Thèses : « Biochemical Study »

1

Paton, F. M. "Biochemical studies of marine fungi." Thesis, University of Liverpool, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382060.

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2

Nabi, A. "Immobilized bioluminescent reagents in flow injection analysis." Thesis, University of Hull, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381888.

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3

Khan, M. R. "Phytochemical study of some Costa Rican plants." Thesis, University of Strathclyde, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381696.

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4

Yi, X. "Immunological and biochemical studies on Schistosoma mansoni surface antigens." Thesis, University College London (University of London), 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.378926.

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5

Freije, Afnan Mahmood. "A biochemical study of thyroid hormone antibodies." Thesis, University of Surrey, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.277595.

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6

Osborne, Leisa Jane. "Characterisation of Thioredoxin Dimers: A Biochemical Study." Thesis, Griffith University, 2011. http://hdl.handle.net/10072/365531.

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In addition to the conserved active site cysteines that are responsible for the classical redox activity of thioredoxins (Trx’s), vertebrate Trx’s contain an additional three conserved cysteines at position 62, 69 and 73. These structural cysteines are known to be subjected to a variety of post translational modifications including dimerisation that are believed to contribute to the regulation and diversity of function of vertebrate Trx’s. Reports of the formation of “disulphide linked dimers” have been a long standing observation since the earliest studies on vertebrate Trx’s, however detailed studies on dimerisation have been limited in number and the extent of characterisation achieved. Despite the potential for a diversity of dimeric forms with different structural and functional properties there has been a common assumption arising from the literature (despite some evidence to the contrary) that all dimers so far described are much the same and all are redox inactive. Thesis (PhD Doctorate) Doctor of Philosophy (PhD) School of Biomolecular and Physical Science Science, Environment, Engineering and Technology Full Text

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7

Guise, Andrew David. "A biochemical engineering study of lysozyme refolding." Thesis, University of Bath, 1996. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337816.

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8

Mojumdar, Aditya. "Structural and Biochemical study of human RECQ4." Doctoral thesis, Università degli studi di Trieste, 2015. http://hdl.handle.net/10077/11141.

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2013/2014 RecQ helicases belong to a ubiquitous family of DNA unwinding enzymes that are essential to maintain genome stability by acting at the interface between DNA replication, recombination and repair. Humans have five different paralogues of RecQ helicases namely RecQ1, BLM, WRN, RecQ4 and RecQ5. This work focuses on the structural and biochemical study of human RecQ4. Germ-line mutations in the RECQ4 gene give rise to three distinct human genetic disorders (Rothmund-Thomson, RAPADILINO and Baller-Gerold syndromes). Despite the important roles of RecQ4 in various cellular processes, RecQ4 have never been fully characterized. In addition to the helicase domain, RecQ4 has a unique N-terminal part that is essential for viability and is constituted by a region homologous to the yeast Sld2 replication initiation factor, followed by a cysteine-rich region, predicted to fold as a Zn knuckle. A part of this work focuses on the structural and biochemical analysis of both the human and Xenopus RecQ4 cysteine-rich regions, and shows by NMR spectroscopy that the Xenopus fragment does indeed assumes the canonical Zn knuckle fold, whereas the human sequence remains unstructured, consistent with the mutation of one of the Zn ligands. Both the human and Xenopus Zn knuckles bind to a variety of nucleic acid substrates, with a preference for RNA. We also investigated the effect of an additional Sld2 homologous region upstream the Zn knuckle. In both the human and Xenopus system, the presence of this region strongly enhances binding to nucleic acids. These results reveal novel possible roles of RecQ4 in DNA replication and genome stability. Recently the catalytic core of RecQ4 has been predicted to include RecQ-like-C-terminal (RQC) domain at the C-terminus of the helicase domain, similar to other RecQ helicases. This domain is composed of a Zn-binding region and a winged helix (WH) domain. Another part of this thesis centers on the structural and biochemical characterization of the catalytic core of RecQ4 including the helicase and RQC domain. The results provide an insight in the Zn binding ligands present in the RQC domain that plays a role in DNA binding and unwinding activity of the protein. Also the presence of the characteristic aromatic residue at the tip of the WH β hairpin and its role in DNA binding and unwinding has been established. Finally, it provides a low resolution SAXS model of the catalytic core of RecQ4. Elicasi RecQ appartengono a una famiglia ubiquitaria di DNA svolgimento enzimi che sono essenziali per mantenere la stabilità del genoma agendo all'interfaccia tra replicazione del DNA, ricombinazione e riparazione. Gli esseri umani hanno cinque diversi paralogues di RecQ elicasi cioè RecQ1, BLM, WRN, RecQ4 e RecQ5. Questo lavoro si concentra sullo studio strutturale e biochimica di RecQ4 umana. Mutazioni germinali nel gene RECQ4 danno luogo a tre malattie genetiche umane distinte (Rothmund-Thomson, RAPADILINO e sindromi Baller-Gerold). Nonostante i ruoli importanti di RecQ4 in diversi processi cellulari, RecQ4 non sono mai stati pienamente caratterizzato. In aggiunta al dominio elicasi, RecQ4 ha una parte unica N-terminale che è essenziale per la vitalità ed è costituito da una regione omologa al lievito Sld2 fattore di iniziazione replica, seguita da una regione ricca di cisteina, previsto per piegare come stinco Zn . Una parte di questo lavoro si concentra sull'analisi strutturale e biochimica sia della regioni ricche di cisteina Xenopus RecQ4 umana e, e spettacoli di spettroscopia NMR che il frammento Xenopus effettivamente assume la canonica Zn nocca volte, mentre la sequenza di resti umani non strutturato, coerente con la mutazione di uno dei ligandi Zn. Sia il nocche Xenopus Zn umana e si legano ad una varietà di substrati di acido nucleico, con una preferenza per l'RNA. Abbiamo anche studiato l'effetto di un ulteriore regione omologa Sld2 monte la nocca Zn. Sia il sistema Xenopus umano e, la presenza di questa regione migliora fortemente legame ad acidi nucleici. Questi risultati rivelano possibili ruoli nuovi di RecQ4 nella replicazione del DNA e la stabilità del genoma. Recentemente il nucleo catalitico di RecQ4 stato previsto per includere RecQ-like-C-terminale (RQC) dominio al C-terminale del dominio elicasi, simile ad altri elicasi RecQ. Questo dominio è costituito da una regione-Zn vincolanti e un'elica alato (WH) dominio. Un'altra parte di questa tesi incentrata sulla caratterizzazione strutturale e biochimica del nucleo catalitico della RecQ4 compreso il elicasi e il dominio RQC. I risultati forniscono una descrizione nel Zn ligandi presenti nel dominio RQC che svolge un ruolo nel legame al DNA e l'attività svolgimento della proteina legante. Inoltre è stata stabilita la presenza della caratteristica residuo aromatico sulla punta della forcella WH β e il suo ruolo nel legame al DNA e di svolgimento. Infine, esso fornisce una bassa risoluzione SAXS modello del nucleo catalitico di RecQ4. XXVII Ciclo 1985

