Publications associées à Phenotypic heterogeneity driven by nutrient limitation promotes growth in fluctuating environments

The microbial genomics of glacier-fed streams: adaptations to an extreme ecosystem

Glacier-fed streams are the cold, ultra-oligotrophic, and unstable streams that are fed by glacial meltwater. Despite these extreme conditions, they harbour a diverse and abundant microbial diversity that develops into biofilms, covering the boulders and s ...

EPFL2024

Winter post-droughts amplify extreme nitrate concentrations in German rivers

Jana Freiin von Freyberg

Hydrological extremes can affect nutrient export from catchments to streams, posing a threat to aquatic ecosystems. In this study, we investigated the effects of hydrological drought on nitrate concentrations in the streamflow of 182 German catchments from ...

Iop Publishing Ltd2024

Reconstruction and analysis of genome-scale metabolic networks in single organisms and microbial communities

Evangelia Vagena

Microorganisms are a key component in the chain of life. They are essential for agriculture, produce a large proportion of oxygen, and play a central role in the cycle of elements. Microorganisms are widely used in the production of food and alcoholic beve ...

EPFL2024

Coupled carbon and nitrogen cycling regulates the cnidarian–algal symbiosis

Anders Meibom, Stéphane Laurent Escrig, Nils Rädecker

Efficient nutrient recycling underpins the ecological success of cnidarian-algal symbioses in oligotrophic waters. In these symbioses, nitrogen limitation restricts the growth of algal endosymbionts in hospite and stimulates their release of photosynthates ...

Nature Research2023

Symbiotic nutrient cycling enables the long-term survival of Aiptasia in the absence of heterotrophic food sources

Anders Meibom, Nils Rädecker

Phototrophic Cnidaria are mixotrophic organisms that can complement their het- erotrophic diet with nutrients assimilated by their algal endosymbionts. Metabolic mod- els suggest that the translocation of photosynthates and their derivatives from the algae ...

2023

Food web structure and energy flux dynamics, but not taxonomic richness, influence microbial ecosystem functions in a Sphagnum-dominated peatland

Alexandre Buttler, Edward Mitchell, Vincent Eric Jules Jassey

Soil microbial communities are vital for multiple ecosystem processes and services. In particular, soil microbial food webs are key determinants of soil biodiversity, functioning and stability. Unclear, however, is how struc-tural features of food webs, su ...

ELSEVIER FRANCE-EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER2023

Excess labile carbon promotes diazotroph abundance in heat-stressed octocorals

Claudia Isabella Pogoreutz

Nitrogen limitation is the foundation of stable coral-algal symbioses. Diazotrophs, prokaryotes capable of fixing N-2 into ammonia, support the productivity of corals in oligotrophic waters, but could contribute to the destabilization of holobiont function ...

ROYAL SOC2023

Metabolic Performance and Fate of Electrons during Nitrate-Reducing Fe(II) Oxidation by the Autotrophic Enrichment Culture KS Grown at Different Initial Fe/N Ratios

Natalia Jakus

Autotrophic nitrate-reducing Fe(II)-oxidizing (NRFeOx) microorganisms fix CO2 and oxidize Fe(II) coupled to denitrification, influencing carbon, iron, and nitrogen cycles in pH-neutral, anoxic environments. However, the distribution of electrons from Fe(II ...

AMER SOC MICROBIOLOGY2023

Metabolism of the symbiotic jellyfish Cassiopea in a changing environment

Gaëlle Delphine Toullec

Ocean warming and other anthropogenic impacts have led to a global decline in many photosymbiotic cnidarians, most notably reef-building corals. But some species of the symbiotic and (sub-)tropical upside-down jellyfish Cassiopea are increasingly reported ...

EPFL2023

Contrasting Microbiome Dynamics of Putative Denitrifying Bacteria in Two Octocoral Species Exposed to Dissolved Organic Carbon (DOC) and Warming

Nils Rädecker, Claudia Isabella Pogoreutz

Mutualistic nutrient cycling in the coral-algae symbiosis depends on limited nitrogen (N) availability for algal symbionts. Denitrifying prokaryotes capable of reducing nitrate or nitrite to dinitrogen could thus support coral holobiont functioning by limi ...

2022

A roadmap to understanding diversity and function of coral reef-associated fungi

Claudia Isabella Pogoreutz

Tropical coral reefs are hotspots of marine productivity, owing to the association of reef-building corals with endosymbiotic algae and metabolically diverse bacterial communities. However, the functional importance of fungi, well-known for their contribut ...

