Microbiology Commons^™

Skin Of Frog And Scale Of Dragon: Nutritional Cues, Life Cycle Kinetics, And Secretome Dynamics In Batrachochytrium Dendrobatidis, Naomi C. Okada

UNLV Theses, Dissertations, Professional Papers, and Capstones

Nearly 50% of amphibian species are at risk of extinction, making them the most threatened group of vertebrates on the planet. A major driver of these declines is the pathogenic chytrid fungus Batrachochytrium dendrobatidis (Bd), which causes the fatal skin disease chytridiomycosis. Since its discovery in the late 1990s, Bd has been directly implicated in the extinction of 90 species of amphibians and the declines of hundreds more. Despite this devastating ecological impact, relatively little is known about its basic cellular biology.

Bd has a multi-stage asexual life cycle consisting of a motile and infectious zoospore, which encysts (into a …

Characterizing The Microbial Structure And Function In Black Soldier Fly Digested Dairy Manure And Subsequent Larvae, Branden N. Pierce

Theses and Dissertations

This work examined the microbial structure and gene expression found in Black Soldier Fly larval guts and their frass when reared on dairy cattle manure that had been amended with either R. rhodococcus 21198, P. polymyxa 8158, or both and compare the results to larvae reared on untreated manure. First an overview of literature surrounding projected global food supplies and the possible use of insects to either increase them or mitigate the environmental effect of producing said supply. A cellulose degradation assay was performed to assist in determining which bacterial species to use as amendments. Characterization of the microbial communities …

Impact Of The Dose And The Number Of Transmitted/Founder Viruses On Siv Dynamics, Sunil Maity, Vitaly V. Ganusov

Biology and Medicine Through Mathematics Conference

No abstract provided.

The Influence Of Prosthetic Obturators On Quality Of Life In Individuals With Maxillectomy Defects, Minseok Kim

Oral Health

Abstract

Introduction: In recent years, there has been a growing focus on understanding the impact of oral cancer on patients' quality of life. Prosthetic rehabilitation techniques, such as maxillary obturators, often in conjunction with reconstructive surgery, have emerged as interventions to address the challenges posed by post-maxillectomy abnormalities.

Objective: This study aims to systematically review and evaluate the effectiveness of maxillofacial prosthetic rehabilitation using obturators in enhancing the quality of life of patients following maxillectomy.

Methodology: Systematic review of identified literature spanning the timeframe from 2000 to 2020 was used. The comprehensive search encompassed widely recognized databases including PubMed, …

Impacts Of Salinity On Microbial Enzyme Activity In Coastal Waters, Natali Ariyoshi

Honors Theses

Microbial extracellular enzymes are critical for the breakdown of organic matter and nutrient cycling in aquatic ecosystems. Extracellular enzyme activity serves as an indicator of nutrient turnover rates, metabolic states, and nutrient limitations within an ecosystem. Coastal ecosystems are especially dynamic as the influx of freshwater from inland runoff or seawater intrusion from storm surges can lead to fluctuations in salinity which can restructure microbial communities and alter enzymatic activity. Despite the ecological significance of these changes, few studies have explored the effects of short-term salinity shifts on microbial extracellular enzyme activity in coastal waters. This study investigated the effects …

Antibiotic Resistance Patterns In Bacterial Isolates From Mississippi Gulf Coastal Environments, Lawler F. Horn

Honors Theses

Coastal environments host diverse microbial communities that play essential ecological roles but may also serve as reservoirs for antibiotic-resistant bacteria. This study investigated patterns of antibiotic resistance in microbial isolates collected from public beaches along the Mississippi Gulf Coast. A total of 143 bacterial isolates exhibited growth and were included in antibiotic susceptibility screening. High levels of antibiotic resistance were observed, with 137 of 143 isolates showing growth on vancomycin, 124 on amoxicillin, and 102 on erythromycin. Resistance to kanamycin (19/143 isolates) and tetracycline (33/143) was less common. Multidrug resistance was widespread, with 101 isolates (70.6%) resistant to three or …

Acquisition Behavior Response: Investigating The Ability Of Leptoglossus Phyllopus To Choose Between A “Good” Versus “Sub-Optimal” Strain Of Caballeronia, Irene L. Pham

2026 Spring Honors Capstones Projects

Leptoglossus phyllopus is a polyphagous pest that primarily feasts on citrus, tomatoes, and legumes. They must form a mutualistic symbiosis with Caballeronia every generation by ingesting the bacterium from their environment. However, not all species of Caballeronia confer the same fitness on the L. phyllopus host, raising the question of whether L. phyllopus possesses a partner choice mechanism that would allow it to distinguish between a good (GAOX1) and a suboptimal (Lep1P3) symbiosis partner. This was examined by conducting a choice experiment in which the two symbionts (GAOX1 vs. Lep1P3) were placed in a plastic box, and the bug’s roaming …

An Investigation Of Entamoeba Histolytica Chitin Synthases And Other Encystation Factors In Early Encystation, John N. Talledo

All Theses

Entamoeba histolytica is a food-and-water-borne human protozoan pathogen that relies on a two-stage life cycle for successful proliferation outside of the host. E. histolytica exists in its dormant cyst form while outside of its host and converts to the motile trophozoite (amoeba) form in the small intestine. The trophozoites colonize the large intestine to cause symptomatic disease in ~10% of infections, resulting in ~100 million cases of amoebic dysentery each year. Trophozoites can convert back to the cyst form, which is shed in feces to continue the infection cycle.

