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Cytologická studie modelů DNA metylace a metylace histonů u lidských buněčných linií
Skalníková, M. ; Bártová, Eva ; Kozubek, Stanislav ; Kozubek, Michal
Epigenetic processes are defined as heritable changes in genome function that occur without a change in DNA sequence. Gene expression, chromosome segregation, DNA replication, repair, and recombination all act, not on DNA alone, but on the chromatin template. DNA methylation, along with histone lysine methylation, establishes the framework for long-term epigenetic maintenance. The discovery that enzymes can (re)organise chromatin into accessible and inaccessible configurations revealed epigenetic mechanisms that considerably extend the information potential of the genetic code. In mammals, heterochromatin is characterised by DNA methylation at CpG dinucleotides and methylation at lysine 9 of histone 3 (H3-K9), whereas euchromatin is associated with methylation at lysine 4 of histone 3 (H3-K4).
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Prolyl endopeptidase of the blood fluke Schistosoma mansoni
Fajtová, Pavla ; Konvalinka, Jan (advisor) ; Ryšlavá, Helena (referee)
Prolyl endopeptidase SmPEP from the blood fluke Schistosoma mansoni is investigated here for the first time. This enzyme is potentially interesting as a drug target for the treatment of schistosomiasis. SmPEP was detected in the extract of adult worms by enzyme activity and immunoreactivity. Enzymatically active SmPEP was produced in the E. coli expression system and was chromatographically purified. The pH optimum of recombinant SmPEP was about 8. Substrate specificity analysis revealed that SmPEP cleaved peptide substrates by endopeptidase activity, however, macromolecular substrates were not fragmented. The residue preferences in the positions P3 to P1' were determined using synthetic fluorogenic peptide substrates. SmPEP was found to be highly sensitive to the inhibition by Z-Ala-Pro-CMK and Z-Arg-Pro-CHO. Primary screening of crystallization conditions for recombinant SmPEP was performed. " (In Czech)"
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Expression of the recombinant extracellular parts of leukocyte receptors AICL a NKR-P1CBALB
Čonka, Martin ; Novák, Petr (advisor) ; Cebecauer, Marek (referee)
v anglickém jazyce NK cells represent a population of lymphocytes which are able to kill certain tumor cells or virally infected cells. The subject of the diploma thesis is a mouse NK cell receptor mNKR- P1CBALB and a human leukocyte receptor hAICL. The mNKR-P1CBALB belongs to the activating receptors and is able to activate the cytotoxic functions of NK cells. The hAICL receptor is a ligand to the NKp80 which is an activating receptor of NK cells. Interaction between these two proteins leads to the activation of effector functions of NK cells as well. The aim of this work was the preparation of the recombinant extracellular parts of receptors mNKR-P1CBALB and hAICL, the optimalization of their in vitro refolding and the characterization of proteins using mass spectrometry. The proteins samples will be used for further structural study of the extracellular parts of these leukocytes receptors.
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Use of Waste Substrates to Production of Enriched Yeast Biomass
Starečková, Terezie ; Demnerová, Kateřina (referee) ; Vávrová, Milada (referee) ; doc.PharmDr.Petr Babula, Ph.D. (referee) ; Márová, Ivana (advisor)
Yeasts are like other organisms constantly exposed to environmental influences. Their survival depends on the skills to adapt to environmental changes, including the ability to use various alternative sources of nutrients. In presented PhD thesis carotenogenic yeast belonging to the genera Rhodotorula, Sporobolomyces and Cystofilobasidium were tested for ability to use of selected waste substrates, and also subjected to several types of exogenous stress effects and mutations in order to increase the production of microbial biomass enriched with specific metabolites. As alternative nutrient sources derived from waste substrates from agricultural and farm production apple peel, pulp, corn germ and more were tested. Yeasts were also exposed to osmotic, oxidative and combined stress (benefits of various concentrations of NaCl and H2O2 to the culture media), followed by metal ions of selenium and chromium in concentrations of 0.01 mM, 0.1 mM and 1 mM. The effect of mutagen methanesulfonic acid ethyl ester was tested too. In all experiments the adaptivity of cells, morphological changes, color pigments produced by the media while some important fungal metabolites production and changes in chromosomal DNA fragmentation were analyzed. In order to evaluate potential changes in the yeast genome after treatment with mutagen and stress factors methods for isolation of intact chromosomal DNA and DNA analysis by pulsed field gel electrophoresis was optimized. The amount of produced metabolites was mainly analyzed by RP-HPLC with UV/VIS and MS detection. The work has been shown that most strains are able to use waste substrates and produced selected target metabolites. Biomass, for example, in R. aurantiaca on apple fiber was about 7 g/l and in C. capitatum cultivated on modified whey reached to 9 g/l. Amount of produced carotenoids by R. aurantiaca cultivated on wheat germ and maize after enzymatic hydrolysis by F. solani was 1.01 mg/g and S. roseus on pasta 4.3 mg/g. The values of ergosterol synthesis in R. aurantiaca are on the apple shells around 4.8 mg/g, in S. roseus on pasta with the enzymatic hydrolysis of P. chrysosporium 8.9 mg/g. The best substrate for biomass production and induction of carotenoids are waste substartes containing a mixture of simple and complex carbohydrates enriched with the addition of nitrogen compounds. Potential cytotoxic effect of stress factors of low concentrations was demonstrated. Red yeast genome was able to distribute by optimized PFGE, the karyotype of tested yeasts contain 11 or more chromosomes with visible differences between yeast species and genera. During exchange internship the ability of recombinant yeast S. cerevisiae to convert xylose to xylitol, which would be achieved by increasing the production of bioethanol as alternative fuel sources was studied. It turned out that both ligninocellulose materials to bioethanol production, as well as various waste substrates for microbial synthesis of carotenoids would reduce costs for industrial production of yeast metabolites, as well as to reduce the negative burden on the environment.
