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Vliv potravní preference všenek (Phthiraptera: Amblycera) na formování jejich mikrobiomů
ŽIŽKOVÁ, Kateřina
Microbiome diversity of chewing lice belongs to generaly unexplored topics. This thesis provides the first insight into the microbiomes of 15 chewing lice species of the genus Menacanthus. We detected the presence of two dominant symbiotic bacteria, which occurred in almost all species. We also compared the microbiome diversity of lice with different diet preferences (blood feeding and feather feeding species). Based on these analyses, we identified the main determinants shaping the microbiomes of Menacanthus lice. The microbiomes are namely affected by Menacanthus species identity, its geographical origin, dietary niche, and the extent of the host spectrum that the lice parasitize.
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Biotic, abiotic and symbiotic factors that influence a host-parasitoid food web
BROWN, Joel James
The aim of this thesis was to investigate the deterministic patterns of insect-associated microbiome community composition and to investigate the role of symbiotic bacteria in insect model systems. I have shown that life stage is a key factor influencing microbiome composition, in both holometabolous and hemimetabolous insects, in addition to host species identity and local environment. I was able to find these deterministic patterns by controlling for diet in field studies of microbiomes, which is a well-known influential factor of microbiome communities. My thesis emphasises the importance of investigating the taxonomic and functional diversity of insect microbiomes and including symbiotic microbes in community level studies.
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Transgenerational effects of plant biotic interactions
PUY GUTIÉRREZ, Javier
This thesis focuses on the transgenerational effects triggered by plant biotic interactions and explores their relevance on ecological and evolutionary processes. The following sections document novel results that show their important consequences on different aspects. Primarily, we established the necessary methodology to be able to explore these questions and to disentangle the mechanisms originating the transgenerational plasticity by validating a demethylation method. Then, we checked whether the biotic interactions alter the phenotype via within-generation and transgenerational plasticity, examining the magnitude and direction of the response on each specific "response traits". Lastly, the potential role of transgenerational plasticity for adaptation, species coexistence, creating biodiversity and population and ecosystem functioning is tested.
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Mutual development of the Bratislava, the Danube river and the floodplain forests
Falathová, Katarína
The floodplain forest, natural environment of the Danube, is protected area located along the main flow of the river near Bratislava. The question of protection and coexistence of these areas is very important today due to the growth of the city. The regulation of the Danube in the past predetermined the development of the city and set aside territories that are protected. The initiative to restore forgotten branches of Danube is current. The question is, what is the future of this symbiosis of the Danube, floodplain forest and Bratislava, and what are the possibilities of their mutual development? The aim of the research is to contribute to the topic by comparing landscape changes from 1990 to 2018 using CORINE Land Cover (CLC) and to design the possible future direction in research of the Danube and floodplain forests in contact with the southern part of Bratislava.
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Comparative methods for studying adaptive traits of fungal symbionts
Veselská, Tereza ; Kolařík, Miroslav (advisor) ; Voigt, Kerstin (referee) ; Dvořák, Miloň (referee)
The kingdom Fungi encompasses an estimated 2.2 to 6.2 million species that occupy diverse environments, including aquatic, extremely dry, and hot or frosty habitats all over the world. To cope with adverse environmental conditions, fungi have developed numerous adaptations and life strategies, including symbiosis with other organisms, ranging from close, reciprocally beneficial (mutualistic) associations to severe pathogenic infestations. These interactions have an enormous impact on ecosystem functioning, with implications for agriculture and human health. For this reason, understanding the mechanisms enabling the successful development of fungal interactions is necessary for their efficient management. Recent advances in different 'omics' approaches have enabled us to compare species responses to the environment in a more complex way than before and to gain deeper insights into the adaptive mechanisms underlying specific life strategies. My thesis is divided into four main sections. In the first section, I sum up findings about adaptations of fungal symbionts of plants and animals. Then, I introduce two fungal genera, Geosmithia and Pseudogymnoascus, to which I applied comparative methods for tracking adaptive traits. The ecological diversity of the genus Geosmithia allows to trace adaptive...
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Photobiont dynamics of Stereocaulon lichens
Vančurová, Lucie ; Škaloud, Pavel (advisor) ; Bérešová, Anna (referee) ; Dal Grande, Francesco (referee)
7 Abstract Lichens are an iconic example of symbiosis. They are widespread throughout the world. In some ecosystems, lichens are dominant autotrophs, sometimes one of the few living organisms capable of surviving local conditions. They grow on a variety of substrata, including artificial surfaces. Great diversity of their life strategies is related to the diversity of symbiotic partners forming the lichen thalli, which remains largely unresearched. Lichens as sessile organisms often have to face a changing environment or adapt to conditions at new localities where their propagules can spread. We have chosen the widespread genus Stereocaulon as a model system for studying symbiotic relationships in lichens and the connection of this relationships with environmental conditions. The main goals of this thesis were (1) to uncover the diversity of phycobionts (i.e., green algal photobionts) associated with Stereocaulon within the whole genus and particular species-level lineages; (2) to identify environmental factors affecting the distribution of phycobionts and their relationships with mycobionts on a global and local scale; and (3) to inspect the possibility of sharing phycobiont pool with other lichens and soil. For this purpose, we used phylogenetic analyses (ITS rDNA, 18S rDNA, rbcL, and actin type I gene),...
