Microbial aquatic roommates: Woesearchaeota and photosynthetic organisms in a lake – MARWEL

The MARWEL project proposes to unravel specific genomic adaptations and interactions related to Woesearchaeota ecology. Indeed, we benefit from a unique case study in an extreme microbial lacustrine ecosystem in which previous work reported a strong niche partitioning of Woesearchaeota between a free-living lifestyle and an associated lifestyle to photosynthetic microorganisms (i.e. the cyanobacteria Arthrospira fusiformis and/or the picoeukaryote Picocystis salinarum). Using an original microbial cytometry cell-sorting coupled to meta-omics approaches (metagenomics and metatranscriptomics), we aim at (1) deciphering which genomic specificities of Woesearchaeota are related to free-living or associated lifestyle and (2) to evidence the type of interactions that took place at the microscale (i.e. phycosphere) in the case of Woesearchaeota associated with photosynthetic members, A. fusiformis and/or P. salinarum.