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Evolution of mastigont in Excavata
Táborský, Petr ; Čepička, Ivan (advisor) ; Hampl, Vladimír (referee)
In recent years we have been discovering a huge diversity of eukaryotic organisms. One of the big super-groups is Excavata. Examination of the organisms from this group is fairly important as far as theoretical and practical reasons are concerned. A significant number of authors believe that there is the root of all eukaryotic organisms in this group. And what is more, a lot of studies prove the point. Within Excavata group we can find the organisms with the most primitive mitochondrial genome which is known. Several other representatives are an important human pathogenes. In the first part of the thesis I focus on the historical review of the creation of the super-group Excavata and I also include a part regarding the theory about Archezoa. The next section deals with the general description of mastigont (basal bodies and cytoskeleton that is associated with them). The last part presents mastigont descriptions of some derived representatives of Excavata. Some of these organisms may be free-living and some live inside other organisms.
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Morphological and molecular characterization of anaerobic members of the genus Andalucia (Excavata: Jakobida)
Táborský, Petr ; Čepička, Ivan (advisor) ; Škaloud, Pavel (referee)
Eukaryotic organisms are divided into about 30 groups today, yet there still reamain many groups whose classification in the eukaryotic tree we are not sure about. This study focused on jacobids, a evolutionary important protist group from the Excavata taxa. Together with Heterolobosea, Euglenozoa and Tsukubamonadida, jacobids constitue a Discoba subgroup of Excavata taxa. Jacobids are significant mainly for their mitochondrial genome, which structurally resembles the original α-proteobacterial genome of the free-living ancestor of mitochondria. Some jacobids have their mitochondrial genome simplified, making them potential candidates for a model group used to study the mitochondrial evolution. However, too few members of jacobid group have been identified so far and the exact phylogeny of the group must be thoroughly understood for the detailed study of mitochondria evolution. This study focuses on broadening the taxonomic coverage of the jacobid excavate protists Andalucia. Twenty new strains of Andalucia have been established into stable culture, their morphology was assessed and SSU rDNA sequenced. Based on the phylogenetic analysis, Andalucia incarcarata species divides into three morphologically almost indistinguishable lines representing three species. Further, this study characterized a...
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Evolution of mastigont in Excavata
Táborský, Petr ; Čepička, Ivan (advisor) ; Hampl, Vladimír (referee)
In recent years we have been discovering a huge diversity of eukaryotic organisms. One of the big super-groups is Excavata. Examination of the organisms from this group is fairly important as far as theoretical and practical reasons are concerned. A significant number of authors believe that there is the root of all eukaryotic organisms in this group. And what is more, a lot of studies prove the point. Within Excavata group we can find the organisms with the most primitive mitochondrial genome which is known. Several other representatives are an important human pathogenes. In the first part of the thesis I focus on the historical review of the creation of the super-group Excavata and I also include a part regarding the theory about Archezoa. The next section deals with the general description of mastigont (basal bodies and cytoskeleton that is associated with them). The last part presents mastigont descriptions of some derived representatives of Excavata. Some of these organisms may be free-living and some live inside other organisms.
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Cryptic diversity of free-living trichomonads and their phylogenetic position within Parabasalia
Céza, Vít ; Čepička, Ivan (advisor) ; Hampl, Vladimír (referee)
Trichomonads (Parabasalia) are anaerobic microeukaryotes classified in the supergroup Excavata. Inclusion of parabasalids within Excavata is exclusively based on the molecular- phylogenetic evidence. Over 400 species of parabasalids have been described so far, and the vast majority of them are endobiotic. In contrast, only few species of free-living parabasalids forming four independent lineages have been described (Pseudotrichomonas keilini, Ditrichomonas honigbergii, Monotrichomonas carabina, Honigbergiella sp., Tetratrichomonas undula, and Lacusteria cypriaca). Lacusteria cypriaca is a new species and genus described in our recent paper. In this paper we published the first two sequences of SSU rDNA from Pseudotrichomonas keilini as well. All of these lineages are likely secondarily free-living, and they developed from endobiotic ancestors. In addition to the already published Lacusteria cypriaca and Pseudotrichomonas keilini strains, we have recently obtained seven another isolates of free-living trichomonads (LAGOS2D, E2NT, CK, LAGOS2M, GR8, GOU23 LIVADIAN, and VAV1A1); from all of these isolates we sequenced SSU rDNA and performed phylogenetic analyses. These isolates split into four independent evolutionary lineages, which indicate that free-living parabasalids are more diversed and...
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