Anaïs Cario

Anaïs' keynote talk title is: Studying the deep biosphere in the lab: The challenge to stay under pressure

A majority of Earth’s prokaryotes reside in the deep biosphere (i.e. subsurface environments) where little is known about how inherent elevated pressures influence the underground geochemistry and the inhabiting microbial communities. Although some high-pressure experimental means exist, microbiology under extreme conditions is still scarcely studied. Indeed, conventional cultivation and analysis techniques offer limited in situ characterization, thus narrowing the ability to investigate deep subsurface microbial communities. 
This presentation will first introduce the deep biosphere and focus on how the high-pressure parameter matters to investigate deep microorganisms in the lab. Then, several multi- high-pressure approaches, that implement in situ characterization techniques, will be presented. These brand new devices allow overcoming the limitations due to decompression, providing ways for in situ investigations under pressure and fast screening capabilities. Thus, these high-pressure tools would enable working with larger and new deep biosphere isolates, and characterized them in terms of temperature range and growth pressure, this would shed light on their putative function in their natural habitat and in the geochemical cycles of their ecosystem.