Sökning: "symbiont"
Visar resultat 6 - 10 av 22 avhandlingar innehållade ordet symbiont.
6. Significance of N2 fixing planktonic symbioses for open ocean ecosystems
Sammanfattning : Di-nitrogen (N2) fixers, also called diazotrophs, are able to reduce atmospheric N2 into bioavailable nitrogen, giving them an advantage in open ocean regions with low dissolved inorganic nitrogen concentrations. The focus of this thesis are three lineages of symbiotic heterocystous filamentous types (het-1, het-2 and het-3), that associate with several genera of microalgae called diatoms (collectively referred to as Diatom Diazotroph Associations, DDAs). LÄS MER
7. In silico Studies of Early Eukaryotic Evolution
Sammanfattning : A question of great interest in evolutionary biology is how and why the eukaryotic cell evolved. Several hypotheses have been proposed, ranging from an early emergence of a primitive eukaryotic cell, to various fusion models like the hydrogen hypothesis. Within this context, relevant bacterial gene families and genomes are examined in this thesis. LÄS MER
8. Novel Modes of Immune Activation in Anopheles gambiae and Drosophila melanogaster
Sammanfattning : Malaria is a disease of poverty and continues to plague a great part of the world’s population. An increased understanding of the interactions between the vector mosquito, the malaria parasite, and also the mosquito gut microbiota are pivotal for the development of novel measures against the disease. LÄS MER
9. Cyanobacterial genome evolution subsequent to domestication by a plant (Azolla)
Sammanfattning : Cyanobacteria are an ancient and globally distributed group of photosynthetic prokaryotes including species capable of fixing atmospheric dinitrogen (N2) into biologically available ammonia via the enzyme complex nitrogenase. The ability to form symbiotic interactions with eukaryotic hosts is a notable feature of cyanobacteria and one which, via an ancient endosymbiotic event, led to the evolution of chloroplasts and eventually to the plant dominated biosphere of the globe. LÄS MER
10. Genomic and morphological diversity of marine planktonic diatom-diazotroph associations : a continuum of integration and diversification through geological time
Sammanfattning : Symbioses between eukaryotes and nitrogen (N2)-fixing cyanobacteria (or diazotrophs) are quite common in the plankton community. A few genera of diatoms (Bacillariophyceae) such as Rhizosolenia, Hemiaulus and Chaetoceros are well known to form symbioses with the heterocystous diazotrophic cyanobacteria Richelia intracellularis and Calothrix rhizosoleniae. LÄS MER
