Dissertations / Theses on the topic 'Receptor assembly'
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Sagar, Rajeeve. "Self-assembly via hydrogen bonding." Thesis, University of Warwick, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.247352.
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Atlason, Palmi por. "The folding and assembly of NMDA receptor subunits." Thesis, University of Oxford, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.487137.
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The NMDA receptor is a member of the ionotropic glutamate receptor family, which includes the AMPA and kainate receptors. Functional NMDA receptors are heteromeric and made up from three receptor subunit families; NR1, NR2 and NR3. Currently, the receptor is thought to form in a dimer-of-dimer assembly with two NRI subunits and two NR2 subunits. The NR3 can associate with both NRI and NR2 to form a unique receptor or NRI alone to form an excitatory glycine receptor. The exact assembly pathway and the nature of assembly intermediates are currently unknown. The folding status of NR1, NR2A and NR3A was examined in heterologous systems, both individually expressed and co-expressed. It was found that while NRI appeared to fold well when expressed on its own and contain relatively few free cysteine residues, the NR3A subunit appeared to form aggregates when analysed under non-reducing conditions. BothNR2A and NR3A aggregated when treated with the sulfhydryl crosslinker BMH, indicating mUltiple free cysteine residues and a degree of misfolding. NRI migrated as a dimer when treated with BMH. A small pool of fast degrading NRI was detected but the majority of the protein was very stable in cells. NR2A and NR3A were turned over rapidly when expressed on their own with NR2A showing stabilisation in the presence of NRI. FRAP analysis indicated a degree of misfolding of NR2A and NR3A. NRI readily associated with both NR2A and NR3A but no association of NR2A and NR3A was detected in the absence ofNRl. The analysis of receptor assembly using BiFC confirmed the homodimerization of NRI but failed to give any evidence for homodimerization of either NR2A or NR3A. The BiFC analysis further indicates that the homodimer of NRI is readily disassociable. The robust complementation seen between NRI and NR2A, coupled with the absence of complementation ofNR2A and NR2A in the presence ofNRl suggest the preferential assembly of heterodimers. Possibly, steric constraints prevent complementation in the tetramer, suggesting a 1-2-1-2 symmetry around the pore. A similar constraint due to a coiled-coil domain in NR3A might explain the absence of complementation between NRI and NR3A. . Taken together, the results suggest the central role of NRI in the folding and assembly of the other subunit families. The probable assembly pathway suggests recruitment of NRI from an intracellular pool to associate with newly synthesised NR2 or NR3 to form heterodimers which then assemble to form the functional tetrameric receptor.
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Smith, Miriam Jane. "Studies of GABA_A receptor subunit assembly and processing." Thesis, University College London (University of London), 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.415891.
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Taylor, Pamela Mary. "Identification of assembly determinants in GABAâ†A receptor subunits." Thesis, University College London (University of London), 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.394507.
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Goebel, Erich J. "Insights into the Activin Class: Mechanisms of Receptor Assembly and Specificity." University of Cincinnati / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=ucin162316530833396.
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Nadler, Laurie Sue. "GABA(A) receptor subunit expression and assembly in rat cerebellar neurons." Case Western Reserve University School of Graduate Studies / OhioLINK, 1996. http://rave.ohiolink.edu/etdc/view?acc_num=case1057672368.
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Berglund, Jenny. "Structure-function studies of organelle assembly and receptor recognition in organelles assembled via the chaperone/usher pathway /." Uppsala : Dept. of Molecular Biology, Swedish Univ. of Agricultural Sciences, 2004. http://epsilon.slu.se/a441.pdf.
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Blümmel, Anne-Sophie [Verfasser], and Matthias [Akademischer Betreuer] Müller. "Initial assembly steps of the twin-arginine translocation signal peptide receptor complex." Freiburg : Universität, 2016. http://d-nb.info/1135118256/34.
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Legate, Kyle R. Andrews D. W. "Characterization of the beta-subunit of the mammalian SRP receptor and its role in assembly of the SRP receptor /." *McMaster only, 2003.
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Sukumaran, Madhav. "Biophysical investigations of AMPA receptor N-terminal domain structure and function reveal mechanisms underlying receptor assembly, dynamics, and allosteric potential." Thesis, University of Cambridge, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708278.
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Seidenkranz, Daniel. "Barbiturates and Modified Hamilton Receptors for Supramolecular Catalysis, Sensing, and Materials Applications." Thesis, University of Oregon, 2019. http://hdl.handle.net/1794/24194.
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Supramolecular chemistry (chemistry beyond the molecule) is the study and synthesis of complex molecular architectures from simple subunits using non-covalent interactions. The types of non-covalent interactions that are used for the self-assembly of these complex molecular architectures include electrostatic interactions (e.g. ionic, halogen, and hydrogen bonding), π-effects, van der Waals interactions, metal coordination, and hydrophobic effects. While these interactions are often used in concert, some of the most
successful and ubiquitous approaches for the design and construction of new host–guest architectures are the incorporation of hydrogen bonding motifs. A popular class of molecules capable of making strong, highly directional hydrogen bonds is barbiturates.
Barbiturates have a well-known reputation as potent hypnotics, anticonvulsants, and anxiolytics but recent years have seen a renewed interest in these molecules due to their unique, symmetric acceptor-donor-acceptor hydrogen bonding motif. In addition, receptors with complementary hydrogen bonding motifs capable of binding barbiturates have also been reported, namely those based on the work of Hamilton et al. Collectively, barbiturates and their receptors have seen widespread use in a variety of applications including sensing, optoelectronics, catalysis, and the design of soft materials.
The work presented in this dissertation describes the development of novel Hamilton receptors for supramolecular catalysis and barbiturate sensing, as well as the design of new synthetic barbiturates. Together this body of research aims to extend the utility of these types of host–guest systems as well as continue to develop and refine the
supramolecular design principles that govern the binding interactions between barbiturates and a variety of Hamilton-type receptors.
This dissertation includes both previously published/unpublished and co-authored material.
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Thevenin, Damien. "Roles of transmembrane domains in the folding and assembly of the adenosine A2A receptor." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 170 p, 2007. http://proquest.umi.com/pqdweb?did=1260822171&sid=2&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Cordier, Stefanie. "The role of the linear ubiquitin chain assembly complex (LUBAC) in death receptor signalling." Thesis, Imperial College London, 2012. http://hdl.handle.net/10044/1/14426.
