Microbiology Commons^™

Assessing The Role Of Daily Thermal Fluctuations In The Performance Of Mitochondrial Energy Transduction Of The Centrarchid, Lepomis Cyanellus, Grayson Hofmann

Masters Theses

Freshwater systems are affected by current climate extremes, forcing species found in these systems to withstand drastic changes in temperature. Temperature changes affect these organisms by altering their metabolic rate and energy balance. Increases in temperature can lead to an increase in oxygen consumption, which ultimately increases the need for more energy production. Mitochondrial energy transduction of green sunfish (Lepomis cyanellus) and many other fish species after a thermal insult, has hardly been explored. This study complements the limited research available on mitochondrial function in similar species, as they ignore the possibility of consecutive thermal events, which are …

Identification Of Host-Pathogen Protein Interactions: Yeast Two-Hybrid Analysis Of Sars-Cov-2 Nsp10 And Human Cellular Proteins, Antonios Argyriou

Selected Full-Text Master Theses 2021-

The ongoing COVID-19 pandemic, caused by SARS-CoV-2, has resulted in over 774 million cases and 7 million deaths worldwide, establishing it as one of the most devastating pandemics in recorded history. While current therapeutic approaches primarily target viral entry mechanisms and specific enzymes, the limited understanding of non-structural protein functions hinders the development of comprehensive antiviral strategies. This research focuses on Nsp10 (non-structural protein 10), a highly conserved 139-amino acid protein essential for viral mRNA capping and replication. Nsp10 serves as a critical cofactor in the formation of methyltransferase complexes with Nsp14 and Nsp16, playing a vital role in viral …

Brachial Plexus Lesions: Uncommon Causes And Clinical Sequelae, Lucy Greenhagen

Biology and Microbiology Graduate Students Plan B Research Projects

The brachial plexus is a complex network of nerves that transmit motor and sensory information between the spinal cord and upper extremities. Brachial plexus lesions may be caused by a broad range of congential and traumatic conditions. These lesions present a challenge to healthcare providers both for diagnosis and treatment. While variations in the brachial plexus have been widely reported, resources outlining the prevenance and involvement of anatomical variation along with their possible clinical presentation are more limited. The objective of this review is to describe uncommon causes of brachial plexus lesions and the clinical challenges they present for providers. …

Alternative Treatments And Potential Cures For Type 1 Diabetes, Dillon Peterson

Biology and Microbiology Graduate Students Plan B Research Projects

Type 1 diabetes (T1D) is an autoimmune disease that affects multitudes of people without a cost-effective cure. T1D is caused by the immune system reaching a threshold where it then begins to attack the beta cells in the pancreas causing inflammation, which eventually leads to the death of beta cells. Once a large majority of the beta cells die off, the pancreas begins to inadequately supply insulin to the body, which is when the symptoms of T1D begin to emerge. To treat these symptoms, the person must utilize synthetic insulin. The utilization of synthetic insulin, along with the plethora of …

A Novel Silver-Ruthenium-Based Antimicrobial Kills Gram-Negative Bacteria Through Oxidative Stress-Induced Macromolecular Damage, Patrick O. Tawiah

Theses and Dissertations

The rise in drug-resistant bacteria, together with the decline in antibiotic development, requires new strategies for infectious disease control. Gram-negative pathogens are particularly challenging to combat due to their outer membrane. This study highlights the effectiveness of the silver-containing antimicrobial AGXX® against the Gram-negative bacterium Escherichia coli. AGXX® is a promising silver coating that presumably kills bacteria through the generation of reactive oxygen species (ROS). However, neither AGXX®’s mode of action is fully understood, nor have its effects on Gram-negative bacteria or bacterial response and defense mechanisms towards AGXX® been studied in detail. Here, I report that the bactericidal …

Backyard Chimeric Microbiomes: K-12 Participatory Science, Abigail Saucier

Honors Theses and Capstones

The US education system has seen a recent push for more secondary school curriculum to include STEM (Science, Technology, Engineering, and Mathematics) materials and activities. Middle and high school is a pivotal time when academic and personal experiences affect the development of student attitudes towards STEM (Christensen et al., 2015; Moreno et al., 2016). Teachers often utilize hands-on activities to promote student engagement with science curriculum (Brooks & Poles, 2021; Christensen et al., 2015). Hands-on activities improve student learning, but impacts vary by type of activity. When students work towards a known outcome they can feel disconnected from the work …

The Influence Of Flower-Microbe Interactions On Bumble Bee Behavior And Gut Microbiome Composition, Success Chiamaka Ekemezie

