Life Sciences Commons^™

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

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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 …

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

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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 …

Developing Disinfection Strategies For Controlling Human Norovirus, Sars-Cov-2, And Clostridioides Difficile Endospores In Long-Term Care Facilities, Jinge Huang

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Long-term care facilities (LTCFs) provide an environment favorable for the transmission of three critical human pathogens: human norovirus (HuNoV), severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and Clostridioides difficile. Given residents in LTCFs are susceptible to infections due to their advanced ages and compromised immune systems, effective environmental surface disinfection plays a crucial role in controlling the spread of human pathogens within these settings and, therefore, mitigates the risk of infections caused by these pathogens. This dissertation aimed to assess the efficacy of various types of disinfectants against two HuNoV surrogates [feline calicivirus (FCV) and Tulane virus (TuV)], two …

Effect Of Authentic Kefir And Nigella Sativa On Broilers Challenged By Coccidia And Clostridium Perfringens, Julian E. Nixon

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Black seed oil concentrations of 0%, 0.1%, 1% and 5% were added to milk inoculated with kefir grains and incubated at 25°C for 22 h. The pH and microbial count indicated 1% black seed oil caused low inhibition (P > 0.05) of fermentation, but 5% black seed oil caused significant inhibition of the kefir microorganisms (P < 0.05).

Cobb 500 male chicks (n = 256) were distributed in a randomized block design and received one of four treatments: CTRL1 (Non-medicated, no kefir, no Clostridium perfringens), CTRL2 (Non-medicated, no kefir, C. perfringens inoculated), CTRL3 (BMD medicated, no kefir, C. perfringens inoculated), KTRT (Non-medicated, …

Elucidating Acetate Metabolism: Identification Of Transporters And Enzymes Required For Acetate Utilization In The Fungal Pathogen Cryptococcus Neoformans, Perry L. Kezh

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Cryptococcus neoformans is the leading cause of fungal meningitis world-wide. While exposure to this environmental sporophyte is common during childhood, those who are immune compromised are at risk of infection. Following inhalation, this basidiomycetous fungus subsequently colonizes other organs though hematogenous dissemination, eventually crossing the blood brain barrier and colonizing the brain where it causes as cryptococcal meningitis. Changes in the availability of carbon sources stemming from the movement from soil to the lungs induce changes in fungal metabolism. Specifically, alveolar macrophages, which present a first line of defense against infection, provide a glucose-/amino acid-poor environment. As such, the use …

Diagnosis Of Urinary Tract Infections And Rapid Molecular Characterization Of Antibiotic Resistance, Mohammed Harris

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Urinary tract infections (UTIs) are one of the most common infectious clinical entities in both community and hospital settings. They have a broad range of clinical severity yet inflict large epidemiological burden of morbidity and mortality on patients and the healthcare system with billions of dollars in cost of treatment. Understanding what methods are optimal for diagnosing UTIs are critical to mitigate the marked impact and cost of these infections.

Chapter 1 and 2 in this work surveys the broad array of diagnostic modalities for UTIs and highlights their advantages and limitations in the context of the current standard of …

Microbial, Chemical, And Functional Components In Kefir, Natto, And Feed Ingredients, Dana Mccurdy

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Kefir grains were purchased from online, home kitchen vendors in the United States (n = 22), inoculated into UHT milk, and incubated at 25°C for 22 hours. Results indicated lactobacilli, lactococci and yeast in all samples. Six out of 11 samples contained coliform, and all samples contained pseudomonal and staphylococcal species. Using targeted genome sequencing (16S) of kefir grain samples 1, 2, and 3 revealed that lactobacilli were the predominant genera of bacteria. ITS sequencing revealed different fungal species in each grain. Results indicated potential presence of menaquinone-4 and menaquinone-7 by UPLC-MS/MS analysis.

