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Phosphorylation Of Cytoskeletal Proteins By Protein Kinase C, David William Litchfield
Phosphorylation Of Cytoskeletal Proteins By Protein Kinase C, David William Litchfield
Digitized Theses
Protein kinase C is the Ca{dollar}\sp{lcub}2+{rcub}{dollar}/phospholipid-dependent enzyme that serves as the receptor for, and is directly activated by, the tumour-promoting phorbol esters. To examine the involvement of protein kinase C in the regulation of the organization or function of the actin-containing microfilaments, the activity of the enzyme towards two distinct groups of proteins that are thought to be involved in microfilament regulation has been investigated. For these studies, protein kinase C was partially purified from bovine brain or was more extensively purified from rat brain. Two proteins that are localized in certain areas of microfilament-membrane attachment (focal contacts), vinculin and …
Characterization Of The Specific Pyruvate Transport System Of Escherichia Coli K12, Verna Josephine Lang
Characterization Of The Specific Pyruvate Transport System Of Escherichia Coli K12, Verna Josephine Lang
Digitized Theses
A mutant of Escherichia coli K12 lacking pyruvate dehydrogenase and phosphoenolpyruvate synthase was used to study transport of pyruvate by whole cells. Uptake of pyruvate is maximal with mid-log phase cells and the Michaelis constant for transport is 20{dollar}\mu{dollar}M. Pretreatment of the cells with respiratory chain poisons or uncouplers, with the exception of arsenate, inhibits transport of pyruvate by up to 95%. Lactate and alanine, natural analogs of pyruvate, competitively inhibit transport only at very high concentrations. The synthetic analogues 3-bromopyruvate and pyruvic acid methyl ester are good competitive inhibitors.;In order to further minimize metabolism of pyruvate, membrane vesicles of …
A Photoelectron Study Of The Bonding Ability Of Phosphine And Isocyanide Ligands In Organometallic Complexes, Lisa Marie Dignard
A Photoelectron Study Of The Bonding Ability Of Phosphine And Isocyanide Ligands In Organometallic Complexes, Lisa Marie Dignard
Digitized Theses
High resolution ultraviolet photoelectron spectra of substituted tungsten carbonyl derivatives have been measured. The study of the photoelectron peaks due to the tungsten 5d orbitals in the series of complexes (W(CO){dollar}{lcub}\rm\sb{lcub}n{rcub}L\sb{lcub}6-n{rcub}{rcub}{dollar}) has demonstrated that the Ligand Additivity Model holds for the systems where L are tertiary phosphine ligands. This work confirms that the splitting of the tungsten 5d orbitals observed in the photoelectron spectra can be described in terms of ligand field effects and are not dominated by relaxation effects.;The substituent effects of methyl and phenyl groups in isocyanide and tertiary phosphine ligands have been studied by photoelectron, infrared and …
Base Excision Repair Of Dna In Human Cells: The Apurinic/Apyrimidinic Intermediate, Michael Francis Moran
Base Excision Repair Of Dna In Human Cells: The Apurinic/Apyrimidinic Intermediate, Michael Francis Moran
Digitized Theses
Base excision repair of DNA and factors that affect DNA incision in human cells were considered in this study.;Treatment of alkylated HeLa cells with 3-aminobenzamide, and inhibitor of poly(ADP-ribose) polymerase, increased the number of DNA strand breaks but did not slow down their rejoining by DNA repair. Therefore, an increase in DNA incision, not a decrease in ligation, results from the inhibition of poly(ADP-ribose) polymerase in alkylated cells. This is consistent with recent findings by others that suggest that repair-patch frequency is increased in alkylated cells when polyADP-ribosylation is inhibited.;Apurinic/apyrimidinic (AP) sites were measured in HeLa cells by digestion of …
A Major Cell Envelope Protein Of Escherichia Coli K12: Purification And Properties, Douglas Arthur Kuntz
A Major Cell Envelope Protein Of Escherichia Coli K12: Purification And Properties, Douglas Arthur Kuntz
Digitized Theses
The isolation and characterization of a major cell envelope protein from E. coli K12, the so-called "succinate eluted protein" (SEP) is reported. SEP was released by EDTA-sucrose and osmotic shock treatments, or during the formation of spheroplasts. The protein was purified on columns of aspartate-Sepharose (A-S) an affinity matrix previously used for the isolation of dicarboxylate transport components. SEP was the major protein eluted when the A-S columns were equilibrated in low ionic strength buffer (10 mM phosphate containing 5 mM EDTA). SEP was purified to apparent homogeneity as judged by SDS-PAGE, IEF and HPLC/gel filtration. SEP stimulated succinate transport …
The Role Of Lipids In The Structure And Function Of Yeast Membranes, Dennis John Fantin
The Role Of Lipids In The Structure And Function Of Yeast Membranes, Dennis John Fantin
Digitized Theses
Considerable attention has focused on the relationships that may exist between membrane lipids and membrane-associated enzyme activities. To explore these associations and to provide a better understanding of the role that lipids play in membrane function, a study was undertaken using Saccharomyces cerevisiae as a model system to study the lipid-protein interactions of membrane-bound enzymes. Using nutritional supplementation, the membrane level of ergosterol was increased which resulted in increased membrane tolerance against hyperthermia. Yeast mutants cho1 and opi3-3, defective in specific enzymes in the phospholipid biosynthetic pathway, were employed to study the effect of altered membrane phospholipid levels on the …
Surface Photochemistry: Semiconductor Mediated Reactions, Anthony Montague Draper
Surface Photochemistry: Semiconductor Mediated Reactions, Anthony Montague Draper