Graduate Theses/Dissertations

This thesis examines how microbial interactions in floral nectar and environmental variation influence bumble bee (Bombus spp.) foraging behavior and gut microbiome composition. Pollen germination experiments and behavioral assays in the lab tested whether Metschnikowia reukaufii (yeast) and Acinetobacter nectaris (bacteria) induce pollen germination and bursting in nectar and affect bee behavior subsequently. Both microbes reduced intact pollen, but bees did not alter flower preference. Furthermore, the study also assessed how floral and bee community composition shaped gut microbiome composition across six Missouri prairies. Using amplicon-sequenced fungal ITS and bacterial 16S rRNA genes, I found that fungal microbiome composition varied …

Inoculating Soybean Plants At Different Growth Stages: Selecting Bradyrhizobium, Sinorhizobium, Or Both, Matthew R. Knoll

Graduate Theses/Dissertations

Soybean plants rely on nitrogen for growth, however atmospheric nitrogen (N2) is not a usable form and needs to be converted into different forms that are available to the plant. Nitrogen fixing bacteria such as rhizobia form symbiotic relationships with Soybeans in exchange for shelter and excess plant sugars. As a result, the plant can get the nitrogen it needs. There are four main genera of rhizobia that can form root nodules on Soybean including Bradyrhizobium, Sinorhizobium, Mesorhizobium, and Rhizobium. At this point, the effect that age of the host plant has on the selection of …

Biotransformation Of Camelina Meal Via Pretreatment And Fermentation For Functional And Nutritional Upgrading, Ram Kumar Bhattarai

Electronic Theses and Dissertations

Camelina sativa, an oilseed crop of the Brassicaceae family, has seen increased cultivation in North America in response to the rising demand for biofuels over the past two decades. With this growth, camelina meal, a byproduct of oil extraction, has emerged as a promising yet underutilized resource, particularly for applications in animal nutrition. This study aimed to evaluate the potential of camelina meal as a substrate for submerged fungal fermentation and to examine how this bioconversion affects its physicochemical and nutritional properties. The influence of mild pretreatments (unwashed, washed only, and washed/dried and ground) on fermentation outcomes was also assessed. …

Analyzing Microbial Communities In Porites Astreoides, Sanaa Caldwell, Katie Parker, Daniel Barshis

Biological Sciences Faculty Publications

Coral reefs are vital marine ecosystems that support many different species and ecosystem services through protecting coastlines from storms and erosion, providing raw materials for medication, and facilitating diversity amongst marine species. Anthropogenic climate change is causing ocean temperatures to exceed the range of coral thermal tolerance resulting in more coral bleaching events globally. However, some corals have the capacity to withstand high temperatures through different thermal tolerance strategies. A balanced microbial community plays a critical role in coral health and recent studies have indicated that a balanced microbiome is associated with temperature-stress tolerant corals. Yet, there is a severe …

Impacts Of Tick Parasitism On The Rodent Gut Microbiome, Robert J. Brinkerhoff, Joshua Pandian, Meghan Leber, Isabella D. Hauser, Holly D. Gaff

Biological Sciences Faculty Publications

Host microbiota may impact disease vector behavior and pathogen transmission, but little is known about associations between ectoparasites and microbial communities in wildlife reservoir species. We used Illumina metagenomic sequencing to explore the impacts of tick parasitism on the rodent fecal microbiome in both a field and laboratory setting. We found that tick parasitism on wild hosts was associated with variation in the fecal microbiota of both the white-footed deermouse, Peromyscus leucopus, and the southern cotton rat, Sigmodon hispidus. In a lab experiment, we detected significant changes to the fecal microbiome after experimental exposure to immature ticks in …

The Role Of Fruiting Bodies In Protecting A Community Of Myxococcus Xanthus Spores From The Environment, Dave Lall

Wayne State University Dissertations

Environmental microorganisms have evolved a variety of strategies to survive fluctuations in environmental conditions, including the production of biofilms and differentiation into spores. Myxococcus xanthus are ubiquitous soil bacteria that produce starvation-induced multicellular fruiting bodies filled with environmentally resistant spores (a specialized biofilm). Isolated spores have been shown to be more resistant than vegetative cells to heat, ultraviolet radiation, and desiccation. The evolutionary advantage of producing spores inside of fruiting bodies is not clear. Here, we examine a hypothesis that the fruiting body provides additional protection from environmental insults. We developed a high-throughput method to compare the recovery (outgrowth) of …

The Chemical Ecology Of A Caribbean Boulder Coral During Restoration And The Interplay Between Fish Predation And Microbiome Variation, Catherine E. Raker