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The study of the role of biotransformational enzymes in chemical carciogenesis
Kondrová, Eliška ; Souček, Pavel (advisor) ; Skálová, Lenka (referee) ; Vobořilová, Jana (referee) ; Bořek Dohalská, Lucie (referee)
In vitro biotransformation studies are an integral part of both toxicological research and drug development. They allow for a significant reduction of tests on human volunteers and provide detailed information about the metabolism of a given compound. Due to limited availability of human liver tissue, it is necessary to make use of alternative model systems and model animal species in the study of the interactions between biotransformation enzymes and xenobiotics. Since the activities of the most important human biotransformation enzymes are absent in the most commonly used laboratory species, rat, information gained in experiments with minipigs is very valuable. Recombinant human biotransformation enzymes expressed in bacteria can be used in biotransformation studies in the form of isolated bacterial membranes. These model systems provide information about the metabolism of a given xenobiotic by a defined enzyme and thein advantages compared to purified enzymes include low cost and quicker and easier preparation with lower loss of enzymatic activity during isolation. The aims of this study were: 1) To prepare a model system with recombinant human biotransformation enzymes expressed in bacterial membranes and to compare the properties of this system with minipig liver microsomes. To assess the usefulness of...
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Pentraxin PTX3 - a new marker of immunopathological inflammation.
Kondělková, Kateřina ; Jílek, Petr (advisor) ; Andrýs, Ctirad (referee)
Pentraxin 3 (PTX3) is a newly identified acute phase reactant which shares some structural and some functional properties with CRP, classical short pentraxin. On the other hand, PTX3 displays unique biological properties of its own, including a possible role in the pathogenesis of cardiovascular diseases and in processes accompanying the natural evolution of surgical wounds. Unlike CRP, which is manufactured predominatly in the liver, PTX3 is produced especially at sites of tissue damage. PTX3 synthesis is induced by proinflammatory cytokines TNF-α or IL-1β and by microbial wall constituents such as the lipololysaccharide (LPS). Plasma protein PTX3 concentrations are elevated in a wide range of diseased states, such as in coronary artery disease, in pulmonary infection and acute lung injury, 3 in patients with chronic kidney disease, in pacients with depression, during normal pregnancy and preeclampsia, in pacients with psoriasis and during cardiac surgery with or without cardiopulmonary bypass. PTX3 was detected using detection set (Alexis Biochemicals, Switzerland) cat.no. ALX- 850-299-KI01 for sandwich ELISA application that provided capture monoclonal antibody to PTX3, detection polyclonal antibody to PTX3 and recombinant PTX3 (standard). Goeckerman's therapy of psoriasis is highly efficient in...
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Prepsration of recombinant cDNA of drug transporters
Svobodová, Iveta ; Štaud, František (advisor) ; Červený, Lukáš (referee)
CDS for ABCC4 and ABCC5 transporters were amplified. For ABCC5 two systems were outlined, however the only first one was used. The optimal annealing temperature was 64 řC; optimal concentration of magnesium was 2mM. TOPO XL have proved best results in our research in between cloning kits we tried. The CDS for ABCC4 and ABCC5 were cloned into the vector. Inserts were rended with the use of restrictive endonucleasis. ABCC4 was gashed by Spe I and Not I and ABCC5 by EcoR I and Hind III. With the same endonucleasis, the process of rending was repeated for pZeoSV2(-). Afterwards, the inserts were cloned into pZeoSV2(-).
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