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Degradation of fats in wastes
Artýszková, Jana ; Flodrová, Dana (referee) ; Omelková, Jiřina (advisor)
Submitted master’s thesis is focused on the study of possibilities of lipids degradation in particular wastewaters originating in food industry or restaurants. The effort is given to the employment of lipolytic activity presenting microorganisms. In the literature review, wastewater treatment with aim on the sludge management and fat separators are described, as a way how to pre-treat these wastewaters. In this part the enzymes lipases of microbial origin are researched from point of view of their production conditions and possible applications. The experimental part is dedicated to the research of optimization of cultivation conditions for lipases production employing selected microorganisms (Bacillus subtilis, Geobacillus thermodenitrificans, G. thermocatenulatus and mixed bacterial culture Thermus and Bacillus) and a commercial formulation (Sany Duo Spezial). Lipases production and growth of microorganisms are determined spectrofotometrically on various concentrations of lipids. Moreover, employing the solid nutrition medium, the effect of detergents onto the Bacillus subtilis culture was assessed, since detergents are generally abundant in this particular wastewaters. As a conclusion, vide supra mentioned microorganisms were characterized according to their abilities to degrade triacylglycerols.
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Expression, localisation, and interactome of the RefZ protein during sporulation in Bacillus subtilis.
Paliesková, Anna Mária ; Krásný, Libor (advisor) ; Nešvera, Jan (referee)
Bacillus subtilis is a gram-positive sporulating bacterium. Under unfavorable conditions, it initiates the sporulation process that results in a resistant spore. The transcription factor Spo0A is a master regulator of sporulation initiation. The hallmark of sporulation is the formation of an asymmetric septum near a cell pole, which divides the cell into the larger mother cell and smaller prespore. The asymmetric septum is localized at 1/6 of the cell length relative to the nearer pole. One of the players involved in this localization is the RefZ protein, referred to as the FtsZ regulatory protein, which forms the Z-ring. The Z-ring is important for the formation of both the vegetative (mid-cell) and asymmetric septa. RefZ facilitates the relocalization of the Z-ring from midcell to the poles at an early stage of sporulation. RefZ also binds DNA (RefZ binding motifs [RBMs]) near the ori site of the chromosome, thereby promoting precise positioning of the chromosome arms during sporulation. The entire sporulation process is controlled by a cascade of compartment-specific sporulation σ factors that recognize specific consensus sequences in the promoter regions of genes, thereby allowing RNA polymerase to initiate transcription of sporulation-specific genes. These σ factors ensure spatially and...
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The omega subunit of Bacillus subtilis RNA polymerase.
Mikesková, Klára ; Krásný, Libor (advisor) ; Nešvera, Jan (referee)
Transcription is catalysed by the enzyme RNA polymerase (RNAP). RNAP contains a core made up of two α subunits, one of each β, β'and ω. These subunits are conserved in all bacteria. The ω subunit is a small subunit with a molecular weight of 7.6 kDa that binds β'. ω is important for the folding and integrity of RNAP and promoter selection. This was shown by experiments performed with Gram-negative bacteria but the knowledge about in Gram-positive bacteria is minimal. In my Diploma Thesis, I characterized from the model Gram-positive bacterium from the phylum Firmicutes, Bacillus subtilis. First, I prepared various expression strains for isolation of Bacillus subtilis ω. Then, I successfully isolated the ω subunit, which was the main initial aim of this Diploma Thesis. Subsequently, I tested the influence of the ω subunit on in vitro transcription by RNAP associated with the primary σA factor and alternative σF and σE factors that regulate sporulation in Bacillus subtilis. I also evaluated the effect of , a small RNAP subunit found in Firmicutes, both alone and in combination with . The experiments revealed that ω stimulated transcription both from vegetative promoters and sporulation-related promoters. Moreover, this stimulation was synergistically amplified by the δ subunit. This nicely...
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Transmission and detection of the crayfish plague pathogen under experimental conditions
Svoboda, Jiří ; Petrusek, Adam (advisor) ; Fiala, Ivan (referee)
The crayfish plague pathogen, Aphanomyces astaci, is one of the most serious threats to European indigenous crayfish species, e.g., the noble crayfish (Astacus astacus). The only way to protect susceptible crayfish species from the disease is to prevent the dispersion of the pathogen to their populations. One of the most important sources of the crayfish plague pathogen in Central Europe is the spiny-cheek crayfish (Orconectes limosus), a species of North American origin, which can carry the parasite in its cuticle for years. Some literature sources claimed that the pathogen dispersion from the American vectors is restricted to periods of moulting or to the time before and after the crayfish death. However, experimental evidence for such hypotheses was lacking. The main aim of my thesis was to test these predictions, and the alternative scenario that the crayfish plague pathogen can be transmitted from the infected spiny-cheek crayfish also in other periods. For this purpose, experiments were set up to investigate A. astaci transmission from infected spiny-cheek crayfish to non-infected spiny-cheek or noble crayfish. As expected, the pathogen was transmitted to noble crayfish much more easily than to the uninfected American host. Nevertheless, we succeeded in the pathogen transmission also among spiny-cheek...
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Transmission and detection of the crayfish plague pathogen under experimental conditions
Svoboda, Jiří ; Petrusek, Adam (advisor) ; Fiala, Ivan (referee)
The crayfish plague pathogen, Aphanomyces astaci, is one of the most serious threats to European indigenous crayfish species, e.g., the noble crayfish (Astacus astacus). The only way to protect susceptible crayfish species from the disease is to prevent the dispersion of the pathogen to their populations. One of the most important sources of the crayfish plague pathogen in Central Europe is the spiny-cheek crayfish (Orconectes limosus), a species of North American origin, which can carry the parasite in its cuticle for years. Some literature sources claimed that the pathogen dispersion from the American vectors is restricted to periods of moulting or to the time before and after the crayfish death. However, experimental evidence for such hypotheses was lacking. The main aim of my thesis was to test these predictions, and the alternative scenario that the crayfish plague pathogen can be transmitted from the infected spiny-cheek crayfish also in other periods. For this purpose, experiments were set up to investigate A. astaci transmission from infected spiny-cheek crayfish to non-infected spiny-cheek or noble crayfish. As expected, the pathogen was transmitted to noble crayfish much more easily than to the uninfected American host. Nevertheless, we succeeded in the pathogen transmission also among spiny-cheek...
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Degradation of fats in wastes
Artýszková, Jana ; Flodrová, Dana (referee) ; Omelková, Jiřina (advisor)
Submitted master’s thesis is focused on the study of possibilities of lipids degradation in particular wastewaters originating in food industry or restaurants. The effort is given to the employment of lipolytic activity presenting microorganisms. In the literature review, wastewater treatment with aim on the sludge management and fat separators are described, as a way how to pre-treat these wastewaters. In this part the enzymes lipases of microbial origin are researched from point of view of their production conditions and possible applications. The experimental part is dedicated to the research of optimization of cultivation conditions for lipases production employing selected microorganisms (Bacillus subtilis, Geobacillus thermodenitrificans, G. thermocatenulatus and mixed bacterial culture Thermus and Bacillus) and a commercial formulation (Sany Duo Spezial). Lipases production and growth of microorganisms are determined spectrofotometrically on various concentrations of lipids. Moreover, employing the solid nutrition medium, the effect of detergents onto the Bacillus subtilis culture was assessed, since detergents are generally abundant in this particular wastewaters. As a conclusion, vide supra mentioned microorganisms were characterized according to their abilities to degrade triacylglycerols.
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