Biochemistry, Biophysics, and Structural Biology Commons^™

Spatially Controlled Monolayers For Electrically Switchable Biomolecule Detection, Eduard Lukhmanov

Theses, Dissertations and Capstones

The development of biosensors that are low-waste, highly stable, and possess an ability to be interchanged between capturing and non-capturing configurations is promising for the biodetector field. Stable packing and attachment of the sensor, the ability to create an interchangeable detecting probe of interest relatively easily, and dynamic control of the probe via a reversible bias can provide for that. With the set goals to control all those properties, DNA-dendron conjugate molecules were designed, synthesized in solution, purified, and utilized to make self-assembled monolayers of single-stranded DNA on gold. To be able to manipulate the conjugates’ sensing qualities in the …

Directed Evolution Studies On A Firefly Luciferase Variant To Improve Signal Intensity For In Vivo Bioluminescence Imaging, Allison Racela

Biochemistry, Cellular and Molecular Biology Honors Papers

In previous research, bioluminescence proteins have been used for in vivo bioluminescence deep tissue imaging. A familiar organism that produces bioluminescent light, is a firefly. Firefly luciferase normally produces yellow-green light (λmax ~ 560 nm) with LH2. There are several reasons for improving bioluminescent light to emit in the near-infrared window (nIR) between 650 nm and 900 nm. The main reasons for improving nIR detectability include that the light transmits more efficiently through mammalian tissues due to less light scattering, nIR light is also less likely to be absorbed by hemoglobin, and water. Overall this provides better resolution for deep …

The Role Of Ehd2 In Endothelial Cells, Rachael Judson

Electronic Theses and Dissertations

The role of EHD2 in terms of Cav1 interaction had not been previously characterized and was the main goal of this research. Cav1 has been shown to lead to the ubiquitination of Rac1. Because of this, the role of EHD2 in Rac1 regulation was investigated. An increase in long-term migration in endothelial cells was observed and suggested that EHD2 impacts the RhoA pathway instead of the Rac1 pathway. This lead to the hypothesis that EHD2 controls a part of the RhoA pathway. This hypothesis is supported by the loss of filamentous actin and an increase in serrated junctions in cells …

Characterization Of Cyclopropyl Synthases Involved In The Maturation Of Ribosomally Synthesized And Posttranslationally Modified Peptides, Yi Lien

Electronic Theses and Dissertations

Ribosomally synthesized and post-translationally modified peptides (RiPPs) are a large class of natural products with significant human health implications. RiPPs are synthesized from a genetically encoded precursor peptide that undergoes significant modifications by maturing enzymes, or maturases. Recently, radical-S-adenosylmethionine (rSAM) enzymes have emerged as an important family of RiPP maturases. rSAM enzymes have been shown to install ether, thioether, and carbon-carbon bonds on the precursor peptide. These modifications usually define the backbone structure of the mature RiPP. This thesis describes the characterization of a novel RiPP modification catalyzed by the radical S-adenosylmethionine enzyme TigE. TigE belongs to the TIG biosynthetic …

Inhibition Of De Novo And The Prion-Like Spread Of Amyloidogenesis Using In Vitro And In Vivo Disease Models, Johnson Anazoba Joseph

Electronic Theses and Dissertations

The aberrant fibrous, extracellular, and intracellular proteinaceous deposits in cells, organs and tissues are referred to as amyloids. These deposits are dominated by β-sheet structures that have been implicated in several neurodegenerative diseases and cancer. In this work, the types of amyloidosis studied include Parkinson’s disease (PD) using UA196 and NL5901 strains of Caenorhabditis elegans (C. elegans), Alzheimer’s disease (AD) using GMC101 strain of C. elegans, and cancer-associated mutant p53 aggregation in MIA PaCa-2 mutant cells. Several molecules including SK-129, NS132, NS163, bexarotene, a polyphenol (-)-epi-gallocatechine gallate (EGCG), ADH40, RD148, and RD242 were screened in vitro and in …

Lipophilic Probes For Cellular Ethylene Detection, Morgan R. Brown

Electronic Theses and Dissertations

The structure of ethylene is simple, yet its biological effects are significant. When considering its role in biology it is almost exclusively regarded as a plant hormone. Research on ethylene from plants was progressed by several advancements in analytical instrumentation, from its discovery to elucidation of its signaling pathway. There is currently limited understanding of ethylene’s role in mammals, but evidence suggests that it may be a biomarker for oxidative stress! Additional tools and technology are crucial to study this surprising and important signaling role in mammals. Our group has developed molecular ethylene probes as a strategy to detect ethylene …

The Pathophysiological Mechanisms Of Alzheimer's Disease; Investigating Therapeutic Interventions For Disease Onset, Alexandra A. Sandberg

Electronic Theses and Dissertations

Alzheimer’s Disease is a multifarious disease that progressively affects more people as both the proportion of older adults in the population and life expectancy increase in both the United States and worldwide. This devastating disease is a result of rampant neuronal loss in the memory centers of the brain that robs the independence of those who are diagnosed and places a heavy burden on those who care for them. Traditionally speaking, research has focused on the hallmark pathology of amyloid plaques, targeting them to try and prevent disease onset. However, countless failures in clinical trials aimed at this said pathology …

