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Use of molecular techniques to characterize yeasts of the genus Metschnikowia
Schneiderwindová, Nicole ; Brázda, Václav (referee) ; Němcová, Andrea (advisor)
This diploma thesis deals with the possibilities of implementation and use of molecular methods for the characterization of yeasts of the genus Metschnikowia and the application of methods in biotechnology or the food industry. The theoretical part focuses on a brief description of yeast, specially selected species that were used during the practical part of the work, the possibilities of their use, and especially on a detailed description of all molecular techniques used. The practical part focuses on the optimization of the molecular methods, namely the method of pulsed gel electrophoresis and the method of denaturing gradient gel electrophoresis. Initially, yeast was cultured under optimal conditions that are specific to this genus. Furthermore, their DNA was isolated using isolation techniques, which were subsequently processed using PFGE and PCR–DGGE methods. The DNA isolation procedure needed to be optimized the most. Several optimizations of the concentration of lysis enzymes, especially the lyticase enzyme, were performed. It was also necessary to determine the correct ratio of low-melting agarose and isolated DNA, which was essential for the correct consistency of the isolated DNA blocks and their further application in PFGE analysis. Finally, the PFGE method was optimized, which brought the correct distribution of chromosomes, and it was possible to describe the individual chromosomes according to their size according to the standard used CHEF of the yeast Hansenula wingei. To properly optimize the DGGE analysis process itself, it was first necessary to isolate the yeast DNA using a kit, then it was used as a template for the PCR reaction. The annealing temperature was also optimized for the individual groups of primers. The amplicons obtained by this reaction were separated by the DGGE method. This technique mainly required the optimization of basic parameters such as the range of the denaturation gradient or the total separation time. According to the measurement results, it can be determined that the process of yeast DNA isolation and their subsequent analysis using molecular methods of pulsed gel electrophoresis and denaturing gradient gel electrophoresis was successful. We were able to describe the genome and determine the number of chromosomes in all used yeast species of the genus Metschnikowia at least partially.
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Control of metabolism of carotenogenic yeasts on molecular level
Pokrývková, Zuzana ; Kočí, Radka (referee) ; Márová, Ivana (advisor)
This diploma thesis deals with the molecular characterization of carotenogenic yeasts. The techniques used for the analysis of the conserved regions of the D1/D2 rDNA region of the 26S ribosomal large subunit region and the ITS1 and 5,8-ITS2 regions were nested PCR and DGGE. The results of DGGE show that all analyzed yeast strains have very similar sequences of these regions The yeast Rhodotorula mucilaginosa with the collection number CCY 20-7-28 showed differences from the other carotenogenic yeast strains. As a part of melucular characterisation using ribosomal gene sequences, eight yeast strains were examinated for substrate utilisation tests using different substrates. Characterisation of growth and metabolite production was tested in each strain too. The next aim of this thesis was to prepare a carotenoid yeast strain characterized by overproduction of metabolites, in particular carotenoids and lipids,. Yeasts were subjected to a random mutation caused by UV irradiation and the influence of this mutantagen onthe production of metabolites was evaluated. As a candidate yeast strain C. capitatum CCY 10-1-2 was selected. This selection was based on previous studies due to its good production of lipids using waste glycerol as asubstrate. This strain was subsequently adapted to waste whey, glycerol, and a glucose as a basic carbon source.
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Characterization of carotenogenic yeasts using molecular techniques
Kostovová, Iveta ; Čarnecká, Martina (referee) ; Márová, Ivana (advisor)
The aim of this master’s thesis was focused on characterization of carotenogenic yeast using molecular techniques. For this usage, interspecific variables of strongly conserved sequences of genomic DNA, especially rDNA D1/D2 large ribosomal subunit and ITS1 and 5,8-ITS2 rDNA regions were amplified. These sequences were subjected analysed by DGGE method, which approved differences of S. roseus in all analyzed rDNA sequencies compared to the other analyzed carotenogenic yeasts. Parameters of PFGE and isolation procedure of the intact DNA were optimized for caryotypic yeast characterization. At all, nine of carotenogenic yeast strains Rhodotorula, Sporobolomy-ces, Cystofilobasidium a Phaffia were analyzed by this techniques. Further part of this thesis was focused to application of molecular methods to analysis of region D1/D2 of large ribosomal subunit in mutant carotenogenic yeast strains. Mutant strains were pre-viously adapted to waste substrates - pasta and glycerol, and stability of their production properties was verified.
