Biochemistry, Biophysics, and Structural Biology Commons^™

The Role Of Ccaat Binding Factor In The Regulation Of Catalase Gene Expression In Candida Albicans, Zahra Al-Rumaih

Graduate Theses and Dissertations

Candida albicans is a fungal opportunistic human pathogen. Its infections range from surficial infections like skin rash to fatal systemic infections. Filamentation growth mode is associated with C. albicans virulence because it helps penetration of the host’s epithelial cells. The CCAAT-binding factor (CBF) is a conserved heterooligomeric transcription factor found in 30% of eukaryotes genes. In C. albicans it is composed of 4 major subunits, including Hap2, Hap3, Hap4, and Hap5. Hap2 and Hap5 are essential for DNA binding and function. Hap4 has 3 homologous subunits: Hap41 and Hap42 are putative subunits of CBP. Hap43 is the only Hap4 subunit …

Time Course Investigation Of The Dermal Leukocyte Response To Lipoteichoic Acid In Chickens, Ian Gilbert

Animal Science Undergraduate Honors Theses

Lipoteichoic acid (LTA) is component of the cell wall of Gram-positive bacteria that stimulates inflammation during bacterial infection. However, few studies have investigated the in vivo immune response to LTA, and none of the in vivo studies done have been performed in birds. For this project, the pulp (a skin-derivative) of growing feathers (GFs) of chickens were used as a test site to investigate the in vivo effects of intradermally injected LTA. In Study 1, the pulp of 12 GFs of 11-week-old Light-brown Leghorn (LBL) males were injected with 10 μL of differing concentrations of LTA (0.1, 1.0, 10, 100 …

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 …

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 …

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 …

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 …

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. …

Macronutrient Availability Shapes Host Response To Infection And Feeding Behavior, Weston Gerald Perrine

Graduate Theses and Dissertations

Macronutrients in the diet are vital to the physiological processes necessary for an organism to effectively clear a pathogen. Diet can be important to a host’s susceptibility to infection and severity of pathology, though results can vary across host-pathogen systems (Sen et al. 2016). Manipulating the ratio of specific macronutrients in the diet is an effective method to begin understanding how individual macronutrients, rather than food types, have on immune responses. Using an avian host-pathogen system, I explored the effects of dietary macronutrient composition, specifically lipid and protein content, on disease pathology and behavior of canaries (Serinus canaria) infected with …

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 …

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 …

Preparation Of Proteins And Peptides From Heat-Stabilized Defatted Rice Bran Via Solid State Fermentation And Investigating For Skin Health, Ali A. Bisly

Graduate Theses and Dissertations

Heat-stabilized defatted rice bran (HDRB) is an abundant and inexpensive agro-industrial by-product of rice milling and rice oil extraction process. Furthermore, HDRB is a potential source of proteins. However, the direct protein extraction has low yield of protein due to the impact of heat stabilization and oil extraction process which made the HDRB proteins bound and interact with other components. This research is based on using solid-state fermentation (SSF), which is a natural and cost-effective approach to facilitate protein extraction from HDRB using Bacillus subtilis (natto) Takahashi as a microorganism.

Response surface methodology (RSM) analysis was used with Box-Behnken design …

Spike Protein Structural Dynamics Of Sars-Cov-2 Coronaviruses Studied Using Molecular Dynamics, William Strickland

Biological Sciences Undergraduate Honors Theses

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has overwhelmingly impacted the global population, accounting for millions of confirmed infections and deaths over the last year. The virus’s influence on the health and safety of individuals, the economy, and daily life has been disruptive and devastating. While SARS-CoV-2 and SARS-CoV-1, two closely related members of the SARS coronaviruses, have shown the ability to cross the species barrier and infect humans, SARS-CoV-2 has predominantly been the virus responsible for the number of infections presently known. SARS-CoV-2 has also proven to be volatile, as many variants have …

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) …

Ongoing Calculus In The Cerebral Cortex, Luke Long

Physics Undergraduate Honors Theses

Various modes of neuronal computations have long been theorized to be possible based on the structure and geometry of the brain. These computations also seem necessary for many of the integral functions of the brain, like information processing and regulatory processes in the body. However, experimental data directly supporting these claims have been rare.

