The site of the redox-linked proton pump in eukaryotic cytochrome c oxidases.
The electronic spectra of fully oxidized derivatives of some cytochrome c oxidase preparations are distinctly pH dependent. In general, the observed spectral shifts are greater in the case of pulsed derivatives compared to resting preparations and also, greater for preparations of the enzyme from shark skeletal muscle compared to beef heart. The low temperature near-infrared magnetic circular dichroism spectrum of the fully oxidized shark enzyme is not pH dependent in the experimental range, indicating the sensitivity of the visible region electronic spectrum to variation in pH to be due principally to changes at the heme a3-CuB chromophore. The results are discussed in relation to proposed mechanisms of proton translocation in cytochrome c oxidase.
Duke Scholars
Published In
DOI
EISSN
ISSN
Publication Date
Volume
Issue
Start / End Page
Related Subject Headings
- Spectrophotometry
- Sharks
- Proton Pumps
- Protein Conformation
- Oxidation-Reduction
- Muscle, Skeletal
- Models, Structural
- Electron Transport Complex IV
- Electron Transport
- Electron Spin Resonance Spectroscopy
Citation
Published In
DOI
EISSN
ISSN
Publication Date
Volume
Issue
Start / End Page
Related Subject Headings
- Spectrophotometry
- Sharks
- Proton Pumps
- Protein Conformation
- Oxidation-Reduction
- Muscle, Skeletal
- Models, Structural
- Electron Transport Complex IV
- Electron Transport
- Electron Spin Resonance Spectroscopy