Olivine weathering by the genetically amenable rock-inhabiting fungus Knufia petricola A95
- In arid sun-exposed environments, rock-inhabiting fungi dominate microbial communities on rock surfaces. Fungi are known to enhance rock weathering, although the exact mechanisms are not completely understood. These natural processes can be simulated by reproducible experimental systems. Particularly attractive are genetically amenable rock-weathering fungi, where certain traits can be knocked-out to identify weathering-relevant functions. Here, we studied the effect of the rock-inhabiting fungus Knufia petricola A95 and its melanin-deficient mutant (ΔKppks) on the weathering of a Fe-bearing olivine. We examined the olivine dissolution kinetics and looked at the olivine-fungus interface. For the former we inoculated olivine powder with the fungus in batch and mixed flow reactors and analysed the medium solution by ICP-OES, for the latter biofilm-covered olivine sections from flow-through reactors were analysed by FIB-TEM.
In general olivine dissolution was lower when olivine wasIn arid sun-exposed environments, rock-inhabiting fungi dominate microbial communities on rock surfaces. Fungi are known to enhance rock weathering, although the exact mechanisms are not completely understood. These natural processes can be simulated by reproducible experimental systems. Particularly attractive are genetically amenable rock-weathering fungi, where certain traits can be knocked-out to identify weathering-relevant functions. Here, we studied the effect of the rock-inhabiting fungus Knufia petricola A95 and its melanin-deficient mutant (ΔKppks) on the weathering of a Fe-bearing olivine. We examined the olivine dissolution kinetics and looked at the olivine-fungus interface. For the former we inoculated olivine powder with the fungus in batch and mixed flow reactors and analysed the medium solution by ICP-OES, for the latter biofilm-covered olivine sections from flow-through reactors were analysed by FIB-TEM.
In general olivine dissolution was lower when olivine was incubated without fungi: the abiotic olivine dissolution rates were lowest and the surface of the abiotically reacted olivine sections showed no etching. Various chemical analyses show Fe (oxyhydr)oxide precipitation on top of the abiotically reacted olivine, indicating its role in inhibiting olivine dissolution. Both the wild type (WT) and ΔKppks solubilised and bound significant amounts of Fe released by olivine dissolution. Fe (oxyhydr)oxide precipitation was thus reduced, explaining the enhanced olivine dissolution in their presence. Particularly efficient at preventing Fe precipitation were attached WT cells: the inhibition of olivine dissolution almost completely disappeared. The attachment capacity of the WT is most likely caused by the production of WT-specific extracellular polymeric substances. Our presented experimental systems allowed the precipitation of Fe (oxyhydr)oxides and included a rock-inhabiting fungus and thus simulated weathering processes relevant to natural ecosystems.…
Autor*innen: | Ruben GerritsORCiD |
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Weitere Person: | R. Pokharel, Romy Breitenbach, Jörg RadnikORCiD, R. Wirth, J. A. Schuessler, L. G. Benning, F. von Blanckenburg, Anna GorbushinaORCiD, Ines FeldmannORCiD |
Dokumenttyp: | Vortrag |
Veröffentlichungsform: | Präsentation |
Sprache: | Englisch |
Jahr der Erstveröffentlichung: | 2019 |
Organisationseinheit der BAM: | 4 Material und Umwelt |
4 Material und Umwelt / 4.0 Abteilungsleitung und andere | |
4 Material und Umwelt / 4.2 Material-Mikrobiom Wechselwirkungen | |
6 Materialchemie | |
6 Materialchemie / 6.1 Oberflächen- und Dünnschichtanalyse | |
DDC-Klassifikation: | Technik, Medizin, angewandte Wissenschaften / Ingenieurwissenschaften / Sanitär- und Kommunaltechnik; Umwelttechnik |
Freie Schlagwörter: | Fungus; Olivine; Weathering |
Themenfelder/Aktivitätsfelder der BAM: | Umwelt |
Umwelt / Umwelt-Material-Interaktionen | |
Veranstaltung: | ISEB 2019 |
Veranstaltungsort: | Potsdam, Germany |
Beginndatum der Veranstaltung: | 23.09.2019 |
Enddatum der Veranstaltung: | 27.09.2019 |
Verfügbarkeit des Dokuments: | Datei im Netzwerk der BAM verfügbar ("Closed Access") |
Datum der Freischaltung: | 21.11.2019 |
Referierte Publikation: | Nein |
Eingeladener Vortrag: | Nein |