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The impact of synthetic chelators from the group of 4-acylpyrazole-5-ones on alcohol dehydrogenase
Sobolová, Zuzana ; Mladěnka, Přemysl (advisor) ; Jirkovský, Eduard (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Zuzana Sobolová Supervisor: Prof. Přemysl Mladěnka, Pharm.D., Ph.D. Consultant: Marcel Hrubša, MS.c. Title of diploma thesis: The impact of synthetic chelators from the group of 4-acylpyrazole-5-ones on alcohol dehydrogenase Inhibitors of alcohol dehydrogenase play a key role in the treatment of poisoning caused by methanol, ethanol, ethylene glycol, and their toxic metabolites. Such treatment can therefore be considered as life-saving. In clinical practice, a single substance, fomepizole, is used. This thesis is aimed at investigation of the effect of eleven experimental chelators from the 4- acylpyrazol-5-ones group on equine and yeast alcohol dehydrogenases, and the possible definition of structural features that would be the most suitable for interaction with this enzyme. Due to the ability of these substances to chelate zinc ions, it is believed that they could inhibit an enzyme that has a zinc molecule in the structure. The measurement itself is based on principle of increase in absorbance during the enzymatic reaction, which is caused by the formation of NADH. This measurement is relatively simple, efficient and, due to used kinetic method, also less susceptible to be affected by...
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Sulfates as phase II metabolites of natural phenolic compounds
Hetman, Anastasiia ; Mladěnka, Přemysl (advisor) ; Siatka, Tomáš (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Anastasiia Hetman Supervisor: Assoc. Prof. Přemysl Mladěnka, PharmD., Ph.D. Co-supervisor: Assoc. Prof. Kateřina Valentová, Ph.D. Title of diploma thesis: Sulfates as phase II metabolites of natural phenolic compounds Natural monophenolic compounds, which both occur in plants and are formed during gut microbiota metabolism of polyphenols, are absorbed and pass through phase II metabolism. This results in the formation of various conjugated metabolites, such as sulfates, whose biological activity was not studied as yet. This work focused on the preparation and isolation of pure sulfated metabolites of phenolic compounds, namely 4- methylcatechol, protocatechuic, homoprotocatechuic, and 2,3,4-trihydroxybenzoic acid, and phloroglucinol, using the aryl sulphotransferase from Desulfitobacterium hafniense. As a result, two sulfated products of sufficient purity were prepared, namely 4- methylcatechol-O-sulfate (an inseparable mixture of 4-methylcatechol-2-O-sulfate and 4- methylcatechol-1-O-sulfate) and phloroglucinol-O-sulfate. Their antioxidantactivity was evaluated and compared with the activity of the parent compounds using the following six in vitro tests: DPPH (1-diphenyl-2-picrylhydrazyl) and...
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Immobilization of protease V8 on magnetic particles for application to proteolytic cleavage of pepsin A
Čepa, Adam ; Pacáková, Věra (advisor) ; Tichá, Marie (referee)
This thesis is part of a long-standing research in the field of diagnosis of the stomach diseases, which is based on the gastric enzyme pepsin A mapping. It was found that a phosphorylation in the primary structure of this enzyme may serve as a marker of incipient stage of carcinogenesis. This thesis is focused on the immobilization of protease V8 isolated from microorganism Stafylococcus aureus to magnetic agarose beads. Protease V8 is a promising candidate for producing peptide maps of pepsin A. The influence of pH, temperature and reaction time on the enzyme to activity has been studied and the optimal conditions for hydrolytic catalysis of formation of peptide fragments of pepsin A.
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Preparation of Influenza Neuraminidase and Polymerase Inhibitors
Zima, Václav
Influenza is an infectious disease caused by the influenza virus. This virus causes a severe viral infection that spreads easily from person to person in yearly pandemics. Vaccination is the most effective way to prevent the infection, however, due to the high rate in mutations of the virus, the vaccine needs to be often reformulated. Another option to combat influenza is based on administration of antiviral drugs. Clinical studies of isolated influenza strains ("avian flu" H5N1, 2004; "swine flu" H1N1, 2009) revealed resistance towards known influenza neuraminidase inhibitors (zanamivir, oseltamivir). The resistance is caused by structural changes close to the enzymatic site. This calls for the development of new neuraminidase inhibitors as well for development of inhibitors targeting different influenza enzymes. This Thesis is focused on design and synthesis of new inhibitors of influenza neuraminidase and RNA-dependent RNA polymerase, namely PA subunit and the assembly of PA-PB1 heterodimer enzymes (Scheme 1). Influenza neuraminidase inhibitors were prepared by C-5 derivatization of oseltamivir followed by subsequent extension of its structure with binders of 150-cavity. Binding potencies of new oseltamivir derivatives against two influenza strains were determined. The next part contributed to...
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The impact of synthetic chelators from the group of 4-acylpyrazole-5-ones on alcohol dehydrogenase
Sobolová, Zuzana ; Mladěnka, Přemysl (advisor) ; Jirkovský, Eduard (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Zuzana Sobolová Supervisor: Prof. Přemysl Mladěnka, Pharm.D., Ph.D. Consultant: Marcel Hrubša, MS.c. Title of diploma thesis: The impact of synthetic chelators from the group of 4-acylpyrazole-5-ones on alcohol dehydrogenase Inhibitors of alcohol dehydrogenase play a key role in the treatment of poisoning caused by methanol, ethanol, ethylene glycol, and their toxic metabolites. Such treatment can therefore be considered as life-saving. In clinical practice, a single substance, fomepizole, is used. This thesis is aimed at investigation of the effect of eleven experimental chelators from the 4- acylpyrazol-5-ones group on equine and yeast alcohol dehydrogenases, and the possible definition of structural features that would be the most suitable for interaction with this enzyme. Due to the ability of these substances to chelate zinc ions, it is believed that they could inhibit an enzyme that has a zinc molecule in the structure. The measurement itself is based on principle of increase in absorbance during the enzymatic reaction, which is caused by the formation of NADH. This measurement is relatively simple, efficient and, due to used kinetic method, also less susceptible to be affected by...
