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Articles 1681 - 1710 of 8384

Full-Text Articles in Microbiology

Proposing An Rna Interference (Rnai)-Based Treatment For Human Immunodeficiency Virus (Hiv) By Analyzing The Post-Transcriptional Gene Targeting Of Sars-Cov-2, Hepatitis C Virus, And A549 Lung Cancer Cells, Arjun Jagdeesh Jan 2023

Proposing An Rna Interference (Rnai)-Based Treatment For Human Immunodeficiency Virus (Hiv) By Analyzing The Post-Transcriptional Gene Targeting Of Sars-Cov-2, Hepatitis C Virus, And A549 Lung Cancer Cells, Arjun Jagdeesh

Undergraduate Research Posters

Human Immunodeficiency Virus (HIV) is a retrovirus that infects CD4+ T cell lymphocytes in humans, leading to the development of Acquired Immunodeficiency Syndrome (AIDS) if left untreated. While current treatment methods, including antiretroviral combination treatments, effectively limit HIV replication, HIV can evade these treatments due to its high mutation rate. Long-term antiretroviral treatment can also be toxic to patients, meaning patients would benefit from a new mechanism of HIV treatment. RNA interference (RNAi) is an antiviral pathway found in mammals, plants, and insects that involves a small-interfering RNA that is incorporated into a protein complex called the RNA-induced Silencing Complex …

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Versican Provides The Provisional Matrix For Uterine Spiral Artery Dilation And Fetal Growth, Yusuke Sagae, Akihito Horie, Akihiro Yanai, Tsutomu Ohara, Baku Nakakita, Yoshimi Kitawaki, Asuka Okunomiya, Hirohiko Tani, Ken Yamaguchi, Junzo Hamanishi, John P Lydon, Takiko Daikoku, Hideto Watanabe, Masaki Mandai Jan 2023

Versican Provides The Provisional Matrix For Uterine Spiral Artery Dilation And Fetal Growth, Yusuke Sagae, Akihito Horie, Akihiro Yanai, Tsutomu Ohara, Baku Nakakita, Yoshimi Kitawaki, Asuka Okunomiya, Hirohiko Tani, Ken Yamaguchi, Junzo Hamanishi, John P Lydon, Takiko Daikoku, Hideto Watanabe, Masaki Mandai

Faculty, Staff and Students Publications

The extracellular matrix (ECM) in the endometrium plays a crucial role in mammalian pregnancy. We have shown that versican secreted from the endometrial epithelium promotes embryo implantation. Versican is a proteoglycan, a major player in the provisional matrix, and versikine, its N-terminal fragment cleaved by ADAMTS proteinases, serves as a bioactive molecule. Here, since versican expression in the placenta was dynamically altered in humans and mice, we investigated the role of versican in pregnancy using uterine-specific Vcan deletion mice (uKO mice) and ADAMTS-resistant versican expressing mice (V1R mice). uKO mice exhibited insufficient spiral artery dilation, followed by fetal growth restriction …

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Assessment Of The Cytolytic Potential Of A Multivirus-Targeted T Cell Therapy Using A Vital Dye-Based, Flow Cytometric Assay, Kiriakos Koukoulias, Penelope G Papayanni, Julia Jones, Manik Kuvalekar, Ayumi Watanabe, Yovana Velazquez, Sarah Gilmore, Anastasia Papadopoulou, Ann M Leen, Spyridoula Vasileiou Jan 2023

Assessment Of The Cytolytic Potential Of A Multivirus-Targeted T Cell Therapy Using A Vital Dye-Based, Flow Cytometric Assay, Kiriakos Koukoulias, Penelope G Papayanni, Julia Jones, Manik Kuvalekar, Ayumi Watanabe, Yovana Velazquez, Sarah Gilmore, Anastasia Papadopoulou, Ann M Leen, Spyridoula Vasileiou

Faculty, Staff and Students Publications

Reliable and sensitive characterization assays are important determinants of the successful clinical translation of immunotherapies. For the assessment of cytolytic potential, the chromium 51 (51Cr) release assay has long been considered the gold standard for testing effector cells. However, attaining the approvals to access and use radioactive isotopes is becoming increasingly complex, while technical aspects [i.e. sensitivity, short (4-6 hours) assay duration] may lead to suboptimal performance. This has been the case with our ex vivo expanded, polyclonal (CD4+ and CD8+) multivirus-specific T cell (multiVST) lines, which recognize 5 difficult-to-treat viruses [Adenovirus (AdV), BK virus (BKV), cytomegalovirus (CMV), Epstein Barr …

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Editorial: Health Effects And Pathophysiological Mechanisms Of One-Carbon Metabolism Nutrients Intake Throughout The Life Cycle, Jufen Liu, Yunping Lei, Lei Wang, Chao Guo Jan 2023

Editorial: Health Effects And Pathophysiological Mechanisms Of One-Carbon Metabolism Nutrients Intake Throughout The Life Cycle, Jufen Liu, Yunping Lei, Lei Wang, Chao Guo

Faculty, Staff and Students Publications

No abstract provided.

