The possible occurrence of iron-dependent anaerobic methane oxidation in an Archean Ocean analogue

Fleur A.E. Roland, Alberto V. Borges, François Darchambeau, Marc Llirós, Jean Pierre Descy, Cédric Morana

Résultats de recherche: Contribution à un journal/une revueArticleRevue par des pairs

Résumé

In the ferruginous and anoxic early Earth oceans, photoferrotrophy drove most of the biological production before the advent of oxygenic photosynthesis, but its association with ferric iron (Fe3+) dependent anaerobic methane (CH4) oxidation (AOM) has been poorly investigated. We studied AOM in Kabuno Bay, a modern analogue to the Archean Ocean (anoxic bottom waters and dissolved Fe concentrations > 600 µmol L−1). Aerobic and anaerobic CH4 oxidation rates up to 0.12 ± 0.03 and 51 ± 1 µmol L−1 d−1, respectively, were put in evidence. In the Fe oxidation–reduction zone, we observed high concentration of Bacteriochlorophyll e (biomarker of the anoxygenic photoautotrophs), which co-occurred with the maximum CH4 oxidation peaks, and a high abundance of Candidatus Methanoperedens, which can couple AOM to Fe3+ reduction. In addition, comparison of measured CH4 oxidation rates with electron acceptor fluxes suggest that AOM could mainly rely on Fe3+ produced by photoferrotrophs. Further experiments specifically targeted to investigate the interactions between photoferrotrophs and AOM would be of considerable interest. Indeed, ferric Fe3+-driven AOM has been poorly envisaged as a possible metabolic process in the Archean ocean, but this can potentially change the conceptualization and modelling of metabolic and geochemical processes controlling climate conditions in the Early Earth.

langue originaleAnglais
Numéro d'article1597
journalScientific Reports
Volume11
Numéro de publication1
Les DOIs
Etat de la publicationPublié - janv. 2021
Modification externeOui

Empreinte digitale Examiner les sujets de recherche de « The possible occurrence of iron-dependent anaerobic methane oxidation in an Archean Ocean analogue ». Ensemble, ils forment une empreinte digitale unique.

Contient cette citation