Biochemistry, Biophysics, and Structural Biology Commons^™

Expression Levels Of Heat Shock Protein 72 And Their Correlation With Biomarkers Of Renal Function Among Hispanic Construction Workers Exposed To Ambient Heat In El Paso, Texas, Maria Fuentes

Open Access Theses & Dissertations

Heat shock proteins (HSP) are intracellular molecular proteins that are upregulated in response to cellular stress, including heat exposure. Through their protective functions, HSP help maintain protein structure, prevent protein denaturation, and preserve cellular homeostasis during states of physiological stress. Because of their cytoprotective properties, HSP have emerged as potential biomarkers for detecting early signs of tissue injury and predicting clinical outcomes associated with heat related illnesses (HRI), including acute kidney injuries (AKI). AKI is a leading cause of hospitalizations due to heat stress exposure and heat stroke. In the absence of early detection and effective therapeutic interventions, AKI may …

Assessing The Use Of Exon-Skipping Morpholino Antisense Oligonucleotides Targeting The Different Sumo Paralogs As Enhancers Of The Antitumor Activity Of Chemotherapeutic Agents, Andrea Teresa Garcia-Morin

Open Access Theses & Dissertations

Post-translational modifications (PTMs) are critical regulators of protein function, stability, and localization, with SUMOylation emerging as a key modulator of cellular stress response and survival in cancer. Non-small cell lung cancer (NSCLC) is characterized by heightened dependence on SUMOylation to sustain pro-survival signaling, DNA repair, and resistance to chemotherapy. This dissertation investigates a novel chemosensitization strategy based on the splice-switching of SUMO transcripts in NSCLC cells using exon-skipping morpholinos (ESMs), which redirect splicing toward non-conjugatable SUMO alpha isoforms, thereby reducing global SUMOylation. We hypothesized that decreasing global SUMOylation through forced alternative splicing of SUMO transcripts would impair the stress-protective functions …

Novel Roles Of G-Beta-Gamma Signaling In Microtubule Dynamics And Neurodegeneration, Diana I. Olivas

Open Access Theses & Dissertations

Neurodegenerative disorders (NDDs), including Alzheimer's disease (AD), are characterized by progressive neuronal dysfunction, cytoskeletal disruption, and cognitive decline. Although Tau hyperphosphorylation and neurofibrillary tangle (NFT) formation are classical hallmarks of AD, emerging evidence suggests that microtubule (MT) dysfunction may precede and occur independently of Tau pathology. Understanding upstream regulators of MT dynamics is therefore critical for elucidating early mechanisms of neurodegeneration. Previous work from our laboratory demonstrated that G protein βγ (Gβγ) subunits directly interact with tubulin and promote MT assembly. However, the mechanism of Gβγ signaling in neuronal cytoskeletal stability and neurodegeneration remained poorly understood. The present study investigated …

Drug Repurposing Against Giardia Targeting Lipid Rafts, Extracellular Vesicles, And Sphingolipid Synthesis, Breanna Chantal Pence

Open Access Theses & Dissertations

Giardia lamblia is a protozoan parasite responsible for the intestinal disease giardiasis worldwide. Giardia is one of the major intestinal parasites in the world, with over 500,000 new cases annually. Symptoms of giardiasis include diarrhea, abdominal pain, and nausea. Children are particularly vulnerable to giardiasis, with cases of malnutrition, stunted growth, and cognitive impairment in countries where the disease is endemic. Giardia consists of two morphologic forms: an infective cyst which transmits the disease and a motile trophozoite which attaches to the epithelium of the small intestine during infection. Metronidazole is a common treatment for giardiasis, but cases of toxicity …

Design And Optimization Of Peptide Inhibitors Targeting Kinesin: Molecular Modeling Studies And Virtual Screening For Therapeutic Candidate Development, Maraf Mbah Bake