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9

Asante, Emmanuel A. "Biochemical genetics of lipid metabolism in chickens and mice." Thesis, University of Edinburgh, 1988. http://hdl.handle.net/1842/11520.

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10

Zhang, Jing. "Biochemical Study and Technical Applications of Fungal Pectinase." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Universitetsbiblioteket [distributör], 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6295.

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11

林德深 and Tak-sum Lam. "A biochemical study of mammalian x chromosome inactivation." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1987. http://hub.hku.hk/bib/B31981306.

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12

Lawson, Graham J. "A biochemical study of methylpredinsolone-hemisuccinate in man." Thesis, University of Surrey, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.308714.

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13

Odendaal, Ruenda. "A biochemical and immunological study of horseradish peroxidase." Thesis, Stellenbosch : University of Stellenbosch, 2009. http://hdl.handle.net/10019.1/1587.

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Thesis (MSc (Biochemistry))--University of Stellenbosch, 2009. ENGLISH ABSTRACT: This study describes: a) the isolation and purification of horseradish peroxidase isoenzymes from horseradish roots, b) the characterization of various forms and components of the enzyme by cation-exchange and reversed-phase high performance liquid chromatography, c) the preparation of antibodies against horseradish peroxidase isoenzymes, d) immunological studies for the development of an isoenzyme quantification method and e) the formation of an enzyme-melamine conjugate for use in a melamine quantification immunoassay. AFRIKAANSE OPSOMMING: Hierdie studie beskryf: a) die isolering en suiwering van peperwortel-peroksidase-isoënsieme vanuit die peperwortel, b) die karakterisering van verskillende vorme en komponente van dié ensiem deur katioonuitruilings en omgekeerde-fase HPLC c) die voorbereiding van teenliggaampies vir peperwortel-peroksidase-isoënsieme, d) immunologiese studies vir die ontwikkeling van 'n isoënsiem-kwantifiseringsmetode; en e) die vorming van 'n ensiem-melamien-konjugaat vir gebruik in 'n melamienkwantifiseringsmetode.

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14

Willemsen, Robert. "Gaucher disease an immunoelectron microscopic and biochemical study /." [S.l.] : Rotterdam : [The Author] ; Erasmus University [Host], 1995. http://hdl.handle.net/1765/13738.

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15

Lam, Tak-sum. "A biochemical study of mammalian x chromosome inactivation." [Hong Kong : University of Hong Kong], 1987. http://sunzi.lib.hku.hk/hkuto/record.jsp?B12827186.

