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Development and differentiation of different types of yeast colonies: Regulation of metabolic diversification and development of cells with novel properties
Maršíková, Jana
Yeasts are unicellular organisms, but on a solid substrate they are capable of forming complex organized structures that behave like primitive multicellular organisms. Examples of these structures include colonies and biofilms, whose cells interact with each other, coordinate their growth and development, differentiate spatially and form specialized cell subpopulations in which specific processes and regulatory pathways occur. The basis of cellular differentiation and specialization is the formation of gradients of nutrients, metabolites and signaling molecules. Thus, multicellular yeast communities differ significantly from planktonic populations in their characteristics. The aim of this work is to increase knowledge related to the development and differentiation of both smooth and structured colonies of the yeast Saccharomyces cerevisiae. The literature introduction of the thesis provides an overview of the current knowledge on the development of yeast colonies and biofilms, especially of S. cerevisiae species, and also includes selected regulations important for the formation of multicellular populations. The thesis provides insights into the antagonistic function of the transcriptional regulators Cyc8p and Tup1p in the development of structured biofilm colonies. Genome-wide transcriptomic...
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Analysis of metabolites produced by yeast colonies and biofilms
Karásek, Filip ; Palková, Zdena (advisor) ; Dostál, Jiří (referee)
Some time ago it was shown (proved, described) that bacteria can communicate and regulate a gene expression by using small molecules. This phenomenon is called quorum sensing. The same phenomenon has been recently described in yeast. In yeast there are still many questions about the mechanism of sensing via small molecules. Few works and publications have described the impact of some small molecules, such as phenylethylalcohol or tryptophol, on morphology on Saccharomyces cerevisiae cell. The knowledge about the impact of the small molecules on the yeast multicellular community, like colonies, is still very limited these days. The aims of this work are analysis of exometabolites produced by colonies of different yeast strains cultivated on various solid complex media, by an untarged metabolomic approach. In accordance with the result of the exometabolites analyses we are going to test the impact of the selected substance on Saccharomyces cerevisiae colony morphology. The third part of this work is about the construction of Saccharomyces cerevisiae strains with deletion or lowering the expression of genes which encode proteins that are important in decarboxylation step of the Ehrlich pathway. Key word: Saccharomyces cerevisiae, microcolonies, tryptophol, isoamyl alcohol, isovaleric acid, colony...
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Development and differentiation of different types of yeast colonies: Regulation of metabolic diversification and development of cells with novel properties
Maršíková, Jana ; Palková, Zdena (advisor) ; Heidingsfeld, Olga (referee) ; Demnerová, Kateřina (referee)
Yeasts are unicellular organisms, but on a solid substrate they are capable of forming complex organized structures that behave like primitive multicellular organisms. Examples of these structures include colonies and biofilms, whose cells interact with each other, coordinate their growth and development, differentiate spatially and form specialized cell subpopulations in which specific processes and regulatory pathways occur. The basis of cellular differentiation and specialization is the formation of gradients of nutrients, metabolites and signaling molecules. Thus, multicellular yeast communities differ significantly from planktonic populations in their characteristics. The aim of this work is to increase knowledge related to the development and differentiation of both smooth and structured colonies of the yeast Saccharomyces cerevisiae. The literature introduction of the thesis provides an overview of the current knowledge on the development of yeast colonies and biofilms, especially of S. cerevisiae species, and also includes selected regulations important for the formation of multicellular populations. The thesis provides insights into the antagonistic function of the transcriptional regulators Cyc8p and Tup1p in the development of structured biofilm colonies. Genome-wide transcriptomic...
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Růst Mycobacterium smegmatis na agarovém médiu a agarovém médiu pokrytém celofánovou folií - morfologická a proteomová studie
Ramaniuk, Volha ; Weiser, Jaroslav (advisor) ; Beranová, Jana (referee)
Biofilm formation is one of the most common bacterial survival strategies. Majority of bacterial species are able to form these three-dimensional structures, including pathogens like Mycobacterium tuberculosis. Representatives of Mycobacterium genus widely occur in the nature, although they can cause serious problems when they appear in medical equipment and artificial replacements of the human body. Non-pathogenic Mycobacterium smegmatis mc2 155 was used as a model organism in our experiments. We investigated morphology of the three- and six-day-old colonies (in fact biofilms) on agar and agar covered with cellophane using Stereo microscope and Scanning Electron Microscope. We found that a type of surface as well as a carbon source has a great influence on the morphology of the M. smegmatis colonies. We isolated proteomes from the agar and cellophane cultures and from planktonic culture. Two-dimensional electrophoresis was used as the main proteomic method. Proteomic data were analyzed using PDQuest software. Then the sets of proteins detected by qualitative and quantitative analyses were compared using Venn diagrams. As a result, we recognized 7 unique proteins that might be specific for recognition and adhesion of bacteria to the cellophane, no unique protein in agar proteome and 46 unique...
