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Comparative Degradation Of Emerging Pollutants Using Chemical And Enzymatic Approaches, Khadega Abobaker Al-Maqdi

Theses

Organic pollutants, especially those found in water bodies; pose a direct threat to various aquatic organisms as well as humans. A variety of different remediation approaches, including chemical and biological methods have been developed for the degradation of these organic pollutants. However, comparative mechanistic studies of pollutant degradation by these different systems are almost non-existent. In this study, the degradation of two emerging pollutants an antibiotic pollutant, Sulfamethoxazole (SMX) and a model thiazole pollutant, Thioflavin T (ThT), was carried out using advanced oxidation process (AOP), using UV+H2O2 or a peroxidase enzyme system. Optimization conditions for Sulfamethoxazole degradation by peroxidase enzyme …

Comparison Of Various Means Of Evaluating Molecular Electrostatic Potentials For Noncovalent Interactions, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

The various heterodimers formed by a series of Lewis acids with NH3 as Lewis base are identified. Lewis acids include those that can form chalcogen (HSF and HSBr), pnicogen (H2PF and H2PBr), and tetrel (H3SiF and H3SiBr) bonds, as well as H‐bonds and halogen bonds. The molecular electrostatic potential (MEP) of each Lewis acid is considered in a number of ways. Pictorial versions show broad regions of positive and negative MEP, on surfaces that vary with respect to either the value of the chosen isopotential, or their distance from the nuclei. Specific points are identified where the MEP reaches a …

New Synthetic Reactions Towards Global Chlorination And Enamides Functionalization, Mirza Ardella Saputra

LSU Doctoral Dissertations

This dissertation focuses on two main projects, global chlorination and enamide functionalization, which both encompass in cationic intermediates. Inspired by the desires to find a new chlorination method, global chlorination project is emphasized in chapter one and chapter two, in which chapter one details various known chlorine-containing natural products, including alkyl chlorides and vinyl chlorides. This chapter also describes the previously known protocols to synthesize alkyl chlorides in the attempts of chlorosulfolipids total syntheses, as well as several known reactions to synthesize vinyl chlorides that are both important functional groups in organic synthesis. Chapter two depicts our novel synthetic reaction …

Synthesis, Crystal Structure, And Photoluminescent Properties Of 3,3′,4,4′-Tetraethyl-5,5′-Divinyl-2,2′-Bipyrrole Derivatives, Toru Okawara, Reo Kawano, Hiroya Morita, Alan Finkelstein, Renjiro Toyofuku, Kanako Matsumoto, Kenji Takehara, Toshihiko Nagamura, Seiji Iwasa, Sanjai Kumar

Publications and Research

Photoluminescent divinylbipyrroles were synthesized from 3,3′,4,4′-tetraetyl-2,2′-bipyrrole-5,5′-dicarboxaldehyde and activated methylene compounds via aldol condensation.For mechanistic clarity, molecular structures of Meldrum’s acid- and 1,3-dimethylbarbituricacid-derived divinylbipyrroles were determined by single-crystal X-ray diffraction. Photoluminescentproperties of the synthesized divinylbipyrroles in dichloromethane were found to be dependent onthe presence of electron withdrawing groups at the vinylic terminal. The divinylbipyrroles derivedfrom malononitrile, Meldrum’s acid, and 1,3-dimethylbarbituric acid showed fluorescent peaks at553, 576, and 602 nm respectively. Computational studies indicated that the alkyl substituents on thebipyrrole 3 and 3′positions increased energy level of the highest occupied molecular orbital (HOMO)compared to the unsubstituted derivatives and provided rationale for the …

Organelle-Specific Single-Molecule Imaging Of Α4Β2 Nicotinic Receptors Reveals The Effect Of Nicotine On Receptor Assembly And Cell-Surface Trafficking, Ashley M. Fox-Lee, Faruk H. Moonschi, Christopher I. Richards

