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Evaluation of Organisms Relationship by Genomic Signal Processing
Škutková, Helena ; Tkacz, Ewaryst (referee) ; Schwarz,, Daniel (referee) ; Provazník, Ivo (advisor)
This dissertation deals with alternative techniques for analysis of genetic information of organisms. The theoretical part presents two different approaches for evaluation of relationship between organisms based on mutual similarity of genetic information contained in their DNA sequences. The first approach is currently standardized phylogenetics analysis of character based records of DNA sequences. Although this approach is computationally expensive due to the need of multiple sequence alignment, it allows evaluation of global and local similarity of DNA sequences. The second approach is represented by techniques for classification of DNA sequences in a form of numerical vectors representing characteristic features of their genetic information. These methods known as „alignment free“ allow fast evaluation of global similarity but cannot evaluate local changes. The new method presented in this dissertation combines the advantages of both approaches. It utilizes numerical representation similar to 1D digital signal, i.e. representation that contains specific trend along x-axis. The experimental part of dissertation deals with design of a set of appropriate tools for genomic signal processing to allow evaluation mutual similarity of taxonomically specific trends. On the basis of the mutual similarity of genomic signals, the classification in the form of dendrogram is applied. It corresponds to phylogenetic trees used in standard phylogenetics.
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Phylogenomics, genome size evolution and repeat dynamics in the genus Amomum Roxb. (Zingiberaceae)
Hlavatá, Kristýna ; Fér, Tomáš (advisor) ; Haevermans, Thomas (referee) ; Zedek, František (referee)
Amomum Roxb. s.l. (black cardamom) is a complicated genus in the ginger family Zingiberaceae (subfamily Alpinioideae) that according to some definitions includes groups of species recognized as separate genera, e.g. genus Elettariopsis Baker. Phylogenetic studies have so far failed to elucidate both the position of Amomum within Alpinioideae and the relationship between Amomum and other genera like Elettariopsis. In this work, Amomum was subjected to a detailed morphological analysis of the largest possible sampling, together with a phylogenetic analysis. Amomum was recircumscribed, Amomum s.s. and three new genera were established, three genera were resurrected, and genus Elettariopsis was merged into Amomum. Meanwhile, new species were described and others epitypified. A well-resolved nuclear-gene phylogeny of Amomum s.s. was obtained using next-generation sequencing (Hyb-Seq) and showed the existence of four clades (A, B, C, D) within the genus. Clade D, the former genus Elettariopsis, was further divided into three subclades (D1-D3). A chloroplast DNA-based phylogeny supported this structure, but additional phylogenies based on ribosomal DNA were incongruent with it, indicating that the frequently used ITS marker and other rDNA markers may not be suitable for reconstructing deeper phylogenetic...
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Iron-Sulfur cluster assembly in Monocercomonoides exilis
Vacek, Vojtěch ; Hampl, Vladimír (advisor) ; Balk, Janneke (referee) ; Tsaousis, Anastasios (referee)
In the search for the mitochondrion of oxymonads, DNA of Monocercomonoides exilis - an oxymonad isolated from the gut of Chinchilla, was isolated and its genome was sequenced. Sequencing resulted in a fairly complete genome which was extensively searched or genes for mitochondrion related proteins, but no reliable candidate for such gene was identified. Even genes for the ISC pathway, which is responsible for Fe-S cluster assembly and considered to be the only essential function of reduced mitochondrion-like organelles (MROs), were absent. Instead, we were able to detect the presence of a SUF pathway which functionally replaced the ISC pathway. Closer examination of the SUF pathway based on heterologous localisation revealed that this pathway localised in the cytosol. In silico analysis showed that SUF genes are highly conserved at the level of secondary and tertiary structure and most catalytic residues and motifs are present in their sequences. The functionality of these proteins was further indirectly confirmed by complementation experiments in Escherichia coli where SUF proteins of M. exilis were able to restore at least partially Fe-S cluster assembly of strains deficient in the SUF and ISC pathways. We also proved by bacterial adenylate cyclase two-hybrid system that SufB and SufC can form...