In this study, data collected in mice from a large number of neurons over a long period of time provided the opportunity to search for some of these computations, specifically change detection and squaring calculations. Using Matlab, the goal of this analysis was to find statistically …

Physical Characteristics And Classification Of The Large Amplitude Variable Star V1719 Cygni, Ashley Lieber, Logan Siems, Julia Kennefick, Michael Fitzgerald

Inquiry: The University of Arkansas Undergraduate Research Journal

Pulsating stars are used as standard candles which are helpful in determining distances to stellar objects along with the relationship between their period and apparent luminosity. The focus of this study was the variable star, V1719 Cygni, which is often classified as a Delta (δ) Scuti star, but there exists debate that it should be classified as a RR Lyrae star due to its abnormal light curve and similar characteristics between the two variable star categories. Observational data was taken in 2019 using the Las Cumbres Observatory international telescope network. The resulting data were calibrated using comparison stars in the …

Deciphering Chemomechanical Couplings In Proteins Using Microsecond-Level Molecular Dynamics Simulations, Vivek Govind Kumar

Graduate Theses and Dissertations

All-atom molecular dynamics (MD) simulations combine the high temporal resolution of experimental methods like smFRET and spatial resolution of methods like x-ray crystallography, to provide a detailed dynamic picture of biomolecular processes. Here, microsecond-level atomistic MD simulations have been used to characterize chemomechanical couplings in human fibroblast growth factor 1 (hFGF1) and the spike proteins of SARS CoV-1 and SARS-CoV-2. hFGF1 is a globular signaling protein that is involved in several physiological processes ranging from cell proliferation to wound healing. Experimental studies have previously described the low proteolytic and thermal stability of hFGF1, in addition to the stabilizing role of …

Site-Specific Effects Of Lysine Acetylation On Aminoacyl-Trna Synthetase, Hao Chen

Graduate Theses and Dissertations

Aminoacyl-tRNA synthetases (AARSs) are an ancient and highly conserved family of enzymes which can catalyze a two-steps aminoacylation reaction to charge tRNAs with their cognate amino acids, thus playing crucial roles in ribosomal protein synthesis. Naturally, the accurate amino acids and tRNA recognition of these synthetases are essential to the fidelity of translation process. To assure the correct recognition, some of these synthetases have evolved with an editing function to help remove the mischarged tRNAs. In addition to these functions, AARSs are also involved in various biological processes ranging from transcription to translation. Currently, a series of proteomic studies have …

Effects Of Localized Oxygen Production By Electrolysis On The First-Generation Glucose Sensor Response, Nandita Halder

Graduate Theses and Dissertations

Glucose sensors are very important for detecting blood glucose both in vitro and in vivo. First-generation glucose biosensors were based on the glucose oxidase (GOx) enzyme using molecular oxygen as the electron acceptor and therefore oxygen dependent. Unfortunately for in-vivo work, oxygen in the body is variable and limited. Alternative approaches to overcome the oxygen dependency came with their own limitations. The widely used and commercially available ex-vivo glucose test strip uses a mediator in place of oxygen to free it from oxygen dependency. The mediator-based technology, in most cases cannot be transferred to in vivo applications due to the …

Engineering Fluorescently Labeled Human Fibroblast Growth Factor One Mutants And Characterizing Their Photophysics Properties Towards Designing Fret Assays, Mamello Mohale

Graduate Theses and Dissertations

Human fibroblast growth factor one (hFGF1) belongs to a family of 22 FGF members produced by fibroblast cells. Cell signaling during physiological processes of angiogenesis and wound healing occurs when hFGF1 binds to its receptor (FGFR). However, when heterogenous homeostasis is not maintained, fibroblast cells exhibit excessive proliferation which can lead to a myriad of cancers. smFRET is an ultrasensitive distant dependent (1-10 nm) technique capable of resolving such heterogeneity in structural dynamics and binding affinities (Kd). Therefore, we successfully designed and characterized fluorescently labeled hFGF1 tracers which span the visible light region of the electromagnetic spectrum for use in …

