• Co-cultivation and transcriptome sequencing of two co-existing fish pathogens Moritella viscosa and Aliivibrio wodanis 

      Hjerde, Erik; Karlsen, Christian; Sørum, Henning; Parkhill, Julian; Willassen, Nils Peder; Thomson, Nicholas R. (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-06-10)
      Background: Aliivibrio wodanis and Moritella viscosa have often been isolated concurrently from fish with winterulcer disease. Little is known about the interaction between the two bacterial species and how the presence of one bacterial species affects the behaviour of the other. Results: The impact on bacterial growth in co-culture was investigated in vitro, and the presence of A. wodanis has an ...
    • Complete genome sequence of Halomonas sp. R5-57 

      Williamson, Adele Kim; De Santi, Concetta; Altermark, Bjørn; Karlsen, Christian; Hjerde, Erik (Journal article; Tidsskriftartikkel; Peer reviewed, 2016)
      The marine Arctic isolate Halomonas sp. R5-57 was sequenced as part of a bioprospecting project which aims to discover novel enzymes and organisms from low-temperature environments, with potential uses in biotechnological applications. Phenotypically, Halomonas sp. R5-57 exhibits high salt tolerance over a wide range of temperatures and has extra-cellular hydrolytic activities with several ...
    • Identification and cloning of immunogenic Aliivibrio salmonicida Pal-like protein present in profiled outer membrane and secreted subproteome 

      Karlsen, Christian; Espelid, sigrun; Willassen, Nils P; Paulsen, steinar (Journal article; Tidsskriftartikkel; Peer reviewed, 2011)
      Aliivibrio salmonicida is the aetiological agent of cold water vibriosis affecting farmed fish species, a disease that today is fully controlled by vaccination. However, the molecular mechanisms behind the successful vaccine are largely unknown. In order to gain insight into the possible mechanisms of A. salmonicida vaccines, we report here the profiles of both the outer membrane and secreted ...
    • Pan genome and CRISPR analyses of the bacterial fish pathogen Moritella viscosa 

      Karlsen, Christian; Hjerde, Erik; Klemetsen, Terje; Willassen, Nils Peder (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-04-20)
      Background: Winter-ulcer Moritella viscosa infections continue to be a significant burden in Atlantic salmon (Salmo salar L.) farming. M. viscosa comprises two main clusters that differ in genetic variation and phenotypes including virulence. Horizontal gene transfer through acquisition and loss of mobile genetic elements (MGEs) is a major driving force of bacterial diversification. To gain insight ...
    • Presence of acyl-homoserine lactones in 57 members of the Vibrionaceae family 

      Purohit, Amit Anand; Johansen, Jostein a; Hansen, Hilde; Leiros, Hanna-Kirsti S.; Kashulin, Alexander; Karlsen, Christian; Smalås, Arne O.; Haugen, Peik; Willassen, Nils Peder (Journal article; Tidsskriftartikkel; Peer reviewed, 2013-05-31)
      Aims: The aim of this study was to use a sensitive method to screen and quantify 57 Vibrionaceae strains for the production of acyl-homoserine lactones (AHLs) and map the resulting AHL profiles onto a host phylogeny.<p> <p>Methods and Results: We used a high-performance liquid chromatography– tandem mass spectrometry (HPLC-MS/MS) protocol to measure AHLs in spent media after bacterial growth. ...