Cysteine-Tyrosine Crosslink Synthesis In Bf4112 From B. Fragilis, Alex Van Uffelen, Sophie Hruska, David Benson

Summer Research

Redox-active crosslinked amino acids are a class of post-translational modifications that extend protein chemistry. These cofactors occur in fifteen known proteins with high resolution Xray crystallography as the primary method for confirmation. One of those proteins is cytochrome c oxidase (complex IV), where HisTyr (figure 1) is responsible for the high-valent oxidative intermediate in O2 reduction to 2H2O. Cys-Tyr was the first of these cofactors to be identified and is characterized in galactose oxidase (coordinated to a Cu ion) and cysteine dioxygenase (distal to a mononuclear non-heme iron ion).

Cbp60-Db: An Alphafold-Predicted Plant Kingdom-Wide Database Of The Calmodulin-Binding Protein 60 (Cbp60) Protein Family With A Novel Structural Clustering Algorithm, Keaun Amani, Vanessa Shivnauth, Christian Castroverde

Biology Faculty Publications

Molecular genetic analyses in the model species Arabidopsis thaliana have demonstrated the major roles of different CAM-BINDING PROTEIN 60 (CBP60) proteins in growth, stress signaling, and immune responses. Prominently, CBP60g and SARD1 are paralogous CBP60 transcription factors that regulate numerous components of the immune system, such as cell surface and intracellular immune receptors, MAP kinases, WRKY transcription factors, and biosynthetic enzymes for immunity-activating metabolites salicylic acid (SA) and N-hydroxypipecolic acid (NHP). However, their function, regulation and diversification in most species remain unclear. Here we have created CBP60-DB, a structural and bioinformatic database that comprehensively characterized 1052 CBP60 gene homologs …

Antioxidant Biomarkers And Nutraceutical Therapeutics In Neurodegeneration And Neurotrauma, Lilia A. Koza

Electronic Theses and Dissertations

Mild traumatic brain injury (mTBI), yielding a Glascow Coma Scale of 13-15, is the most commonly occurring severity of TBI. Pathology from mTBI consists of blood brain barrier disruption, neuroinflammation, oxidative stress, excitotoxicity, mitochondrial dysfunction, protein aggregation, axonal degeneration, and resulting neuronal death. These processes deplete the body’s endogenous antioxidant system. We report a retrospective analysis of antioxidant blood biomarkers in patients with a history of mTBI from a local sports medicine clinic, Resilience Code. We found persistent sex-specific antioxidant depletions in mTBI patients associated with worsened symptomology.

Certain populations, such as athletes, are at high risk for repetitive mTBI …

Organellar Zn2+ Homeostasis And The Role Of Trpml Channels In Neuronal Lysosome Physiology And Axonal Transport, Taylor Franklin Minckley

Electronic Theses and Dissertations

Zinc (Zn²⁺) is crucial for proper cellular function, and as such it is important to measure and track Zn²⁺ dynamics in living cells. Fluorescent sensors have been used to estimate Zn²⁺ content of subcellular compartments, but little is known about endolysosomal Zn2+ homeostasis. Similarly, although numerous sensors have been reported, it is unclear whether and how Zn²⁺ can be released from intracellular compartments into the cytosol due to a lack of probes that can detect physiological dynamics of cytosolic Zn²⁺. My dissertation started with comparing and characterizing different Zn²⁺ sensors including the …

The Effects Of Neuronal Growth Factors On Lps-Activated Schwann Cells, Caitlyn E. Henry, Peyton Kimmel, Angela Asirvatham Ph.D.

Student Research Poster Presentations 2022

Schwann cells (SCs) are the principal support cells of neurons in the peripheral nervous system, that both myelinate axons for the rapid conduction of electrical impulses as well as assist in axonal repair during nerve injury. During nerve injury, SCs secrete tumor necrosis factor alpha (TNF-α)^1,5,6 and other proinflammatory mediators^1,6, attracting macrophages to the site of injury to induce inflammation and clear myelin debris.^1,6 Once the debris is cleared, the neuron stimulates SC proliferation by secreting neuronal mitogens, such as heregulin^3,4, and an unknown factor that activates the cAMP pathway³, an important …

Simulation Of An Inflammatory Model Using Schwann Cells, Caitlyn Henry, Peyton Kimmel, Angela Asirvatham

Student Research Poster Presentations 2022

During peripheral nerve injury, the myelin surrounding the neuronal axons is damaged, initiating an inflammatory response to remove myelin debris. Once myelin debris is cleared, Schwann cells acquire a proliferating phenotype which allows them to grow and divide so that remyelination can occur. The neuron stimulates Schwann cell division by secreting growth factors, like heregulin, and an unknown growth factor that activates the cAMP pathway. Although the role of cAMP in axonal regeneration is well-known, not much has been explored about its function in Schwann cells during nerve injury and inflammation. To simulate an inflammatory environment, the S16 Schwann cell …