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TNF is a cytokine with important functions in inflammation and immunity. Binding to its receptor TNF-Receptor-1 (TNFR1) induces the formation of a signalling platform which leads to TNF-target gene transcription and consequently the induction of cellular immune responses. To understand and possibly influence the effects observed upon TNF stimulation, it is important to define the molecular machinery responsible for signal transduction. In order to resolve the composition of the TNF-Receptor signalling complex (TNF-RSC) our group developed a highly sensitive modified tandem affinity purification method (moTAP). Using this technique, we recently reported on the recruitment of the two In-Between-RING (IBR) family members HOIL-1 (heme-oxidized IRP2 Ub ligase-1) and HOIP (HOIL-1 interacting protein) to the TNF-Receptor signalling complex (TNF-RSC) (reviewed in Haas et al, 2009). Together, HOIL-1 and HOIP form an E3 ligase complex that is capable of generating linear ubiquitin chains and therefore referred to as “linear ubiquitin chain assembly complex” (LUBAC) (Kirisako et al, 2006). In addition to HOIL-1 and HOIP, we also identified Sharpin (SHANK-associated RH domain-interacting protein) as a further component that is recruited to the TNF-RSC in a stimulation-dependent manner. In this study I show that Sharpin forms an endogenous, stimulation-independent complex with HOIL-1 and HOIP. Although the mRNA levels of HOIL-1 and HOIP are unchanged in the absence of Sharpin, their respective protein levels are strongly diminished. These data indicate that Sharpin, HOIL-1 and HOIP form a tripartite complex. As previously shown for HOIL-1 and HOIP, overexpression of Sharpin together with HOIP also stabilises the TNF-RSC and leads to activation of NF-kB. Therefore, LUBAC does not only consist of HOIL-1 and HOIP, but also includes Sharpin. A spontaneous point deletion in the Sharpin gene ablating its expression leads to the development of chronic proliferative dermatitis (cpdm) in mice (HogenEsch et al, 1993; HogenEsch et al, 1999; Seymour et al, 2007). Cpdm mice develop a multi-organ inflammatory disease with prominent skin lesions and display severe abnormalities in lymphoid architecture, including absence of Peyer’s patches, marginal zones, germinal centres, and follicular dendritic cells. Mouse embryonic fibroblasts (MEFs) and primary keratinocytes generated from these mice show impaired TNF-induced NF-kB and MAPK signalling. Although activation of these pathways is not completely dependent on LUBAC activity, its presence is required for full activation as demonstrated by proper induction of TNF-target genes. In line with these TNF-induced signalling defects, cpdm-derived cells are prone to TNF-mediated cell death, which is partially apoptotic and partially necroptotic. Thus, loss of Sharpin results in a cell death favouring dysregulation of TNF-induced signalling which is responsible for the inflammatory phenotype observed in cpdm mice. Following the identification of a role for LUBAC in TNF signalling I determined whether it also played a role in signalling by the TNF related ligands TRAIL and CD95 ligand (CD95L/FasL). As compared to TNF, absence of a LUBAC component also sensitised cells to TRAIL- and CD95L- induced cell death, indicating that LUBAC plays a crucial role in cell survival. Accordingly, non-apoptotic TRAIL- and CD95L-induced signalling was also affected in the absence of LUBAC as determined by altered NF-κB and MAPK responses, respectively. Taken together, the results obtained in this thesis determine LUBAC as a novel regulator of various death receptor-driven signalling pathways implicated in gene activation, cell death induction and, as a consequence, innate immunity and inflammation.
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Schmidt, Ralf [Verfasser], and Frank [Akademischer Betreuer] Würthner. "Hamilton-Receptor-Mediated Self-Assembly of Merocyanine Dyes into Supramolecular Polymers / Ralf Schmidt. Betreuer: Frank Würthner." Würzburg : Universitätsbibliothek der Universität Würzburg, 2012. http://d-nb.info/1021645737/34.
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Gerlach, Bjorn. "Identification and characterisation of the linear ubiquitin chain assembly complex (LUBAC) as a functionally important component of the CD40 receptor signalling complex." Thesis, Imperial College London, 2011. http://hdl.handle.net/10044/1/9117.
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CD40 is a member of the Tumour Necrosis Factor (TNF)-Receptor superfamily and plays an important role in maturation and differentiation of dendritic cells and B cells. In B cells, CD40 provides a costimulatory signal and facilitates differentiation, germinal centre formation and isotype switching. So far it has been shown that TNF-Receptor Associated Factors (TRAFs) and cellular Inhibitor of Apoptosis Proteins (cIAPs) are important mediators of CD40 signalling and needed for the activation of Nuclear Factor-κB (NF-κB) and Mitogen- Activated Protein Kinase (MAPK) signalling pathways. However, the exact function of these components and their biochemical interplay are still unknown. Hence, our understanding of the CD40-Receptor Signalling Complex (RSC) which initiates CD40 signal transduction is incomplete. In order to understand the biochemical processes that initiate CD40 signalling a new technique suitable to identify core components of the CD40-RSC was developed in this thesis. This technique is based on the employment of a tandem-tagged recombinant version of CD40 ligand to purify the CD40-RSC in two separate steps. This resulted in higher purity of the receptor complex and allowed for determining the composition of the CD40-RSC by mass spectrometry. This established protocol revealed the recruitment of three novel constituents to the CD40- RSC. HOIL-1, HOIP and SHARPIN are able to form the Linear Ubiquitin Chain Assembly Complex (LUBAC) which catalyses the formation of linear ubiquitin chains. This complex was only recruited to the CD40-RSC when highly ubiquitinated cIAP2 was also present. It was then shown that HOIL-1 and HOIP can bind to ubiquitin chains in vitro and that cIAPs are required for LUBAC recruitment to the CD40-RSC. Specific suppression of LUBAC components by RNA interference or by genetic ablation resulted in an inhibitory effect on CD40 signal transduction, gene induction and isotype switching caused by a defect in NF-κB and MAPK signalling.
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Emmerich, Christoph H. "Biochemical and functional characterisation of the Linear Ubiquitin Chain Assembly Complex (LUBAC) as a component of the TNF-Receptor 1 signalling complex." Thesis, Imperial College London, 2010. http://hdl.handle.net/10044/1/6186.
