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Full-Text Articles in Microbiology

Development Of A Urothelial Cell Line Expressing A Caspase-1 Biosensor To Measure Cellular Inflammatory Responses To Potential Uropathogens, Nikita Riya Kesav Aug 2024

Development Of A Urothelial Cell Line Expressing A Caspase-1 Biosensor To Measure Cellular Inflammatory Responses To Potential Uropathogens, Nikita Riya Kesav

Master's Theses

Urinary tract infections are one of the most common bacterial infections, historically implicating Escherichia coli as the causative pathogen. However, it is now known that there are a variety of bacteria that exist within the urinary tract, acting as either beneficial uroprotectives or opportunistic uropathogens. Furthermore, there are significant gaps in our understanding as to how these bacteria interact with the urothelium and what role each plays in maintaining or disrupting homeostasis. Research has shown that Toll-like receptor 4 (TLR4) signaling and Nod-like Receptor Protein 3 play a role in inflammasome activation during infection, triggering caspase-1 activation and inducing release …


Elucidating Enterococcal Mechanisms Underlying Recurrent Urinary Tract Infections, Baylie Hochstedler-Kramer Aug 2024

Elucidating Enterococcal Mechanisms Underlying Recurrent Urinary Tract Infections, Baylie Hochstedler-Kramer

Dissertations

Urinary tract infection (UTI) is one of the most common bacterial infections globally and can lead to life-threatening complications. UTI disproportionately affects females, with the majority of females being treated for at least one UTI in their lifetime. Of the females who develop UTI in their lifetime, almost one third will develop recurrence within six months after initial treatment and many will struggle with UTI recurrence for long spans of their lives. Although recurrent UTI has previously been attributed to persistence of Escherichia coli, recent studies utilizing more sensitive detection methods have shown Enterococcus faecalis is strongly associated with recurrent …


Investigating The Roles Of Sirtuins During Cvb3 Infection And Innate Immunity, Bridget M. Hulsebosch Aug 2024

Investigating The Roles Of Sirtuins During Cvb3 Infection And Innate Immunity, Bridget M. Hulsebosch

Master's Theses

Coxsackievirus B3 (CVB3) is an enterovirus that chronically infects heart tissue, leading to dilated cardiomyopathy. However, no vaccines or antivirals exist for CVB3 infection or to treat CVB3-induced dilated cardiomyopathy, except for a heart transplant. Sirtuins (SIRTs), class III lysine deacetylases, have diverse and complex roles in cellular functions, contributing to energy production, NF-κB signaling, cell cycle regulation, and inflammation. Previous studies showed that SIRTs are essential for hepatitis B and A viral replication and regulate the IFN response during viral infection. However, the role of SIRT1 and 2 during CVB3 infection is entirely unknown. CVB3-infected SIRT1 and SIRT2 knockout …


Time-Transgressive Microbial Diversity In A Tropical Bat Guano Accumulation, Deer Cave, Mulu, Borneo, Joyce Lundberg, Donald A. Mcfarlane Aug 2024

Time-Transgressive Microbial Diversity In A Tropical Bat Guano Accumulation, Deer Cave, Mulu, Borneo, Joyce Lundberg, Donald A. Mcfarlane

International Journal of Speleology

Bat guano accumulations in caves can constitute large deposits of organic material, particularly chitin and its degradation products, that host a diverse microbiome. Previous microbiological studies have not addressed the stratified nature of these deposits in the context of the timeframe of the decomposition process. We present such data (temperature, pH, DNA sampling of eight carbon-dated strata) for a 75 cm-deep tropical guano accumulation that undergoes complete decomposition over a timescale of ~120 years. The aerobic, surface layer of freshly-fallen guano has the greatest diversity of taxa, with Bacteroidota co-dominant with Pseudomonadota, and includes many taxa unique to this …


The Experience Of Homelessness And Its Effects On Gut Eubiosis, Kamerin Villagomez Aug 2024

The Experience Of Homelessness And Its Effects On Gut Eubiosis, Kamerin Villagomez

University Honors Theses

Microorganisms which populate the human gastrointestinal tract (GIT) have a profound effect on overall human health. The relationship between host health and eubiosis, or balance, of the GIT microbiome is symbiotic and can have reciprocal relationships with quality of sleep, quality of diet, stress and mental health, and the experience of pain. These specific aspects of health are unique in populations experiencing homelessness due to the multi-dimensional and complex nature of their lived experience. Very few studies explore populations experiencing homelessness, with even fewer investigating the intersection between this population and the human GIT microbiome. It is important to do …


Investigating The Presence Of Bacterial Phytoplasma Disease In Grasses Of Central Texas And Their Associated Hemiptera, Danielle Rios Aug 2024

Investigating The Presence Of Bacterial Phytoplasma Disease In Grasses Of Central Texas And Their Associated Hemiptera, Danielle Rios

Masters Theses (Archived)

No abstract provided.


