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Post-Translational Regulation Of Superoxide Dismutase 1 (Sod1): The Effect Of K122 Acylation On Sod1'S Metabolic Activity, Courtney Jean Banks

Theses and Dissertations

Many mutations in superoxide dismutase 1 (SOD1) cause destabilization and misfolding of the protein and are implicated in amyotrophic lateral sclerosis. Likewise, a few post-translational modifications (PTMs) on SOD1 have been shown to cause the same phenotype. However, relatively few PTMs on SOD1 have been studied in depth and, in particular, very few studies have demonstrated how these PTMs affect SOD1's various biological roles. SOD1 is traditionally known for its role in reactive oxygen species (ROS)-scavenging but has also been found to have a few other biological roles, including transcription factor activity to promote genomic stability, preservation of cytoskeletal activity, …

A Novel Method For Synthesis Of Hydroxytyrosol, Emmanuel Onobun

Electronic Theses and Dissertations

Hydroxytyrosol, 3,4-dihydroxyphenolethanol, a naturally occurring polyphenol most common in olive tree (Olea europaea), is one of the most effective member of the polyphenols family, because of its remarkable antioxidant activity, its ability to inhibit oxidation of low density lipids (LDL), and its protection against DNA oxidative damage. Hydroxytyrosol, which is widely used in cosmetics and food supplements industries, can be purchased as an olive oil extract that contains low concentration of hydroxytyrosol besides other polyphenols. The price and low natural abundance of hydroxytyrosol make alternative synthetic sources very attractive. In this research, a novel method for the synthesis of pure …

Nanostructured Functional Materials For Advanced Three-Dimensional (3d) Solar Cells, Jared Jaksik, H. Justin Moore, Tarek Trad, Okenwa Okoli, M. Jasim Uddin

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

Advancements in dye-sensitized solar cell (DSSC) technology are occurring at an ever-increasing rate, as the development of novel carbon-based materials, the increasing research into new 3D surface morphologies and cell design, and the focus on the development of new sensitizers and electrolytes have allowed many new possibilities for DSSCs. Solar cells that are three-dimensionally structured offer significant advantages over traditional crystalline / semi-crystalline panels in that they can convert incident photons that strike them at large incident angles, can be flexible / used in applications which require non-rigid materials, and can be substantially cheaper to produce than traditional panels, especially …

Cellulose Reinforced Thermoplastic Composites By In-Situ Ring-Opening Polymerization, Shahab Kashani Rahimi

Dissertations

Over the past two decades, the increasing concern about the negative environmental impacts of synthetic materials has led to rising interests in utilizing renewable natural resources to develop polymer materials with comparable properties and performance to their synthetic counterparts. One of the major fields of interest is polymer composites where the replacement of synthetic fibers with bio renewable natural fibers is of great potential. However, the processing difficulties, in terms of fiber dispersion and thermal stability have limited the application of cellulosic fibers to polymers with low processing temperatures which are mostly hydrophobic polymers. As a result, the true reinforcing …

Aryl Transfer Selectivity In Metal-Free Reactions Of Unsymmetrical Diaryliodonium Salts, David Stuart

Chemistry Faculty Publications and Presentations

Aromatic rings are found in a wide variety of products, including pharmaceuticals, agrochemicals, and functional materials. Diaryliodonium salts are novel reagents used to transfer aryl groups under both metal-free and metal-catalyzed reactions and thereby synthesize arene-containing compounds. This review focuses on recent studies in selective aryl transfer reactions from unsymmetrical diaryliodonium salts under metal-free conditions. Reactions reported from 2008 to 2017, which represents a period of significant growth in diaryliodonium salt chemistry, are presented and organized by the type of reactive intermediate formed in the reaction. Specifically, reactions involving λ³-iodane, λ³-iodane radical anions, aryl radicals, and …

Novel Design Strategies For Platinum-Containing Conjugated Polymers And Small Molecules For Organic Solar Cells, Wenhan He