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16

Marco-Casanova, Paola. "Chemical genetics to study how cells enter mitosis." Thesis, University of Cambridge, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609995.

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17

Liu, Yandi. "A study of the biochemical development and toxicology of the seed of Santalum spicatum." Thesis, Curtin University, 1997. http://hdl.handle.net/20.500.11937/2454.

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The seed of Santalum spicatum is rich in a fixed oil (59% by weight), which is characterised by a high percentage of acetylenic, ethylenic ximenynic acid (35% of total fatty acids). A number of important aspects of the seed fixed oil, its composition in developing seeds, its triacylglycerols molecular species in the oil, the nutrition and toxicity of the oil feeding, and the possible bioactivity of ximenynic acid in mice were investigated.The identification of cis and trans isomers of ximenynic acid in the seed oil, and the metabolite of ximenynic acid in mouse liver lipid fractions were achieved using 2-amino-2-methyl-1-propanol to form 2-substituted 4,4-dimethyloxazoline derivatives, which were analysed by gas chromatography with mass spectrometric detection.Changes in proximate and fatty acid composition were investigated in developing seed collected weekly from about seven days after flowering to maturity. It was determined that moisture and carbohydrate contents decreased significantly during the development sequence, while fixed oil content increased from 0.3% to 50% (by weight) with seed development. A corresponding increase in the proportions of both oleic and ximenynic acids occurred suggesting a precursor/product relationship. Mature seed collected from different locations in Western Australia showed minor differences in characteristics and lipid composition, which may have been influenced by geographical origin and harvesting year of samples.The lipid components from the seed oil were separated using thin-layer chromatography and the individual triglyceride bands were characterised by high performance liquid chromatography and gas chromatography using flame ionisation and mass spectrometric detection after removal from the plate. The triximenynin (trisantalbin) band showed no other contaminating fatty acids and was obtained in a relatively pure state.A nutrition and toxicity study was performed by feeding a semi-synthetic diet containing sandalwood seed oil to a level of 15% of total energy content to a group of mice for one month and another group for two months. The most significant effect of sandalwood seed oil ingestion when compared with a standard lab diet (5% fat, by weight) and a canola oil-enriched diet (15% fat, by weight) was an apparent reduction in body weight gain, which may be the effect of ximenynic acid as a growth retardant. Serum aspartate aminotransferase levels were determined in the mice as an indicator of hepatotoxicity. These levels were higher in mice fed the sandalwood seed oil diet than those fed the standard lab diet, suggesting that ximenynic acid may affect liver-specific enzyme activity. Analysis of the total lipid fatty acids of various tissues and organs of mice showed only a low incorporation of ximenynic acid into the general tissues (0.3-3% by weight), and its absence in the brain.This study suggests a few health benefits from consumption of large quantities of sandalwood seed oil in the diet. These include a low lipid content in blood, heart, muscle, increase in the 16:1/16:0 and 18:1/18:0 ratios, production of increased levels of 18:1 (n-9) and docosahexaenoic acid, and decreased levels of arachidonic acid in certain tissues. There were no specific pathological, morphological or mortality changes observed in the mice.Sandalwood seed may be both a food and a medicine.

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18

Hale, G. "The nature and binding properties of immobilized glycosaminoglycans on the endothelial surface : Studies in vivo and in vitro." Thesis, Bucks New University, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382511.

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19

Harfst, Elizabeth. "A biochemical and immunological study of cardiac gap junctions." Thesis, Imperial College London, 1990. http://hdl.handle.net/10044/1/46332.

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20

Lashley, Tammaryn. "BRI2 gene-related dementias : a morphological and biochemical study." Thesis, University College London (University of London), 2006. http://discovery.ucl.ac.uk/1444924/.

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Aspects of the neurodegenerative mechanism in AD remain unknown therefore studies on alternative models of cerebral amyloidosis, such as familial British dementia (FBD) and familial Danish dementia (FDD) may contribute to a better understanding of the neurodegenerative process. FBD and FDD are neurodegenerative disorders caused by mutations in the BRI2 gene. Both mutations cause elongation of the precursor proteins, the furin-like cleavage of which results in the formation of amyloidogenic peptides, ABri in FBD and ADan in FDD. Extensive morphological examinations of FBD and FDD were undertaken using antibodies recognising ABri and ADan, establishing a regional distribution of CNS peptide deposits in either amyloid or pre-amyloid configuration in both diseases, including cerebral amyloid angiopathy (CAA) formation. Amyloid associated proteins (AAP) are able to modify Afi aggregation and are implicated in AD pathogenesis. Establishing whether AAPs are implicated in the pathogenesis of other cerebral amyloidoses, AAP deposition was investigated and found associated with ABri and ADan amyloid and preamyloid parenchymal lesions. Inflammatory mechanisms, including activation of the complement pathways, initiated by AJ3 deposition strongly are implicated in AD pathogenesis. The presence of the complement pathways were shown in FBD and FDD, highlighting the importance of chronic inflammation in the neurodegenerative diseases. Biochemical analysis of extracted ABri and ADan species indicates that as solubility of the deposits decrease heterogeneity and complexity of extracted peptides increases, including post-translational modification of glutamate to pyroglutamate. The production and cellular origin of the precursor proteins and the localisation of fiirin expression were investigated. Evidence is presented that BRI2 mRNA and furin are found in neurons and glia, suggesting that cleavage of the wild type and mutated precursor proteins can take place in these cells. The absence of BRI2 mRNA in cerebrovascular cells indirectly supports the drainage hypothesis of CAA.

