Biochemistry, Biophysics, and Structural Biology Commons^™

Optimization Of L-Citrulline Production In Corynebacterium Glutamicum, And The Effect Of The Human Small Intestine Environment, Simran S. Ghulldu

Honors Undergraduate Theses

L-citrulline is a crucial amino acid involved in nitric oxide production, which supports cardiovascular health, physical performance, and intestinal well-being. Nitric oxide deficiency is linked to conditions like hypertension, highlighting the need for efficient L-citrulline production. This study attempts to enhance L-citrulline synthesis in Corynebacterium glutamicum, a bacterium widely used in industrial amino acid production, as well as test a The hypothesis is that overexpressing carAB, which encodes carbamoyl phosphate synthetase, will increase carbamoyl phosphate levels and boost L-citrulline production. Two C. glutamicum strains were used: a wild type and the CRBG strain, which has mutations that promote …

Characterization Of Lipids In Tenebrio Molitor Larvae And Pupae Under Various Extraction Methods, Nariman A. Ktil

Graduate Theses, Dissertations, and Problem Reports (ETD)

Tenebrio molitor, or the yellow mealworm is an edible insect widely recognized and consumed for its rich nutritional value. Mealworms are known for their flexible nature of adapting to various environmental conditions and being able to thrive under harsh conditions and low-value wastes. In this paper, our main goal was to investigate the mealworm’s ability to grow and develop while being reared on apple pomace, the biowaste from apple production, and the effect it would have on its nutritional value specifically its lipid profile. Then these reared insects were used for oil extraction and analyzing their fatty acid profiles. …

An Investigation Into How The Prostate And Androgens Mediate Greater Levels Of Uric Acid In Males Compared To Females, Rachel D. King

Graduate Theses, Dissertations, and Problem Reports (ETD)

Chronic elevated circulating uric acid (UA) levels (hyperuricemia) are associated with gout as well as cardiovascular, metabolic, and renal dysfunction. Men have greater mean circulating UA levels than women and are more likely to exhibit hyperuricemia. This may be partly driven by the hormonal regulation of renal UA transporters; however, a direct link between hormones and UA production has not been established. Production of UA is catalyzed by xanthine oxidoreductase (XOR / XDH), which is ubiquitously expressed but has the greatest specific activity in the liver. Interestingly, an extensive gout genome-wide association study (GWAS) recently revealed a robust genetic …

P23h Rhodopsin Accumulation Disrupts Synaptic Protein Levels In Rod Photoreceptors, Samantha Thompson

Graduate Theses, Dissertations, and Problem Reports (ETD)

Rod photoreceptors are specialized neurons located in the retina, the neural tissue that lines the back of the eye. Rod photoreceptors are necessary for dim light and peripheral vision through the photoactivation rhodopsin (Rho). Rho is synthesized in the inner segment of rods before being unidirectionally trafficked to the outer segment. In diseases such as retinitis pigmentosa (RP), Rho trafficking can be disrupted, leading to progressive rod cell death. In many cases of RP, Rho is mislocalized to the rod photoreceptor synapse (“spherule”). The impact of Rho mislocalization on spherule structure and protein organization is poorly understood. We hypothesize that …

Biomechanics Of The Atherosclerotic Lipidome: (Un)Expected Statin Interactions And Membrane Remodelling, Ethan M. Fong

Pomona Senior Theses

Statins interact with lipid membranes in ways that shape their pharmacokinetics, off-target effects, and pleiotropic actions, yet these interactions' mechanical and biophysical consequences remain poorly understood. This thesis employs a combination of surface plasmon resonance (SPR), quartz crystal microbalance with dissipation monitoring (QCM-D), and rheological modelling to characterize how representative statins intercalate within biomimetic supported lipid bilayers (SLBs) of healthy and diseased composition. SPR reveals that lipophilic statins exhibit higher apparent affinities and slower dissociation kinetics, especially in cholesterol- and anionic lipid-rich membranes. QCM-D analyses demonstrate that statins alter membrane mass, dissipation, and interfacial stiffness in a statin- and membrane-dependent …