Chemistry and Chemical Biology ETDs

Current state-of-the-art organic solar cells (OSCs) adopt the strategy of using conjugated polymers or small molecules as donors and fullerene derivatives as acceptors in their active layers. Regarding to the donors of interest, the conjugated polymers and small molecules coupled with heavy metals have been less explored compared to their counterparts. Among various transition metal complexes applied, Pt(II) complexes are unique because of their intrinsic square planar geometries and ability to serve as building blocks for conjugated systems. Furthermore, the heavy metal Pt facilitates the formation of triplet excitons with longer life times through spin-orbital coupling which are of benefit …

Estimation Of Bubble-Mediated Air–Sea Gas Exchange From Concurrent Dms And Co2 Transfer Velocities At Intermediate–High Wind Speeds, Thomas G. Bell, Sebastian Landwehr, Scott D. Miller, Warren J. De Bruyn, Adrian H. Callaghan, Brian Scanlon, Brian Ward, Mingxi Yang, Eric S. Saltzman

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Simultaneous air–sea fluxes and concentration differences of dimethylsulfide (DMS) and carbon dioxide (CO2/ were measured during a summertime North Atlantic cruise in 2011. This data set reveals significant differences between the gas transfer velocities of these two gases (1kw/ over a range of wind speeds up to 21ms􀀀1. These differences occur at and above the approximate wind speed threshold when waves begin breaking. Whitecap fraction (a proxy for bubbles) was also measured and has a positive relationship with 1kw, consistent with enhanced bubble-mediated transfer of the less soluble CO2 relative to that of the more soluble DMS. However, the correlation …

Development Of Entrapment Columns For The Study Of Affinity Based Analysis Of Drug–Protein Interactions, Shiden T. Azaria

Department of Chemistry: Dissertations, Theses, and Student Research

High-performance affinity chromatography (HPAC) is a type of liquid chromatography in which solutes are separated based on their binding to a stationary phase that is a biologically-related agent. Because of the strong and selective nature of many biological interactions, this method has already become a powerful technique for the purification and analysis of solutes that are complementary to the immobilized binding agent. Human serum albumin (HSA), the most abundant protein in the blood with concentrations of 35-50 mg/mL in serum, has interactions with many drugs, which can affect the absorption, distribution, metabolism and excretion of such agents.

The overall goal …

Real-Time Sensing Of Single-Ligand Delivery With Nanoaperture-Integrated Microfluidic Devices, W. Elliott Martin, Ning Ge, Bernadeta R. Srijanto, Emily Furnish, C. Patrick Collier, Christine A. Trinkle, Christopher I. Richards

Chemistry Faculty Publications

The measurement of biological events on the surface of live cells at the single-molecule level is complicated by several factors including high protein densities that are incompatible with single-molecule imaging, cellular autofluorescence, and protein mobility on the cell surface. Here, we fabricated a device composed of an array of nanoscale apertures coupled with a microfluidic delivery system to quantify single-ligand interactions with proteins on the cell surface. We cultured live cells directly on the device and isolated individual epidermal growth factor receptors (EGFRs) in the apertures while delivering fluorescently labeled epidermal growth factor. We observed single ligands binding to EGFRs, …

Ismar / Rmcmr 2017 Abstract Book - Joint Conference Of The International Society Of Magnetic Resonance, The Rocky Mountain Conference On Epr, And The Rocky Mountain Conference On Magnetic Resonance

Rocky Mountain Conference on Magnetic Resonance

Abstracts from the 59th annual meeting of the Rocky Mountain Conference on Magnetic Resonance, hosted jointly with the International Society of Magnetic Resonance and the Rocky Mountain Conference on EPR. Held in Quebec City, Canada, July 23-28, 2017.