The Molecular Detection Of Hemotropic Mycoplasma Species In Dogs, Hafize Tuğba Yüksel Dolgun, Şükrü Kirkan Aug 2024

The Molecular Detection Of Hemotropic Mycoplasma Species In Dogs, Hafize Tuğba Yüksel Dolgun, Şükrü Kirkan

The Thai Journal of Veterinary Medicine

Hemotropic mycoplasmas are uncultured bacteria that cause different degrees of hemolytic anemia in infected hosts. Molecular approaches are used to diagnose hemotropic mycoplasmas since they are difficult to identify using conventional methods. The aim of this study was to use molecular approaches to determine hemotropic mycoplasmas in dogs. Blood samples were collected in tubes (with EDTA) from 100 dogs. After DNA extraction, 100 DNA samples were investigated by PCR. Hemotropic mycoplasma was detected in 12 (12%) samples and positive samples were subjected to Sanger sequencing. Mycoplasma haemocanis was detected in 6 (50.0%) of the samples, Candidatus Mycoplasma hematoparvum in 5 …


Targeting Aspergillus Fumigatus Hypoxia Response Pathways For Novel Antifungal Drug Development., Cecilia Gutierrez Perez Aug 2024

Targeting Aspergillus Fumigatus Hypoxia Response Pathways For Novel Antifungal Drug Development., Cecilia Gutierrez Perez

Dartmouth College Ph.D Dissertations

Invasive fungal disease present are difficult to diagnose and treat and present a high mortality rate across the world with approximately 1.5 million people a year succumbing to fungal infections worldwide. Currently, there are limited antifungal classes used therapeutically, and antifungal drug resistance on the rise further exacerbates the dire need for novel therapeutics with innovative mode of actions. The filamentous fungi, Aspergillus fumigatus is the causative agent of invasive pulmonary aspergillosis (IPA). It is estimated that contemporary antifungals fail in about 50% of patients with invasive filamentous fungal infections, likely due to the biofilm mode of growth exhibited in …


Microbial Phosphate Solubilization Mechanisms In P Solubilizing In Andisol, Agustina Erlinda Marpaung, Tengku Sabrina, Abdul Rauf, Dwi Ningsih Susilowati, Luthfi Aziz Mahmud Siregar Aug 2024

Microbial Phosphate Solubilization Mechanisms In P Solubilizing In Andisol, Agustina Erlinda Marpaung, Tengku Sabrina, Abdul Rauf, Dwi Ningsih Susilowati, Luthfi Aziz Mahmud Siregar

Jurnal Kultivasi

Phosphate (P) nutrient plays a significant role in plant growth and yield. P is an essential element that plays an important role in photosynthesis and root development. Phosphate nutrient availability is deficient in some soil types due to retention, such as in Andisol soil types. High phosphate retention in Andisol soil types causes P nutrients to be unavailable to plants and can reduce crop yields. The availability of P in Andisol soils can be done, among others, by applying phosphate solubilizing microbes. Phosphate solubilizing microorganisms are soil microorganisms consisting of bacteria and fungi that can mineralize organic P, dissolve inorganic …


Inactivated Rabies-Based Lassa Fever Virus Vaccine Candidate Lassarab Protects Nonhuman Primates From Lethal Disease, Gabrielle Scher, Catherine Yankowski, Drishya Kurup, Nicole Josleyn, Eric Wilkinson, Jay Wells, Jesse Steffens, Ginger Lynn, Sean Vantongeren, Xiankun Zeng, Nancy Twenhafel, Kathleen Cashman, Matthias Schnell Aug 2024