Open Access Dissertations

Coral reefs are one of the most biodiverse and productive ecosystems on the planet. In recent decades, however, climate change and other global threats have caused severe declines in live coral cover worldwide. Coral propagation, or “gardening,” is a popular strategy to attempt to restore healthy corals to degraded reefs. Slow-growing boulder corals are often restored using microfragmentation, where cutting coral colonies into roughly 1 cm² fragments can increase their growth rates up to 5x. However, extreme early mortality of fragments has been observed in the field, which has been at least partially attributed to predation. It has been …

Bio-Inspired Airfoil Design Based On The Aerodynamic Analysis Of A Bird Feather Microstructure, Jack C. Ihm

College of Graduate Studies: Theses & Dissertations

This study investigates the aerodynamic effects of a bio-inspired airfoil design based on the microstructure of a secondary feather from a female wood duck. The research hypothesized that incorporating barbs and barbules into an airfoil design would modify boundary layer behavior by introducing localized flow disturbances. To test this, a bio-inspired airfoil was developed by integrating the microstructure into a NACA 0012 airfoil and analyzed using computational fluid dynamics (CFD) simulations at angles of attack of 0°, 5°, 10°, and 15°. The results showed that the bio-inspired airfoil influenced boundary layer behavior, producing localized flow disturbances near x/c = 0.7 …

Novel Infection By Mucor Hiemalis Kills Caenorhabditis Hosts Through Intestinal Perforation, Jay Ni

West Chester University Graduate Theses, Dissertations, and Final Projects

The nematode Caenorhabditis elegans has emerged as a popular model system to investigate cell biology and host-pathogen interactions. Presently, C. elegans is studied as a natural host of intracellular pathogens such as microsporidia and Orsay virus along with extracellular bacterial and fungal pathogens. The use of C. elegans as a model in host-pathogen research is limited by the number of naturally occurring pathogens to the organism. Through a sampling project to identify new pathogens of C. elegans, we identified the fungus Mucor hiemalis as a pathogen of Caenorhabditis species. We observed the fungus in the intestinal lumen of wild-caught …

Functional Characterization Of The Hdt5 Gene In Aspergillus Flavus Morphogenesis, Mycotoxin Production, And Fungal Phytopathogenicity, Brenda Omburo

Graduate Research Theses & Dissertations

The present study aimed at elucidating the role of hdt5 in fungal morphology, mycotoxin production and in plant virulence in Aspergillus flavus. Currently, methodologies to prevent the negative impact of A. flavus are insufficient. It is known that expression of the hdt5 gene is dependent on hbx1, a master regulatory gene that affects expression of hundreds of genes in the A. flavus genome, controlling both development and secondary metabolism. However, while the aflatoxin gene cluster has been elucidated, the genetic regulatory mechanisms controlled by hdt5 are not fully understood. For this study, therefore, a complete strain set composed of a …

An Exploration Of Social Isolation’S Effects On The Gastrointestinal And Metabolic Health Of A Social Mammal, Daniel Adam Nuccio

Graduate Research Theses & Dissertations

Human health can be impacted considerably by subjective feelings of loneliness, resulting in mental illness and the dysregulation of normal cardiovascular, immune and endocrine functioning. This occurs because social isolation serves as a form of chronic stress for social mammals, spurring physiological responses akin to those associated with more standard forms of stress. On account of their highly social nature, prairie voles (Microtus ochrogaster) subsequently have become one of the model organisms of choice for investigating the effects of social isolation on the development of disease in social mammals.

This dissertation seeks to expand the scientific community’s understanding of the …

Evaluation And Identification Of Novel Viruses In Wild Fishes Using Varied Molecular Biology Techniques, Clayton Douglas Raines

Graduate Theses, Dissertations, and Problem Reports (ETD)

Viruses are among the most abundant biological entities on Earth, yet their diversity and ecological roles in aquatic vertebrates, particularly fishes, remain poorly characterized. This dissertation advances fish virology through integrative approaches that combine historical context, molecular diagnostics, and genomic discovery. A novel hepadnavirus (ApHBV) was identified in asymptomatic Alosa pseudoharengus, emphasizing the prevalence of subclinical infections in migratory forage species. In Catostomus commersonii, transcriptomic profiling revealed sexually dimorphic immune responses to hepatitis B and C-like viruses, highlighting complex host-pathogen dynamics. In Micropterus nigricans, next-generation sequencing uncovered a novel nackednavirus and multiple adomaviruses within hyperpigmented lesions, expanding …