Using Circular Dichroism Spectroscopy To Study Secondary Structure Of Horseradish Peroxidase: A Laboratory Experiment In Biochemistry, Shemaiah Kamran, Sarah E. Bultje, Kumar Sinniah

Summer Research

• We present a laboratory experiment in biochemistry to study the Far-UV Visible secondary structure of a protein (horseradish peroxidase, HRP) that can be adapted for a single-session laboratory experiment or a multiple-session laboratory project.
• A Circular Dichroism (CD) spectrometer provides structural information of proteins as a function of environmental changes such as pH and temperature. We present secondary structural information for the protein, horseradish peroxidase, at pH 3 and pH 7 in the temperature range 30-80° C in phosphate buffered solution (PBS).
• HRP has many applications in biochemistry and biotechnology. It is frequently used as a reporter enzyme in diagnostics …

Characterization Of Cofilin And Its Potential Role In The Epha4 Pathway, Brian Donald Condron

Master's Theses and Doctoral Dissertations

EphA4 is a receptor tyrosine kinase that is responsible for cellular adhesion and locomotion using repulsion signaling in early development of Xenopus laevis. EphA4 regulates cellular locomotion by controlling proteins within its signal transduction pathway, which may include the protein cofilin. Cofilin actively severs and removes actin monomers, thus altering the actin cytoskeleton, leading to the cessation of cellular crawl. During the gastrulation phase of embryonic development, individual cells are relocating to create the three primary germ layers of the organism. Failure of this process to occur results in attrition of the embryos, frequently by way of embryonic exogastrulation. …

Affinity Of Cadmium Versus Zinc For The Carbonic Anhydrase Active Site, Rachel Phan

Honors Scholars Collaborative Projects

Cadmium is a heavy metal found in tobacco plants, nickel-cadmium batteries, and as a byproduct of metal mining. The similarities between the properties of zinc ions and cadmium ions in proteins due to their 2+ charges may cause displacement of zinc by cadmium if encountered and has been shown to do so in several transcription factors. Cadmium’s ability to replace zinc- a metal found in around 3,000 human proteins- is a cause for concern, especially due to its toxicity, long half-life in the body, and larger size.

Carbonic anhydrase is an important metalloprotein protein that relies on a central zinc(II) …

Intestinal Endothelial Cells Promote Hiv Latent Infection In Resting And Activated Cd4+ T-Cells, Nathan Dapprich, Jessica Eddy, Fisher Pham, Anding Shen

Summer Research

No abstract provided.

Recent Strategies For Using Monolithic Materials In Glycoprotein And Glycopeptide Analysis, Allan Alla, Keith Stine

Chemistry & Biochemistry Faculty Works

There is continuous effort towards developing monolithic materials as solid supports for the separation, enrichment, and digestion of glycoproteins. The intention of this review is to discuss and summarize work reported in this area during the period 2015–2021 as a follow-up to our prior review. Reports from the past three decades have already proven the advantages of monolithic materials, such as the ease with which they can be prepared and functionalized, their high permeability and low resistance to mass transfer, and their stability over a wide range of pH. Recent works on glycoprotein analysis introduce different strategies in using monolithic …

The Role Of Dichloro(Ethylenediamine) Platinum Ii In Altering Cellular Iron And Copper Transport, Megan Hall

Mahurin Honors College Capstone Experience/Thesis Projects

Approximately 50% of all chemotherapy cancer patients receive a platinum chemotherapeutic during their treatment. Although these drugs are widely utilized, little is known about the cellular transport of platinum drugs. It is hypothesized that platinum utilizes transporters for other metals to enter the cell. Structural differences between compounds are predicted to affect the compounds’ ability to exploit different transporters. Also, different cell types express different transporters. Therefore, compound structure is expected to influence transport of platinum compounds differently in different cell types. This study investigated the role of the platinum drug cisplatin and platinum compound Pt(en)Cl₂ in altering iron …

Synthetic Design And Anisotropic Conductivities Of Polymeric Mixed Ion- Electron Conductors, Nika Bondar, Abigail Slimp, Patrick Gruoner, Jason Lin

Baker/Koob Endowments Awarded Projects

Our project documented, in extensive detail, the liquid crystalline (LC) assembly pathway from solution to solid state in the supramolecular complexes of the mixed ionic-electronic conducting polymers (MIECPs) prepared from carboxylated poly(3-alkylthiophene) and ionic liquid surfactant. Using UV-visible spectroscopy we have shown that the complexation is accompanied by the surfactochromism showing colorimetric response and conformational transitions as a function of the IL surfactant mole ratio. Additionally, we have demonstrated via Polarized Optical Microscopy (POM), that the equimolar solution exhibits rodlike conformation and its hydrogel spontaneously forms a 2D smectic LC mesophase with a lamellar periodicity. Defect-free LC domains were produced …