Enzymatic Degradation Of Microcystin-Lr By Microcystinase (Mlra), Faisal Alqhtani

Graduate Theses and Dissertations

Microcystin-LR (MC-LR) is affecting the water supply worldwide. Hence, a way to eliminate this toxin is an essential target. In this study, successful cloning of the mlrA gene and producing MlrA enzyme that can degrade the cyclic MC-LR to linearized MC-LR was done. MlrA protein was expressed in Escherichia coli BL-21 (E. coli). Also, enhancing the MlrA yield by adding nickel to LB media was a success in producing more MlrA enzyme from the same volume. Even though the enzyme showed no activity after adding Ni, the enzyme was expressed at a higher yield. Furthermore, it was to investigate adding …

Investigating Effects Of Microenvironmental Stress On Cell Metabolism Using Multiphoton Imaging, Lisa Rebello

Graduate Theses and Dissertations

Resistance to therapy in cancer is a major cause of poor prognosis in patients. Tumor hypoxia plays an active role in mediating treatment resistance and has been linked to metastases and metastatic potential in cancer. Our research focused on three objectives: i) To understand metabolic effects of chronic and intermittent hypoxia in murine breast cancer cells and its affiliation with metastatic potential ii) To identify the metabolic changes associated with radiation therapy in a panel of radiosensitive and radioresistant human head and neck cancer cells and iii) to monitor the changes in cell metabolism associated with gain of treatment resistance. …

Characterization Of Iron-Sulfur Cluster Biogenesis In Methanogenic Archaea, Thomas Modlin Deere

Graduate Theses and Dissertations

Iron-sulfur (Fe-S) clusters are among the oldest cofactors on the planet, used by proteins in almost all forms of life on Earth to carry out processes ranging from energy transfer to DNA replication. Among the organisms believed to use these Fe-S proteins more extensively than almost any others are the methanogens, an ancient lineage of archaeal microbes that produce methane as a required product of their metabolism. Methane, the primary component of commercial natural gas, is both a potent greenhouse gas and an important fossil fuel. It can also be renewably produced as a biofuel. Biogenic methane is almost entirely …

The Characterization Of Angiopoietin-Like Protein 4 Overexpression In Triple Negative Breast Cancer, Jodi Simeon

Graduate Theses and Dissertations

Triple Negative Breast Cancer (TNBC) is highly invasive and metastatic with approximately 15% of patients developing liver metastases. The primary treatment of metastatic TNBC is chemotherapy, however, there is an increased chance of resistance to this therapeutic technique. If Breast Cancer Liver Metastasis (BCLM) is left untreated most patients survive only 4 to 8 months with a very rare 5-year survival. Therefore, it is imperative to analyze markers and molecular pathways that TNBC cells use to progress, invade, and metastasize to the liver. The aim of this study was to examine the overexpression of angiopoietin-like 4 (ANGPTL4) in TNBC cells …

Evaluating Bioenergetics And Mitochondrial Dynamics In Patient Fibroblasts With Pathogenic Mitochondrial Dna Mutations Causing Leigh Syndrome, Ajibola Bakare

Graduate Theses and Dissertations

Leigh syndrome (LS) is a rare fatal mitochondrial disorder of infants caused by pathogenic mutations in the nuclear (nDNA) or mitochondrial DNA (mtDNA) leading to mitochondrial dysfunction. The extent to which pathogenic mtDNA variants regulate disease severity in LS is not well understood. The heterogeneous nature of this disorder, based in part by complex mitochondrial genetics, and the nuclear and mitochondrial cross-talk has made it particularly challenging to investigate and develop therapies for treating LS . While the prognosis is poor, several studies are underway to understand the pathophysiology of LS. This dissertation provides a comprehensive structural and functional analysis …

A Time-Course Characterization Of Muscle Function And Mitochondrial Markers During Colorectal Cancer-Induced Cachexia In Tumor-Bearing Male Mice, Ana Cabrera Ayuso