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21

Shen, Gang, and 沈剛. "Active mandibular forward positioning: a molecular and biochemical study." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B29821137.

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22

Franklin, Timothy G. "Biochemical and pharmacological study of the Mu-opioid receptor." Thesis, Loughborough University, 1990. https://dspace.lboro.ac.uk/2134/13414.

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23

Coghlan, David St John. "A biochemical study of the cellulases of Volvariella volvacea." Thesis, University of Nottingham, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240257.

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24

Wall, Rita Susan. "A structural and biochemical study of the corneal stroma." Thesis, Open University, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.257553.

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25

Danahey, Daniel Gerard. "A biochemical and immunohistochemical study of rat sertoli cells /." The Ohio State University, 1990. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487682558445099.

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Shen, Gang. "Active mandibular forward positioning : a molecular and biochemical study /." Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk/hkuto/record.jsp?B21415171.

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27

Mancini, Francesca. "Information theory in biochemical regulatory networks: a theoretical study." Doctoral thesis, SISSA, 2015. http://hdl.handle.net/20.500.11767/3906.

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In this Thesis we consider the optimization of information transmission as a viable design principle for biochemical networks. We apply this principle to a simple model regulatory circuit, given by an input and a delayed output that switch randomly between two states in continuous time. First we maximize the transmitted information in the network at a given output delay, when the system has no external constraints and it is in steady state or can optimize its initial condition. We find that optimal network topologies correspond to common biological circuits linked to stress response and that circuits functioning out of steady state may exploit absorbing states to be more informative than in steady state. We then take into account that biological regulatory networks need to dissipate energy in order to transmit biochemical signals and that such signaling often happens in challenging environmental conditions. Hence we explore the system's trade-offs between information transmission and energetic efficiency. At fixed delay and dissipated energy, we determine the most informative networks both in the absence and in the presence of feedback. We find that negative feedback loops are optimal at high dissipation, whereas positive feedback loops become more informative close to equilibrium conditions. Moreover, feedback allows the system to transmit almost the maximum available information at a given delay, even in the absence of dissipation. Finally, within a game-theoretic maximin approach, we ask how a biochemical network should be constructed to be most informative in the worst possible initial condition set by the environment. We find that, in the limit of large energy dissipation, the system tunes the ratio of the input and output timescales so that the environmental disturbance is marginalized as much as possible.

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Griffin, Damian Gerard. "A family-based study investigating the genetic basis of calcium-containing kidney stones." Thesis, University of Southampton, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368068.

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Wilkinson, P. "A clinical, genetic and biochemical study of hereditary spastic paraplegia." Thesis, University College London (University of London), 2007. http://discovery.ucl.ac.uk/1445184/.

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The hereditary spastic paraplegias (HSPs) represent a clinically and genetically heterogeneous group of neurological disorders. The phenotype is classified as pure or uncomplicated when the spastic paraparesis occurs in isolation and complicated when there are significant additional neurological or other clinical features. Inheritance may be autosomal dominant, autosomal recessive or X-linked. Twenty families from the UK were identified with autosomal recessive HSP. Clinical analysis of affected individuals demonstrated a variety of different phenotypes with a slight preponderance of complicated cases. Genetic linkage analysis in the largest of these families identified linkage to the previously described SPG5A locus with a maximum LOD score of 4.84. Marker saturation analysis subsequently refined the locus to a 23.6cM region on chromosome 8q. In 6 of the remaining families linkage to the SPG7 locus could not be excluded. An affected individual from each of these families and 29 sporadic HSP cases were subsequently screened for SPG7 gene mutations using a combination of SSCP and sequencing. Three sporadic patients were found to have compound heterozygous SPG7 mutations, five of which were novel and one that had been described previously. Muscle biopsies in two of the patients with SPG7 mutations failed to demonstrate histological evidence of oxidative phophorylation defects but did reveal mitochondrial respiratory chain complex I-III defects in muscle and complex I deficiency in cultured myoblasts. A similar combination of SSCP and sequencing was used to screen a group of 12 families with early onset autosomal dominant HSP for SPG3A gene mutations. Only the previously reported R239C mutation was identified in one family suggesting that SPG3A mutations are relatively uncommon in this population. Genome wide linkage analysis in a consanguineous Bedouin family from Kuwait with a complicated HSP phenotype including cognitive impairment, dysarthria and distal amyotrophy identified linkage to a 22.8cM interval on chromosome 12 with a maximum LOD score of 5.1. No coding sequence mutations were identied in the KIF5A gene, associated with pure autosomal dominant HSP, located within this region. This interval has therefore been proposed as a novel locus for complicated autosomal recessive HSP (SPG26).

