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Kartes, Bernd. "Der "Epitaphios" des Lysias /." Saarbrücken, 2000. http://catalogue.bnf.fr/ark:/12148/cb391758370.
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Gärtner, Martine. "Le fonctionnement du discours esclavagiste chez Lysias." Besançon, 1995. http://www.theses.fr/1995BESA1040.
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Loucks, Kathleen A. "Advocacy in the courts : narrative and argument in Lysias /." Thesis, Connect to this title online; UW restricted, 1994. http://hdl.handle.net/1773/8252.
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Vlachos, Basil P. "A critical and hermeneutical edition of Lysias XVII, XVIII, XIX." Thesis, University of Oxford, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.527403.
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Todd, Stephen Charles. "Athenian internal politics 403-395 B.C., with particular reference to the speeches of Lysias." Thesis, University of Cambridge, 1985. https://www.repository.cam.ac.uk/handle/1810/250871.
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Poupelin, Marie-Charlotte. "Forme et rôle de la religion chez les trois premiers orateurs attiques : Antiphon, Andocide et Lysias." Université Paris 4, 1985. http://www.theses.fr/1985PA040047.
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Soares, Fábio Augusto Morales. "A democracia ateniense pelo avesso: os metecos e a política dos discursos de Lísias." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/8/8138/tde-27042010-094630/.
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Esta dissertação consiste em uma investigação cujo objetivo é examir o tema da participação política dos metecos atenienses, através da análise dos discursos forenses de Lísias e da crítica da historiografia. Alguns conceitos são discutidos, como identidade, espaço, memória, Estado, vida cotidiana, reprodução social, poder, liberdade etc, como um meio de se acessar a complexidade da sociedade ateniense.This dissertation consists in a investigation which aims to examine the issue of the political participation of Athenian metic in Classical Athens, through the analysis of the Lysias forensic speeches and the critique of the historiography. Some concepts are discussed, like identity, space, memory, State, everyday life, social reproduction, power, freedom etc, as a way to have access to the complexity of Athenian society.
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Pontbriand, Ségolène de. "La résidence des Lysias à Europos-Doura (Syrie) et les grandes demeures urbaines privées au Proche-Orient, des Séleucides à l 'arrivée des Sassanides." Thesis, Paris 1, 2015. http://www.theses.fr/2015PA010635.
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Cette recherche est consacrée à la plus grande demeure privée du site d'Europos-Doura en Syrie, la résidence du gouverneur Lysias, stratège et épistate de la ville. Ce bâtiment, entièrement dégagé dans les années trente par la mission américano-française de l'Université de Yale, est resté à l'abandon durant un demi-siècle. En reprenant les travaux sur le site, la Mission Franco-Syrienne d'Europos-Doura a fait de la publication de cette résidence l'un de ses objectifs scientifiques. Le cadre historique de cette étude s'étend sur quatre siècles depuis la création de la ville vers 150 av. n. è. jusqu'à la prise de celle-ci par les Sassanides vers 256 de n. è. Première partie : l'histoire, les méthodes et les résultats de l'exploration archéologique du bâtiment par la Mission de Yale, puis la reprise de l'étude, à partir de 2006, en présentant les différents éléments d'analyse mis en place au cours de cette recherche. Deuxième partie : l'étude architecturale de la résidence de Lysias dans son dernier état présente les différents espaces et les éléments architecturaux qui la composent et permet également de déterminer des ensembles aux caractéristiques spécifiques. Troisième partie : l'évolution architecturale de la résidence à travers les différents états qu'elle a connus et la chronologie relative du bâtiment. Quatrième partie : comparaisons avec d'autres monuments semblables du site d'Europos-Doura et les grandes demeures de même période dans l'Orient hellénisé. Conclusion : la résidence de Lysias illustre le caractère particulier de l'architecture de prestige qui s'est développée à Europos-Doura, reflet d'une inspiration locale et de traditions gréco-mésopotamiennesThis research is dedicated to the largest private house of Europos-Dura in Syria, the Residence of the Governor Lysias, strategos and epistates of the city. This building has been excavated in the Thirties by the American-French expedition of Yale University and has remained abandoned during a half century. lt has never been published. The resumption of work by the French-Syrian expedition in Europos-Dura has made it as one of its scientific objectives. The historical context of this study spans four centuries since the creation of the city around 150 B. C. to the Sasanian siege and the death of the city circa 256 A. D. First part : history, methods and results of the archaeological excavations ofthis building by the Yale expedition and the resumption of the work since 2006, presenting the various elements and orientations of the study set up during this research. Second part : the architectural study of Lysias' Residence in its final state. A description of the different spaces and architectural elements that compose it allows us to identify sectors that have specific functions. Third part : the architectural evolution of the residence through the different states it has known and the relative chronology of the building. Fourth part : comparisons with other similar monuments of Europos-Dura and with other large dwellings of same period in the hellenized Orient. Conclusion : Lysias' Residence shows the uniqueness of the prestigious architecture that developed in Europos-Dura, which is a picture of a local inspiration and of Greco-Mesopotamian traditions
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Roth, Gaël Stéphane Wenceslas. "Nouvelles signalisations impliquant les lysines-méthyltransférases SMYD2 et SMYD3 dans le cancer Lysine methylation signaling in pancreatic cancer." Thesis, Université Grenoble Alpes, 2020. https://thares.univ-grenoble-alpes.fr/2020GRALV025.pdf.