Molecular Characterization Of Fungus-Arthropod Associations, Angie M. Martin

Graduate Theses, Dissertations, and Problem Reports (ETD)

Arthropods, or phylum Arthropoda, are the largest group of animals, accounting for over three quarters of all animal records on NCBI Taxonomy. And yet, only 40% of all deposited sequences on NCBI Nucleotide come from arthropods. Clearly, arthropods are an understudied group of animals: they are small, often drab, and lead lives very alien to our own. Arthropods have chitinous exoskeletons, segmented bodies, and jointed appendages, and include crabs, barnacles, insects, spiders, and millipedes. Since the era of DNA based studies took off in the 1980s, DNA and other small molecules have been integral to our understanding of the Earth …

Soils From Different Solidago Altissima Clones Mediate Intraspecific Interactions In Schizachyrium Scoparium, Sarah Alharbi

Masters Theses

While previous studies have examined plant intraspecific competition and soil microbial effects separately, fewer studies have investigated how these factors interact, particularly in the context of genotype-specific soil conditioning effects. Plant-soil feedbacks can significantly alter interspecific competitive outcomes, yet few studies have examined how local variation in soil conditioning influences plant responses to density-dependent competition. I investigated how soil inocula derived from four Solidago altissima clones that were previously shown to differ in their soil conditioning effects (Foster et al., 2022) affected the growth and root traits of Schizachyrium scoparium across a gradient of intraspecific competition (1, 2, or 4 …

Molecular Mechanisms Of Kynurenine-Mediated Lifespan Regulation In Yeast, Ryan E. Counterman Jobb

Theses and Dissertations

The kynurenine pathway is a highly conserved pathway that acts as the primary pathway for tryptophan catabolism and has been found to be involved in lifespan regulation across many diverse organisms. Caloric restriction (CR) is the only known dietary intervention to date that both increases the mean lifespan and the health span of multiple organisms, although the molecular mechanisms of these effects are not fully understood. There are known and sometimes contradictory relationships between the kynurenine pathway activity and the life- extending effect of CR but the crosstalk between the two is not well characterized. Understanding these relationships could lead …

Reversible Degradation Of Peptidoglycan By Lytic Transglycosylases, Aaron Devereaux

Theses and Dissertations (Comprehensive)

Antimicrobial resistance continues to be a burden on the global healthcare system with an estimated cost of billions of dollars and millions of deaths each year. Recently, there has been little to no development on new antibiotics to treat bacterial infection, and any that are developed become resisted to within a few years. Both Gram-positive and Gram-negative bacteria contain a mesh-like layer called peptidoglycan (PG) that surrounds their cells providing strength, cell shape, and protection from their environments. This layer is a polymer of N-acetylmuramic acid (MurNAc) and N-acetylglucosamine (GlcNAc) connected via a b-1,4-glycosidic bond, with each strand being cross-linked …

Genomic And Metabolic Network Properties In Thermophiles And Psychrophiles Compared To Mesophiles, Amal Saeed Alblooshi

Theses

Thermophiles and psychrophiles are extremophilic microorganisms that thrive in harsh conditions. Thermophiles are mostly located in hot springs, prosper in high temperatures. Psychrophiles thrive in extremely cold environments, including polar regions and deep-sea habitats. Although they play a crucial role in biotechnology and environmental research, their mechanisms of adaptation are still not well understood. The main objective of this thesis is to understand the genomic characteristics and metabolic network features in thermophiles and psychrophiles compared to mesophiles. The genomes of 59 species among thermophiles, psychrophiles, and mesophiles were collected from the NCBI database. These genomes were used to analyze their …

Evaluation Of Microbial Contamination In Tube Well And Filter Water Of Lahore And Treatment With Copper Nanoparticles, Khadeeja Moazzam, Sumaira Mazhar

Journal of Bioresource Management

Water contamination is a global issue and different techniques are being devised to reduce water contamination. Among these techniques, use of nanoparticles for water purification is an efficient and cost-effective method with minimum or no side effect. Metal nanoparticles are known for their antibacterial activity against various pathogens. Synthesis of these nanoparticles using green synthesis methods minimizes the harmful effects while ensuring their antibacterial activity. Therefore, in the present work, it was aimed to evaluate the microbial contamination in water samples collected from different tube wells and filter plants located in different areas of Lahore, Pakistan for the isolation of …

Interactions Of The Sars-Cov-2 Viral Genome 3’-Untranslated Region With Viral And Host Rnas, Caleb Frye, Mihaela Rita Mihailescu