Digitized Theses
The semiconductor photoinduced valence isomerizations of several strained saturated hydrocarbons were investigated. Particularly, the radical cation rearrangements of quadricyclane and bishomocubane on ZnO and CdS were explored with respect to various experimental conditions; solvent, light intensity, temperature and presence of oxygen. A kinetic treatment of the data obtained revealed that bimolecular processes at the surface may occur by two routes: reaction between two adsorbed species, the Langmuir-Hinshelwood model and reaction of an adsorbed molecule with a molecule in solution, an Eley-Rideal type process. Unimolecular reaction at the surface was adequately described by only considering adsorbed substances. The square root relationship …
Synthesis And Mechanism In Organic Sulfonyl Chemistry, Kishan Chand Khemani
Synthesis And Mechanism In Organic Sulfonyl Chemistry, Kishan Chand Khemani
Digitized Theses
This thesis describes four topics in synthesis and mechanism of reactions of certain organo-sulfonyl compounds. The first describes the reaction of thiirane-1,1-dioxide with hydroxide ion. Notwithstanding an earlier report, it was found that the major product of this reaction was ethanesulfonate anion, substituted analogues of which have occasionally been observed as products of certain Ramberg-Backlund reactions. It is proposed that the reaction proceeds via a penta-coordinated sulfur intermediate formed by the attack of hydroxide ion at the sulfonyl function of thiirane-1,1-dioxide.;In the second study, use of {dollar}\sp{lcub}18{rcub}{dollar}O labels and kinetics led to the conclusion that hydrolysis of 2-hydroxyethanesulfonyl chloride to …
Hormonal Control Of Carbohydrate Metabolism In The American Cockroach, Periplaneta Americana L, Veeresh Lingam Sevala
Hormonal Control Of Carbohydrate Metabolism In The American Cockroach, Periplaneta Americana L, Veeresh Lingam Sevala
Digitized Theses
Hormonal control of trehalose synthesis in the fat body of the cockroach, Periplaneta americana, is accompanied by a large decrease in the flux of metabolites through the glycolytic pathway. The decrease in glycolytic flux was investigated by measuring time-dependent changes in the concentrations of glycolytic intermediates at various times after treating the fat body with corpus cardiacum (CC) extract. The data indicate that the CC stimulates trehalose synthesis by a mechanism which includes inhibition of the glycolytic pathway.;The concentration of glucose 6-phosphate in fat body which had been treated with CC extract increased by 360 percent after 30 min, whereas …
Applications Of Monoclonal Antibodies To Studies Of Structure/Function Relationships In Escherichia Coli F(1)-Atpase, Richard Gerard Tozer
Applications Of Monoclonal Antibodies To Studies Of Structure/Function Relationships In Escherichia Coli F(1)-Atpase, Richard Gerard Tozer
Digitized Theses
Twenty-one monoclonal antibodies to Escherichia coli F{dollar}\sb 1{dollar}-ATPase were characterized and used in structural studies of the enzyme. Solid phase competition assays placed antibodies recognizing the same or overlapping epitopes into competition subgroups. Immunoprecipitation and membrane-binding studies identified those antibodies recognizing external epitopes on soluble and membrane-bound forms of the holoenzyme and demonstrated that the {dollar}\delta{dollar} and {dollar}\epsilon{dollar} subunits are substantially exposed in F{dollar}\sb 1{dollar}F{dollar}\sb 0{dollar}.;Analysis of partially cleaved {dollar}\alpha{dollar} subunit using Western blots mapped antibody epitopes to its carboxyl-half. Analysis of CNBr/weak acid cleaved {dollar}\beta{dollar} located the non-inhibitory B-II antibody epitopes between Asp-345 and Met-380 and the inhibitory B-I …
Gas Phase Photoelectron Studies Using Helium(I), Helium(Ii) And Synchrotron Radiation, Jo-Ann Edith Bice
Gas Phase Photoelectron Studies Using Helium(I), Helium(Ii) And Synchrotron Radiation, Jo-Ann Edith Bice
Digitized Theses
High resolution He {dollar}{lcub}\rm I{rcub}\alpha{dollar} and He {dollar}{lcub}\rm II{rcub}\alpha{dollar} photoelectron spectra of the gas phase indium (I) and indium (III) halides have been obtained. The In 4d spectra of the indium (I) halides exhibited fine structure splitting due to the combined effects of spin-orbit coupling and ligand field splitting. The absence of any resolvable ligand field splitting in the In 4d spectra of indium (III) iodide and indium (III) bromide indicated that these compounds were dimeric in the gas phase. MS-X{dollar}\alpha{dollar} calculations were performed on both the indium (I) and indium (III) halides.;The inclusion of relativistic corrections to MS-X{dollar}\alpha{dollar} calculations …
Part I Total Synthesis Of (+,-)-Hirsutene Part Ii Photochemical And Photophysical Properties Of N-Benzoylindoles, Bimsara Wijesekara Disanayaka
Part I Total Synthesis Of (+,-)-Hirsutene Part Ii Photochemical And Photophysical Properties Of N-Benzoylindoles, Bimsara Wijesekara Disanayaka
Digitized Theses
Part One. The synthesis of polycyclic compounds usually requires various synthetic approaches to construct the required carbon skeletons. This thesis describes a sequence which leads to the preparation of the tricylo (6.3.0.{dollar}0\sp{lcub}2,6{rcub}{dollar}) undecane skeleton found in a number of physiological fungal metabolites. The key steps in this sequence are photochemical cycloaddition of the enol of 5,5-dimethylcyclohexane-1,3-dione to a cyclopentene, followed by intramolecular reductive coupling of the dione with a low valence titanium compound. A formal synthesis of the fungal metabolite hirsutene is described using this procedure. The route involves the photochemical (2+2) cycloaddition of 5,5-dimethylcyclohexane-1,3-dione to 2-methyl-2-cyclopentenol, followed by the …