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Investigation Of Genomic Instability Induced By G-Quadruplexes In The Absence Of Functional Topoisomerase 1 In Yeast, Alexandra Berroyer 2022 The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences

Investigation Of Genomic Instability Induced By G-Quadruplexes In The Absence Of Functional Topoisomerase 1 In Yeast, Alexandra Berroyer

The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences Dissertations and Theses (Open Access)

Topoisomerase 1 (Top1) is an enzyme that removes transcriptionally generated negative supercoils by binding and nicking DNA. Since transcription of guanine-rich DNA leads to the formation of G-quadruplex (G4) structures, Top1’s function likely suppresses G4-formation. In support of this, Top1 significantly reduces co-transcriptional G4 DNA-associated genomic instability at a model G4-motif in Saccharomyces cerevisiae. However, whether Top1 suppresses G4-formation on a genome-wide scale in yeast remains unexplored. Therefore, I aimed to uncover if deletion of Top1 enhances genome-wide G4-formation in S. cerevisiae. As an approach to quantify global G4-formation, I expressed the G4-specific antibody BG4 from a yeast …


The Role Of Stm1987 And Arti In Arginine Response Of Salmonella Typhimurium, Deeba Mohseni 2022 East Tennessee State University

The Role Of Stm1987 And Arti In Arginine Response Of Salmonella Typhimurium, Deeba Mohseni

Undergraduate Honors Theses

Cyclic-di-GMP, a common bacterial second messenger, has been thought to help develop virulence and biofilms in bacteria, most specifically in Salmonella Typhimurium. By being able to dysregulate cyclic-di-GMP production, virulence may be better combatted. STM1987, an L-arginine-responsive diguanylate cyclase with a periplasmic sensory domain, dimerizes and generates the bacterial second messenger cyclic-di-GMP in response to the amino acid L-arginine in a pathway that also requires the periplasmic L-arginine-binding protein ArtI. Their biochemical responses to L-arginine and when they dimerize could help clarify this pathway, so I sought to develop a periplasmic dimerization sensor to better monitor these biochemical interactions. Similar …


Alterations Of The Gut Mycobiome In Patients With Ms - A Bioinformatic Approach, Saumya Shah 2022 University of Connecticut

Alterations Of The Gut Mycobiome In Patients With Ms - A Bioinformatic Approach, Saumya Shah

Honors Scholar Theses

The mycobiome is the fungal component of the gut microbiome and is implicated in several autoimmune diseases. However, its role in multiple sclerosis (MS) has not been studied. We performed descriptive and formal statistical tests using the R language to characterize the gut mycobiome in people with MS (pwMS) and healthy controls. We found that the microbiome composition of multiple sclerosis patients is different from healthy people. The mycobiome had significantly higher alpha diversity and inter-subject variation in pwMS than controls. Additionally, Saccharomyces and Aspergillus were over-represented in pwMS. Different mycobiome profiles, defined as mycotypes, were associated with different bacterial …


Nitrogen Availability In Dune Systems And Its Effect On Root Fungal Endophyte Communities., Haley E. Sage 2022 University of Louisville

Nitrogen Availability In Dune Systems And Its Effect On Root Fungal Endophyte Communities., Haley E. Sage

College of Arts & Sciences Senior Honors Theses

As global change persists, changes in resource availability can influence plant-microbe interactions. To understand how resource availability can influence these interactions and species diversity, I focused this research on how varying nitrogen (N) levels affect root endophyte communities in the plant species Ammophila breviligulata, an ecosystem engineer in the dune system. I analyzed the relationship between nitrogen addition and microbial community composition across 60 plots treated with three nitrogen addition levels (control, low, and high) in a long-term experimental field site in the Lake Michigan dunes. I identified Ammophila breviligulata's root endophyte community after creating a culture collection and …


Functional Characterization Of A Putative Alternative Oxidase In Sporisorium Reilianum F. Sp. Zeae., Emma A Lamb 2022 University of Louisville

Functional Characterization Of A Putative Alternative Oxidase In Sporisorium Reilianum F. Sp. Zeae., Emma A Lamb

College of Arts & Sciences Senior Honors Theses

Sporisorium reilianum is a pathogenic basidiomycete fungus with two formae speciales, each capable of infecting corn (SRZ) or sorghum (SRS), respectively. This fungus is also a dimorphic variety, meaning it can switch between its haploid, yeast-like sporidia and diploid teliospore stages over the course of its life cycle (Schirawski). When S. reilianum is found in a haploid state and conditions are favorable, it will mate with a compatible non-self mating type to begin filamentous growth and proliferation in the plant host (Zhao). S. relianum, like most fungi, utilizes the four classical components of the electron transport chain to produce …