Electronic Theses and Dissertations

This dissertation focuses on the characterization of RNA-RNA interactions within the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genome and with host microRNAs. As the causative agent of coronavirus disease 2019 (COVID-19), SARS-CoV-2 has evolved rapidly since its appearance. This has warranted prompt characterization of the virus particularly of its single stranded RNA (ssRNA) genome. By using a combination of bioinformatics, biophysics, and/or biological assays, we analyzed the SARS-CoV-2 viral genomic RNA and uncovered interactions of genomic RNA with host RNAs, highlighting an underutilized method of targeting RNA viruses. We showed here that the conserved elements in the viral genomic …

Characterizing The Francisella Tularensis Universal Stress Protein, Benjamin Girardo

Theses & Dissertations

Francisella tularensis is an extremely virulent pathogen responsible for the zoonotic disease tularemia. F. tularensis employs various defense mechanisms to survive and persist under diverse environmental and host-induced stress conditions. Despite its significance, the full spectrum of stress factors that enable F. tularensis persistence remain inadequately understood. In many bacterial species, universal stress proteins (Usp) play a crucial role in managing adverse conditions. The aim of this study was to elucidate the role of Usp in F. tularensis as a means of clarifying the stress response mechanisms of this pathogen. The F. tularensis Usp is encoded by a single, highly …

An In-Depth Investigation Into Yersinia Pestis Phages: Isolating A Yersinia Pestis Phage From Soil And Constructing A Comprehensive Phylogenetic Analysis Of Known Yersinia Pestis Phages, Jacqueline Chavez

All HCAS Student Capstones, Theses, and Dissertations

Yersinia pestis, the causative agent of the plague, has become increasingly resistant to many antibiotics; therefore, alternatives such as phage therapy are necessary. Phage therapy uses combinations of bacteriophages or phages, which are viruses that only infect bacteria. However, phages—especially Y. pestis phages —are severely understudied. Thus, this research has sought to specifically isolate a phage from soil that infects Y. pestis. There were 146 samples that were collected from across the US, focusing on those with reported cases of plague. These samples were enriched with Y. pestis to maximize the amount of potential phage that target Y. pestis. …

Bioindicators Of Mercury In Riverine Systems, Kathryn Mudica

All-Inclusive List of Electronic Theses and Dissertations

This study focuses on the bioaccumulation and biomagnification of mercury in freshwater food webs, with emphasis on bioindicators, such as macroinvertebrates, crayfish, and river otters. Despite regulatory efforts and advancements in monitoring, significant gaps remain in understanding mercury dynamics in freshwater systems—especially regarding its transport, methylation, and bioavailability across different ecosystems. To address these knowledge gaps, this study adopts a biocentric approach, emphasizing the role of living organisms in their environment. By utilizing macroinvertebrates, crayfish, and river otters as bioindicators, we aim to assess mercury bioavailability and distribution. These organisms provide varying temporal and spatial scales of mercury accumulation, offering …

Elucidating The Mechanism Of Interleukin-17a Signaling In The Pathogenesis Of West Nile Virus, Farzana Nazneen

Dissertations

West Nile Virus (WNV), a neurotropic flavivirus transmitted by mosquitoes, is a leading cause of viral encephalitis in the United States and remains a significant public health concern. Unfortunately, no vaccine or therapeutic intervention is available against WNV infection. Previous studies, including ours, demonstrated that interleukin-17A (IL-17A) signaling increases the cytotoxic potential of CD8⁺ T cells to facilitate WNV and parasite clearance; however, the molecular mechanism is not understood. IL-17 receptor C (IL-17RC) is an obligatory co-receptor with IL-17 receptor A (IL-17RA) for signaling induced by IL-17A, IL-17A/F, and IL-17F. In this study, we found that IL-17RC deficient ( …

Analysis Of Microbiome In Various Human Medical Conditions Using Next-Generation Sequencing Of The 16s Rrna Gene, Pallavi Sharma

Electronic Theses and Dissertations

Studies of human microbiomics, spanning diverse anatomical sites, offer a unique perspective into the complex microbial communities within the body. Influenced by age, gender, and disease, it mirrors broader microbial ecosystems. This study specifically delves into the ocular and gastrointestinal tract microbiome, comparing its composition in 43 healthy and diseased patients using 16S rRNA gene sequencing. We identified a rich microbial landscape, identifying over 338 bacterial taxa. Notably, Acinetobacter, Cutibacterium, Acidovorax and Herbaspirillum were prevalent in the ocular samples and Akkermansia, Faecalibacterium, and Anaerostipes were mostly prevalent in gut samples. Moreover, dry eye disease conditions were characterized by …