Open Access Theses & Dissertations

Kinesins are ATP-driven molecular motors essential for intracellular transport and mitotic spindle assembly, and their mechanochemical behavior has been extensively characterized through computational tools. The first project reviews decades of advances in molecular dynamic simulations, including all-atom and coarse-grained molecular dynamics, Markov state models, Brownian dynamics, and free-energy approaches, which have collectively deepened our understanding of conformational transitions, microtubule-binding interfaces, and ligand interactions, especially for the mitotic motor Eg5. The second review examines the rapid emergence of quantum computing as a transformative technology for drug discovery, highlighting key historical milestones, recent progress in hybrid quantum-classical algorithms, quantum-enhanced docking, and quantum …

Navigating The Challenges Of Coccidioides Surveillance: Insights From The Environment Of El Paso County, Texas, Tanzir Hossain

Open Access Theses & Dissertations

Coccidioidomycosis, or Valley fever, is a fungal infection resulting from the inhalation of spores from the Coccidioides species (C. immitis and C. posadasii), native to arid areas of the Western Hemisphere. Coccidioidomycosis presents considerable health hazards and can be fatal. It affects between 206,000 and 360,000 individuals annually, leading to 700 to 1,100 fatalities in the United States alone. In response to these issues, extensive research has concentrated on therapeutic goals for this infectious disease. Nonetheless, more limited research has focused on the environmental detection of its causative fungi, which is crucial for forecasting treatment needs and formulating preventive strategies. …

Regulation Of Ccr7 Signaling Events By G-Protein-Coupled Receptor Kinases 2 And 3, Anahi Sanchez

Open Access Theses & Dissertations

G protein-coupled receptors (GPCR) can bind multiple ligands, leading to differential signaling events termed biased signaling. C-C chemokine receptor 7 (CCR7) is a GPCR known to have biased signaling between the two ligands it binds to, CCL19 and CCL21. Binding of C-C Chemokine Ligand 19 (CCL19) promotes a high level of CCR7 phosphorylation, while CCL21 leads to a much lower level of CCR7 phosphorylation; findings observed in HEK and dendritic cells. GPCR kinases (GRKs), which can control the phosphorylation patterns of a GPCR, are hypothesized to regulate biased signaling of a receptor. GRK expression differs between cell lines and cell …

Intratumoral Fibrin As A Novel Immunomodulatory Factor In Pancreatic Ductal Adenocarcinoma, Mazharul Karim

Open Access Theses & Dissertations

In-situ coagulation is a common clinical feature of pancreatic ductal adenocarcinoma (PDAC) that presents a highly thrombotic and crosslinked insoluble fibrin (x-fibrin)-laden tumor stroma (FibTS). However, the specific impact of FibTS on immune cells behavior remains largely unexplored in this poorly infiltrated tumor. We aimed to elucidate how FibTS in PDAC regulates immune cell infiltration, polarization, and crosstalk that favors immunosuppressive microenvironment and tumor growth. We characterized human PDAC tissues by multiplex immunostaining and checked the spatial distribution of immune cells based on the presence of x-fibrin. We investigated how FibTS influences the infiltration of tumor-associated macrophage (TAM) and T-cell …

Multiscale Integration Of Receptor-Ligand Dynamics Into Discrete And Continuous Tumor Growth Models With Application To Tyrosine Kinase Inhibitor Treatment, Romasa Qasim

Open Access Theses & Dissertations

The epidermal growth factor (EGF) receptor cascade plays a crucial role in the survival and proliferation of tumor cells. Tyrosine kinase inhibitors (TKIs) are a class of drugs that inhibit epidermal growth factor receptors (EGFRs), thereby preventing the downstream signal transduction. Despite their importance, models that link spatial receptor dynamics to tumor growth remain scarce. Further, TKIs act through selective mechanisms, inhibiting active, inactive, or all receptor states, which poses a challenge to traditional modeling approaches.

