• AgNO3 Sterilizes Grains of Barley (Hordeum vulgare) without Inhibiting Germination—A Necessary Tool for Plant–Microbiome Research 

      Munkager, Victoria; Vestergård, Mette; Primé, Anders; Altenburger, Andreas; de Visser, Eva; Johansen, Jesper Liengaard; Ekelund, Flemming (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-03-17)
      To understand and manipulate the interactions between plants and microorganisms, sterile seeds are a necessity. The seed microbiome (inside and surface microorganisms) is unknown for most plant species and seed-borne microorganisms can persist and transfer to the seedling and rhizosphere, thereby obscuring the effects that purposely introduced microorganisms have on plants. This necessitates that ...
    • Dimorphism in cryptophytes—The case of Teleaulax amphioxeia/Plagioselmis prolonga and its ecological implications 

      Altenburger, Andreas; Blossom, Hannah E.; Garcia-Cuetos, Lydia; Jakobsen, Hans H.; Carstensen, Jacob; Lundholm, Nina; Hansen, Per Juel; Haraguchi, Lumi (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-09-11)
      Growing evidence suggests that sexual reproduction might be common in unicellular organisms, but observations are sparse. Limited knowledge of sexual reproduction constrains understanding of protist ecology. Although <i>Teleaulax amphioxeia</i> and <i>Plagioselmis prolonga</i> are common marine cryptophytes worldwide, and are also important plastid donors for some kleptoplastic ciliates and ...
    • Ecophysiological traits of mixotrophic Strombidium spp 

      Maselli, Maira; Altenburger, Andreas; Stoecker, Diane K.; Hansen, Per Juel (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-09-07)
      Ciliates represent an important trophic link between nanoplankton and mesoplankton. Many species acquire functional chloroplasts from photosynthetic prey, being thus mixotrophs. Little is known about which algae they exploit, and of the relevance of inorganic carbon assimilation to their metabolism. To get insights into these aspects, laboratory cultures of three mixotrophic <i>Strombidium</i> spp. ...
    • First Evidence of the Toxin Domoic Acid in Antarctic Diatom Species 

      Olesen, Anna J.; Altenburger, Andreas; Beszteri, Bank (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-01-26)
      The Southern Ocean is one of the most productive ecosystems in the world. It is an area heavily dependent on marine primary production and serving as a feeding ground for numerous seabirds and marine mammals. Therefore, the phytoplankton composition and presence of toxic species are of crucial importance. Fifteen monoclonal strains of Pseudo-nitzschia subcurvata, a diatom species endemic to the ...
    • Limits to the cellular control of sequestered cryptophyte prey in the marine ciliate Mesodinium rubrum 

      Altenburger, Andreas; Cai, Huimin; Li, Qiye; Drumm, Kirstine; Kim, Miran; Zhu, Yuanzhen; Garcia-Cuetos, Lydia; Zhan, Xiaoyu; Hansen, Per Juel; John, Uwe; Li, Shuaicheng; Lundholm, Nina (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-11-23)
      The marine ciliate <i>Mesodinium rubrum</i> is famous for its ability to acquire and exploit chloroplasts and other cell organelles from some cryptophyte algal species. We sequenced genomes and transcriptomes of free-swimming <i>Teleaulax amphioxeia</i>, as well as well-fed and starved <i>M. rubrum</i> in order to understand cellular processes upon sequestration under different prey and light ...
    • Physiological Responses of Mesodiniummajor to Irradiance, Prey Concentration and Prey Starvation 

      Drumm, Kristine; Norlin, Andreas; Kim, Miran; Altenburger, Andreas; Hansen, Per Juel (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-04-18)
      Ciliates within the <i>Mesodinium rubrum/Mesodinium major</i> species complex harbor chloroplasts and other cell organelles from specific cryptophyte species. <i>Mesodinium major</i> was recently described, and new studies indicate that blooms of <i>M. major</i> are just as common as blooms of <i>M. rubrum</i>. Despite this, the physiology of <i>M. major</i> has never been studied and compared to ...
    • Soil microorganisms decrease barley biomass uniformly across contrasting nitrogen availability 

      Munkager, Victoria; Altenburger, Andreas; Priemé, Anders; Bang-Andreasen, Toke; Rønn, Regin; Vestergård, Mette; Ekelund, Flemming (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-03-30)
      <i>Aims</i> - Microorganisms play a dichotomous role in the soil nitrogen cycle through mineralization and immobilization. We aimed to understand how nitrogen availability modifies the effect of microorganisms on plant growth. We hypothesized that soil microorganisms would increase plant biomass following amendment with a substrate rich in organic nitrogen (net mineralization), be neutral when adding ...