Biochemistry, Biophysics, and Structural Biology Commons^™

Characterization Of P43lgrn-3, Kelly G. Hill

Honors Theses

Alzheimer’s Disease (AD) is a progressive neurodegenerative disorder characterized by extensive memory loss and cognitive deficits, which occur due to severe neuronal loss. Two hallmark lesions, intracellular neurofibrillary tangles composed of hyperphosphorylated tau and extracellular neuritic plaques formed by the aggregation of amyloid-β (Aβ), are responsible for the progressive neuronal loss seen in AD brains. Neurotoxic Aβ aggregates are also known to cause inflammation within the brain. It has recently come to light that severe and acute inflammation, such as seen in traumatic brain injury (TBI), may also lead to AD-type dementia. This has raised the question whether some of …

The Preparation Of Synthetic Myod Mrna For Cellular Differentiation And Innate Immune Response Downstream Application, James D. Grenn

Honors Theses

The development of therapeutic immune responses from the manipulation of embryonic stem cells (ESCs) via induction of synthetic RNA with 5’ capped and 3’ poly(A)tailed ends would lead to development of stem cell therapy. A necessary step in attaining such a goal is to first produce an mRNA transcript from a plasmid containing the open reading frame (ORF) for a transcription factor for cellular activation.

In this research, the DNA plasmid pMD4 encoding MyoD was transcribed into synthetic mRNA. The plasmid was first amplified using Polymerase Chain Reaction (PCR), and analyzed using gel electrophoresis. The amplified template was purified via …

Altering The Structure Of Carboxysomal Carbonic Anhydrase Csosca To Determine The Necessity Of The N-Terminal Domain In Csosca Function, Dana L. Dillistone

Honors Theses

In this project, a DNA construct was designed and developed to remove the first fifty amino acids of the CsoSCA protein in the chemolithotrophic bacterium Halothiobacillus neapolitanus. The csoS3 gene codes for a carbonic anhydrase enzyme (CsoSCA) that is unique to a structure called a carboxysome. Carboxysomes are polyhedral microcompartments where carbon fixation is housed. The carbonic anhydrase is a shell-associated protein that improves the catalytic efficiency of ribulose-bisphosphate carboxylase/oxygenase (RuBisCO), the enzyme that catalyzes the fixation of carbon. By deleting the first fifty amino acids of the carbonic anhydrase, the necessity of the amino acids in carboxysome function was …

Elucidating The Interplay Between Sodium Selenite On The Tick Amblyomma Maculatum Selenoprotein Gene Expression, Afnan M. Beauti

Honors Theses

Selenium (Se) is an element recognized as an essential micronutrient in eukaryote organisms. Selenoproteins contain selenium as selenocysteine, the 21st amino acid. Selenium plays a role in cell growth and functioning. At low concentrations, it can induce growth and at high concentrations, it can cause a cell to stop growing and potentially have toxic effects on the cell and organism. When selenium levels are high, oxidative stress results by the production of reactive oxidative species. Selenoproteins, however, can aid the antioxidant response in the cell. Ticks are arthropods of interest, as they are one of few that contain many selenogenes, …

Phopsphorylation And Ubiquitin Modification At Dna Damage Sites In Response To Double-Strand Breaks, Atanu Paul

Dissertations and Theses (Open Access)

Genomes of all organisms are continuously damaged by numerous exogenous and endogenous sources leading to different kinds of DNA lesions, which if not repaired efficiently may trigger wide-scale genomic instability, a hallmark of cancer development. To overcome this, cells have evolved a sophisticated sensory network called the DNA damage response (DDR) comprised of a large number of distinct protein complexes categorized as sensor, mediator, transducer and effector proteins that amplify the DNA damage signal and activate cell cycle checkpoint to initiate DNA repair or trigger apoptosis where the defect is beyond repair. This intricate signaling pathway is tightly regulated by …

Role Of Mir-29b-1 And Mir-29a In Endocrine-Resistant Breast Cancer., Penn Muluhngwi

