Mineral spring water biofilms Metagenome

These peculiar pendant biofilms represent, to our knowledge, the first snottites described to hostseveral dominating methanotrophic taxa along with a rich diversity of associated bacteria. Wespeculate that the buildup of the massive EPS matrix serves both as electron sink, but also asdiffusive barrier against harmful iodine species potentially volatilized in the cave.The submersed wall biofilms have been shown to host the highest abundance of knownmethanotrophic taxa. Lab experiments on potential methane oxidation rates and 13 C isotopicsignatures clearly prove that thermogenic methane is the sole carbon source for these communities.Whereas Archaea seem to be absent in the subaerial biofilms, we also have preliminary evidence forthe presence of Archaea in these samples.The mineral spring water has been used for medical purposes before the Second World War dueto its high iodine concentrations.PI Tillman Lueders Institute of Groundwater Ecology, Helmholtz Zentrum Munchen