Chemistry Faculty Publications

Nicotinic acetylcholine receptors (nAChRs) assemble in the endoplasmic reticulum (ER) and traffic to the cell surface as pentamers composed of α and β subunits. Many nAChR subtypes can assemble with varying subunit ratios, giving rise to multiple stoichiometries exhibiting different subcellular localization and functional properties. In addition to the endogenous neurotransmitter acetylcholine, nicotine also binds and activates nAChRs and influences their trafficking and expression on the cell surface. Currently, no available technique can specifically elucidate the stoichiometry of nAChRs in the ER versus those in the plasma membrane. Here, we report a method involving single-molecule fluorescence measurements to determine the …

Responsive Nanogel Probe For Ratiometric Fluorescent Sensing Of Ph And Strain In Hydrogels, Mingning Zhu, Dongdong Lu, Shanglin Wu, Qing Lian, Wenkai Wang, Amir H. Milani, Zhengxing Cui, Nam T. Nguyen, Mu Chen, L. Andrew Lyon, Daman J. Adlam, Anthony J. Freemont, Judith A. Hoyland, Brian R. Saunders

Engineering Faculty Articles and Research

In this study a new pH-responsive nanogel probe containing a complementary nonradiative resonance energy transfer (NRET) fluorophore pair is investigated and its ability to act as a versatile probe of network-related changes in three hydrogels demonstrated. Fluorescent sensing using NRET is a powerful method for studying relationships between Angstrom length-scale structure and macroscopic properties of soft matter. Unfortunately, inclusion of NRET fluorophores into such materials requires material-specific chemistry. Here, low concentrations of preformed nanogel probes were included into hydrogel hosts. Ratiometric photoluminescence (PL) data for the gels labeled with the nanogel probes enabled pH-triggered swelling and deswelling to be studied …

Spectroscopic And Computational Studies Of Reversible O2 Binding By A Cobalt Complex Of Relevance To Cysteine Dioxygenase, Anne A. Fischer, Sergey V. Lindeman, Adam T. Fiedler

Chemistry Faculty Research and Publications

The substitution of non-native metal ions into metalloenzyme active sites is a common strategy for gaining insights into enzymatic structure and function. For some nonheme iron dioxygenases, replacement of the Fe(II) center with a redox-active, divalent transition metal (e.g., Mn, Co, Ni, Cu) gives rise to an enzyme with equal or greater activity than the wild-type enzyme. In this manuscript, we apply this metal-substitution approach to synthetic models of the enzyme cysteine dioxygenase (CDO). CDO is a nonheme iron dioxygenase that initiates the catabolism of L-cysteine by converting this amino acid to the corresponding sulfinic acid. Two mononuclear …

Kinetic Characterization Of Listeria Monocytogenes 2-C- Methyl-D-Erythritol 4-Phosphate Cytidylyltransferase ( Cms ) Enzymes Using High Performance Liquid Chromatography ( Hplc ), Mark Oblazny

Theses and Dissertations

Infectious diseases, with increasing prevalence of antibiotic resistant bacteria, coupled with the declining rate in discovery of antimicrobial agents, impose one of the most significant threats to human health. Here we identify 2-C-methyl-D-erythritol 4-phosphate cytidylyltransferase (CMS) as a valid target for antibiotic development which is an enzyme in pathogenic organisms that leads to the biosynthesis of isoprene precursor molecules. Isoprene molecules are one of nature’s most common building blocks that are vital to many biological metabolic processes and are synthesized via the mevalonic acid dependent (MVA), or methylerythritol phosphate (MEP) pathway. Vertebrates utilize the MVA pathway, while many pathogenic bacteria …

The Biochemical Assessment Of Two Secreted Acid Phosphatases From Leishmania Tarentolae, Their Response To Electric Fields, Glycosidase Incubation, And / Or Vanadium, Benjamin M. Dorsey

