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Biochemistry Commons

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2025

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Articles 241 - 270 of 286

Full-Text Articles in Biochemistry

Open Path Spectroscopic Detection Of The Hydroxyl Radical: A Comparison Between Broadband Cavity-Enhanced Absorption Spectroscopy (Bbceas) And Bbceas Coupled With A Fabry-Pérot Interferometer (Bbceas-Fp), Callum Flowerday, Ryan Thalman, Matthew C. Asplund, Samuel A. Badstubner, Adam K. Cook, Philip Lundrigan, Jaron C. Hansen Jan 2025

Open Path Spectroscopic Detection Of The Hydroxyl Radical: A Comparison Between Broadband Cavity-Enhanced Absorption Spectroscopy (Bbceas) And Bbceas Coupled With A Fabry-Pérot Interferometer (Bbceas-Fp), Callum Flowerday, Ryan Thalman, Matthew C. Asplund, Samuel A. Badstubner, Adam K. Cook, Philip Lundrigan, Jaron C. Hansen

ScholarsArchive Data

Data collected by the BBCEAS and BBCEAS-FP instruments described in the paper "Open Path Spectroscopic Detection of the Hydroxyl Radical: A Comparison Between Broadband Cavity-Enhanced Absorption Spectroscopy (BBCEAS) and BBCEAS coupled with a Fabry-Pérot Interferometer (BBCEAS-FP)"


Microbial And Plant Biodiversity In Appalachian Agroecosystems And Their Implications For Soil Health, Kinsey Reed Close Jan 2025

Microbial And Plant Biodiversity In Appalachian Agroecosystems And Their Implications For Soil Health, Kinsey Reed Close

Graduate Theses, Dissertations, and Problem Reports (ETD)

The sustainability of agricultural landscapes depends on understanding the complex interactions between plants, soil, and microbes. In Appalachia, a region shaped by complex terrain and long histories of human and ecological interaction, small family farms produce hay, livestock, and row crops. These agroecosystems, though often treated as “artificial” by many ecologists, have the potential to support both food production and biodiversity conservation if managed with an understanding of ecological complexity. This dissertation examines how plant and microbial diversity interact with soil and management to influence nutrient cycling, soil health, and long-term resilience in Appalachian agricultural systems. A literature review revealed …


The Effect Of Polyethylene Glycol Surface Density Of Dense Brush Gold Nanoparticles On Insulin Fibrillation, Ethan Patrick Grier Jan 2025

The Effect Of Polyethylene Glycol Surface Density Of Dense Brush Gold Nanoparticles On Insulin Fibrillation, Ethan Patrick Grier

Graduate Theses/Dissertations

The development of various neurodegenerative diseases such as Parkinson’s disease and Alzheimer’s disease has been linked to the fibrillation of various proteins within the brain. Parkinson’s disease is specifically linked to the fibrillation of α-Synuclein. During the fibrillation process, the proteins take the form of oligomers, and exposure to these oligomers has been linked to various cytotoxic and neurotoxic effects. Once the fibrillation process is complete, the fibrils made have been shown to be much less toxic than the oligomer stage. This fibrillation process is thermodynamically favorable and is largely irreversible, so one course of action for treatment of these …


Investigations Of Proteins Including Yellow Thermal Protein, Blue Thermal Protein, Lactoperoxidase, And Thyroid Peroxidase, Cammi Dargatz Jan 2025

Investigations Of Proteins Including Yellow Thermal Protein, Blue Thermal Protein, Lactoperoxidase, And Thyroid Peroxidase, Cammi Dargatz

Graduate Theses/Dissertations

This research investigated four different proteins: yellow thermal protein (YTP), blue thermal protein (BTP), lactoperoxidase (LPO), and thyroid peroxidase (TPO). YTP and BTP were both engineered from the extremely stable and non-aggregative thermal green protein (TGP) by mutating one residue each to obtain proteins with shifted spectra while preserving the stability properties observed in TGP. Site-directed mutagenesis (SDM) was utilized to construct YTP by mutating a histidine at residue 197 to a tyrosine (H197Y) and BTP by mutating a tyrosine at residue 67 to a histidine (Y67H). These proteins were expressed in E. Coli and purified with nickel and diethylaminoethyl …