The fermentation of whole and ground soybeans, …

Effects Of Continuous In Situ Low-Dose Ionizing Radiation On Microorganisms, Molly E. Wintenberg

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Precise detection and monitoring of nuclear fuel cycle, enrichment, and weapon development activities are critical for supporting warfighter preparation in chemical, biological, radiological, nuclear, and explosives (CBRNE) operations, clandestine activities, and nuclear compliance. A biological sensing system could serve as an alternative to traditional detection methods by using organic material naturally present in the environment to discreetly detect residual trace nuclear material. Microorganisms provide an optimal platform for an alternative sensing system; however, their response to low levels of ionizing radiation is poorly characterized. Combining the power of next-generation sequencing and transcriptomic analysis, this dissertation takes an approach to obtain …

Dynamics Of The Supragingival Dental Plaque Microbiome And Its Implications In Early Childhood Caries (Ecc), Lauren O'Connell

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Early childhood caries (ECC) is one of the most common chronic diseases worldwide and remains a serious public health crisis in developing countries and socioeconomically disadvantaged communities. Caries is a complex polymicrobial, sugar-driven disease caused by interactions between the biofilm and tooth surface. While there is a general understanding of the microbial processes driving dental caries development and progression, the microbiota associated with the initiation and progression of dental caries have yet to be fully characterized. The most-studied species associated with tooth health and disease are the oral streptococci. Nevertheless, there are still large gaps in our knowledge of the …

Bacterial Diversity And Ecology Of Two Cryptoendolithic Habitats In The Grand Staircase Escalante National Monument, Utah, Usa, Sukhpreet Kaur

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Sandstone outcrops in the Grand Staircase Escalante National Monument, Utah are host to cryptoendolithic communities dominated by cyanobacteria. These communities produce extracellular polymeric substances that not only aid their survival, but also support other heterotrophic bacteria. Developing a better understanding of the role of these cryptoendolithic communities requires a deeper knowledge of the microbial diversity present. We analyzed the cryptoendolithic bacterial communities in the Jurassic Navajo Sandstone samples collected from several microgeological features associated with a large sandstone dome. These communities clustered into distinctive groups that correlated with topography, suggesting that moisture availability plays an important role in shaping the …

Phosphotransacetylase And Xylulose 5-Phosphate/Fructose 6-Phosphate Phosphoketolase: Two Eukaryotic Partners Of Acetate Kinase, Tonya Taylor

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Although acetate is a predominant metabolite produced by many eukaryotic microbes, far less attention has been given to acetate metabolism in eukaryotes than in bacteria and archaea. Acetate kinase (Ack), which catalyzes the reversible phosphorylation of acetate from ATP, is a key enzyme in bacterial acetate metabolism. Ack primarily partners with phosphotransacetylase (Pta), which catalyzes the generation of acetyl phosphate from acetyl-CoA, but can also partner with xylulose 5-phosphate/fructose 6-phosphate phosphoketolase (Xfp), which produces acetyl phosphate from either xylulose 5-phosphate or fructose 6-phosphate. The Ack-Pta pathway, found primarily in bacteria, is also present in lower eukaryotes such as the green …

Validation Of Thermal Destruction Of Pathogenic Bacteria In Rendered Animal Products, Mary Hayes

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This study tested enumeration techniques for high fat food matrices and determined thermal death times in rendering animal products. Standard Class O phosphate/magnesium chloride dilution buffer series (Dilution Series A) and a modified (pre-warmed to 32oC) lecithin phosphate dilution buffer series (Dilution Series B) were used to enumerate a Salmonella cocktail from both poultry and beef rendering materials. Results of this study indicate use of a modified lecithin buffer did not improve Salmonella enumeration accuracy from rendering materials. Instead, the results suggested use of xylose lysine deoxycholate agar (XLD) with either buffer system accurately enumerated Salmonella from rendering materials. The …

Studies Of Molecular Mechanisms Of Cranberry Mediated Healthspan Promotion In Caenorhabditis Elegans, Sujay Guha

