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Use of Molecular Biology Techniques for Identification and Analysis of Probiotic Bacteria
Konečná, Jana ; Doškař, Jiří (referee) ; Kráčmar, Stanislav (referee) ; Obruča, Stanislav (advisor)
Isolation of deoxyribonucleic acid (DNA) is an important step in the molecular diagnostics of microorganisms. A high quality of isolated DNA is necessary for DNA amplification by the polymerase chain reaction (PCR). The conventional DNA isolation using phenol-chloroform extraction and DNA precipitation in ethanol is time-consuming and requires the use of toxic phenol. Alternative method of DNA isolation is use of commercially available kits which, however, are expensive and their efficiency is low. Magnetic separation techniques using magnetic solid particles are one of modern methods to speed up the nucleic acids isolation. The aim of this work was to use two different types of magnetic particles for solid-phase DNA extraction. Magnetic microparticles P(HEMA – co – GMA) containing –NH2 group and nanoparticles PLL, whitch contains polylysine. The amounts of DNA in separation mixtures were measured using ultraviolet spectrophotometry (UV). The first experimental conditions were tested on chicken erythrocytes DNA. Phosphate buffer (pH 7, 7.6 and 8) was used for adsorption of DNA on magnetic particles. It was shown that approximately almost one half of DNA was adsorbed on the particles. The elution conditions of DNA were also optimized. Secondly, bacterial DNA was tested. After optimalization, the developed method was used for DNA isolation from real food supplements. This DNA eluted from the particles was in PCR ready quality. High resolution melting (HRM) curve analysis is a simple, low-cost method for amplicon discrimination and easy connection with real-time polymerase chain reaction (PCR). In this thesis, we report rapid species identification of strains belonging to the Lactobacillus group using HRM-PCR. Three different DNA isolation methods were used in this work: phenol extraction, separation using magnetic particles and commercial kit. Ten sets of targeted gene fragments primers (LAC1 – LAC2, LAC2 – LAC4, P1V1 – P2V1, Gro F – Gro R, 3BA-338f – Primer 1, V1F – V1R, CHAU - V3F – CHAU - V3R, CHAU - V6F – CHAU - V6R, poxcDNAFw – poxPromRVC, poxcDNAFw – poxPromRVT) were tested for amplification of the 16S rRNA gene. Use of GroF/R and LAC2/4 primers pairs successfully identify strains belong to the Lactobacillus group. The variance between used extraction methods for evidence of HRM curves was found.
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Isolation of DNA from probitic products using solid carriers
Bonczek, Ondřej ; Horák, Daniel (referee) ; Rittich, Bohuslav (advisor)
Microbial DNA was isolated from lysed cells of Lactobacillus genus in probiotic products. Reversible adsorption DNA on the surface of carboxyl coated nonporous poly(2-hydroxyethyl methacrylate-co-glycidyl methacrylate) (P(HEMA-co-GMA)) magnetic particles and silicagel coated manganase Perovskite nanoparticles. DNA was adsorbed on the surface of the particles in the presence of 16 % poly(ethylenglycol) (PEG 6000) and 2 M sodium chloride (NaCl) concentrations. The adsorbed DNA was released from particles by low ionic strength TE buffer (pH= 8.0). The quality of isolated DNA was checked by spectrofotometric measurement and PCR amplification. DNA samples isolated using magnetic particles and phenol extraction method (control method) were PCR-ready. The DNA isolated from lysed cells of probiotic products was quantificated in real-time qPCR.
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Fluorescence detection in pathogen analysis
Tomečková, Kristýna ; Kristýna, Zemánková (referee) ; Bezděková, Jaroslava (advisor)
This bachelor thesis deals with isolation and detection of bacteria. The used method is called molecular imprinting and is connected with fluorescence microscopy. The theoretical part concentrates on comparison of the developed method with methods that have been used till now. The practical part describes preparation and optimization molecularly imprinted polymers. These polymers were prepared on two different carriers – multititration wellplate and magnetic particles. The bacteria used as imprinted template was Enterococcus faecalis. Staphylococcus aureus was used as its competitor.
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Isolation and detection of DNA from plant species important for food prodution
Orel, Matúš ; Rittich, Bohuslav (referee) ; Kovařík, Aleš (advisor)
In the food industry, it is very important to take care of the quality, safety and organoleptic properties of the products supplied. For this reason, food must be checked. However, not all information can be found using conventional techniques such as immunoassays, chromatographic techniques, etc. DNA-based techniques can be used for these cases where traditional procedures are insufficient. Among them, the best known technique is PCR. The aim of the thesis was to isolate DNA from vegetable samples (broccoli, beetroot, carrot and pepper). DNA was isolated using the magnetic particle method and the traditional CTAB method. Both methods were able to isolate the DNA from the vegetable samples in quality and at a concentration suitable for PCR, where the 35S rDNA gene region was amplified (more precisely about 700 bp of the 18S-ITS1-5,8S region). After amplification, the PCR products were subjected to restriction reactions and the results compared to bioinformatic analysis. These steps have succeeded in finding suitable enzymes for diferentiation of PCR products from the tested vegetable species.