Electronic Theses and Dissertations

Therapies targeting estrogen receptor α (ERα) including selective estrogen receptor modulators (SERMs), e.g., tamoxifen (TAM); selective estrogen receptor downregulators (SERDs), e.g., fulvestrant (ICI 182,780); and aromatase inhibitors (AI), e.g., letrozole, are successfully used in treating breast cancer patients whose initial tumor expresses ERα. Unfortunately, the effectiveness of endocrine therapies is limited as ~ 40% of breast cancer patients will eventually acquire resistance to them. The role of miRNAs in the progression of endocrine-resistant breast cancer is of keen interest in developing biomarkers and therapies to counter metastatic disease. This dissertation begins with a review on miRNAs implicated …

Genetically Encoded Fluorescent Protein Biosensor For Nitric Oxide, Wenjia Zhai

Department of Chemistry: Dissertations, Theses, and Student Research

Nitric oxide (NO) is an important molecule in living cells for signaling, thus a specific sensor to detect its level in live cells is needed. Currently there are a few small molecule probes for the detection of NO. A common shortcoming of these probes is their unavoidable leakage from the target cells. In this project, I seek to develop a novel green fluorescent protein (GFP)-based biosensor to detect cellular NO. This GFP-based sensor is genetically encodable and can potentially avoid the possible false positive result due to the leakage. I synthesized an unnatural amino acid (unAA) and examined its incorporation …

Disorder In Cysteine-Rich Granulin-3 And Its Implication In Alzheimer Disease, Gaurav Ghag

Dissertations

Granulins (GRNs) are a family of small, cysteine-rich proteins that are generated upon proteolytic cleavage of their precursor, progranulin (PGRN) during inflammation. All seven GRNs (1 – 7 or A – G) contain twelve conserved cysteines that form six intramolecular disulfide bonds, rendering this family of proteins unique. GRNs play multiple roles and are involved in a myriad of physiological as well as pathological processes. They are known to a play role in growth and embryonic development, wound healing, and signaling cascades as well as in tumorigenesis. They are also implicated in neurodegenerative diseases like frontotemporal dementia (FTD), Alzheimer disease …

Role And Regulation Of Sphingosine 1-Phosphate In Erythrocyte, Kaiqi Sun

Dissertations and Theses (Open Access)

Sphingosine 1-phosphate (S1P) is a bioactive signaling sphingolipid produced in every mammalian cell. It plays a variety of important roles both in and outside of cells. S1P is highly enriched in mature erythrocytes because of the high enzymatic activity of the S1P-generating enzyme Sphingosine Kinase 1 (Sphk1) and the absence of S1P degrading enzymes. Erythrocytes are considered only a major reservoir for S1P because they supply S1P to the circulation for the regulation of various physiological processes which include but are not limited to immune cell trafficking, endothelial integrity and hematopoietic stem cell mobilization. However, if S1P plays a role …

Fret-Based Investigations Of The Structure-Function Relationships In The Nmda Receptor, Drew M. Dolino

Dissertations and Theses (Open Access)

The N-methyl-D-aspartate (NMDA) receptor is one member of a class of proteins known as the ionotropic glutamate receptors. Ionotropic glutamate receptors mediate the majority of excitatory neurotransmission in the central nervous system, with the NMDA receptor standing out among these receptors for its requirement of a co-agonist, its magnesium-block-based coincidence detection, its slow kinetics, its calcium permeability, its allosteric modulation, and its especially important functional roles in synaptic plasticity, excitotoxicity, and more. In recent years, a wealth of structural information has come about describing endpoint structures to high resolution, but such structures are unable to fully resolve the movements …

Analysis Of The Biochemical And Cellular Activities Of Substrate Binding By The Molecular Chaperone Hsp110/Sse1, Veronica M. Garcia

Dissertations and Theses (Open Access)