Theses and Dissertations

Leishmaniasis, as defined by the Center for Disease Control and Prevention, is a neglected tropical disease with 1.6 million new cases reported each year. However, there is yet to be safe, effective, and affordable treatments provided to those affected by this disease1. Still underappreciated as a potential pharmaceutical targets, especially for cutaneous leishmaniasis infections, are the two isozymes of secreted acid phosphatase (SAP); secreted acid phosphatase 1 (SAP1) and secreted acid phosphatase 2 (SAP2). These enzymes are involved in the survival of the parasite in the sand fly vector, and the prevention of host macrophages from forming parasitophorous vacuole and …

Synthesis, In Vitro Characterization And Applications Of Novel 8-Aminoquinoline Fluorescent Probes, Adonis Mcqueen

USF Tampa Graduate Theses and Dissertations

Malaria is a parasitic disease that is caused by the plasmodium parasite. Plasmodium infection has affected man for thousands of years. With advances in drug discovery over the past century, malaria has evolved to possess resistance to most mainline therapeutics. This war of drug discovery vs plasmodium evolution continues to be fought to this very day, with attempts to eradicate malaria worldwide. Frontline treatments such as chloroquine, artemisinin, and atovaquone/proguanil have all seen parasitic resistance in strains of P. vivax as well as P. falciparum. While plasmodium possesses resistance to most classes of anti-malarials, the 8-aminoquinoline (8-AQ) class has …

Investigating Potential Pollutant Sources Causing Lack Of Biodiversity In Lytle Creek And Indian Run, Audrey E. Mcgowin, Amira Alsenbel, Harry Mcvey, Lori Williams, Taylor Stuckert

Chemistry Faculty Publications

This report describes the results of research performed with funds from the Sture Fredrik Anliot Grant Fund granted in March 2016 and the Wright State University College of Science and Mathematics. The title of the grant was “Lytle Creek and Indian Run Sediment and Water Pollution Assessment” and its primary aim was to identify and measure pollutants that could be causing a lack of biodiversity in Lytle Creek in Wilmington, OH. The project formed the basis of Amira Alsenbel’s Masters in Chemistry thesis research.

Gum Arabic Promotes Oxidation And Ester Hydrolysis, Koen P. Vercruysse, Lauren E. Tyler, Jade Readus

Chemistry Faculty Research

We studied the interactions between gum Arabic and select catecholic compounds like caffeic acid, chlorogenic acid and catechol. We observed that GA is capable of promoting the auto-oxidation of the above-mentioned compounds into darkly colored pigments without the addition of redox-sensitive cations. Gum Arabic appeared to be unique among polysaccharide-based materials as many other types of polysaccharides promote the oxidation of the above-mentioned compounds only in the presence of redox cations like Fe2+ or Cu2+. RP-HPLC and SEC chromatographic techniques were employed to monitor the reactions and to observe the formation of high molecular mass, pigmented materials from gum Arabic …

Ligand Modulation Of Sidechain Dynamics In A Wild-Type Human Gpcr, Lindsay D. Clark, Igor Dikiy, Karen Chapman, Karin Ej Rodstrom, James Aramini, Michael V. Levine, George Khelashvili, Soren Gf Rasmussen, Kevin H. Gardner, Daniel M. Rosenbaum

Publications and Research

GPCRs regulate all aspects of human physiology, and biophysical studies have deepened our understanding of GPCR conformational regulation by different ligands. Yet there is no experimental evidence for how sidechain dynamics control allosteric transitions between GPCR conformations. To address this deficit, we generated samples of a wild-type GPCR (A2AR) that are deuterated apart from 1H/13C NMR probes at isoleucine d1 methyl groups, which facilitated 1H/13C methyl TROSY NMR measurements with opposing ligands. Our data indicate that low [Na+] is required to allow large agonist-induced structural changes in A2AR, and that patterns of sidechain dynamics substantially differ between agonist (NECA) and …

Computational Chemical Biology: From Atomistic Insights Towards Drug Design, Christo Christov

TechTalks

No abstract provided.