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Tumour necrosis factor (TNF) plays a critical role in inflammatory processes and is involved in the regulation of immune responses. Depending on the cellular context, TNF initiates a complex cascade of signalling events that can lead to induction of proinflammatory cytokines, cell proliferation, differentiation or cell death. Most of the pleiotropic effects of TNF are mediated by the death-domain (DD) containing TNF-R1. Ligand-induced trimerisation of TNF-R1 leads to the formation of an intracellular multiprotein complex, the TNF-R1 signalling complex (TNF-RSC). To be able to comprehend the complex network of signalling pathways emanating from TNF-R1, the TNF-RSC and its composition need to be understood at the molecular level. Using a modified tandem affinity purification approach, HOIL-1 and HOIP were identified as two novel, functional components of the native TNF-RSC. Together they were shown to form a linear ubiquitin chain assembly complex (LUBAC), catalysing the formation of linear head-to-tail ubiquitin chains. LUBAC mediates ubiquitination of NEMO with linear ubiquitin chains, required for efficient NF-kB activation following TNF stimulation. In this thesis, it could be demonstrated that the stimulation-dependent recruitment of LUBAC to the TNF-RSC is impaired in cIAP1/2-deficient mouse embryonic fibroblast (MEF) cell lines. Furthermore, it was shown that the E3 ligase activity of cIAPs, but not of TRAF2, is required for HOIL-1 recruitment to the TNF-RSC. This result, together with the ability of HOIL-1 and HOIP to bind polyubiquitin chains of various linkage types, suggests that LUBAC is recruited to the TNF-RSC via cIAP-generated ubiquitin chains. It was also found that LUBAC enhances NEMO interaction with the TNF-RSC, that it stabilises this protein complex and that LUBAC is required for efficient TNF-induced activation of NF-kB and JNK, resulting in apoptosis inhibition. Finally, it is shown in this thesis that the catalytic activity of LUBAC is required for stabilisation of the TNF-RSC, thereby adding a novel form of ubiquitin linkage to TNF signalling. The identification of HOIL-1 and HOIP as functional constituents of the TNF-RSC provides evidence that LUBAC is an important regulator at the apex of TNF-induced signalling cascades and increases the combinatorial complexity of ubiquitin modifications within this receptor complex.
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Nelson, Kjell Erik. "Investigating cell adhesion to controlled surface chemistry via self-assembly of binary composition alkylthiol monolayers, streptavidin immobilization, and cell receptor ligand attachment /." Thesis, Connect to this title online; UW restricted, 2003. http://hdl.handle.net/1773/8051.
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Lu, Thi Hong Thanh [Verfasser], Michael [Gutachter] Hollmann, and Stefan [Gutachter] Wiese. "Investigations on agonist specificity and heteromeric assembly of Arabidopsis thaliana glutamate-like receptor (AtGLR) subunits / Thi Hong Thanh Lu ; Gutachter: Michael Hollmann, Stefan Wiese." Bochum : Ruhr-Universität Bochum, 2017. http://d-nb.info/1123283524/34.
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Chen, Senbin. "Synthesis of original block copolymers by combination of RAFT polymerization and supramolecular self-assembly." Thesis, Lyon, INSA, 2012. http://www.theses.fr/2012ISAL0034.
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Ce travail a porté sur la préparation de copolymères à blocs et l’étude de leur assemblage supramoléculaire basé sur des liaisons hydrogènes entre les motifs homocomplémentaires ou hétérocomplémentaires. La stratégie de synthèse était basée sur la combinaison de la polymérisation radicalaire contrôlée de type RAFT et de la chimie supramoléculaire. Dans le chapitre 2, nous avons développé une stratégie s'appuyant sur la conception d'agents RAFT portant des groupements de type thymine / diaminopyridine (DAP) capables de générer des copolymères en étoile de type « miktoarm » bien définis. Pour élargir le champ d’application de ces agents RAFT capables d’établir des liaisons H, nous avons également étudié, dans le chapitre 3, la préparation d’agents RAFT fonctionnalisés par des motifs présentant de très hautes constantes de liaison. Le couple Hamilton / barbiturate (log (K) ≈ 4-5) a été sélectionné pour générer de plus stables copolymères à blocs supramoléculaires. Afin d’élaborer des macromolécules originales aux hautes propriétés d’association et de simplifier la stratégie de la synthèse, nous avons finalement exploré la préparation de copolymères tribloc ABC supramoléculaires à base de PA11 (oligomères OPA11) dans le chapitre 4. L’introduction d'un groupe dithiobenzoate pertinemment choisi sur les oligomères conduit à l’obtention de macroagents RAFT qui permettent la préparation de copolymères tribloc ABC supramoléculaires, où A est semi-cristallin, B à l'état caoutchouteux et C à l'état vitreux. Les études sur l'incorporation de tels copolymères dans les réseaux époxy sont en coursThis work dealt with the preparation and the study of supramolecular block copolymers based on hydrogen-bonding between homocomplementary or heterocomplementary stickers. The synthetic strategy was based on the combination of RAFT-mediated controlled radical polymerization and supramolecular chemistry. In the Chapter 2, we developed a strategy relying on the design of RAFT agents bearing thymine/diaminopyridine (DAP) recognition pairs and capable to grow well-defined miktoarm star supramolecular copolymers. To further extend the scope of H-bonding RAFT agents, in the Chapter 3, we also investigated the preparation of RAFT agents functionalized with motifs exhibiting very high binding constants. The Hamilton/barbiturate couple (log(K)≈4-5) was selected to generate more stable supramolecular block copolymers. Aiming at elaborating original associating macromolecules and at simplifying the strategy of synthesis, we finally explored the preparation ABC triblock supramolecular copolymers based on PA11 oligomers (OPA11) in Chapter 4. Ligation of a relevant dithiobenzoate group on the oligomers afforded oligomeric RAFT agents that allow for the preparation of ABC triblock supramolecular copolymers, where A is semi-crystalline, B in rubbery state and C in glassy state. Studies on the incorporation of such copolymers in epoxy networks are under progress
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Harish, S. "Transcriptional Regulation By Nuclear Receptor Homodimers Binding To The Direct Repeat Motif DR1 : Investigations In An in vitro Transcription System Derived From Rat Liver Nuclear Extracts." Thesis, Indian Institute of Science, 2000. http://hdl.handle.net/2005/164.
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Nuclear receptors (NRs) are important transcription factors involved in the regulation of a variety of physiological processes such as embryonic development, cell differentiation and homeostasis (for review, see Mangelsdorf et al., 1995 TenBaum and Baniahrned, 1997). In contrast to membrane bound receptors, they bind small lipophilic ligands and function in the nucleus as ligand-modulated transcription factors. The ligands for nuclear receptors include steroids (glucocorticoids, progestins, mineralocorticoids, androgens and estrogens), vitamin D3, retinoids, thyroid hormone, prostaglandins, farnesoids etc. Several other nuclear receptors are classified as orphan receptors for which no ligand has yet been identified.
