title: Ecological succession leads to chemosynthesis in mats colonizing wood in sea water.
abstract: Chemosynthetic mats involved in cycling sulfur compounds are often found in hydrothermal vents, cold seeps and whale falls. However, there are only few records of wood fall mats, even though the presence of hydrogen sulfide at the wood surface should create a perfect niche for sulfide-oxidizing bacteria. Here we report the growth of microbial mats on wood incubated under conditions that simulate the Mediterranean deep-sea temperature and darkness. We used amplicon and metagenomic sequencing combined with fluorescence in situ hybridization to test whether a microbial succession occurs during mat formation and whether the wood fall mats present chemosynthetic features. We show that the wood surface was first colonized by sulfide-oxidizing bacteria belonging to the Arcobacter genus after only 30 days of immersion. Subsequently, the number of sulfate reducers increased and the dominant Arcobacter phylotype changed. The ecological succession was reflected by a change in the metabolic potential of the community from chemolithoheterotrophs to potential chemolithoautotrophs. Our work provides clear evidence for the chemosynthetic nature of wood fall ecosystems and demonstrates the utility to develop experimental incubation in the laboratory to study deep-sea chemosynthetic mats.
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, CNRS, Laboratoire d'Ecogeochimie des Environnements Benthiques (LECOB), Observatoire Océanologique, Banyuls sur Mer, France.
authors.forename: Dimitri
authors.initials: D
authors.lastname: Kalenitchenko
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, CNRS, Laboratoire d'Ecogeochimie des Environnements Benthiques (LECOB), Observatoire Océanologique, Banyuls sur Mer, France.
authors.forename: Marlène
authors.initials: M
authors.lastname: Dupraz
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, CNRS, Laboratoire d'Ecogeochimie des Environnements Benthiques (LECOB), Observatoire Océanologique, Banyuls sur Mer, France.
authors.forename: Nadine
authors.initials: N
authors.lastname: Le Bris
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, CNRS, Observatoire Océanologique de Banyuls (OOB), Banyuls sur Mer, France.
authors.forename: Carole
authors.initials: C
authors.lastname: Petetin
authors.affiliation: UMR EEF INRA/UL, Plateforme Technique d'Ecologie et d'Ecophysiologie Forestières (PTEF), INRA-LORRAINE, Champenoux, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Rose
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, CNRS, Observatoire Océanologique de Banyuls (OOB), Banyuls sur Mer, France.
authors.forename: Nyree J
authors.initials: NJ
authors.lastname: West
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, CNRS, Laboratoire d'Ecogeochimie des Environnements Benthiques (LECOB), Observatoire Océanologique, Banyuls sur Mer, France.
authors.forename: Pierre E
authors.identifier: 0000-0002-2238-3247
authors.initials: PE
authors.lastname: Galand
mesh_terms: D020640:Arcobacter / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D001419:Bacteria / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D004463:Ecology; D017753:Ecosystem; D006862:Hydrogen Sulfide / Q000378:metabolism; D017404:In Situ Hybridization, Fluorescence; D008522:Mediterranean Sea; D012623:Seawater / Q000382:microbiology*; D017422:Sequence Analysis, DNA; D013440:Sulfides / Q000378:metabolism; D014871:Water Microbiology; D014934:Wood / Q000737:chemistry / Q000382:microbiology*
chemical_list: D013440:Sulfides; D006862:Hydrogen Sulfide