Development Of Cyan And Blue Thermostable Fluorescent Proteins: Characterization And Structural Analysis, Acacia J. Jurkowski Jan 2025

Development Of Cyan And Blue Thermostable Fluorescent Proteins: Characterization And Structural Analysis, Acacia J. Jurkowski

Graduate Theses/Dissertations

Fluorescent proteins are commonly used as cell markers in living organisms. Modifications by mutation can be used to improve the qualities of these proteins including fluorescence, thermostability, pH stability, and chemical stability. The goal of this project is to use mutagenesis to improve the fluorescence of thermostable cyan and blue proteins derived from the thermal green protein (TGP). The first cyan protein developed by the DeVore lab (CTP 0.0) shifted the fluorescence to cyan but decreased the quantum yield (ΦF) to 0.056. Further mutations were incorporated to increase the quantum yield through incorporating hydrogen bonding interactions to the …


Human Serum Albumin Interaction With Organochlorine Pesticides, D. S. Sanford, R. Yadav, A. Mishra Jan 2025

Human Serum Albumin Interaction With Organochlorine Pesticides, D. S. Sanford, R. Yadav, A. Mishra

Journal of the Arkansas Academy of Science

Human serum albumin (HSA) is the most abundant blood plasma protein and plays a crucial role in drug transport and physiological homeostasis. HSA has a highly flexible structure consisting of three domains, each with multiple binding sites lined with hydrophobic and hydrophilic residues. The structural properties of HSA make it a robust reservoir and receptor for various endogenous and exogenous compounds, including therapeutic drugs. Organochlorine pesticides (OCPs) are a subclass of pesticides characterized by their chlorine content. Once widely used, these compounds remain persistent in the environment and biological systems despite regulatory restrictions in many developed countries. The strong ligand-binding …


Long-Term Antibacterial Efficacy Of Silver (I) Cyanoximates Against Streptococcus Mutans Ua159 Biofilm Growth, Tiffany A. Rojas Jan 2025

Long-Term Antibacterial Efficacy Of Silver (I) Cyanoximates Against Streptococcus Mutans Ua159 Biofilm Growth, Tiffany A. Rojas

Honors Program Theses

Streptococcus mutans is the primary causative agent of dental caries due to its ability to form resilient multispecies biofilms. These biofilms promote acid production and degradation of the protective layers of the tooth, making biofilm formation a target for novel treatments. Silver(I) cyanoximates are of interest as alternatives to traditional antimicrobials and antibiotics due to the high UV and heat resistivity as well as poor solubility of the cyanoxime ligand paired with the well-established antimicrobial silver ion. Previous research has shown that silver(I) cyanoximates can effectively inhibit S. mutans biofilm formation after 24 hours in vitro. This study aimed to …


Target Cell-Associated Cd47 Suppresses Nadph Oxidase Activity In Macrophages During Antibody Dependent Cellular Phagocytosis, Seuly Akter Jan 2025

Target Cell-Associated Cd47 Suppresses Nadph Oxidase Activity In Macrophages During Antibody Dependent Cellular Phagocytosis, Seuly Akter

Electronic Theses and Dissertations

CD47-SIRPα signaling is a well-known immune checkpoint that suppresses macrophage-mediated antibody-dependent cellular phagocytosis (ADCP). In this study, we explored how CD47 influences reactive oxygen species (ROS) production driven by Fcγ receptor (FcγR) signaling. Our results show that macrophages produce significantly more ROS when encountering IgG coated target cells lacking CD47.Polarization with IFNγ further amplified this effect. ThusCD47-SIRPα interactions limit phagocytosis and suppress oxidative ROS production by macrophages. We found that CD47 blockade and IFNγ stimulation enhanced ADCP through distinct mechanisms. CD47 blockade removed the inhibitory "don't eat me" signal supporting ADCP and ADROS. Similarly, IFNγ enhances ADCP by upregulating FcγRI …


