Cytochrome c interaction with hematite (α-Fe2O3) surfaces
Autor: | Nidhi Khare, Carrick M. Eggleston, David M. Lovelace |
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Rok vydání: | 2006 |
Předmět: |
Radiation
Aqueous solution biology Cytochrome Chemistry Cytochrome c Inorganic chemistry Oxide food and beverages Hematite Condensed Matter Physics Redox Atomic and Molecular Physics and Optics Electronic Optical and Magnetic Materials chemistry.chemical_compound visual_art biology.protein visual_art.visual_art_medium medicine Ferric Physical and Theoretical Chemistry Cyclic voltammetry Spectroscopy medicine.drug |
Zdroj: | Journal of Electron Spectroscopy and Related Phenomena. 150:220-227 |
ISSN: | 0368-2048 |
DOI: | 10.1016/j.elspec.2005.06.006 |
Popis: | The interaction of metalloproteins such as cytochromes with oxides is of interest for a number of reasons, including molecular catalysis of environmentally important mineral-solution electron transfer reactions (e.g., dehalogenations) and photovoltaic applications. Iron reduction by bacteria, thought to be cytochrome mediated, is of interest for geochemical and environmental remediation reasons. As a baseline for understanding cytochrome interaction with ferric oxide surfaces, we report on the interaction of mitochondrial cytochrome c (Mcc), a well-studied protein, with hematite (α-Fe 2 O 3 ) surfaces. Mcc sorbs strongly to hematite from aqueous solution in a narrow pH range corresponding to opposite charge on Mcc and hematite (between pH 8.5 and 10, Mcc is positively charged and hematite surfaces are negatively charged). Cyclic voltammetry of Mcc using hematite electrodes gives redox potentials characteristic of Mcc in a native conformational state, with no evidence for unfolding on the hematite surface. Atomic force microscopy imaging is consistent with a loosely attached adsorbate that is easily deformed by the AFM tip. In phosphate-containing solution, Mcc adhers to the surface more strongly. These results establish hematite as a viable material for electrochemical and spectroscopic characterization of cytochrome–mineral interaction. |
Databáze: | OpenAIRE |
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