Biochemistry, Biophysics, and Structural Biology Commons^™

Refinement And Application Of The Absorption Cross-Section Of Molecular Bromine With Relevance To Atmospheric Chemistry, Callum Flowerday, Ryan Thalman, Jaron C. Hansen, Eric T. Sevy, Jason J. Sorensen, Matthew C. Asplund

ScholarsArchive Data

Defined Br2 XS - is the defined absorption cross-section using the UVvis spectrophotometer.

BBCEAS - This is raw absorption data measured using the BBCEAS (see article for details).

UVvis raw - This is the raw absorption data measured using the UVvis spectrophotometer.

A Hormone-Dependent Trna Half Promotes Cell Cycle Progression Via Destabilization Of P21 Mrna, Takuya Kawamura, Megumi Shigematsu, Yohei Kirino

Department of Biochemistry and Molecular Biology Faculty Papers

tRNA halves are among the most abundant short non-coding RNAs in the cellular transcriptome. Here we report that in androgen receptor-positive LNCaP prostate cancer cells, the hormone-dependent 5'-tRNALysCUU half promoted cell proliferation by facilitating cell cycle progression. Global mRNA profiling upon the 5'-tRNALysCUU half depletion revealed that the mRNA of p21, a negative regulator of the cell cycle, is post-transcriptionally destabilized via a 5'-tRNALysCUU half-driven mechanism. YBX1, identified as a protein interacting with 5'-tRNALysCUU half in the cytosol, was shown to stabilize p21 mRNA. Specific sequences resembling the 5'-tRNALysCUU half, located in the 3'-UTR of p21 mRNA and termed LL588, …

A Novel Approach To Treat Trastuzumab Resistant Her2+ Breast Cancer: Activation Pkcδ, Maria Grazia Mejia Monroy

Master's Theses

In the United States, approximately one in eight women will be diagnosed with invasive breast cancer in her lifetime and one in forty will die from breast cancer. From among all the different subtypes of breast cancer, HER2+ can be found in approximately 20% of breast cancer tumors. HER2 overexpression has been associated with an aggressive form of breast cancer, increasing the risk of metastasis or recurrent tumors in 50% of patients. The standard of care for HER2 positive breast cancer, trastuzumab, has been effective for some patients; however, others develop resistance over time, leading to disease progression and metastasis. …

Pyruvate Dehydrogenase Kinase 4 Mediates Sex Specific Outcomes In Sepsis Induced Cardiomyopathy, John Yap

Dissertations

During sepsis, males often experience worse cardiac outcomes than females. Here, we identified pyruvate dehydrogenase kinase 4 (PDK4) as a key contributor to this disparity. PDK4 is a mitochondrial protein that regulates glucose utilization by inhibiting pyruvate dehydrogenase (PDH). Using a mouse model of endotoxemia, we induced acute inflammation with a sublethal dose of lipopolysaccharide (LPS), which caused cardiac dysfunction and significantly increased myocardial PDK4 expression in males but not females. Cardiac-specific PDK4 overexpression promoted LPS-induced cardiac dysfunction in both sexes, whereas cardiac-specific PDK4 knockout provided protection. In wild-type males, LPS disrupted cardiac metabolism by decreasing PDH activity and fatty …

Breaking The Rules: Post-Translational Modifications And Proteome Dynamics During Anoxia, Chelsea Jordan Hughes

Dissertations and Theses

Most organisms are ill-equipped to survive anoxia, but some organisms have developed molecular strategies to mitigate the cellular stressors associated with a lack of oxygen. While it is established that anoxic survival is contingent on metabolic suppression, it is unclear what mechanisms support this change in gene expression. Gene expression is regulated by a variety of mechanisms within the cell, including alteration of chromatin structure through histone modifications and protein modifications which contribute to the ever-changing proteomic landscape of the cell. Protein modifications such as ubiquitylation can lead to the degradation of proteins, while modifications to transcription factors can change …