Currently, there is a lack of understanding of the exact molecular …

Belowground Consequences Of Herbivory In Tomatoes And Cucumbers And Its Lasting Effects, Anthony Ignacio Barrera

Theses, Dissertations and Culminating Projects

Plants recruit soil microorganisms to help mediate biotic stressors such as herbivory, forming dynamic communities in the rhizosphere known as the root microbiome. This study investigated whether artificial herbivory could induce shifts in the root microbiome of tomato (Solanum lycopersicum) and cucumber (Cucumis sativus) and whether those shifts could be transferred to subsequent plants as a soil legacy effect. Plants were grown in sterilized or non-sterilized soil with or without simulated herbivory across two experimental phases, with Phase 2 plants receiving inoculum conditioned by Phase 1 plants. Bacterial community composition was assessed via 16S rRNA amplicon sequencing and analyzed using …

Ai×Life 2026: Advances In Computational Biology Across Scales For Life & Health Sciences, Suma Mohan S., Devika N. T., Pranavathiyani G.

Conference Proceedings

Book of Abstracts of the International Conference, AIxLife 2026: Advances in Computational Biology Across Scales for Life & Health Sciences, held on 17–18 April 2026, SASTRA Deemed to be University, Thanjavur, Tamil Nadu, INDIA 

About the Conference

Conventional computational biology laid the foundation for biological data analysis through statistical models, algorithms, and curated databases, enabling insights into genes, proteins, and pathways. Today, the integration of artificial intelligence, spanning machine learning, deep learning, and large language models (LLMs) is driving a transformative shift across biological scales, from atomic and molecular interactions to pathways, cellular systems, organisms, and populations.

AI-powered approaches …

Descriptive Comparative Analysis Of Bacteriophage And Auxiliary Metabolic Gene Diversity In Marine And Wastewater Environments, Andrew Crawford

Undergraduate University Honors Capstones

Bacteriophages (phages) are viruses that infect bacteria and play a role in bacterial evolution. Through horizontal gene transfer (HGT), phages integrate parts of their genomes into their bacterial hosts. While the molecular mechanisms of this process are well understood, the evolutionary impacts remain less certain. One evolutionary explanation is that auxiliary metabolic genes (AMGs) modulate host gene expression to favor phage reproduction or improve the host’s survival. AMG can persist in hosts' or phages' genomes across future generations, altering their contributions to the ecosystem and posing a concern for human and environmental health. The objective of this project is to …

Bottles, Butterflies, And Biomass: Recycled Glass Sand, Microbial Additions, And Herbivory Effects On Milkweed Growth, Kealey Skinner

Honors Theses

Plant-soil-microbe interactions are integral components of ecological networks and drive ecosystem function from the bottom-up. Whereas herbivores regulate ecosystem function from the top-down, having opposing and potentially complementary effects on ecosystem function. My thesis sought to understand how below-ground microbial communities contribute to herbivore preference and plant biomass across varied soil substrates. My thesis asked: how do substrate and soil microbial communities influence herbivore preference and plant biomass accumulation on swamp milkweed (Asclepias incarnata)? To address this question, seedlings of A. incarnata were sown in 2.5 cm wide × 10 cm deep pots filled with either natural beach sand or …

Identifying The Role Of Human Dna Polymerase Delta During Human Cytomegalovirus Genome Synthesis, Rachel Laree Dansereau

Dartmouth College Master’s Theses

Human cytomegalovirus (HCMV) is a large double stranded DNA virus and member of the Herpesviridae family. Like all herpesviruses, HCMV presents with characteristics of persistent, lifelong infections that transition between lytic and latent states. The replication of the viral genome is traditionally thought to occur by a rolling circle mechanism, but this model is supported by little evidence. It is known that HCMV actively recruits several host proteins to viral replication compartments (RCs), including proteins involved in the DNA damage response (DDR). The exact mechanisms of how these proteins are used and in what ways they help the virus remain …

Urea-Based Boronium Salts As Antimicrobial Agents, Gabriel Allen Merchant

Honors Theses

Quaternary ammonium compounds (QACs) are widely used in disinfectants due to their ability to inhibit the growth of and eliminate microbes. The potency, broad-spectrum activity, and low cost of QACs have made them a cornerstone of modem hygiene. In recent years, QACs have garnered many health and safety concerns due to their overuse and subsequent accumulation in the environment. The increased use of QACs has further led to an increase in antimicrobial-resistant bacteria, making the synthesis of novel antibacterial compounds vital to combat this growing threat. Recent advances in boronium salts offer a unique alternative to address these adverse effects. …