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DNA isolation from selected vegetable products (paprika)
Gőghová, Sabína ; Kuderová,, Alena (referee) ; Kovařík, Aleš (advisor)
The diploma thesis deals with micromethod of DNA isolation from ten differently processing food products containing pepper (Capsicum annum). PCR ready DNA was isolated by magnetic particles PGMA functionalized by carboxyl groups from homogenates prepared in lysis buffer with CTAB. Quantity and quality of DNA was estimated using spectrophotometric measurements and verified using PCR methods with primers specific for plant rDNA. Quality of isolated DNA varied depending on processing technology. DNA isolated from smoked grinded peppers and from heat treated food products was degraded and amplified with primers F_26S and R_26S (PCR product 220 bp) in contrary to the primers F_18S and R_5.8S (PCR product 700 bp). DNA isolated from the other food products was amplified with primers F_18S and R_5.8S (PCR product 700 bp). PCR product from one grinded pepper (Žitavská paprika) was cloned and sequenced.
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Diagnostics of genom conditioned diseases with the use of micro- and nanoparticles
Mondeková, Věra ; Prášek, Jan (referee) ; Provazník, Ivo (advisor)
The bachelor´s thesis discusses possibilities of viral genome´s detection through use of biosensors, more specifically through use of magnetic particles. The introductory part consists of brief characteristic of viruses, mentioned as originator of genom conditioned diseases, followed by chapters related to selected methods of nucleic acid´s extraction and analysis. The main part is dedicated to magnetic particles. The practical part of thesis deals with possibility of use of biosensors in specific viral pathogen´s detection, selection of biocompatible molecules suitable for magnetic particle modification and description of specific DNA sequence isolation procedure through use of magnetic particles.
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Identification of selected species of lactic acid bacteria in dairy products
Vystavělová, Růžena ; Trachtová, Štěpánka (referee) ; Rittich, Bohuslav (advisor)
Lactic acid bacteria are natural part of the human gastrointestinal tract. They are often used in food supplements and for the production of fermented dairy products. This thesis focuses on the identification of selected species of lactic acid bacteria and bifidobacteria in cheese and dairy products. Bacterial DNA was isolated by magnetic particles P(HEMA-co-GMA) from crude cell lysates from 9 products. Isolated DNA was amplified in genus-specific and species-specific polymerase chain reactions (PCR). The obtained amplicons were detected by agarose gel electrophoresis. The results of PCR were compared with those provided by the manufacturers and there has been declared a match.
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Application of magnetic particles for isolation and purification of DNA
Němeček, Milan ; Španová, Alena (referee) ; Rittich, Bohuslav (advisor)
With a development of molecular biology methods it is an increasing interest in new procedures of DNA isolation of high quality. DNA isolation is performed on crude cell lysates by many techniques e.g. phenol extraction, salting out or adsorption on solid phase. Classical DNA isolation, such as phenol extraction is quite complicated and time consuming. New alternative methods of DNA isolation was development using reverse immobilizing DNA to a solid phase. Widespread is the use of the magnetic particles as carriers, which allow the isolation of DNA in high quality directly from crude cells lysates of complex samples. The current method of DNA adsorption onto the surface of magnetic particles does not provided sufficiently pure DNA for analysis of some comlex samples (e.g. food). Some inhibitors of the polymerase chain reaction (PCR) are apparently adsorbed onto the tube wall and the next step of DNA elution leads to their release into the solution and cpnsequent negative effect on quality of DNA (e.g. decreasing of PCR amplification). The principle of the developed procedure is design a device, which utilizes transfer of magnetic particles by paramagnetic newddle from one to another Eppendorf tube, in which further processing of the sample extends. Transfer of magnetic particles with DNA using needle prevents transmission of contaminating impurities. The proposed device allows to realize above-mentioned procedure. The functionality of the device being tested in the isolation of plasmid pUC19 DNA from crude lysates of E. Coli JM 109 (pUC19).
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The use of magnetic particles for DNA isolation from selected spices
Gaňová, Martina ; Rittich, Bohuslav (referee) ; Kovařík, Aleš (advisor)
The isolation of DNA from plant tissue of the required quality is very complicated, especially because of the presence of substances that can interfere during amplification of DNA. These substances are mainly polyphenols, polysaccharides, proteins and various dyes. The chemical diversity of such materials can have a significant effect on the yield and quality of DNA using one isolation procedure. The main aim of the work was to evaluate the use of microisolation protocol for related matrices to the quality of the isolated DNA as well as the evaluation of the effect of inhibitors isolated with the nucleic acid to the amplification in the PCR. DNA was isolated from dried paprika (Capsicum annuum). In the first step, the samples were homogenized using a lysis reagent with cetyltrimethylammonium bromide. Subsequently, the DNA was purified by reversible adsorption on magnetic particles. It was tested six different modified particles. The concentration and purity of the obtained DNA was determined by spectrophotometry measuring the absorbance of the DNA solution in TE buffer. The quality of the DNA was confirmed by amplification in PCR. For the PCR were used primers specific for plant ribosomal DNA (rDNA). The presence of PCR products was detected by agarose gel electrophoresis. It was found out that used microassay is suitable for isolating of the DNA of the corresponding purity that is suitable for the genetic analysis by PCR. The differences were found between the magnetic particles that were tested for DNA isolation.
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