Inactivated Rabies-Based Lassa Fever Virus Vaccine Candidate Lassarab Protects Nonhuman Primates From Lethal Disease, Gabrielle Scher, Catherine Yankowski, Drishya Kurup, Nicole Josleyn, Eric Wilkinson, Jay Wells, Jesse Steffens, Ginger Lynn, Sean Vantongeren, Xiankun Zeng, Nancy Twenhafel, Kathleen Cashman, Matthias Schnell

Department of Microbiology and Immunology Faculty Papers

Lassa fever virus (LASV), a member of the Arenavirus family, is the etiological agent of Lassa fever, a severe hemorrhagic disease that causes considerable morbidity and mortality in the endemic areas of West Africa. LASV is a rodent-borne CDC Tier One biological threat agent and is on the World Health Organization's (WHO) Priority Pathogen list. Currently, no FDA-licensed vaccines or specific therapeutics are available. Here, we describe the efficacy of a deactivated rabies virus (RABV)-based vaccine encoding the glycoprotein precursor (GPC) of LASV (LASSARAB). Nonhuman primates (NHPs) were administered a two-dose regimen of LASSARAB or an irrelevant RABV-based vaccine to …


Rna Secondary Structures: Structure-Function Studies In Viral And Neurodegenerative Diseases, Caylee Cunningham Aug 2024

Rna Secondary Structures: Structure-Function Studies In Viral And Neurodegenerative Diseases, Caylee Cunningham

Electronic Theses and Dissertations

The studies within this dissertation highlight the importance of RNA structure and function, highlighting potential mechanisms in the pathogenesis of the SARS-CoV-2 virus and hallmarks of ALS. Specifically, the s2m, a 41-nt structure found within the hyper variable region of the 3’ UTR of the SARS-CoV-2 virus, was investigated as this element has no definitive role in viruses but its high conservation in several viral families warrants investigation. We used various biophysical techniques to determine if a palindromic sequence in the terminal loop could participate in dimerization activities, which may have implications in recombination and the longevity of the virus. …


Growth Improvement Of Immature Quinine By Applying Coffee Husk Compost And Biofertilizer, Yudithia Maxiselly, Dinda Rachmatis Sa'adah, Mira Ariyanti, Muhammad Khais Prayoga, Heri Syahrian Khomaeni Aug 2024

Growth Improvement Of Immature Quinine By Applying Coffee Husk Compost And Biofertilizer, Yudithia Maxiselly, Dinda Rachmatis Sa'adah, Mira Ariyanti, Muhammad Khais Prayoga, Heri Syahrian Khomaeni

Jurnal Kultivasi

The growth of immature Cinchona ledgeriana can be optimized by applying fertilizers to fill the nutritional needs of plants. Nutrients can be provided through the help of microorganisms derived from organic fertilizers and biofertilizers. This study aims to evaluate the effect of applying coffee husk compost and biofertilizer consortium on the growth of immature quinine plants. This research was conducted from November 2023 – January 2024 at Gambung Tea and Cinchona Research Center, Pasir Jambu District, Bandung Regency, West Java. The research used a randomized block design with four replications and six treatments, namely control (Urea 17 g.plant-1 + SP36 …


Growth Response Of Tomatoes To Application Of Bacterial-Coated Npk Fertilizer In A Pot Experiment, Reginawanti Hindersah, Ruhnayati Kaffah, Ayu Siti Aisyah, Mieke Rochimi Setiawati, Mahfud Arifin Aug 2024

Growth Response Of Tomatoes To Application Of Bacterial-Coated Npk Fertilizer In A Pot Experiment, Reginawanti Hindersah, Ruhnayati Kaffah, Ayu Siti Aisyah, Mieke Rochimi Setiawati, Mahfud Arifin

Jurnal Kultivasi

Nitrogen-fixer and phosphate-solubilizer bacteria increase the chemical-fertilizer efficiency and soil health. Bacterial-coated NPK fertilizer is a novel approach for intensifying biofertilizer application in vegetable production. The study aimed to observe the compatibility between two Azotobacter species and two Bacillus species, their population on two formulations of bacterial-coated NPK fertilizer (BCN), and the effect of BCN dose on growth, N and P content, and their uptake in tomato shoots. The compatibility test was performed using the streak method. The population of Azotobacter and Bacillus were counted for two formulations of NPK fertilizer coated by solid biofertilizer (5% and 10%) and zeolite …


