Biochemistry Commons^™

Retro-Structural Analysis Of The Four Helix Bundle Motif In Binuclear Proteins, Walker Pedigo, Maggie Smith

Honors Theses

Protein structure is directly related to protein function. There are four levels of protein structure: primary, secondary, tertiary, and quaternary. The interactions amongst the structural components of a protein give rise to its unique characteristics. The four helix bundle motif is a common structural trait in a variety of binuclear proteins. In this study, PyMOL, a molecular visualization system, was used to analyze binuclear proteins that possess a four helix bundle. Images of proteins containing dicopper, diiron, and dimanganese sites were captured. The images were compiled into figures for each individual protein. After creating the figures, each protein was further …

G Protein–Coupled Receptor 21 In Macrophages: An In Vitro Study, Valentina Bordano, Gemma K. Kinsella, Stefania Cannito, Chiara Dianzani, Casimiro Luca Gigliotti, John C. Stephens, Chiara Monge, Claudia Bocca, Arianna C. Rosa, Gianluca Miglio, Umberto Dianzani, John B.C. Findlay, Elisa Benetti

Articles

GPR21 is an orphan and constitutively active receptor belonging to the superfamily of G-Protein Coupled Receptors (GPCRs). GPR21 couples to the Gq family of G proteins and is markedly expressed in macrophages. Studies of GPR21 knock-out mice indicated that GPR21 may be involved in promoting macrophage migration. The aim of this study was to evaluate the role of GPR21 in human macrophages, analyzing (i) its involvement in cell migration and cytokine release and (ii) the consequence of its pharmacological inhibition by using the inverse agonist GRA2. THP-1 cells were activated and differentiated into either M1 or …

Determining The Distribution Of Elemental Compounds And Oxidative Potential Across Fine Particulate Matter (Pm2.5) Filters, Allie Michelle Sidwell

Honors Theses

Fine particulate matter (PM_2.5) is a complex mixture of particles and sorbed chemicals that poses serious, adverse effects on human health such as increasing cardiovascular and respiratory morbidity and mortality. There is ongoing research into the impacts of PM_2.5 of differing chemical compositions, sampling location, and the mechanisms for the observed health effects. To conduct these analytical and toxicology studies of PM_2.5, researchers often split filters into sections. This process allows multiple, often destructive, assays to be performed. Our previous research showed chemical composition differences across PM_2.5 filters. The goal of our study was …

Innate Immunity In The Pathobiology And Treatment Of Infectious And Neurodegenerative Diseases, Mai Mostafa

Theses & Dissertations

Mononuclear phagocytes (MPs; monocytes, macrophages, and dendritic cells) are the governors of innate immunity which is the body’s first line of defense against microbial pathogens. They act beneficial or detrimental. They are crucial for an effective non-specific immune response to invading pathogens by engulfing, destroying, then eliciting an adaptive specific immune response. Given their pivotal functions in the host immune defense, studying MP immune responses in disease is paramount important for understanding disease pathobiology and uncovering therapeutic strategies.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the driver of acute respiratory distress syndrome (ARDS) in coronavirus disease 2019 (COVID-19) amongst …

Mechanisms Of Sorting And Fission At The Endosomes, Kanika Dhawan

Theses & Dissertations

Endocytic trafficking is a fundamental cellular process that regulates the transport of lipids and proteins. Our lab focuses on the intracellular trafficking of receptors involved in cellular processes such as cell division, migration, and proliferation. Accordingly, the regulation of these trafficking pathways is tightly controlled, involving a complex series of events, of which a key step is the endosomal fission. Perturbations in the endosomal network can eventually lead to impaired receptor recycling to the plasma membrane (PM) and, therefore, have pathological consequences like Alzheimer’s disease and multiple cancers. Upon internalization, cargo-laden vesicles released from the PM fuse with the sorting …

Paf1/Pd2 Augments Pancreatic Cancer Progression And Mediates Radiation And Chemoresistance, Sanchita Rauth

Theses & Dissertations

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Novel Molecular Mechanisms Of C-Terminal Eps15 Homology Domain (Ehd) Proteins In Endocytic Trafficking And Primary Ciliogenesis, Tyler M. Jones

Theses & Dissertations

Endocytic membrane trafficking is a key cellular process that is critical for regulating the transport of internalized cargoes such as lipids and receptors. Our lab focuses on understanding the mechanisms and cellular functions of the proteins that regulate this pathway. One family of proteins that has seen significant interest over recent years is the C-terminal Eps15 Homology Domain (EHD) family of proteins. Mammalians have four EHD paralogs (EHD1-4) that are expressed ubiquitously in tissues. These proteins have distinct yet overlapping functions in regulating endocytic pathways. EHD1 has been shown to induce constriction and is recruited to induce fission of tubular …

