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Elastin-Like Polypeptide Fusion Tag As A Protein-Dependent Solubility Enhancer Of Cysteine-Knot Growth Factors, Tamina L. Johnson

USF Tampa Graduate Theses and Dissertations

Elastin-like peptide (ELP) fusions promote therapeutic delivery and efficacy. Recombinant proteins, like neurotrophins, lack bioavailability, have short in vivo half-lives, and require high manufacturing costs. Fusing recombinant proteins with genetically encodable ELPs will increase bioavailability, enhance in vivo solubilization, as well as provide a cost-effective method for purification without the need for chromatography. During expression of neurotrophin-ELP (N-ELP) fusions, dense water-insoluble aggregates known as inclusion bodies (IBs) are formed. Inclusion bodies are partially and misfolded proteins that usually require denaturants like Urea for solubilization. Strong denaturants arrest ELPs stimuli-responsive property and increase unwanted aggregation, making purification difficult, yet possible. The …

Effects Of Enhanced Efficiency Nitrogen Fertilizers On Agronomic Parameters And Loss Pathways In The Subtropical Mississippi Delta Region, Scott Michael Pensky

LSU Master's Theses

Minimizing nitrogen (N) loss is critical for improving N use efficiency (NUE) in crop production and reducing its effects on the environment. Management practices such as seasonal application timing of N fertilizers and the addition of enhanced efficiency N fertilizers (EENFs) were investigated for the high N requirement of the two most common cereal crops globally, corn (Zea mays L.) and wheat (Triticum aestivum L.), in the subtropical climate of Louisiana. Field research was established during the 2016 and 2017 seasons at the LSU Agricultural Center’s Dean Lee and Central research stations to examine the effect of different EENFs and …

Evaluation Of Controlled-Release Nitrogen And Potassium Fertilizer In Louisiana Sugarcane Production, Samuel Kwakye

LSU Master's Theses

Sugarcane (Saccharum spp) production is an integral part of Louisiana's economy. Proper fertilizer management, particularly nitrogen (N) and potassium (K), optimizes sugarcane production. An experiment was established in 2015 at the LSU AgCenter Sugar Research Station in St. Gabriel, Louisiana to: (1) assess the effect of N and K fertilizer sources on sugarcane yield and quality parameters, and (2) monitor the changes in inorganic N and K levels in the soil at different sugarcane growth stages. The experiment was arranged in a randomized complete block design on a Sharkey clay soil and complete randomized design on a Commerce …

An Integrated Approach To Studying And Engineering Bacterial Type Ii Polyketide Core Structure Biosynthesis, Xuechen Zhu

Chemistry and Chemical Biology ETDs

Natural products including alkaloids, phenylpropanoids, polyketides, terpenoids and antibiotics provide abundant resources for drugs and drug leads. Type II polyketides (PK-IIs) are a large array of aromatic polyketides that have exhibited various bioactivities including anti-tumor, anti-cancer, anti-fungal and anti-bacteria. Based on the lengths of carbon chains and the cyclization patterns in their core structures, most bacterial PK-IIs have been classified into 6 typical classes: benzoisochromanequinone (BIQ), anthracycline (ANT), angucycline (ANG), tetracycline (TET), tetracenomycin (TCM) and pentangular (PEN). Bioengineering for diversification of PK-II core structures will generate libraries of bioactivities, which can serve the drug discovery in this family of compounds. …

Synthesis Of Novel Agents For The Treatment Of Infectious And Neurodegenerative Diseases, Benjamin Joe Eduful

USF Tampa Graduate Theses and Dissertations

Infectious and neurodegenerative diseases continue to be a major concern worldwide. In spite of the great advances in drug therapy for treating various infectious and neurodegenerative diseases, there is still an urgent need for new and improved drugs due to increasing drug resistance among pathogens, emergence of new pathogens, ease of transmission of infections, ineffective available treatments, toxicity associated with current standard of care, aging populations and the lack of better alternative treatment options.