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DNA isolation and identification of nonpathogenic species of clostridia isolated from cheeses
Sedláček, Zbyněk ; Eva, Kvasničková (referee) ; Rittich, Bohuslav (advisor)
In the food industry are requested speedy and accurate methods for identification of bacteria in microbiological testing of products. Molecular diagnostic methods are based on isolation of DNA from bacterial cells which is amplified in polymerase chain reaction (PCR). The result is fragment DNA about specific size, characteristic for genus or species of bacteria. The aim of the work was isolation of PCR-ready DNA. DNA has been isolated from 8 strains of genus Clostridium. Procedure of cell lysis was optimized in order to find the optimal concentration of EDTA and proteinase K in lysing buffer. DNA was isolated by phenol extraction and using magnetic microspheres. Concentrations 10 mM of EDTA and 10 l of proteinase K (100 g/ml) were the best for cell lysis for isolation of DNA by phenol extraction. Concentrations 10 mM of EDTA and 15 l of proteinase K (100 g/ml) were the best for cell lysis for isolation of DNA by magnetic microspheres. Isolated DNA was checked by gel electrophoresis, quantificated by spectrophotometry and tested in PCR. Individuals species were distinguished in denaturing gradient gel electrophoresis (DGGE).
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Use of DGGE to analysis and identification of selected microorganisms
Jankeje, Kristína ; Čarnecká, Martina (referee) ; Márová, Ivana (advisor)
Presented diploma thesis is focused on use of DGGE to analysis and identification of selected microorganisms. PCR-DGGE is a method that allows direct characterization of the microbial community in the natural environment without necessity of cultivation. A literature review is devoted to the principle of the method, current applications and its limitations too. In experimental part microbial DNA was isolated and used as a template for PCR reaction. Microbial DNA was then amplified using the universal eukaryotic primers that target the D1/D2 domain of the 26S subunit of ribosomal DNA. To improve specificity and sensitivity of detection nested PCR was chosen using outer and inner primer pairs. Generated amplicons (250 bp) were consequently separated by DGGE. The analysis of selected microorganisms by DGGE technique was performed after optimization of electrophoresis conditions (in particular the denaturing gradient extent and separation time). Despite the optimization, mutual differentiation among individual yeast strains was not possible since each reference strain was represented by several bands in the same positions. In conclusion DGGE profile obtained from wine musts is discussed. Present bands suggest the major presence of non-Saccharomyces yeasts, yeast-like strain A. pullulans is present in the minority and Saccharomyces yeasts are probably present too. The technique remains open for further optimization, particularly as regards the conditions of polymerase chain reaction.
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DNA extraction from cheeses for polymerase chain reaction analysis
Mohelský, Tomáš ; Rittich, Bohuslav (referee) ; Španová, Alena (advisor)
This work was focused on DNA isolation from cheeses for the use in polymerase chain reaction. First, there was optimised the procedure of homogenisation of different types of cheeses from commercial sources, cell lysis and DNA isolation. DNA was isolated using magnetic microspheres and phenol extraction. It was shown that the DNA was amplified in PCR for domain Bacteria after dilution. Next, there was optimised the procedure of DNA isolation from fresh cheeses and from contaminated fresh cheeses and their pickles. DNA from all samples was amplified in PCR. The presence of DNA of domain Bacteria and yeast DNA was demonstrated. In the last part of the work, there were optimised the preparation of PCR mixtures and bacterial DNA amplification in PCR with primers with clamp (F357-GC and R518). Synthetized PCR products were analysed using DGGE. It was shown that amplicons of DNA isolated from cheeses and pickles differ in positions and numbers. Larger number of bands of different intensities was detected after amplification of DNA isolated from contaminated pickles.