Temporal Dynamics Of Programmed Genome Rearrangement In Sea Lamprey Embryogenesis: A Deep Learning & Lightsheet Imaging Approach To Studying Early Developmental Transitions, Kasturi Rajandran

Theses and Dissertations--Biology

Programmed genome rearrangement (PGR) in the sea lamprey (Petromyzon marinus) leads to the elimination of ~0.5Gb (20%) of the germline genome during early embryogenesis, yet its timing relative to the maternal-to-zygotic transition (MZT) remains unclear. In this study, we imaged embryos cleared at 3-hour intervals (up to 72 hours post fertilization (hpf)) using high-resolution lightsheet fluorescence microscopy and a custom deep-learning image-analysis pipeline (~80% accuracy) to quantify nuclei and micronuclei counts. Micronuclei, which are the hallmarks of PGR first appear between 24 to 27hpf (vs ~36hpf previously reported) indicating PGR starts earlier than previously reported in the sea …

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

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

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

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 …

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′¹⁷O_BW (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′¹⁷O_BW 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 …

Functional Analysis Of Ligand Binding Domain 2 Of Outer Surface Protein C Of Borreliella Burgdorferi, Gavin Z. Chambers

Theses and Dissertations

Lyme disease, caused by the spirochete Borreliella burgdorferi, is the most common vector-borne infection in North America. A critical determinant of early mammalian infection is outer surface protein C (OspC), a highly variable lipoprotein that is indispensable for spirochete survival but whose precise function remains unresolved. OspC has been proposed to mediate diverse roles, including complement evasion, adhesion, tissue dissemination, and antiphagocytic activity, supporting the view that it is a multifunctional virulence factor. Structural studies have identified two putative ligand-binding domains (LBD1 and LBD2), with LBD2 forming a solvent-exposed crown at the membrane-distal end of the OspC dimer.

To …

Epigenetic Potential Remains Stable Over 100 Years After Introduction, Danielle Dawkins

College of Graduate Studies: Theses & Dissertations

Introduced species provide important insights into organismal behavioral responses. Epigenetic mechanisms are one of the various ways in which behaviors can be modified, particularly through DNA methylation. Through such mechanisms, phenotypic changes can occur in response to environmental changes, allowing an organism to be more plastic. Epigenetic potential (EP) represents the capacity for an organism to be epigenetically modified, and can be measured by counting CpG motifs; cytosine adjacent to guanine within a DNA sequence. Phenotypic plasticity as it relates to EP has been studied extensively in the house sparrow (Passer domesticus), a globally introduced songbird. It is …

Assessment And Health Benefit Of Vitamin C Using A549 Cell, Yetunde Adepoju

College of Graduate Studies: Theses & Dissertations

Vitamin C (ascorbic acid) is a vital micronutrient recognized for its antioxidant capacity and essential bodily functions, such as collagen formation, neurotransmitter activity, and regulation of the immune system. This study explores how vitamin C can protect and potentially heal cells under oxidative stress and inflammation, using A549 cells, a human lung epithelial cell line, as the model system. The cells were exposed to varying concentrations of vitamin C dissolved in water, DMSO, and 5% DMSO. To assess the outcome, cell viability was measured with an MTT assay. In addition, the expression of key genes related to oxidative stress and …

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 …

Interfacing Neural Models: Biocompatibility And Fabrication Of A Flexible, Self-Folding Microelectrode Array, Fernando A. Pesantez Torres

Electronic Theses & Dissertations (2024 - present)

Neurodegenerative diseases pose a formidable challenge in modern medicine, necessitating the development of advanced research tools that can elucidate their complex pathophysiology. Recent advancements in neurodegenerative disease research have led to the development of three-dimensional (3D) neurodegenerative organoids using human induced pluripotent stem cells (hiPSCs). These organoids closely mimic human brain architecture and functionality, providing a valuable tool for understanding complex diseases. Additionally, the ability to generate and study brain organoids consistently and in large quantities holds potential for a controlled in vitro setting and high-throughput drug screening. However, these models are complex systems requiring specialized maintenance, analysis, and manipulation …

Nature, Nurture, And Serial Murder: A Biocriminological Analysis Of Jeffrey Dahmer And Aileen Wuornos, Dori W. Jal

Honors Thesis

In recent years, there has been an increase in public fascination with serial killers, however current criminological explanations continue to focus on social and psychological factors, lacking commentary on potential biological implications. This thesis addresses a gap in the literature by examining how biological processes, specifically epigenetic, neurobiological, and endocrinological mechanisms, interact with environmental stressors to shape serial homicidal behavior. The goal is to determine whether serial murder can be more effectively understood through a biosocial framework that integrates biological vulnerability with lived experience, rather than relying on singular explanatory models.