Bacteriophages: Paving The Road For The Future Of Medicine, Luke Brinkerhoff 2022 Ouachita Baptist University

Bacteriophages: Paving The Road For The Future Of Medicine, Luke Brinkerhoff

Honors Theses

Bacteriophages are a possible solution to antibiotic resistance, which is predicted to be detrimental world-wide by the year 2050. Personal field research was also conducted for a project studying the characteristics of two bacteriophages on a single bacterial host.


Using A Machine Learning Model To Predict Plant Inflorescences Based Upon Its Soil Microbiome, Luke Denoncourt 2022 William & Mary

Using A Machine Learning Model To Predict Plant Inflorescences Based Upon Its Soil Microbiome, Luke Denoncourt

Undergraduate Honors Theses

The UN estimates that the global population could reach 9.7 billion by 2050 (United Nations). As a result, the amount of food required to feed humanity is thought to double by 2050 (Ray et al., 2012). Humanity must find a way to increase crop production without increasing fertilizer usage and eutrophication, which can be done using the soil microbiome. Using potted plants with soils inoculated with Pseudomonas alcaligenes, Pseudomonas denitrificans, Bacillus polymyxa, and Mycobacterium phlei, both the shoot and root growth of pea and cotton plants was significantly increased (Egamberdieva & Höflich, 2004). In this study, utilizing a random forest …


Lysosomal Evasion Of Legionella Pneumophilia The Effector., Bethany Vaughn 2022 University of Louisville

Lysosomal Evasion Of Legionella Pneumophilia The Effector., Bethany Vaughn

Electronic Theses and Dissertations

Legionella pneumophila is a Gram-negative facultative intracellular bacterium found in freshwater environments that has co-evolved to survive and proliferate in various amoeba and protozoan species, which serve as the natural host for the bacterium. Humans are an accidental host of L. pneumophila, where infection occurs upon inhalation of aerosolized water droplets that contain the bacteria. Intracellular proliferation of L. pneumophila in alveolar macrophages is essential for manifestation of pneumonia, designated as Legionnaires’ Disease. Biogenesis of the legionella containing vacuole (LCV) occurs via interception of ER-Golgi vesicle trafficking and avoids the default endosomal/lysosomal degradation pathway. Intracellular proliferation of L. pneumophila …


Native And Non-Native Ant Impacts On Soil Microbes, Hannah A. Stewart 2022 State University of New York College at Buffalo - Buffalo State College

Native And Non-Native Ant Impacts On Soil Microbes, Hannah A. Stewart

Biology Theses

Organisms produce chemical weapons for defense, but target organisms can develop resistance. In their introduced range, non-native species may bring “novel weapons” against which native organisms have not co-evolved resistance. The invasive European fire ant (Myrmica rubra) may have brought antimicrobial secretions to the Northeastern United States that are novel weapons against native fungal and bacterial soil organisms. I hypothesized that M. rubra would better inhibit seed pathogens resulting in greater emergence of native myrmecochorous Viola sororia seeds and, as a side effect, more strongly inhibit arbuscular mycorrhizal fungi than a native seed dispersing ant (Aphaenogaster picea …


Neutrophil Subtype Differentiation In Campylobacter Jejuni Infection And Its Impact On T Cells And Colonic Epithelial Cells, Carolina Dolislager 2022 University of Tennessee, Knoxville

Neutrophil Subtype Differentiation In Campylobacter Jejuni Infection And Its Impact On T Cells And Colonic Epithelial Cells, Carolina Dolislager

Masters Theses

The discovery of neutrophil subtypes has expanded what is known about neutrophil functions, yet there is still much to learn about the role of these subtypes during bacterial infection. We investigated whether Campylobacter jejuniinduced differentiation of human neutrophils into the hypersegmented, CD16hi/CD62Llo[CD16hi/CD62Llo] subtype. In addition, we investigated whether C. jejuni-dependent differentiation of this neutrophil subtype induced cancer promoting activities ofhuman T cells and colonocytes, whichwere observed in other studies of hypersegmented, CD16hi/CD62Llo[CD16hi/CD62Llo] neutrophils. We found that C. jejunicauses a significant shift in human neutrophil populations to the hypersegmented, CD16 …


