Intracellular Oceanospirillales bacteria inhabit gills of Acesta bivalves.
A novel bacterium was discovered in the gills of the large bivalve Acesta excavata (Limidae) from coral reefs on the northeast Atlantic margin near the shelf break of the fishing ground Haltenbanken of Norway, and confirmed present in A. excavata from a rock-wall in the Trondheimsfjord. Purified gill DNA contained one dominant bacterial rRNA operon as indicated from analysis of broad range bacterial PCR amplicons in denaturant gradient gels, in clone libraries and by direct sequencing. The sequences originated from an unknown member of the order Oceanospirillales and its 16S rRNA gene fell within a clade of strictly marine invertebrate-associated Gammaproteobacteria. Visual inspection by fluorescent in situ hybridization and transmission electron microscopy indicated a pleomorphic bacterium with no visible cell wall, located in aggregates inside vacuoles scattered within the gill cells cytoplasm. Intracellular Oceanospirillales exist in bathymodiolin mussels (parasites), Osedax worms and whiteflies (symbionts). This bacterium apparently lives in a specific association with the Acesta.
Department of Biology, University of Bergen, Bergen, Norway. sigmund.jensen@bio.uib.no
Sigmund
S
Jensen
Sébastien
S
Duperron
Nils-Kåre
NK
Birkeland
Martin
M
Hovland
D000818:Animals; D049872:Bivalvia / Q000382:microbiology*; D020563:Gammaproteobacteria / Q000145:classification / Q000235:genetics / Q000302:isolation & purification* / Q000648:ultrastructure; D005880:Gills / Q000382:microbiology; D017404:In Situ Hybridization, Fluorescence; D046529:Microscopy, Electron, Transmission; D008969:Molecular Sequence Data; D009664:Norway; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D012407:rRNA Operon
D012336:RNA, Ribosomal, 16S