Using a qualitative multiple-case study methodology, this research analyzes …

Unleashing Serine Palmitoyltransferase In Test Tubes And Mice, Matthew W. Peart

Theses and Dissertations

Canonically known both for structural contributions to lipid bilayers and roles in cell signaling, the sphingolipids comprise a dynamic, multifaceted class of molecules which are studied to understand homeostatic cell biology as well as pathophysiology. Sphingolipids contribute to tissue-specific structures such as myelin, a multilayer membrane that allows for rapid conduction of action potentials along neuronal axons. All sphingolipids are downstream products of the rate-limiting and initiating enzyme in the de novo sphingolipid synthesis pathway, Serine palmitoyltransferase (SPT). Demonstrative of its status as the enzyme that catalyzes a crucial step in a biochemical pathway, SPT activity is strictly regulated. This …

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

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

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 …

Ocean Acidification Mitigation: Potential Expansion Of Sav Restoration Strategy In The Chesapeake Bay, Cree N. Taylor

UROP Posters

Zostera marina is a species of marine macrophyte that has been largely prioritized in past submerged aquatic vegetation (SAV) restoration initiatives within the Chesapeake Bay because of its 1) previous abundance, 2) demonstrated carbon burial abilities, and 3) observed ability for meadows of Z. marina to ameliorate low pH conditions. Due to the temperature variability and poor water quality associated with anthropogenic disturbances in the Chesapeake Bay, Z. Marina beds have experienced several die-off events with limited capacity for regrowth. This systematic review explored the possible benefits of focusing future SAV recovery initiatives on ensuring a diverse variety of SAV …

Analysis Of Differential Gene Expression In Androgen-Independent Clones Derived From The Mycap Pca Cell Line, Jessie L. Tignor, Melanie Sinanian, Richard Inho Joh, David Gewirtz, Jason Reed

UROP Posters

Androgen deprivation therapy (ADT) is a primary treatment strategy for prostate cancer (PCa), yet many tumors eventually develop androgen independence, leading to treatment resistance. To investigate the molecular changes underlying this transition, we analyzed differential gene expression in four androgen-independent (AI) clones derived from the Myc-CaP prostate cancer cell line using RNA sequencing. Gene expression profiles were compared to the parental Myc-CaP line, and differentially expressed genes (DEGs) were identified using DESeq2 and edgeR. The AI clones exhibited significant downregulation of senescence-associated genes, including Ezh2 and lamin B1, suggesting a loss of senescence-related chromatin repression. Additionally, upregulation of Wnt pathway …

Electrochemical Detection Of Prostate Cancer—Associated Mirna-141 Using A Low-Cost Disposable Biosensor, Alexander Hunt, Gymama Slaughter

Center for Bioelectronics Publications

Prostate cancer is the second leading cause of cancer-related deaths among men in the United States. The early detection of aggressive forms is critical. Current diagnostic methods, including PSA testing and biopsies, are invasive and often yield false results. MicroRNA-141 (miRNA-141) has emerged as a promising non-invasive biomarker due to its elevated levels in the urine of patients with metastatic prostate cancer. Here, a low-cost, paper-based electrochemical biosensor for the sensitive detection of miRNA-141 in synthetic urine is reported. The device employs inkjet-printed gold electrodes on photopaper, functionalized with thiolated single-stranded DNA-141 capture probes for specific target recognition. The biosensor …

Technological Development Of In-Cell Nmr: Microfluidic, Metabolomic, And Fluxomic Approaches, Nicholas Sciolino

Electronic Theses & Dissertations (2024 - present)