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Preparation of Influenza Neuraminidase and Polymerase Inhibitors
Zima, Václav ; Machara, Aleš (advisor) ; Cibulka, Radek (referee) ; Soural, Miroslav (referee)
Influenza is an infectious disease caused by the influenza virus. This virus causes a severe viral infection that spreads easily from person to person in yearly pandemics. Vaccination is the most effective way to prevent the infection, however, due to the high rate in mutations of the virus, the vaccine needs to be often reformulated. Another option to combat influenza is based on administration of antiviral drugs. Clinical studies of isolated influenza strains ("avian flu" H5N1, 2004; "swine flu" H1N1, 2009) revealed resistance towards known influenza neuraminidase inhibitors (zanamivir, oseltamivir). The resistance is caused by structural changes close to the enzymatic site. This calls for the development of new neuraminidase inhibitors as well for development of inhibitors targeting different influenza enzymes. This Thesis is focused on design and synthesis of new inhibitors of influenza neuraminidase and RNA-dependent RNA polymerase, namely PA subunit and the assembly of PA-PB1 heterodimer enzymes (Scheme 1). Influenza neuraminidase inhibitors were prepared by C-5 derivatization of oseltamivir followed by subsequent extension of its structure with binders of 150-cavity. Binding potencies of new oseltamivir derivatives against two influenza strains were determined. The next part contributed to...
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Study of regulatory mechanisms of selected protein kinases
Petrvalská, Olívia
Through binding interactions with more than 300 binding partners, 14-3-3 proteins regulate large amount of biologically relevant processes, such as apoptosis, cell cycle progression, signal transduction or metabolic pathways. The research discussed in this dissertation thesis was focussed on investigating the role of 14-3-3 proteins in the regulation of two selected protein kinases ASK1 and CaMKK2. The main goal was to elucidate the mechanisms by which phosphorylation and 14-3-3 binding regulate functions of these protein kinases using various biochemical and biophysical methods, such as site-directed mutagenesis, enzyme activity measurements, analytical ultracentrifugation, small-angle X-ray scattering, chemical crosslinking, nuclear magnetic resonance and fluorescence spectroscopy. A structural model of the complex between the catalytic domain of protein kinase ASK1 with 14-3-3ζ, which was calculated using the small-angle X-ray scattering and chemical crosslinking data, suggested that this complex is conformationally heterogeneous in solution. This structural model together with data from time-resolved fluorescence and nuclear magnetic resonance suggested that the 14-3-3ζ protein interacts with the catalytic domain of ASK1 in the close vicinity of its active site, thus indicating that the complex...
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Tandemová hmotnostní spektrometrie sfingolipidů s aplikací pro metabolické studie a diagnostiku sfingolipidos
Kuchař, Ladislav
In recent years, mass spectrometry (MS) become the dominant technology in lipidomic analysis and widely influenced research and diagnosis of diseases of lipid metabolism, e.g. lysosomal storage disorders (LSD) characterized by impairment of the lysosomal functions. Defects in lysosomal processing of sphingolipids SFL belong to the category of sphingolipidoses. This condition has severe and even fatal clinical outcome. The primary aim of this work was to establish quantitative and qualitative methods of SFL analysis useful for research and diagnosis of LSD. At first, semisynthesis of mass labeled lipid standards utilizing immobilized sphingolipid ceramide N-deacylase was performed. Established methods of quantitative analysis were then used to prove the increased excretion of urinary SFL in LSD with characteristic storage in the kidney. Determination of excreted urinary SFL was found useful for differential diagnosis of prosaposin and saposin B deficiences for which routine enzymology is failing. MS also enabled monitoring of individual molecular species (isoforms) of SFL, which led to the finding that their urinary pattern is changing in some LSD. This resulted in the development of new screening method in dry urinary samples based on isoform profile evaluation. Another MS application referred to...
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Sulfates as phase II metabolites of natural phenolic compounds
Hetman, Anastasiia ; Mladěnka, Přemysl (advisor) ; Siatka, Tomáš (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Anastasiia Hetman Supervisor: Assoc. Prof. Přemysl Mladěnka, PharmD., Ph.D. Co-supervisor: Assoc. Prof. Kateřina Valentová, Ph.D. Title of diploma thesis: Sulfates as phase II metabolites of natural phenolic compounds Natural monophenolic compounds, which both occur in plants and are formed during gut microbiota metabolism of polyphenols, are absorbed and pass through phase II metabolism. This results in the formation of various conjugated metabolites, such as sulfates, whose biological activity was not studied as yet. This work focused on the preparation and isolation of pure sulfated metabolites of phenolic compounds, namely 4- methylcatechol, protocatechuic, homoprotocatechuic, and 2,3,4-trihydroxybenzoic acid, and phloroglucinol, using the aryl sulphotransferase from Desulfitobacterium hafniense. As a result, two sulfated products of sufficient purity were prepared, namely 4- methylcatechol-O-sulfate (an inseparable mixture of 4-methylcatechol-2-O-sulfate and 4- methylcatechol-1-O-sulfate) and phloroglucinol-O-sulfate. Their antioxidantactivity was evaluated and compared with the activity of the parent compounds using the following six in vitro tests: DPPH (1-diphenyl-2-picrylhydrazyl) and...
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