We propose to numerically study two mathematical models incorporating receptor-dynamics into cancer models to describe the impact of EGFR overexpression and TKIs. The first …

Jak1 V658f Drives Oncogenic Transformation Via Transcriptional Reprogramming Independent Of Y598 Phosphorylation And Canonical Jak-Stat Signaling, Omar Javier Rodriguez Moncivais

Open Access Theses & Dissertations

T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive and complex malignancy that accounts for 15% of pediatric acute lymphoblastic leukemia (ALL) cases in the United States. Tyrosine kinases control critical cellular processes, including the development, survival, and activation of T cells, and are established drivers of leukemia.Tyrosine kinases involved in hematological disorders include receptor tyrosine kinases and non-receptor tyrosine kinases family members such as SRC, ABL, FAK, and Janus kinases (JAKs). This study primarily focused on JAK1 gain-of-function (GoF) mutations. These mutations are recognized as hyperactivating mutations, maintaining kinase activity of JAKs on and essentially keeping downstream signaling effectors, like …

Ccr7 Regulated Mechanisms That Limit The Adaptive Immune Response, Jaisel Amilcar Cervantes

Open Access Theses & Dissertations

C-C chemokine receptor 7 (CCR7) is critical in guiding T cell migration within the thymus and peripheral lymphoid tissues, shaping the adaptive immune response by promoting central tolerance and regulating immune homeostasis. Although its role in lymphocyte trafficking is well established, the molecular mechanisms by which CCR7 influences thymocyte development and T cell receptor (TCR) repertoire formation remain less understood. This study examines how CCR7 deficiency impacts thymic selection, TCR diversity, and the signaling events that shape repertoire restriction. Using a homozygously deleted CCR7 murine model, we found that the absence of CCR7 results in a less restricted TCR repertoire …

Functionalized Carbon Quantum Dots: A Promising Nanomaterial For Investigating Their Potential In Neurodegenerative Disease Treatment, Sherin M. El Morsy

Open Access Theses & Dissertations

Neurodegenerative diseases such as Parkinson's Disease (PD), Alzheimer's Disease (AD), and Huntington's Disease (HD) remain incurable, despite extensive research into therapeutic development. In the United States of America, the annual cost of PD and AD in terms of patient care and lost productivity is approximately $200 billion. Consequently, there is a critical and unaddressed need for the development of innovative drugs and drug delivery systems that can decelerate, stop, or ideally reverse neurodegenerative diseases. The dissertation presented here focuses on devising strategies to target PD through multiple mechanisms, including the inhibition of protein aggregation and the reduction of oxidative stress. …

Characterization Of The Androgen Receptor H1-H3 Loop As A Putative Fkbp Regulatory Surface, Isela Rodriguez

Open Access Theses & Dissertations

Prostate Cancer (PCa) is one of the most common life-threatening malignancies diagnosed among American men. Initiation and progression of PCa are dependent upon androgen receptor (AR) regulated genes. Functional receptor conformation is influenced by the cooperation of chaperone and cochaperone proteins including the 52 and 51 kDa FK506 binding proteins (FKBP52 and FKBP51). FKBP52 is known for being a positive regulator of AR, PR (progesterone receptor), and GR (glucocorticoid receptor) activity, whereas FKBP51 negatively regulates steroid hormone receptor activity. As a result, these two proteins have become highly promising therapeutic targets for the disruption of mechanisms important in several endocrine-related …

Assessing Nordihydroguaiaretic Acid Properties And Its Potential Therapeutic Effect For Glioblastoma, Jose Arturo Guerrero

Open Access Theses & Dissertations

This study employs a combination of theoretical and experimental analysis to spectroscopically investigate the biomechanistic structure relationship and therapeutic effects of the Nordihydroguaiaretic Acid (NDGA) chemical derived from the Larrea Tridentata plant. These relationships are crucial for understanding NDGA's efficacy in disease prevention, treatment, and potential toxicological effects. While the medicinal and antiviral properties of the NDGA have been studied extensively, there remains a gap in optically identifying and reporting its structural changes. The current research successfully reveals evident trends in NDGA's vibrational signatures, particularly highlighting the absence of the Raman feature at 780 〖cm〗^(-1) as indicative of a fully …

Repositioning Propranolol To Block Mitogenic Signaling In Breast Cancer, Alexa Noel Montoya