United Seas For Resilient Reefs: A Blueprint For Coral Conservation Through International Cooperation, John J. Bohorquez, Maoz Fine, Dana I. Grieco, David A. Gill, Ali Al-Swalimih, Jacqueline Padilla-Gamino, Isaiah W. Bolden, Margaux Hein, Callum Backstrom, Melanie Mcfield, Raphael Martinez, Benjamin Midberry, Fahd Al-Guthmy, Ellen K. Pikitch, Natalia Benejam, Chen Azulay, Britt Ronen, Oren Levy, Anne Mcelroy, Karine Kleinhaus

School of Marine & Atmospheric Sciences Faculty Publications

Coral reefs are one of Earth’s most vital and threatened ecosystems. They protect coastlines, generate billions of dollars of tourism revenue, support valuable fisheries, and contribute to the development of vital medicines. Yet half of the world's coral reefs have been lost in the last 50 years, and 90% of remaining reefs are projected to die off by the middle of this century, mainly due to warming seas from climate change.

Despite these challenges there is reason for hope. Some coral reefs – such as in the northern Red Sea and Gulf of Aqaba – have demonstrated remarkable resilience to …

Enhancing Stability And Emissions In Metal Halide Perovskite Nanocrystals Through Mn2+ Doping, Thi Thu Trinh Phan, Thi Thuy Kieu Nguyen, Trung Kien Mac, Minh Tuan Trinh

Chemistry and Biochemistry Student Research

Metal halide perovskite (MHP) nanocrystals (NCs) offer great potential for high-efficiency optoelectronic devices; however, they suffer from structural softness and chemical instability. Doping MHP NCs can overcome this issue. In this work, we synthesize Mn-doped methylammonium lead bromide (MAPbBr₃) NCs using the ligand-assisted reprecipitation method and investigate their structural and optical stability. X-ray diffraction confirms Mn²⁺ substitution at Pb²⁺ sites and lattice contraction. Photoluminescence (PL) measurements show a blue shift, significant PL quantum yield enhancement, reaching 72% at 17% Mn²⁺ doping, and a 34% increase compared to undoped samples, attributed to effective defect passivation and …

Isolation And Enumeration Of Salmonella Enterica From Fresh Lettuce (Lactuca Sativa L.) Leaves And Its Susceptibility To Different Washing Protocols, Meinard Talplacido, Angella Melissa Carlos, Bryan Rey Oliveros, Ida Dalmacio

The Philippine Agricultural Scientist

Lettuce is one of the most consumed fresh produce items in the country, but it also serves as a vehicle for human pathogens, posing a risk of foodborne illness. This study used conventional microbiological and molecular analyses to obtain the concentration and prevalence of Salmonella enterica in fresh Green Ice and Iceberg lettuce leaves from selected supermarkets in Los Baños, Laguna, Philippines. The efficacy of different household washing procedures in reducing S. enterica on lettuce leaves was also investigated. Of the 19 composite Green Ice lettuce and 21 composite Iceberg lettuce samples tested, 5.26% and 4.76%, respectively, were contaminated with …

Effects Of Water Deficit Stress And Mycorrhiza, Azotobacter Chroococcum, And Azospirillum Lipoferum Biofertilizers On Yield And Morphological Traits Of Wheat (Triticum Aestivum L.) Cultivars, Mehdi Rashnou, Farshid Aref, Bahram Amiri, Masoud Rafiee, Mahdi Zare

The Philippine Agricultural Scientist

Crop production in various parts of Iran faces significant constraints due to insufficient water availability, which is a major challenge to agricultural productivity. To study the effects of water deficit stress on shoot and root growth characteristics and seed yield of different wheat (Triticum aestivum L.) cultivars, an experiment was conducted using a randomized complete block design with a split-plot arrangement and 3 replications. The main factor was irrigation treatments (full irrigation during the growing season [S1], water withholding after flowering [S2], and water withholding after grain filling at the milk stage [S3]). The secondary factors were wheat cultivars …

Elucidating The Roles Of Eukaryotic Initiation Factors Involved In Dap5 Mediated Translation, Jacob Nk Quartey

Dissertations, Theses, and Capstone Projects

Translation initiation in eukaryotes is a highly regulated process essential for accurate protein synthesis. It is a dynamic process that involves a complex interplay between messenger RNAs (mRNAs), ribosomal subunits, and a host of initiation factors, ensuring precise start codon selection and the subsequent assembly of the translation machinery. This process has well been known to be mediated by the eukaryotic Initiation Factor (eIF4F), which consists of the cap binding protein eIF4E, the scaffolding protein eIF4GI, and the helicase factor eIF4A.The recognition and binding of eIF4E to the m⁷G cap structure of the mRNA is essential for the …

Biophysical Analysis Of S100a12 And The Nucleosome Core Particle, Christopher Diforte Jr.