Analysis Of The Light Responsive Azobenzene Peptide Nucleic Acid Duplexes, Kat Nguyen

Honors College Theses

Peptide nucleic acids (PNAs) are oligonucleotide analogues in which the sugar-phosphate backbone has been replaced by a pseudopeptide skeleton. Since PNAs use the natural nucleobases (Adenine, Thymine, Cytosine, Uracil, and Guanine) found in either DNA and/or RNA, they are able to hybridize according to Watson-Crick base-pairing to form duplexes. PNA is a promising therapeutic agent because they can function as antigene or antisense chemical agents. To further enhance their utility, we aim to incorporate a photoswitchable moiety using azobenzene. Here, we report the results of the synthesis and purification of a photoswitchable 11 mer PNA along with initial characterization efforts.

The Use Of Nebulizer Medications As A Possible Treatment For Covid-19, Jacob Kaufman

Honors College Theses

For the past few years, the COVID-19 pandemic has been the focal point in healthcare and research. This disease has permanently changed daily life and left a historic impact on the world. Most people have felt the effects of this pandemic either directly, via infection, or indirectly, via change in workflow, financial impact, etc. The main question for this virus still remains today; how do we treat this illness effectively? While many ideas are being tested and suggested, a definite answer has yet to be procured. Vaccine rates are climbing on a daily basis, serving as the first and most …

Finding The Optimal Ionic Liquid To Target White Blood Cell Subpopulations Using Nanoparticles, Meghan Gorniak

Honors Theses

Disorders and diseases of the immune system have become more prevalent in recent decades and can have life-threatening effects on those afflicted. Granulocyte disorders disproportionately affect infants and children, while chronic lymphocytic leukemia is the most common type of leukemia in adults. Unfortunately, current treatments have many drawbacks such as everyday injection, short-lived efficacy, and unknown levels of safety and effectiveness. It is imperative to find more effective treatment options that could allow for easier drug delivery to specific populations of white blood cells (WBCs). Nanoscale medicine shows promising application, but complications remain in reaching the desired target site and …

Mechanisms Of Telomere Maintenance In Trypanosoma Brucei, M A G G. Rabbani

ETD Archive

Telomeres are a nucleoprotein structure at the end of the chromosome and are essential for genome integrity and chromosome stability. Telomere lengths are primarily maintained by a telomerase-mediated pathway but can be maintained by a homologous recombination-mediated pathway. However, detailed mechanisms of telomere maintenance are still unclear in many eukaryotes, including an important human pathogen, Trypanosoma brucei. Telomeres can be elongated by telomerase in T. brucei, a causative agent of fatal sleeping sickness in humans and nagana in cattle. T. brucei evades host immune response by regularly switching its major surface antigen, variant surface glycoprotein (VSG), a process known as …

The Effects Of Crowding Agents On The Pka Of Physiologically Stable I-Motif Dna, Courtney Turner

Honors Theses

The overall goal of this thesis was to investigate the environmental conditions that induce i-Motif folding of the DNA strand DUX4L22, a cytosine-rich segment of DNA found in the human genome. Cellular conditions were simulated using sodium cacodylate buffer and multiple weights of polyethylene glycol as a crowding agent. The presence of i-motifs were confirmed by Circular Dichroism spectroscopy. I found that DUX4L22 does form i-motifs under these physiological simulations at both acidic and neutral pHs. DUX4L22 therefore shows potential for use in studies of a wide variety of biotechnological advances, such as regulatory switches in nanomachines or drug-delivery systems.

Unusual High-Frequency Mechanical Properties Of Polymer-Grafted Nanoparticle Melts, Mayank Jhalaria, Yu Chang, Yucheng Huang, Brian C. Benicewicz, Sanat K. Kumar, George Fytas

Faculty Publications

Brillouin light spectroscopy is used to measure the elastic moduli of spherical polymer-grafted nanoparticle (GNP) melts as a function of chain length at fixed grafting density (0.47  chains/nm²) and nanoparticle radius (8 nm). While the moduli follow a rule of mixtures (Wood’s law) for long chains, they display enhanced elasticity and anomalous dissipation for graft chains <1⁢0⁢0  kDa. GNP melts with long polymers at high 𝜎 have a dry zone near the GNP core, surrounded by a region where the grafts can interpenetrate with chain fragments from adjacent GNPs. We propose that the departures from Wood’s law for short chains are due to the effectively larger silica volume fraction in the region where sound propagates—this is caused by the short, interpenetrated chain fragments being pushed out of the way. We thus conclude that transport mechanisms (of gas, ions, sound, thermal phonons) in GNP melts are radically different if interpenetrated chain segments can be “pushed out of the way” or not. This provides a facile new means for manipulating the properties of these materials.