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Les modifications post-traductionnelles des protéines sont impliquées dans un grand nombre de voies de signalisation physiologiques et sont essentielles au fonctionnement normal cellulaire. Leur dérégulation est impliquée dans de multiples processus pathologiques, et notamment dans la carcinogénèse. Les lysine-méthyltransférases SMYD2 et SMYD3 appartiennent à la famille des SET and MYND domain-containing protein (SMYD) et sont toutes deux surexprimées dans de nombreux cancers. Elles participent en effet à la régulation de multiples signalisations oncogéniques canoniques telles que la méthylation de p53 par SMYD2, ou la méthylation de VEGFR1 (vascular endothelial growth factor receptor 1), ou MAP3K2 (Mitogen-activated protein kinase kinase kinase 2) au sein de la voie Ras/Raf/Mek/Erk par SMYD3.Dans ce travail de thèse, nous avons identifié un certain nombre de substrats potentiels de SMYD2 et SMYD3 à partir de données issues d’approches protéomiques telles que le ProtoArray® et le SILAC-3xMBT pulldown couplé à la spectrométrie de masse. La première partie de cette thèse a consisté à produire et valider la méthylation des différents substrats candidats les plus prometteurs. Nous avons ainsi confirmé in vitro puis en cellules d’adénocarcinome pancréatique MIA PaCa-2, les évènements de monométhylation par SMYD2 de la protéine BCAR3 (Breast cancer anti-estrogen resistance 3) au niveau de sa lysine K334 -protéine impliquée dans l'agressivité et l’invasivité tumorale-, et de RTF1 (RNA polymerase-associated protein) au niveau de K587 -protéine appartenant au complexe PAF1-. De même, nous avons démontré la triméthylation de RNF113A (Ring Finger Protein 113A) K20 par SMYD3. La seconde partie de cette thèse a porté sur la caractérisation des conséquences phénotypiques de la triméthylation de RNF113A K20 dans un modèle de cancer pulmonaire à petites cellules. Nous avons démontré que la triméthylation de RNF113A bloque son interaction avec la phosphatase PP4. Cette perte d’interaction aboutit à une augmentation de son niveau de phosphorylation, entrainant une stimulation de son activité de E3-ubiquitine ligase impliquée dans la réponse aux dommages alkylants. La triméthylation de RNF113A par SMYD3 pourrait donc participer à la chimiorésistance des cellules tumorales aux agents alkylants.Ainsi, ce travail de thèse a permis d’identifier des nouvelles signalisations prometteuses impliquant SMYD2 et SMYD3, et plus particulièrement de mettre en évidence le rôle de SMYD3 dans la réparation de l’ADN suite à l’exposition aux agents alkylants par le biais de la méthylation de RNF113APost-translational modifications are involved in a large number of physiological signaling pathways and are essential for normal cellular functioning. Their deregulation is involved in multiple pathological processes, and particularly in carcinogenesis. The lysine methyltransferases SMYD2 and SMYD3 belong to the family of SET and MYND domain-containing proteins (SMYD) and are both overexpressed in many cancers. They participate in the regulation of multiple canonical oncogenic pathways via the methylation of substrates such as p53 by SMYD2, or VEGFR1 (vascular endothelial growth factor receptor 1), and MAP3K2 (Mitogen -activated protein kinase kinase kinase 2) within the Ras / Raf / Mek / Erk pathway by SMYD3.In this thesis work, using data from proteomic approaches without a priori such as ProtoArray® and SILAC-3xMBT pulldown coupled with mass spectrometry, we identified potential substrates of SMYD2 and SMYD3. The first part of this thesis consisted in the production of the most promising candidate substrates and the validation of their methylation. We confirmed in vitro and in MIA PaCa-2 pancreatic adenocarcinoma cells, the monomethylation by SMYD2 of the protein BCAR3 (Breast cancer anti-estrogen resistance 3) on its lysine K334 -protein involved in aggressiveness and tumor invasiveness-, and RTF1 (RNA polymerase-associated protein) on K587 -protein belonging to the PAF1- complex. Similarly, we demonstrated the trimethylation of RNF113A (Ring Finger Protein 113A) K20 by SMYD3. The second part of this thesis focused on the characterization of phenotypic consequences of RNF113A K20me3 in a small cell lung cancer model. We demonstrated that trimethylation of RNF113A repels its phosphatase PP4, leading to an increase of RNF113A phosphorylation. This induces an increase of its E3-ubiquitin ligase activity involved in DNA dealkylation repair by interacting with the ASCC complex (activating signal cointegrator 1 complex). The trimethylation of RNF113A by SMYD3 therefore participates in the chemoresistance of tumor cells to alkylating agents.This thesis work therefore made it possible to identify new promising signals involving SMYD2 and SMYD3, and to highlight the role of SMYD3 in DNA repair following exposure to alkylating agents through methylation of RNF113A
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El-Rayes, Waseem Mustafa. "A commentary on Plato's Lysis." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape9/PQDD_0020/MQ46972.pdf.
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Bordt, Michael Karl Eugen. "Ein Kommentar zu Platons Lysis." Thesis, University of Oxford, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339777.
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Foltz, Garrett. "Algae Lysis with Pulsed Electric Fields." DigitalCommons@CalPoly, 2012. https://digitalcommons.calpoly.edu/theses/732.
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With growing interest in alternative fuels, algae lipid harvesting is seen as a possible source of biofuel. Algae species under consideration include Chlorella vulgaris, Chlamydomonas reinhardtii and Dunaliella salina due to lipid contents as high as 30% to 56% of their dry weight (depending on growth conditions) and availability [5], [6]. In order to harvest lipids from algae, the cells must first be lysed.
Lysing is achieved by breaking the algal cell wall or membrane to separate oil from the rest of the algae biomass. Current lysing procedures use enzymes, pressure homogenization, and/or sonication to lyse cells; however, these methods are costly and complicate oil extraction [9], [10].
This project examines a novel method of cell lysis through pulsed electric field (PEF) application that enables cost-effective extraction methods relative to current enzyme and sonication techniques.
A theoretical model for cell membrane potential in the presence of electric field was developed, and PEF chambers were manufactured on microscope slides to enable microscope viewing and cell lysis recording during PEF application. Additionally, larger static chambers were created for testing higher volumes of algal solution. Electric field characteristics, such as pulse width, pulse number and magnitude, sufficient for lysis of Dunaliella salina and Chlorella vulgaris were found.
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Pickert, Janko. "Untersuchungen zur Bindung kontaktallergener Substanzen an nukleophile Aminosäureseitenketten." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2004. http://nbn-resolving.de/urn:nbn:de:swb:14-1104831124156-50838.
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In der heutigen Zeit sind ca. 4000 Verbindungen bekannt, denen die Fähigkeit nachgesagt wird, eine Kontaktallergie auslösen zu können. Die Entscheidung, ob ein Stoff hautsensibilisierende Eigenschaften besitzt, wird dabei meist auf der Grundlage von Beobachtungen am Menschen und/oder von tierexperimentellen Befunden getroffen. Bedingt durch den vermehrten Einsatz exotischer Pflanzen und neu entwickelter synthetischer Substanzen im Bereich der Kosmetikindustrie besteht der Bedarf an einer einfachen Methode zur Vorhersage des kontaktallergenen Potentials einer Verbindung. Als zentraler Schritt bei der Manifestierung einer Kontaktallergie wird die Bildung eines Hapten-Carrier-Komplexes aus dem niedermolekularen Kontaktallergen (Hapten) und Hautproteinen (Carrier) angesehen. Zur Abschätzung der Sensibilisierungsfähigkeit kann daher auch die Reaktivität der Substanz oder ihrer Metaboliten gegenüber Proteinen herangezogen werden. Im Rahmen dieser Arbeit werden neben dem bedeutenden Phytoekzematogen Tulipalin A die bisher wenig untersuchten kontaktallergenen Duftstoffe Geraniol, 7-Hydroxycitronellal, Benzaldehyd, Salicylaldehyd, Vanillin, Zimtaldehyd, a-Amyl-zimtaldehyd und Benzylcinnamat hinsichtlich ihrer Reaktivität gegenüber peptidgebundenen Aminosäuren untersucht. Verwendet werden für diese Modellversuche Hippuryl-Derivate und Acetyl-Derivate der Aminosäuren Lysin, Histidin, Arginin bzw. Cystein sowie zusätzlich Glutathion. Die dabei gewählten Bedingungen sollen eine Adaption an physiologische Gegebenheiten erlauben. Ziel ist es, zu klären, ob die mit diesen Modellversuchen zu gewinnenden Ergebnisse mit dem bekannten kontaktallergenen Potential der eingesetzten Haptene korrelieren und somit geeignet sind, die Sensibilisierungsfähigkeit einer Substanz vorherzusagen. Über Konjugationsprodukte von Kontaktallergenen mit Peptiden oder Proteinen ist in der Literatur sehr wenig bekannt. Daher ist es ein weiteres Ziel dieser Arbeit, individuelle Produkte der Reaktionen der kontaktallergenen Substanzen mit den nukleophilen Aminosäureseitenketten zu isolieren und zu charakterisieren, um so definierte Hapten-Carrier-Konjugate, die unter physiologisch relevanten Bedingungen entstehen können, zu beschreiben. Aufbauend auf den gefundenen Strukturen sollte es auch möglich sein, Hinweise auf eventuelle Reaktionsmechanismen zu erhalten.
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Hutton, Claire. "Cloning and evaluation of bacterial lysins for biotechnology applications." Thesis, University of Nottingham, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.287187.
