title: Functional interactions among filamentous Epsilonproteobacteria and Bacteroidetes in a deep-sea hydrothermal vent biofilm.
abstract: Little is known about how lithoautotrophic primary production is connected to microbial organotrophic consumption in hydrothermal systems. Using a multifaceted approach, we analysed the structure and metabolic capabilities within a biofilm growing on the surface of a black smoker chimney in the Loki's Castle vent field. Imaging revealed the presence of rod-shaped Bacteroidetes growing as ectobionts on long, sheathed microbial filaments (> 100 μm) affiliated with the Sulfurovum genus within Epsilonproteobacteria. The filaments were composed of a thick (> 200 nm) stable polysaccharide, representing a substantial fraction of organic carbon produced by primary production. An integrated -omics approach enabled us to assess the metabolic potential and in situ metabolism of individual taxonomic and morphological groups identified by imaging. Specifically, we provide evidence that organotrophic Bacteroidetes attach to and glide along the surface of Sulfurovum filaments utilizing organic polymers produced by the lithoautotrophic Sulfurovum. Furthermore, in situ expression of acetyl-CoA synthetase by Sulfurovum suggested the ability to assimilate acetate, indicating recycling of organic matter in the biofilm. This study expands our understanding of the lifestyles of Epsilonproteobacteria in hydrothermal vents, their metabolic properties and co-operative interactions in deep-sea hydrothermal vent food webs.
authors.affiliation: Centre for Geobiology.|Department of Biology, University of Bergen, Allegaten 41, 5020, Bergen, Norway.
authors.forename: Runar
authors.initials: R
authors.lastname: Stokke
authors.affiliation: Centre for Geobiology.|Department of Biology, University of Bergen, Allegaten 41, 5020, Bergen, Norway.
authors.forename: Håkon
authors.initials: H
authors.lastname: Dahle
authors.affiliation: Centre for Geobiology.|Department of Biology, University of Bergen, Allegaten 41, 5020, Bergen, Norway.
authors.forename: Irene
authors.initials: I
authors.lastname: Roalkvam
authors.affiliation: Centre for Geobiology.|Department of Biology, University of Bergen, Allegaten 41, 5020, Bergen, Norway.
authors.forename: Juliane
authors.initials: J
authors.lastname: Wissuwa
authors.affiliation: Centre for Geobiology.|Department of Biology, University of Bergen, Allegaten 41, 5020, Bergen, Norway.
authors.forename: Frida Lise
authors.initials: FL
authors.lastname: Daae
authors.affiliation: Centre for Ecological and Evolutionary Synthesis, University of Oslo, Blindernveien 31, 0316, Oslo, Norway.
authors.forename: Ave
authors.initials: A
authors.lastname: Tooming-Klunderud
authors.affiliation: Centre for Geobiology.|Department of Earth Science, University of Bergen, Allegaten 41, 5020, Bergen, Norway.
authors.forename: Ingunn H
authors.initials: IH
authors.lastname: Thorseth
authors.affiliation: Centre for Geobiology.|Department of Earth Science, University of Bergen, Allegaten 41, 5020, Bergen, Norway.
authors.forename: Rolf B
authors.initials: RB
authors.lastname: Pedersen
authors.affiliation: Centre for Geobiology.|Department of Biology, University of Bergen, Allegaten 41, 5020, Bergen, Norway.
authors.forename: Ida Helene
authors.initials: IH
authors.lastname: Steen
mesh_terms: D000085:Acetates / Q000378:metabolism; D000105:Acetyl Coenzyme A / Q000096:biosynthesis; D041963:Bacteroidetes / Q000235:genetics / Q000502:physiology*; D018441:Biofilms; D003066:Coenzyme A Ligases / Q000096:biosynthesis / Q000378:metabolism*; D020565:Epsilonproteobacteria / Q000235:genetics / Q000502:physiology*; D060086:Hydrothermal Vents / Q000382:microbiology*; D056265:Microbial Interactions; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics
chemical_list: D000085:Acetates; D012336:RNA, Ribosomal, 16S; D000105:Acetyl Coenzyme A; D003066:Coenzyme A Ligases; C101958:acetate-CoA ligase (ADP-forming)