Chelator-Free Radiolabeling Of Serrs Nanoparticles For Whole-Body Pet And Intraoperative Raman Imaging, Matthew A. Wall, Travis Shaffer, Stefan Harmsen, Darjus-Felix Tschaharganeh, Chun-Hao Huang, Scott W. Lowe, Charles Michael Drain, Moritz F. Kircher

Publications and Research

A single contrast agent that offers whole-body non-invasive imaging along with the superior sensitivity and spatial resolution of surface-enhanced resonance Raman scattering (SERRS) imaging would allow both pre-operative mapping and intraoperative imaging and thus be highly desirable. We hypothesized that labeling our recently reported ultrabright SERRS nanoparticles with a suitable radiotracer would enable pre-operative identification of regions of interest with whole body imaging that can be rapidly corroborated with a Raman imaging device or handheld Raman scanner in order to provide high precision guidance during surgical procedures. Here we present a straightforward new method that produces radiolabeled SERRS nanoparticles for …

Review: New Frontiers In Metabolomics: From Measurement To Insight, Eli Riekeberg, Robert Powers

Robert Powers Publications

Metabolomics is the newest addition to the “omics” disciplines and has shown rapid growth in its application to human health research because of fundamental advancements in measurement and analysis techniques. Metabolomics has unique and proven advantages in systems biology and biomarker discovery. The next generation of analysis techniques promises even richer and more complete analysis capabilities that will enable earlier clinical diagnosis, drug refinement, and personalized medicine. A review of current advancements in methodologies and statistical analysis that are enhancing and improving the performance of metabolomics is presented along with highlights of some recent successful applications.

Oligo(Ethylene Glycol)-Sidechain Microgels Prepared In Absence Of Cross-Linking Agent: Polymerization, Characterization And Variation Of Particle Deformability, Nicole Welsch, L. Andrew Lyon

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

We present a systematic study of self-cross-linked microgels formed by precipitation polymerization of oligo ethylene glycol methacrylates. The cross-linking density of these microgels and, thus, the network flexibility can be easily tuned through the modulation of the reaction temperature during polymerization. Microgels prepared in absence of any difunctional monomer, i.e. cross-linker, show enhanced deformability and particle spreading on solid surfaces as compared to microgels cross-linked with varying amounts of poly(ethylene glycol diacrylate) (PEG-DA) in addition to self-crosslinking. Particles prepared at low reaction temperatures exhibit the highest degree of spreading due to the lightly cross-linked and flexible polymer network. Moreover, AFM …

Cellular And Molecular Targets Of Menthol Actions, Murat Oz, Eslam El Nebrisi, Keun-Hang Susan Yang, Frank Christopher Howarth, Lina T. Al Kury

Mathematics, Physics, and Computer Science Faculty Articles and Research

Menthol belongs to monoterpene class of a structurally diverse group of phytochemicals found in plant-derived essential oils. Menthol is widely used in pharmaceuticals, confectionary, oral hygiene products, pesticides, cosmetics, and as a flavoring agent. In addition, menthol is known to have antioxidant, anti-inflammatory, and analgesic effects. Recently, there has been renewed awareness in comprehending the biological and pharmacological effects of menthol. TRP channels have been demonstrated to mediate the cooling actions ofmenthol. There has been new evidence demonstrating thatmenthol can significantly influence the functional characteristics of a number of different kinds of ligand and voltage-gated ion channels, indicating that at …

An Integrated Bioinformatic/Experimental Approach For Discovering Novel Type Ii Polyketides Encoded In Actinobacterial Genomes, Wubin Gao

Chemistry and Chemical Biology ETDs

Discovery of new natural products (NPs) is critical both for diseases treatment and crops protection. Numerous NP biosynthetic gene clusters (BGCs) in sequenced microbial genomes allow identification of new NPs through genome mining. Developing an integrated bioinformatic/experimental approach for discovering novel type II polyketides (PK-IIs) facilitates investigation of this family of NPs in an efficient, systematic way. Here, we developed an approach to analyze ketosynthase α/β (KSα/β) gene sequences to predict PK-II core structures, allowing us to target novel PK-II BGCs either from isolated genomic DNA or genomes from the NCBI databank, and to isolate novel PK-IIs produced by these …