Bridging The Gap Between Structural And Cellular Biology: Insight Into The Organization Of Glycolytic Enzymes In Cells, Heather Hansen Jan 2025

Bridging The Gap Between Structural And Cellular Biology: Insight Into The Organization Of Glycolytic Enzymes In Cells, Heather Hansen

Graduate Theses, Dissertations, and Problem Reports (ETD)

Glycolytic enzymes are spatially organized in the cytoplasm, and are shown to localize with cellular structures such as the plasma membrane, F-actin, mitochondria, or associate independently within the cytosol. The assembly of these enzymes is hypothesized to regulate pathway flux to meet the energetic needs of the cell. However, it is unclear whether all of these assemblies have the same mechanism of formation or function in the cell. We investigated the role of glycolytic enzyme assemblies in cells, using the glycolytic “gatekeeper” enzyme phosphofructokinase-1 (PFK1). PFK1 is extensively regulated by multiple mechanisms, including over 20 allosteric ligands, post translational modifications, …


Probing The 10-23 Dnazyme Catalytic Core: Insights From Structural And Mechanistic Studies, Evan Rhyse Cramer Jan 2025

Probing The 10-23 Dnazyme Catalytic Core: Insights From Structural And Mechanistic Studies, Evan Rhyse Cramer

Graduate Theses, Dissertations, and Problem Reports (ETD)

The 10-23 DNAzyme is a catalytically active DNA oligonucleotide capable of cleaving RNA at purine-pyrimidine junctions in the presence of divalent metal ions, most notably magnesium. Despite its promise as a programmable RNA knockdown tool, its clinical and biotechnical utility has been hampered by limited structural characterization, low catalytic efficiency under physiological conditions, and poor understanding of its in-cell activity. This dissertation presents a comprehensive framework for the structural and functional analysis of DNAzymes using the 10-23 DNAzyme as a model system. In the absence of high-resolution structures, we first employed detailed in vitro biochemical assays to map essential residues …


Characterization Of P38alpha And Nitric Oxide Synthase 3 Binding, Gillyan M. Jewett Jan 2025

Characterization Of P38alpha And Nitric Oxide Synthase 3 Binding, Gillyan M. Jewett

Master's Theses

P38alpha is a member of the mitogen activated protein kinase (MAPK) family. This family is important for mediating signal transduction pathways through phosphorylation of downstream substrates. Previous work has described the ability of p38alpha to bind and phosphorylate nitric oxide synthase 3 (NOS3) at two sites, the autoinhibitory loop (AI) at S600 and the N-terminal MAPK binding site (NtMAP) at S114. P38alpha has two substrate binding domains, the common docking groove (CD-groove) and a hydrophobic pocket (DEF) that are important in binding and phosphorylating various substrates specific to each pocket. Utilizing biolayer interferometry, this work describes the importance of both …


Green Chelation Strategy For Deashing Of Algal Biomass, Agyare Asante, George Daramola, Ryan W. Davis, Sandeep Kumar Jan 2025

Green Chelation Strategy For Deashing Of Algal Biomass, Agyare Asante, George Daramola, Ryan W. Davis, Sandeep Kumar

Civil & Environmental Engineering Faculty Publications

This study investigated a green chelation strategy for deashing algal biomass using nitrilotriacetic acid (NTA) and deionized water (DI) to enhance its suitability for biofuel and bioproduct applications. Solid-state algal turf scrubber (SS ATS), green algal turf scrubber (ATS), and Scenedesmus were analyzed, with Scenedesmus selected for detailed evaluation due to its high ash removal efficiency. The objective was to optimize a purification process that minimizes ash and heavy metal content while preserving biochemical integrity. Algal biomass underwent sequential washing with DI, NTA, and NTA+DI under varying temperatures (90-130 °C). Analytical techniques including Fourier Transform Infrared (FTIR) spectroscopy, Inductively Coupled …


Environmentally Friendly Chelation For Enhanced Algal Biomass Deashing, Agyare Asante, George Daramola, Ryan W. Davis, Sandeep Kumar Jan 2025