Identification And Characterization Of A Skin Microbiome On Caenorhabditis Elegans Suggests Environmental Microbes Confer Cuticle Protection, Nadia B Haghani, Robert H Lampe, Buck S Samuel, Sreekanth H Chalasani, Molly A Matty Aug 2024

Identification And Characterization Of A Skin Microbiome On Caenorhabditis Elegans Suggests Environmental Microbes Confer Cuticle Protection, Nadia B Haghani, Robert H Lampe, Buck S Samuel, Sreekanth H Chalasani, Molly A Matty

Faculty, Staff and Students Publications

In the wild, C. elegans are emersed in environments teeming with a veritable menagerie of microorganisms. The C. elegans cuticular surface serves as a barrier and first point of contact with their microbial environments. In this study, we identify microbes from C. elegans natural habitats that associate with its cuticle, constituting a simple “skin microbiome.” We rear our animals on a modified CeMbio, mCeMbio, a consortium of ecologically relevant microbes. We first combine standard microbiological methods with an adapted micro skin-swabbing tool to describe the skin-resident bacteria on the C. elegans surface. Furthermore, we conduct 16S rRNA gene sequencing studies …


Exploring The Interaction Between Klebsiella Pneumoniae And Clostridioides Difficile At The Mucosal Interface, Taylor D. Ticer Aug 2024

Exploring The Interaction Between Klebsiella Pneumoniae And Clostridioides Difficile At The Mucosal Interface, Taylor D. Ticer

MUSC Theses and Dissertations

The gut microbiota plays a major role in human diseases. The impact of these microbes on human health comes not only from individual microbes but also from their interactions with each other. A prime example of this is Clostridioides difficile, an intestinal pathobiont that causes severe gastrointestinal illness. C. difficile works cooperatively with other gut bacteria, including Klebsiella pneumoniae. We hypothesized that K. pneumoniae would work synergistically with C. difficile and promote its pathogenesis. We screened over 40 K. pneumoniae strains to assess their interaction with the intestinal mucus layer, a key colonization site for C. difficile. …


The Role Of Efflux Pump Inhibitor In Enhancing Antimicrobial Efficiency Of Silver Nanoparticles And Methylene Blue As An Effective Photodynamic Therapy Agent, Yaran Allamyradov Aug 2024

The Role Of Efflux Pump Inhibitor In Enhancing Antimicrobial Efficiency Of Silver Nanoparticles And Methylene Blue As An Effective Photodynamic Therapy Agent, Yaran Allamyradov

Masters Theses & Specialist Projects

Efflux pumps are critical active transport systems utilized by cells to expel toxic substances, including antibiotics and photosensitizer complexes, thereby contributing to antimicrobial resistance. Efflux pump inhibitors (EPIs), which are compounds that obstruct the transport of molecules through these pumps, play a pivotal role in enhancing the effectiveness of antimicrobial therapies against pathogens. This study investigates the effects of the EPI reserpine on the photodeactivation rate of pathogens when used in conjunction with silver nanoparticles (Ag NPs) and methylene blue (MB), a common photosensitizer.

Our research reveals that the application of reserpine, in combination with Ag NPs and MB, leads …


Functional Characterization Of A Lncrna Afu-254 In Stress Response And Pathogenesis Of Aspergillus Fumigatus, Ritu Devkota Aug 2024

Functional Characterization Of A Lncrna Afu-254 In Stress Response And Pathogenesis Of Aspergillus Fumigatus, Ritu Devkota

All Theses

Aspergillus fumigatus is a saprophytic fungus that can cause a collection of diseases termed aspergillosis; the most severe is invasive pulmonary aspergillosis (IPA). Azole is a major class of antifungal drugs used to treat invasive pulmonary aspergillosis. However, in recent years, there has been an increase in fungal resistance to azole drugs, making the treatment of IPA even more challenging. It is becoming increasingly clear that long non-coding RNAs (lncRNAs), i.e., the RNAs that do not translate into proteins, mediated regulation is vital in stress response and pathogenesis; however, the mechanisms of how lncRNA contribute to fungal stress resistance and …


Establishment Of A Novel Prairie Vole (Microtus Ochrogaster) Sars-Cov-2 Infection And Transmission Model, Stephanie Rebecca Kehl Aug 2024

