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Spontaneous calcium permeability of ionic channel of P2X receptor after substitution ofconserved tyrosine in the 1st transmembrae domajn
Rupert, Marian ; Zemková, Hana (advisor) ; Balík, Aleš (referee)
Purinergic receptors are membrane ion channels that are activated by extracellular ATP. In vertebrates, seven genes encode subunits of P2X receptors. The subunits, designated P2X1-7, are 40 - 50% identical in amino acid sequences. P2X receptors are composed of three subunits and are found as homo- and heterotrimers in tissues of vertebrates. P2X receptors have a wide distribution in the organism, functional receptors are found in neurons, glial cells, muscle cells and also in nonexcitable tissues as epithelial, endothelial, and in hemopoietic tissue. Purinergic signalling plays an important role in pain transmission, at CNS injury and immune processes. P2X receptor subunit consists of two transmembrane domains, extracellular domain and intracellular N-and C-termini. Each transmembrane domain contains two amino acids conserved across all P2X subunits. In the first transmembrane domain receptor P2X2 are that Gly30 and Tyr43. In previous experiments performed on P2X2 receptor, electrophysiological measurements demonstrated that substitution of conserved Tyr43 in the first transmembrane domain with alanine prolongs the deactivation time of ion channel after agonist wash out. This work is focused on clarifying the role of conserved tyrosine in the process of opening and closing of ion channel of P2X...
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Automatic train protections system tester
Marek, Michal ; Musil, Vladislav (referee) ; Šteffan, Pavel (advisor)
The Master´s thesis describes continuous automatic train protection system and its functional properties, principally the transmission of special encoded signal between stationary part and rail vehicle. There is also summarized some important information about the gear rotational speed sensors and its communication with other onboard peripherals. Depends by analysed parameters of electrical signals, the general suggestion of portable electronic device is outlined. Portable electronic device or TESTER will be used to in phase of testing mobile part of automatic train protection system mounted onboard of rail vehicle. Tester will generate equivalent electrical signals to signals in system automatic train protection and the real system response will be possible to evaluate. The generator block allows to model real electrical signals in automatic train protection technology type LS or type EVM and signals rail vehicle odometry.
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Characterization of phosphatases in tobacco plants (Nicotiana tabacum L.)
Růžičková, Kateřina ; Ryšlavá, Helena (advisor) ; Tichá, Marie (referee)
Phosphateses (EC 3.1.3.x) are a group of enzymes that hydrolyze phosphoesters. That way they affect the energetic metabolism of a cell and its regulation. Phosphatases that dephosphorylate proteins are an integral part of signaling pathways, stress responses and they modulate enzymatic activity. This thesis deals with the study of phosphatases obtained from tobacco leaves (Nicotiana tabacum, L.). Solution of enzymes was prepared by extraction in both acidic and alkaline buffers. Through the use of the chromogenic substrate pNP-phosphate it was determined that there is a higher phosphatase activity in the glycosylated fraction than in the fraction that did not bind to Con A Sepharose. The research of the ions effect on the phosphatase activity has determined that Mg2+ and Ca2+ show positive effect on the phosphatase activity while the effect of Co2+ and Mn2+ is inhibitory. The Zn2+ ions have shown no effect whatsoever. The glycosylated phosphatases also dephosphorylated low-weight-molecular substrates phosphoserine, ATP and glucose-6-phosphate. The research of protein phosphatase activity discovered the affinity to the substrate phosvitin, although neither to casein nor its tryptic cleaves. Detailed experiments have shown that the pH optima for all the substrates lie from pH 5 to 6. Glycosylated phosphatases...
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On the role of the first transmembrane domain in desensitization kinetics of the P2X4 receptor.