Molecular chaperones ensure protein quality during protein synthesis, delivery, damage repair, and degradation. The ubiquitous and highly conserved molecular chaperone 70-kDa heat-shock proteins (Hsp70s) are essential in maintaining protein homeostasis by cycling through high and low affinity binding of unfolded protein clients to facilitate folding. The Hsp110 class of chaperones are divergent relatives of Hsp70 that are extremely effective in preventing protein aggregation but lack the hallmark folding activity seen in Hsp70s. Hsp110s serve as Hsp70 nucleotide exchange factors (NEF) that facilitate the Hsp70 folding cycle by inducing release of protein substrate from Hsp70, thus recycling the chaperone for a …

The Role Of Adenosine Signaling In Mature Erythrocytes And Erythroid Progenitors, Hong Liu

Dissertations and Theses (Open Access)

Adenosine is a ubiquitous nucleoside in almost all the cells throughout our bodies. It is highly induced particularly under hypoxia or energy depletion conditions. Adenosine functions as a critical ligand, after binding to membrane-associated adenosine receptors, adenosine initiates a downstream signaling cascade and subsequently contributes to functions of nervous system, immune response, vascular function and even metabolism.

Hypoxia is a condition with limited O₂ availability in the whole body or a region of the body. It is a major consequence of many respiratory and cardiovascular diseases, as well as for people living and working at high altitudes or other …

Understanding The Mechanism Of Genomic Instability During Replicative Aging In Budding Yeast, Sangita Pal

Dissertations and Theses (Open Access)

Aging brings a gradual decline in molecular fidelity and biological functionality, resulting in age related phenotypes and diseases. Despite continued efforts to uncover the conserved aging pathways among eukaryotes, exact molecular causes of aging are still poorly understood. One of the most important hallmarks of aging is increased genomic instability. However, there remains much ambiguity as to the cause. I am studying the replicative life span (RLS) of the genetically tractable model organism Saccharomyces cerevisiae, or budding yeast using the innovative “mother enrichment program” as the method to isolate unparalleled numbers of aged yeast cells to investigate the molecular changes …

A Genetic Analysis Of Nuclear Functions Of The Lipin Protein In Drosophila Melanogaster, Xeniya Rudolf

Graduate Theses and Dissertations

Lipins are a family of proteins that have critical functions in the control of fat storage and energy homeostasis. Biochemically, lipins have two functions. They provide an enzymatic activity (phosphatidate phosphatase or PAP activity) in the glycerol-3 phosphate pathway that leads to the production of storage fats (triacylglycerols). In addition, they play a role in the regulation of genes in the cell nucleus as transcriptional co-regulators. The PAP activity of lipins has been widely studied in a number of organisms. However, the transcriptional co-regulator function is not as well described in the literature. The transcriptional function of lipins depends on …

Enzyme Kinetics Studies To Guide Mathematical Modeling Of Microdialysis Sampling To Predict In Situ Biochemistry, Justin M. Klucher

Chemistry & Biochemistry Undergraduate Honors Theses

Microdialysis is a diffusion-based sampling method that can be useful for monitoring various biological systems. Matrix metalloproteinases are a class of enzymes responsible for remodeling the extracellular matrix that, when dysregulated, are linked to various diseases. The delivery method of microdialysis is of particular interest as a sampling technique for enzymatic reactions. Microdialysis was performed in vitro using a model enzyme, porcine pancreatic elastase, because it is a useful substitute for matrix metalloproteinases. A colorimetric substrate for elastase, succinyl-ala-ala-ala-p-nitroanilide, and its product p-nitroaniline were measured using a UV-Vis spectrophotometer. Using an expanded Beer’s Law equation, both analytes’ concentrations were determined …

First-Row Transition Metal Sulfides And Phosphides As Competent Electrocatalysts For Water Splitting, Nan Jiang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Solar energy is a carbon-neutral and renewable energy resource. Its nature of intermittence and unequal distribution requires efficient solar energy capture, conversion, and storage. Solar-driven water splitting to produce hydrogen and oxygen is widely considered as an appealing approach to meet this goal, in which hydrogen acts as a green energy carrier. Water splitting consists of two redox half reactions: hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Both reactions involve the transfer of multiple electrons and protons and possess high energy barriers to proceed at appreciable rates, hence catalysts are needed.