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Interaction of Whi3 and Yap6 under mild osmotic stress
Voloshin, Danila ; Schierová, Michaela (advisor) ; Heidingsfeld, Olga (referee)
Natural strains of the Saccharomyces cerevisiae growing on solid médium form structured, biofilm -like colonies. This ability is depended on the surface adhesin Flo11p. The expression of the FLO11 gene is upregulated by the RNA-binding protein Whi3p, which is likely to have a negative effect on the level of the transcription factor Yap6p. The aim of this study was to determine whether Yap6p affects colony morphology and FLO11 expression. Analysis of FLO11 expression using the fluorescent proteins pFlo11-GFP and Flo11p-DsRed in WHI3-deletion strains demonstrated a negative effect of Yap6p on FLO11 expression and confirmed changes in the effect of Yap6p on FLO11 expression in the presence of NaCl. In the strain overexpressing YAP6, the fluorescence values of pFlo11-GFP and Flo11p-DsRed were lower than in the strain with deletion of the YAP6 and in the presence of NaCl there was observed the largest increase in fluorescence. Although Yap6 protein is thought to have a negative effect on FLO11 expression under standard culture conditions, it seems to be responsible for a significant increase in FLO11 expression in the presence of mild osmotic stress. In WHI3-deletion strains, there was observed a significant increase in structuredness of colonies growing in the presence of NaCl. Analysis of structured...
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Růst Mycobacterium smegmatis na agarovém médiu a agarovém médiu pokrytém celofánovou folií - morfologická a proteomová studie
Ramaniuk, Volha ; Weiser, Jaroslav (advisor) ; Beranová, Jana (referee)
Biofilm formation is one of the most common bacterial survival strategies. Majority of bacterial species are able to form these three-dimensional structures, including pathogens like Mycobacterium tuberculosis. Representatives of Mycobacterium genus widely occur in the nature, although they can cause serious problems when they appear in medical equipment and artificial replacements of the human body. Non-pathogenic Mycobacterium smegmatis mc2 155 was used as a model organism in our experiments. We investigated morphology of the three- and six-day-old colonies (in fact biofilms) on agar and agar covered with cellophane using Stereo microscope and Scanning Electron Microscope. We found that a type of surface as well as a carbon source has a great influence on the morphology of the M. smegmatis colonies. We isolated proteomes from the agar and cellophane cultures and from planktonic culture. Two-dimensional electrophoresis was used as the main proteomic method. Proteomic data were analyzed using PDQuest software. Then the sets of proteins detected by qualitative and quantitative analyses were compared using Venn diagrams. As a result, we recognized 7 unique proteins that might be specific for recognition and adhesion of bacteria to the cellophane, no unique protein in agar proteome and 46 unique...
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Differentiation of yeast colonies and development of new approaches to monitor oxygen and nutrient availability
Vopálenská, Irena ; Janderová, Blanka (advisor) ; Demnerová, Kateřina (referee) ; Pichová, Iva (referee)
Yeast Saccharomyces cerevisiae as an unicellular organism is one of the best-studied experimental organisms. It is an important model organism for the study of intracellular processes of eukaryotic cells. Yeasts are also social organisms with cell-to-cell communication able to form organized multicellular structures (colonies and biofilms). Yeast and other microorganisms in nature prefer to form colonies on solid substrates rather than to grow as "planktonic" single cells (Palková, 2004; Wimpenny, 2009). The yeast S. cerevisiae typically forms colonies, biofilms were described only rarely. Yeast colonies exhibit an organized morphological pattern characteristic of each particular yeast strain (Kocková-Kratochvílová, 1982). This work is focusing on morphology and differentiation of the S. cerevisiae colonies of common laboratory strains forming less structured colonies, and strains of the Σ1278b genetic background forming highly structured "fluffy" colonies. It shows that polarized budding pattern and especially cell ability to form aggregates enable development of structured morphology. During development of "fluffy" colonies two differently regulated events of dimorphic switch from yeast form to filamentous growth occur. One of these events is dependent on the surface glycoprotein, Flo11p flocculin. This...
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