Open Access Theses & Dissertations

Breast cancer is the second most diagnosed cancer among women and is about 30% of all new cases of female cancers each year. It is projected that 1 in 8 every U.S. woman (about 13%) develop invasive breast cancer over the course of her lifetime. While advances in cancer research have made it possible to elucidate several breast cancer genomic subtypes, and develop new novel therapies, many of these agents are associated with significant toxicity, as well as high costs. A retrospective cross-sectional study of 404 breast cancer patients was performed to determine the effect of β-blocker usage on tumor …

Interfacial Interactions Between Engineered Nanoplastics And Biological Systems: Towards An Atomic And Molecular Understanding Of Plastics- Driven Cellular Dyshomeostasis, Afroz Karim

Open Access Theses & Dissertations

The persistent presence of micro (nano) plastics in our environment has raised concerns regarding potential health risks associated with human exposure. With the extensive use of plastic materials and the widespread consumption of plastic-contaminated food items, two types of microplastics, polystyrene (PS) and polymethylmethacrylate (PMMA), have attracted increased attention. While the adverse effects of microplastics on animals and marine life have been extensively studied, their potential impact on human health remains largely unexplored. Specifically, the interaction between microplastics and biomolecules within the human body and their effect on human health have yet to be comprehensively investigated. This dissertation study focuses …

Structural Studies Of The Human Hsp60 And Bacteriophage Phiel Chaperonins, Daniel Han Von Salzen

Open Access Theses & Dissertations

Chaperonins are large protein complexes responsible for the refolding of misfoldedsubstrate. Many mechanisms of the folding process have not been completely elucidated. Here we perform biochemical and structural analysis on two chaperonins, the human mitochondrial Hsp60 and the bacteriophage EL encoded PhiEL, to better understand key structural components and their purpose to the chaperonin function. Hsp60 plays an essential role in maintaining protein within the mitochondrial matrix. Despite its importance, the detailed mechanism of ATP hydrolysis and the role of the C-terminal tail remains unresolved. Here we show that the C-terminal tail not only acts as a sensor for the …

Functional Characterization Of The Human And Murine Schlafen Family Group Iii, Carlos A. Valenzuela

Open Access Theses & Dissertations

The Schlafen (SLFN) family of proteins are known for being encoded by interferon stimulated genes. The family is divided into three groups (I, II, III), for which the largest in size belong to the subgroup III. In humans, group III has the most members (SLFN5, SLFN11, SLFN13 and SLFN14); there is no member of group I and only one member of group II (SLFN12). All human SLFNs belonging to group III have been reported to impair viral protein expression or infection across a variety of viruses. The antiviral function is mediated in SLFN11 and SLFN13 by their tRNase activity, and …

X-Ray Crystal Structure Of E399q,E708q Ecm16 Double Mutant, Gileydis Guillama

Open Access Theses & Dissertations

The use of antibiotics has undoubtedly been a boon for humanity in combating infections and microbial threats. However, their widespread utilization has contributed to the emergence and spread of antibiotic resistance, which now poses a significant public health challenge. Streptomyces bacterium, produce diverse secondary metabolites with antibacterial, antifungal, antiviral, antitumoral, and immunosuppressant activities. Among these compounds is echinomycin, a nonribosomal peptide antibiotic synthesized by Streptomyces lasalocidi, which inhibits DNA replication and transcription by intercalating the DNA duplex at CpG steps. A gene called ecm16 was identified in the echinomycin biosynthetic gene cluster, which provides echinomycin self-resistance. Ecm16 recognizes DNA duplexes …

Structural Study Of Lsd13 And Lsd14 Type I Modular Polyketide Synthases From The Lasalocid A Biosynthesis Pathway, Dayan Viera