More than 300 nuclear receptors have now been identified and together these proteins comprise the single largest family of metazoan transcription factors, the nuclear receptor superfamily. Recently, a unified nomenclature has been evolved (nuclear receptor nomenclature committee, 1999), a summary of which is presented in Table 1.
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Pennini, Meghan E. "Toll-like Receptor 2-dependent Inhibition of Interferon gamma Signaling by Mycobacterium tuberculosis." Connect to text online, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=case1152115234.
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Asencio, Hernandez Julia. "Novel approaches in NMR and biophysics for the study of complex systems : application to the N-terminal domain of the androgen receptor." Thesis, Strasbourg, 2015. http://www.theses.fr/2015STRAJ013/document.
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Cette thèse vise à réaliser une étude approfondie sur le développement de méthodologies pour l’analyse de systèmes complexes. Cela comprend l’étude des systèmes hors d’équilibre, des systèmes d’auto-assemblage, et les systèmes biologiques désordonnés. Les méthodes développées recouvrent principalement la RMN, tel que la mesure de diffusion (DOSY) mais également d’autres techniques telles que la spectrométrie de masse, le dichroïsme circulaire (CD), la microscopie électronique (EM) et diffusion des rayons X aux petits angles (SAXS). La partie N-terminale du récepteur des androgènes (AR) est utilisée comme un système complexe. D’après la littérature, il est connu que cette région joue un rôle important pour l’activité du récepteur, et elle est également décrite comme étant intrinsèquement désordonnée. Les résultats que j’ai acquis durant la thèse m’ont permis d’identifier une courte région de ce domaine, impliquée dans la formation réversible de fibres amyloïdes, par modulation des conditions d’oxydo-réduction du milieu. Les résultats révèlent un aspect inconnu du mécanisme de ARMy PhD project was focused on the development of methods for the analysis of complex systems and their biophysical characterization. This includes the study of large chemical libraries, self assembly systems, protein-ligand interaction studies and disordered biological systems. A wide range of biophysical methods were used for this purpose. Specially, Nuclear Magnetic Resonance(NMR) but also other techniques such as mass spectrometry, circular dichroism (CD), electron microscopy (EM) and small angle X-ray scattering (SAXS). The N-terminal Domain of the Androgen Receptor is studied as an example of a complex system. This region plays an important role in receptor activity, and is also described as being intrinsically disordered. The results obtained during my thesis shown a short conserved region involved in the amyloid fibers formation under oxidative conditions. These results open new possibilities to understand the mechanism of the AR activity
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Nagarajan, Naveen. "Molecular mechanisms of AMPA and kainate receptor gating and its implication in synaptic transmission." Doctoral thesis, [S.l.] : [s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=965898768.
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Kilb, Michael [Verfasser], Bodo [Akademischer Betreuer] Laube, and Ralf [Akademischer Betreuer] Galuske. "The role of the human glycine receptor transmembrane domains for the function, assembly and allosteric modulation by the general anesthetic propofol and closely related derivates / Michael Kilb ; Bodo Laube, Ralf Galuske." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2016. http://d-nb.info/1115856502/34.
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Guo, C. "Trafficking and assembly of P2X receptors." Thesis, University of Cambridge, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.599788.
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Within the P2X family, P2X7 is claimed to be unique in not forming heteromers; however, we have used different approaches to demonstrate that P2X4 and P2X7 interact both structurally and functionally. First, when heterologously co-expressed, P2X7 was co-localized with P2X4 at the plasma membrane and co-expression with P2X7 increased the proportion of P2X4 at the cell surface, as measured by surface biotinylation. Second, in co-expressed cells, P2X7 was co-immunoprecipitated with an anti-HA antibody that recognized an HA-tagged form of P2X4. Similarly P2X4 was co-immunoprecipitated with an antibody to P2X7. Third, co-expression with a dominant-negative mutant of P2X4 (P2X4 C353W) with either wild type P2X4 or P2X7 reduced the amplitudes of currents, whereas co-expression of a non-functional but non-dominant-negative mutant (P2X4 S341W) potentiated currents. Neither mutant exhibited an obvious trafficking defect, nor did they alter the surface expression of P2X7 as measured by biotinylation. Finally we identified novel pharmacological properties of the heteromeric receptors. Similar to P2X7 receptors, they are 1) preferentially activated by 2’,3’-O-(benzoyl-4-benzoyl)-ATP (BzATP) and ATP4- as compared to MgATP, 2) the currents desensitize slowly, 3) the currents are sensitive to extracellular Na+ and 4) currents are blocked by Brilliant Blue G (BBG). However, unlike P2X7, the heteromeric receptor currents were potentiated by ivermectin (IVM) and inhibited by 2’,3’-O-(2,4,6-trinitrophenyl) adenosine 5-triphosphate (TNP-ATP). In a separate study, molecular determinants of P2X2 receptor trafficking demonstrated that the last few amino acids within the C-terminus, which are conserved in different spliced forms of P2X2 receptors, appear to be involved in the stabilization of P2X2 receptors at the plasma membrane.
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Quintero-Martinez, Adrian. "Assembly and selectivity of asialoglycoprotein receptors." Thesis, Imperial College London, 2012. http://hdl.handle.net/10044/1/9232.
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Two galactose-binding receptors, the hepatic asialoglycoprotein receptor (ASGPR) and the macrophage galactose lectin (MGL) have been investigated. The ASGPR is believed to function in glycoprotein clearance from serum while MGL is involved in recognition of pathogens and tumours and in signalling and immunomodulation. This work describes the analysis of the specificity, structure and organisation of both receptors in humans and the two MGLs in mice. The ligand-binding properties of the two subunits of the ASGPR as well as MGL have been separately tested in glycan array analysis. The results show that primary binding to ligands in the human ASGPR occurs via the ASGPR-1 subunit. MGLs have different specificities even though they are highly similar in sequence and the two mouse MGLs differ markedly from the single MGL in humans and in rats. One of the mouse MGLs has a similar specificity to ASGPR-1 that evolved independently. Hydrodynamic studies of ASGPR-1 revealed that it can form homo-oligomers and circular dichroism analysis of the neck fragment showed that it has a coiled-coil structure. Hetero-oligomer formation was monitored using a mutant version of ASGPR1 that allows purification of the complex using double-affinity chromatography on galactose and mannose. Hetero-oligomers containing both types of subunits are more stable than homo-oligomers. The results suggest a model that can account for the variable subunit stoichiometries observed by various investigators. Hydrodynamic studies and circular dichroism of MGL suggest that the extracellular domain of the human protein is an oligomer not as stable as previously thought, and that its neck is a coiled-coil structure. For both receptors, transmembrane and cytoplasmic domains as well as glycosylation may have a role in their stability. The ability of MGL to recognise pathogen glycans was demonstrated using Trichinella spiralis secretions. It was found that similar glycoproteins are bound by the human and mouse receptors.