Kalasová, Ilona ; Zemková, Hana (advisor) ; Krůšek, Jan (referee)
Extracellular adenosin-5'-triphosphate (ATP) is an important signalling molecule. Cells of eukaryotic tissues release ATP and express responding purinergic receptors. Ionotropic P2X receptors are trimeric ion channels permeable for K+, Na+ and Ca2+ ions. Each subunit consists of two transmembrane domains (TM1 and TM2), an extracellular loop and intracellular N- and C- termini. The transmembrane region is formed by six helical domains. According to the known crystal structure of zfP2X4 receptor, TM1 helixes are oriented peripherally and stabilize TM2 helixes which form the ion gate. However, eletrophysiological studies revealed that TM1 might also participate in channel gating and forming of the ion pore in the open state. The aim of this work was to investigate the role of TM1 in the process of desensitization of rat P2X4 receptor using cystein-scanning mutagenesis. Mutation of two residues (in Asn32 and Tyr42) prolonged desensitization of P2X4 receptor. Moreover, experiments with a partial agonist α,β-methylenadenosin-5'-triphosphate (αβ-meATP) proved that conformation change of TM domains in the process of desensitization is independent on conformation change caused by an agonist binding. Conserved residue Tyr42 is located in the proximity of TM2 of neighbouring subunit. It probably interacts with Met336...
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The Issue of Returning of Competitive Tennis Players post Game Break
Nekolová, Barbora ; Kočíb, Tomáš (advisor) ; Velenský, Michael (referee)
Title: The Issue of Returning of Competitive Tennis Players post Game Break Objectives of work: The aim of my bachelor thesis is to determine the course of two professional tennis players'career in connection with its long-term interruption. Surveys the circumstances and psychical and physical condition of athletes efore, during and after a tennis pause. The reasons and effect of carem interruptions will be explore. Method: Will be used methods as narrative interview - annotated transcription technice, quantitative interview, analysis and comparison. Results: In this work have been identified three scientific questions, all managed to handle. The reset of the research is fanding that a pause in a professional tennis player career did not have a negative impact on personal life, while in both cases the impact was positive. Negatively impressed by thein performance, because no one in the interval of pause trained fully. After return to the tournaments both players met the targets set out to do with the coach. Key words: tennis, professional tennis player, ATP, performance, personal life, sports goals
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Selected microbial processes in a bioreactor
Klinková, Lucie ; doc.RNDr.Petr Zbořil, CSc. (referee) ; doc.Ing.Martin Mandl, CSc. (advisor)
This thesis focuses on the study of the influence of selected parameters on the course of microbial cultivation and evaluation of bioprocess. It is divided into two parts. The first part deals with the production of mutant forms of the protein cryptogein yeast Pichia pastoris. The theoretical part summarizes the findings of the yeast P. pastoris and its expression. It also deals with cryptogein that induces defense reactions in plants. In the experimental part was produced mutant cryptogein X24, in which the concentration of each fraction and the ability to transfer sterols. The second part of this thesis is focused on aerobic and anaerobic oxidation of elemental sulfur by Acidithiobacillus ferrooxidans. In the theoretical section, our knowledge on A. ferrooxidans, its metabolism and the importance of ATP in cell metabolism was summarized. In the experimental part, the above bioprocess was monitored using pH, biomass concentration, the rate of oxidation of elemental sulfur the cellular ATP content.
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The Demembranation as a Tool to Study a Movement and Physiology of Activation of Fish Spermatozoa
BLAŽKOVÁ, Jaroslava
The aim of the thesis was the summarization of information about the demembranation method as a means of study of the physiology of activation and motility of fish spermatozoa. A simple demonstration of the method is also presented. The demembranation of fish sperm is a method, in which cytoplasmic membrane (the phospholipid bilayer, which separate intercellular and extracellular environments) is destroyed. A mild non-ionic detergent, TrintonX-100, was used in the study. Common carp (Cyprinus carpio) as a representative member of Teleost fish and sterlet as a member of Chondrostean (elasmobranch) fish were studied in the thesis.
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Legal relations in transport of people and goods
REZKOVÁ, Ivana
This thesis revers to the Legal relations in transport of people and goods. The introducy chapters are described types of transports. The major part of this text is dedicated to the international and inland treaties. In the practical part of this thesis directs its attention at clarifying essential parts of Agreement ADR and shows the application of Agreement ADR.In the closing part the autor indicates the necessity for a collaborative development of contracting states in Agreement ADR.
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ATP content of fish spermatozoa
GAVENDA, Tomáš
In the present work we study the possibility of measurment ATP content in inactive fish sperm. The samples were measured after demembranation of the fish sperm using the method of chemiluminscence by luciferin-luciferase. Light emission was measured by TECAN Infinite 200 in the mode of luminscence. Content of ATP was calculated and amount of ATP in nM to 10 8 sperm cells is shown in the result of the work. For our work we chose Cyprinus carpio and Acipenser baeri as model organisms.
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