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Extensive studies have demonstrated the potent ability of many nutraceuticals to alleviate the symptoms of aging and stress. We found that cranberry extract (CBE) supplementation at an optimum concentration could prolong Caenorhabditis elegans (C. elegans) lifespan in a manner of daf-16 and osr-1 dependence. Considering that aging is a progressive degeneration of physiological functions, it is intriguing to know whether CBE consumption may delay the age-related degenerative changes in animals. Thus, we examined the effect of CBE consumption on healthspan in C. elegans populations with different ages and age-related disorders. Our results suggest that long-term CBE supplementation leads to a …

Functionalized Nanomaterials And Their Biological Applications, Pallavi Vedantam

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Bionanomaterials have been used in drug delivery, cancer therapy and biodiagnosis of pathogens based on their size and surface functionalization. In this present work, different kinds of nanoparticles (NPs), their cellular interactions, cytotoxicity profiles, and finally role of gold nanoparticles (GNPs) in biodetection of E. coli was investigated.
Firstly, cytotoxicity profiles of commercial, laser ablation, and green synthetic NPs were studied. Induction of apoptosis in cancer cells was found to be size dependent. The plain 80 nm GNPs and AgNPs enhanced toxic effects in cancer cells when compared to 20 nm ones. Apoptotic profiles of ALB- or FBS-coated NPs were …

Analysis Of The Interaction Of Francisella Tularensis Lvs And Legionella Pneumophila Biofilms With Components Of The Aquatic Environment, Uma Mahajan

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Biofilms are complex communities of organisms enclosed in a matrix (EPS) composed of polysaccharides, proteins and DNA. Biofilms are the base of the aquatic ecosystem and interact with the biotic as well as the abiotic components in the environment. Biofilms interact with biotic components of the environment such as protozoa and aquatic invertebrates. In this project, the biotic interactions of Francisella tularensis LVS biofilms are studied in relation to the mosquito larvae of Culex quinquefasciatus. F. tularensis is the causative agent of tularemia and is transmitted by ticks, deer flies, and mosquitoes. Mosquitoes are believed to play a role in …

Thermal Inactivation Of Stress Adapted Pathogens In Compost, Randhir Singh

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In the United States, 1.3 billion tons of animal wastes are produced annually. Disposal of this huge amount of waste on agricultural land without proper treatment is a public health safety issue as animal waste is a potential source of several human pathogens. Therefore, composting of animal wastes is an economical solution to this problem. The high temperature reached during this process also brings about inactivation of pathogens in the waste. However, survival of pathogens has still been reported from different composting studies, indicating the complex nature of this process. The objectives of this study were to: 1) study thermal …

Developing Strategies To Control Human Pathogens In Minimally-Maintained Dairy Manure-Based Compost Heaps, Marion Shepherd

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Composting has been proven to be an effective method used to inactivate pathogens in dairy manure. However, research has shown that if the compost heaps are unturned pathogens can persist, especially on the surface of the heaps for extended periods of time. As such, it is important to evaluate potential interventions that can be used to ensure that pathogens are inactivated at all locations of minimally maintained compost heaps under field conditions. The objectives of this study were to: 1) determine the impact of compost initial carbon-to-nitrogen (C:N) ratio on pathogen destruction when composting dairy manure in unturned heaps, 2) …

Effect Of Goldenseal (Hydrastis Canadensis) On Bacterial Multi Drug Resistant Efflux Pumps, Jyothi Rangineni

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Multi-Drug Resistance (MDR) efflux pumps have been increasingly reported in Gram negative and Gram positive bacteria. These efflux mechanisms pump out a wide variety of structurally unrelated antimicrobials thus leading to a low susceptibility due to lowered intracellular concentrations. The activity of such antimicrobials can be restored by the inhibition of the multi drug efflux pumps. Several MDR pump inhibitors which inhibit the efflux mechanisms in bacteria have been identified. Reserpine and verapamil are two such inhibitors, showing considerable effect on the MDR pumps. But the concentrations required to achieve these effects are too high to be clinically relevant. Reserpine …

Activities Of Muscadine Grape Skin And Polyphenolic Constituents Against Helicobacter Pylori, Joseph Brown

