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Interactions among free-living prokaryotes and protists in microbial communities
Jirouchová, Kateřina ; Pánek, Tomáš (advisor) ; Fiala, Ivan (referee)
Protists and prokaryotes live in the natural environment in complex microbial communities whose members interact with each other. These communities consist of a few to many species that interact with each other in many ways such as predation/prey, ecto/endosymbiosis, parasitism, modulation of development or behaviour and harmful algicidal/bactericidal interactions, resulting in a complex network of interactions that influence structure of the microbial community as well as metabolism and behaviour of present species. This bachelor thesis is an overview of the interactions between free-living protists and prokaryotes within microbial communities, excluding well-studied interactions such as predation, parasitism, and ecto/endosymbiosis, while focusing on the diversity of lesser- known interactions, highlighting their importance and future research opportunities.
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Diversity and evolution of anaerobic Heterolobosea
Pánek, Tomáš ; Čepička, Ivan (advisor) ; Oborník, Miroslav (referee) ; Vávra, Jiří (referee)
9 ABSTRACT This thesis is focused on the phylogeny, diversity, and cell structure of obligately anaerobic Heterolobosea (Excavata: Discoba). Using culture-based approach, we have discovered their hidden species diversity and described 11 new species. Our phylogenetic analyses showed that obligately anaerobic heteroloboseans evolved at least twice independently (Creneidae and Psalteriomonadidae). Psalteriomonadidae is a major anaerobic lineage of Heterolobosea as it includes 16 species and 5 genera. Most psalteriomonadids have acristate mitochondria, although Pseudoharpagon pertyi probably possesses remnants of mitochondrial cristae. Creneidae are represented just by a single species, Creneis carolina, which displays unique cell structure and life cycle. Architecture of its flagellar apparatus is not readily comparable with any other eukaryotes and at least some cytoskeletal elements have undergone unprecedented evolutionary positional changes. Anaerobic heteroloboseans are just rarely detected by environmental, culture-independent approaches. Thus, it is impossible to estimate their real species diversity. Nevertheless, our current data on anaerobic jakobids, another lineage of Discoba, indicates that the culture-based approach is relatively powerful to discover species diversity of anaerobic excavates. In...
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Late Cenozoic response of the selected fluvial systems of the Bohemian Massif to tectonics.
Flašar, Jan ; Martínek, Karel (advisor) ; Pánek, Tomáš (referee) ; Moreiras, Stella Maris (referee)
Despite its intraplate tectonic setting, the Bohemian Massif underwent relatively intense tectonic activity during the Cenozoic. This activity has significantly formed the terrain morphology and river geometry, which can easily be observed from the present status of the streams and relief. Although the effect of tectonics and climate on the terrain morphology has been already researched in previous studies, the effect on the geometry of the river systems has not been surveyed complexly. The author's previous master thesis found two remarkable areas within the Bohemian Massif, where the effect of climate and tectonics on the river system geometry and its changes is very probable - the area of western Bohemia along the Mariánské Lázně Fault and the area of the Novohradské hory Mountains and their foothills. The focus of this thesis is to study the mutual interactions between the tectonic activity and the geometry of selected river systems in the Bohemian Massif. The goal is not only to prove the connection but also to test and evaluate the set of methods that can be useful for localizing those places with recent tectonic activity and which can be applied in similar areas in the future. Both areas - along the Mariánské Lázně Fault and in the Novohradské hory Mts. and their foothills - were surveyed by...
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Protein composition of the cytoskeleton of protists
Švagr, Eva ; Hampl, Vladimír (advisor) ; Pánek, Tomáš (referee)
While we have a good understanding of the roles of actin and tubulin filaments in the cell cytoskeleton, intermediate filaments (IFs) are often overlooked. However, the importance of IFs becomes quite apparent, as proteins similar to IF proteins have been identified in many protist cells. This holds particularly for the cells of protists, where even the functions of some members of the of actin and tubulin superfamilies remain unclear. Intermediate filaments are still not well established as components of protist cytoskeletons, in contrast to their more thoroughly studied counterparts in Metazoa. Protist and metazoan IF proteins are dissimilar in their sequence; however, they share similarities in structure, and they assemble autonomously into analogous filaments. IF-like proteins have been localized to striated fibers or unique cytoskeletal components in several organisms, even though not much is known about the protein composition of these striated fibers to date. This suggests that IF-like proteins might be a universally present component of these striated fibers often seen in protist cells. Keywords: Protists, cytoskeleton, microtubules, microfilaments, intermediate filaments, fibrils, protein composition
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Dynamics of glacial lakes and hydrological conditions of a glacial-morainic complex (Adygine, northern Tien Shan)
Falátková, Kristýna ; Janský, Bohumír (advisor) ; Petrakov, Dmitry (referee) ; Pánek, Tomáš (referee)
The thesis deals with hydrological conditions in a proglacial environment, focusing on the development of glacial lakes and the assessment of their susceptibility to outburst. The study site is the Adygine glacier-moraine complex located in the north-facing valley of the Kyrgyz Ridge, northern Tien Shan, Kyrgyzstan, at an altitude of 3400-4200 m a.s.l. In the past 50 years, the receding glacier allowed formation of several lakes, which form a three-level cascade and are fed by glacier meltwater. Below the glacier, there is a complex of several generations of moraines, through which the glacier meltwater is routed downstream. The aims of the work were to evaluate the development of individual lakes, their susceptibility to sudden outburst and possible triggers, to estimate the probable development of the site in the future, to analyse the hydrological regime of the lakes and to obtain basic information on the subsurface flow of water from the site to the stream. For the purposes of assessing the development of the lakes, the data obtained in the field (geodetic surveying of a shore line, bathymetric measurements), as well as satellite and aerial images were used. Fluctuation of lake water level was monitored by pressure sensors and the processing of this data allowed to analyse the hydrological...
