Research - New entrants - 2026

Some microorganisms can use electricity in much the same way humans use food: as a source of energy. Some of them are even able to take electrons directly from an electrode and use this energy to transform carbon dioxide (CO₂) into useful molecules. This process, called microbial electrosynthesis, is a promising technology for producing sustainable fuels, chemicals, and materials from renewable electricity while recycling CO₂. However, current systems rely on a very limited number of known microorganisms, which strongly restricts what can be produced and under which conditions.

This project aims to unlock a largely unexplored biological resource: polyextremophilic microorganisms. These microbes live in extreme environments such as high temperature, high salinity, or extreme pH, for example in deep-sea hydrothermal vents. Recent research suggests that such organisms could greatly expand the range of molecules that can be produced by microbial electrosynthesis, and operate under conditions where conventional microbes fail.

To achieve this, the project develops a new generation of low-cost, miniaturized, and automated electrosynthesis reactors using 3D printing and open-source electronics. Unlike existing systems that are very expensive and scarce, these devices make it possible to rapidly test many extreme conditions in parallel. Hydrothermal vent samples collected during oceanographic campaigns will be enriched, screened, and analyzed to identify new electricity-using microorganisms and microbial communities.

Ultimately, the project seeks to isolate new strains capable of converting CO₂ and electricity into valuable products such as bioplastics, organic acids, alcohols, or energy carriers. Beyond its biotechnological potential, this work will open a new field of research at the intersection of microbiology, electrochemistry, and extreme environments, with implications for sustainable industry, deep-sea ecology, and even future space exploration.

In photosynthetic organisms, light absorption is essential for growth. Absorbed in excess however, it leads to cell damage. These organisms have thus developed a large array of photoprotective mechanisms, most of which target light-harvesting antennae. In plants, the main antenna is the Light-Harvesting Complex II (LHCII), a trimer of membrane, pigment-binding proteins, which is thus at the heart of the critical trade-off between light harvesting and photoprotection. There is a long-standing debate over the triggers of photoprotection and their effect on LHCII’s switch between light-harvesting and energy dissipative states. Yet, understanding this switch and its regulation is of major importance for fields ranging from crop stress resilience to reduction of energy loss in biotechnological applications.

This project aims to investigate which light acclimation-induced changes on the plant light-harvesting complex regulate its ability to cluster and / or interact with other complexes, and thus to modulate light capture and energy dissipation.

Our preliminary research has indeed evidenced a change in clustering properties of LHCII between complexes purified from dark- and light-adapted plants. Yet, an array of modifications on LHCII or its immediate surroundings, well-known (carotenoids) or little explored (lipids, surface charges modifications) can explain the change. Using biochemistry, fluorescence spectroscopy, and to some extent genetics and structural biology, we are now investigating if each of these parameters influences LHCII interacting properties – and how!

The genus Neisseria provides an especially informative model for understanding how evolution reshapes bacterial “lifestyles”. Within the same genus, some species are primarily commensal, whereas others are pathogens capable of causing infection. The project starts from a simple idea: before a bacterium can become pathogenic, it must first pass through key steps such as adapting to a new environmental niche. Moving from one environment to another (for example, from the oral cavity to the nasopharynx, or from one colonization site to another) exposes bacteria to new chemical constraints and immune pressures.

At the core of the study are two selective pressures. The first is copper homeostasis: copper is essential at low levels but becomes toxic when in excess. The second is redox stress (oxidative and nitrosative), often linked to host defense mechanisms, which can damage proteins and disrupt metabolism. The project investigates the hypothesis that, over the course of Neisseria evolution, these two responses have been “rewired”. Instead of being controlled by the canonical copper regulator CueR, the expression of key copper-export genes may have shifted under the control of NmlR, a regulator associated with the redox stress response. Such a reorganization would more tightly couple copper detoxification with resistance to oxidative stress potentially providing an advantage during niche transitions and, indirectly, affecting the ability to cause disease.

To test this hypothesis, we will compare many Neisseria species, experimentally characterize how CueR and NmlR function, and then swap regulatory modules between species to assess causally the impact on copper tolerance, redox-stress resistance, and survival in the presence of immune cells. The ultimate goal is to determine whether certain traits associated with pathogenesis primarily reflect ecological adaptation to new niches, rather than an intrinsic link to virulence.