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Klinicky významné druhy kvasinek a jejich interakce s hostitelem
Novosadová, Zuzana ; Palková, Zdena (advisor) ; Beranová, Jana (referee)
Pathogenic yeasts are nowadays a serious threat for mammalian host. They can cause dangerous diseases, which in many cases even result in death. Pathogens increase the chances of systemic infections by many virulence mechanisms. Experiments addressing the pathogenhost interactions are crucial for defeating these types of infections within the human body. Host-pathogen interactions are very complex and include all components of multicellular host organism. Recently, scientists have focused on the interaction of the mammalian immune system and pathogenic yeasts in more detail. This work summarises interactions of pathogen with selected host cells, especially with macrophages. Yeast pathogens, especially Candida albicans, are capable of influencing the gene expression in interacting cells. These pathogens are capable of modulating the expression while engulfed inside macrophages and other cells of the immune system. Pathogenic yeasts can also change the overall characteristics of their surrounding environment. C. albicans can sense pH and influence it. Therefore, it can increase its virulence by the changes of pH leading to autoinduction of morphological transitions. This work briefly reviews how selected yeast pathogens influence their surroundings while interacting within the host organism. Deeper...
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The comparison of the performace of carbocyanine dyes disC3(3) a diSC3(5) in fluorescent probing of yeast cell membrane potential.
Matunová, Petra ; Plášek, Jaromír (advisor) ; Krůšek, Jan (referee)
Membrane potential represents a voltage across a membrane and it is an important parameter that helps to describe processes in cells. Carbocyanine fluorescent probes diS-C3(3) and diS-C3(5), for which a common short chemical name 3,3'- dipropylthiadicarbocyanine iodide is used, are suitable for monitoring membrane potential changes of cells in which microelectrodes can not be used because of a small size of the cells. These changes can be measured on the scale of mV. A spectral analysis of cell suspensions containing a fluorescent probe makes it possible to determine the ratio of extracellular and intracellular concentrations of the probe. Using it we can calculate the value of membrane potential changes which can be induced by an outer stimulus. This Bc. thesis presents a comparison of the rate of accumulation of the above mentioned fluorescent probes in yeast cells, as well as experiments aimed for studying an inuence of different substances and their various concentrations on free and bound component of the dye.
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Characterisation of potassium cation transport systems in the yeast Zygosaccharomyces rouxii
Stříbný, Jiří ; Hodek, Petr (advisor) ; Schierová, Michaela (referee)
Characterization of potassium cation transport systems in the yeast Zygosaccharomyces rouxii Potassium has become absolutely necessary cation for living cells, including yeasts, because it plays several important roles in physiological processes. Intracellular concentration of K+ in yeasts is usually between 200 mM and 300 mM, while the external K+ concentration is ranging from molar to micromolar. To adapt to environments with low K+ content, yeast cells employ various K+ high-affinity uptake systems, e.g. Trk, Hak and K+ -ATPase, that provide cells with the sufficient amount of potassium. The recent release of the complete sequence of the osmotolerant yeast Zygosaccharomyces rouxii genome allowed us to search homologues of the known yeast potassium uptake systems. We have found just one gene encoding a putative potassium transporter homologous to the S. cerevisie TRK1. For the characterisation of transport properties and physiological roles of the product of this gene, named ZrTRK1, three approaches have been used. First, the IT tools serve to analyse sequence characteristics, phylogenetic relationships etc. The second approach involves cloning of the gene and its expression in a S. cerevisiae mutant strain lacking its own two Trk systems, characterisation of transformants' growth phenotypes and...
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Study of the mammalian oncogenic transcription factors in the yeast model
Novák, Josef ; Šťovíček, Vratislav (referee) ; Zámostná, Blanka (advisor)
Yeast serves as a useful tool for studying cellular processes and therefore a large amount of techniques and protocols has been developed. There are special methods for studying the transcriptional factors in yeast, such as modified yeast two-hybrid screens, yeast one-hybrid screens and systems studying ability of transcription factors to transactivate a reporter gene. Oncogenes from AP-1 complex, Myc and Myb protein families are described in this work. Using a yeast model the structural-functional properties of proteins can be easily studied and in some cases even their ability of oncogenic transformation can be predicted (FASAY or ability of c-Myc to transactivate a reporter gene). However, results from yeast models must be confirmed in mammalian cells. 1
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The molecular mechanism of CSL protein participation in oxidative stress response in Schizosaccharomyces pombe
Daněk, Petr ; Převorovský, Martin (advisor) ; Sipiczki, Matthias (referee)
Redox homeostasis maintenance is important for proper organism and cell function, for while relatively low amount of reactive oxygen (and nitrogen) species contributes to the fine tuning of signal transduction, excessive concentration of ROS (oxidative stress) has demonstrably harmful effects and is tightly connected to many pathological states. Cells therefore evolved broad palette of antioxidant mechanisms that express striking level of conservation among different species. Large, intricate stress response signaling networks have been already described; nonetheless, novel molecules employed in stress-related signaling are still being discovered. Several studies recently suggested transcription factors CSL, proteins essential for regulation of metazoan development as effectors of Notch signaling, are also involved in response to oxidative stress. The fission yeast Schizosaccharomyces pombe, well established model of response to various stresses, comprises two paralogs of CSL proteins - Cbf11 and Cbf12. We have found cells depleted of cbf11 are highly resistant to hydrogen peroxide. This resistance appears to be caused by upregulation of important stress responsive genes including ctt1, gst2, pyp2, and atf1. Cbf11 is therefore negative regulator of these genes, which suppresses their expression...