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Morse, Rachel H. A. "NK cell-mediated lysis of human autologous oligodendrocytes." Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=31275.
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Although considered an autoimmune disease, the mechanisms underlying oligodendrocyte/myelin injury in multiple sclerosis (MS) remain to be established. The aim of this study was to evaluate the capacity and requirements for natural killer (NK) cells to induce cytotoxicity of autologous human adult central nervous system derived oligodendrocytes (OLs) as measured by cytotoxicity assays (51Cr release). Levels of cytotoxicity directed at either heterologous OLs or U251 glioma cell targets correlated with progressive enrichment for NK cells and were dependent on exposure of the NK cells to IL-2. We found that the IL-2 treated enriched NK cell preparations were capable of mediating significant cytotoxicity of autologous OLs. These results suggest IL-2 activated NK cells can induce autologous OL injury, bypassing putative protective effects of self-MHC class I molecules. The inflammatory milieu in MS lesions could provide conditions required for NK cell activation.
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Lin, Hongqiao. "Lysine oxidation by myeloperoxidase." Cleveland State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=csu1449833806.
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Oviedo, Michael Peter. "Plato's lysis and its influence on Kant and Aristotle." [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-3038.
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Bindon, Carol Ianthe. "Complement-mediated lysis by monoclonal antibodies for human therapy." Thesis, University of Cambridge, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.253842.
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Manangi, Megharaja K. "Chicken lysine [alpha]-ketoglutarate reductase (LKR) in different tissues and effects of graded levels of dietary lysine on LKR and lysine oxidation." Morgantown, W. Va. : [West Virginia University Libraries], 2000. http://etd.wvu.edu/templates/showETD.cfm?recnum=1734.
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Thesis (M.S.)--West Virginia University, 2000.Title from document title page. Document formatted into pages; contains viii, 92 p. : ill. Vita. Includes abstract. Includes bibliographical references.
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McCluskey, Kaley A. "How the lysine riboswitch folds." Thesis, University of St Andrews, 2015. http://hdl.handle.net/10023/8241.
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To respond to rapidly-changing stresses in their environment, bacterial cells must be able to sense a variety of chemical cues and respond to them by activating the relevant genes. The lysine riboswitch is a short RNA motif, located just upstream of a gene encoding a lysine biosynthesis protein, that suppresses the expression of that gene when sufficient lysine is present in the cell. It acts by binding a lysine monomer in a region called the aptamer, which in turn rearranges an adjacent domain called the expression platform, sequestering the ‘start' sequence of the gene and preventing it from being transcribed. In this thesis, the lysine riboswitch's ligand-binding transition is studied using single-molecule fluorescence microscopy, optical tweezers, and a hybrid optical force/fluorescence technique. Förster Resonance Energy Transfer (FRET) is used with a fluorescently-labeled aptamer to show that it has a previously-undescribed, partially-folded structural state with enhanced ligand affinity compared to the unfolded structure. The Mg²⁺ dependence of the transition between these states is shown to resolve existing debates in the literature about the sensitivity of the riboswitch. The kinetics of the folding transition are explored using FRET, optical force, and hybrid ‘Fleezers' to map the free energy landscape of ligand binding and show that the ligand itself promotes transitions into the aptamer's folded state, a so-called ‘induced fit' mechanism rare among riboswitches. Finally, high-resolution optical tweezers are used to explore the link between the aptamer's secondary structure (the sequence of paired nucleotides) and its tertiary structure (three-dimensional folding) to illuminate the role of ligand binding in gene regulation, which depends on the equilibrium between competing secondary structures. Hybrid biophysical techniques like optical force/fluorescence microscopy are shown to be indispensable for addressing all the states in the reaction pathways of complex biomolecules like riboswitches and for discriminating between multiple levels of structure formation and interaction with the environment. Not only do the results presented here shed light on the RNA folding problem, particularly the role of tertiary structure in determining the minimum-energy configuration of an RNA sequence, but they could have implications for biomedical research, as the lysine riboswitch has already been shown to be a potential target for next-generation antibiotics.
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Feller, Christian. "Systematic analysis of lysine acetyltransferases." Diss., Ludwig-Maximilians-Universität München, 2014. http://nbn-resolving.de/urn:nbn:de:bvb:19-182203.
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Lambert, S. F. "Lysine-DNA interactions in chromatin." Thesis, University of Cambridge, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.332194.
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Drysch, André. "Intrazelluläre Flussquantifizierung unter instationären Wachstumsbedingungen und Mischsubstratverwertung in Corynebacterium glutamicum." [S.l.] : [s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=970648219.
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Xu, Min. "Bacteriophage P1: a new paradigm for control of phage lysis." Texas A&M University, 2004. http://hdl.handle.net/1969.1/2734.
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The N-terminal hydrophobic domain of the phage P1 endolysin Lyz was found to facilitate the export of Lyz in a sec-dependent fashion, explaining the ability of Lyz to cause lysis of E.coli in the absence of the P1 holin. The N-terminal domain of Lyz is demonstrated to be both necessary and sufficient not only for export to the membrane but also for release into the periplasm of this endolysin. We propose that this unusual N-terminal domain functions as a "signal arrest- release" (SAR) sequence, which first directs the endolysin to the periplasm in membrane-tethered form and then allows it to be released as a soluble active enzyme in the periplasm.
To understand why release from the membrane is required for the physiological expression of the lytic activity of Lyz, we examined the role of its seven cysteine residues in the biogenesis of the active endolysin. The inactive, membrane-tethered and the active, soluble forms of Lyz differ in their pattern of intramolecular disulfide bonding. We conclude that the release of Lyz from the membrane leads to an intramolecular thiol-disulfide bond isomerization causing a dramatic conformational change in the Lyz protein. As a result, an active site cleft that is missing in nascent Lyz is generated in the mature form of the endolysin. Examination of the protein sequences of related bacteriophage endolysins suggests that the presence of an SAR sequence is not unique to Lyz.
Studies on holin and antiholin indicated that P1 encodes two holins, LydA and LydC. The antiholin LydB inhibits LydA by binding to it directly on the membrane.
All above results demonstrate a new paradigm for control of phage lysis, which is, upon depolarization of the membrane by holin function at a programmed time, endolysin is released from the bilayer leading to the immediate lysis of the host.
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Dodd, Ian Burwell. "The control of the Lysis-Lysogeny System of Coliphage 186 /." Title page, table of contents and summary only, 1992. http://web4.library.adelaide.edu.au/theses/09PH/09phd6389.pdf.
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Drager, Robert Gray. "Molecular cloning of spinach chloroplast DNA isolated by alkaline lysis." PDXScholar, 1987. https://pdxscholar.library.pdx.edu/open_access_etds/3747.
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Chloroplast genomes of land plants show conservation of structure and gene arrangement. The spinach chloroplast genome is comprised of a covalently closed. circular DNA molecule of 150 kilobases and is typical of these plants. Approximately 20% of the proteins found in the spinach chloroplast are encoded by the chloroplast genome and translated on chloroplast ribosomes. The remainder are encoded on chromosomes in the nucleus, translated on cytoplasmic ribosomes and transported into the chloroplast.
Spinach chloroplast DNA was isolated from crude 2 chloroplast preparations by a new method. Chloroplasts were lysed with alkaline sodium dodecyl sulfate, contaminating macromolecules precipitated with acidified potassium acetate and plastid DNA was purified by phenol:chloroform extraction and ethanol:ammonium acetate precipitation. The yield was approximately 50 ug chloroplast DNA per 100 grams leaf material. The DNA consisted of 10% circular molecules and 90% linear molecules.
