Reduction Kinetic of Water Soluble Metal Salts by Geobacter sulfurreducens: Fe2+/Hemes Stabilize and Regulate Electron Flux Rates
Geobacter sulfurreducens is a widely applied microorganism for the reduction of toxic metal salts, as an electron source for bioelectrochemical devices, and as a reagent for the synthesis of nanoparticles. In order to understand the influence of metal salts, and of electron transporting, multiheme c...
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2022-06-01
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| Series: | Frontiers in Microbiology |
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| Online Access: | https://www.frontiersin.org/articles/10.3389/fmicb.2022.909109/full |
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| author | Maksym Karamash Michael Stumpe Jörn Dengjel Carlos A. Salgueiro Carlos A. Salgueiro Bernd Giese Katharina M. Fromm |
| author_facet | Maksym Karamash Michael Stumpe Jörn Dengjel Carlos A. Salgueiro Carlos A. Salgueiro Bernd Giese Katharina M. Fromm |
| author_sort | Maksym Karamash |
| collection | DOAJ |
| description | Geobacter sulfurreducens is a widely applied microorganism for the reduction of toxic metal salts, as an electron source for bioelectrochemical devices, and as a reagent for the synthesis of nanoparticles. In order to understand the influence of metal salts, and of electron transporting, multiheme c-cytochromes on the electron flux during respiration of G. sulfurreducens, the reduction kinetic of Fe3+, Co3+, V5+, Cr6+, and Mn7+ containing complexes were measured. Starting from the resting phase, each G. sulfurreducens cell produced an electron flux of 3.7 × 105 electrons per second during the respiration process. Reduction rates were within ± 30% the same for the 6 different metal salts, and reaction kinetics were of zero order. Decrease of c-cytochrome concentrations by downregulation and mutation demonstrated that c-cytochromes stabilized respiration rates by variation of their redox states. Increasing Fe2+/heme levels increased electron flux rates, and induced respiration flexibility. The kinetic effects parallel electrochemical results of G. sulfurreducens biofilms on electrodes, and might help to optimize bioelectrochemical devices. |
| first_indexed | 2024-12-12T03:54:15Z |
| format | Article |
| id | doaj.art-bd8a6a88362c4625ba37d6c8bef17dce |
| institution | Directory Open Access Journal |
| issn | 1664-302X |
| language | English |
| last_indexed | 2024-12-12T03:54:15Z |
| publishDate | 2022-06-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Microbiology |
| spelling | doaj.art-bd8a6a88362c4625ba37d6c8bef17dce2022-12-22T00:39:18ZengFrontiers Media S.A.Frontiers in Microbiology1664-302X2022-06-011310.3389/fmicb.2022.909109909109Reduction Kinetic of Water Soluble Metal Salts by Geobacter sulfurreducens: Fe2+/Hemes Stabilize and Regulate Electron Flux RatesMaksym Karamash0Michael Stumpe1Jörn Dengjel2Carlos A. Salgueiro3Carlos A. Salgueiro4Bernd Giese5Katharina M. Fromm6Department of Chemistry, University of Fribourg, Fribourg, SwitzerlandDepartment of Biology, University of Fribourg, Fribourg, SwitzerlandDepartment of Biology, University of Fribourg, Fribourg, SwitzerlandAssociate Laboratory i4HB – Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, Costa da Caparica, PortugalUCIBIO – Applied Molecular Biosciences Unit, Chemistry Department, School of Science and Technology, NOVA University Lisbon, Costa da Caparica, PortugalDepartment of Chemistry, University of Fribourg, Fribourg, SwitzerlandDepartment of Chemistry, University of Fribourg, Fribourg, SwitzerlandGeobacter sulfurreducens is a widely applied microorganism for the reduction of toxic metal salts, as an electron source for bioelectrochemical devices, and as a reagent for the synthesis of nanoparticles. In order to understand the influence of metal salts, and of electron transporting, multiheme c-cytochromes on the electron flux during respiration of G. sulfurreducens, the reduction kinetic of Fe3+, Co3+, V5+, Cr6+, and Mn7+ containing complexes were measured. Starting from the resting phase, each G. sulfurreducens cell produced an electron flux of 3.7 × 105 electrons per second during the respiration process. Reduction rates were within ± 30% the same for the 6 different metal salts, and reaction kinetics were of zero order. Decrease of c-cytochrome concentrations by downregulation and mutation demonstrated that c-cytochromes stabilized respiration rates by variation of their redox states. Increasing Fe2+/heme levels increased electron flux rates, and induced respiration flexibility. The kinetic effects parallel electrochemical results of G. sulfurreducens biofilms on electrodes, and might help to optimize bioelectrochemical devices.https://www.frontiersin.org/articles/10.3389/fmicb.2022.909109/fullreaction kineticc-cytochromeGeobacter sulfurreducensremediationbioelectrochemistry |
| spellingShingle | Maksym Karamash Michael Stumpe Jörn Dengjel Carlos A. Salgueiro Carlos A. Salgueiro Bernd Giese Katharina M. Fromm Reduction Kinetic of Water Soluble Metal Salts by Geobacter sulfurreducens: Fe2+/Hemes Stabilize and Regulate Electron Flux Rates Frontiers in Microbiology reaction kinetic c-cytochrome Geobacter sulfurreducens remediation bioelectrochemistry |
| title | Reduction Kinetic of Water Soluble Metal Salts by Geobacter sulfurreducens: Fe2+/Hemes Stabilize and Regulate Electron Flux Rates |
| title_full | Reduction Kinetic of Water Soluble Metal Salts by Geobacter sulfurreducens: Fe2+/Hemes Stabilize and Regulate Electron Flux Rates |
| title_fullStr | Reduction Kinetic of Water Soluble Metal Salts by Geobacter sulfurreducens: Fe2+/Hemes Stabilize and Regulate Electron Flux Rates |
| title_full_unstemmed | Reduction Kinetic of Water Soluble Metal Salts by Geobacter sulfurreducens: Fe2+/Hemes Stabilize and Regulate Electron Flux Rates |
| title_short | Reduction Kinetic of Water Soluble Metal Salts by Geobacter sulfurreducens: Fe2+/Hemes Stabilize and Regulate Electron Flux Rates |
| title_sort | reduction kinetic of water soluble metal salts by geobacter sulfurreducens fe2 hemes stabilize and regulate electron flux rates |
| topic | reaction kinetic c-cytochrome Geobacter sulfurreducens remediation bioelectrochemistry |
| url | https://www.frontiersin.org/articles/10.3389/fmicb.2022.909109/full |
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