2-D Electrophoresis Modeling Of Multienzyme Cutting Of Polypeptides, Howard Mayes

Theses

2-Dimensional Electrophoresis is one of the tools in the identification of proteins by molecular weight and pH. The display of molecular weight allows the researcher to quickly identify whether a specific protein or peptide string is in the sample. The pH measurement allows even better resolution between different species in the sample. The MultiEnzyme ElectroPhoresis (MEEP) program tries to model that by providing a graph that displays separated protein strings by both molecular weight and pH. The ability to cleave the protein with 43 different enzyme variations allows the researcher to analyze appropriate enzymes to isolate a protein subsequence before …

First-Principles And Model Simulation Of All-Optical Spin Reversal, Thomas George, G.P. Zhang, Z. Babyak, Y. Xue, Y. Bai

Chemistry & Biochemistry Faculty Works

All-optical spin switching is a potential trailblazer for information storage and communication at an unprecedented fast rate free of magnetic fields. However, the current wisdom is largely based on semiempirical models of effective magnetic fields and heat pulses, so it is difficult to provide high-speed design protocols for actual devices. Here, we carry out a massively parallel first-principles and model calculation for 13 spin systems and magnetic layers, free of any effective field, to establish a simpler and alternative paradigm of laser-induced ultrafast spin reversal and to point out a path to a full-integrated photospintronic device. It is the interplay …

Development Of Novel Alkaloid Derivatives For The Treatment Of Chronic Myeloid Leukemia, Lindsay Michelle Renn

Theses and Dissertations

The majority of chronic myeloid leukemia (CML) patients can be treated with and respond to imatinib mesylate (Gleevec). Imatinib is known to inhibit BCR-ABLl kinase activity, and is effective for the treatment of the majority of CML patients. Multiple mutations have been found in patients resistant to imatinib treatment, including many located in the BCR-ABLl tyrosine kinase domain (e.g. E255K and T315I). Matrine is a bioactive alkaloid from Sophora flavescens and has been shown to inhibit several types of cancers and is used in Chinese medicine. The goal of this study is to develop new matrine derivatives that inhibit growth …

Thermochemistry Of Fluorinated Aldehydes And Corresponding Radicals;Thermochemistry And Kinetics Of Diethyl Ether And Ethyl Oxirane Relative To Reactions Under Atmospheric And Combustion Conditions, Douglas Lee Purnell Jr.

Dissertations

Fundamental thermochemical properties including enthalpies (ΔH°f 298), entropies (S°(T)), heat capacities (Cp(T)), and bond dissociation energies (BDEs) for several common and complex hydrocarbon fuel species are determined using computational chemical methods. ΔH°f 298 values are calculated using isodesmic reactions with the CBS-APNO, CBS-4M, CBS-QB3, G2, G3, G4, Weizmann-1 (W1U) and M06-2X, ωB97X, B3-LYP with basis set 6-31G+ (d,p) and 6-31G++(d,p) calculation methods. Structures, moments of inertia, vibrational frequencies, and internal rotor potentials are calculated for contributions to entropies and heat capacities. Kinetic rate parameters are calculated for hydrogen abstraction and …

Dietary Transfer Of Heavy Metals In Manatees, E. M. Smith, Dimitri Giarikos, A. Daniels, Amy Hirons

Chemistry and Physics Faculty Proceedings, Presentations, Speeches, Lectures

In recent decades, manatees and dugongs globally have exhibited potentially detrimental levels of a variety of heavy metals in their body tissues. The threatened Florida manatee (Trichechus manatus latirostris), which is a subspecies of the West Indian manatee (Trichechus manatus), has shown corresponding high levels of heavy metals in their blood, skin, liver, and kidneys. As obligate herbivores, these animals rely heavily upon seagrasses as a major component of their diet. Globally, seagrasses at low latitudes have high levels of heavy metals in their tissues. Detrimental levels of heavy metals in Sirenians have not been established …

North Pacific Marine Mammals Populations Rocked By Heavy Metal Concentrations, Pilar Ferdinando, Chitra Gotluru, Tanya Juneja, Kevin Cash, Karanja Sekou, Emily Pope, L. K. Duffy, Dimitri Giarikos, Amy Hirons

Chemistry and Physics Faculty Proceedings, Presentations, Speeches, Lectures

No abstract provided.