31p Nmr Study Of Gtp-Cation Interactions, Zhiyan Song, Destiny L. Allen, Olarongbe Olubajo, Chellu S. Chetty

Georgia Journal of Science

Guanosine 5'-triphosphate (GTP) plays a pivotal role in many biologi­cal processes. The interactions of cations with GTP are essential to the stabilization of this nucleotide and the regulation of its functions. In this study, we present solution ³¹P NMR data on GTP samples in varied salt concentrations or pHs. From chemical shifts and T₁ , T₂ relaxations, it is concluded that the interaction strengths of cations with GTP are in the order of Ca²⁺ > Mg²⁺ > Li⁺ > Na⁺ for the cations, and in the order of beta > gamma > alpha for the phosphate groups. An …

Chemical Tools For Delivery Of Carbon Monoxide, Lisa Berreau

Funded Research Records

No abstract provided.

Magnetic Nanostructure Application In Sers Detection Of Melatonin And Resonance Raman Characterization Of Binding Of Catechol Moieties With Antibiotic, Siqi Sun

USF Tampa Graduate Theses and Dissertations

Raman spectroscopy provides characteristic peaks of the target molecules that can be observed with appropriate laser, spectrometer and detector. These characteristic peaks can reveal ‘fingerprint’ information of a molecule even in a myriad of cases and combinations. It makes Raman spectroscopy a highly sensitive and selective analytical technique. Raman spectroscopy has a variety of chemical, environmental and biological applications. In this dissertation, modified Raman method are applied in life sciences and pharmaceutical studies.

The major challenge against development of Raman spectroscopy is how to improve the intensity of Raman signal. Surface Enhance Raman Scattering (SERS) and resonance Raman(RR) are utilized …

Systematic Elucidation Of Factors That Influence The Strength Of Tetrel Bonds, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

Quantum calculations are used to examine the properties of heterodimers formed by a series of tetrel-containing molecules with NH₃ as universal Lewis base. TH₄ was taken as a starting point, with T= C, Si, Ge, and Sn. The H atoms were replaced by various numbers of F atoms: TH₃F, TF₃H, and TF₄ so as to monitor the effects of adding electron-withdrawing substituents. Unsubstituted TH₄ molecules form the weakest tetrel bonds, only up to about 2 kcal/mol. The bond is strengthened when the H opposite NH₃ is replaced by F, rising up …

Rational Drug Design Directed At Blocking The Initial Signaling Events In Lipopolysaccharide-Induced Sepsis., Christopher A. Tipton

Theses

Systemic Inflammatory Response Syndrome (SIRS) is classified as an immune system response to an infectious state. If left untreated, SIRS leads to sepsis, septic shock, end-organ dysfunction, and death. As a patient progresses through these stages, associations of acute respiratory distress, disseminated intravascular coagulation, and acute renal failure persist, resulting in millions of deaths annually. Lipopolysaccharide (LPS), a bacterial endotoxin, is released into the blood stream, triggering SIRS. LPS is found in the outer cell-wall of Gram-negative bacteria and is responsible for initiation of a devastating cytokine storm. One of the regions of LPS, lipid A, is a polyacylated glucosamine …

Chemical Investigations Of Fungal Natural Products For Drug Discovery, Danielle H. Demers

USF Tampa Graduate Theses and Dissertations

Natural products have, historically, played an important role in drug discovery. Nevertheless, drug resistance, pathogen evolution, and global climate change threaten human health and nearly all current anti-infective treatments on the market today. It is undeniable that new drug discovery efforts are needed with increasing urgency.

Bolstered by a rich history of discovering treatments in the world around us, natural products chemists continue to look to the environment with increasing understanding and emerging technologies that allow efficient, effective isolation of new chemical entities. This thesis will describe one such endeavor.