Graduate Theses and Dissertations

Cachexia is a multisystemic and multifactorial syndrome prevalent in cancer patients. It is clinically defined by involuntary loss of >5% weight in a six-month window, despite nutritional interventions. A negative energy balance characterizes cancer cachexia (CC), it is associated with weakness and fatigue in skeletal muscle. Impaired muscle function is associated with lower quality of life in cancer patients. Defects in mitochondrial function are strongly associated with muscle wasting. This study explored muscular contractile function and mitochondrial quality control (MQC) markers in soleus, gastrocnemius, and tibialis anterior (TA) muscles of C26-induced male tumor-bearing mice during a 25-day time course. It …

Host-Parasite Interactions Within Food Webs, Adam Zvanut Hasik

Graduate Theses and Dissertations

Parasitism is one of the most common life history strategies employed in nature, yet the effects of parasites are often thought to be minimal, and the vast majority of studies fail to consider parasites and their effects on host organisms. This is likely a problem, as the magnitude of parasite-mediated effects on their hosts can be quite large. Additionally, the effects of parasites are known to extend beyond the host to affect other species interactions. I used a series of approaches to gain a more integral understanding of host-parasite interactions by studying (1) the effects of parasites on biotic interactions …

Resistance Screening And Association Mapping For Resistance To The Downy Mildew Pathogen Of Spinach, Dotun Olaoye

Graduate Theses and Dissertations

Spinach is an important cool leafy vegetable cultivated around the world, with large scale production in California and Arizona in the U.S. Spinach is a highly nutritious vegetable beneficial in the human diet. Spinach is affected by a number of biotic stressors. Downy mildew, caused by the oomycete pathogen Peronospora effusa, is a major threat to spinach as it affects the leaf quality and impacts the economic value of spinach. Several efforts have led to the development of resistant genotypes/cultivars to this pathogen. However, few studies have examined the genetics of resistance to the downy mildew pathogen in detail. This …

Biochemical Characterization Of Small Molecule Inhibitor Binding On A Ras Related Gtpase And Its Effector Interactions, Djamali Muhoza

Graduate Theses and Dissertations

The Ras superfamily of GTPases has 167 proteins that are involved in various cellular processes such as proliferation, transformation, migration, and inhibition of cell death. Mutations, abnormal expression, and function of these proteins are observed in many diseases, including several forms of cancer. Even though these GTPases were among the first discovered oncogenes, no successful Ras drug candidate has successfully passed clinical trials. Drugs targeting these proteins have failed mainly because of the complexity of their regulation, their high affinity to GTP, and their structure’s dynamic nature. Recently, novel promising targeting approaches have renewed interest in the Ras drug discovery …

Molecular And Genetic Studies Of Robo2 Transcriptional Regulation In The Central Nervous System Of Drosophila Melanogaster, Muna Abdal Rahim Abdal Rhida

Graduate Theses and Dissertations

Drosophila Robo2 axon guidance receptor is a member of the evolutionarily conserved Roundabout (Robo) protein family that is involved in directing axons that cross the midline to the other side of the animal body. Robo2 roles mainly depend on two factors: The functional domains of the Robo2 protein, which is extensively studied, and the dynamic transcription of robo2 in various subsets of cells throughout embryogenesis which is not fully understood. Thus, knowing robo2 enhancers that transcriptionally regulate robo2 during embryogenesis is significant. To investigate robo2 potential enhancers, we screened 17 transgenic lines of Drosophila that were generated by Janelia Research …

The Biochemical Characterization Of Aza197 And A Ras Related Protein Cdc42, Alix Montoya-Beltran

Graduate Theses and Dissertations

Eukaryotic cells contain an extensive amount of GTP/GDP binding proteins. Proteins known as Ras GTPase primary function as a binary switch, where they cycle from an on and off state when GTP or GDP are bound, respectively. They are known to play a critical role in many cellular functions where a dysregulation could potentially lead to oncogenic behavior or other malignancies. In our laboratory, our focus is the study of a Ras related protein Cell division control 42 homolog (Cdc42) which belongs to the Rho subfamily. Cdc42 plays a critical role in many biological signaling processes; therefore, its uncontrol gene …