Magnetic organelle gene clusters enable bacterial growth and ATP homeostasis under oxidizing conditions
Year: 2026
Type: preprint
Abstract: Biological organisms can produce magnetic nanoparticles made of magnetite to detect the Earth's magnetic field for orientation. The evolutionary mechanisms that led to the acquisition of this capacity remain unknown. The most ancient organisms known to perform magnetic orientation are magnetotactic bacteria. Under tight genetic control, they produce chains of magnetite nanoparticles in dedicated organelles to allow efficient navigation in aquatic environments containing molecular oxygen. Yet, these bacteria have been proposed to emerge before molecular oxygen became abundant on Earth, at a time when this navigation system could not have served its current function. Here, we show that gene clusters responsible of magnetite formation and organization enable resistance against hydrogen peroxide, a toxic oxygen-derived compound that was produced during the early stages of Earth's oxygenation when iron oxidation consumed molecular oxygen. Characterization of the nanoparticle's oxidation state supported the involvement of magnetite in resistance to hydrogen peroxide-induced oxidative stress. These findings are compatible with an early emergence of magnetotactic bacteria, before natural waters became oxygenated. We propose a conceptual framework to explain the origin of magnetic orientation in bacteria, and offer tools to identify the initiation of Earth's oxygenation in a time-resolved manner.
Authors: Mila Kojadinovic-Sirinelli, Mélissa Garry, Juan Wan, Agnès Dumont, Ramon Egli, Julie Carlut, Laurent Modolo, Daniel M. Chevrier, Lourdes Marcano, Fadi Choueikani, Christophe Gatel, Ingrid Marie Andersen, Ernesto Scoppola, Chenghao Li, Catherine Brutesco, Mathilde Nonnon, Emilie Gachon, Gael Yvert, Aurèle Piazza, Damien Faivre, Arash Komeili, Matthieu Amor
Institutions: Aix-Marseille Université, École Normale Supérieure de Lyon, Chinese Academy of Sciences, Lyon 1 Université, Centre National de la Recherche Scientifique, Inserm, Laboratoire de Biologie et Modélisation de la Cellule, GeoSphere Austria, Institut de physique du globe de Paris, Institut de Biosciences et Biotechnologies, Institut de Biosciences et biotechnologies d'Aix-Marseille, Universidad de Oviedo, Synchrotron SOLEIL, Université de Toulouse, Centre d’Élaboration de Matériaux et d’Études Structurales, Max Planck Institute of Colloids and Interfaces, University of California, Berkeley
Language: English
Subfield: Geophysics
Field: Earth and Planetary Sciences
Domain: Physical Sciences
Open Access status: green
Funder: Agence Nationale de la Recherche
OpenAlex ID: W7225562616