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Diversity and taxonomy of fungi inhabiting extremely acidic and saline soils of natural and anthropogenic origin in the Czech Republic
Hujslová, Martina ; Kubátová, Alena (advisor) ; Tomšovský, Michal (referee) ; Gunde-Cimerman, Nina (referee)
Highly acidic environments represent some of the most extreme habitats for the microbial growth. For a long time it has been assumed that these sites are populated exclusively by prokaryotes. However recently, eukaryotic organisms including fungi have been found to be abundant and important component of acidophilic communities. Concerning fungal diversity only fragmentary data are available indicating that highly acidic sites harbour specific and low-diversified fungal communities dominated by dematiaceous fungi. In the present work we focused on the cultivable mycobiota occupying highly acidic (pH < 3) soils which are at the same time saline (sulfate-rich) and are located at geographically isolated localities in the Czech Republic. This study should provide a deep insight into the diversity and biogeographical pattern of acidophilic/tolerant fungi. A combination of classical and specialized cultivation techniques was successfully applied since it significantly contributed to the broadening of the detected fungal spectrum. The revealed fungal assemblages inhabiting highly acidic sites worldwide are closely similar and differ from the ones known from less acidic habitats. The core of the fungal assemblage under study consisted of phylogenetically unrelated and often globally distributed fungi...
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Ecophysiology of microscopic fungus Pseudogymnoascus destructans
Homutová, Karolína ; Kubátová, Alena (advisor) ; Baldrian, Petr (referee)
A microscopic fungus Pseudogymnoascus destructans (Ascomycota: Pseudeurotiaceae) causes illness known as white-nose syndrome (WNS) causing death of bats during hibernation. The illness occurs in the North America and in Europe. The fungus is characteristic by asymmetrically curved conidia, by slow growth and growth at low temperatures (below 20 řC). The aim of this study is to clarify properties responsible for unique ecelogy of Pseudogymnoascus destructans by comparison with ecological related or unrelated pathogenic or nonpathogenic fungi. This part includes study of tolerance to physiological stresses and recognition of spectrum of utilizating nutrients (compounds of carbon, nitrogen, phosphorus, sulphur and nutrient supplements). Testing to physiological stresses should help to estimate a potentiality of fungus to spread out of caves. The last aim is to develop a selective isolation medium for P. destructans. Influence of several types of physiological stress (e.g. UVA, UVA with UVB, 25 řC, 30 řC, 37 řC and dryness) was investigated with fluorescent stain propidium iodide (PI) by flow cytometry. The spores of Pseudogymnoascus destructans and three fungi from underground spaces were not viable after 3 weeks at 37 řC. Other stresses did not cause a decreasing of viability or some stresses caused...
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Diversity and taxonomy of Trichoderma in the Czech Republic
Valinová, Šárka ; Kubátová, Alena (advisor) ; Nováková, Alena (referee)
Genus Trichoderma - anamorph of the genus Hypocrea (Hypocreaceae, Hypocreales, Sordariomycetes, Ascomycota) belongs to saprotrophic filamentous micromycetes. The representatives of this genus are known primarily as cosmopolitan inhabitants of soil ecosystems, including leaf litter and woody debris. This work summarizes the results of the study of isolates belonging to the genus Trichoderma originating from the territory of the Czech Republic, mainly from soil and leaf litter. During the study, altogether 267 isolates were analysed. For all of the isolates the following methods were used: phenotypic characterisation, UP-PCR fingerprinting, gene sequencing in tef 1α and ITS regions, and in the strain AK 115/00 also in rpb2 region. The main result of the study was the identification of 21 species of genus Trichoderma belonging into 4 groups and discovery of one isolate of species yet unknown to science. Species T. crassum, T. gamsii, T. ghanense, T. rossicum and T. longipile were found in the Czech Republic for the first time. According to the literature review and results of this study, 34 different Trichoderma species is currently known from the Czech Republic. In the work there is also discussed low reliability of identification of certain species based only on phenotypic characters. Key words:...