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Camiolo, Salvatore. "Anions in supramolecular chemistry : binding, sensing and assembly." Thesis, University of Southampton, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.252044.
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Bofinger, Robin. "Photocontrolled biomimetic communication between molecules and nanosystems in confined compartments." Thesis, Bordeaux 1, 2013. http://www.theses.fr/2013BOR14933/document.
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Cette thèse se focalise sur la synthèse et l'étude de nouvelles molécules photoactives et leurs applications en tant que marqueurs, senseurs moléculaires et récepteurs d’ions photomodulables en milieux aqueux et organisés. Les fluorophores développés sont principalement des dérivés du bore-dipyrométhene (BODIPY), comportant des groupements réactifs (azoture, perfluorophényle), des chaines hydrophobes, ou sont intégrés à un récepteur de calcium biocompatible. Le développement d'architectures auto-assemblées multicompartimentées de type vésicules dans des polymersomes géant y est décrit. Ces architectures ont été utilisées pour la génération de lumière blanche dans un micro-domaine, et constitue un modèle pour l'étude de transfert d'ions calcium entre vésicules localisées dans des polymersomes individuels. Ce transfert entre nano-objets confinés à l'intérieur d'un polymersome géant représente un système prototype de communication cellulaire artificiel rudimentaireThe thesis focuses on the study and design of novel photoactive molecules and their application as labeling agents, fluorescent molecular Ca2+-sensors and photolabile Ca2+-decaging agents in aqueous media and organized supramolecular assemblies. The designed fluorophores are based on boron-dipyrromethene (BODIPY) bearing hydrophobic chains or a reactive group like an azide or a perfluorophenyl moiety. Biocompatible calcium receptors have been prepared harnessing the fluorescence properties of BODIPY, naphthalimide and furan fluorophores. The development of self-assembled multicompartmentalized architectures, namely fluorocarbon vesicles in giant polymersomes is reported and the system has been used to create white light emission in confined microdomains. The Ca2+-based ion transfer ion the confined polymer compartments between individual fluorinated vesicles has been studied. The ion transfer in between vesicles in polymer microcompartments has been established as an artificial prototype system for cellular communication
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Doward, Anne Isabel. "Assembly and trafficking of nicotinic and 5HT₃ receptors." Thesis, University College London (University of London), 2005. http://discovery.ucl.ac.uk/1444630/.
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Nicotinic acetylcholine receptors (nAChRs) and 5-hydroxytryptamine type 3 receptors (5HT3R.S) are pentameric ligand-gated ion channels which form both heteromeric and homomeric complexes. Aspects of the assembly and pharmacological properties of the a 7 nAChR and 5HT3R were examined through three independent studies. The first study examined the mechanism by which the 5HT3B subunit, when expressed alone, is retained within the endoplasmic reticulum (ER). The 5HT3R forms both homomeric (composed of 5HT3A subunits) and heteromeric (composed of 5HT3A and 5HT3B subunits) complexes. In contrast to 5HT3A, the 5HT3B subunit cannot form a functional homomeric receptor. An ER retention motif (RAR) was identified in the 5HT3B subunit, which appears to be masked by the 5HT3A subunit. Evidence to support this conclusion was obtained from co-expression of the subunits, which resulted in the presence of 5HT3B on the cell surface. The a 7 nAChR and 5HT3R have similar N-terminal ligand binding domains and cross-reactivity of some ligands is observed. Both mouse 5HT3A and a 7 are potentiated by the aromatic moiety of 5-HT, 5-hydroxyindole (5-HI), whereas human 5HT3A is not. In an attempt to define the 5-HI binding site, human/mouse 5HT3A subunit chimeras were constructed. Studies using the chimeras suggest that the action of 5-HI may be mediated by both the N- and C-terminal domains of 5HT3A. In the final study, the effects of the putative chaperone protein, RIC3, on ct7 receptor expression were examined. The efficient functional expression of the cc7 nAChR has been shown to be critically dependent on host-cell type, unlike the 5HT3R. RIC3 was shown to facilitate the efficient cell-surface expression of al in a mammalian cell line, where functional expression was not previously observed. The RIC3 protein has been identified as an a7-interacting protein which promotes the efficient assembly and folding of the subunit. RIC3 was also shown to promote 5HT3aR assembly.
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Lansdell, Stuart John. "Folding and assembly of neuronal nicotinic acetylcholine receptors." Thesis, University College London (University of London), 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298829.
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Papadakis, Michalis. "Assembly and trafficking of NMDA receptors : a biochemical approach." Thesis, University College London (University of London), 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.415341.
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Berry, Neil. "Self-assembly of transition metal dithiocarbamate receptors for ionic guest species." Thesis, University of Oxford, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270002.
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Baragli, Alessandra. "Assembly and function of multimeric adenylyl cyclase signalling complexes." Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=111888.
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G protein coupled receptors, G proteins and their downstream effectors adenylyl cyclase (ACs) were thought to transiently interact at the plasma membrane by random collisions following agonist stimulation. However a growing number of studies have suggested that a major revision of this paradigm was necessary to account for signal transduction specificity and efficiency. The revised model suggests that signalling proteins are pre-assembled as stable macromolecular complexes together with modulators of their activity prior to receptor activation. How and where these signalling complexes form and the mechanisms governing their assembly and maintenance are not completely understood yet. Initially, we addressed this question by exploring AC2 interaction with beta2-adrenergic receptors (beta2ARs) and heterotrimeric G proteins as parts of a pre-assembled signalling complex. Using a combination of biophysical and biochemical techniques, we showed that AC2 interacts with them before it is trafficked to the cell surface in transfected HEK-293 cells. These interactions are constitutive and do not require stimulation by receptor agonists. Furthermore, the use of dominant-negative Rab/Sar monomeric GTPases and dominant-negative heterotrimeric G protein subunits proved that AC2/beta2AR and AC2/Gbetagamma interactions occurred in the ER as measured using both BRET and co-immunoprecipitation experiments, while interaction of the Galpha subunits with the above complexes occurred at a slightly later stage. Both Galpha and Gbetagamma played a role in stabilizing these complexes. Our data also demonstrated that stimulation of AC was still possible when the complex remained on the inside of the cell but was reduced when the GalphaS/AC2 interaction was blocked, suggesting that the addition of the GalphaS subunit was required to render the nascent complexes functional prior to trafficking to proper sites of action. Next, we tackled the issue of higher order assembly of effectors and G proteins, using two different AC isoforms and GalphaS as a model. We demonstrated that AC2 can form heterodimers with AC5 through direct molecular interaction in unstimulated HEK-293 cells. AC2/5 heterodimerization resulted in a reduced total level of AC2 expression, which affected cellular accumulation of cAMP upon forskolin stimulation. The AC2/5 complex was stable in presence of receptor or forskolin stimulation. We provided evidence that co-expression with GalphaS increased the affinity of AC2 for AC5 as monitored by BRET. In particular, the complex formed by AC2/5 lead to synergistic accumulation of cAMP in presence of GalphaS and forskolin, with respect to either of the parent AC isoforms themselves. Finally, we also showed that this complex can be detected in native tissues, as AC2 and AC5 could be co-immunoprecipiated from lysates of mouse heart. Taken together, we provided evidence for stable formation of signalling complexes involving receptor/G proteins/adenylyl cyclase or G proteins/heterodimeric adenylyl cyclases and that G proteins play a crucial role for their assembly and function.