The chloroplast DNA was digested with restriction enzyme PstI and the fragments were cloned into the plasmid vector pUC9. Several recombinant plasmids were isolated and the chloroplast DNA inserts identified. The recombinant plasmid pRD105 containing the PstI #5 fragment was subjected to further investigation. The ClaI restriction sites of the PstI #5 fragment were mapped and the insert was subcloned into the plasmid vector pGEM4, which bears bacteriophage SP6 and T7 RNA polymerase promoter sequences.
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Fatkins, David G. "N(EPSILON)-THIOACETYL-LYSINE AS A MULTIFACETED TOOL FOR ENZYMATIC PROTEIN LYSINE N(EPSILON)-DEACETYLATION." University of Akron / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=akron1185377018.
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Whitcombe, David Mark. "Molecular cloning and analysis of a β-1,3-glucanase from Arthrobacter luteus (Oerskovia xanthineolytica)." Thesis, University of Leicester, 1988. http://hdl.handle.net/2381/35179.
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Species of Arthrobacter luteus, also known as Oerskovia xanthineolytica, can utilise yeast cells as a growth substrate. This unusual ability is due to the secretion of a battery of hydrolytic enzymes which degrade the yeast cell wall and thus lyse the cells. Although many hydrolytic enzymes are important in the degradation of the yeast cell wall, the key activities are endo beta--l,3-glucanases. In order to characterise components of the yeast lytic system and the genetic organisation of this little-understood organism, a molecular cloning approach was adopted. Large clones expressing beta-1,3-glucanase were isolated from a library of A. luteus DNA constructed in the positive selection vector pKGW. By a combination of subcloning, restriction mapping and Southern analysis, it was determined that the clones contained virtually the same inserts. Additional subcloning, transposon mutagenesis, deletion mapping and nucleotide sequencing were used to identify at least one glucanase gene. The predicted protein product had a molecular weight of about 46 kD. When the gene was expressed in a number of in vivo and vitro systems including E. coli minicells and a Streptomyces coupled transcription/translation system, the protein observed had a similar molecular weight. Furthermore, when the protein was produced in E. coli and run on activity stained gels, the beta-glucanase activity co-migrated with the major glucanase of A. luteus. In addition the E. coli-produced glucanase had the ability to cause limited lysis of yeast.
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Codato, Roberta. "The role of the lysine Methyltransferase SMYD3 in cell differentiation and cell identity." Thesis, Sorbonne Paris Cité, 2018. http://www.theses.fr/2018USPCC284.
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Dans les cellules eucaryotes, des changements dynamiques de la chromatine en combinaison avec des facteurs de transcription spécifiques au tissu, régulent les programmes d'expression des gènes, qui sous-tendent la différenciation cellulaire. La différenciation des muscles squelettiques est principalement orchestrée par une famille de quatre facteurs de transcription de base hélice-boucle-hélice (bHLH): MyoD, Myf5, Myogenin et Mrf4. Les technologies de cartographie à l'échelle du génome ont révélé l'étendue du remodelage épigénétique dynamique soulignant la myogenèse. Plusieurs études ont porté sur le rôle des histones Lysine Méthyltransférases (KMT) et leur rôle dans la répression (H3K9 / H3K27) ou l'activation (H3K4) transcriptionnelle, et ont mis en évidence la fonction des modifications des histones dans la myogenèse et la régulation des gènes spécifiques des muscles. Nous avons étudié le rôle de la KMT SMYD3, qui est hautement conservé, au cours de la différenciation du muscle squelettique. Les membres de la famille des protéines SMYD sont impliqués dans la myogenèse cardiaque et squelettique au cours du développement chez le poisson-zèbre, la drosophile et la souris. SMYD3 est fréquemment surexprimé dans les cancers humains et des études ont mis en évidence un rôle potentiel de SMYD3 dans le développement précoce et la différenciation des cellules musculaires. Pourtant, le rôle de SMYD3 dans ces processus est encore un sujet de débat et d'investigation. Afin d'obtenir de nouvelles informations sur la régulation de la myogenèse par la famille SMYD de KMTs, nous avons examiné le rôle de SMYD3 dans la différenciation des myoblastes en utilisant un système in vitro de myoblastes humains et murins. Nos résultats d'expériences de gain et de perte de fonction suggèrent un rôle critique pour SMYD3 dans la régulation épigénétique de l'expression génique au cours de la différenciation musculaire. En particulier, l'inhibition de l'expression de SMYD3 entraîne une altération précoce de la différenciation musculaire et la fusion des myoblastes pour former des myotubes multinucléés. D'autre part, la surexpression de SMYD3 dans les myoblastes induit l'expression de marqueurs de différenciation spécifiques et améliore globalement le processus de différenciation. En utilisant des études de séquençage haut-débit de l’ARN, nous avons montré que SMYD3 régule les gènes impliqués dans l'organisation du sarcomère et le développement musculaire lors de la différenciation. De plus, nous avons trouvé par des études ChIP que SMYD3 se lie au promoteur de la Myogenin dans les myoblastes C2C12. En conclusion, nous avons révélé un nouveau mécanisme de régulation du facteur de différenciation clé Myogenin, et identifié un nouveau rôle pour SMYD3 dans la myogenèse squelettiqueIn eukaryotic cells, dynamic changes in chromatin architecture combined with tissue-specific transcription factors regulate the gene expression programs, which underlie lineage commitment and cell differentiation. Skeletal muscle differentiation is mainly orchestrated by a family of four basic-helix-loop-helix (bHLH) transcription factors: MyoD, Myf5, Myogenin and Mrf4. Genome-wide mapping technologies revealed the extent of dynamic epigenetic remodeling underlining myogenesis. Several studies have focused on the role of Histone Lysine Methyltransferases (KMT), and their role in transcriptional repression (H3K9/H3K27) or activation (H3K4), and highlighted the function of histone modifications in myogenesis and the regulation of muscle-specific genes. We studied the role of the highly conserved KMT SMYD3 during skeletal muscle differentiation. Members of the SMYD protein family are implicated in cardiac and skeletal myogenesis during development in zebrafish, Drosophila and mice. SMYD3 is frequently upregulated in human cancers and there are evidences supporting a role of SMYD3 in early development and muscle cell differentiation. Yet, the role of SMYD3 in these processes is still a matter of debate and investigation. To gain new insights into the regulation of myogenesis by the SMYD KMT family, we examined the role of SMYD3 on myoblasts differentiation by using an in vitro system of human and mouse myoblasts. Our results of gain- and loss-of-function experiments suggest a critical role for SMYD3 in epigenetic regulation of gene expression during muscle differentiation. In particular, inhibition of SMYD3 expression leads to an impairment in early muscle differentiation, and myoblasts fusion to form multinucleated myotubes. On the other hand, SMYD3 overexpression in myoblasts induces the expression of specific differentiation markers and globally enhances the differentiation process. By using RNA-seq studies, we showed that SMYD3 regulates genes involved in sarcomere organization and muscle development upon differentiation. Moreover, we found by ChIP studies that SMYD3 binds to the Myogenin promoter in C2C12 myoblasts. In conclusion, we revealed a novel mechanism of regulation of the key differentiation factor Myogenin, and identified a novel role for SMYD3 in skeletal myogenesis
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Kiess, Aaron S. "Hepatic [alpha]-aminoadipate [delta]-semialdehyde synthase appears to be post-translationally regulated in mouse and chicken." Morgantown, W. Va. : [West Virginia University Libraries], 2006. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=4770.