Environmentally Friendly Chelation For Enhanced Algal Biomass Deashing, Agyare Asante, George Daramola, Ryan W. Davis, Sandeep Kumar

Civil & Environmental Engineering Faculty Publications

High ash content in algal biomass limits its suitability for biofuel production by reducing combustion efficiency and increasing fouling. This study presents a green deashing strategy using nitrilotriacetic acid (NTA) and deionized (DI) water to purify Scenedesmus algae, which was selected for its high ash removal potential. The optimized sequential treatment (DI, NTA chelation, and DI+NTA treatment at 90–130 °C) achieved up to 83.07% ash removal, reducing ash content from 15.2% to 3.8%. Elevated temperatures enhanced the removal of calcium, magnesium, and potassium, while heavy metals like lead and copper were reduced below detection limits. CHN analysis confirmed minimal …


Extended Inter-Laboratory Characterization Of The New Coastal Seawater Dissolved Organic Matter Reference Material Trm-0522, Alexander J. Craig, Lydia Babcock-Adams, Maxime C. Bridoux, Charlotte Brun, Juliana D'Andrilli, Aleksandar I. Goranov, Patrick G. Hatcher, Oliver Lechtenfeld, Hang Li, Rebecca Matos, Garrett Mckay, Amy M. Mckenna, Madelyn Miller, Sasha Wagner, Margot E. White, Alexander Zherebker, Jeffrey A. Hawkes Jan 2025

Extended Inter-Laboratory Characterization Of The New Coastal Seawater Dissolved Organic Matter Reference Material Trm-0522, Alexander J. Craig, Lydia Babcock-Adams, Maxime C. Bridoux, Charlotte Brun, Juliana D'Andrilli, Aleksandar I. Goranov, Patrick G. Hatcher, Oliver Lechtenfeld, Hang Li, Rebecca Matos, Garrett Mckay, Amy M. Mckenna, Madelyn Miller, Sasha Wagner, Margot E. White, Alexander Zherebker, Jeffrey A. Hawkes

Chemistry & Biochemistry Faculty Publications

Dissolved organic matter (DOM) reference materials are critical to ensuring reliable comparability of measurements across experiments and between labs. TRM-0522, isolated in 2022 from 45 m deep seawater off of Sweden’s west coast, fills the niche of a previously unavailable coastal marine DOM reference material. After its isolation, we detailed a limited number of metrics for TRM-0522, initially disclosing Orbitrap high-resolution mass spectrometry, nuclear magnetic resonance, carbon proportion, absorbance, and fluorescence data. With TRM-0522 becoming more widely used, a variety of labs have generated different metrics that help to characterize and define the chemical properties of this coastal reference material. …


Experimental Demonstration And Study Of Transmembrane-Electrostatically Localized Protons Prevail, James Weifu Lee Jan 2025

Experimental Demonstration And Study Of Transmembrane-Electrostatically Localized Protons Prevail, James Weifu Lee

Chemistry & Biochemistry Faculty Publications

In this review in relation to some interesting arguments from Silverstein, it is now reaffirmed that the experimental demonstration of transmembrane-electrostatically localized protons (TELPs) was successfully accomplished through 1) using an aluminum film as a TELPs sensor in a biomimetic anode water-membrane-water cathode system, 2) analyzing the water-electrolysis current curve, and 3) measuring bulk liquid phase pH. Formation of induced TELPs was subsequently discovered in an anode water-membrane-water-membrane-water cathode system. The discovery of induced TELPs enabled clean experimental tests on the cation-TELPs exchange process by using sodium bicarbonate or potassium bicarbonate solution in the central liquid chamber. The sodium/TELPs exchange …


Validating A Novel Capability Of Assessing Pathways Of Animal Water Gain And Loss, Zachary T. Steele, Karen Caceres, Zachary A. David, Lisa M. Shollenberger, Alexander R. Gerson, Seth D. Newsome, John P. Whiteman Jan 2025