Ua66 Ogden College Of Science & Engineering Newsletter, Wku Ogden College Of Science & Engineering

Ogden College of Science & Engineering Publications

Newsletter created by and about Ogden College of Science & Engineering.

• Stevens, Cheryl. A Word with the Dean . . .
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• 3rd Annual Research Experience for Undergraduates Program Conference
• Into Bowling Green
• Barren RIver
• Mammoth Cave National Park
• Barrow, Alaska
• South Korea
• Postcards from the Field
• WKU Research Foundation
• Office of Research & Creative Activity
• About Applied Research & Technology Program
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Photochemical Generation And Kinetic Studies Of High-Valent Metal-Oxo Intermediates Supported By Corrole And Porphyrin Ligands, Ngo Fung Lee

Masters Theses & Specialist Projects

High-valent transition metal-oxo intermediates are of fundamental importance because of their central role as active oxidizing species in enzymatic and synthetic catalytic oxidations. Many transition metal catalysts have been extensively studied as models of the ubiquitous cytochrome P450 enzymes to probe the sophisticated oxygen atom transfer mechanism as well as to invent enzyme-like oxidation catalysts.

In this work, photolysis of highly photo-labile corrole-manganese(IV) bromates or nitrites by visible light was studied in two corrole systems with different electronic environments. The corrole systems under studied include 5,10,15- tris(pentafluorophenyl)corrole (TPFC) and 5,10,15-triphenylcorrole (TPC). As observed in both systems, homolytic cleavage of O-Br …

A Near-Global Atmospheric Distribution Of N2o Isotopologues, Peter F. Bernath, Mahdi Yousefi, Eric Buzan, Chris D. Boone

Chemistry & Biochemistry Faculty Publications

The distributions of the four most abundant isotopologues and isotopomers (N₂O, ¹⁵NNO, N¹⁵NO, and NN¹⁸O of nitrous oxide have been measured in the Earth's stratosphere by infrared remote sensing with the Atmospheric Chemistry Experiment (ACE) Fourier transform spectrometer. These satellite observations have provided a near-global picture of N₂O isotopic fractionation. The relative abundances of the heavier species increase with altitude and with latitude in the stratosphere as the air becomes older. The heavy isotopologues are enriched by 20-30% in the upper stratosphere and even more over the poles. These observations are …

Ruthenium Catalyzed Deaminative Coupling Reaction Of Amines Via C-N Bond Activation, Pandula T. Kirinde Arachchige

Master's Theses (2009 -)

C–N bond activation via transition-metal catalyst has attracted much attention during the past two decades. This strategy has become one of the most promising way to generate secondary amines, which are very important in a broad spectrum of applications in pharmaceutical industry, synthetic organic chemistry and material science. The secondary amines can be utilized as an important synthetic intermediate for further manipulations. The in-situ formed catalytic system generated from the tetranuclear Ru–H complex with 4-(1,1-dimethylethyl)-1,2-benzenediol ligand was found to be effective for the synthesis of secondary amines from the direct deaminative coupling of amines. The ruthenium catalyst was highly effective …

Spectral Characterization Of Cytochromes P450 Active Sites Using Nmr And Resonance Raman Spectroscopy, Remigio Usai

Dissertations (1934 -)

The Cytochrome P450 (P450s) has been the subject of intense research for over six decades. An efficient approach for isotopic labeling of the prosthetic group in heme proteins was exploited to produce an analogue of the soluble bacterial cytochrome P450cam (P450cam) that contains a 13C labeled-protoheme prosthetic group. HU227 strain of E. coli, which lacks the δ-aminolevulinic acid (δ-ALA) synthase gene, was employed in the heterologous expression of P450cam harboring a prosthetic group labeled with 13C at the Cm and Cα positions by growing cells in the presence of [5-13C] δ-ALA, which was synthesized in four steps from [2-13C] glycine. …