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Stephanson, Niclas Nikolai. "Liquid chromatography-mass spectrometry study of two biochemical alcohol markers /." Stockholm, 2007. http://diss.kib.ki.se/2007/978-91-7357-141-8/.

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Wegrzyn, Renee Diane. "Genetic, biochemical, and physiological study of yeast prion protein aggregation." Diss., Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/25221.

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Bartlett, Michael Griffith. "Application of mass spectrometry to the study of biochemical processes." Diss., Georgia Institute of Technology, 1994. http://hdl.handle.net/1853/27426.

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Bastani, A. "Biochemical study of cytidine 3',5' cyclic monophosphate phosphodiesterase activity." Thesis, Swansea University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.636051.

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Two enzymes capable of hydrolysing cytidine 3',5'-cyclic monophosphate have previously been reported, one (cCMP-specific PDE) with an absolute specificity for cCMP as substrate, and the other (multifunctional PDE) capable of hydrolysing a number of cyclic nucleotide substrates. This phosphodiesterase preparation was capable of hydrolysing different substrates (cyclic CMP > cyclic AMP > cyclic UMP > cyclic GMP) with the highest specific activity toward cyclic CMP as substrate. It was found to contain both the multifunctional and the cyclic CMP-specific phosphodiesterase, as shown by kinetic data, mass spectrometric analysis, and by utilizing isoelectric focusing and polyacrylamide gel electrophoresis. The PDE activity of the preparation was activated by cytidine and mercaptoethanol, inhibited by aspartate and arginine, but was insensitive to calmodulin. It was active in the absence of metal ions but inhibited by addition of Fe2+ and Ca2+ when cyclic CMP was substrate. Various types of inhibition were observed with different effectors. Cyclic CDP-deoxy cyclic CMP, glutamyl cyclic CMP and 3',5'-cyclic AMP produced competitive inhibition; theophylline produced noncompetitive inhibition; and cytidine 2'-monophosphate 3',5'-cyclic monophosphate, 5-CMP, 2',3'-cyclic CMP, 2',3'-cyclic AMP and 3',5'-cyclic UMP produced mixed type inhibition (either competitive-noncompetitive or uncompetitive-noncompetitive inhibition). Molecular modelling of the substrates and effectors was carried out, and it was deduced that the nitrogen atom bonded to carbon atom 4 (N4) and the oxygen atom bonded to carbon atom 5'(5'-O) with an interatomic distance of 8.92A° was crucial to the binding of ligands; good correlation was obtained between this distance and the potency of the effector. Mass spectrometric analysis suggested that both 5'- and 3'-CMP were products of the enzyme preparation's activity upon 3',5'-cCMP.

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Bruce, Catherine R. "A proteomic and biochemical study of pathogenicity in Phytophthora infestans." Thesis, University of Aberdeen, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.430269.

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The work presented in this thesis uses proteomics and biochemical analyses to identify and investigate potential pathogenicity factors in Phytophthora infestans. Proteomics was also used to analyse the P. infestans-tomato (Lycopersicon esculentum) interaction. 2DGE was used to identify interaction specific proteins in intercellular wash fluid (IWF) from tomato leaves infected with P. infestans. Protein profiles of IWF from infected leaves were compared with profiles of IWF from healthy leaves. Interaction specific proteins were identified by MALDI-T of MS and PMF. Seven proteins of tomato origin were identified. Most proteins identified belong to pathogenesis-related (PR) protein families. This thesis also describes characterisation of an actin depolymerising factor termed PiADF1. PiADF1 was previously identified from mycelium culture filtrate separated by 2DGE. The actin cytoskeleton plays an important role in plant defence responses. It is proposed that PiADF1 may function in suppressing actin related host defence responses during the P. infestans-plant interaction. Secretion inhibition assays were carried out which support the hypothesis that PiADF1 is secreted by P. infestans despite lacking a classical N-terminal signal sequence. Gene expression analysis, fluorescence localisation in planta and phylogenetic analyses were also carried out. Possible roles for PiADF1 in suppression of host defence responses are discussed. A potential host cell targeting (HCT) peptide motif, RxLR was recently discovered in extracellular proteins of biotrophic oomycetes. This thesis describes initial attempts to identify proteins, which may be involved in RxLR-mediated HCT. Proteins which may form HCT machinery are speculated upon.