Establishment Of A Novel Prairie Vole (Microtus Ochrogaster) Sars-Cov-2 Infection And Transmission Model, Stephanie Rebecca Kehl

Open Access Theses & Dissertations

Considering that the number of SARS-CoV-2 cases and deaths continues to increase three years after the onset of the pandemic, the need for animal models to study disease pathology and test antiviral effectiveness remains paramount. Prairie voles offer unique advantages as an infection model, such as mirroring human social behavior, including pair bonding and biparental offspring rearing, having inducible estrus and ovulation cycles, and not being overly domesticated. Based on the sequence homology of the vole ACE2 receptor to that of other species that are susceptible to SARS-CoV-2, such as the ferret and hamster, we hypothesized that the vole ACE2 …


Manipulation Of Cellular Proliferating Cell Nuclear Antigen (Pcna) During Herpes Simplex Virus Type 1 Infection, Jessica Packard, Jill A. Dembowski Aug 2024

Manipulation Of Cellular Proliferating Cell Nuclear Antigen (Pcna) During Herpes Simplex Virus Type 1 Infection, Jessica Packard, Jill A. Dembowski

Electronic Theses and Dissertations

Herpes simplex virus type 1 (HSV-1) is a double stranded DNA virus that replicates within the nucleus of host cells. Using accelerated native isolation of proteins on nascent DNA (aniPOND), cellular proteins were found to associate with HSV-1 replication forks. One host factor of interest is proliferating cell nuclear antigen (PCNA), the DNA sliding clamp that tethers DNA polymerases and DNA damage response proteins to replicating cellular DNA. Although HSV-1 encodes its own DNA polymerase processivity factor (UL42), PCNA plays a key role in HSV-1 infection. We used commercially available PCNA inhibitors and short hairpin RNAs (shRNA) to investigate how …


Elucidating The Roles Of Septin Proteins In Thermotolerance And Cell Wall Integrity In Cryptococcus Neoformans, Stephani S. Martinez Barrera Aug 2024

Elucidating The Roles Of Septin Proteins In Thermotolerance And Cell Wall Integrity In Cryptococcus Neoformans, Stephani S. Martinez Barrera

All Dissertations

Cryptococcus neoformans is a globally distributed fungal pathogen responsible for causing cryptococcal meningitis in immunocompromised individuals. This pathogenic yeast must adapt to changes in temperature upon entering the human host. Septin proteins are conserved filament-forming GTPases that assemble as higher-order complexes at the cell cortex to support cytokinesis and morphogenesis in fungal and animal cells. In C. neoformans, four septin homologs (Cdc3, Cdc10, Cdc11, and Cdc12) assemble at the mother-bud neck, contributing to cytokinesis through poorly understood mechanisms. C. neoformans strains lacking the septins Cdc3 or Cdc12 are viable at 25°C, but fail to proliferate at 37°C, and are …


Phylogenomic Analyses Of Three Distinct Lineages Uniting Staphylococcus Cohnii Snd Staphylococcus Urealyticus From Diverse Hosts, L. Caroline House, Amer Hasan, Andi Asnayanti, Adnan A. Alrubaye, Jeff Pummill, Douglas Rhoads Aug 2024

Phylogenomic Analyses Of Three Distinct Lineages Uniting Staphylococcus Cohnii Snd Staphylococcus Urealyticus From Diverse Hosts, L. Caroline House, Amer Hasan, Andi Asnayanti, Adnan A. Alrubaye, Jeff Pummill, Douglas Rhoads

Poultry Science Faculty Publications and Presentations

We sequenced and assembled genomes for 17 isolates of Staphylococcus cohnii isolated from osteomyelitis lesions in young broilers from two separate experiments where we induced lameness using a hybrid wire-litter flooring system. Whole genome comparisons using three different methods support a close relationship of genomes from both S. cohnii and Staphylococcus urealyticus. The data support three different lineages, which we designated as Lineage 1, Lineage 2, and Lineage 3, uniting these two species within an evolving complex. We present evidence for horizontal transfer between lineages of genomic regions from 50–440 kbp. The transfer of a 186 kbp region from …


Investigation Of The Microbiome Of A Recirculating Aquaculture System (Ras) For Crassostrea Virginica Larvae, Isabelle Townsend Aug 2024

Investigation Of The Microbiome Of A Recirculating Aquaculture System (Ras) For Crassostrea Virginica Larvae, Isabelle Townsend