A large number of HER and OER …

Conservative Tryptophan Mutations In Protein Tyrosine Phosphatase Ptp1b And Its Effect On Catalytic Rate And Chemical Reaction, Teisha Richan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Protein-tyrosine phosphatases (PTPs) catalyze the hydrolysis of phosphorylated tyrosines by a 2-step mechanism involving nucleophilic attack by cysteine and general acid catalysis by aspartic acid. In most PTPs the aspartic acid resides on a flexible protein loop, consisting of about a dozen residues, called the WPD loop. PTP catalysis rates span several orders of magnitude, and differences in WPD loop dynamics have recently been show to correlate with the rate of enzymatic catalysis. The rate of WPD loop motion could possibly be related to a widely conserved tryptophan residue on the WPD loop. Therefore, point mutants were made in PTP1B …

Mechanism Of Substrate Reduction By Nitrogenase, Nimesh Khadka

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nitrogen (N) is a vital element of life and the main component of chemical fertilizer. The industrial Haber-Bosch process fulfills the demands of today’s nitrogen need and is therefore considered as one of the major scientific breakthroughs of the last century. However, the Haber-Bosch process operates at very high temperature and pressure, and requires fossils fuels to drive the reaction, making it an energy expensive process. The energy demand for this process accounts for almost 3% of the total global energy consumption. In addition, the rapid population growth, economic development and depletion of limited non-renewable fossil fuels have already created …

Influence Of Histidine Residues, Ph And Charge Interactions On Membrane-Spanning Peptides, Ashley N. Henderson

Graduate Theses and Dissertations

Designed transmembrane peptides were employed for investigations of histidine residues within the hydrophobic environment of the lipid bilayer by means of oriented solid-state deuterium NMR spectroscopy. Using the model peptide GWALP23 sequence (GGALW(LA)6LWLAGA) as a host framework, the effects of single and double histidine mutations were explored. Replacement of leucine residue 12 to polar neutral histidine had little influence on the peptide average orientation, however under strongly acidic pH conditions in DOPC bilayers, the histidine becomes positively charged (pKa 2.5) and the GWALP23-H12 peptide exits the membrane and adopts a surface-bound orientation. Conversely, mutation of leucine 14 to neutral histidine …

The Effect Of Galactose On The Expression Of Genes Regulated By Rrp6p, Mary Megan Pelkowski, Kevin Callahan

The Review: A Journal of Undergraduate Student Research

Gene expression is a multi-faceted phenomenon, governed not only by the sequence of nucleotides, but also by the extent to which a particular gene gets transcribed, how the transcript is processed, and whether or not the transcript ever makes it out of the nucleus. Rrp6p is a 5’-3’ exonuclease that can function independently and as part of the nuclear exosome in Saccharomyces cerevisiae (Portin, 2014). It degrades various types of aberrant RNA species including small nuclear RNAs, small nucleolar RNAs, telomerase RNA, unspliced RNAs, and RNAs that have not been properly packaged for export (Butler & Mitchell, 2010). This exosome …

Design Of A Robust Undergraduate Biochemistry Laboratory Course Based On A Modified And Expanded Bovine Serum Albumin Purification Scheme, Odutayo O. Odunuge, Nicholas Cheatwood, John Mullins, Michele Harris

Symposium on Arts and Research

The ASBMB curriculum for an undergraduate degree recommends a set of skills that can be acquired only through laboratory courses and research experience. Based on a previously reported purification scheme for BSA (Odunuga and Shazhko, 2013), we designed a robust, reproducible, cost-effective, safe and enquiry-based undergraduate biochemistry laboratory course that encompasses many of the skill-sets recommend-ed in the ASBMB curriculum. Our work not only modi-fied certain steps in the scheme, it also included addi-tional steps to enhance student learning and skill ac-quisition. Salt precipitation, ion exchange and size ex-clusion chromatography were employed by students to purify BSA from cow plasma. …

