Physical Sciences and Mathematics Commons^™

Characterization Of Cytidylyltransferase Enzyme Activity Through High Performance Liquid Chromatography, James Brault

Theses and Dissertations

The cytidylyltransferases are a family of enzymes that utilize cytidine 5â?? triphosphate (CTP) to synthesize molecules that are precursors to membrane phospholipids. There are four well known enzymes: CTP: phosphoethanolamine cytidylyltransferase (ECT), CTP: glycerol-3-phosphate cytidylyltransferase (GCT), 2-C-methyl-D-erythritol-4-phosphate cytidylyltransferase synthetase (CMS), and CTP: phosphocholine cytidylyltransferase (CCT). Previously, a radioisotope tagging method was employed to study cytidylyltransferase catalysis. Using CCT as a model, a method utilizing high performance liquid chromatography (HPLC) was developed to replace the radioisotope scintillation technique. The development of this new HPLC method is cheaper, more efficient, and more accurate than the previously established method.

The targets of separation …

Arylboronates As H2o2 Or Photo-Inducible Dna Cross-Linking Agents: Design, Synthesis, Mechanism, And Anticancer Activity, Yibin Wang

Theses and Dissertations

Interest in the development of cancer therapies with improved selectivity and reduced host toxicity has been growing. In this thesis, we designed and synthesized a series of novel non-toxic arylboronic ester and biarylboronic ester derivatives that can be activated by hydrogen peroxide (H2O2) to induce DNA interstrand cross-link formation. The mechanism of DNA cross-linking induced by these arylboronates involves generation of phenol intermediates 1 followed by departure of leaving group (L) leading to quinone methides (QMs) 2, which directly cross-link DNA via alkylation. The QM formation is the rate-determining step for DNA cross-linking. The activity and selectivity of these compounds …

Image-Charge Detection €“ Novel Instrumentation And Applications, Brandon Lee Barney

Theses and Dissertations

Image-charge detection is an analytical technique in which a highly-charged particle is detected by the magnitude of the image current that it generates in a detecting electrode. This current is represented as a voltage between the charged particle and the sensing electrode. It is a single particle detection method, ideal for the analysis of large, variable mass particles such as biological cells. Some of the physical properties of Bacillus subtilis spores were explored using different applications of image-charge detection. B. subtilis is a gram-negative spore-forming bacteria that has been shown to exhibit extremophile behavior. The particular extremophile behavior that was …

Mechanistic Study Of Heme Protein-Mediated Nitric Oxide Dioxygenation Using Photolytically Produced Nitric Oxide, Karl Joseph Koebke

Theses and Dissertations

The previously reported NO precursor [Mn(PaPy2Q)(NO)]ClO4 (1), where (PaPy2QH) is N,N-bis(2-pyridylmethyl)-amine-N-ethyl-2-quinoline-2-carboxamide, was synthesized and proven capable of producing as much as 180 µM NO when irradiated by a single 3 mJ 500nm laser pulse, in a 0.15 cm path cell, without the need for additional sacrificial reductants or oxidants. Species 1 was first used to study the reaction of nitric oxide with oxy-myoglobin (oxyMb) to form ferric myoglobin (metMb) and nitrate. This reaction had long been assumed to proceed via the same iron-bound peroxynitrite intermediate (metMb(OONO)) as the metMb-catalyzed isomerization of peroxynitrite to nitrate. Recent research showed that the metMb-catalyzed …

Histone Deacetylase 6 (Hdac6) Is Critical For Tumor Cell Survival And Promotes The Pro-Survival Activity Of 14-3-3Ζ Viadeacetylation Of Lysines Within The14-3-3Ζ Binding Pocket, Jeffrey Benjamin Mortenson

Theses and Dissertations

Our understanding of non-histone acetylation as a means of cellular regulation is in its infancy. Using a mass spectrometry approach we identified acetylated lysine residues and monitored acetylation changes across the proteome as a consequence of metabolic stress (hypoxia). We observed changes in acetylation status of non-histone lysines in tumor cells. Through the use of small molecule inhibitors of histone deacetylase enzymes (HDACs) and siRNA screening identified HDAC6 as a pro-survival regulator of lysine acetylation during hypoxia. The phospho-binding protein 14-3-3ζ acts as a signaling hub controlling a network of interacting partners and oncogenic pathways. We show here that lysines …

Analytical Approaches In Investigating The Kinetics Of Water-Molecule Complexes In Tropospheric Reactions, William J. Keeton

Theses and Dissertations

Ozone is a heavily monitored pollutant. Ozone is not directly emitted into the atmosphere, but rather the product of chemical reactions. Ground level ozone occurs when nitrogen oxides (NOx) and volatile organic compounds (VOCs) react with each other in the presence of sunlight. The primary precursors of ozone are anthropogenically emitted, and as a result, tropospheric ozone has cost millions of dollars in damages and has hurt the health of countless people. This dissertation is a collection of work that aims to provide insight into atmospheric reactions that result in tropospheric ozone and the instrumentation to study such reactions. While …

An Approach To An Agave Problem: The Bioremediation Of Agricultural Waste By Yeast Fermentations, Joshua Michael Jarodsky