Covalent Modification Of Recombinant Protein With Reactive Thiols, Sawyer Dulaney, Bailey Taylor

Honors Theses

Many diseases cause chronic and painful inflammation in different body systems. One of the front-line drug classes to treat such inflammation is Nonsteroidal Anti-Inflammatory Drugs (NSAIDs). Despite the benefits of oral administration of NSAIDs, there are drawbacks to their long-term usage because they can cause detrimental effects on off-target systems in the body such as the liver, kidney, or the lining of the intestinal tract. An alternative to NSAIDs is the usage of hydrogels for targeted drug delivery. Hydrogels can provide drug delivery in a specific portion of the site of inflammation, thus allowing higher doses of medication to be …

Vitamin D And Its In Vitro Therapeutic Action Mediated Through Vdr Rather Than Pdia3, Jaeden Pyburn

Undergraduate Honors Theses

Brain calcification is a common occurrence in the aging process, with >20% of individuals over the age of 65 showing hardened plaques in the basal ganglia. Loss of the vitamin D receptor (VDR) in transgenic mice leads to formation of calcified plaques in the basal ganglia and thalamus within the mice. Vitamin D signals through two known vitamin D responsive proteins, protein disulfide isomerase A3 (PDIA3) and VDR. In vitro, vitamin D has been demonstrated to suppress calcification in osteoblast-like cells. Here, we aim to elucidate which of either PDIA3 or VDR transduce vitamin D mediated suppression of calcification in …

Severe Hypoxia Up-Regulates Gluconeogenesis In Daphnia, Morad C. Malek

Undergraduate Honors Theses

Hypoxia is a significant low oxygen state that has complex and diverse impacts on organisms. In aerobes, various adaptive responses to hypoxia are observed that vary depending on the level of oxygen depletion and previous adaptation, hence the continued attention to hypoxia as an important abiotic stressor. Adaptive responses to hypoxia are primarily governed by the hypoxia-inducible factors (HIFs), which activate downstream genetic pathways responsible for oxygen transport and metabolic plasticity. In aquatic habitats, oxygen availability can vary greatly over time and space. Therefore, aquatic organisms’ adaptation to hypoxia is likely pervasive, especially in genotypes originating from waterbodies prone to …

Targeting Neuronal Nitric Oxide Synthase (Nnos) For Melanoma Treatment, Shirley Tong

Pharmaceutical Sciences (PhD) Dissertations

Human cutaneous melanoma is the most aggressive form of skin cancer and the incidence rates have continued to increase over the years. Neuronal nitric oxide synthase (nNOS) produces nitric oxide (NO) has been found to be overexpressed in human melanoma and the expression of nNOS is induced by interferon-gamma (IFN-γ). In our studies, nNOS has been implicated in IFN-γ-stimulated melanoma progression and the inhibition of nNOS using novel inhibitors effectively inhibited IFN-γ-stimulated tumor growth in a xenograft mouse model. Programmed death-ligand 1 (PD-L1) is overexpressed in melanoma and plays an important role in suppressing the immune system ^12-14. Our …

Synthesis, Structural Characterization, And In Vitro Biological Assessment Of Trans- Platinum (Ii) Thionate Complexes As Potent Anticancer Agents, Mia Alshami

Chemistry & Biochemistry Undergraduate Honors Theses

The content of this thesis has been originally reported in our published paper, “trans-Platinum (II) Thionate Complexes: Synthesis, Structural Characterization, and in vitro Biological Assessment as Potent Anticancer Agents” ChemPlusChem 2019 84, 1525-1535, DOI: 10.1002/cplu.201900394, in which I served as coauthor. Cancer caused 9.6 million deaths in 2018 worldwide, with 18.1 million new diagnoses during that same year.The most widely used metal in anticancer drugs is platinum (Pt), and these drugs are used to treat almost 50% of cancer patients. To optimize drug effectiveness, trans-configured Pt(II) complexes have been introduced as a strategy to potentially overcome the …

