Browsing Bergen Open Research Archive by Author "Dahle, Håkon"
Now showing items 1-18 of 18
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Adaptive evolution of viruses infecting marine microalgae (haptophytes), from acute infections to stable coexistence
Sandaa, Ruth-Anne; Saltvedt, Marius Rydningen; Dahle, Håkon; Wang, Haina; Våge, Selina; Blanc-Mathieu, Romain; Steen, Ida Helene; Grimsley, Nigel; Edvardsen, Bente; Ogata, Hiroyuki; Lawrence, Janice (Journal article; Peer reviewed, 2022)Collectively known as phytoplankton, photosynthetic microbes form the base of the marine food web, and account for up to half of the primary production on Earth. Haptophytes are key components of this phytoplankton community, ... -
A case study of biofilter activation and microbial nitrification in a marine recirculation aquaculture system for rearing Atlantic salmon (Salmo salar L.)
Roalkvam, Irene; Drønen, Karine; Dahle, Håkon; Wergeland, Heidrun Inger (Peer reviewed; Journal article, 2020-09)Marine recirculation aquaculture system (RAS) is a prominent technology within fish farming. However, the nitrifying bacteria in the biofilter have low growth rates, which can make the biofilter activation a long and ... -
Energy landscapes shape microbial communities in hydrothermal systems on the Arctic Mid-Ocean Ridge
Dahle, Håkon; Økland, Ingeborg Elisabet; Thorseth, Ingunn Hindenes; Pedersen, Rolf B.; Steen, Ida Helene (Peer reviewed; Journal article, 2015-01-09)Methods developed in geochemical modelling combined with recent advances in molecular microbial ecology provide new opportunities to explore how microbial communities are shaped by their chemical surroundings. Here, we ... -
Evolution of temperature optimum in Thermotogaceae and the prediction of trait values of uncultured organisms
Dahle, Håkon; Hannisdal, Bjarte; Steinsbu, Bjørn Olav; Ommedal, Hege; Einen, Jørn; Jensen, Sigmund; Larsen, Øyvind; Øvreås, Lise; Norland, Svein (Peer reviewed; Journal article, 2011-06-03)Quantitative characterization of the mode and rate of phenotypic evolution is rarely applied to prokaryotes. Here, we present an analysis of temperature optimum (Topt) evolution in the thermophilic family Thermotogaceae, ... -
Exploring codon adjustment strategies towards Escherichia coli-based production of viral proteins encoded by HTH1, a novel prophage of the marine bacterium Hypnocyclicus thermotrophus
Arsin, Hasan; Jasilionis, Andrius; Dahle, Håkon; Sandaa, Ruth-Anne; Stokke, Runar; Eva, Nordberg Karlsson; Steen, Ida Helene (Journal article; Peer reviewed, 2021)Marine viral sequence space is immense and presents a promising resource for the discovery of new enzymes interesting for research and biotechnology. However, bottlenecks in the functional annotation of viral genes and ... -
Hot Vents Beneath an Icy Ocean: The Aurora Vent Field, Gakkel Ridge, Revealed
Ramirez-Llodra, Eva; Argentino, Claudio; Baker, Maria; Boetius, Antje; Costa, Carolina; Dahle, Håkon; Denny, Emily Maria; Dessandier, Pierre-Antoine; Eilertsen, Mari Heggernes; Ferré, Benedicte; German, Cristopher R.; Hand, Kevin; Hilário, Ana; Hislop, Lawrence; Jamieson, John W.; Kalenitchenko, Dimitri; Mall, Achim; Panieri, Giuliana; Purser, Autun; Ramalho, Sofia P.; Reeves, Eoghan; Rolley, Leighton; Pereira, Samuel; de Azevedo Ribeiro, Pedro Miguel; Sert, Muhammed Fatih; Steen, Ida Helene; Stetzler, Marie Helene Paula; Stokke, Runar; Victorero, Lissette; Vulcano, Francesca; Vågenes, Stig; Waghorn, Kate Alyse; Bünz, Stefan (Journal article; Peer reviewed, 2022)Evidence of hydrothermal venting on the ultra-slow spreading Gakkel Ridge in the Central Arctic Ocean has been available since 2001, with first visual evidence of black smokers on the Aurora Vent Field obtained in 2014. ... -
Indigenous Ammonia-Oxidizing Archaea in Oxic Subseafloor Oceanic Crust
Zhao, Rui; Dahle, Håkon; Ramírez, Gustavo A.; Jørgensen, Steffen Leth (Journal article, 2020-03-10)Oceanic ridge flank systems represent one of the largest and leastexplored microbial habitats on Earth. Fundamental ecological questions regarding community activity, recruitment, and succession in this environment remain ... -
Microbial colonization and community stability in a marine post-smolt RAS inoculated with a commercial starter culture
Drønen, Asbjørg Karine; Roalkvam, Irene; Dahle, Håkon; Nilsen, Hanne Katrine; Olsen, Anne Berit; Wergeland, Heidrun Inger (Journal article; Peer reviewed, 2021)The performance of a commercial starter culture was investigated in a new marine post-smolt RAS, analyzing the microbial communities of 100 samples collected monthly over a year from biofilter biofilm carriers, tank wall ... -
Microbial Communities in a Flow-Through Fish Farm for Lumpfish (Cyclopterus lumpus L.) During Healthy Rearing Conditions