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Liu, Yuan. "Acyclic and Macrocyclic Transition Metal Receptors for Anion : Recognition and Pseudorotaxane Assembly." Thesis, University of Oxford, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.504425.
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Pratt, Michelle. "Metal-directed self-assembly and anion recognition properties of transition metal-based receptors." Thesis, University of Oxford, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.269331.
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McConnell, Anna J. "Heteroditopic calix[4] arene based receptors for ion-pair recognition and mechanical bond assembly." Thesis, University of Oxford, 2010. https://ora.ox.ac.uk/objects/uuid:92d46010-5708-4f52-8075-0bded70a2203.
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This thesis investigates the design, synthesis and binding properties of novel calix[4]arene based heteroditopic receptors and interlocked structures. Chapter 1 introduces the field of supramolecular chemistry. The areas of host-guest chemistry and self-assembly are introduced, with a particular emphasis on strategies for designing receptors for ions and synthesising interlocked structures. Chapter 2 details the synthesis and binding properties of calix[4]arene based ion-pair receptors. These receptors show cooperative AND ion-pair recognition, where the receptors show little affinity for the 'free' ions but enhanced binding of the ion-pair. The extension of this work to the synthesis of their cryptand analogues is also explored. Finally, efforts towards preparing calix[4]arene based zinc Schiff base anion receptors is reported. Chapter 3 describes the synthesis of the first calix[4]arene based rotaxane host systems for anions using a new ion-pair templation strategy. NMR spectroscopy and X-ray crystallography demonstrate the successful interlocking of the macrocycle and axle components in the rotaxane structures. Anion binding studies reveal the importance of preorganisation of the host binding cavity on anion binding. The synthesis of rotaxanes using a stoppering approach and catenanes using a ring closing metathesis clipping strategy is also investigated. Chapter 4 investigates the use of copper catalysed coupling reactions, such as Eglinton coupling and click chemistry, in the preparation of interlocked structures. The synthesis and anion binding properties of a novel catenane are described. Efforts towards the first anion templated synthesis of rotaxanes by slippage and kinetic slippage studies are also reported. Chapter 5 reports the experimental procedures and characterisation details of the compounds synthesised in this thesis. Chapter 6 gives supplementary information about titration protocols, kinetic experiments and X-ray crystal structures.
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SMUKSTE, INESE. "ARTIFICIAL RECEPTORS FOR MOLECULAR RECOGNITION OF AMINO ACIDS, PEPTIDES AND CARBOHYDRATES." University of Cincinnati / OhioLINK, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1029757614.
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Pettersen, Jade Kristin. "Preparation and properties of self-assembled resorcinarene monolayers." Thesis, Curtin University, 2010. http://hdl.handle.net/20.500.11937/933.
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Several resorcinarene and calixarene based receptors were synthesised with the overarching aim of developing selective hydrocarbon sensors for application in the petroleum exploration industry.Thioacetyl resorcinarenes functionalised at the upper rim with methoxy, propoxy and benzyloxy groups were synthesised, along with a methylene bridged cavitand. Similar hydroxy and methoxy resorcinarenes functionalised at the lower rim with decylsulfide groups were prepared, along with a p-tert-butylcalix[4]arene thiol derivative.The receptors were allowed to self-assemble on gold substrates, and the resulting surfaces were characterised by contact angle, polarised modulation infrared reflection absorption spectroscopy (PMIRRAS), and atomic force microscopy (AFM). The results indicated that all but one of the receptors form monolayers. The exception, a resorcinarene decyl sulfide, appears to form a bilayer or multilayers.AFM force spectroscopy was used to investigate the receptor properties of the monolayers by using tips functionalised with adamantyl, cyclohexyl and benzyl molecular probes. A quantity of a deep cavitand was obtained to use as a comparison to the shallower receptors synthesised.Specific interactions were observed between the benzyloxy and methylene cavitand monolayers and the adamantyl probes. These monolayers along with the methoxy resorcinarene monolayer also showed significant interactions with the cyclohexyl probes. These receptors present promising targets for further studies of the complexation behaviour of resorcinarene based receptors and cyclic aliphatic hydrocarbons.All surfaces exhibited interactions with the benzyl probes. The propoxy resorcinarene and deep cavitand monolayers appear to show selectivity towards the benzyl probes with no interactions observed for the adamantyl or cyclohexyl probes.The binding of the monolayer was found to be influenced by not only the macrocylic receptor site, but also the monolayer structure. Evidence for this was provided by the difference in binding exhibited by the methoxy resorcinarene thiol monolayer and the methoxy resorcinarene decylsulfide monolayer.
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Nandadasa, Sumeda A. "Cadherin mediated F-actin assembly and the regulation of morphogenetic movements during Xenopus laevis development." University of Cincinnati / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1276953030.
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Meddows, Elisabeth. "Identification of the molecular determinants important in the assembly of N-methyl-D-aspartate (NMDA) receptors." Thesis, University of Oxford, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.365682.
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Dry, Emily Fiona Valentine. "Exploration of the dynamic chemistry of a subcomponent self-assembled dicopper(I) anion receptor." Thesis, University of Cambridge, 2014. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708170.
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Charlesworth, Scott. "Design of photo-switchable self-assembled monolayers for the study of protein-receptor interactions." Thesis, University of Birmingham, 2012. http://etheses.bham.ac.uk//id/eprint/3847/.