Focusing on fungal natural products, herein is described the isolation …

Mechanism-Informed Refinement Reveals Altered Substrate-Binding Mode For Catalytically Competent Nitroreductase, Warintra Pitsawong, Chad A. Haynes, Ronald L. Koder, David W. Rodgers, Anne-Frances Miller

Chemistry Faculty Publications

Nitroreductase from Enterobacter cloacae (NR) reduces diverse nitroaromatics including herbicides, explosives and prodrugs, and holds promise for bioremediation, prodrug activation and enzyme-assisted synthesis. We solved crystal structures of NR complexes with bound substrate or analog for each of its two half-reactions. We complemented these with kinetic isotope effect (KIE) measurements elucidating H-transfer steps essential to each half-reaction. KIEs indicate hydride transfer from NADH to the flavin consistent with our structure of NR with the NADH analog nicotinic acid adenine dinucleotide (NAAD). The KIE on reduction of p-nitrobenzoic acid (p-NBA) also indicates hydride transfer, and requires revision of …

Hydrogenation Of Organic Matter As A Terminal Electron Sink Sustains High Co2:Ch4 Production Ratios During Anaerobic Decomposition, Rachel M. Wilson, Malak M. Tfaily, Virginia I. Rich, Jason K. Keller, Scott D. Bridgham, Cassandra Medvedeff Zalman, Laura Meredith, Paul J. Hanson, Mark Hines, Laurel Pfeifer-Meister, Scott R. Saleska, Patrick Crill, William T. Cooper, Jeff P. Chanton, Joel E. Kostka

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Once inorganic electron acceptors are depleted, organic matter in anoxic environments decomposes by hydrolysis, fermentation, and methanogenesis, requiring syntrophic interactions between microorganisms to achieve energetic favorability. In this classic anaerobic food chain, methanogenesis represents the terminal electron accepting (TEA) process, ultimately producing equimolar CO₂ and CH₄ for each molecule of organic matter degraded. However, CO₂:CH₄ production in Sphagnum-derived, mineral-poor, cellulosic peat often substantially exceeds this 1:1 ratio, even in the absence of measureable inorganic TEAs. Since the oxidation state of C in both cellulose-derived organic matter and acetate is 0, and CO₂ has …

Unraveling The Coulombic Forces In Electronically Decoupled Bichromophoric Systems During Two Successive Electron Transfers, Maxim V. Ivanov, Shriya Wadumethrige, Denan Wang, Rajendra Rathore

Chemistry Faculty Research and Publications

Coulombic forces are vital in modulating the electron transfer dynamics in both synthetic and biological polychromophoric assemblies, yet quantitative studies of the impact of such forces are rare, as it is difficult to disentangle electrostatic forces from simple electronic coupling. To address this problem, the impact of Coulombic interactions in the successive removal of two electrons from a model set of spirobifluorenes, where the interchromophoric electronic coupling is nonexistent, is quantitatively assessed. By systematically varying the separation of the bifluorene moieties using model compounds, ion pairing, and solvation, these interactions, with energies up to about 0.4 V, are absent at …

Diversifying Homogenous Au(I)-Catalysis Through New Reaction Discovery, Stephen Motika

USF Tampa Graduate Theses and Dissertations

Homogenous Au(I)-catalysis has become a valuable synthetic tool to activate a host of unsaturated carbon functional groups towards nucleophilic addition. Over the course of the past two decades, many have embarked on new journeys within this field. Notably, the advancements in this field hinge on the development of new ligand systems that impart novel reactivity at the metal. Our group has focused on this area, as we have successfully demonstrated the utility of 1,2,3-triazoles as ligands for gold and a host of other transition metals and Lewis acids. With respect to gold catalysis, these ligands enhance the stability of the …

Structure And Activity Of Metallo-Peptides, Christian C. Tang

USF Tampa Graduate Theses and Dissertations

Metal ions are ubiquitously found in all living systems and play vital roles in supporting life forms by performing an array of biological activities. Such biological activities include binding and transforming organic molecules, and also acting as active centers and cofactors for catalysis of various acid-base and redox reactions in biological system. The main focus in bioinorganic chemistry is to elucidate the structural and functional roles of metals in biological systems. Among all transition metal ions, Cu²⁺ and Fe³⁺ are especially versatile and important due to their abilities to go through redox efficiently.