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Bohorquez-Restrepo, Andres. "BIOCHEMICAL AND COLORIMETRIC STUDY OF FLOWER COLOR IN PHLOX SPECIES." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1429694764.

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36

Ricci, Mario. "The marsupial sperm tail cytoskeleton : a morphological and biochemical study /." Title page, table of contents and abstract only, 2004. http://web4.library.adelaide.edu.au/theses/09PH/09phr4911.pdf.

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37

DESIDERIO, Doriana. "Biochemical approaches to study protein-ligand interaction for pharmacological applications." Doctoral thesis, Università degli studi del Molise, 2016. http://hdl.handle.net/11695/66366.

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Questo lavoro ha riguardato l’utilizzo di comuni tecniche biochimiche ottimizzate per lo studio delle interazioni proteina-ligando coinvolte in alcune patologie di frequente incidenza, quali il morbo di Alzheimer ed il cancro. Il morbo di Alzheimer è una patologia neurodegenerativa, progressiva ed irreversibile, caratterizzata principalmente da un’alterazione del sistema colinergico, con conseguente riduzione dei livelli del neurotrasmettitore acetilcolina (Ach), e dall’accumulo extracellulare di placche senili costituite soprattutto dal peptide β-amiloide (Aβ). Allo stato attuale delle conoscenze mediche non c’è ancora una cura definitiva per questa malattia; il trattamento si avvale di terapie farmacologiche di tipo sintomatico e palliativo, il cui scopo è quello di inibire sia le colinesterasi, onde ripristinare i livelli naturali dell’Ach, sia la β-secretasi 1 (BACE-1), per prevenire l'aggregazione del peptide Aβ. A tal fine, composti analoghi del Donepezil, farmaco attualmente utilizzato per le forme lieve e moderata del morbo di Alzheimer, sono stati identificati, mediante procedure di “docking” molecolare, e quindi sintetizzati, mediante procedure di sintesi “eco-friendly”. Per tutte le molecole sintetizzate, strutturalmente più rigide del Donepezil e caratterizzate da gruppi sostituenti differenti, è stato valutato i) l’effetto sull’attività dell’AChE, ii) la selettività nei confronti di BuChE, iii) l’effetto inibitorio sull’attività enzimatica di BACE-1 e iv) la tossicità su linee cellulari di neuroblastoma. Da questi esperimenti è risultato che tra tutti i composti sintetizzati solo due possono essere dei promettenti candidati per lo sviluppo di nuovi farmaci per il trattamento dell’Alzheimer, essendo caratterizzati da una duplice attività inibitoria, sia nei confronti di AChE che di BACE-1. La proteina p53 regola il ciclo cellulare e svolge la funzione di soppressore tumorale. La sua attività è regolata dalle proteine Minute Double Mourine (MDM) 2 e 4, meglio conosciute come MDM2 e MDMX, le quali agiscono nei confronti di p53 attraverso un meccanismo di tipo feedback negativo, legandosi al dominio idrofobico N-terminale della proteina. In effetti, un’interessante strategia per la terapia del cancro sarebbe ripristinare la funzionalità di p53 antagonizzando l’attività regolatrice negativa di MDM2/X. A tal fine, è stata ottimizzata la comune tecnica dell’elettroforesi in condizioni native, per lo studio dei complessi che l’oncosoppressore p53 forma con MDM2/MDMX. Tale tecnica sfrutta la differente mobilità elettroforetica delle proteine su gel di poliacrilammide in condizioni non denaturanti. Il vantaggio di utilizzare l’elettroforesi in condizioni native consiste nell’economicità e nella semplicità della metodica, a differenza dei metodi attualmente utilizzati per lo stesso tipo di analisi, quali ad esempio la tecnica NMR, la risonanza plasmonica di superficie o la fluorescenza polarizzata. Dagli esperimenti condotti, tale tecnica è risultata potenzialmente utile anche per uno screening delle molecole dotate di un potenziale potere farmacologico antitumorale. This work is focused on the application of simple biochemical techniques to study protein-ligand interaction involved in some diseases of frequent incidence, such as Alzheimer’s disease (AD) and cancer. The current therapies for AD, still symptomatic and palliative, from one side act to inhibit AChE, in order to restore the natural level of ACh, and, from the other side act as inhibitors of β-secretase 1 (BACE-1), useful to prevent the A aggregation. Under this regard, efforts have been recently devoted to the development of dual inhibitors of AChE and BACE-1. In this frame, donepezil-like compounds were synthesised, in order to identify novel effective drugs for the treatment of AD. For all these new synthesized analogues, more rigid and diversely substituted compared to donepezil structure, the inhibitor activity on AChE, the selectivity vs BuChE, the side-activity on BACE-1 and the effect on SHSY-5Y neuroblastoma cell viability were tested. Two potential new lead compounds for a dual therapeutic strategy against Alzheimer disease were envisaged. Activation of p53 tumor suppressor by antagonizing its negative regulators MDM2/X has been considered an attractive strategy for cancer therapy. Great effort has been given in the development of drugs able to dissociate the p53•MDM2/X complex. Under this regard, a simple and rapid technique to study the p53–MDM2/X interaction has been developed. This method is based on the different mobility between the interacting domains of the oncosuppressor p53 and its protein ligands MDM2/X on polyacrylamide gels under native conditions. While the two proteins MDM2/X alone were able to enter the gel, the formation of a binary complex between p53 and MDM2/X prevented the gel entry. The novel technique is reliable for determining the different affinity elicited by MDM2 or MDMX toward p53, and for analyzing the dissociation power exerted by small molecules on the complex taking advantage of the appearance of migrating MDM2 or MDMX, when inhibitors are added to the complex mixture. Despite the fact that some other different methods have been employed to study this kind of interaction, including NMR technology, surface plasmon resonance or fluorescence polarization, the relevance of the method here described resides in the fact that it is much more simple and it does not require any tagging/derivatization procedure of the protein fragments employed. This simple and rapid technique can be useful to easily discriminate, among a library of compounds endowed with a potential pharmacological activity against cancer development, the molecules with the highest dissociative potency, preventing the use of expensive and more sophisticated technologies.