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Nano-biotechnology combines recent advances in nanotechnology with biology. It is a relatively new discipline and full of promise. One such promise is the elucidation of complex bio-molecular reactions and interactions, the elucidation of which requires the development of reliable in-vitro models. Such models could be developed through the use of self-assembled monolayer’s (SAMs). Research into this competitive field has already started and there is currently a call to develop SAMs which present specific bio-molecules in a switchable fashion; switchable SAMs can have their surface properties switched between two states, i.e. they can be switched ‘on’ or ‘off’. Such switch-ability would help such models mimic the real time changes of the bodies’ bio-chemistry and is a vital development. This thesis addresses this current research need, through the employment of azobenzene based SAMs. Currently the switch-ability (isomerisation) of numerous azobenzene SAMs has been shown to be hindered by a lack of inter-surfactant space. This hindrance to isomerisation is addressed in Chapter 4. While Chapter 5 explores the design of an azobenzene based photo-switchable SAM, for use as in-vitro model for the study of bio-molecular interactions. The two chapters are not directly related and future work would aim to bring the findings together.
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Oshovsky, Gennady Veniaminovich. "Cavitand-based anion receptors and self-assembled (hemi)capsules in polar competitive media." Enschede : University of Twente [Host], 2006. http://doc.utwente.nl/55450.
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Liang, Chih-Kai. "Photocontrôle d'événements de reconnaissance moléculaire au sein de récepteurs greffés sur des surfaces : vers des ardoises supramoléculaires." Thesis, Bordeaux 1, 2012. http://www.theses.fr/2012BOR14645/document.
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Des récepteurs de barbiturates greffés avec des groupements anthracène photoactifs possédant différentes fonctions d’ancrage ont été synthétisés et caractérisés, en vue de transférer leurs propriétés de reconnaissance photocontrôlable à des substrats par diverses techniques de modification, comme la formation de liaisons amide, de liaisons thioacétate, ou par réaction click. Les propriétés photophysiques et photochimiques de ces récepteurs ont été étudiées en solution, et la fluorescence, la durée de vie et le rendement quantique ont été mesurés à différentes températures. Des surfaces d’or modifiées ont été fabriquées et caractérisées par ellipsométrie, mesure d’angle de contact, AFM et PM-IRRAS. Les résultats montrent qu’il est possible de moduler les propriétés de reconnaissance moléculaire des récepteurs de manière réversible via une combinaison d’irradiation lumineuse (365 nm) et de chaleur (80 °C)Anthracene-appended photoactive barbiturate receptors possessing various anchoring groups are synthesized and characterized in view of transferring their photocontrolled binding properties onto substrates through various surface grafting techniques, such as amide bond formation, direct thioacetate linkage, or post click reaction modification. The photophysical and photochemical properties of the synthesized receptors were investigated in solution using variable temperature fluorescence, lifetime measurement and reaction quantum yield measurements. Receptor-modified gold substrates were characterized using ellipsometry, contact angle, AFM and PM-IRRAS experiments. The results showed that it is possible to reversibly modulate the binding properties of the anthracene-appended receptors through a combination of the irradiation with light (365nm) and heat (80℃)
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Skehan, Brian M. "Functional Elements of EspFu, an Enterohemorrhagic E. coli Effector that Stimulates Actin Assembly: A Dissertation." eScholarship@UMMS, 2009. https://escholarship.umassmed.edu/gsbs_diss/443.
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Enterohemorrhagic Escherichia coli O157:H7 (EHEC) is an attaching and effacing pathogen that upon attachment to host cells, induce characteristic attaching and effacing lesions and formation of F-actin rich pedestals beneath sites of bacterial attachment. EHEC harbors a Type III secretion system through which it delivers dozens of effectors into the host cell. The two secreted effectors critical for EHEC-mediated actin pedestal formation are the translocated intimin receptor (Tir) and EspFU. EspFU consists of an N-terminal secretion signal and a C-terminus containing six tandem 47-residue proline-rich repeats, each of which can bind and activate the actin nucleation promoting factor N-WASP. Structural and functional analyses described here have identified the mechanism of N-WASP activation by EspFU and the minimal domains and specific residues required for this activity. While EspFU and Tir are the only bacterial effectors required for F-actin pedestal formation, recruitment of EspFU to Tir is mediated by an unidentified putative host factor. To identify the host factor responsible for linking these two effectors, a combination of in vitro and functional assays were used to identify the host factor, IRTKS and the residues required for these interactions were defined. Further, the presence of at least two 47-residue repeats in all characterized clinical isolates of canonical EHEC strains led us to address the minimal requirements for EspFU functional domains to promote recruitment to Tir and N-WASP activation. Here we show that two proline-rich elements of EspFU are required for recruitment of EspFU by IRTKS to sites of bacterial attachment. Furthermore, once artificially clustered at the membrane, a single N-WASP binding element of EspFU can induce actin pedestal formation.
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Jeamet, Emeric. "Études structurales et propriétés de reconnaissance d'objets auto-assemblés." Thesis, Lyon, 2018. http://www.theses.fr/2018LYSE1024/document.
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Depuis les années 1990, la chimie combinatoire dynamique permet la découverte et la préparation de nouveaux récepteurs synthétiques à partir de briques moléculaires simples sous contrôle thermodynamique. Dans ce contexte, nous avons récemment décrit une nouvelle famille de para-cyclophanes dynamiques: les dyn[n]arènes. Ces macrocycles, composés de briques moléculaires 1,4-bisthiophénoliques fonctionnalisées, ont pu être obtenus à l'échelle du gramme à partir d'une procédure simple ne mettant pas en jeu de purification par chromatographie. Cette accessibilité synthétique a rendu possible une étude structurale permettant la rationalisation des forces motrices mises en jeu lors des processus d'auto-assemblage, mais aussi de leurs propriétés de reconnaissance moléculaire vis-à-vis de molécules ioniques. A partir de données expérimentales et de calculs réalisés en chimie théorique, les phénomènes physiques responsables de la sélectivité et de l'affinité remarquables observées entre l'un des membres de cette famille, un dyn[4]arène poly anionique, et une série d'a,?-alkyle-diamines ont été étudiés. Finalement, au cours de cette étude, nous avons redécouvert une voie de synthèse simple menant à une famille de molécules encore peu étudiée : les dithiocines. La fonctionnalisation de ces objets a été explorée dans le but d'obtenir une plateforme multifonctionnelle pour des applications biologiquesSince the 1990s, dynamic combinatorial chemistry has allowed the discovery and preparation of new synthetic receptors from simple building blocks under thermodynamic control. In this context, we have recently described a new family of dynamic para cyclophanes, the so-called dyn[n]arenes. These macrocycles, made from functionalized 1,4-bisthiophenolic building blocks, could be obtained on a gram scale from a simple purification procedure, and without any chromatography. Their synthetic accessibility allows us to study the driving forces behind their self-assembly, as well as their molecular recognition properties towards ionic guest molecules. Experimental and computational experiments were also conducted to reveal the subtle physical phenomena that are responsible for the remarkable selectivity and affinity observed between a poly-anionic dyn[4]arene and a series of a,?-alkyl-diamines. During these previous studies, we rediscovered a simple synthetic route towards a family of molecules that is unexploited so far: the dithiocins. The functionalization of these molecular objects has been explored in order to generate versatile platforms for biological applications
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Marshall, Tracey. "Dynamic chemistry : nucleobase recognition by synthetic receptors and cis-trans acylhydrazone isomerism." Thesis, Bordeaux 1, 2012. http://www.theses.fr/2012BOR14477/document.