Master's Theses

Recirculating Aquaculture Systems (RAS) offer control over physicochemical and biological factors impacting aquaculture success. One understudied facet of RASs is the water microbiome. Oyster larval microbiomes are shaped by their aquatic microbiomes. Understanding the dynamics of and the factors shaping RAS microbiome may provide insights to how the microbiome can be a tool for optimizing larval production. This study’s goals were to investigate the microbiome stability of a RAS rearing oyster larvae across time and space, determine impacts of larval presence on the microbiome, and examine connections between larvae production outcomes and microbiome stability. Water samples were collected weekly from …


Pilz Domain-Containing Proteins Regulate Motility In Acinetobacter Baumannii, Gabriel Smith Aug 2024

Pilz Domain-Containing Proteins Regulate Motility In Acinetobacter Baumannii, Gabriel Smith

Electronic Theses and Dissertations

Acinetobacter baumannii is an increasingly multidrug-resistant pathogen contributing to hospital-acquired infections, necessitating a greater understanding of how it interacts with its surroundings. Many bacteria utilize different methods of bacterial motility to move about and interact with these surroundings. A bacterial second messenger, cyclic diguanosine monophosphate (c-di-GMP), can regulate various motility factors that are potentially advantageous for survival in and adaptation to their environment. Concentrations of c-di-GMP are regulated by specific synthesizing and degrading enzymes. Controlled levels of c-di-GMP allow interaction between the c-di-GMP and its binding effectors that induce changes in bacterial phenotypes such as biofilm formation and motility. A …


Mechanisms Of Neurodevelopmental Toxicity Of Topiramate, John W Steele, Vaishnav Krishnan, Richard H Finnell Aug 2024

Mechanisms Of Neurodevelopmental Toxicity Of Topiramate, John W Steele, Vaishnav Krishnan, Richard H Finnell

Faculty, Staff and Students Publications

Prescriptions for antiseizure medications (ASMs) have been rapidly growing over the last several decades due, in part, to an expanding list of clinical indications for which they are now prescribed. This trend has raised concern for potential adverse neurodevelopmental outcomes in ASM-exposed pregnancies. Recent large scale population studies have suggested that the use of topiramate (TOPAMAX, Janssen-Cilag), when prescribed for seizure control, migraines, and/or weight management, is associated with an increased risk for autism spectrum disorder (ASD), intellectual disability, and attention-deficit/hyperactivity disorder (ADHD) in exposed offspring. Here, we critically review epidemiologic evidence demonstrating the neurobehavioral teratogenicity of topiramate and speculate …


Uvc And Planetary Habitability: Insights From Desert Lichens And Cyanobacteria, Tejinder Singh Aug 2024

Uvc And Planetary Habitability: Insights From Desert Lichens And Cyanobacteria, Tejinder Singh

UNLV Theses, Dissertations, Professional Papers, and Capstones

An important question in astrobiology is whether life can exist under the levels of UVC radiation found on Archean Earth, Mars, and exoplanets. We investigated this question by studying the UVC survival of colonial cyanobacterium and lichens that grow in harsh desert environments and possess natural sunscreens. We irradiated them nonstop in a desiccated state with a UVC flux closely representing the upper limit on those planets: 55-60 W/m². After irradiation, we rehydrated and assessed their survival using chlorophyll fluorometry and by counting the number of viable colonies that formed on agar plates. All three study organisms survived two to …


Comprehensive Investigation Into The Molecular Mechanisms Driving The Emergence Of Emm4 Group A Streptococcus, Chioma Odo, Samuel A Shelburne, Anthony R. Flores, Steven J Norris, Anna Konovalova, Blake Hanson Aug 2024

Comprehensive Investigation Into The Molecular Mechanisms Driving The Emergence Of Emm4 Group A Streptococcus, Chioma Odo, Samuel A Shelburne, Anthony R. Flores, Steven J Norris, Anna Konovalova, Blake Hanson

Dissertations and Theses (Open Access)

Abstract

Comprehensive Investigation into the Molecular Mechanisms Driving the Emergence of emm4 Group A Streptococcus

Chioma Modeline Odo, M.S.

Advisory Professor: Samuel A. Shelburne, MD, Ph.D.