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BRISCO, R. DI. "APPROACHES TO THE STUDY OF GLYCOLIPID BIOCHEMICAL MECHANISMS OF ACTION." Doctoral thesis, Università degli Studi di Milano, 2010. http://hdl.handle.net/2434/148879.

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With this work I want to give an explanation of the role of glycolipids in biological processes, paying particular attention to their involvement in various biochemical mechanisms. This thesis will be divided into two sections in which I discuss in the first one, the involvement of glycolipids in the process of fertilization and in the second one I will pay attention on a new class of glycolipids that might be involved in immunoregulation processes. In more details in the first section I will provide an overview of the biochemical role of sulfogactosylglicerolipid (SGG), present in the sperm head of different mammalian species, and its involvement in the process of fertilization. Then I will discuss an approach with which one can interfere in this biochemical mechanism focusing on the possibility of using a new class of molecules that permit not only the inhibition of the fertilization process but that can also act against sexually transmitted diseases. In this scenario, then I will focus on the characteristics of antimicrobial peptides, in particular on the family of cathelicidin, and on their possible application in the inhibition of fertilization, by interaction with SGG, and at the same time the prevention of sexually transmitted diseases. In the second section I will discuss on a new class of immunomodulating glycolipids with an atypical structure, produced by symbiotic bacteria in the marine sponge Plakortis Simplex, which releases a unique profile of cytokines. In this scenario, then I will talk about simplexide and on the role in which is involved in the activation of peripheral blood mononuclear cells (PBMC), and the peculiar profile of cytokines released. Then I will describe the synthesis of a fluorescent analogue of simplexide which will be made to evaluate the subcellular distribution of the glycolipid and to clarify its mechanism of action.

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BASILICO, FEDERICA. "A BIOCHEMICAL AND STRUCTURAL STUDY OF THE KINETOCHORE - CENTROMERE INTERFACE." Doctoral thesis, Università degli Studi di Milano, 2014. http://hdl.handle.net/2434/234139.

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Faithful chromosome segregation during mitosis requires the dynamic interaction between spindle microtubules and kinetochores, multiprotein complexes built on centromeres. A group of kinetochore proteins associates with centromeres throughout the cell cycle and is thus named constitutive centromere-associated network (CCAN). Biochemical and functional analyses indicate that CCAN proteins are organized in sub-complexes. However, the exact organization of these sub-complexes has not been fully elucidated to date. The aim of my project has been the biochemical reconstitution of CCAN sub-complexes and their structural and functional characterization. In particular, this dissertation dwells upon the results I have obtained regarding three different but intrinsically related topics. First, I present a biochemical and structural characterization of the CCAN protein CENP-M (centromere protein M), which displays the fold, but not the enzymatic activity of a G protein. In addition, I disclose its unprecedented role in the context of a quaternary complex with CENP-H, CENP-K and CENP-I and provide information about the spatial organization of this complex. The first steps towards an in vivo validation of these results are also described. Second, I report the discovery of a direct interaction of CENP-H / CENP-K complex with CENP-C. Third, I have been involved in establishing in the laboratory techniques for the in vitro reconstitution of recombinant nucleosomes. The production of material of good quality and quantity has recently been achieved, supporting the analysis of in vitro interactions between nucleosomes and kinetochore components. Specifically, I illustrate some preliminary observations concerning a direct interaction of Mis12 complex with nucleosomes.