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Chimie dynamique: reconnaissance de nucléobases par des récepteurs synthétiques et isomérie cis-trans d'hydrazones acylées.Ce travail traite du développement des systèmes moléculaires qui peuvent s'adapter à l'addition de substances qui agissent comme un gabarit. Cette approche permet d'isoler une espèce majeure à partir d'un mélange de composés par le biais de la chimie combinatoire dynamique (CCD). La première partie de ma thèse de doctorat inclus l'utilisation d'un ADN simple brin (ADNsb) comme un gabarit pour le transfert d'information par auto-assemblage de récepteurs sans avoir besoin d'enzyme. De nouveaux récepteurs de l'adénine et de la guanine (pinces A et G) solubles dans l'eau ont été conçues dans ce but. Une approche utilisant la résonance magnétique nucléaire (RMN) a été utilisée pour déterminer l'affinité de liaison comme preuve d'une reconnaissance spécifique et efficace. Une évaluation dans l'eau par dichroïsme circulaire (CD) et mesure de la température de fusion par UV (Tm) a été réalisée. Cela a permis de tester respectivement la capacité d'auto-assemblage entre les pinces et un modèle ADNsb, et la force du processus de coopérativité. La deuxième partie de ce travail est axée sur le tri spontanné de motifs pyridine acylhydrazone et sur les configurations intéressantes qu'ils adoptent. Nous avons étudié la synthèse d'une série de motifs pyridine acylhydrazone: dimère, trimères et pentamères. Des études RMN ont permis d'évaluer les changements dans l'équilibre configurationnel cis / trans de ces systèmes dynamiques. Les études ont montré que l'équilibre attendu est biaise la cis acylhydrazone pyridine isomère a été observée par diffraction des rayons XDynamic chemistry: nucleobase recognition by synthetic receptors and cis-trans acylhydrazone isomerism. This work deals with the development of molecular systems which can adapt upon the addition of substances that act as templates. This approach enables one major species to be identified from a mixture of compounds through the use of dynamic combinatorial chemistry (DCC). The first part of my PhD included the use of a single stranded DNA (ssDNA) as a template for information transfer via the self-assembly of receptors without the need for enzymes. New water soluble adenine and guanine receptors (A and G clamps) were designed and synthesised for this purpose. Nuclear magnetic resonance (NMR) titration studies were carried out to calculate the binding affinity and as a proof of specific and efficient recognition. An assessment in water via circular dichroism (CD) and UV temperature melting (Tm) studies was carried out. This tested the ability for self-assembly between the clamps and a ssDNA template and the strength of the cooperative process respectively. The second part of my PhD focused on the self-sorting of acylhydrazone pyridine motifs and the interesting configurations they adopt. The feasibility to synthesise these acylhydrazone pyridine motifs (dimer, trimers and pentamers) was investigated. X-ray and NMR studies showed that the equilibrium was found to be biased in an unusual way, and the cis acylhydrazone pyridine isomer was observed
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Giraudat, Jérôme. "Etude de l'organisation fonctionnelle des chaines polypeptidiques du récepteur nicotinique de l'acétylcholine." Paris 6, 1986. http://www.theses.fr/1986PA066403.
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Chen, Pengkun. "Titania and silica based hybrid porous nanomaterials : from synthesis to applications." Thesis, Strasbourg, 2017. http://www.theses.fr/2017STRAF010/document.
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Mon doctorat se focalise sur la synthèse, la caractérisation et les applications de matériaux poreux à base de silice, dioxyde de titane et zéolite. La silice poreuse, le dioxyde de titane et les zéolites ont été synthétisés en utilisant des méthodologies différentes. Des matériaux de silice fonctionnalisés ont été utilisés pour des applications en adsorption de colorant, ce qui est utile pour le traitement de l'eau. Un nouveau système réticulé et un nouveau dispositif ont été créés pour améliorer la capacité d'adsorption et pour le traitement d’une grande quantité d'eau. En tirant parti des pores, une nouvelle méthode de formation de clusters de Cu (0) a été établie. Les propriétés photophysiques ont été étudiées, en utilisant plusieurs sources de cuivre et différents matériaux poreux. L'utilisation du confinement pour la détection de petites molécules biologiques tels que les neurotransmetteurs a été démontrée. Plusieurs applications ont été développées sur la base de ces récepteurs de neurotransmetteurs artificiels. Un matériau de titane mésoporeux multifonctionnalisé a été utilisé pour les applications en biologie. En comparaison avec la silice, plus couramment utilisée, sa photoactivité pourrait apporter des avantages supplémentaires. Finalement, de nouveaux types de matériaux de type organotitanes hybrides ont été développés, et leurs propriétés photo-catalytiques ont été démontréesMy PhD research focus on the synthesis, characterization and applications of silica, titania and zeolite based porous materials. Porous silica, titania and zeolite have been synthesized using different methodologies. Functionalized silica materials have been used for dye adsorption application which is useful for water treatment. A new cross-linked system and device have been created to enhance the adsorption ability and for large quantity of water treatment. By taking advantage of the pores, new method for Cu(0) cluster formation have been established. The photophysics of the Cu(0) clusters reduced from different copper source in different porous materials has been investigated. The use of the confinement for sensing has been demonstrated for small bio molecules, such as neurotransmitters. Several applications have been developed based on this artificial neurotransmitter receptors. Multi-functionalized mesoporous titania material has been used for bio-applications. Compare to the widely used silica material, its photoactivity could bring extra advantages. Finally, new types of hybrid organotitanium materials have been developed and their photocatalytic properties have been investigated
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McClure, Barbara Jean. "Molecular Assembly of the Activated Granulocyte-Macrophage Colony-Stimulating Factor Receptor." Thesis, 2017. http://hdl.handle.net/2440/119329.
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