The first part of this manuscript (chapters 1 - 5) describes the synthesis of novel agents active against Leishmania donovani. According to the World Health Organization …

Factors Affecting The Association Of Single- And Double-Stranded Rnas With Montmorillonite Nanoclays, A. Gujjari, B. V. Rodriguez, J. Pescador, Corina Maeder, G. W. Beall, L. K. Lewis

Chemistry Faculty Research

Montmorillonite (MMT) nanoclays exist as single and stacked sheet-like structures with large surface areas that can form stable associations with many naturally occurring biomolecules, including nucleic acids. They have been utilized successfully as vehicles for delivery of both drugs and genes into cells. Most previous studies have focused on interactions of MMT with DNA. In the current study, we have investigated the binding of small RNAs similar to those used for RNA interference (RNAi) therapy to two major forms of the clay, Na-MMT and Ca-MMT. Association of both forms of MMT with several double-stranded RNAs (dsRNAs), including 25mers, 54mers and …

Biomimetic Studies Of Oxidation Reactions By Metalloporphyrins Through Ligand Effect And Kinetic Studies Of Photo-Generated Porphyrin-Iron(Iv)- Oxocompound Ii Models, Dharmesh J. Patel

Masters Theses & Specialist Projects

High-valent iron(IV)-oxo porphyrins are the central oxidizing species in hemecontaining enzymes and synthetic oxidation catalysts. Many transition metal complexes have been extensively studied as models of the ubiquitous cytochrome P450 enzymes to probe the sophisticated oxygen atom transfer (OAT) mechanism as well as to invent enzyme-like oxidation catalysts. In this work, two metalloporphyrin complexes have been successfully synthesized, and spectroscopically characterized. A new photochemical entry to porphyrin-iron(IV)-oxo derivatives, commonly referred to as compound II models, was also investigated in two porphyrin ligands that differ in electronic and steric environments. As determined by their distinct UV-vis spectra and kinetic behaviors, iron(IV)-oxo …

Untargeted Bioassay Strategy For Medicinal Plants: In Vitro Antidiabetic Activity And 13c Nmr Profiling Of Extracts From Vitex Negundo L, Fabian M. Dayrit, Myrnille Joy B. Zabala, Lolita G. Lagurin

Chemistry Faculty Publications

Bioassay-guided fractionation is the principal method for the identification of active constituents in medicinal plants. By design, this method aims to identify the most active compound in a complex mixture with the objective of discovering novel drug candidates. Described here is a complementary method for the identification of known bioactive compounds in medicinal plants which is untargeted and which takes advantage of the large NMR database of known natural products and availability of statistical software. This untargeted bioassay strategy is demonstrated as a proof of principle in the determination of the antidiabetic compounds in Vitex negundo L. Crude methanol and …

Magnetic Properties Of Acenes And Their O-Quinone Derivatives: Computer Simulation, A. A. Starikova, A. G. Starikov, R. M. Minyaev, Alexander I. Boldyrev, V. I. Minkin

Chemistry and Biochemistry Faculty Publications

Quantum chemical study (DFT UB3LYP/6-311++G(d,p)) of the structure and properties of acenes functionalized with two o-benzoquinone groups and their complexes with sodium cations has been performed. An increase in the number of fused rings has been shown to result in the stabilization of biradicaloid state of acenes and the switching of the character of exchange interactions between redox-active moieties from antiferromagnetic to ferromagnetic. The obtained results allow one to consider o-quinone acene derivatives as a basis for designing magnetoactive compounds.

Do Paraben Derivatives Alter T Cell Immunity?, Hailey Kintz

Spring Presentation of Undergraduate Research

T cells immunity is linked to a complex system of cytokines that determine differentiation of naïve T cells into Th1, Th2, Th17, and Treg cells. Estrogen production or periods of elevated production have been correlated with an anti-inflammatory state in which Th2 and Treg cells are up-regulated. Such responses in the immune system are capable of supporting pre-cancerous activity. We are investigating the tie between the xenoestrogen compounds found in cosmetics, parabens, and their ability to regulate T cell immunity. Testing parabens and paraben derivatives with weaker estrogen receptor association will allow for a better understanding of the interplay between …

Detection Of Amyloid Beta (Aβ) Oligomeric Composition Using Matrix-Assisted Laser Desorption Ionization Mass Spectrometry (Maldi Ms)., Jasmine S-H Wang, Shawn N Whitehead, Ken K-C Yeung

Chemistry Publications

The use of MALDI MS as a fast and direct method to detect the Aβ oligomers of different masses is examined in this paper. Experimental results suggest that Aβ oligomers are ionized and detected as singly charged ions, and thus, the resulting mass spectrum directly reports the oligomer size distribution. Validation experiments were performed to verify the MS data against artifacts. Mass spectra collected from modified Aβ peptides with different propensities for aggregation were compared. Generally, the relative intensities of multimers were higher from samples where oligomerization was expected to be more favorable, and vice versa. MALDI MS was also …

Determination Of Phytosterols In Dried Shaggy Mane And Morel Mushrooms By Gc-Ms, Natalie Walker, Thomas W. Nalli

Undergraduate Research Celebration 2018

No abstract provided.