OXFORD UNIV PRESS2022

Influence of Microplastics on Microbial Structure, Function, and Mechanical Properties of Stream Periphyton

Renata Behra, Kristin Schirmer, Ahmed Tlili

Periphyton is a freshwater biofilm composed of prokaryotic and eukaryotic communities that occupy rocks and sediments, forming the base of the food web and playing a key role in nutrient cycling. Given the large surface that periphyton comprises, it may al ...

FRONTIERS MEDIA SA2022

Wastewater microorganisms impact microbial diversity and important ecological functions of stream periphyton

Kristin Schirmer, Ahmed Tlili

Effluents of wastewater treatment plants can impact microbial communities in the receiving streams. However, little is known about the role of microorganisms in wastewater as opposed to other wastewater constituents, such as nutrients and micropollutants. ...

Pergamon-Elsevier Science Ltd2022

Glacier shrinkage will accelerate downstream decomposition of organic matter and alters microbiome structure and function

Nicola Deluigi, Leïla Ezzat, Vincent Henri De Staercke, Tom Ian Battin, Paraskevi Pramateftaki, Hannes Markus Peter, Jade Brandani, Matteo Tolosano, Michail Styllas, Tyler Joe Kohler, Stylianos Fodelianakis, Massimo Bourquin, Martina Andrea Schön, Susheel Bhanu Busi, Grégoire Marie Octave Edouard Michoud

The shrinking of glaciers is among the most iconic consequences of climate change. Despite this, the downstream consequences for ecosystem processes and related microbiome structure and function remain poorly understood. Here, using a space-for-time substi ...

Wiley2022

Genomic and metabolic adaptations of biofilms to ecological windows of opportunity in glacier-fed streams

Leïla Ezzat, Vincent Henri De Staercke, Tom Ian Battin, Paraskevi Pramateftaki, Hannes Markus Peter, Matteo Tolosano, Michail Styllas, Tyler Joe Kohler, Stylianos Fodelianakis, Massimo Bourquin, Martina Andrea Schön, Susheel Bhanu Busi, Grégoire Marie Octave Edouard Michoud

In glacier-fed streams, ecological windows of opportunity allow complex microbial biofilms to develop and transiently form the basis of the food web, thereby controlling key ecosystem processes. Using metagenome-assembled genomes, we unravel strategies tha ...

Springer2022

Regimes of primary production and their drivers in Alpine streams

Mélanie Clémençon, Tom Ian Battin, Amber Joy Ulseth, Marta Boix Canadell, Luis Gómez Gener

Primary production is a fundamental ecosystem process that influences nutrient and carbon cycling, and trophic structure in streams. The magnitude and timing of gross primary production (GPP) are typically controlled by hydrology, light, nutrient availa ...

2021

Heat stress reduces the contribution of diazotrophs to coral holobiont nitrogen cycling

Anders Meibom, Nils Rädecker, Claudia Isabella Pogoreutz, Gabriela Hannah Holligan Perna

Efficient nutrient cycling in the coral-algal symbiosis requires constant but limited nitrogen availability. Coral-associated diazotrophs, i.e., prokaryotes capable of fixing dinitrogen, may thus support productivity in a stable coral-algal symbiosis but c ...

2022

Robust and sustainable cultivation of microalgae: recycling of nitrogen from liquid digestate and control of biological contamination

Adrian Pulgarin

The present doctoral thesis aimed to achieve a robust cultivation of microalgae by recycling nitrogen from a liquid digestate. However, the use of non-sterile nutrient source increases the risks of contamination of undesired organisms such as bacteria, vir ...

EPFL2021

The influence of the crowding assumptions in biofilm simulations

Vassily Hatzimanikatis, Liliana Angeles Martinez

Author summary In nature, many organisms grow in crowded biofilms that protect against stressful conditions, making their control/eradication a challenge. Modeling these microbial systems is a valuable tool for studying the interactions among cells and exp ...

2021

High plasticity of nitrogen fixation and denitrification of common coral reef substrates in response to nitrate availability

Nils Rädecker, Hal Hunt Jones II

Nitrogen cycling in coral reefs may be affected by nutrient availability, but knowledge about concentration-dependent thresholds that modulate dinitrogen fixation and denitrification is missing. We determined the effects of different nitrate concentrations ...

2021