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Thesis (Ph. D.)--West Virginia University, 2006.Title from document title page. Document formatted into pages; contains vii, 105 p. : ill. Vita. Includes abstract. Includes bibliographical references.
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Warren, Kristin M. "Passive Mechanical Lysis of Bioinspired Systems: Computational Modeling and Microfluidic Experiments." Research Showcase @ CMU, 2016. http://repository.cmu.edu/dissertations/840.
Full textAbstract:
Many developed nations depend on oil for the production of gasoline, diesel, and natural gas. Meanwhile, oil shortages progress and bottlenecks in oil productions continue to materialize. These and other factors result in an energy crisis, which cause detrimental social and economic effects. Because of the impending energy crisis, various potential energy sources have developed including solar, wind, hydroelectric, nuclear, and biomass. Within the biomass sector for renewable energy sources, algae-based biofuels have become one of the most exciting, new feedstocks. Of the potential plant biofuel feedstocks, microalgae is attractive in comparison to other crops because it is versatile and doesn’t pose a threat to food sources. Despite its many advantages, the process to convert the microalgae into a biofuel is very complex and inefficient. All steps within the algae to biofuel production line must be optimized for microalgal biofuel to be sustainable. The production of biofuels from algae begins with selecting and cultivating an algae strain and giving it all the necessities to grow. The algae is then harvested and processed for specific uses. It is the harvesting or lysing step, which includes the extraction of the algal lipids, which is the biggest hindrance of algae being used as a cost effective energy source. The lysing step within the microalgal biofuel processing is of particular interest and will be the focus of this work. This work discusses the optimization of the biofuel production from microalgae biomass through computational and experimental approaches. With atomic force microscopy (AFM), a key mechanical property that would aid in the computational modeling of mechanical lysis in the in-house computational fluid dynamics (CFD) code, Particle-Surface Analysis Code (P-STAC), was determined. In P-STAC, various flow patterns were modeled that would most effectively lyse microalgal cells based on the shear stresses placed on the cells, which will be compared against microfluidic experiments using lipid specific dyes. These results would be influential in developing an energy-efficient method of processing microalgae for biofuel.
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La, Gioia Alessandra. "Optimisation of chemical lysis protocol for point-of-care leukocyte differentiation." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amslaurea.unibo.it/7270/.
Full textAbstract:
The full blood cell (FBC) count is the most common indicator of diseases. At present hematology analyzers are used for the blood cell characterization, but, recently, there has been interest in using techniques that take advantage of microscale devices and intrinsic properties of cells for increased automation and decreased cost. Microfluidic technologies offer solutions to handling and processing small volumes of blood (2-50 uL taken by finger prick) for point-of-care(PoC) applications. Several PoC blood analyzers are in use and may have applications in the fields of telemedicine, out patient monitoring and medical care in resource limited settings. They have the advantage to be easy to move and much cheaper than traditional analyzers, which require bulky instruments and consume large amount of reagents. The development of miniaturized point-of-care diagnostic tests may be enabled by chip-based technologies for cell separation and sorting. Many current diagnostic tests depend on fractionated blood components: plasma, red blood cells (RBCs), white blood cells (WBCs), and platelets.
Specifically, white blood cell differentiation and counting provide valuable information for diagnostic purposes. For example, a low number of WBCs, called leukopenia, may be an indicator of bone marrow deficiency or failure, collagen-
vascular diseases, disease of the liver or spleen. The leukocytosis, a high number of WBCs, may be due to anemia, infectious diseases, leukemia or tissue damage. In the laboratory of hybrid biodevices, at the University of Southampton,it was developed a functioning micro impedance cytometer technology for WBC differentiation and counting. It is capable to classify cells and particles on the base of their dielectric properties, in addition to their size, without the need of labeling, in a flow format similar to that of a traditional flow cytometer. It was demonstrated that the micro impedance cytometer system can detect and differentiate monocytes, neutrophils and lymphocytes, which are the three major human leukocyte populations. The simplicity and portability of the microfluidic impedance chip offer a range of potential applications in cell analysis including point-of-care diagnostic systems. The microfluidic device has been integrated into a sample preparation cartridge that semi-automatically performs erythrocyte lysis before leukocyte analysis. Generally erythrocytes are manually lysed according to a specific chemical lysis protocol, but this process has been automated in the cartridge. In this research work the chemical lysis protocol, defined in the patent US 5155044 A, was optimized in order to improve white blood cell differentiation and count performed by the integrated cartridge.
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Moura, Heleniara Amorim. "Passagens da memória: ensaio biográfico sobre a artista Lysia de Araújo." Universidade Federal de Minas Gerais, 2015. http://hdl.handle.net/1843/ECAP-9UVGHG.
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This work is a biographical essay about the actress and writer Maria Lysia Correa de Araujo (1921-2012) who produced a diverse literature, presenting a set of literary composition (in a variety of) genres such as theater critics, chronic, novel and short stories. This artist was often inserted in the (critical) aesthetics called fantastic realism or magical realism and her production is part of the Brazilian disturbed postmodernism context from the 50s, 60s and 70s XX century, at this moment it brings out a production close to the next generation of Spanish American literature in the country, which is contemporary, written surrounded by authoritarian and violent governments. Furthermore, as an actress, she was present at expressive art assemblies and the School of Dramatic Art of São Paulo awarded her. In her artistic life, she lived for a short time in various cities like São Paulo, Rio de Janeiro, Recife and Belo Horizonte participating in important theater groups such as Arena, Oficina, Cia Maria Della Costa, Cia Tônia Autran, among others. She worked with directors like José Celso Martinez, Augusto Boal, Alfredo Mesquita, while enacting pieces of deep ideological content in a period of silence and repression. Through a methodology straddles the concept of Benjamin in 'Passagen-werk', the faces of the fragment, quote, the remains, finally, a whole range of residual invests biographical material to the possibility of formation of a life story. From this set, we intend to conduct a biographical essay that can encompass multiple facets of the artist's existence, also extending it to a heterobiography memory, which allows us to understand the biographical spaces in which it takes the existence of Lysia de Araújo, her art and her writingEste trabalho é um ensaio biográfico sobre a atriz e escritora mineira Maria Lysia Corrêa de Araújo (1921-2012) que produziu uma literatura diversificada, apresentando um conjunto de composição literária em variados gêneros como a crítica teatral, a crônica, o romance e o conto. A artista foi frequentemente inserida pela crítica na estética do chamado realismo fantástico ou realismo mágico e sua produção insere-se no contexto brasileiro de uma conturbada pós-modernidade das décadas de 50, 60 e 70 do século XX, momento que faz aflorar no país uma produção próxima da literatura hispano-americana que lhe é contemporânea, escritas circundadas por governos autoritários e violentos. Além disso, como atriz, esteve presente em montagens expressivas à época, sendo premiada pela Escola de Arte Dramática de São Paulo. Em sua vida artística, itinerou por várias cidades como São Paulo, Rio de Janeiro, Recife e Belo Horizonte participando de grupos teatrais importantes como o Arena, o Oficina, a Cia Maria-Della Costa, a Cia. Tônia-Autran, entre outras. Trabalhou com diretores como José Celso Martinez, Augusto Boal, Alfredo Mesquita, além de encenar peças de conteúdos ideológicos profundos em uma época de silenciamento e repressão. Através de uma metodologia atravessada pelo conceito das passagens benjaminianas, as fisionomias do fragmento, das citações, dos resquícios, enfim, toda uma gama do residual investe ao material biográfico a possibilidade de constituição da história de uma vida. A partir desse conjunto, pretende-se realizar um ensaio biográfico que possa abarcar as facetas múltiplas da existência da artista, estendendo-a também a uma memória heterobiográfica, que possibilite compreender os espaços biográficos nos quais se insere a existência de Lysia de Araújo, sua arte e sua escrita
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Nixey, Clifford. "The lysine response of the turkey." Thesis, University of Nottingham, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.292721.