The major gram-positive bacterium group A Streptococcus (GAS) is a model organism for studying microbial epidemics as it is well known to cause infections that occur in waves. GAS strains are grouped based on the composition of the N-terminal sequence of the M protein which is encoded by the emm gene. With the advent of large-scale whole genome sequencing, GAS clonal emergence events in emm1, emm3, and emm89 types have been identified …


Probing The Ecological Functions Of Thermophiles Using Cultivation-Dependent And Cultivation-Independent Techniques, Dengxun Lai Aug 2024

Probing The Ecological Functions Of Thermophiles Using Cultivation-Dependent And Cultivation-Independent Techniques, Dengxun Lai

UNLV Theses, Dissertations, Professional Papers, and Capstones

High-temperature geothermal springs are ecosystems that resemble early Earth, offering insights into the origins and early evolution of life. In these unique ecosystems, thermophilic microorganisms thrive. However, our knowledge of thermophiles remains limited. A major challenge is that many thermophiles remain uncultivated. The primary goal of this dissertation was to explore the diversity, metabolism, and ecological functions of thermophiles using cultivation-dependent and cultivation-independent approaches. Chapter 1 provides a broad overview of geothermal spring ecosystems and thermophiles, along with a roadmap of the dissertation. Chapter 2 documents a study on the response of specific thermophiles from Gongxiaoshe (GXS) Hot Spring in …


Assessment Of Tce And Chiral Pcb Dechlorination Rate, Congener Diversity, And Enantioselectivity In Town Creek, Sc, Usa Sediment Microcosms, Catherine P. Sumner Aug 2024

Assessment Of Tce And Chiral Pcb Dechlorination Rate, Congener Diversity, And Enantioselectivity In Town Creek, Sc, Usa Sediment Microcosms, Catherine P. Sumner

All Dissertations

Polychlorinated biphenyls (PCBs) and trichloroethene (TCE) are ubiquitous contaminants and are recognized as persistent organic pollutants due to their extreme chemical stability. PCBs were manufactured by chlorinating biphenyls that created 209 congeners with various structures, of which 19 are chiral and can exist as a pair of stable atropisomers. PCBs have been known to cause developmental and neurological toxicity in humans and wildlife; they can act as endocrine disrupters, carcinogens, and teratogens. Sangamo Weston Inc. was an industrial plant located near Town Creek in Pickens Country, South Carolina, that manufactured capacitors and used Aroclors 1016 and 1254 as dialectic fluids …


The Impact Of Reactive Oxygen Species On Bactericidal Activity And Drug Resistance In Salmonella Typhimurium Upon Chlorine And Eugenol Exposure, Mohammed Aljuwayd Aug 2024

The Impact Of Reactive Oxygen Species On Bactericidal Activity And Drug Resistance In Salmonella Typhimurium Upon Chlorine And Eugenol Exposure, Mohammed Aljuwayd

Graduate Theses and Dissertations

Salmonella Typhimurium (S.T) is a foodborne pathogenic bacterium which causes salmonellosis in human beings. Chicken is the most common source of S.T contamination. In chapter I, I discuss the growth of the poultry industry, the role chickens play as Salmonella reservoirs, the spread of drug-resistant strains caused by chicken husbandry and antibiotic use, and how eugenol can be used in poultry feed to decrease Salmonella infections and improve intestinal health. In chapter Ⅱ, I summarize the role of reactive oxygen species (ROS) in bactericidal activity. In chapter Ⅲ, I describe the killing mechanism of sodium hypochlorite (NaOCl) and identify the …


Candida Albicans Farnesol Synthesis And Secretion, Daniel J. Gutzmann Aug 2024

Candida Albicans Farnesol Synthesis And Secretion, Daniel J. Gutzmann

School of Biological Sciences: Dissertations, Theses, and Student Research

Candida albicans is a polymorphic fungus and opportunistic commensal found primarily in the gastrointestinal and skin of healthy individuals. Several barriers prevent C. albicans from causing disease including a healthy immune system and microbiome. When these barriers become comprised, C. albicans can transition to a pathogen and disseminate through the intestinal mucosa leading to life-threatening bloodstream and invasive infections with mortality rates of up to 64%. Morphogenic plasticity is key to this transition and impacts virulence, adaptation to different host environments, and evasion of host immune responses. One regulator of morphogenesis is farnesol. Farnesol is a secondary metabolite of …