Dissertations, Theses, and Capstone Projects

Calcium signaling and chromatin remodeling are fundamental regulatory processes that control protein activity and gene expression, respectively. This thesis investigates the molecular mechanisms by which local ligand binding and structural perturbations propagate allosteric effects across larger protein systems, using two distinct yet mechanistically analogous models: the calcium binding protein S100A12 and the nucleosome core particle. These studies are unified by a shared emphasis on how physical forces govern biological function.

In the first part, we explore calcium mediated allostery in S100A12, focusing on the distinct roles of its two EF-hand calcium binding loops (EF-I and EF-II). Through a combination of …

Kinetic Analysis Reveals T6a-Protein Specificity For T6a And Hn6a Trna Modifications, Cassandra Mae Harker

University Honors Theses

Transfer RNA (tRNA) is essential for accurate translation of genetic information and plays a role in cellular processes such as lipid aminoacylation and bacterial conjugation. Base modifications help tRNA fold correctly and function properly. An important base modification, N6-threonylcarbamoyladenosine (t6A) occurs at position A37 in the anticodon-stem-loop of tRNA. This modification is crucial for decoding ANN codons. Interestingly, an Archeal organism, Methanocaldococcus jannaschii, can have either t6A and hydroxynorvalylcarbamoyl-6- adenosine (hn6A) modification at the same position on tRNAs. As Tsa proteins catalyze the formation of both t6A and hn6A modifications, this raises the question of whether discrimination between these …

Investigating A Link Between Dna Repair And Dna Replication In Escherichia Coli Using A Bacterial Two-Hybrid System, Lo Cooper

University Honors Theses

Cells rely on nucleotide excision repair (NER) to remove bulky DNA lesions, such as those caused by UV light. In Escherichia coli, NER involves the UvrABC complex, and includes two main pathways, global genomic repair and transcription-coupled repair (TCR). While TCR, which preferentially removes lesions that block RNA polymerase on the transcribed strand of active genes, is well studied, less is known about whether a similar coupling between repair proteins and replisomes blocked by damaged DNA exists. Such a process has been suggested by a high throughput interactome study, using the replisome subunit HolC as bait and the damage …

Structural Studies Towards The Mechanism Of Scanning And Initiator Trna Recruitment During Eukaryotic Translation Initiation, Da Cui

Dissertations, Theses, and Capstone Projects

The central dogma, proposed by Francis Crick in 1958, marks the direction of the flow of genetic information: from DNA to DNA (DNA replication), DNA to RNA (transcription), and RNA to protein (translation). Each of these is tightly regulated and important for cells and organisms to function correctly, grow, and reproduce.

In the eukaryotic system, the initiation stage of translation is the first, the rate-limiting, and the most regulated stage. It involves direct regulation of multiple eukaryotic initiation factors (eIFs), scanning factors such as DHX29, and other factors such as Poly-A binding protein (PABP). It starts with the small subunit …

Evaluation Of Nature-Based Engineering Stream Restoration Of Plaster Creek Through Leisure Creek Condominium Association, Julie Wildschut, Rebecca Evenhouse, Andrea Lubberts, Dave Warners, Haley Weesies

Faculty and Professional Research

When land that was once covered with vegetation and soil becomes dominated by impervious concrete and rooftops, the amount of water infiltrated by the ground plumets. As a result, most suburban areas contribute to the impairment of streams by adding excess water, nutrients, and pollutants to nearby waterways each time it rains. One harmful result of this is the erosion of stream banks. The rapid influx of water that occurs after rain events can destabilize and erode stream banks, resulting in excess sediment in the water. One location where this happened very prominently was a section of Plaster Creek which …