Fingernail Enhancement Microbiomes Study, Kendall E. Bare

Undergraduate Honors Theses

Policies in healthcare regarding fingernail enhancements have not been supported by current science. This study examined bacterial colony growth on gel nail enhancements, regular nail polish, and bare natural nails to evaluate which condition harbors the least bacterial microbiota. The hypothesis proposed that gel enhancements would demonstrate the lowest bacterial counts compared to regular polish and unpolished nails. This investigation was conducted in the context of a local healthcare system dress code policy permitting only regular nail polish in clinical settings. Six participants volunteered and underwent nail swabbing in a microbiology laboratory using sterile cotton applicators and a neutral solution. …

Understanding Tlr3 Immune Response Activation In Cryptosporidium Parvum And Cryspovirus Pathogenesis, Surayya Hudayberganova

Biochemistry and Molecular Biology

Cryptosporidiosis is a serious gastrointestinal illness caused by a protozoan parasite known as Cryptosporidium. It is particularly dangerous for malnourished children and those with compromised immune systems. My research focuses on the Toll-like receptor 3 (TLR3) response to the Cryptosporidium parvum infection, specifically in the presence of the parasite’s viral mutualist named cryspovirus (CSpV1). Results using research methodologies like ELISA and RT-qPCR have indicated that TLR3 expression increases during the infection process of Cryptosporidium parvum (C. parvum). Furthermore, one intriguing observation concluded during this study suggests that administering the TLR3-specific inhibitor CU-CPT4a to infected cells drastically decreased this activation. This …

College Of Natural Sciences Spring Newsletter, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

[Page 1] Dean's Message
[Page] 2 Awards & Recognitions // Student Spotlights
[Page] 3 Zhang Named to Landsat Science Team // The Power of Teaching
[Page] 4 “Science as Art” Competition Welcomes High School Artists
[Page] 5 Testing for “Forever Chemicals” in Surface Water // New Faculty Spotlight
[Page] 6 Ambassador Initiated Outreach
[Page] 7 57th Annual Geography Convention
[Page] 8 Twice the Impact on On Call with the Prairie Doc
[Page] 9 Making Staple Foods Healthier // Halaweish & Cole-Dai Retire
[Page] 10 Drone Day 2026
[Page] 11 Student Research, Scholarship, and Creative Activity Day (SRSCAD)
[Page] 12 Ceremony …

Genetic Screen For Regulators Of Pol4, A Dna Repair Polymerase In Saccharomyces Cerevisiae, Pasang Dolma Sherpa

Theses and Dissertations

In Saccharomyces cerevisiae, DNA polymerase 4 (POL4) is the beta repair polymerase, the product of the POL4 gene, and is involved in base excision repair (BER) and microhomology-mediated end joining (MMEJ). Despite its involvement in these repair pathways and its conservation across eukaryotes, deletion of POL4 shows no detectable phenotype under standard laboratory conditions. I hypothesized that unknown genes act as backup systems, providing redundant activities that allow pol4Δ cells to survive. To test this, a genetic screen for mutants showing synthetic lethality with pol4Δ was implemented. I constructed a strain lacking the POL4 gene and carrying …

Genome-Wide Phenotypic Characterization Of Mycobacteriophage Mercurio, Tyler Downs

Departmental Honors & Graduate Capstone Projects

Bacteriophages, or phages, are being piloted as a supplemental or alternative therapeutic to antibiotics against drug-resistant Mycobacterium pathogens, such as M. tuberculosis, which pose a global public health crisis.  Characterizing bacteriophage genomes can provide insights into efficacy in phage therapy before implementation or elucidate new targets to manipulate bacterial growth.  Overexpression of individual phage genes is useful to study a gene product’s function independent of others.  Here, the results of phage Mercurio plasmid library overexpression in plate-based assays are described.  Mercurio infects nonpathogenic Mycobacterium smegmatis and is genetically related to bacteriophages infecting pathogenic Mycobacterium species.  Eleven gene products of …

The Impact Of Glucose Exposure On Organic Cation Transporters (Oct) Function In A Corneal Epithelial Cell Line, David A. Garza

Theses & Dissertations

Organic cation transporters (OCT) facilitate the movement of neurochemicals and medications, contribute to the removal of cellular waste, and facilitate neuronal communication. Three subtypes of these high-capacity, low-affinity transporters (OCT1, OCT2, and OCT3) are differently expressed in peripheral tissues such as the liver, kidneys, as well as the central nervous system. OCTs are also expressed in ocular tissues. Chronic hyperglycemia is a complication commonly associated with diabetes that can lead to ocular diseases such as diabetic keratopathy, which affects the cornea. In this project, we expose immortalized human corneal epithelial cells (HCE-S) to various glucose concentrations to study their impact …