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Photobiont diversity in lichen thallus Psora decipiens
Jadrná, Iva ; Škaloud, Pavel (advisor) ; Peksa, Ondřej (referee)
Psora decipiens is a characteristic species of the terricolous lichen community Toninio-Psoretum decipientis distributed mostly on calcareous or basic substrates. The community consists in various modifications of lichens Placidium squamulosum, Toninia sedifolia, T. opuntioides, Fulgensia fulgens, F. bracteata and others. Photobionts of the lichen Psora decipiens were determined. Psora decipiens shared with Placidium sp. the single photobiont species, a common terrestrial alga Myrmecia israeliensis. Cloning of ITS rDNA revealed high intrathalline variability in M. israeliensis within a single lichen thallus. Several genotypes were often found in a thallus, uncovering either a high mutation rate of the algae or constant relichenization processes. Saxicolous Psora species (P. testacea, P. himalayana, P. valesiaca and P. rubiformis) had M. biatorellae as a photobiont, indicating a possible photobiont influence on substrate specifity of Psora lichens. Finally, the proper methodology used for identification of lichen photobionts is discussed. For a correct photobiont identification, morphological investigations of intrathaline diversity combined with coherent molecular techniques are needed. Such procedure was not applied in the former studies of Psora decipiens, resulting in a poor characterization of...
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A taxonomic study of Physconia muscigena group
Starosta, Jakub ; Svoboda, David (advisor) ; Šoun, Jaroslav (referee)
The principal goal of my study was to find if ecologically and chemically different populations of lichens in the Physconia muscigena (Ach.) Poelt group belong to several species or a single one. This study focused on the molecular and chemical investigations of mostly European and Canadian populations. I use sequence data from three genes (ITS rDNA, mtSSU rDNA and TEF1) for the reconstruction of phylogenetic trees. I investigate phylogenetic relationships among the closely related species P. muscigena, P. bayeri, P. rossica, and P. isidiomuscigena. Also, I wanted to detect any possible geographical or ecological trends among chemotypes and haplotypes. As an additional goal I checked the recent localities of P. muscigena in the Czech Republic for valorising its conservation status. Results show that: (1) sequenced data of ITS rDNA and TEF1 show high intraspecific variability in P. muscigena samples. This genetic variability does not correlate neither with geographical distribution nor thallus chemistry; (2) P. bayeri is synonymous with P. muscigena; (3) some samples P. muscigena contain new undetermined secondary metabolite, (4) Physconia muscigena has only three recent localities in Czech Republic. Key words: Physconia muscigena, Physconia bayeri, infraspecific variability, taxonomy, TEF1, ITS...
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Human gastrointestinal mycobiome in health and disease
Galanová, Natalie ; Kolařík, Miroslav (advisor) ; Hudcovic, Tomáš (referee)
This Bachelor thesis is a complex review of information about mycobiome of human digestive tract. It summarizes the known incidence, diversity and abundance of fungi in different parts of the gastrointestinal tract together with factors that determine composition of its communities. It also describes plentiful interactions with immune system, other microbes and between fungal species themselves. Then there is a brief remark about methodology that is in use for this subject together with its pros and cons. Thesis sums up and discusses current knowledge about the healthy mycobiome, highlighting cases, when it plays role in the formation of disbalance often resulting in an outbreak of a disease. The paper considers ecology and detailed interactions with the environment for Candida species, the dominant gastrointestinal fungus. Intestinal mycobiota has been lately purposed as an important factor in the development of certain local diseases, which include inflammatory bowel disease, ulcerative colitis and Crohn's disease, or irritable bowel syndrome. Moreover other seemingly unrelated diseases have been associated with a change in intestinal mycobiome in the recent years. Finally intestinal community plays with its immunogenic nature important role in defense mechanisms elsewhere within the body. Key...
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