Genetic Factors Of Campylobacter Jejuni Required For Its Interactions With Free-Living Amoeba, Deepti Pranay Samarth, Asim Z. Abbasi, Young Min Kwon

Poultry Science Faculty Publications and Presentations

Acanthamoeba, a free-living amoeba ubiquitous in environmental water, has been considered as the environmental reservoir of certain bacterial pathogens, including Campylobacter jejuni, an intracellular human pathogen causing self-limiting gastroenteritis. Acanthamoeba-C. jejuni interaction mechanisms may help clarify how the otherwise fastidious bacterium C. jejuni survives in environmental waters. In this study, we constructed single deletion mutants of C. jejuni strain 81-176 for the 10 selected genes (motAB, ciaB, kpsE, virB11, cheY, flaAB, cstII, docB, sodB, and cadF) previously shown to be important for the interaction (invasion and intracellular survival) of C. jejuni with mammalian hosts. We used a modified gentamicin protection …

Fire Fossils: Biomineral Infrastructures In Untangling Climates, Tanmayee More

Masters Theses

Diatoms drift, sediments sink, wildfires generate their own weather. Lightning strikes can blast sand into glass, and microscopic organisms do the same in the cold recesses of the ocean. What alchemies and metabolisms catalyze space, time, and energy? What are the thermodynamics of infrastructure in Climate Change?

Places, materials, and beings are afterimages. Through alchemical experiments, and multi-scalar imaging, I develop simulations of wildfires, and their profound, reverberating effects. In this thesis, a glass-meets-landscape experimental process enters these obscured conditions and renders new material relations for the built environment.

Tree Story, Jia Hu

Masters Theses

What is Nature?

Nature is a system of intelligence. It means designing for efficiency—often by learning from strategies that have evolved over time. In my research, I use patterns to interpret and decode nature.

To explore nature, I began with the red cedar tree, aiming to simulate and predict its growth patterns—forms shaped by both internal biology and external forces. By analyzing its geometry, I sought to understand how trees embody the dynamic relationship between organism and environment. These patterns reveal the adaptive logic of life.

Patterns are central to understanding nature. While tree geometry may appear chaotic, it follows …

Structural And Functional Lessons Learned About Regulation Of Enterotoxigenic E. Coli Virulence Regulatory Factor, Rns, Jessica Dianne Tolbert

Dartmouth College Ph.D Dissertations

Antibiotic resistance has exacerbated the global health crisis of diarrheal diseases caused by enteric bacterial pathogens. Investigating pathogens, such as Enterotoxigenic Escherichia coli (ETEC) and Vibrio cholerae (cholera), helps to uncover mechanisms for the inhibition of virulence gene expression. A notable member of the AraC transcription factor family in ETEC, Rns, regulates virulence factors including pili and fimbriae, which are essential for adherence and colonization of the intestinal epithelial layer. This microbe–host interaction initiates the release of toxins, leading to the water and ion loss in clinically diagnosed as diarrhea.

In the canonical N-terminal domain of Rns, mutagenesis of the …

Characterization Of Sars-Cov-2 Replication And Transcription Complexes Via Structural And Evolutionary Approaches, Amelie Ghirardo, Ben Shabatian, Avishai Aghelian, Kyle Tau, Eleonora Gianti

Undergraduate Research

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused around 700M cases and over 7M COVID-19-related deaths recorded worldwide (World Health Organization, March 2025). Aiming to effectively combat this and other disease-causing Coronaviruses (CoV), unprecedented research efforts led to the development of new vaccines and antiviral therapies. Due to emergence of variants of concern (VOCs) with increased transmissibility, immune evasion from vaccination, and potential to resist the available treatments, SARS-CoV-2 continues to represent a major threat to global health. Hence, there is a pressing need to discover new antivirals with broad-spectrum efficacy against multiple SARS-CoV-2 variants and related CoVs. This project …

Ion-Dna Interactions As A Key Determinant Of Uracil Dna Glycosylase Activity., Sharon N Greenwood, Alexis N Dispensa, Matthew Wang, Justin R Bauer, Timothy D Vaden, Zhiwei Liu, Brian P Weiser