Relative Importance Of Black Carbon, Brown Carbon, And Absorption Enhancement From Clear Coatings In Biomass Burning Emissions, Rudra P. Pokhrel, Eric R. Beamesderfer, Nick L. Wagner, Justin M. Langridge, Daniel A. Lack, Thilina Jayarathne, Elizabeth A. Stone, Chelsea E. Stockwell, Robert J. Yokelson, Shane M. Murphy

Chemistry and Biochemistry Faculty Publications

A wide range of globally significant biomass fuels were burned during the fourth Fire Lab at Missoula Experiment (FLAME-4). A multi-channel photoacoustic absorption spectrometer (PAS) measured dry absorption at 405, 532, and 660 nm and thermally denuded (250 °C) absorption at 405 and 660 nm. Absorption coefficients were broken into contributions from black carbon (BC), brown carbon (BrC), and lensing following three different methodologies, with one extreme being a method that assumes the thermal denuder effectively removes organics and the other extreme being a method based on the assumption that black carbon (BC) has an Ångström exponent of unity. The …

Antimicrobial Properties Of S-Benzofuran-2-Yl Ethanol Produced By Biotransformation, Nick Cheatwood, Ann Davis, Elizabeth Schabeck, Kelsi Hooker, Michele Harris

Undergraduate Research Conference

All living organisms contain enzymes to carry out biological reactions, which produce substances with a specific three dimensional shape. Enantiomers are two molecules that are mirror images of each other just as hands are mirror images of each other. It is well known in the pharmaceutical world that one of the enantiomers (one of the mirrorimage molecules) has a positive biological effect while the other can be harmful or have no effect. Currently, any potential pharmaceutical that could exist as enantiomers must have each enantiomer tested for biological activity prior to FDA approval. In our laboratory, we have focused on …

Dna-Binding And Cellular Uptake Properties Of Pyrrole-Imidazole Polyamides, Maria J. Scuderi

Dissertations

Pyrrole-imidazole polyamides (PAs) represent a class of synthetic ligands that bind to the minor groove of DNA through hydrogen bonds and can be programmed to recognize predetermined DNA sequences. Potential applications of these compounds include gene expression modulation, antimicrobial activity and cell imaging.

Studies conducted in our lab in collaboration with NanoVir have shown that large PAs exhibit antiviral activity against Human Papillomavirus (HPV), which is the most common sexually transmitted infectious agent in the US and the primary factor for the development of cervical cancer. PAs act against HPV by targeting the viral DNA and promoting its selective elimination …

Physiological Effects Of Five Different Marine Natural Organic Matters (Noms) And Three Different Metals (Cu, Pb, Zn) On Early Life Stages Of The Blue Mussel (Mytilus Galloprovincialis), Lygia Sega Nogueira, Adalto Bianchini, Scott Smith, Marianna Basso Jorge, Rachael L. Diamond, Chris M. Wood

Chemistry Faculty Publications

Metals are present in aquatic environments as a result of natural and anthropogenic inputs, and may induce toxicity to organisms. One of the main factors that influence this toxicity in fresh water is natural organic matter (NOM) but all NOMs are not the same in this regard. In sea water, possible protection by marine NOMs is not well understood. Thus, our study isolated marine NOMs by solid-phase extraction from five different sites and characterized them by excitation-emission fluorescence analysis—one inshore (terrigenous origin), two offshore (autochthonous origin), and two intermediate in composition (indicative of a mixed origin). The physiological effects of …

Biophysical Studies Of Hairpin Polyamides With Broad-Spectrum Activity Against High-Risk Human Papillomaviruses, Carlos H. Castaneda

Dissertations

Human papillomavirus is a small dsDNA virus that infects mucosal and cutaneous epithelial tissues. Persistent infection with high-risk HPV is the main etiological agent in the development of cervical cancer worldwide. Although prophylactic vaccines against HPV are available, these preventative measures are type-specific and are ineffective against existing infections. Thus, there is a pressing need for antiviral drugs with a broad-spectrum activity against HPV to eradicate existing infections, no matter the subtype.

