Presence and activity of anaerobic ammonium-oxidizing bacteria at deep-sea hydrothermal vents.
Recent studies indicate that ammonia is an important electron donor for the oxidation of fixed nitrogen, both in the marine water column and sediments. This process, known as anammox, has so far only been observed in a large range of temperature habitats. The present study investigated the role of anammox in hydrothermal settings. During three oceanographic expeditions to the Mid-Atlantic Ridge, hydrothermal samples were collected from five vent sites, at depths ranging from 750 to 3650 m from cold to hot habitats. Evidence for the occurrence of anammox in these particular habitats was demonstrated by concurrent surveys, including the amplification of 16S rRNA gene sequences related to known anammox bacteria, ladderanes lipids analysis and measurement of a (14)N(15)N dinitrogen production in isotope-pairing experiments at 60 and 85 degrees C. Together these results indicate that new deep-branching anammox bacteria may be active in these hot habitats.
Byrne
Nathalie
N
Laboratoire de Microbiologie des Environnements Extrêmes UMR6197 IFREMER, Centre de Brest-BP70/IUEM, Plouzane, France. nathalie.byrne@univ-brest.fr
Strous
Marc
M
Crépeau
Valentin
V
Kartal
Boran
B
Birrien
Jean-Louis
JL
Schmid
Markus
M
Lesongeur
Françoise
F
Schouten
Stefan
S
Jaeschke
Andrea
A
Jetten
Mike
M
Prieur
Daniel
D
Godfroy
Anne
A
D001267:Atlantic Ocean; D001421:Bacteria, Anaerobic / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D020459:Genes, rRNA; D045482:Hot Springs / Q000382:microbiology*; D008055:Lipids / Q000032:analysis; D008873:Mid-Atlantic Region; D008969:Molecular Sequence Data; D009584:Nitrogen / Q000378:metabolism; D010084:Oxidation-Reduction; D010802:Phylogeny; D000644:Quaternary Ammonium Compounds / Q000378:metabolism*; D012329:RNA, Bacterial / Q000235:genetics; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012623:Seawater / Q000382:microbiology*; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid
D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D008055:Lipids; D000644:Quaternary Ammonium Compounds; D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S; D009584:Nitrogen