1,1,1,2,1,- 1Università degli Studi di Napoli Federico II, Biology, Napoli, Italy
- 2Department of Marine and Coastal Science, Rutgers University, New Brunswick, NJ, USA
- 3Woods Hole Oceanographic Institution, Woods Hole, MA, USA
- 4Environmental Science, University of Southern California, Los Angeles, CA, USA
- 5Instituto de Ciencias Marinas y Limnológicas, Universidad Austral de Chile, Valdivia, Chile & Center for Oceanographic Research COPAS COASTAL, Universidad de Concepción, Valdivia, Chile
- 6Instituto de Bio y Geociencias del Noroeste Argentino (IBIGEO, CONICET-UNSa), Salta, Argentina
- 7Observatorio Vulcanológico y Sismológico de Costa Rica, Universidad Nacional, Heredia, Costa Rica
- 8Department of Earth and Planetary Sciences, University of New Mexico, Albuquerque, NM, USA
- 9Servicio Geológico Ambiental, Heredia, Costa Rica
- 10Institute of Marine Biological Resources and Biotechnologies, National Research Council, Ancona, Italy
- *A full list of authors appears at the end of the abstract
Transition metals are crucial for microbial metabolism, serving as catalytic cofactors in many enzymes and contributing to protein folding. Their fluctuating bioavailability, depending on environmental concentrations and redox state, but also their potential toxicity due to high reactivity, selected for tight metal homeostasis regulation. Metal transporters lie at the core of this homeostatic control. Accordingly, microorganisms have evolved a wide diversity of metal transport systems to cope with changing environmental metal availability throughout Earth history.
The present study aims at describing the diversity and distribution of microbial metal transport systems across several geothermal environments, with a specific focus on shallow water hydrothermal vents and terrestrial deeply sourced seeps. In these ecosystems, microbial diversity and metabolism are tightly linked to the elements supplied by water-rock interactions, providing an excellent model to investigate the diversity of microbial metal transport systems.
We performed shotgun metagenomics of geofluids from more than 200 thermal features globally distributed and carried out functional annotation of sequencing reads using a manually curated database of metal transport genes. Metagenomic data were coupled to high-resolution geochemical analysis, including ion chromatography and inductively-coupled plasma mass spectrometry.
Our results reveal that microbial metal transport systems are strongly structured by geochemical context and dissolved metal availability across geothermal environments. Transporter diversity and abundance varied systematically across tectonic settings and physicochemical gradients, with metal-poor environments exhibiting higher diversity and abundance of uptake systems, whereas metal-rich and acidic environments display reduced transporter diversity and a relative enrichment of efflux-related functions. These relationships point to a dynamic regulatory mechanism, where microorganisms may adapt their metal uptake strategies in response to fluctuating metal concentrations, providing new insights into microbial evolution of metal transport systems. Such findings could have broader implications for understanding microbial evolution in extreme environments, providing more insights into the fundamental role of metal availability in the regulation of microbial diversity.
Flavia Migliaccio, Davide Corso, Martina Cascone, Edoardo Taccaliti, Benoit de Pins, Deborah Bastoni, Matteo Selci, Gabriella Gallo, Alessia Bastianoni, Bernardo Barosa, Feliciana Oliva, Annarita Ricciardelli, Monica Correggia, Luciano di Iorio, Angelina Cordone, Donato Giovannelli
How to cite: Migliaccio, F., Corso, D., Cascone, M., Taccaliti, E., De Pins, B., Bastoni, D., Selci, M., Gallo, G., Bastianoni, A., Di Iorio, L., Vetriani, C., Barry, P. H., Tyne, R. L., Lloyd, K. G., Jessen, G. L., Chiodi, A., De Moor, M. J., Ramirez, C. J., Cordone, A., and Giovannelli, D. and the Giovannelli Lab - Università degli Studi di Napoli Federico II, Department of Biology: Environmental drivers of microbial metal transporter diversity in geothermal systems, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-13876, https://doi.org/10.5194/egusphere-egu26-13876, 2026.