This dissertation can be divided …

Synthesis,Structure And Properties Of Ruthenium Polypyridyl Metalloligand Based Metal-Organic Frameworks, Mamatha Polapally

Masters Theses & Specialist Projects

Metal-organic frameworks (MOFs) have been extensively studied because of their amazing applications in gas storage, purification, photocatalysis, chemical sensing, and imaging techniques. Ruthenium polypyridyl complexes have been broadly considered as photosensitizers for the conversion of solar energy and photoelectronic materials. With this aspect, we have synthesized three new ruthenium polypyridyl based MOFs ([Ru(H2bpc)Cu(bpc)(Hbpc)2(H2O)]·5H2O (1), [Ru(H2bpc)(Fe(bpc)(Hbpc)2(H2O)2]·6H2O (2) and [Ru(H2bpc)Ni(bpc)(Hbpc)2(H2O)2]·6H2O (3)) from ruthenium(III) chloride, bpc (2,2’- bipyridine-4,4’-dicarboxylic acid) ligand, and 3d M(II) metal ions (M(II)= Cu(II), Fe(II), Ni(II)). These MOFs were synthesized under hydro or solvothermal conditions by using water, ethanol or methanol as solvents. The crystal structures of the new compounds …

Graphene-Based ‘Hybrids’ As High-Performance Electrodes With Tailored Interfaces For Alternative Energy Applications: Synthesis, Structure And Electrochemical Properties, Mayme Marie Van Meveren

Masters Theses & Specialist Projects

Technological progress is determined to a great extent by developments of novel materials from new combinations of known substances with different dimensionality and functionality. We investigate the development of 3D ‘hybrid’ nanomaterials by utilizing graphene based systems coupled with transition metal oxides (e.g. manganese oxides MnO2 and Mn3O4). This lays the groundwork for high performance electrochemical electrodes for alternative energy owing to their higher specific capacitance, wide operational window and stability through charge-discharge cycling, environmental benignity, cost effective, easily processed, and reproducible in a larger scale.

Thus far, very few people have investigated the potential of combining carbon sheets that …

Analysis Of Beverages By Total Reflection X-Ray Fluorescence, Martina Schmeling

Chemistry: Faculty Publications and Other Works

In advance of the Denver X-Ray Conference, we asked leading scientists who will be speaking at the conference about current trends and advances in X-ray fluorescence and X-ray diffraction. Here, these investigators discuss their work to advance these techniques and the sample preparation for such analyses, in areas such as photonics for telecommunications, steel structures, metals in pharmaceuticals, and imaging.

Understanding The Surface Fouling Mechanism Of Ultrananocrystalline Diamond Microelectrodes Using Microfluidics For Neurochemical Detection, An-Yi Chang

Doctoral Dissertations

Electrochemical methods are widely used for chronic neurochemical sensing, but thus far, the organic solution redox reactions fouled the electrodes' surface. It caused the reduction of sensitivity and the electrodes' lifetime.

Here, we present the boron-doped nanocrystalline diamond microelectrodes (BDUNCD) as the next generation electrode material for neurochemical sensor development. To aid in long-term chronic monitoring of neurochemicals, they have a wide window of electrochemical potential, extremely low background current, and excellent chemical inertness. The main research goal is to reduce the rate of electrode fouling due to the reaction by-products, and significantly extend their useful lifetime.

We systematically characterize …