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Gerken, Philip. "Chemical probes for histone lysine demethylases." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:8d98e1d6-6a79-4fbc-a04b-776179225498.
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The primary objective of this DPhil research project was to develop selective and cell-active inhibitors of the histone lysine demethylase KDM2A, which could potentially lead to the discovery of a novel chemical probe. Chapter one of this thesis introduces the role of histone lysine demethylases (KDMs) in the epigenetic regulation of gene expression and discusses the value of chemical probes as tools to study these enzymes. Chapter two describes the synthesis of a library of indoline-based KDM2A inhibitors using a modular synthetic approach to explore key structure-activity relationships and a chiral counterion-mediated strategy to synthesize lead candidates enantioselectively. Chapter three discusses investigations into the cellular activity of lead compounds and explores strategies to address limitations associated with cytotoxicity and promiscuity. Chapter four describes the application of a variety of experimental techniques to identify the mode of target inhibition. Finally, chapter five focuses on the development of an enantioselective C-acylation reaction to access spirocyclic fragments asymmetrically.
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Hauser, Anett. "Chemical Approaches to Elucidate Lysine Phosphorylation." Doctoral thesis, Humboldt-Universität zu Berlin, 2021. http://dx.doi.org/10.18452/22287.
Full textAbstract:
Reversible Phosphorylierung ist die bekannteste posttranslationale Modifikation (PTM) und die O-Phosphomonoester von Serin, Threonin und Tyrosin galten lange als die einzigen relevanten Vertreter. Vor kurzem wurden erste Erkenntnisse über die biologische Relevanz von labilen Phosphorylierungen veröffentlicht, z.B. die Phosphorylierung von Histidin, Arginin und Cystein sowie die Pyrophosphorylierung von Serin und Threonin. Auch die Aufklärung von Phospho-Lysin (pLys) wurde mit der Etablierung einer chemoselektiven Synthese zur Darstellung ortsselektiv phosphorylierter Lysinpeptide und der Entwicklung massenspektrometrischer Protokolle zur eindeutigen pLys-Identifizierung in Angriff genommen. Dennoch wurde bisher kein endogenes pLys beschrieben oder eingehende Untersuchungen mit interagierenden Enzymen durchgeführt.
In dieser Arbeit werden mehrere Ansätze zur Erweiterung des Wissens über pLys vorgestellt. Dazu gehören das Design einer alternativen Syntheseroute zu pLys-Peptiden und die Entwicklung sowie Evaluierung von zwei stabilen Analoga als Bausteine für die Peptidsynthese. Weiterhin wurde die Protonierung des Phosphoramidatstickstoffs untersucht. In systematischen Enzymaktivitätsassays wurden die Wechselwirkungen zwischen Phospholysine phosphohistidine inorganic pyrophosphate phosphatase (LHPP) und verschiedenen Phospho-Substraten untersucht. Dabei zeigte sich eine ausgeprägte Selektivität für pLys, eine hohe Sequenzabhängigkeit der LHPP-Aktivität und ein klares Bindungsmotiv. Darüber hinaus wurden proteomische Methoden hinsichtlich ihrer Eignung für pLys-Peptide evaluiert. Im Laufe dieser Untersuchung wurden mehrere pLys-Immunogene für die Generierung von monoklonalen anti-pLys-Antikörpern und ein Workflow für die Histontrennung und -analyse entwickelt. Des Weiteren wurde die chelationsverstärkte Fluoreszenz von markierten Phospho-Peptiden als Werkzeug zur Bestimmung des Phosphorylierungsgrades in Enzymaktivitäts- oder Stabilitätsassays untersucht.Reversible phosphorylation is the most prominent post-translational modification (PTM) and the O-phosphomonoesters of serine, threonine and tyrosine have been considered as the only notable forms for long time. Recent developments have paved the way to insights into the biological relevance of labile phosphorylations, e.g. phosphorylation of histidine, arginine and cysteine as well as pyrophosphorylation of serine and threonine. Also, the elucidation of phospho-lysine (pLys) was tackled with the establishment of a chemoselective synthesis to obtain site-selectively phosphorylated lysine peptides and the development of mass spectrometric protocols to unambiguously identify modification sites. Nonetheless, no endogenous pLys site has been described or in-depth investigations of interacting enzymes have been conducted. In this thesis, several approaches to enhance the knowledge about pLys are introduced. These include the design of an alternative synthesis route to pLys peptides and the development as well as evaluation of two stable analogues as building blocks for peptide synthesis. Furthermore, the protonation of the phosphoramidate-nitrogen was investigated. In systematic phosphoramidate hydrolase and phosphatase activity assays, the interactions between phospholysine phosphohistidine inorganic pyrophosphate phosphatase (LHPP) and various phospho-substrates were examined. Thereby, distinct selectivity for pLys, high sequence dependence of LHPP activity and a distinct binding motif were revealed. In addition to that, proteomic methods were evaluated regarding their suitability for pLys peptides. Over the course of this investigation, several pLys immunogens for the generation of monoclonal anti-pLys antibodies and a workflow for histone separation and analysis were developed. Furthermore, chelation-enhanced fluorescence of labeled phospho-peptides was studied as a tool for determining the degree of phosphorylation in enzyme activity or stability assays.
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Wang, Anita Wen Tao. "Loss of lysine in plant foods." Thesis, The University of Sydney, 2004. https://hdl.handle.net/2123/27713.
Full textAbstract:
Humans obtain approximately 70% of their dietary protein from plant sources on a
global basis. In developing countries, vegetable protein intake is higher than in
developed countries (Lusas and Rhee, 1986). Cereals, pulses and oilseeds are not
only very important plant foods in the human diet, but also the main components of
feeds for livestock, which can be considered as source of dairy products and meat
for humans (Lasztity and Hidvegi, 1983). Cereals contribute the major dietary
source of carbohydrates, and a substantive source of protein, vitamins, and
minerals. Oilseeds are one of the main sources of lipid, and pulses supply protein
and / or lipid. In many countries, including developed and developing countries,
wheat products are consumed as a major component of the diet. Wheat flour is one
of the most important foods in many countries in the world. Wheat grain contains
6-20% protein, 63-77% starch, approximately 2% fat, 2.0-2.7% crude fiber and
1.4-2.0% ash, depending in part on variety and class, and on environmental
conditions during growth (Pomeranz, 1988). In many Asian countries, rice is the
main cereal in the diet.
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Grice, Guinevere. "Decoding lysine-11 signals in ubiquitination." Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/274879.