Validating A Novel Capability Of Assessing Pathways Of Animal Water Gain And Loss, Zachary T. Steele, Karen Caceres, Zachary A. David, Lisa M. Shollenberger, Alexander R. Gerson, Seth D. Newsome, John P. Whiteman

Biological Sciences Faculty Publications

Understanding variations in the routes by which wild animals gain and lose water is challenging, and common methods require longitudinal sampling, which can be prohibitive. However, a new approach uses Δ′¹⁷OBW (Δ′¹⁷O of animal body water), calculated from measurements of δ′¹⁷O and δ′¹⁸O in a single sample, as a natural tracer of water flux. Δ′¹⁷OBW is promising, but its relationship to organismal variables such as metabolic rate and water intake have not been validated. Here, we continuously measured oxygen influxes and effluxes of captive deer mice (Peromyscus maniculatus), and manipulated their water intake and metabolic rate. We used …


Science, Physiology, And Nutrition For The Nonscientist, Judi S. Morrill Jan 2025

Science, Physiology, And Nutrition For The Nonscientist, Judi S. Morrill

Open Educational Resources

A wonderful blend of physiology, nutrition, biochemistry, genetics, biology, evolution, chemistry--what we all need to know as informed citizens. A basic knowledge of the life sciences and how our bodies work--to promote our own good health, especially as we're bombarded with misleading advertisements, soundbites, and the like. DNA fingerprinting, calorie requirements, dietary advice, genetic engineering (including gene editing with CRISPR cas9)--all in an easy-to understand book.


Exploring The Effects Of Road Salt On Earthworm Species, Alea Mry Koston Jan 2025

Exploring The Effects Of Road Salt On Earthworm Species, Alea Mry Koston

Williams Honors College, Honors Research Projects

This study examines the effects of two road salts, sodium chloride (NaCl) and calcium magnesium acetate (CMA), on the health of two earthworm species: Eisenia fetida and Lumbricus terrestris. Over a 4-week period, approximately 168 earthworms were exposed to varying concentrations of either NaCl, CMA, or mixed ratios of both, with a control group included for comparison. The experiment involved monitoring the changes in earthworm weight and measuring their contraction rates to determine physiological responses. Statistical analysis revealed no significant differences in weight or activity between NaCl and CMA treatments for either species. However, higher concentrations of NaCl resulted in …


Expression And Purification Of Cytochrome P450 46a1 For Resonance Raman Spectroscopy, Lauren Jirles Jan 2025

Expression And Purification Of Cytochrome P450 46a1 For Resonance Raman Spectroscopy, Lauren Jirles

Williams Honors College, Honors Research Projects

Researchers are targeting cytochrome P450 46A1 (CYP46A1), an enzyme critical for brain cholesterol homeostasis, as a potential therapeutic approach for neurological diseases. CYP46A1 plays a key role in cholesterol turnover in the brain by catalyzing the conversion of cholesterol to 24S-hydroxycholesterol (24HC) and is linked to Alzheimer’s disease pathophysiology. Given its critical role in brain health, CYP46A1 represents a promising target for therapeutic intervention in neurological disorders. The goal of this project was to express the CYP46A1 protein in GC5 E. coli cells and purify the protein using chromatographic techniques including affinity and ion exchange chromatography. Ultraviolet-Visible (UV-Vis) spectroscopy was …


Impact Of Tetrahydrocannabinol (Thc) On Daphnia Magna Heart Rate, Ashley Cosgrave Jan 2025

Impact Of Tetrahydrocannabinol (Thc) On Daphnia Magna Heart Rate, Ashley Cosgrave

Williams Honors College, Honors Research Projects

Marijuana (Cannabis) is currently federally illegal within the United States and classified as a Schedule I drug. This leaves a large research gap on the impacts of Tetrahydrocannabinol (THC) use. Daphnia magna are frequently used as a model organism for the human heart and toxicology screenings due to their myogenic heart, similarities in physiological pathways, and sensitivity to toxins. As such, in order to bridge the research gap and uncover potential use of Daphnia magna as a model organism for humans in regard to impact on heart rate, we hypothesized that if Daphnia magna possess CB1 receptors or an equivalent …