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Proteome and Metabolome Changes in Selected Organisms under Stress
Halienová, Andrea ; Kráčmar, Stanislav (referee) ; Čertík, Milan (referee) ; Šucman, Emanuel (referee) ; Márová, Ivana (advisor)
Living conditions of every organism are influenced by various factors at this time. Some of them have positive effect on organism, some negative. Basic condition for surviving is the ability to resist and adapt to changing metabolic and living conditions. Every single stress effect can lead to changes in metabolism but organisms have ability to develope sufficient mechanisms for stress response. Some of them are similar for all living organisms (enzyme production, endogenous primary stress metabolites) some of them are specific for certain organism or stress type. Cell stress response can be observed on different levels (proteomic, genomic, metabolomic). In proper conditions it can be used indrustrially. In this work, influences of various stress factors were studied. These factors were applied on selected organisms – carotenogenic yeast and plant materials. Yeast stress response was induced by osmotic and oxidation stress factors. Changes on proteomic level and in production of selected secondary metabolites were observed. Proteome was analyzed by 1D and 2D electrophoresis with subsequent analysis of proteins by mass spectrometry. Yeast strain Rhodotorula glutinis CCY 20-2-26 showed the best adaptation to stress factors, which was moreover accompanied by overproduction of carotenoids. This finding can be premise for next industrial production of carotenoids. In plant samples predominantly enzymes and metabolites involved in antioxidant response were studied.
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Characterisation of the Physical Chemical Processes Using the Fractal and Harmonic Analysis
Haderka, Jan ; Nešpůrek, Stanislav (referee) ; Mikula,, Milan (referee) ; Zmeškal, Oldřich (advisor)
Existuje mnoho různých způsobů jak analyzovat disperzní systémy a fyzikálně chemické processy ke kterým v takových systémech dochází. Tato práce byla zaměřena na charakterizaci těchto procesů pomocí metod harmonické fraktální analýzy. Obrazová data sledovaných systémů byly analyzovány pomocí waveletové analýzy. V průběhu práce byly navrženy různé optimalizace samotné analýzy, převážně zaměřené na odstranění manuálních operací během analýzy a tyto optimalizace byly také inkorporovány do softérového vybavení pro Harmonickou Fraktální Analýzu HarFA, který je vyvíjen na Fakultě chemické, VUT Brno.
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Microscope Image Processing
Janda, Ondřej ; Ošmera, Pavel (referee) ; Matoušek, Radomil (advisor)
This diploma thesis deals with image processing of microbiological data. Firstly the brief introduction to biological basics is given. Secondly we take focus on basic and used image processing methods. Integral part of this thesis is working application witch uses image processing methods on input data. Creating user interface for this application is also part of this work. Documentation is provided.
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Monitoring of the influence of indigenous culture of yeasts on the fermentation process of making wine
Michálek, Petr ; Molnárová,, Jana (referee) ; Vránová, Dana (advisor)
This thesis deals with the identification of wine yeasts isolated from the grape must using PCR-RFLP method. The yeasts were isolated from Pinot Noir grape variety must. Grapes were grown and produced in accordance with the requirements placed on organic and integrated farming. Samples were processed in the laboratory, where pure cultures of individual yeast were obtained. A commercial kit was used for yeast DNA isolation. Obtained DNA was used for further analysis. Using the polymerase chain reaction and the primers ITS1 and ITS4 a specific segment of 5.8S rDNA-ITS region was amplified. The PCR products were then detected by electrophoresis in an agarose gel, and after a subsequent purification, three restriction enzymes: HaeIII, HinfI and HhaI were subjected to restriction analysis. The DNA was digested to fragments specific for yeast species and they were detected by agarose electrophoresis. Similarity of these isolates was compared using BioNumerics program and the result is dendrogram of genetic similarity of isolated yeast. The basic chemical analysis of samples must was also performed.
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Monitoring of the influence of commercial culture of yeasts on fermentation wine making process
Šerý, Filip ; Vojtíšková, Marie (referee) ; Vránová, Dana (advisor)
This diploma thesis focuses on isolation and taxonomic classification of yeast species isolated during the red wine (Pinot noir) fermentation. Grapes were grown under organic and integrated farming in South Moravia wine region, Czech Republic. Processing was controlled – for inoculation was used strain Saccharomyces cerevisiae BS6. Polymerase chain reaction followed by restriction fragment lenght polymorphism of PCR-amplified fragments (PCR-RFLP) was used for yeast species identification. For DNA analysis we used coding region of 5.8S ITS rDNA which was amplified using ITS1-ITS4 primers. Amplicon was digested by three restriction endonucleases - HaeIII, HinfI and HhaI. Isolates were divided into eleven groups using UPGMA cluster analysis (software BioNumerics). We identified following yeast species: Candida valida, Candida vini, Issatchenkia occidentalis, Pichia fermentans, Saccharomyces cerevisiae and Zygosaccharomyces bailii. We were not able to identify some yeast species. Differences between organic and integrated farming were demonstrated with varying composition of yeast species.
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