Full textAbstract:
The diverse outcomes of ubiquitination primarily relate to the flexibility of ubiquitin in forming homo- or heterotypic chains on each of its seven lysine residues which in turn stimulate distinct downstream signaling pathways. These ubiquitin signals must be selectively initiated on the substrate protein and subsequently decoded to facilitate the desired cellular function. These initiation and decoding steps often involve additional post-translational modifications and ubiquitin receptor proteins, but the enzymes and ubiquitin chains involved for many ubiquitinated substrates are not clear. Here, I have explored the initiation and decoding of ubiquitin signals, focusing on lysine-11 (K11) linked polyubiquitin chains and their role in protein degradation. I established in vitro assays to understand how K11-chains are decoded and whether these chains act as a signal for proteasome-mediated degradation. Pure homotypic K11-chains did not bind the proteasome or its associated ubiquitin binding proteins, but did bind to the mitophagy ubiquitin receptors, MyosinVI and TAX1BP1. Heterotypic K11/K48 linkages not only bound the proteasome but also stimulated degradation of the cell cycle substrate, cyclin B1. To further explore the functions of K11-chains I focused on the hypoxia inducible transcription factor (HIF) pathway, as K11-ubiquitination had been implicated in proteasome-independent degradation of the transcription factor. I established an in vitro assay to initiate HIF ubiquitination, via prolyl hydroxylation, and determine the type of ubiquitin chains involved. Recombinant HIF isoforms were rapidly hydroxylated when incubated with cell extracts. Moreover, the levels of iron and small molecule metabolites within the lysates regulated HIF hydroxylation. However, this hydroxylation was insufficient to reproducibly promote HIF ubiquitination or determine the ubiquitin chains involved. While the nature of the polyubiquitin chains formed in the HIF pathway remain elusive, my studies identify distinct roles for homotypic and heterotypic K11-polyubiquitination in proteasome-mediated degradation.
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Zeman, Jan. "Studium interakcí polyelektrolytů s kladně nabitými dusíkatými amfifilními látkami." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2013. http://www.nusl.cz/ntk/nusl-216955.
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The study deals with interactions of polyelectrolytes polystyrene sulfonate and hyaluronic acid with nitrogenic amphiphilic substances, represented by lysine and albumine. To study the interactions pH-metry, conductance, viscositic and turbidity measurement, DLS and reometry were used. All mixtures of different concentrations were measured and the data were compered with data obtained from measurement of samples with amphiphilic sumstances without polyelectrolytes. Observed interactions occured in the aminoacid concentrations between 0 to 20 mmoldm-3, then the PSS interaction groups were fully bonded by lysine and no more interactions were recognized. The same behaviour were observed in albumine solutions with concentration under 2 gdm-3.
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Moir, Elaine. "The pro- and anti-fibrinolytic properties of human leucocytes." Thesis, University of Aberdeen, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340602.
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Takei, Jiro. "Structural and functional studies of membrane peptides : Glycophorin A transmembrane domain and melittin analogues." Thesis, University of Bristol, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.262734.
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Wang, Yi, and 王毅. "Structural basis on human Sirt6 function of hydrolyzing long chain fatty acyl lysine." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hdl.handle.net/10722/196481.
Full textAbstract:
Sirtuins, a class of enzymes known as nicotinamide adenine
dinucleotide-dependent deacetylases, have been shown to regulate a variety of biological processes, including aging, transcription, and metabolism. Severn human Sirtuins members (Sirt1-7) are involved in various kinds of severe diseases like aging, cancer development, autoimmune diseases and therefore are considered as potential drug targets for treatment. Among them, Sirt4-7 have very weak traditional deacetylation function in contrast to the others. So, investigation on the real functions of these sirtuins is a prerequisite for specific modulator (inhibitor or activator) design. Crystallography is a robust way to study the molecular basis of the catalytic function of these sirtuins. Here we show that the real function of Sirt6 is the de-long-chain-fatty acylase activity from lysine, such as the demyristoylase activity. The crystal structure of Sirt6 complex shows a large hydrophobic pocket accommodating the myristoyl group. Together with the biochemical and physiological data from our collaborators, we confirm that Sirt6 promotes the TNFα secretion via hydrolysis the myristoyl group on K19 and K20. Fatty acylation on lysine occurs in mammalian cells and had been found for years, however, the regulatory mechanism is still unclear. Our results provide the opportunities to understand the regulatory of the long chain fatty acyl modification on lysine via Sirt6, which has been little studied until now. More work will be focused on the structural based development of inhibitors to cure the Sirt6 regulated diseases in the near future.published_or_final_version
Physiology
Doctoral
Doctor of Philosophy
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Myint-Sein. "Études cinétiques et modélisation de la fermentation de lysine par Corynebacterium glutamicum." Vandoeuvre-les-Nancy, INPL, 1988. http://www.theses.fr/1988NAN10193.
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Hirsch, Brett M. "Mechanism-Based Peptidic and Peptidomimetic Human Sirtuin Inhibitors." University of Akron / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=akron1302055499.
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Boltz, Achim [Verfasser], and Harald [Akademischer Betreuer] Kolmar. "Bi-specific Aptamers mediating Tumour Cell Lysis / Achim Boltz. Betreuer: Harald Kolmar." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2011. http://d-nb.info/1105386902/34.
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Nývlt, Pavel. "Lýsiova řeč proti Eratosthenovi. Překlad, komentář a úvodní studie." Master's thesis, 2011. http://www.nusl.cz/ntk/nusl-296375.
Full textAbstract:
Lysias' speech Against Eratosthenes is the most famous speech of Lysias, Athen's most prolific author of lawcourt speeches. It deals with a murder of Lysias' brother Polemarchus, who was arrested and executed under the rule of so-called "Thirty Tyrants" in 404 B. C. And yet the topics covered are much wider, the speech thereby becoming a portrayal of the darkest times athenian democracy ever witnessed and a valuable document of democratic point of view on the events. The speech is commented from a historical point of view, focusing in the first place on political history and history of law.
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Swanson, Pascale Libront. "Revisiting the antifibrinolytic effect of carboxypeptidase N: novel structure and regulation." Master's thesis, 2010. http://hdl.handle.net/10048/1215.
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Carboxypeptidase N (CPN) is a plasma carboxypeptidase that was discovered in the 1960s as a regulator of inflammation and vascular tone. Through the removal of carboxy-terminal basic residues, CPN alters the activity or binding specificity of inflammatory mediators and vasoactive peptides. CPN shares significant homology with carboxypeptidases known to mediate antifibrinolysis through the removal of basic residues from fibrin clots, which would otherwise stimulate fibrinolysis. Despite the similarity of these enzymes, CPN is generally regarded as lacking a role in fibrinolysis. This thesis demonstrates that CPN is indeed a capable antifibrinolytic enzyme, and that the antifibrinolytic activity of CPN was previously undisclosed due to the presence of a circulating CPN inhibitor, which is likely the free CPN2 subunit. This inhibitor is described for the first time here. Furthermore, potential mechanisms of inhibition and mechanisms of enhancing activity of CPN are proposed based upon the additional structural characterization of CPN presented here.
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Tran, Tram Anh Thi. "Bacteriophage T4 lysis and lysis inhibition: molecular basis of an ancient story." 2007. http://hdl.handle.net/1969.1/ETD-TAMU-1241.
