyakov |
|---|---|
| Rok vydání: | 2000 |
| Předmět: |
Molecular Sequence Data
Iodide chemistry.chemical_element Photochemistry Peptide Mapping Oxygen Electron Transport Complex IV Iodine Radioisotopes Oxygen Consumption medicine Animals Cytochrome c oxidase Moiety Histidine Amino Acid Sequence chemistry.chemical_classification Multidisciplinary biology Proton Pumps Adenosine Peptide Fragments Proton pump Enzyme chemistry Biophysics biology.protein Tyrosine Cattle Dimerization Oxidation-Reduction medicine.drug |
| Zdroj: | Science. 290:1588-1591 |
| ISSN: | 1095-9203 0036-8075 |
| DOI: | 10.1126/science.290.5496.1588 |
| Popis: | Cytochrome oxidase activates and reduces O 2 to water to sustain respiration and uses the energy released to drive proton translocation and adenosine 5′-triphosphate synthesis. A key intermediate in this process, P , lies at the junction of the O 2 -reducing and proton-pumping functions. We used radioactive iodide labeling followed by peptide mapping to gain insight into the structure of P . We show that the cross-linked histidine 240–tyrosine 244 (His 240 -Tyr 244 ) species is redox active in P formation, which establishes its structure as Fe IV =O/Cu B 2+ -H 240 -Y 244 ·. Thus, energy transfer from O 2 to the protein moiety is used as a strategy to avoid toxic intermediates and to control energy utilization in subsequent proton-pumping events. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|