Suppressing hydrogen peroxide generation to achieve oxygen-insensitivity of a [NiFe] hydrogenase in redox active films
| Autor: | Wolfgang Lubitz, Nicolas Plumeré, Erik Freier, Huaiguang Li, Darren Buesen, Ute Münchberg, Alaa A. Oughli |
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| Rok vydání: | 2019 |
| Předmět: |
Hydrogenase
Science Iodide General Physics and Astronomy chemistry.chemical_element 02 engineering and technology Oxidative phosphorylation 010402 general chemistry Photochemistry 01 natural sciences Oxygen Redox General Biochemistry Genetics and Molecular Biology Article Catalysis chemistry.chemical_compound Bacterial Proteins Desulfovibrio vulgaris Hydrogen peroxide lcsh:Science chemistry.chemical_classification Multidisciplinary Energy Catalytic mechanisms General Chemistry Hydrogen Peroxide 021001 nanoscience & nanotechnology Decomposition 0104 chemical sciences Kinetics chemistry lcsh:Q 0210 nano-technology Electrocatalysis Oxidation-Reduction |
| Zdroj: | Nature Communications Nature Communications, Vol 11, Iss 1, Pp 1-7 (2020) |
| ISSN: | 2041-1723 |
| Popis: | Redox-active films were proposed as protective matrices for preventing oxidative deactivation of oxygen-sensitive catalysts such as hydrogenases for their use in fuel cells. However, the theoretical models predict quasi-infinite protection from oxygen and the aerobic half-life for hydrogenase-catalyzed hydrogen oxidation within redox films lasts only about a day. Here, we employ operando confocal microscopy to elucidate the deactivation processes. The hydrogen peroxide generated from incomplete reduction of oxygen induces the decomposition of the redox matrix rather than deactivation of the biocatalyst. We show that efficient dismutation of hydrogen peroxide by iodide extends the aerobic half-life of the catalytic film containing an oxygen-sensitive [NiFe] hydrogenase to over one week, approaching the experimental anaerobic half-life. Altogether, our data support the theory that redox films make the hydrogenases immune against the direct deactivation by oxygen and highlight the importance of suppressing hydrogen peroxide production in order to reach complete protection from oxidative stress. Oxidative degradation impedes practical applications of highly active but fragile catalysts. Here the authors show that combining a protection matrix for O2 reduction and hydrogen peroxide decomposition stabilizes highly O2-sensitive hydrogenase in the harsh oxidative conditions of operating fuel cells. |
| Databáze: | OpenAIRE |
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