Our group and collaborators have synthesized an extensive library of novel N-methylpyrrole/N-methylimidazole (Py/Im) hairpin polyamides (PAs) with broad-spectrum activities against three prevalent oncogenic-HPV types (HPV16, …

Creation Of An Immunodeficient Hla-Transgenic Mouse (Humamice) And Functional Validation Of Human Immunity After Transfer Of Hla-Matched Human Cells, Yang Zeng, Bingrun Liu, Marie-Therese Rubio, Xinyue Wang, David M. Ojcius, Ruoping Tang, Antoine Durrbach, Zhitao Ru, Yusen Zhou, Yu-Chun Lone

All Dugoni School of Dentistry Faculty Articles

Research on human immunology has been hindered by the lack of optimal small animal models, given that the protective immune responses of human and non-human species show significant differences. However, due to ethical constraints[1] and the high cost of clinical trials, it is urgent to improve the current animal models that can mimic faithfully human physiology, particularly the human immune system (HIS). HIS mice had been generated recently by engrafting human hematopoietic stem cells (hHSCs) or human peripheral mononuclear cells (hPBMCs) into highly immuno-deficient mice such as NSG, NOG or NRG mice. However, a major experimental drawback for studies using …

Oxidation Of Substituted Catechols At The Air-Water Interface: Production Of Carboxylic Acids, Quinones, And Polyphenols, Elizabeth A. Pillar, Marcelo I. Guzman

Chemistry Faculty Publications

Anthropogenic activities contribute benzene, toluene, and anisole to the environment, which in the atmosphere are converted into the respective phenols, cresols, and methoxyphenols by fast gas-phase reaction with hydroxyl radicals (HO(•)). Further processing of the latter species by HO(•) decreases their vapor pressure as a second hydroxyl group is incorporated to accelerate their oxidative aging at interfaces and in aqueous particles. This work shows how catechol, pyrogallol, 3-methylcatechol, 4-methylcatechol, and 3-methoxycatechol (all proxies for oxygenated aromatics derived from benzene, toluene, and anisole) react at the air-water interface with increasing O3(g) during τc ≈ 1 μs contact time and contrasts their …

Testing Effectiveness Of Aqueous Phases From Struvite And Hydroxyapatite Mineral Precipitation As Algal Nutrient Sources, Aaron Lyons

Virginias Collegiate Honors Council Conference

As interest in algal biofuel grows, the need to explore diverse nutrient sources for growing algae becomes apparent. Struvite and Hydroxyapatite (HAP) were precipitated after flash hydrolysis. The leftover aqueous phase (AP) could serve as nutrients source for algae cultivation and the potential reuse of this waste stream is promising. To test this, 12 bottles of Scenedemus sp., four of Struvite, four of HAP, and four control AM-14 synthetic media were cultivated. 10% of the Phosphorus in the synthetic media was replaced with phosphorous from the struvite AP, and 10% of the nitrogen in the synthetic media was replaced …

Tracking The Sexual Assault Kit Backlog, Kallie Crawford, Lyndsie Ferrara

Undergraduate Research and Scholarship Symposium

The backlog of untested sexual assault kits is a national problem. Numerous federal funding opportunities offer the forensic science and law enforcement communities valuable resources needed to test the kits, but issues still remain. The majority of resources are focused on the collection and testing of sexual assault kits, but the tracking of the kits has not been a primary focus. This research highlights improvements that can be made to better understand the current backlog and improve the future processing and tracking of kits. Given the lack of a universal evidence tracking database among agencies, tracking sexual assault kits seems …