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Helicobacter pylori is a microaerophilic, gram-negative bacterium and among the most persistent of all human pathogens. Its presence in the gastric environment is corre-lated with diseases such as gastritis, peptic ulcers, mucosa-associated lymphoid tissue lymphoma, and gastric carcinoma. Multiple factors are believed responsible for disease progression and outcome including infecting strain(s) genetic composition, age of acqui-sition, host immune response, environment, and diet. Due to the complexity of H. pylori infection, all possible host-pathogen interactions should be considered. One important factor frequently underplayed is host dietary habits which may serve a more important role during and immediately following infection with H. …

Development And Characterization Of Novel Sub-Coatings With Polymorphic Brookite Titania Nanoparticles: Enhanced Uv/Vis Photocatalytic Antibacterial And Anticancer Properties, Donna Weinbrenner

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ABSTRACT
Nosocomial and community infections and biofilm formation from bacteria has increased significantly through adaptation combined with overuse of broad spectrum antibiotics. Because the world population continues to escalate, hospitals and long-term managed care will also escalate, thereby increasing transmission of infections, lowering patients' quality of health. Another disease on the rise throughout the world is skin cancer. A treatment modality that would cause less deleterious effects on the patient would be ideal. These two seemingly different issues could be solved with one product. First an inexpensive, safe, and non-selective antimicrobial surface coating would enhance the hospital arena and a …

Sequencing And Functional Analysis Of A Multi-Component Dioxygenase From Pah-Degrading Sphingomonas Paucimobilis Epa505, Renuka Miller

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Polycyclic aromatic hydrocarbons (PAHs) are hydrophobic organic compounds consisting of two or more fused benzene rings. PAHs derive from many different sources including petroleum refining, wood treatment, and coal coking industries. Because of their structural stability and water insolubility, PAHs are extremely resistant to degradation. These compounds are also believed to have mutagenic, carcinogenic, and teratogenic effects. Therefore, there are currently 16 PAH compounds on the EPA's list of priority pollutants.
Many species of bacteria have the ability to breakdown these persistent pollutants. However, bioremediation strategies using these organisms have many unresolved issues. While laboratory experiments can easily demonstrate the …

Sequence Analysis And Characterization Of The Dihydrodiol Dehydrogenase And Aldehyde Dehydrogenase Genes In'' Sphingomonas Paucimobilis'' Epa505, Jaleh Jalili

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A bacterial artificial chromosome (BAC) library was previously constructed from genomic DNA of Sphingomonas paucimobilis EPA505 at Clemson University Genomic institute (CUGI). To isolate and identify the bphB gene from the genome of S. paucimobilis EPA505, a set of primers was designed based on conserved regions of the bphB gene encoding dihydrodiol dehydrogenase of Sphingomonas CHY-1 and Sphingomonas yanoikuyae B1. Routine PCR was performed and a PCR fragment of approximately 500 bp that confirmed the presence of pbhB gene in Sphingomonas paucimobilis EPA505 was produced. Hybridization of the PCR product with BAC library was performed and one hundred two positive …

Prevalence And Biological Control Of Salmonella Contamination In Rendering Plant Environments And The Finished Rendered Meals, Brandon Kinley

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Although the rendering process serves as invaluable means for the disposal of inedible animal by-products, the finished products often harbor pathogenic and opportunistic microorganisms such as Salmonella and enterococci, respectively. The temperatures used during the rendering process far exceed the heat tolerance threshold of most bacterial species, so cross-contamination from the environment and/or from the incoming raw material is the proposed source of the contamination. Research has demonstrated that the raw material coming into the rendering facility is highly contaminated with pathogenic bacteria including Salmonella. While not in a rendering facility, studies have also demonstrated that bacteria such as Salmonella …

Gene Expression Profile Of Tumor Cell-Fused Or Noni (Morinda Citrifolia)-Treated Dendritic Cells, Melissa O'Connor