Ecological Controls On Successional Patterns In Bloom-Forming Cyanobacteria, Kyla L. Hooker 2022 University of Tennessee, Knoxville

Ecological Controls On Successional Patterns In Bloom-Forming Cyanobacteria, Kyla L. Hooker

Masters Theses

Harmful algal blooms are widespread in lake ecosystems but the ecological factors underlying their formation and maintenance are poorly understood. We revisit classical ecological theories which characterize and evaluate contrasting bottom-up and top-down influences on the selection of phytoplankton groups, such as Microcystis aeruginosa. We begin with a data compilation and analysis of environmental data from Lake Erie. This data analysis of nutrient concentrations, pigment concentrations, and zooplankton biomasses helps us understand and interpret what is happening in the environment throughout the year. Thus, allowing us to build a mathematical model to test our hypothesis. Our mathematical model asses …


Mathematical Modeling Of Potassium Modulated Viral Infection, Zaira Elizabeth Mather 2022 The University of Texas at El Paso

Mathematical Modeling Of Potassium Modulated Viral Infection, Zaira Elizabeth Mather

Open Access Theses & Dissertations

In recent years, there is a growing interest in the investigation of using potassium to treat virus infections. In the region of infection, there is a biological observation of extracel- lular potassium level being typically very low whereas the intracellular potassium levels are much higher. There are numerous biological studies showing that elevated potassium levels in the extracellular membrane tends to block virus infections. A recent effort in this direction is a collaborative research conducted by mathematicians and biologists from the University of Texas at El Paso, New Mexico State University, and the University of New Mexico, where we develop …


Elevated Levels Of External Cysteine Inhibit Nitrogen Fixation By The Methanogenic Archaeon Methanosarcina Acetivorans, Regan Massey 2022 University of Arkansas, Fayetteville

Elevated Levels Of External Cysteine Inhibit Nitrogen Fixation By The Methanogenic Archaeon Methanosarcina Acetivorans, Regan Massey

Biological Sciences Undergraduate Honors Theses

Methanogens are nitrogen fixing and methane producing archaea that play a key role in the cycling of carbon and nitrogen on earth. The global carbon and nitrogen cycle is vital to all life which makes the methanogen a primary organism of study. Methanogens are the only archaea capable of fixing nitrogen, and in order to do so, methanogens use a vital enzyme called the nitrogenase which fixes dinitrogen (N2) to ammonia (NH3). Expanding our understanding on metabolic processes of methanogens allows us to understand their environmental impact and advance their use in biotechnological applications. Methanosarcina acetivorans is the model used …


Temporal And Spatial Comparison Of Pseudo-Nitzschia Species Composition And Domoic Acid In Narragansett Bay, Rhode Island And The Northeast U.S. Shelf, Isabella Church, Bethany D. Jenkins 2022 University of Rhode Island

Temporal And Spatial Comparison Of Pseudo-Nitzschia Species Composition And Domoic Acid In Narragansett Bay, Rhode Island And The Northeast U.S. Shelf, Isabella Church, Bethany D. Jenkins

Senior Honors Projects

Diatoms are unicellular algae that make up a significant portion of phytoplankton biomass at the base of marine food webs. Narragansett Bay (NB), RI is home to several species of the diatom genus Pseudo-nitzschia (P-n), some of which are known to cause harmful algal blooms through the production of the potent neurotoxin domoic acid (DA). This toxin can lead to Amnesic Shellfish Poisoning in humans through the consumption of affected shellfish. Although the presence of P-n has been well established in NB for over 50 years, DA levels have only recently become a problem, with shellfish harvest closures …


Describing The Effect Of Thin Layer Sediment Placement On Coastal Microbial Communities Using Foraminifera Diversity, Elizabeth B. Billings 2022 University of Rhode Island

Describing The Effect Of Thin Layer Sediment Placement On Coastal Microbial Communities Using Foraminifera Diversity, Elizabeth B. Billings

Senior Honors Projects

Salt marshes are rich ecosystems that play an important role in aquatic food systems and prevent erosion while also providing essential habitats for wildlife. Climate change has resulted in rising sea levels and erosion of these coastal wetlands. Thin Layer Sediment Placement (TLP) is a restoration effort being implemented to mitigate the effects of climate change on coastal ecosystems. The TLP process raises elevation of the marsh and provides substrates for vegetative growth by spraying dredged sediment over existing marsh. The impacts of TLP on microbial populations is not widely understood, therefore metrics are required to study the effects of …


Identification Of Critical Points For Bacterial Contamination In The Microbrewery Environment, Alex Ryan Thompson 2022 Clemson University

Identification Of Critical Points For Bacterial Contamination In The Microbrewery Environment, Alex Ryan Thompson

All Theses

There are 8,884 craft breweries producing over 23 million barrels of beer in the United States as of 2020. These 23 million barrels of craft beer account for 12.3% of the United States beer consumption in 2020. The American craft beer industry is substantial and needs to protect its product from bacterial contamination.