Theses and Dissertations

The agricultural waste products created by industries, such as the Tequila manufacturing industry, create thousands of tons of waste material every year. This agricultural waste often becomes an environmental and ecological problem for fields and surrounding areas. The purpose of this study is to determine the potential of using the yeast Kluyveromyces marxianus 7-1 and Kluyveromyces marxianus 8-1 to ferment the leaf waste from the harvesting of the Agave tequilana as a form of bioremediation. Fermentations (anaerobic, under constant shaking, and at room temperature) were monitored for colony forming units, pH of fermentation broth, concentration of reducing sugars, and protein …

A Study Of Allylic Aminations As Catalyzed By Heterobimetallic Pd-Ti Complexes, Diana Lauren Ellis

Theses and Dissertations

Heterobimetallic complexes present a unique approach to catalyzing challenging reactions. By having two metals in close proximity to each other, the metals are able to interact and alter their electronics in a way that simple organic ligands (carbon, nitrogen, sulfur etc.) cannot. Our studies of heterobimetallic complexes focus on a Pd–Ti complex. The complex features a dative interaction between the palladium and the titanium held together by a phosphonamide scaffold. This interaction increases the electrophilicity of the palladium and makes it a very suitable catalyst for allylic amination reactions. We have conducted extensive studies of this catalyst in allylic aminations, …

Application Of Coumarin Derivatives In Dna-Associated Study: Mutation Detection, Site-Specific Labeling, Photoinduced Interstrand Cross-Links And Ligation Reactions, Huabing Sun

Theses and Dissertations

Coumarin derivatives have been widely utilized as cross-linking agents in polymer science, being fluoroprobes in biochemistry and as medicines in pharmacy. But the coumarin's fluorogenic properties and reactivities in DNA were rarely reported and unclear, which limits its bioapplications due to possible side reactions towards biomolecules. In this thesis, we investigated the activity of coumarin moiety towards natural DNA and expanded its application in DNA-associated study. We have found that coumarin derivatives can serve as perfect DNA cross-linking agents, as alkylation agents for site-specific labeling, and fluoroprobes for single nucleotide polymorphism (SNP) analysis, which provided a novel insight of biotoxicity …

Synthesis And Characterization Of Carbonized Poly (Divinylbenzene) Microspheres For Carbon/Nanodiamond/Polymer-Based Core-Shell Materials And Applications Of This Mixed-Mode Phase To High-Performance Liquid Chromatography, Chuan-Hsi Hung

Theses and Dissertations

This work focuses on improving the quality of carbon-based core-shell materials for high performance liquid chromatography (HPLC) via the characterization of the core materials, and also the development of chromatographic methods (separations) for them. In the early part of this work, I applied organic synthesis to make uniform, spherical poly(divinylbenzene) (PDVB) microspheres, and then carbonized them to prepare carbon core materials for core-shell particle synthesis. Here, I studied in detail the surface and material properties of these particles with multiple instruments, which allowed me to describe the physical and chemical changes that took place during each treatment. The uniform, spherical …

Immunoassays Of Potential Cancer Biomarkers In Microfluidic Devices, Jayson Virola Pagaduan

Theses and Dissertations

Laboratory test results are important in making decisions regarding a patient's diagnosis and response to treatment. These tests often measure the biomarkers found in biological fluids such blood, urine, and saliva. Immunoassay is one type of laboratory test used to measure the level of biomarkers using specific antibodies. Microfluidics offer several advantages such as speed, small sample volume requirement, portability, integration, and automation. These advantages are motivating to develop microfluidic platforms of conventional laboratory tests. I have fabricated polymer microfluidic devices and developed immunoassays on-chip for potential cancer markers. Silicon template devices were fabricated using standard photolithographic techniques. The template …

Functional Expression And Characterization Of A Truncated Candida Antarctica Lipase B In Yeast, Samantha Robinson

Theses and Dissertations

Candida antarctica lipase B is an enzyme capable of hydrolyzing ester bonds in a lipid-water interface with potential to become a useful biocatalyst for production of biodiesel fuel. Enzymatically catalyzing the transesterification of triacylglycerides to produce fatty acid alkyl esters (biodiesel) is an environmentally cleaner alternative to the current process which utilizes chemical reagents as catalysts. Optimization and development of strains to express highly active, stable, large quantities of these biocatalysts is essential for inexpensive production of biodiesel. Additionally, lipase enzymes can be immobilized onto a resin, eliminating the need to recover the catalyst from the product and allowing multiple …

Fluorescence Imaging Of Analyte Profiles In An Inductively Coupled Plasma With Laser Ablation As A Sample Introduction Source, Lance Moses

Theses and Dissertations

Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) has risen to among the top tier techniques for the direct analysis of solid samples. However, significant problems remain that must be solved to achieve the full analytical potential of LA-ICP-MS. Inefficient conversion of aerosol to ions within the ICP or transmission through the MS interface may decrease precision, sensitivity, and/or accuracy. Although fundamental mechanisms that govern ion production and transmission have been studied extensively in solution-nebulization (SN) ICP-MS instruments, significant gaps in our understanding remain. Furthermore, it is unclear to what extent differences between the aerosols generated during SN and LA …