Metacognition And The Utility Of Pathway Maps In Introductory Chemistry, Kayla Schwartz

Honors Projects

Students historically struggle in introductory chemistry courses. This experiment was designed to test a hypothesized method to increase student success which utilized metacognition, reflection, and the creation of pathway maps. An introductory chemistry course at BGSU was given two sets of pre-assignments, pathway map assignments, and post-assignments which was related to the topics they were learning in class. The pre-assignments and post-assignments were used to determine if there was a change in understanding before and after the pathway map assignment was completed and the pathway map assignment was based on a question that was given in the pre-assignment. The students …

Advancing Professional Development Strategies For Chemistry And Biochemistry Undergraduates, Christian A. Brown

Senior Theses

In the Department of Chemistry and Biochemistry at the University of South Carolina (the Department), most curriculum-driven professional development is reserved for third- and fourth-year students. Classroom learning occurs at all levels, but the context comes late. Early exposure to career options and hands-on training is imperative for undergraduates to obtain maximum experiential learning. The purpose of this project is to advance the current professional development strategies of the Department, specifically targeting second- and third-year students. The study surveyed students' current involvement in professional development activities. The data on extracurricular experience and post-graduation interest was used to design a workshop …

Organocatalyzed Synthesis Of Epoxides From Chalcones Utilizing Amino Acids, Sabrina N. Kegeler

Masters Theses

The epoxide functional group is important throughout the chemical and pharmaceutical industries, as well as in nature. In the chemical industry, epoxides are present in resins and fragrances. In the pharmaceutical industry, epoxide-containing compounds are used as intermediates in the manufacturing of drugs. In nature, many natural products contain epoxide groups and are used for medicinal purposes, and for models to create synthetic molecules.

One approach to epoxide synthesis involves the use of an alkene precursor, a base, and an oxidizing agent. This is where my investigations began. The first step was to optimize the epoxidation reaction, examining substrate scope, …

Factors Affecting The Number And Type Of Student Research Products For Chemistry And Physics Students At Primarily Undergraduate Institutions: A Case Study., Birgit Mellis, Patricia Soto, Chrystal D. Bruce, Graciela Lacueva, Anne Wilson, Rasitha Jayasekare

2018 Faculty Bibliography

For undergraduate students, involvement in authentic research represents scholarship that is consistent with disciplinary quality standards and provides an integrative learning experience. In conjunction with performing research, the communication of the results via presentations or publications is a measure of the level of scientific engagement. The empirical study presented here uses generalized linear mixed models with hierarchical bootstrapping to examine the factors that impact the means of dissemination of undergraduate research results. Focusing on the research experiences in physics and chemistry of undergraduates at four Primarily Undergraduate Institutions (PUIs) from 2004–2013, statistical analysis indicates that the gender of the student …

Temperature And Electric Field Dependency Of Asymmetric Stretching Of Nitrate And Carbonate Ions, Konnor Jones

Masters Theses & Specialist Projects

Photolysis of nitrate ion in the natural environment produces NO, NO2, and O3, releasing these toxic gases into the atmosphere. Work done by other groups has shown ionic strength dependence of the ratio of products from photolysis of aqueous nitrate ion. To better understand the kinetic mechanisms of nitrate photolysis, the effects that ionic strength in solution have on nitrate ion symmetry breaking are needed. Different solvation environments induce nitrate bonding motifs that may be correlated to the product ratio. Fourier-transform infrared spectra of aqueous nitrate–ion solutions were obtained over a range of temperatures for several total electrolyte concentrations. The …

Principles Of Chemistry I & Ii (Ghc), Sarah Tesar, Allen Easton, Erin Kingston, Joseph Collins, Charles Garrison, Greg Ford, Christin Collins

Chemistry Grants Collections

This Grants Collection for Principles of Chemistry I & II was created under a Round Eight ALG Textbook Transformation Grant.

Affordable Learning Georgia Grants Collections are intended to provide faculty with the frameworks to quickly implement or revise the same materials as a Textbook Transformation Grants team, along with the aims and lessons learned from project teams during the implementation process.

Documents are in .pdf format, with a separate .docx (Word) version available for download. Each collection contains the following materials:

• Linked Syllabus
• Initial Proposal
• Final Report

Principles Of Chemistry I & Ii (Ccga), Colleen Knight, Leon Gardner, Joseph Lodmell, Ernest Pascoe, Andrea Wallace, Lisa Mcneal

Chemistry Grants Collections

This Grants Collection for Principles of Chemistry I & II was created under a Round Seven ALG Textbook Transformation Grant.

Affordable Learning Georgia Grants Collections are intended to provide faculty with the frameworks to quickly implement or revise the same materials as a Textbook Transformation Grants team, along with the aims and lessons learned from project teams during the implementation process.