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Dendritic cell-mediated cancer immunotherapy employs several ways to engage tumor antigens. We have demonstrated both in pre-clinical animal studies and early clinical trials that dendritomas, highly purified hybrids between dendritic cells and tumor cells, are superior activators of anti-tumor immunity. In the present study, we examined the expression profile of several inflammatory chemokine and chemokine receptors of dendritomas by RNA microarray and real-time RT-PCR. The results indicate that dendritomas made from immature DCs and tumor cells express higher levels of CCL3, CCL5, and CCL22 and lower levels of CCR2 and CCR5, which mimics LPS matured DCs, while dendritomas made from …

Red Raspberries Possess Anticarcinogenic And Immunostimulatory Potential, Jason God

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Despite the great strides made in the treatment of cancer, considerably little progress has been made towards prevention of the disease. In light of this reality, it has become apparent that a greater focus needs to be devoted to research into means of cancer prevention. Due to the significant role that nutrition plays in the development of cancer, the diet presents an attractive and logical target for such research.
Epidemiology has consistently shown an inverse relationship between fruit and vegetable consumption and risk for developing cancer. Additionally, countless in vitro studies on natural products isolated from fruits and vegetables have …

Recombinant G3 Domain Protein Of The Rat Laminin-5 Α3 Chain Binds To Integrins On Tumorogenic Breast Cancer Cells To Induce Apoptosis, Brittany Turner

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The extracellular matrix (ECM) is a network of proteins for holding tissues and cells together. Among the constituents of the ECM is the large molecular weight glycoprotein laminin. Laminin is predominately found in the basement membrane of tissues. Laminins are composed of α, β, and γ chains with 5 globular (G) subdomains at the carboxyl (C) terminal end of the α chain. Of the 12 different laminin isoforms, laminin-5 has been targeted for cancer research. Specifically, the G3 domain has been studied as the specific binding domain. Cells are able to migrate through cell surface adhesion receptors known as integrins. …

Fungal Conversion And Supercritical Carbon Dioxide Processing For Value-Added Canola Oil, Meidui Dong

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There is a growing awareness of health benefits of polyunsaturated fatty acids (PUFAs) e.g. arachidonic acid (ARA, C20:4n6) and eicosapentaenoic acid (EPA, C20:5n3). In general, plant seed oil and animal fat do not contains long-chain PUFAs with more than eighteen carbons. This study investigated the feasibility for addition of ARA and EPA to canola oil through the fermentation of fungi, Mortierella alpina, using canola flake, cake or meal as substrates. Supercritical CO2 extraction was also investigated for lipid extraction. In addition, a supercritical CO2 explosion process was characterized and applied to enhance oil extraction using supercritical CO2 and to potentially …

Laboratory And Field Responses Of Target And Non-Target Species To Algaecide Exposures, Bryand Duke

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In order for water resource managers to effectively and efficiently react to algal growths that are prohibiting use of a lake, reservoir or stream, information must be obtained on the response of the specific algae in site waters to algaecide exposures. In the absence of this information, ineffective algaecides or excessive treatments may be implemented. Research on development of an efficient algaecide assay using site specific samples could contribute to better decisions regarding algaecide applications and increase margins of safety for non-target species. Since these laboratory experiments provide predictions of responses of algae in site waters to algaecide exposures, these …

Identification Of The Rassf3 Gene As A Potential Tumor Suppressor Responsible For The Resistance To Mammary Tumor Development In Mmtv/Neu Transgenic Mice, Isabelle Jacquemart

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The MMTV/neu transgenic mouse line is a well-documented animal model for studying HER2/neu-related breast cancer. It has been reported that a small percentage, approximately 20%, of the virgin female MMTV/neu mice seems resistant to the development of mammary gland adenoma, despite the overexpression of the neu oncogene.
To identify the factors that are responsible for the tumor resistance in these MMTV/neu female transgenic mice, comparative genetic profiling was used to screen the alterations in gene expression in the mammary gland. A novel gene named the RAS Association domain (RalGDS/AF-6) Family 3 (Rassf3), which belongs to a family of RAS effectors …