UPPA Associated Professor Awarded Prestigious Fulbright Grant6 months of Research in Chicago

Marie-Pierre Isaure, Associate Professor in Geochemistry at IPREM Laboratory in Pau, was awarded a Fulbright grant, which allows a dozen French researchers to spend time each year in the United States. She worked at Argonne National Laboratory in Chicago from March to September 2022.

Marie-Pierre Isaure's research focuses on the fate of metals in the environment, and their interactions with microorganisms and plants, in order to understand their toxicity. To this end, the localization of metals at the cellular level is a key factor, and techniques derived from synchrotron radiation offer new perspectives in terms of spatial resolution and detection of trace elements.

The research project aimed to develop a nanoscale imaging approach in environmental sciences. Collaboration with American researchers at the Advanced Photon Source (APS) synchrotron has made it possible to set up a correlative multi-modal cryogenic imaging approach – which makes it possible to preserve the structure of samples, the distribution of elements and their physicochemical forms (speciation) – combining optical fluorescence and X-ray nano-fluorescence on the scale of a single bacterial cell.

Bionanoprobe Beam Line on which nano-imaging in cryogenic mode has been developed.

Researchers were particularly interested in the transformation of mercury by bacteria living in anoxic sediments. These bacteria produce methylmercury, a powerful neurotoxicant that is biomagnified and bioaccumulated in the trophic chain, ultimately posing a risk to human and environmental health. Deciphering the transformations of mercury at the bacterial cell level allows to better understand its toxicity and its fate in natural environments.

This research trip resulted from E2S UPPA project “Go BEAM,” and cooperation between the two teams is bound to grow thanks to a Franco-American project (Nano X-Ilight), a French National Research Agency (ANR) project (MicroMer) and the involvement of several French and American students/post-docs.

Marie-Pierre Isaure also met researchers from Northwestern University, a privileged partner of UPPA, with whom collaborations should be initiated in this area of research.