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Diversity of ciliates of the family Nyctotheridae in cockroaches
Soviš, Matyáš ; Čepička, Ivan (advisor) ; Škaloud, Pavel (referee)
Cockroaches are tremendously interesting group of insects with broad morphological diversity and a wide range of lifestyles. They are known to host a plethora of fascinating protists ranging from excavate flagellates through gregarines and amoebozoans to extraordinary ciliates of the group Armophorea. There is however, in contrast to the flagellates, only scarce information on these intestinal ciliates. The available data are mostly only morphological and there is a limited information on their host specificity. Therefore, we chose to inspect the diversity of ciliates in cockroaches, both in the stock cultures of Department of Zoology on Charles University as well as in those collected in nature. We studied their presence in various cockroach lineages, obtained 18S rRNA gene sequence data, and assessed their phylogenetic relationships. We also performed protargol staining of the cells to characterize the morphology of individual lineages.
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The phenomenon of symbiosis and its importance to theoretical biology
Lhotský, Josef
7 Abstract Close physical interspecific associations called symbioses are central for understanding both evolution and interactions of all branches of living creatures, as well as shaping the Earth's physical features - in other words, they are essential for understanding the nature of whole biosphere. Symbiotic research takes place in some variation in all fields of biology, and since the nature of the phenomenon apparently has a fundamental importance as an exceptional underlying & unifying scheme, there is growing need for appropriate theoretical analysis. Here I discuss the theoretical frame, definition and history of the concept of symbiotic interactions and its significance and use in theoretical biology. Keywords: symbiosis, life, microorganisms, evolution, metaphors and models
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The role of microbial symbionts in the life cycle of Ips typographus
Havlíček, Václav ; Kolařík, Miroslav (advisor) ; Veselská, Tereza (referee)
Bark beetles (Coleoptera;Scolytinae) are usually considered as pests, because they attack trees in the protected and recreational forests and in the forests with economic importance. Their larvae develop under the bark, where it disturb the conductive tissues and affect the nutrient transport. Ips typographus attack Norway spruce (Picea abies). P. abies is an economic important woody plant. The life cycle of bark beetle is affected by its microbial symbionts in both positive and negative manner. Most of these organisms are facultative symbionts and they aren't completely depend on bark beetles. However, bark beetles are completely depend on its microbial symbionts. Symbiotic bacteria and fungus can be disseminated without bark beetles, but they are often spread by beetles. Microbial symbionts help overcome the defence mechanism of attacked trees, later they help with food digestion. Some fungi species can accumulate nitrogen in areas near the feeding chambers and improve ratio between carbon and nitrogen in plant tissue. Some bacteria are able to fix atmospheric nitrogen or use uric acid, helping with nitrogen recycling. Number of intestinal symbiont diversity increase in the course of host development. This symbionts are probably gained during feeding. The presence and prevalence of the...
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Diversity of symbiotic partners within the lichen family Verrucariaceae
Schmidtová, Jana ; Škaloud, Pavel (advisor) ; Steinová, Jana (referee)
This thesis summarizes the current knowledge of photobionts of the lichen family Verrucariaceae. It classifies the free-living photobionts systematically, mentions their main morphological features, distribution, and ecology, and notices their participation in the symbiosis. Subsequently, it also describes and characterizes the fungal component of mycobionts, their phylogenetic position, the main morphological features, distribution, and the most common habitats. Finally, it studies the influence of the environment, mycobiont, and other factors in the occurrence of particular photobionts in lichens. Keywords: Verrucariaceae, photobiont, mycobiont, lichen, diversity, symbiosis, characterization
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Symbiotic bacteria of the genus Wolbachia in sand flies and mosquitoes.
Rehbergerová, Markéta ; Dvořák, Vít (advisor) ; Jančářová, Magdaléna (referee)
Bacteria of the genus Wolbachia (Proteobacteria, Rickettsiales, Rickettsiaceae) are maternally inherited intracellular symbionts of many species of arthropods (Arthropoda) and filarial nematodes (Nematoda, Secernentea). Due to the ability of Wolbachia to induce reproductive anomalies in their hosts and to reduce their infection by pathogenic organisms and viruses, they are profoundly studied. This bachelor thesis is a summary of available information regarding interactions of Wolbachia with mosquitoes (Diptera, Culicidae) and sand flies (Diptera, Psychodidae, Phlebotominae), vectors of many important infectious pathogens, and possibilities of their use in the control of pathogen transmission. Key words: Wolbachia, Phlebotominae, Culicidae, vector-borne diseases, symbiosis, vector control method
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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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Evoluce genomu bakteriálních symbiontů vši \kur{Polyplax serrata} (Phthiraptera, Anoplura)
ŘÍHOVÁ, Jana
Blood-sucking louse Polyplax serrata harbor two phylogenetically distinct symbiotic bacteria from the orders Legionellales (Gammaproteobacteria) and Neisseriales (Betaproteobacteria). Based on rigorous phylogenetic analyses, the first bacteria was confirmed as member of genus Legionella, and the name Candidatus Legionella polyplacis, sp. n. was proposed. Vertical transgeneration transmission was proved by visualisation of the symbiont in host tissues. Improved genome of latter symbiont is considerably larger and possesses more metabolic functions. In the genome, I found horizontally transferred operon, which encode synthesis of enzymes involved in urea cleavage.
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Dynamics of a lichen symbiosis
Vaiglová, Zuzana ; Škaloud, Pavel (advisor) ; Vondrák, Jan (referee)
The symbiotic relationships often represent not only the permanent cohabitation of two organisms, but they can evolve and change over time. Many papers published so far focused on the the specificity of lichens, characterising both highly specific species and those that can establish a symbiosis with many algal genotypes. In this second case we can imagine the possibility of a photobiont exchange during the life of lichen - the dynamics of lichen symbiosis. In this thesis I compared the occurence and diversity of photobionts within the thalli of lichens growing on the disturbed localities and on the the localities without the disturbance. These two types of localities were similar to species richness of photobionts, but the disturbed localities dominated by the number of photobiont genera. These localities also reached a higher value of phylogenetic diversity. Conversely, non-phylogenetic analysis revealed the higher level of photobiont diversity on non-disturbed localities, where the core of diversity was formed by different lineages of Trebouxia. I have also found the lichens, which cooperate with different algae on disturbed and non-disturbed localities. The photobiont distribution presented in this paper shows the possibility of photobiont exchange during the community succesion. The...
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Utilization of cellulose and hemicellulose as a source of energy by symbiotic protists and other organisms
Hammerbauerová, Iva ; Tachezy, Jan (advisor) ; Hrdý, Ivan (referee)
In this thesis I focus on the enzymatic degradation of plant structural polysaccharides cellulose and hemicellulose. I describe the enzymes involved in their lysis and their breakdown and their function and occurence among organisms. I also pay attention to the mechanisms of xylose and arabinose catabolism as pentoses found in hemicellulose. I describe some niches where cellulose and hemicellulose degradation takes place and organisms that take part in it. Finally I shortly point out the biotechnological importance of these organisms in the production of bioethanol.
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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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