The Bacteriostatic, Regenerative, And Immunomodulatory Properties Of Extracellular Matrix Particles For Lung Injury, Keera P. Rhoads Jan 2025

The Bacteriostatic, Regenerative, And Immunomodulatory Properties Of Extracellular Matrix Particles For Lung Injury, Keera P. Rhoads

Theses and Dissertations

Acute respiratory distress syndrome (ARDS) is a prevalent, life-threatening lung condition, affecting nearly 200,000 Americans annually, with a 40% international mortality rate. There is no cure for ARDS, and current pharmacological treatments have limited effectiveness. Symptoms can be mitigated with mechanical ventilation, though this often leads to ventilator-induced lung injuries (VILI) and puts critically ill patients at risk of infections, including ventilator-associated pneumonia (VAP). A promising therapeutic is the extracellular matrix (ECM), a complex network of structural proteins and bioactive molecules that has been shown to have anti-inflammatory properties and prevent fibrosis. We aim to utilize the regenerative and immunomodulatory …


Near-Infrared Hemicyanine And Bodipy Sensors For Monitoring Mitochondrial Viscosity In Live Cancer Cells, Drosophila Melanogaster Larvae, And Adpkd Kidney Tissue, Joseph Peters Jan 2025

Near-Infrared Hemicyanine And Bodipy Sensors For Monitoring Mitochondrial Viscosity In Live Cancer Cells, Drosophila Melanogaster Larvae, And Adpkd Kidney Tissue, Joseph Peters

Dissertations, Master's Theses and Master's Reports

Two near-infrared fluorescent sensors, sensor A and sensor B, were synthesized and characterized. Sensor A was a hemicyanine derived structure, and sensor B was a BODIPY derived sensor. The sensors were tested to measure their ability to monitor viscosity, and sensor A was used to monitor viscosity in live cells. Both sensors were found to be effective in monitoring the viscosity level through optical measurements with glycerol. Sensor A was found to be successful in monitoring mitochondrial viscosity in HeLa MBA-MD-453 and MDA-MB-231 cell lines. It was also successful in monitoring viscosity in Drosophila melanogaster larvae as well as …


Extracellular Vesicles Released By All Patients Contain Hne-Adducted Proteins: Implications Of Collateral Damage, Jenni Ho, Suriyan Sukati, Tamara Taylor, Sherry Carter, Brittany Fuller, Amy Marmo, Caryn Sorge, John A. D'Orazio, D. Allan Butterfield, Subbarao Bondada, Heidi Weiss, Daret K. St. Clair, Luksana Chaiswing Jan 2025

Extracellular Vesicles Released By All Patients Contain Hne-Adducted Proteins: Implications Of Collateral Damage, Jenni Ho, Suriyan Sukati, Tamara Taylor, Sherry Carter, Brittany Fuller, Amy Marmo, Caryn Sorge, John A. D'Orazio, D. Allan Butterfield, Subbarao Bondada, Heidi Weiss, Daret K. St. Clair, Luksana Chaiswing

Markey Cancer Center Faculty Publications

Off-target neuronal injury is a serious side-effect observed in cancer survivors. It has previously been shown that pediatric acute lymphoblastic leukemia (ALL) survivors have a decline in neurocognition compared to healthy age-matched counterparts. Elevated oxidative stress has been documented to be a mediator in off- target tissue damage in cancer survivors. Early detection of oxidative stress markers may provide an opportunity to prevent off-target tissue damage. Extracellular vesicles (EVs) have surfaced as a potential diagnostic tool due to molecular cargo they contain. We investigated the potential for EVs to be a sensitive indicator of oxidative stress and off-target tissue damage …


The Adiponectin-Pparγ Axis In Hepatic Stellate Cells Regulates Liver Fibrosis, Shangang Zhao, Qingzhang Zhu, Wang-Hsin Lee, Jan-Bernd Funcke, Zhuzhen Zhang, May-Yun Wang, Qian Lin, Bianca Field, Xue-Nan Sun, Guannan Li, Mbolle Ekane, Toshiharu Onodera, Na Li, Yi Zhu, Christine M. Kusminski, Terry D. Hinds Jr., Philipp E. Scherer Jan 2025