Full textAbstract:
T4 requires two proteins: holin, T (lesion formation and lysis timing) and
endolysin, E (cell wall degradation) to lyse the host at the end of its life cycle. E is a
cytoplasmic protein that sequestered away from its substrate, but the inner membrane
lesion formed by T allows E to gain access to the cell wall. T4 exhibits lysis inhibition
(LIN), a phenomenon in which a second T4 infection occurs ≤ 3 min after primary
infection results a delay in lysis. Mutations that abolish LIN mapped to several genes
but only rV encoding the holin, T, and rI, encoding the antiholin, RI, are required for
LIN in all hosts which support T4 replication. Antiholin RI inhibits T-mediated lysis by
direct interaction with the holin. T has at least one transmembrane domain with its Nterminus
(TNTD) in the cytoplasm and C-terminus in the periplasm (TCTD). In contrast,
the N-terminus of RI (RINTD) is predicted to function as a cleavable signal sequence
allowing the secretion of the RI C-terminal domain (RICTD) into the periplasm. Most of
RI mutations which abolish LIN occur in the RICTD, suggesting RI inhibits T-mediated
lysis by interacting with T via RICTD. Topological analysis of RI and T showed that fusion of PhoA signal sequence (ssPhoA) to RICTD is necessary and sufficient for LIN
and ssPhoAΦTCTD interferes with RI-mediated LIN, indicating T and RI interact via
periplasmic C-terminal domains.
In T4 infection, LIN is observed only when superinfection takes place, indicating
either the antiholin or the LIN signal must be unstable. Both RI and RINTDΦPhoA are
localized to both the inner membrane and the periplasm suggesting that the RINTD is a
Signal-Anchor-Release (SAR) domain. Protein stability studies indicated that the SAR
domain is the proteolytic determinant of RI, and DegP is the protease that is responsible
for RI degradation.
To date, how TNTD participates in lysis and LIN is not known. Modifications and
deletion of the N-terminus of T change the lysis time, indicating this domain is involved
the in timing of lysis. GFP fusion to holin T allowed microscopic visualization of
fluorescent patches on the membrane at the time of lysis.
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McIntosh, Brenley Kathleen. "Bacteriophage ms2 l protein: genetic and biochemical characterization." Thesis, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-2764.
Full textAbstract:
In order to release progeny, bacteriophages must lyse the host cell by compromising the peptidoglycan layer. There are two known strategies of lysis: the holin-endolysin system and single gene lysis (SGL), which are dependent on the genome size. Large phages encode multiple proteins, including a holin and endolysin, for lysis. In contrast, small ssRNA phages (Leviviridae and Alloleviviridae) and ssDNA phages (Microviridae) do not encode a muralytic enzyme and accomplish lysis with a single gene. The cellular target of the lysis gene E from the prototypic microvirus, φX174, and A2 from the prototypic allolevivirus, Qβ, has been elucidated. In both cases, these proteins were demonstrated to inhibit specific enzymes within the peptidoglycan biosynthetic pathway and infected cells lyse as a result of septal catastrophes. The prototype Levivirus MS2 encodes L, a 75 aa polypeptide that effects lysis without inhibiting murein synthesis. The purpose of the work described in this dissertation was to characterize MS2 L using genetic and biochemical strategies. Using a genetic approach, PcnB was shown to be important to the entry of the MS2 RNA into the cytoplasm. L accumulation during infection was quantified by comparison to purified, oligohistidine-tagged L. Biochemical experiments demonstrated the L protein behaved as a periplasmic, membrane-associated protein. The morphologies of cells undergoing L-mediated lysis are significantly different from cells lysing due to A2 expression, since L-lysing cells do not show septally localized membrane protrusions.
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Nai-AnWang and 王乃安. "Study of Blood Lysis by Irreversible Electroporation." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/py832c.
Full textAbstract:
碩士國立成功大學
工程科學系
102
SUMMARY This thesis presents an irreversible electroporation system for red blood cell lysis. The microchip device and three types of microelectrodes were designed and fabricated using MEMS and microfluidic technology. After integrating two different electrodes, we simulated and analyzed the suitable electric field for cell lysis by a finite element software, ANSYS, and found that when the parallel plate electrodes was at 5V, a notable lysis rate 95% was achieved in 10 seconds. Therefore, the proposed system has the advantage of less lysis time and higher lysis rate. Key words: cell lysis, electroporation, MEMS, glycated hemoglobin, biomedical sensor, microfluidic chip INTRODUCTION As the increased the number of patients with diabetes, market of blood glucose testing grows 10.7% every year. For example, glycosylated hemoglobin (HbA1c), the combination of HbA with glucose, is used for detecting diabetes or controlling blood glucose level. But, because hemoglobin and HbA1c are present in the red blood cells (RBC), cell lysis is required before detection. A common way to lyse cells is to use a lysis buffer, but the procedure is complicated and time-consuming. If the electric field intensity exceeds a critical value, the cell membrane becomes permeable to release the subcellular materials. In our study, we lysed RBCs by electroporation, which has the advantages of easy power supply, simple operation, and less chemical reactions. MATERIALS AND METHODS The electrodes was made of indium tin oxide, which has high electrical conductivity. Our three chips include a planar electrode chip, a parallel plate electrode chip and a microfluidic chip. The planar electrode chip was packaged by double-sided tape (30 μm in thickness), and the reaction region was 10 ×12 mm. Inside the planar electrode chip were 5000 micro electrodes categorized into three types: square, saw-tooth, and comb. The gap between the electrodes was 50 μm, and each electrodes generated a corresponding electric field. Then, the parallel plate electrode chip was also packaged by double-sided tape (200 μm in thickness), and the reaction region was 5 ×5 mm. In the microfluidic chips, two types of electrodes were integrated by surface modification and capillarity, and an electric field was generated between the upper electrode and the lower electrode. So that the cell lysis could be easily observed and measured. ANSYS 13.0 software was used to analyze the model of the chips and the distribution and intensity of the electric field to ensure its sufficient intensity. Function generator and high voltage amplifier were used to generate square pulses signal to lyse the RBCs. Oxygenated hemoglobin and deoxygenated hemoglobin have similar peak values, so we could judge the degree of hemolysis. When hemolysis occurred, the RBCs released hemoglobin, and the absorption spectra of hemoglobin was obtained at wavelength 420 nm. RESULTS AND DISCUSSION The results reveal that sufficient electric field intensity was generated, and the lysis rate of the planar electrode chip are shown in Table 1. Because of point discharge, the lysis rate of square and comb electrodes are more than that of saw-tooth electrodes. A maximum lysis efficiency of 66.7% was measured in square electrodes at 500 Hz and 40 V. Then, the parallel plate electrode chip was free from uneven distribution of the electric field and the height restrictions, and the cell lysis is presented in Figure 1, in which the cells maintained shape before lysis and broke down after lysis. Inputting 5 voltage to parallel plate electrode chip led to the lysis rate 95% in whole blood within 10 seconds. Thus, this chip has the advantages of less operating time, lower energy consumption, and smaller volumes of specimen (5 μl). The lysis rate is shown in Figure 2. After measuring the degree of hemolysis by UV-Vis, we observed that the absorbance in specimen after lysis was pretty close to complete hemolysis. The result reveals that this experiment can effectively release hemoglobin from the RBCs. Also, we verified the effect of surface modification on the microfluidic chip by contact angle detection. Compared with the unmodified chip, the contact angle of the modified chip reduced from 74° to 33°, and the effect of modification lasted for four weeks. With the rise of hydrophilicity, the microfluidic chips did not need external force because the specimen was carried to the detection region by surface modification and capillarity. CONCLUSION In this thesis, we proved that the simulation of electric field by ANSYS was feasible and reliable for chip design and fabricated miniaturization of lysis chip. By MEMS and microfluidic technology, the chip has the advantages of high lysis and hemolysis rate, small volume of specimen and short operating time. Therefore, the proposed system provides a new way for cell lysis and disease detection.