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Use of molecular techniques to characterize yeasts of the genus Metschnikowia
Schneiderwindová, Nicole ; Brázda, Václav (referee) ; Němcová, Andrea (advisor)
This diploma thesis deals with the possibilities of implementation and use of molecular methods for the characterization of yeasts of the genus Metschnikowia and the application of methods in biotechnology or the food industry. The theoretical part focuses on a brief description of yeast, specially selected species that were used during the practical part of the work, the possibilities of their use, and especially on a detailed description of all molecular techniques used. The practical part focuses on the optimization of the molecular methods, namely the method of pulsed gel electrophoresis and the method of denaturing gradient gel electrophoresis. Initially, yeast was cultured under optimal conditions that are specific to this genus. Furthermore, their DNA was isolated using isolation techniques, which were subsequently processed using PFGE and PCR–DGGE methods. The DNA isolation procedure needed to be optimized the most. Several optimizations of the concentration of lysis enzymes, especially the lyticase enzyme, were performed. It was also necessary to determine the correct ratio of low-melting agarose and isolated DNA, which was essential for the correct consistency of the isolated DNA blocks and their further application in PFGE analysis. Finally, the PFGE method was optimized, which brought the correct distribution of chromosomes, and it was possible to describe the individual chromosomes according to their size according to the standard used CHEF of the yeast Hansenula wingei. To properly optimize the DGGE analysis process itself, it was first necessary to isolate the yeast DNA using a kit, then it was used as a template for the PCR reaction. The annealing temperature was also optimized for the individual groups of primers. The amplicons obtained by this reaction were separated by the DGGE method. This technique mainly required the optimization of basic parameters such as the range of the denaturation gradient or the total separation time. According to the measurement results, it can be determined that the process of yeast DNA isolation and their subsequent analysis using molecular methods of pulsed gel electrophoresis and denaturing gradient gel electrophoresis was successful. We were able to describe the genome and determine the number of chromosomes in all used yeast species of the genus Metschnikowia at least partially.
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Control of metabolism of carotenogenic yeasts on molecular level
Pokrývková, Zuzana ; Kočí, Radka (referee) ; Márová, Ivana (advisor)
This diploma thesis deals with the molecular characterization of carotenogenic yeasts. The techniques used for the analysis of the conserved regions of the D1/D2 rDNA region of the 26S ribosomal large subunit region and the ITS1 and 5,8-ITS2 regions were nested PCR and DGGE. The results of DGGE show that all analyzed yeast strains have very similar sequences of these regions The yeast Rhodotorula mucilaginosa with the collection number CCY 20-7-28 showed differences from the other carotenogenic yeast strains. As a part of melucular characterisation using ribosomal gene sequences, eight yeast strains were examinated for substrate utilisation tests using different substrates. Characterisation of growth and metabolite production was tested in each strain too. The next aim of this thesis was to prepare a carotenoid yeast strain characterized by overproduction of metabolites, in particular carotenoids and lipids,. Yeasts were subjected to a random mutation caused by UV irradiation and the influence of this mutantagen onthe production of metabolites was evaluated. As a candidate yeast strain C. capitatum CCY 10-1-2 was selected. This selection was based on previous studies due to its good production of lipids using waste glycerol as asubstrate. This strain was subsequently adapted to waste whey, glycerol, and a glucose as a basic carbon source.
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DNA extraction from cheeses for polymerase chain reaction analysis
Mohelský, Tomáš ; Rittich, Bohuslav (referee) ; Španová, Alena (advisor)
This work was focused on DNA isolation from cheeses for the use in polymerase chain reaction. First, there was optimised the procedure of homogenisation of different types of cheeses from commercial sources, cell lysis and DNA isolation. DNA was isolated using magnetic microspheres and phenol extraction. It was shown that the DNA was amplified in PCR for domain Bacteria after dilution. Next, there was optimised the procedure of DNA isolation from fresh cheeses and from contaminated fresh cheeses and their pickles. DNA from all samples was amplified in PCR. The presence of DNA of domain Bacteria and yeast DNA was demonstrated. In the last part of the work, there were optimised the preparation of PCR mixtures and bacterial DNA amplification in PCR with primers with clamp (F357-GC and R518). Synthetized PCR products were analysed using DGGE. It was shown that amplicons of DNA isolated from cheeses and pickles differ in positions and numbers. Larger number of bands of different intensities was detected after amplification of DNA isolated from contaminated pickles.
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Characterization of carotenogenic yeasts using molecular techniques
Kostovová, Iveta ; Čarnecká, Martina (referee) ; Márová, Ivana (advisor)
The aim of this master’s thesis was focused on characterization of carotenogenic yeast using molecular techniques. For this usage, interspecific variables of strongly conserved sequences of genomic DNA, especially rDNA D1/D2 large ribosomal subunit and ITS1 and 5,8-ITS2 rDNA regions were amplified. These sequences were subjected analysed by DGGE method, which approved differences of S. roseus in all analyzed rDNA sequencies compared to the other analyzed carotenogenic yeasts. Parameters of PFGE and isolation procedure of the intact DNA were optimized for caryotypic yeast characterization. At all, nine of carotenogenic yeast strains Rhodotorula, Sporobolomy-ces, Cystofilobasidium a Phaffia were analyzed by this techniques. Further part of this thesis was focused to application of molecular methods to analysis of region D1/D2 of large ribosomal subunit in mutant carotenogenic yeast strains. Mutant strains were pre-viously adapted to waste substrates - pasta and glycerol, and stability of their production properties was verified.
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