Studying The Lysine Acetylation Of Aconitase Isozymes In E. Coli, Sara Ottinger

Chemistry & Biochemistry Undergraduate Honors Theses

The contents of this thesis have been modified from the publication “Araujo J, Ottinger S, Venkat S, Gan Q and Fan C (2022) Studying Acetylation of Aconitase Isozymes by Genetic Code Expansion. Front. Chem. 10:862483”. Though studies have found multiple lysine sites in which acetylation takes place in Escherichia Coli aconitase, acetylation’s effects on the enzyme’s activity have yet to be studied. Aconitase is the dehydratase-hydratase found in the citric acid and glyoxylate cycles responsible for the reversible isomerization of citrate to isocitrate via cis-aconitate intermediate. There are two isoforms of aconitase in E. coli: AcnA and AcnB. In …

Hyper Stable Variants Of Fgf-1-Fgf-2 Dimer, Madison Shields Mcclanahan

Chemistry & Biochemistry Undergraduate Honors Theses

Fibroblast Growth Factors (FGFs), including FGF-1 and FGF-2, are proteins that play a crucial role in cell proliferation, cell differentiation, cell migration, and tissue repair. FGF-1 and FGF-2 are useful in accelerating the healing process in the human body; however, these proteins are naturally thermally unstable, resulting in a relatively low half-life in vivo. 1,8 In efforts to improve the stability of this protein, FGF-1 and FGF-2 proteins are engineered by combining the amino acid sequences of the two proteins to form a heterodimer and obtain novel properties. These two FGF variants are chosen for their specific wound healing capabilities. …

Characterization Of A Potential Glucose Transporter In Trypanosoma Brucei, Matthew Morgan

All Theses

Trypanosoma brucei, the African trypanosome, is an organism heavily dependent on glucose for ATP production during the infectious stage of its life cycle. Here, we have explored the role of an uncharacterized protein designated “novel glucose transporter” (NGT) as a potential glucose transporter. Sequence analyses suggests that NGT shares similarities (either at the primary sequence level or structurally) with Trypanosome Hexose Transporters 1 (TbTHT1), and human GLUT3, both of which are membrane sugar transporters. NGT was localized by fluorescence microscopy to subcellular structures consistent with lysosomes. Silencing NGT expression with RNA interference in parasites resulted in a growth defect …

Characterization Of A Protein-Small Molecule Interaction Between Microtubules And Novel Ruthenium-Polypyridyl Complexes, Chloe Hutchison

Chemistry & Biochemistry Undergraduate Honors Theses

Microtubules are cytoskeletal filaments that play a role in essential functions within the cell such as cell motility, intracellular transport, structural support and chromosome segregation. Tubulin is a heterodimeric protein that exhibits GTP dependent polymerization and self- assembles into polar microtubule filaments. Microtubules are dynamic polymers corresponding to their role in separation of duplicated chromosomes during mitosis. As the polymers cycle through rounds of polymerization and depolymerization based on their nucleotide state, the chromosomes are pulled towards the poles in the mitotic cell. Their normal function and dynamics can be disrupted in highly proliferative cells that interrupt cell cycle progression …

An Investigation Into The Roles Of Aldose Reductase And Acetate Kinase In The Metabolism Of Entamoeba Histolytica, Matthew B. Angel

All Dissertations

Entamoeba histolytica is an amoebic parasite that infects an estimated 90 million people worldwide and causes approximately 100,000 deaths per year. As the causative agent of amoebic dysentery, this food- and water-borne pathogen represents a significant public health burden worldwide, particularly in areas with poor sanitation. While treatments for amoebiasis exist, they are often limited in their effectiveness. Thus, efforts to better understand the biology and physiology of this organism are vital to the development of novel treatments for this disease.

E. histolytica lacks the enzymes for many common metabolic pathways such as the citric acid cycle and oxidative phosphorylation …

Studying Acetylation Of Aconitase Isozymes By Genetic Code Expansion, Jessica Araujo

Graduate Theses and Dissertations

The tricarboxylic acid (TCA) cycle is a very important, centrally located, energy-producing pathway that connects numerous other metabolic and regulatory pathways. Enzymes of this cycle have been more recently implicated in various cancers and neurometabolic disorders, however, the exact mechanism by which this happens becomes quite complex when considering the potential modification of these enzymes and the presence of multiple forms of the enzymes and therefore there is much to be studied in this area.

