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Water oxidation by Ferritin: A semi-natural electrode.

ABSTRACT: Ferritin is a protein (ca. 12?nm) with a central pocket of 6?nm diameter, and hydrated iron oxide stored in this central cavity of this protein. The protein shell has a complicated structure with 24 subunits. Transmission electron microscopy images of ferritin showed nanosized iron oxides (ca. 4-6?nm) in the protein structure. In high-resolution transmission electron microscopy images of the iron core, d-spacings of 2.5-2.6?Å were observed, which is corresponded to d-spacings of ferrihydrite crystal structure. Our experiments showed that at pH 11, the modified electrode by this biomolecule is active for water oxidation (turnover frequency: 0.001?s^-1 at 1.7?V). Using affected by bacteria, we showed that Fe ions in the structure of ferritin are critical for water oxidation.

SUBMITTER: Abdi Z

PROVIDER: S-EPMC6687787 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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Water oxidation by Ferritin: A semi-natural electrode.

Abdi Zahra Z Bagheri Robabeh R Song Zhenlun Z Najafpour Mohammad Mahdi MM

Scientific reports 20190808 1

Ferritin is a protein (ca. 12 nm) with a central pocket of 6 nm diameter, and hydrated iron oxide stored in this central cavity of this protein. The protein shell has a complicated structure with 24 subunits. Transmission electron microscopy images of ferritin showed nanosized iron oxides (ca. 4-6 nm) in the protein structure. In high-resolution transmission electron microscopy images of the iron core, d-spacings of 2.5-2.6 Å were observed, which is corresponded to d-spacings of ferrihydrite cry ...[more]

PMID: 31395911

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