Overall, beer is a microbially stable product. Beers pH, ethanol levels, CO2 concentrations, the presence of hop-derived antimicrobial compounds, and low levels of O2 make beer a highly unfavorable environment for most bacterial species. Furthermore, the brewing process, which involves heat treatments and chemical sanitizers …


Mechanistic Insights On The Role Of Ambrisentan, An Endothelin Type-A Receptor Antagonist, In Breast Cancer, Ruba Saleem Lutfi Amer 2022 United Arab Emirates University

Mechanistic Insights On The Role Of Ambrisentan, An Endothelin Type-A Receptor Antagonist, In Breast Cancer, Ruba Saleem Lutfi Amer

Theses

The activation of the endothelin receptor type A (ETAR) by its ligand endothelin-1 (ET-1) is well known for its role in vasoconstriction. Interestingly, ET-1 and ETAR are over-expressed in various human tumours, including breast cancer. Several studies described the important role of ETAR in cancer progression and metastasis. The extensive network of interactions that exist between the ET-1 axis and other signalling pathways can trigger autocrine and paracrine signalling that modulates different tumorigenesis processes, such as cellular proliferation and survival, epithelial-to-mesenchymal transition (EMT) and chemoresistance. The main objective of this study was to investigate the antitumor effects of Ambrisentan, a …


Genomic Analysis Of Metabolic Differences Found In Clostridium Perfringens That Cause Necrotic Enteritis In Poultry, Connor Aylor 2022 University of Nebraska-Lincoln

Genomic Analysis Of Metabolic Differences Found In Clostridium Perfringens That Cause Necrotic Enteritis In Poultry, Connor Aylor

Dissertations & Theses in Veterinary and Biomedical Science

Clostridium perfringens is a common member of gut microbiota in healthy animals, but can also be an important pathogen in human and veterinary medicine. It produces several protein toxins that contribute to both histotoxic and enteric diseases in animals. Necrotic enteritis in poultry has been associated with the NetB toxin of C. perfringens; however, this toxin alone is insufficient to cause disease in infected chickens. While considerable research has focused on the presence of toxins and virulence factors, little has been done to assess the function of metabolic factors on the ability of the bacteria to cause disease. In …


Literature Review: Antibody Production In Mice In Response To Aspergillus Fumigatus Inhalation, Jenica Hancock, Courtney Folk 2022 Minnesota State University Moorhead

Literature Review: Antibody Production In Mice In Response To Aspergillus Fumigatus Inhalation, Jenica Hancock, Courtney Folk

Student Academic Conference

Aspergillus fumigatus is a commonly inhaled respiratory fungal pathogen and an allergen found in flooded indoor environments, household dust, soil, and plant matter. Inhalation of A. fumigatus poses a threat to weakened immune systems due to the potential of infection in the lungs or sinuses which can spread to other areas of the body. The mouse genome is 99% similar to the human genome, and therefore they serve effectively in modeling the effects of inhaled A. fumigatus. A comprehensive literature search of antibody production in mice in response to A. fumigatus inhalation was conducted utilizing PubMed and the search terms …


Diversity Of Bacteriophage In Burkholderia Species, Abigail Price 2022 Bowling Green State University

Diversity Of Bacteriophage In Burkholderia Species, Abigail Price

Honors Projects

Bacteriophages are viruses that infect and replicate within bacteria and offer the potential of a therapeutic alternative to chronic infections that do not respond to antibiotic-based therapies. B. vietnamiensis is one of a number of Burkholderia species involved with chronic drug resistant infections in the lungs of individuals with compromised respiratory systems, as found in those with chronic obstructive pulmonary disease and, most especially, are of particular significance in patients with cystic fibrosis. The diversity of the Burkholderia species is explored by using online databases and looking at bacteriophage or phage-encoding viruses found in B. vietnamiensis. The open reading frames …


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