Roalkvam, Irene; Drønen, Karine; Dahle, Håkon; Wergeland, Heidrun Inger (Peer reviewed; Journal article, 2019-07-12)Lumpfish can efficiently remove sea lice from Atlantic salmon in net-pens, and production of lumpfish in closed fish farms is a new, fast developing industry in Norway. However, periodic outbreaks of bacterial diseases in ... -
The Microbiome and Occurrence of Methanotrophy in Carnivorous Sponges
Hestetun, Jon Thomassen; Dahle, Håkon; Jørgensen, Steffen Leth; Olsen, Bernt Rydland; Rapp, Hans Tore (Peer reviewed; Journal article, 2016-11-09)As shown by recent studies, filter-feeding sponges are known to host a wide variety of microorganisms. However, the microbial community of the non-filtering carnivorous sponges (Porifera, Cladorhizidae) has been the subject ... -
Molecular evidence of parallel evolution in a cyanophage
Tjendra, Jesslyn; Storesund, Julia Endresen; Dahle, Håkon; Sandaa, Ruth-Anne; Våge, Selina (Journal article; Peer reviewed, 2023)Antagonistic interactions between bacteriophage (phage) and its bacterial host drives the continual selection for resistance and counter-defence. To date, much remains unknown about the genomic evolution that occurs as ... -
On how the power supply shapes microbial survival
Diego Castro, David; Hannisdal, Bjarte; Dahle, Håkon (Journal article; Peer reviewed, 2021)Understanding how environmental factors affect microbial survival is an important open problem in microbial ecology. Patterns of microbial community structure have been characterized across a wide range of different ... -
Phylogenetic and functional diverse ANME-1 thrive in Arctic hydrothermal vents
Vulcano, Francesca; Hahn, Cedric Jasper; Roerdink, Desiree Lisette; Dahle, Håkon; Reeves, Eoghan; Wegener, Gunter; Steen, Ida Helene; Stokke, Runar (Journal article; Peer reviewed, 2022)The methane-rich areas, the Loki's Castle vent field and the Jan Mayen vent field at the Arctic Mid Ocean Ridge (AMOR), host abundant niches for anaerobic methane-oxidizers, which are predominantly filled by members of the ... -
Presence and habitats of bacterial fish pathogen relatives in a marine salmon post-smolt RAS
Drønen, Asbjørg Karine; Roalkvam, Irene; Nilsen, Hanne Katrine; Olsen, Anne Berit; Dahle, Håkon; Wergeland, Heidrun Inger (Journal article; Peer reviewed, 2022)Recycling aquaculture system (RAS) requires well-functioning microbial communities to support fish welfare and to minimize the risk of spreading diseases. In this study of a marine post-smolt RAS we searched for groups of ... -
Profundibacter amoris gen. nov., sp. nov., a new member of the Roseobacter clade isolated from Loki's Castle Vent Field on the Arctic Mid-Ocean Ridge
Le Moine Bauer, Sven; Sjøberg, Andreas Gilje; L´Haridon, Stephane; Stokke, Runar; Roalkvam, Irene; Steen, Ida Helene; Dahle, Håkon (Peer reviewed; Journal article, 2019)A bacterial strain, designated BAR1T, was isolated from a microbial mat growing on the surface of a barite chimney at the Loki’s Castle Vent Field, at a depth of 2216 m. Cells of strain BAR1T were rod-shaped, Gram-reacti ... -
Putative novel hydrogen- and iron-oxidizing sheath-producing Zetaproteobacteria thrive at the Fåvne deep-sea hydrothermal vent field
Hribovšek, Petra; Denny, Emily Maria; Dahle, Håkon; Mall, Achim; Viflot, Thomas Øfstegaard; Boonnawa, Chanakan; Reeves, Eoghan; Steen, Ida Helene; Stokke, Runar (Journal article; Peer reviewed, 2023)Iron-oxidizing Zetaproteobacteria are well known to colonize deep-sea hydrothermal vent fields around the world where iron-rich fluids are discharged into oxic seawater. How inter-field and intra-field differences in ... -
Sedimentary ancient DNA sequences reveal marine ecosystem shifts and indicator taxa for glacial-interglacial sea ice conditions
Grant, Danielle; Steinsland, Kristine; Cordier, Tristan; Ninnemann, Ulysses S; Ijaz, Umer Zeeshan; Dahle, Håkon; De Schepper, Stijn; Ray, Jessica Louise (Journal article; Peer reviewed, 2024)Sedimentary ancient DNA (sedaDNA) analysis is a promising new approach for reconstructing the impact of past climate and environmental changes on marine paleobiodiversity. By recovering, amplifying, and sequencing taxonomically ... -
Tailoring Hydrothermal Vent Biodiversity Toward Improved Biodiscovery Using a Novel in situ Enrichment Strategy
Stokke, Runar; Reeves, Eoghan; Dahle, Håkon; Fedøy, Anita-Elin; Viflot, Thomas Øfstegaard; Onstad, Solveig L.; Vulcano, Francesca; Pedersen, Rolf Birger; Eijsink, Vincent; Steen, Ida Helene (Journal article; Peer reviewed, 2020)Deep-sea hydrothermal vents are amongst the most extreme environments on Earth and represent interesting targets for marine bioprospecting and biodiscovery. The microbial communities in hydrothermal vents are often dominated ...