title: NC10 bacteria in marine oxygen minimum zones.
abstract: Bacteria of the NC10 phylum link anaerobic methane oxidation to nitrite denitrification through a unique O2-producing intra-aerobic methanotrophy pathway. A niche for NC10 in the pelagic ocean has not been confirmed. We show that NC10 bacteria are present and transcriptionally active in oceanic oxygen minimum zones (OMZs) off northern Mexico and Costa Rica. NC10 16S rRNA genes were detected at all sites, peaking in abundance in the anoxic zone with elevated nitrite and methane concentrations. Phylogenetic analysis of particulate methane monooxygenase genes further confirmed the presence of NC10. rRNA and mRNA transcripts assignable to NC10 peaked within the OMZ and included genes of the putative nitrite-dependent intra-aerobic pathway, with high representation of transcripts containing the unique motif structure of the nitric oxide (NO) reductase of NC10 bacteria, hypothesized to participate in O2-producing NO dismutation. These findings confirm pelagic OMZs as a niche for NC10, suggesting a role for this group in OMZ nitrogen, methane and oxygen cycling.
authors.affiliation: School of Biology, Georgia Institute of Technology, Atlanta, GA, USA.
authors.forename: Cory C
authors.initials: CC
authors.lastname: Padilla
authors.affiliation: Department of Biology and Nordic Center for Earth Evolution (NordCEE), University of Southern Denmark, Odense, Denmark.
authors.forename: Laura A
authors.initials: LA
authors.lastname: Bristow
authors.affiliation: School of Biology, Georgia Institute of Technology, Atlanta, GA, USA.|Biological Laboratories, Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA.
authors.forename: Neha
authors.initials: N
authors.lastname: Sarode
authors.affiliation: Department of Bioscience, Aarhus University, Aarhus, Denmark.
authors.forename: Emilio
authors.initials: E
authors.lastname: Garcia-Robledo
authors.affiliation: Centro de Investigacion en Ciencias del Mar y Limnologia (CIMAR), Universidad de Costa Rica, San Pedro de Montes de Oca, Costa Rica.
authors.forename: Eddy
authors.initials: E
authors.lastname: Gómez Ramírez
authors.affiliation: Department of Molecular Biology and Biochemistry, Middlebury College, Middlebury, VT, USA.
authors.forename: Catherine R
authors.initials: CR
authors.lastname: Benson
authors.affiliation: School for Marine Science and Technology, University of Massachusetts Dartmouth, New Bedford, MA, USA.
authors.forename: Annie
authors.initials: A
authors.lastname: Bourbonnais
authors.affiliation: School for Marine Science and Technology, University of Massachusetts Dartmouth, New Bedford, MA, USA.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Altabet
authors.affiliation: Biological Laboratories, Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA.
authors.forename: Peter R
authors.initials: PR
authors.lastname: Girguis
authors.affiliation: Department of Biology and Nordic Center for Earth Evolution (NordCEE), University of Southern Denmark, Odense, Denmark.
authors.forename: Bo
authors.initials: B
authors.lastname: Thamdrup
authors.affiliation: School of Biology, Georgia Institute of Technology, Atlanta, GA, USA.
authors.forename: Frank J
authors.initials: FJ
authors.lastname: Stewart
mesh_terms: D001419:Bacteria / Q000145:classification* / Q000201:enzymology / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics; D003364:Costa Rica; D058440:Denitrification; D008697:Methane / Q000032:analysis / Q000378:metabolism; D008800:Mexico; D009573:Nitrites / Q000032:analysis / Q000378:metabolism; D009584:Nitrogen / Q000378:metabolism; D009792:Oceans and Seas; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000235:genetics; D010100:Oxygen / Q000378:metabolism*; D010105:Oxygenases / Q000235:genetics; D010802:Phylogeny
chemical_list: D001426:Bacterial Proteins; D009573:Nitrites; D010088:Oxidoreductases; D010105:Oxygenases; C021555:methane monooxygenase; C034747:nitric-oxide reductase; D009584:Nitrogen; D008697:Methane; D010100:Oxygen