Documents are in .pdf format, with a separate .docx (Word) version available for download. Each collection contains the following materials:

• Linked Syllabus
• Initial Proposal
• Final Report

Organic Chemistry I & Ii (Ccga), Colleen Knight, Leon Gardner, Joseph Lodmell, Ernest Pascoe, Andrea Wallace, Lisa Mcneal

Chemistry Grants Collections

This Grants Collection for Organic Chemistry I & II was created under a Round Seven ALG Textbook Transformation Grant.

Affordable Learning Georgia Grants Collections are intended to provide faculty with the frameworks to quickly implement or revise the same materials as a Textbook Transformation Grants team, along with the aims and lessons learned from project teams during the implementation process.

Documents are in .pdf format, with a separate .docx (Word) version available for download. Each collection contains the following materials:

• Linked Syllabus
• Initial Proposal
• Final Report

Spectroscopic And Crystallographic Characterization Of Enantiopure Planar Chiral N-Oxazolidinoyl Diene Iron (O) Tricarbonyl Complexes For Use In Diastereoselective Synthesis, Nathan W. Dow , '18

Senior Theses, Projects, and Awards

Iron(D) tricarbonyl-diene complexes have emerged from the field of organometallics as motifs of particular importance due to their robust synthetic applications. As a result of their planar chiral configurations, these removable iron units have been effectively used as diene protecting groups, stereodirecting groups and dienyl cation stabilizers to facilitate the total synthesis of architecturally complex structures, such as pharmaceutically-relevant natural products. However, to further optimize ironeD) tricarbonyl utilization in diastereoselective synthesis, methods must be developed to direct iron-diene complexation reactions in a facially selective manner and to characterize these optical outcomes. Additionally, the established number of reactions tolerant to ironeD) …

Elucidation Of The Toxicity Of Anthropogenic Nanoparticles In Environments Containing Heavy Metals, Chartanay Bonner

Dissertations

The design, synthesis, and applications of anthropogenic nanoparticles continue to rise as technologies utilizing the unique chemical and physical properties of materials with nanoscale dimensions emerge. Engineered silver nanoparticles (Ag NPs) possess antimicrobial properties toward several strains of antibiotic-resistant bacteria. The manufacturing and use of Ag NPs have led to their increased presence in the environment as pollutants. The interaction of Ag NPs with other pollutants influence their surface properties, aggregation state, stability and consequently, their toxic response toward microbial pathogens. In the present study, we examined the interaction of heavy metal ions (Cd²⁺, Hg²⁺, and …

The Impact Of The 515nm Effect On 1o2 Quenching In Photosynthesis: Model System Studies Using Β-Carotene–Acid Complexes, Lauren A. Hoody

Honors Theses

β-carotene (βC) is an orange pigment present in the photosynthetic reaction center (PRC) of green plants, where it plays a vital role in photosynthesis: It quenches singlet oxygen (1O2 , a toxic oxidizing species generated during photosynthesis) before the 1O2 damages chlorophyll and other components of the PRCs. During photosynthesis, βC temporarily converts from its native orange–450 state to a pink–515 state via the so–called 515nm Effect. Because of the differences between the electronic structures of orange–450 and pink–515, I hypothesize that pink–515 will quench 1O2 less efficiently than orange–450. This hypothesis has not been tested to date because orange–450 …

Versatile Sarcosine Biosensing Schemes Utilizing Layer-By-Layer Construction Of Carbon Nanotube-Chitosan Composite Films, Michael J. Pannell, Elizabeth E. Doll, Najwa Labban, Mulugeta B. Wayu, Julie A. Pollack, Michael C. Leopold

Chemistry Faculty Publications

Layer-by-layer composite films of carbon nanotubes (CNTs) within a chitosan matrix with sarcosine oxidase enzyme and capped with Nafion have been developed and optimized as a versatile 1st generation amperometric sarcosine biosensing platform that operates successfully both as an isolated sarcosine sensor as well as a functional component within a creatinine sensor. Accurate measurement of sarcosine in urine and creatinine in blood may help with early diagnosis of diseases such as prostate cancer and renal failure, respectively. In this study, each material within the film is systematically optimized toward sarcosine sensitivity, including a critical evaluation of different CNTs effect on …

Investigations Of The Putative Ai-2 Receptor Protein Lsrb From Thermobacillus Composti And Truncations Of The Salmonella Enterica Ser. Typhimurium Lsre Protein, Nicholas E. Petty , '18