Nucleotide-Dependent Preferential Localization Of Ras In Model Membranes With Lipid Raft Nanodomains, Anna Shishina

Dissertations (1934 -)

Membrane proteins constitute a third of all proteins in the cell and more than 50% of drug targets. However, the analysis of membrane proteins has many challenges owing to their partially hydrophobic surfaces, flexibility and lack of stability. One example of an essential membrane protein is Ras superfamily. Ras is a small monomeric GTPase involved in regulation of cell growth, proliferation and differentiation. Therefore, Ras and its effectors are among the most important targets for cancer therapy. A detailed knowledge of the processes occurring during signal propagation via Ras might help to elucidate the mechanisms of the involved signal cascades. …

Racemic And Enantiopure Forms Of 3‐Ethyl‐3‐Phenylpyrrolidin‐2‐One Adopt Very Different Crystal Structures, Arcadius V. Krivoshein, Sergey V. Lindeman, Tatiana V. Timofeeva, Victor N. Khrustalev

Chemistry Faculty Research and Publications

3‐Ethyl‐3‐phenylpyrrolidin‐2‐one (EPP) is an experimental anticonvulsant based on the newly proposed α‐substituted amide group pharmacophore. These compounds show robust activity in animal models of drug‐resistant epilepsy and are thus promising for clinical development. In order to understand pharmaceutically relevant properties of such compounds, we are conducting an extensive investigation of their structures in the solid state. In this article, we report chiral high‐performance liquid chromatography (HPLC) separation, determination of absolute configuration of enantiomers, and crystal structures of EPP. Preparative resolution of EPP enantiomers by chiral HPLC was accomplished on the Chiralcel OJ stationary phase in the polar‐organic mode. Using …

Selenium Distribution And Cycling In The Eastern Equatorial Pacific Ocean, Zoe Wambaugh

OES Theses and Dissertations

Oxygen minimum zones in oceanic waters have become increasingly important to the marine environment and society. Low oxygen waters affect not only the distribution and abundance of marine organisms, but also impact the solubility and transport of trace elements that are of biological importance, with the chemical speciation and solubility depending on the actual redox poise of the waters. One redox sensitive trace element of interest is selenium, which can be both toxic and essential for organisms, depending on its chemical speciation. In 2013, the US GEOTRACES program completed the GP16 transect from Peru to Tahiti, going through the oxygen …

Synthesis, Characterization And Application Of Sugar-Based Low Molecular Weight Gelators, Ifeanyi Simeon Okafor

Chemistry & Biochemistry Theses & Dissertations

Low molecular weight gelators (LMWGs) are an interesting class of compound that have gained considerable attention especially because of their potential applications for soft biomaterials. Carbohydrate based low molecular weight hydrogelators and organogelators are able to selfassemble and form ordered supramolecular structures, which are useful for exploring biomedical applications. The resulting gelators are responsive to external stimuli because of the weak noncovalent intermolecular forces and interaction that influences self-assembly. Stimuli-responsive supramolecular organogels with interesting properties in response to external environmental stimuli have gained considerable attention due to their applications in biomaterials, sensors and for drug delivery.

One of the major …

Characterization Of The Ornithine Hydroxylation Step In Albachelin Biosynthesis, Kendra Bufkin, Pablo Sobrado

Chemistry Faculty Research & Creative Works

N-Hydroxylating monooxygenases (NMOs) are involved in siderophore biosynthesis. Siderophores are high affinity iron chelators composed of catechol and hydroxamate functional groups that are synthesized and secreted by microorganisms and plants. Recently, a new siderophore named albachelin was isolated from a culture of Amycolatopsis alba growing under iron-limiting conditions. This work focuses on the expression, purification, and characterization of the NMO, abachelin monooxygenase (AMO) from A. alba. This enzyme was purified and characterized in its holo (FAD-bound) and apo (FAD-free) forms. The apo-AMO could be reconstituted by addition of free FAD. The two forms of AMO hydroxylate ornithine, while lysine increases …