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The role of trehalose in mycorrhizal associations
Šoch, Jan ; Ponert, Jan (advisor) ; Hála, Michal (referee)
Mycorrhizal symbiosis is a widely spread phenomenon in nature. A translocation of nutrients occurs between symbionts with disaccharide trehalose playing a key role in the process. However, this saccharide fulfils many important roles in metabolism of fungi and plants. Fungi use trehalose mainly as storage and transport saccharide. On the other hand, trehalose occurs in extremely low amounts in plants where it acts as a signal molecule. Thus it is likely that the saccharide could be used by the fungus to manipulate plant metabolism on a physical interface between symbionts. Trehalose has a similar function in many parasitic interactions. In most cases of mycorrhizal associations trehalose synthesis creates a carbon sink in mycelium which leads to saccharide transfer from the host plant to the fungus. Completely different situation occurs in the types of mycorrhizal symbiosis, where saccharides are translocated from a fungus to a plant. Some plants can utilize trehalose effectively as a sole source of energy. Consequently, the question raises - could such plants gain fungal trehalose on purpose as a source of energy and carbon? This review aims to assess and discuss the mentioned possibilities considering available literature. Key words: mycorrhiza, orchids, parazitism, saccharides, sink, symbiosis,...
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Symbiosis as a model for a new biology
Lhotský, Josef ; Markoš, Anton (advisor) ; Černý, Robert (referee)
Contemporary biology belongs among the most diversified sciences; yet one of its most fundamental and controversial questions is surprisingly: "What is life?". The aim of this study is to point out that biology is special among other natural sciences because its need of the notion of meaning. Meaning takes the central position in the biological rea-soning. Compared to other sciences, biology has to reflect the dimension of information and its interpretation: language-like properties, communication and interpretation belong to the basic characteristics of life. In spite of the fact, most contemporary theories of evo-lution deny active participation of living beings on the very process - living being come out of its description as puppets or zombies controlled by external forces. As a remedy from such a situation, biology should start with a new model for living entities. A bene-ficial methapor seems to be that of natural languages, i.e. an analogy between a net of historical interactions and conventional ways of interpretation of meaning in (i) living entities and (ii) in system of natural languages. I consider as the most appropriate biolo-gical systems for modeling of such a network of symbiotic interactions, i. e. the pheno-menon of symbiosis and especially symbiogenesis. Keywords: life,...
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Specific features of streptomycetes isolated from human tissues
Kodatová, Anežka ; Petříčková, Kateřina (advisor) ; Zikánová, Blanka (referee)
This bachelor thesis focuses on activities of the bacterial genus Streptomyces in relations to plants, animals and human. Many cases of their symbiotic relationships with plants are known, but there is also a common plant pathogen S. scabies. As a primary soil bacteria, their association with animals is infrequent, but not exceptional. Symbiotic relationships have been observed for example in several insect species. Streptomyces have been repeatedly isolated from the human microbiome, however only a little information about their influence on human body is available. Due to the wide production of secondary metabolites affecting other microorganisms, their role can be assumed as significant. The relationship between human Streptomyces and human could have a parallel in the Streptomyces symbiosis with plants and insects, but it can also have certain effects on pathogenesis. The ability of beta haemolysis was demonstrated in tested strains. In addition, there are cases of serious diseases caused by Streptomyces. Next to the relatively common actinomycosis in the regions of Sudan and India, diseases such as pneumonia or abscess were reported.
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Prokaryotic symbionts of free-living anaerobic protists
Poláková, Kateřina ; Čepička, Ivan (advisor) ; Hampl, Vladimír (referee)
Anaerobní prvoci jsou organismy obývající ředí bez přítomnosti kyslíku. Najdeme je anoxických habitatech jako jsou mořské a sladkovodní sedimenty, komunální skládky, nesmíme opomenout zástupce žijící v bachoru přežvýkavců, trávicím traktu švábů a dalších živočichů. Většinou mají anaerobní deriváty mitochondrií, často hydrogenosomy, organely produkující vodík. Metabolismus anaerobních prvoků je ve srovnání s aerobními organismy méně efektivní Časté interakce anaerobních ický my však mohou Symbiózy mezi anaerobními běžné a vznikly u zástupců mnoha anaerobních linií. žít buď endosymbioticky, uvnitř buňky hostitele, nebo ektosymbioticky, na povrchu hostitelské buňky. Dvě ekologicky významné skupiny prokaryot si dokázaly osvojit život symbiotickém vztahu volně žijícími anaerobními prvoky anogenní archebakterie, osídlující hlavně , využívají vodík nické sloučeniny k anu a síran redukující bakterie, žijící hlavně na povrchu buněk, využívají vodík a různé organické sloučeniny k redukci síranu na sulfan. Velmi málo se ví o bližším charakteru těchto vztahů druhové identitě a hostitelské specifitě prokaryotických symbiontů. Další výzkum je nutný pro pochopení fenoménu symbióz v anoxickém světě. Klíčová slova: anaerobní prvoci symbióza anogenní archebakterie síran redukující bakterie
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