The Adiponectin-Pparγ Axis In Hepatic Stellate Cells Regulates Liver Fibrosis, Shangang Zhao, Qingzhang Zhu, Wang-Hsin Lee, Jan-Bernd Funcke, Zhuzhen Zhang, May-Yun Wang, Qian Lin, Bianca Field, Xue-Nan Sun, Guannan Li, Mbolle Ekane, Toshiharu Onodera, Na Li, Yi Zhu, Christine M. Kusminski, Terry D. Hinds Jr., Philipp E. Scherer

Markey Cancer Center Faculty Publications

Hepatic stellate cells (HSCs) are key drivers of local fibrosis. Adiponectin, conventionally thought of as an adipokine, is also expressed in quiescent HSCs. However, the impact of its local expression on the progression of liver fibrosis remains unclear. We recently generated a transgenic mouse line (Lrat-rtTA) that expresses the doxycycline-responsive transcriptional activator rtTA under the control of the HSC-specific lecithin retinol acyltransferase (Lrat) promoter, which enables us to specifically and inducibly overexpress or eliminate genes in these cells. The inducible elimination of HSCs protects mice from methionine/choline-deficient (MCD) diet-induced liver fibrosis, confirming their causal involvement in fibrosis development. We generated …


Urobilin Derived From Bilirubin Bioconversion Binds Albumin And May Interfere With Bilirubin Interacting With Albumin: Implications For Disease Pathology, Kevin I. Williams, Priyanka Suryadevara, Chang-Guo Zhan, Terry D. Hinds Jr., Zachary A. Kipp Jan 2025

Urobilin Derived From Bilirubin Bioconversion Binds Albumin And May Interfere With Bilirubin Interacting With Albumin: Implications For Disease Pathology, Kevin I. Williams, Priyanka Suryadevara, Chang-Guo Zhan, Terry D. Hinds Jr., Zachary A. Kipp

Markey Cancer Center Faculty Publications

Background/Objectives: Bilirubin is a hydrophobic molecule that binds the carrier protein albumin for transport through systemic circulation. Bilirubin is cleared from the body through the liver and excreted into the intestines, where the microbiota modifies the chemical structure, forming urobilin, which can be reabsorbed into circulation by the hepatic portal vein. Urobilin has no known function. It is also unknown whether urobilin binds albumin for transport in circulation. We hypothesized that because of the likeness of their chemical structures, urobilin would also bind albumin like bilirubin does. Methods: First, we used in silico docking to predict if urobilin would bind …


Dissecting The Biophysical Mechanisms Of Oleate Hydratase Association With Membranes, William A. Lathram, Robert J. Neff, Ashley N. Zalla, James D. Brien, Vivekanandan Subramanian, Christopher D. Radka Jan 2025

Dissecting The Biophysical Mechanisms Of Oleate Hydratase Association With Membranes, William A. Lathram, Robert J. Neff, Ashley N. Zalla, James D. Brien, Vivekanandan Subramanian, Christopher D. Radka

Markey Cancer Center Faculty Publications

This study investigates the dynamics of oleate hydratase (OhyA), a bacterial flavoenzyme from Staphylococcus aureus, and its interactions with lipid membranes, focusing on the factors influencing membrane binding and oligomerization. OhyA catalyzes the hydration of unsaturated fatty acids, playing a key role in bacterial pathogenesis by neutralizing host antimicrobial fatty acids. OhyA binds the membrane bilayer to access membrane-embedded substrates for catalysis, and structural studies have revealed that OhyA forms oligomers on membrane surfaces, stabilized by both protein-protein and protein-lipid interactions. Using fluorescence correlation spectroscopy (FCS), we examined the effects of membrane curvature and lipid availability on OhyA binding to …


