Ifremer - Laboratoire de Microbiologie des Environnements Extrêmes

This study investigates the influences of minerals and microorganisms on fluid chemistry through a continuous enrichment culture experiment conducted in a gas-lift bioreactor during the MoMARsat’19 cruise. The physico-chemical conditions of the bioreactor tended to mimic the in situ conditions of diffuse vents (anaerobiosis, 80 °C, and pH ∼6.5). A sulfate-based chimney (inoculum) and buoyant hydrothermal fluid were both collected in situ at the Aisics vent and incubated for 18 days. In this study, we present the elemental, Sr, and Li isotopic composition of the fluid medium, alongside the microbial diversity (Bacteria and Archaea) detected during the experiment.