Senior Theses, Projects, and Awards

Bacteria were believed to exist as solitary, unicellular organisms until about 50 years ago with the discovery of quorum sensing by John Woodland Hastings. Since then, numerous studies have examined the broad reaching functions controlled by bacterial quorum sensing, including biofilm formation and virulence. Work done by the Bassler laboratory proposed a "universal" quorum sensing pathway that uses a novel signal molecule, autoinducer-2 (AI-2), for intraspecies and interspecies communication. This quorum sensing pathway uses proteins encoded by the lsr operon to uptake and process the AI-2 signaling molecule. This work examines two of these proteins, LsrE and LsrB. LsrE, a …

Biogeochemical Cycling Of Selenium In The Arctic Ocean, Kyle M. Mcquiggan

OES Theses and Dissertations

Changes in the global climate may have a pronounced effect on the biogeochemical cycling of trace elements like selenium (Se) in the Arctic Ocean. This study described the first quantitative examination of the biogeochemical cycle of selenium in the Amerasian Basin, providing the baseline from which future changes can be identified. Aerosol, dissolved and particulate water samples were collected for Se determinations during the U.S. GEOTRACES GN01 Arctic expedition that sampled the two parts of the Amerasian Basin in 2015: The Makarov Basin on the way to the North Pole and the Canada Basin on the return trip to Dutch …

Pitch Measurements In A Chiral Lyotropic Chromonic Liquid Crystal: Temperature And Dopant Concentration Dependence Of The Pitch, Timothy Ogolla , '18

Senior Theses, Projects, and Awards

The antihistamine, disodium cromoglycate (DSCG), forms a nematic (N) phase in which the molecules are stacked like a pile of cards to form columnar assemblies; addition of a small amount of chiral molecules can form a chiral nematic (N*) phase, with the assemblies arranged around a helical axis. For thermotropic liquid crystals (TLCs) the pitch is usually measured using the Cano wedge method, and in lyotropic chromonic liquid crystals (LCLCs) the fingerprint texture is typically used. The effect of a dopant on the pitch of a chiral LCLC is quantified using the helical twisting power, which is the slope of …

Nadph-Cytochrome P450 Oxidoreductase: Extraction Of The Full-Length Protein And Methyl-Trosy Nmr Of The Soluble Mutants, Sara Ali Jamal Arafeh

Master's Theses (2009 -)

NADPH-cytochrome p450 oxidoreductase (CYPOR) is a membrane-bound protein in living cells. CYPOR delivers electrons to cytochrome p450 proteins (CYPs) to catalyze metabolism of drugs and synthesis of steroids. Extraction and solubilization of CYPOR from the membrane is typically done with the TritonX-100 detergent. The amount of the solubilized protein by this detergent, however, remains relatively low to structurally analyze CYPOR with NMR spectroscopy. The goal of the first project in this thesis was to optimize the amount of the extracted CYPOR from the E. coli membrane using various detergents and additives. To this aim, non-ionic detergents with variable hydrophobicity (TritonX-100, …

Photoremovable Protecting Groups Based On Electrocyclization With Leaving Group Expulsion Via A Proposed Zwitterion, Gilbert Ndzeidze

Dissertations (1934 -)

The triplet excited state of thioxanthone produced by photolysis undergoes reversible triplet energy transfer with a trimethylene - linked benzothiophene-2-carboxanilide ring system. The ensuing electrocyclic ring closure of the anilide moiety produces a putative zwitterionic intermediate that is capable of expelling leaving groups (LG-) from the C-3 position of the benzothiophene ring. Stern-Volmer quenching studies with cyclohexadiene as quencher furnish the rate constants for the triplet excitation transfer in the forward and reverse directions, which can be expressed as an equilibrium constant K = 0.058. Overall, the rate of triplet excited state reaction becomes K x kr = 5.7 x …

Synthesis And Characterization Of Biomimetic Models Of Mononuclear Nonheme Iron Dioxygenases And Their Reactive Intermediates, Anne Alyse Fischer

Dissertations (1934 -)

Mononuclear non-heme iron dioxygenases (MNIDs) are a class of enzymes that catalyze a variety of reactions, from amino acid catabolism to bioremediation using molecular oxygen. This work focuses on three types of MNIDs: thiol dioxygenaes (TDOs), aminophenoldioxygenases (APDOs), and sulfoxide synthases (SOSs). TDOs, found in mammals, regulate the levels of cysteine along with other thiol-containing molecules, using molecular oxygen to convert them into their corresponding sulfinic acids. APDOs catalyze the oxidative ring cleavage in the biodegradation of nitroaromatics. SOSs are involved in the biosynthesis of large biologically relevant molecules in humans. Although this class of enzymes has gained more attention …