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Al, Awam Khaled. "The study of biomarkers for psychiatric disorders and their potential application in clinical and forensic psychiatry." Thesis, Swansea University, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.678476.

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Shearman, M. S. "Pharmacological and biochemical characterisation of serotonin-5-HT2Ì² receptors from rat frontal cortex and human platelets." Thesis, University of Nottingham, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.377497.

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Ismaiel, M. O. "Biochemical and immunological studies of Bacteroides gingivalis trypsin-like protease and its role in periodontal disease." Thesis, University of Bristol, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.380225.

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Liu, Yandi. "A study of the biochemical development and toxicology of the seed of Santalum spicatum." Curtin University of Technology, School of Pharmacy, 1997. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=12031.

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The seed of Santalum spicatum is rich in a fixed oil (59% by weight), which is characterised by a high percentage of acetylenic, ethylenic ximenynic acid (35% of total fatty acids). A number of important aspects of the seed fixed oil, its composition in developing seeds, its triacylglycerols molecular species in the oil, the nutrition and toxicity of the oil feeding, and the possible bioactivity of ximenynic acid in mice were investigated.The identification of cis and trans isomers of ximenynic acid in the seed oil, and the metabolite of ximenynic acid in mouse liver lipid fractions were achieved using 2-amino-2-methyl-1-propanol to form 2-substituted 4,4-dimethyloxazoline derivatives, which were analysed by gas chromatography with mass spectrometric detection.Changes in proximate and fatty acid composition were investigated in developing seed collected weekly from about seven days after flowering to maturity. It was determined that moisture and carbohydrate contents decreased significantly during the development sequence, while fixed oil content increased from 0.3% to 50% (by weight) with seed development. A corresponding increase in the proportions of both oleic and ximenynic acids occurred suggesting a precursor/product relationship. Mature seed collected from different locations in Western Australia showed minor differences in characteristics and lipid composition, which may have been influenced by geographical origin and harvesting year of samples.The lipid components from the seed oil were separated using thin-layer chromatography and the individual triglyceride bands were characterised by high performance liquid chromatography and gas chromatography using flame ionisation and mass spectrometric detection after removal from the plate. The triximenynin (trisantalbin) band showed no other contaminating fatty acids and was obtained in a relatively pure state.A ++ nutrition and toxicity study was performed by feeding a semi-synthetic diet containing sandalwood seed oil to a level of 15% of total energy content to a group of mice for one month and another group for two months. The most significant effect of sandalwood seed oil ingestion when compared with a standard lab diet (5% fat, by weight) and a canola oil-enriched diet (15% fat, by weight) was an apparent reduction in body weight gain, which may be the effect of ximenynic acid as a growth retardant. Serum aspartate aminotransferase levels were determined in the mice as an indicator of hepatotoxicity. These levels were higher in mice fed the sandalwood seed oil diet than those fed the standard lab diet, suggesting that ximenynic acid may affect liver-specific enzyme activity. Analysis of the total lipid fatty acids of various tissues and organs of mice showed only a low incorporation of ximenynic acid into the general tissues (0.3-3% by weight), and its absence in the brain.This study suggests a few health benefits from consumption of large quantities of sandalwood seed oil in the diet. These include a low lipid content in blood, heart, muscle, increase in the 16:1/16:0 and 18:1/18:0 ratios, production of increased levels of 18:1 (n-9) and docosahexaenoic acid, and decreased levels of arachidonic acid in certain tissues. There were no specific pathological, morphological or mortality changes observed in the mice.Sandalwood seed may be both a food and a medicine.

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Gao, Honghai. "Biochemical study of endonuclease V and its application in mutation scanning." Connect to this title online, 2007. http://etd.lib.clemson.edu/documents/1181252071/.

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Moyer, Robert Walter. "Comparative morphological and biochemical study of the pineal complex in geckos /." Title page, abstract and contents only, 1998. http://web4.library.adelaide.edu.au/theses/09PH/09phm938.pdf.

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Bristow, David Ronald. "A biochemical study of the mammalian brain GABAâ†A receptor complex." Thesis, University of Cambridge, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.293201.

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Li, Yonghua. "A biochemical and molecular study of lipid biosynthesis in Mucor circinelloides." Thesis, University of Hull, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.395508.

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Nelson, John. "The mucopolysaccharidoses in Northern Ireland : a clinical, genetic and biochemical study." Thesis, Queen's University Belfast, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357486.

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Ma, Mingwen. "A study of the physiological and biochemical characteristics of liver spheroids." Thesis, University of the West of England, Bristol, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.407320.

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Behan, Moira Kathleen. "Homeoviscous adaptation to temperature and pressure. A biophysical and biochemical study." Thesis, University of Liverpool, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.279656.

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