Aconitase has become a recent enzyme of interest as its substrate, citrate, has been found to play a major role in many vital processes within …

Characterization Of The Role Of The Replicase And Quasispecies Diversity In Flaviviral Evolution And Host Adaptation, Haley Caldwell

Legacy Theses & Dissertations (2009 - 2024)

Flaviviruses include several emerging and re-emerging arboviruses that cause millions of infections each year. Although relatively well-studied, much remains unknown regarding the mechanisms and means by which these viruses adapt to different hosts and rapidly alternate between hosts. Different aspects of flaviviral biology impact host switching, viral fitness, and the generation of viral diversity during genome replication by the NS3 and NS5 proteins. Together these factors may impact host plasticity.

Nanotechnology-Based Approaches To Mitigate Environmental Pollutants -- Induced Neurological Disorders, Jyoti Ahlawat

Open Access Theses & Dissertations

Neurodegenerative diseases such as Parkinson's disease (PD), Alzheimerâ??s Disease (AD) and Huntingtonâ??s Disease (HD) have no cure despite intensive research efforts geared towards therapeutics development. In the USA, patients with PD and AD alone cost the nation ~ $200 billion annually in patient care and lost productivity. Therefore, there remains an urgent and unmet need to develop novel drugs and drug carriers with the potential to slow down, halt and ideally reverse the course of neurodegenerative disorders. The dissertation focuses on developing approaches towards targeting PD using multifactorial mechanisms including the targeting of protein aggregation and oxidative stress. This is …

Investigation Of The Binding Domain Interfaces Of The C-Terminus Of The Albino3 Insertase And The 43kda Chloroplast Signal Recognition Particle Subunit Via Single Molecule Förster Resonance Energy Transfer, Amanda Tomanek

Chemistry & Biochemistry Undergraduate Honors Theses

Fluorescent labeling is a technique used for visualizing functional groups contained in biomolecules by fluorescence imaging. This technique was used in this project to analyze post-translational targeting of light-harvesting chlorophyll-binding proteins (LHCP), which are the core complexes that harvest sunlight to drive photosynthetic electron transfer. This protein is synthesized in the cytosol and post-translationally targeted to the stroma of chloroplasts. CpSRP43 is a signal recognition particle (SRP) subunit unique to chloroplasts, which has been shown to interact with the stroma-soluble C-terminus of the thylakoid-bound Albino3 insertase (Alb3-Cterm). In the chloroplast stroma, targeting to thylakoids is performed via the cpSRP pathway …

Characterization Of Fgf1/Fgf2 Heterodimer With Mutation R136e, Brett Haley

Biological Sciences Undergraduate Honors Theses

Fibroblast growth factors are a family of heparin binding proteins that are involved in a broad spectrum of physiological functions, such as angiogenesis, cell proliferation, cell differentiation, and wound healing. Fibroblast growth factor 1 (FGF-1) is a member of the FGF superfamily and can bind universally to fibroblast growth factor receptors. Fibroblast growth factor 2 (FGF-2) is similar in structure to FGF-1 but has been shown to have a potent effect on angiogenesis. A physiologically stable dimerization of these two growth factors could prove to induce desirable effects in the instance of wound healing. In this study, we have designed …

Regulation Of The Reaction Between Cytochrome C And Cytochrome C Oxidase In The Mitochondria, Anders Nowell

Biological Sciences Undergraduate Honors Theses

Cytochrome c (Cc) is a multifunction protein that has important life and death functions in the cell. In the electron transport chain (ETC), Cc transfers electrons from cytochrome bc₁ to cytochrome c oxidase (CcO), which helps build the electrochemical gradient that drives ATP synthase. The reaction of Cc with CcO is very important in ETC regulatory processes. Previous research shows phosphorylation sites in Cc that affect the binding with CcO, with measurable effects on k_d, k_f, and K_D. These effects result in changes in mitochondrial membrane potentials, respiration, and reactive oxygen species (ROS) …

Role Of E168d In M. Tuberculosis Igps Catalysis, Hedda Booter

Theses, Dissertations and Culminating Projects

Mycobacterium tuberculosis is a bacterium that affects the lungs and causes tuberculosis, infecting over 10 million people worldwide each year. Owing to the organism’s evolving drug resistance, existing antibiotics no longer combat the disease. The need to discover new drug targets has never been greater. Previous findings suggest that the protein IGPS (indole-3-glycerol phosphate synthase) in M. tuberculosis (MtIGPS) may be a target in the treatment of the disease. MtIGPS catalyzes the fourth step in the tryptophan biosynthetic process. The ability to create their own tryptophan is a major advantage that many bacteria have. The role of E168, in the …