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Iron-Sulfur cluster assembly in Monocercomonoides exilis
Vacek, Vojtěch ; Hampl, Vladimír (advisor) ; Balk, Janneke (referee) ; Tsaousis, Anastasios (referee)
In the search for the mitochondrion of oxymonads, DNA of Monocercomonoides exilis - an oxymonad isolated from the gut of Chinchilla, was isolated and its genome was sequenced. Sequencing resulted in a fairly complete genome which was extensively searched or genes for mitochondrion related proteins, but no reliable candidate for such gene was identified. Even genes for the ISC pathway, which is responsible for Fe-S cluster assembly and considered to be the only essential function of reduced mitochondrion-like organelles (MROs), were absent. Instead, we were able to detect the presence of a SUF pathway which functionally replaced the ISC pathway. Closer examination of the SUF pathway based on heterologous localisation revealed that this pathway localised in the cytosol. In silico analysis showed that SUF genes are highly conserved at the level of secondary and tertiary structure and most catalytic residues and motifs are present in their sequences. The functionality of these proteins was further indirectly confirmed by complementation experiments in Escherichia coli where SUF proteins of M. exilis were able to restore at least partially Fe-S cluster assembly of strains deficient in the SUF and ISC pathways. We also proved by bacterial adenylate cyclase two-hybrid system that SufB and SufC can form...
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Anaerobic ciliates as a model group for studying the biodiversity and symbioses in anoxic environments
Rotterová, Johana ; Čepička, Ivan (advisor) ; Gentekaki, Eleni (referee) ; Silberman, Jeffrey David (referee)
Ciliates are also of the most extensively studied and diverse groups of unicellular eukaryotes, and yet, their anaerobic representatives have been largely neglected; in part due to culturing difficulties. Although all main ciliate lineages contain anaerobes, their diversity and evolution of anaerobiosis are especially poorly understood and just starting to gain attention. In fact, Ciliophora is an excellent model group to study adaptations to life in anoxia, since it, apart from the aerobic majority, includes free-living and endobiotic obligately anaerobic lineages, facultative anaerobes, microaerophiles, and microaerotolerant species. The diversity of Metopida, the free-living order of obligately anaerobic class Armophorea, has been partially revised and significantly broadened during the past years, including numerous redescriptions using modern methods, as well as the description of novel families Tropidoatractidae and Apometopidae, several genera, and multiple species. Oxygen plays a crucial role in ATP production via oxidative phosphorylation that takes place in the mitochondrion in most known eukaryotes. Nevertheless, anaerobic ciliates, among many other eukaryotes that have adapted to low oxygen concentrations or even its absence, have modified their mitochondria and energetic metabolism to...
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Evaluation of Organisms Relationship by Genomic Signal Processing
Škutková, Helena ; Tkacz, Ewaryst (referee) ; Schwarz,, Daniel (referee) ; Provazník, Ivo (advisor)
This dissertation deals with alternative techniques for analysis of genetic information of organisms. The theoretical part presents two different approaches for evaluation of relationship between organisms based on mutual similarity of genetic information contained in their DNA sequences. The first approach is currently standardized phylogenetics analysis of character based records of DNA sequences. Although this approach is computationally expensive due to the need of multiple sequence alignment, it allows evaluation of global and local similarity of DNA sequences. The second approach is represented by techniques for classification of DNA sequences in a form of numerical vectors representing characteristic features of their genetic information. These methods known as „alignment free“ allow fast evaluation of global similarity but cannot evaluate local changes. The new method presented in this dissertation combines the advantages of both approaches. It utilizes numerical representation similar to 1D digital signal, i.e. representation that contains specific trend along x-axis. The experimental part of dissertation deals with design of a set of appropriate tools for genomic signal processing to allow evaluation mutual similarity of taxonomically specific trends. On the basis of the mutual similarity of genomic signals, the classification in the form of dendrogram is applied. It corresponds to phylogenetic trees used in standard phylogenetics.
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