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Microscopic fungi in caves and other underground shelters
Horáková, Karolína ; Kubátová, Alena (advisor) ; Hujslová, Martina (referee)
This Bachelor thesis is meant as a literature search concerned with diversity of microscopic fungi in caves, prospectively in underground spaces which were made by humankind. The caves represent unique environment for living organisms which is characteristic with specific microclimatic conditions and with deficient sources of nutrients. I have concentrated my focus to micromycetes which were isolated from sediments, atmosphere, dead insect and excrements in caves. The next part of my Bachelor thesis is aimed at species Geomyces destructans which causes so called white-nose syndrome illness - geomycosis on hibernating bats. It is an actual problem which interests scientists such as mycologists, zoologists and parasitologists.
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Decomposition of leaf litter by microscopic fungi in anthropogenic habitats
Bukovská, Petra ; Gryndler, Milan (referee) ; Kubátová, Alena (advisor)
V letech 2006 - 2008 byl na dvou antropogenních stanovištích s výskytem biologické půdní krusty proveden terénní experiment s listovým opadem břízy a modelovou celulózou využívající metodu opadových sáčků. Rychlost dekompozice opadu i celulolytická aktivita byla na obou stanovištích extrémně nízká. Diverzita společenstva mikroskopických hub na opadu, zjišťovaných izolační metodou a metodou inkubace opadu ve vlhkých komůrkách, však byla srovnatelná s diverzitou známou z přirozených lesních ekosystémů temperátního pásma. Také sukcesní změny společenstva hub pozorované na obou lokalitách odpovídaly v základních rysech údajům z jiných typů stanovišť. Metodou ITS-TRFLP kombinovanou s použitím taxonomicky specifických primerů byla odhalena značná diverzita chytridií a naopak jen velmi nízká diverzita bazidiomycetů. Na stanovišti s vyšší mírou antropogenního stresu byla zjištěna nižší diverzita hub, značně odlišná skladba společenstva a nižší dekompoziční aktivita. Na opadu studovaných stanovišť byly pozorovány i druhy, u kterých nebyla dosud známa tolerance k přítomným antropogenním stresům, a druhy dosud nepopsané. Powered by TCPDF (www.tcpdf.org)
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Diabetes mellitus negatively affects male reproductive parameters in vivo
Valášková, Eliška ; Žatecká, Eva ; Pavlínková, Gabriela ; Bohuslavová, Romana ; Dorosh, Andriy ; Elzeinová, Fatima ; Kubátová, Alena ; Margaryan, Hasmik ; Pěknicová, Jana
According to the World Health Organization (WHO), 15% of couples in reproductive age suffer from infertility problems, and up to 60% of cases are caused by male factor. This could be caused by genetic background, environmental factors and various diseases, including diabetes mellitus (DM). However, the impact of DM on male fertility is not fully understood. . The aim of this study was to investigate the effects of DM on reproductive parameters and sperm quality, using mouse model. DM (type 1) was induced by Streptozotocin in FVB inbred mouse strain. Mice with blood sugar levels higher than 13.9 mmol/L were considered diabetic. After 4 weeks of diabetes exposure, diabetic males were bred with wild type females and transgenerational effect of DM was assessed. Selected morphological, cellular, and molecular parameters of diabetic males and their male offspring were compared to appropriate controls. There was an increased in sperm fragmentation and abnormalities of sperm morphology in diabetic mice in both generations. An increased staining with apoptotic marker annexin V was also detected in the diabetic groups. Furthermore, a presence of protamines as major sperm nuclear proteins was analysed. Protamine 1 to protamine 2 ratio (P1/P2), a marker of male fertility, was altered in sperms of experimental diabetic animals in both generations. Our findings indicate that DM type 1 negatively affects sperm quality and P1/P2 ratio and this negative effect is transmitted to the progeny
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