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Diversity and evolution of anaerobic Heterolobosea
Pánek, Tomáš ; Čepička, Ivan (advisor) ; Oborník, Miroslav (referee) ; Vávra, Jiří (referee)
9 ABSTRACT This thesis is focused on the phylogeny, diversity, and cell structure of obligately anaerobic Heterolobosea (Excavata: Discoba). Using culture-based approach, we have discovered their hidden species diversity and described 11 new species. Our phylogenetic analyses showed that obligately anaerobic heteroloboseans evolved at least twice independently (Creneidae and Psalteriomonadidae). Psalteriomonadidae is a major anaerobic lineage of Heterolobosea as it includes 16 species and 5 genera. Most psalteriomonadids have acristate mitochondria, although Pseudoharpagon pertyi probably possesses remnants of mitochondrial cristae. Creneidae are represented just by a single species, Creneis carolina, which displays unique cell structure and life cycle. Architecture of its flagellar apparatus is not readily comparable with any other eukaryotes and at least some cytoskeletal elements have undergone unprecedented evolutionary positional changes. Anaerobic heteroloboseans are just rarely detected by environmental, culture-independent approaches. Thus, it is impossible to estimate their real species diversity. Nevertheless, our current data on anaerobic jakobids, another lineage of Discoba, indicates that the culture-based approach is relatively powerful to discover species diversity of anaerobic excavates. In...
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The in-store communication of Sberbank CZ
Pánek, Tomáš ; Jesenský, Daniel (advisor) ; Klimeš, David (referee)
Thesis focuses on the in-store marketing communication of Sberbank CZ, a. s., specifically on multisensory marketing and its usage by the bank. The first theoretical part defines the specific field of services marketing with its five most common key characteristics, defines in-store marketing communication and its importance as well as focuses on the multisensory marketing with deep down focus on each of our senses. In the second part of the thesis one can find the description of current use of multisensory marketing inside the Sberbank CZ branches using theoretical knowledge from the theoretical part also supplemented with summaries and further recommendations. The main focus is to describe current state and to find another opportunities in order to provide deeper multisensory experience inside bank branches to the visitors.
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Evolution of anaerobic Heterolobosea
Pánek, Tomáš ; Čepička, Ivan (advisor) ; Oborník, Miroslav (referee)
Heterolobosea is a group of mainly free-living amoebae, flagellates and amoeboflagellates closely related to Euglenozoa and Jakobida (supergroup Excavata). At least two heterolobosean lineages have reduced their mitochondria and live in low concentrations of oxygen (Psalteriomonadidae and extremely halophilic Pleurostomum). Moreover, some other presumably anaerobic species have been described in aerobic heteroloboseid genera, but their sequence data are still missing. The aim of this study is to recognize the diversity and phylogenetic position of both already described and novel non-hypersaline anaerobic heteroloboseans. We have isolated and cultivated 34 strains of free-living heterolobosean flagellates, amoebae and amoeboflagellates from freshwater, brackish and marine microoxic/anoxic habitats. 33 of these strains constitute a single clade (Psalteriomonadidae). We recognize 2 new genera and 3 new species. Phylogenetic analysis of SSU rDNA showed the genus Percolomonas is polyphyletic. The similar morphology of species formally placed within the genus Percolomonas is probably plesiomorphic. Finally, the marine strain PC4AM is morphologically unique and its morphology can not be compared with other heteroloboseans and eukaryotes. It is probably the most derived heterolobosean. Its cell structure...
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