Ciliary Arl14b In Vision, Alexis Breann Crockett Jan 2025

Ciliary Arl14b In Vision, Alexis Breann Crockett

Graduate Theses, Dissertations, and Problem Reports (ETD)

Primary cilia are highly specialized organelles that regulate signaling, trafficking, and sensory perception across multiple tissues, including the retina. The small GTPase ADP Ribosylation Factor-Like Protein 13B (ARL13B) is an atypical ARF-family protein enriched in cilia. ARL13B acts as a guanine exchange factor (GEF) for another small GTPase ARF-like Protein 3 (ARL3). Mutations in ARL13B cause Joubert syndrome, a ciliopathy characterized by brain malformation, developmental delays, and retinal degeneration. Despite ARL13B’s known ciliary localization and clinical relevance, ARL13B’s precise functions in cilia remain poorly defined. This dissertation investigates the cilia-specific roles and GEF-specific roles of ARL13B in photoreceptors using two …


Bacteria-Engineered Vesicles For Cancer Immunotherapy: From Immunomodulation In Vitro To Anti-Tumor Effects In Melanoma Models, Lan Li Jan 2025

Bacteria-Engineered Vesicles For Cancer Immunotherapy: From Immunomodulation In Vitro To Anti-Tumor Effects In Melanoma Models, Lan Li

Theses and Dissertations--Chemistry

Bacterial vesicles hold immense potential in various biomedical fields. Among these, outer membrane vesicles (OMVs) produced by Gram-negative bacteria are the most extensively studied. While the exact mechanism of OMV production remains unclear, numerous environmental factors have been shown to influence both their yield and composition. In this study, we investigated the effect of three different antimicrobial families on OMV production by E. coli. Interestingly, antimicrobials within the same family did not provide the same effects on OMV yield, suggesting that OMV production may not directly correlate with the antimicrobial mechanism of action. OMVs have demonstrated tumor-inhibitory activity in multiple …


Redox Control In A Fused Electron Transfer Flavoprotein From A Thermophilic Archaeon And Expanded Significance Of A Hydrogen Bond From A Conserved Histidine Residue That Contributes To Flavin Redox Tuning And Activation For Covalent Modification, Debarati Das Jan 2025

Redox Control In A Fused Electron Transfer Flavoprotein From A Thermophilic Archaeon And Expanded Significance Of A Hydrogen Bond From A Conserved Histidine Residue That Contributes To Flavin Redox Tuning And Activation For Covalent Modification, Debarati Das

Theses and Dissertations--Chemistry

In absence of O2 as terminal electron acceptors in anaerobic bacteria and archaea, carbohydrate metabolism is 15 times less efficient compared to aerobic energy metabolism resulting in energy deficit conditions. Despite their meager resources these anaerobes were able to generate H2 and a chemiosmotic potential able to drive energy demanding reactions such as CO2 or N2 fixation. These observations raised concerns as production of high energy reductants (H2) from mediocre fuels (NADH) defied the laws of thermodynamics.

In 2008, a known mechanism “electron bifurcation” but with flavins as redox mediators instead of quinones was …


Development And In Vitro Evaluation Of Novel Near-Ir Fluorescent Sensors For Egfr Kinase, Haniyeh Jadidi Jan 2025

Development And In Vitro Evaluation Of Novel Near-Ir Fluorescent Sensors For Egfr Kinase, Haniyeh Jadidi

Graduate Research Theses & Dissertations

This thesis presents the in vitro evaluation of a novel near-infrared (NIR) fluorescent small-molecule probe AB-139 that selectively binds to epidermal growth factor receptor (EGFR) kinase and operates through a turn-on fluorescence mechanism. The sensor addresses several limitations associated with conventional protein-based probes by offering small-molecule specificity, tunable modularity, deep-tissue imaging potential, and reduced background noise. AB-139 comprises four key components: A Zn-phthalocyanine fluorophore that serves as the NIR emission reporter; hydrophilic triethylene glycol chains that enhance aqueous solubility and reduce aggregation; cationic quaternary ammonium groups that facilitate cellular permeability; and a gefitinib-derived recognition anchor that targets the intracellular ATP-binding …