In the fields of structural biology, metabolomics, and fluxomics, there is a driving, technique-based concern when it comes to high-resolution spectrometry and its marriage to biological and physiological relevance. Sample preparation often involves cellular perturbation, lysate separation schemes, combinations with non-biological reagents, and timeline slack. Conceptually, the farther we get from the cell, the greater the potential disparity between what exists in vivo and our in vitro manipulations. This is particularly true when seeking to collect data on transfected targets of interest, and on sensitive metabolic equilibria that occur on the order of minutes. The question remains: if we are …

Conserved A-Rich Regions In The 3’ Utr Of Zika Virus Differentially Affect Viral Gene Expression, Kristen Kaytes

Electronic Theses & Dissertations (2024 - present)

Following its discovery in 1947, Zika virus garnered little attention in the global stage until a rapidly spreading epidemic brough the virus to the global stage in 2015. Continuous advances in research have begun to further the understanding of the molecular biology of Zika virus, however much is still unknown. Much of our understanding of the virus comes from cross reference to other viruses within the same family, such as Dengue virus and West Nile virus. A commonality of these viruses is that they resemble cellular mRNAs and have a single-stranded positive-sense RNA genome that contains a 5’-cap but lacks …

Investigating Rna Dysfunction Of Inherited Neuromuscular And Neurodevelopmental Disease, Jacob H. Schroader

Electronic Theses & Dissertations (2024 - present)

ITPase deficiency is a rare but fatal, autosomal recessive enzyme deficiency involving encephalopathy, microcephaly, congenital cataracts, hypotonia, developmental delay, and dilated cardiomyopathy. Within a decade since the original description of the severe form in humans, there are huge gaps in the field regarding the underlying molecular mechanisms driving pathogenesis resulting from ITPase deficiency. Past studies have focused on characterization of the organism level ITPase-deficient phenotype, but the molecular and cellular characterization remains to be fully described. Due to the biochemical function and established biological role of the ITPase enzyme, investigation into the consequences of inosine accumulation and misincorporation into RNA …

Synthesis And Assessment Of Biobased Acrylated Epoxidized Soybean Oil Resins For Stereolithography 3d Printing Of Microfluidic Devices, Natalie S. Romero Figueroa

College of Graduate Studies: Theses & Dissertations

This research focuses on the development and characterization of a biobased photocurable resin synthesized from soybean oil for use in stereolithography (SLA) 3D printing of microfluidic devices. The study explores a sustainable alternative to petroleum-based resins by performing an acrylation reaction on epoxidized soybean oil (ESO) to produce acrylated epoxidized soybean oil (AESO), which was then formulated into a photocurable resin with the addition of a photo initiator. The fabrication process involved designing microfluidic molds in SolidWorks and printing them using an Elegoo Mars 4 SLA printer under various exposure and layer thickness parameters. The printed samples consisted of microchannels …

Enhancing The Mechanical Properties Of Sla 3d-Printed Bio-Resin From Linseed Oil Using Cellulose And Lignin Biopolymers, Chukwunonso A. Ikedionu

College of Graduate Studies: Theses & Dissertations

Abstract

This research explores the development of bio resin from linseed oil by the process of epoxidation and acrylation to produce acrylated epoxidized linseed oil (AELO). Lignin and cellulose biopolymers were added as reinforcement at varying weight fractions of 1 wt.%, 2.5 wt.%, and 5 wt.%, and their mechanical performance was compared against pure AELO. The formulations were printed using an Elegoo SLA 3D printer to create standardized test specimens like tensile bars, compression cylinders, and hardness blocks, which were all prepared according to the ASTM testing standard.

The results indicate that reinforcement effects depend on both filler type and …

Development Of Dna Nanoswitches With Aptamer Based Detection For Thrombin, Camryn A. Beckles

Electronic Theses & Dissertations (2024 - present)

Bio-transducers are devices capable of converting the binding signals from molecular recognition events into readable signals for analytical detection. There is a need for modular bio-transducers that can specifically detect a wide range of analytes using a unified readout technique, as this approach could dramatically reduce costs of healthcare diagnostics and environmental monitoring.

To create such a modular transducer, the molecular recognition properties of aptamers will be used and integrated with the already established biosensing capabilities of DNA nanoswitches that reconfigure their shape in the presence of their target molecule. In this design, the detector strands of the nanoswitch will …