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Because of their ubiquitous presence, ions interact with numerous macromolecules in the cell and affect critical biological processes. Here, we discuss how cations including Mg²⁺ alter the enzymatic activity of a DNA glycosylase by tuning its affinity for DNA. The response of uracil DNA glycosylase (UNG2) to Mg²⁺ ions in solution is biphasic and paradoxical, where low concentrations of the ion stimulate the enzyme, but high concentrations inhibit the enzyme. We analyzed this phenomenon by modeling experimental data with a statistical framework that we empirically derived to understand molecular systems that display biphasic behaviors. Parameters from our statistical …

Sequence Conservation Of Suppressor Of Ikk Epsilon Phosphorylation Sites, Kaydence M. Isaacs

Undergraduate Honors Theses

Suppressor of IKK epsilon (SIKE) is a protein that is implicated in immune response signaling pathways. SIKE interaction networks suggest roles in cell motility and macromolecular complexes mediating kinase/phosphatase activity. In this project, we aim to better understand the function of SIKE by analyzing amino acid sequences across different species. In human SIKE, viral infection leads to phosphorylation of SIKE at defined serine residues. Comparing SIKE sequences, and specifically these phosphorylation sites, allows us to discover its ancestral connections to innate immune function. This has particular applications in bridging the evolutionary gap between fungi and metazoa SIKE sequences. Multiple sequence …

Generation Of A Transgenic Vector For The Purpose Of Transforming Charcoal Rot Resistance Into Soybeans (Glycine Max), John M. Bear Jr

Electronic Theses & Dissertations

Charcoal rot, caused by Macrophomina phaseolina, is among the most devastating fungal pathogens affecting G. max, particularly in drought-susceptible regions such as the midwestern United States. Traditional agricultural practices have included crop rotation and irrigation, which have proved ineffective or economically unfeasible. Charcoal rot infects over 500 other species of plants and can overwinter as dormant sclerotia which can germinate once soybeans are re-planted and infect young plants. As a result, transgenic solutions have offered a promising alternative for the development of disease-resistant soybeans. This thesis documents the construction of a transgenic vector to express BOZO, a …

Trade-Off Between Limonene & Geraniol-Based Reprocessable And Non-Reprocessable Epoxy Thermosets: Role Of Aliphatic Diamines In Polymer Networks Design, Priyankkumar Kanubhai Patel

Electronic Theses & Dissertations

The growing demand for sustainable materials, driven by environmental concerns and the rapid depletion of fossil fuels, has garnered significant attention in the fabrication of bio-based epoxy thermosets as renewable alternatives to petroleum-derived thermosetting polymers. The present study focuses on the synthesis and characterization of epoxy prepolymer resins derived from limonene and geraniol via a two-step process, followed by the fabrication of thermally cross-linked flexible epoxy thermoset films using various traditional aliphatic diamine curing agents, namely 1,2-ethylenediamine (EDA), 1,4-butylenediamine (BDA), and 1,6-hexamethylenediamine (HDA). Additionally, the incorporation of cystamine, a disulfide-containing diamine, enabled the formation of a covalent adaptable network through …

The Effects Of Ataxin-1 Overexpression In The Central Nervous System On Specific Behavioral And Physiological Characteristics Of Drosophila Melanogaster, Sydney Davis

Theses and Dissertations

Spinocerebellar ataxia type 1 (SCA1) is a dominantly inherited neurodegenerative disease caused by a CAG repeat expansion in the ataxin-1 gene, which results in an abnormally long polyglutamine tract. Similarly, overexpression of wildtype Ataxin-1 (wt-Atx-1) in Drosophila melanogaster leads to neurodegeneration, reduced lifespan, and impaired negative geotaxis. Observations include disruptions in sleep-wake cycles, increased oxidative stress biomarkers (like protein carbonyls), and dysregulation of developmental genes such as armadillo (arm) and nemo kinase (nmo). Additionally, elevated expression of SUMOylation-related genes (Aos-1, Uba2, and dSmt3 or dSumo) and increased SUMO protein levels indicate enhanced SUMOylation in the brain. Quantitative analysis of neuronal …