Open Access Theses & Dissertations

Bioactive natural products often possess a complex structure and have a large size which make their chemical synthesis highly challenging. To overcome this challenge, we are developing a biosynthetic method for production of natural products and their analogs. This technology is expected to decrease the synthesis time from years to weeks and reduce the cost of drug production by multiple orders of magnitude. We are investigating the biosynthesis pathway of lasalocid A, an anticancer antibiotic, to develop this technology. Specifically, we aim to characterize the enzymes structurally and biochemically in this pathway, thus paving the way for their rational engineering. …

Functional Analysis Of The Gamma-Aminobutyric Acid Type A Receptor Subunit Alpha-1 (Gabra1) Gene During Zebrafish Development., Nayeli Gabriela Reyes-Nava

Open Access Theses & Dissertations

The GABRA1 gene encodes for the alpha-1 (α1) subunit of the Gamma-Aminobutyric acid type A receptor (GABAAR), which are the primary modulators of synaptic inhibition in the central nervous system (CNS). Alpha-1 subunits are essential for maintaining the normal function of native receptors and contribute to over 60% of all GABAARs in the CNS. Remarkably, a broad spectrum of neurodevelopmental and epilepsy-associated disorders have been linked with mutations in the GABRA1 gene. However, the developmental, behavioral, and molecular mechanisms underlying GABRA1-associated epileptic disorders remain to be fully understood. Hence, the overarching goal of this dissertation is to investigate the behavioral …

Microscopic And Spectroscopic Analysis Of Nordihydroguaiaretic Acid Effect On Astrocytes, Lizbeth Vanessa Martinez Lopez

Open Access Theses & Dissertations

Astrocytes, one of the most abundant cell components in the central nervous system (CNS), have been a research target in the last few years. Several studies have found that astrocytes are not only mere supporters of neurons but also of essential processes developed in the CNS. Their malfunction could induce neurodegenerative diseases and brain tumors. Thus, further understanding of astrocytes and their role is of high interest to develop possible new treatments and methods of disease diagnosis, especially in brain cancer. The plant Larrea tridentata (La Gobernadora in Mexico or Creosote bush in the United States) is known to have …

Developing And Applying Computational Methods On Biomolecules, Shengjie Sun

Open Access Theses & Dissertations

Computational biophysics is an interdisciplinary subject that uses numerical algorithms to study the physical principles underlying biological phenomena and processes. Electrostatic interactions play an important role in computational molecular biophysics and their potential impact on disease mechanisms. At distances larger than several Angstroms, electrostatic interactions dominate all other forces, while the alteration of short-range electrostatic pairwise interactions can also have significant effects. The dual nature of electrostatic interactions, being dominant at long-range and specific at short-range, underscores their profound implications for wild-type structure and function. Any disruption of the complex electrostatic network of interactions may abolish wild-type functionality and could …

Carbon Quantum Dots' Effects On The Structure And Function Of Neurodegenerative And Non-Neurodegenerative Associated Proteins, Shima Masoudi Asil

Open Access Theses & Dissertations

Protein folding is an important physical process in which the sequences of polypeptides fold into a three-dimensional biological active structure. Misfolding is the conversion of a protein molecule into a structure unlike the native form, and therefore misfolded proteins have a strong tendency to aggregate and make fibrils. Amyloid aggregation is constituted by misfolded amyloidogenic proteins. Neurodegenerative diseases, such as Alzheimer’s Disease (AD), stem from the abnormal accumulation of harmful proteins, including Amyloid-ß peptides, tau protein, and the presynaptic protein α-synuclein in the nervous system. Alzheimer's disease is the most common neurodegenerative disorder that causes memory and learning deficits and …

Analysis Of The Electrostatic Characteristics Of The Zika Virus Capsid Using Computational Methods, Cassandra Guadalupe Del Rio De Avila

Open Access Theses & Dissertations

Zika virus (ZIKV) is a flavivirus that is usually transmitted through the bite of infected mosquitoes. This virus can cause a variety of neurological disorders, the most common being Guillain-Barré syndrome in adults. Moreover, it is of great concern in pregnant women, since can cause deformities in the brain and other organs of newborns.Studying the structural characteristics of the virus during its mature and infectious phase can provide crucial information on the mechanisms by which it enters and replicates within host cells, as well as its evolution, transmission, and interaction with other living organisms. The symmetric pattern present in the …