Exploring Sexual Dimorphism In A Drosophila Melanogaster Model Of Spinocerebellar Ataxia Type 1, Madelyn Hunter

Theses and Dissertations

Neurodegenerative diseases affect over 36 million people and are characterized by loss of motor control, neuronal degradation, and behavioral changes. The most common of these diseases exhibit sexually dimorphic effects. In this study, Spinocerebellar ataxia type 1 (SCA1) was modeled in the Drosophila central nervous system using the yeast hybrid UAS/GAL4 system. Locomotor activity and clock gene expression was monitored for male and female SCA1 and control flies. Clock genes such as per, tim, Clk, and cyc were monitored over a 24-hour period using qRT-PCR, and distinct sexual dimorphism was detected in locomotor activity and in gene expression for SCA1 …

Assessing The Effects Of Streptozotocin-Induced Hyperglycemia On Amyloid Beta Accumulation And Cognitive Behavior In A Mouse Model Of Alzheimer’S Disease-Related Pathology, Andrew Adonay Ortiz

UNLV Theses, Dissertations, Professional Papers, and Capstones

Alzheimer’s disease (AD) is an irreversible and devastating neurodegenerative disease characterized by progressive synaptic, dendritic, glial, and neuronal loss, collectively leading to impairments in learning, memory, and deterioration of cognitive and behavioral functions. AD is the most common form of dementia accounting for 60-80% of all cases. AD affects approximately 7 million Americans and is the 6th leading cause of death in the US. Furthermore, by 2050, the US is projected to spend over $1.1 trillion on AD-related treatments. Pathological hallmarks of AD include beta-amyloid (Aβ) plaques, intracellular neurofibrillary tangles (NFTs), and chronic neuroinflammation, which can promote and exacerbate both …

Detection And Quantification Of Total Airborne Fungi And Coccidioides Species In Environmental Samples, Theresa T. Roehr

UNLV Theses, Dissertations, Professional Papers, and Capstones

Fungal exposure can cause acute and chronic illnesses or exacerbate existing illnesses. Some fungi are opportunistic pathogens and can lead to serious systemic fungal infections. In 2020, more than 150 million cases of severe fungal infections were reported globally resulting in an estimated 1.7 million deaths. Coccidioidomycosis, or Valley fever, is classified as a serious fungal infection caused by the fungi Coccidioides immitis and C. posadasii. These particular fungi are prevalent in the soil of the Southwestern United States, including Las Vegas, Nevada. In 2024, there were a total of 269 cases of Valley fever reported in Nevada, and …

Chronic Inflammation: The Link Between A High Added Sugar Diet And Disease, Anna Collins

Senior Honors Theses

The modern diet includes many processed foods that contain added sugars, resulting in a significant increase in daily glucose and fructose consumption. Considering this, there is an increased effort to uncover the effects of excess sugar intake on the body’s health and metabolism. Strong evidence supports the connection between a high added sugar diet and the presence of chronic, low-grade inflammation due to cellular distress and metabolic dysfunction. Prolonged inflammatory responses are linked to tissue damage and the development of various metabolic diseases that are prevalent in modern society, such as obesity, fatty liver disease, cardiovascular disease, and type 2 …

Phosphomimetic Substitution Of Serine Residue Ser260 With Aspartate Suggests Regulation Of Activity Of Human Cytosolic Malate Dehydrogenase By Phosphorylation, Charles Pelagalli '25, Luke Tischio, Kathleen Cornely

Chemistry & Biochemistry Faculty Publications

Human cytosolic malate dehydrogenase (MDH1) is a key enzyme involved in the malate-aspartate shuttle of eukaryotic cells, and which catalyzes the reaction of oxaloacetate to malate. As MDH1 is responsible for maintaining redox homeostasis by regeneration of NAD+ for glycolysis, its regulation is of particular interest in pharmaceutical applications, specifically in treating cancer cells that proliferate quickly and hence rely greatly on glycolysis. While the regulation of MDH1 by the phosphorylation of key residues has been previously documented, work still remains in identifying the specific residues involved in regulation of the enzyme by phosphorylation. In this study, we used …