Exploring The Anticancer Mechanism Of Thienopyrazole Derivative Tpz-1 In Acute Myeloid Leukemia, Jessica Dyanne Hess

Open Access Theses & Dissertations

Anticancer drug discovery is a time and resource-consuming process for which exceedingly reliable and efficient modern approaches are needed. Phenotypic drug screenings can generate highly potent and innovative drug candidates; however, deconvolution of the drugâ??s target often presents significant barriers to drug development. To overcome this hurdle, we have originally combined in vitro and in silico analyses to uncover the molecular mechanism(s) driving the anticancer activity of the uniquely structured small molecule drug candidate, Tpz-1. Our study revealed that Tpz-1 is a multitargeted agent which induces the programmed death of HL-60 acute myeloid leukemia cells primarily through disruption of microtubule …

Development Of A Ph-Triggered Cargo Delivery System With Esxa Mutants, Shuchen Chen

Open Access Theses & Dissertations

Tuberculosis (TB) is a communicable disease caused by Mycobacterium tuberculosis (Mtb). It was the leading cause of human death generated by a single infectious agent before the Coronavirus (COVID-19) pandemic. Mtb has a special mechanism to evade the hostâ??s immune system and utilize macrophages as reservoirs. Latent TB infections have been a threat to public health. Liposome has been widely used for drug delivery. Immunoliposomes are special liposome carriers coated with ligands, such as antigens, targeting certain cells or organs to regulate the uptake of liposome. By constructing the liposome components, or surface modification, cargo release of liposome can be …

Eluication Of Lipid Metabolic Pathways In Differentiating Giardia Lamblia Using High Resolution Mass Spectrometry, Cameron Ellis

Open Access Theses & Dissertations

Giardia lamblia is an intestinal protozoan found worldwide, including the U.S. This parasite exists in two morphologic stages - a replicative trophozoite and a relatively dormant yet viable cyst. While exposures of cysts to gastric acid during passage through the human stomach induces excystation, factors in the small intestine, where trophozoites colonize trigger encystation or cyst formation. Transformation into cyst stage is essential for Giardia to survive in the environment for months before infecting new hosts. Because of its small genome size (11.7 Mb), metabolic pathways in Giardia are highly reduced. As far as lipid metabolism is concerned, only limited …

Characterization Of Esxa/Esxb Heterodimer Membrane Interaction With A Novel Popc/Popg Liposome Model, Salvador Vazquez Vazquez Reyes

Open Access Theses & Dissertations

EsxA and EsxB are co-secreted as a heterodimer and have been shown to play critical roles in phagosome rupture and translocation of Mycobacterium tuberculosis into the cytosol. Current in vitro studies support a model in which the EsxA:EsxB heterodimer is dissociated upon acidification, which might allow EsxA insertion into liposome membranes. While the membrane permeabilizing activity (MPA) of EsxA has been well characterized in liposomes composed of di-oleoyl-phosphatidylcholine (DOPC), the MPA of EsxA:EsxB heterodimer has not been detected with the DOPC liposome. In this study, we established a new in vitro membrane assay to test the MPA of EsxA and …

Utilizing Computational Methods To Study The Biomolecules, Wenhan Guo

Open Access Theses & Dissertations

COVID-19 is increasingly affecting human health and global economy. Understanding the fundamental mechanisms of Severe Acute Respiratory Syndrome CoronaVirus 2 (SARS-CoV-2) is highly demanded to develop treatments for COVID-19. SARS-CoV and SARS-CoV-2 share 92.06% identity in their N protein RBDs' sequences, which results in very similar structures. However, the SARS-CoV-2 is more easily to spread. Utilizing multi-scale computational approaches, this work studied the fundamental mechanisms of the nucleocapsid (N) proteins of SARS-CoV and SARS-CoV-2, including their stabilities and binding strengths with RNAs at different pH values. Electrostatic potential on the surfaces of N proteins show that both the N proteins …