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The Rsv F P27 Peptide: Current Knowledge, Important Questions, Wanderson Rezende, Hadley E Neal, Rebecca E Dutch, Pedro A Piedra Jan 2023

The Rsv F P27 Peptide: Current Knowledge, Important Questions, Wanderson Rezende, Hadley E Neal, Rebecca E Dutch, Pedro A Piedra

Faculty, Staff and Students Publications

Respiratory syncytial virus (RSV) remains a leading cause of hospitalizations and death for young children and adults over 65. The worldwide impact of RSV has prioritized the search for an RSV vaccine, with most targeting the critical fusion (F) protein. However, questions remain about the mechanism of RSV entry and RSV F triggering and fusion promotion. This review highlights these questions, specifically those surrounding a cleaved 27 amino acids long peptide within F, p27.

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Diversity And Evolution Of Computationally Predicted T Cell Epitopes Against Human Respiratory Syncytial Virus, Jiani Chen, Swan Tan, Vasanthi Avadhanula, Leonard Moise, Pedro A Piedra, Anne S De Groot, Justin Bahl Jan 2023

Diversity And Evolution Of Computationally Predicted T Cell Epitopes Against Human Respiratory Syncytial Virus, Jiani Chen, Swan Tan, Vasanthi Avadhanula, Leonard Moise, Pedro A Piedra, Anne S De Groot, Justin Bahl

Faculty, Staff and Students Publications

Human respiratory syncytial virus (RSV) is a major cause of lower respiratory infection. Despite more than 60 years of research, there is no licensed vaccine. While B cell response is a major focus for vaccine design, the T cell epitope profile of RSV is also important for vaccine development. Here, we computationally predicted putative T cell epitopes in the Fusion protein (F) and Glycoprotein (G) of RSV wild circulating strains by predicting Major Histocompatibility Complex (MHC) class I and class II binding affinity. We limited our inferences to conserved epitopes in both F and G proteins that have been experimentally …

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Exploring The Microbial Composition Of Moonmilk In Wind Cave National Park, Emma Pellegrino Jan 2023

Exploring The Microbial Composition Of Moonmilk In Wind Cave National Park, Emma Pellegrino

Honors Program Theses

Moonmilk is a white substance mainly composed of calcium carbonate (CaCO3) that is often found in limestone caves. It is one of many mineral composites, or speleothems, in Wind Cave National Park South Dakota and is thought to be formed by microbial activity. This cave system is a complex, isolated environment that serves as an analog for similar domains beyond the Earth. Each site has varying degrees of human exposure, from public tour routes to caverns only occasionally visited by park rangers, making it an ideal place of study for pristine samples in extreme conditions. Wind Cave also varies in …

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Monitoring Archaeal Persistence In Cultivation, Payton Hall Jan 2023

Monitoring Archaeal Persistence In Cultivation, Payton Hall

Honors Program Theses

It was previously thought that microbes in the domain Archaea were only found in extreme environments such as hot thermal vents at the bottom of the ocean and hypersaline environments, but as scientists began to use environmental DNA to survey soil, they detected archaea from the phylum Thaumarchaeota in relatively benign environments including farm fields, forests, and prairies. In spite of their widespread global distribution, relatively few of these species have been grown in laboratory culture. It is now known that Thaumarchaeota play an important role in the nitrogen cycle because they can generate energy through ammonia-oxidation. To increase the …

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Evaluation Of Methods To Analyze Microbial Composition In Soils, Joseph Correa Jan 2023

Evaluation Of Methods To Analyze Microbial Composition In Soils, Joseph Correa

Honors Program Theses

DNA testing has become a vital tool for studying microbes in their natural environments, but there is a lack of standardization in the protocols for extracting environmental DNA. Cave systems provide a special and unique area to research how life thrives in extreme environments. Many parts of caves receive no sunlight and very little nutrients yet harbor microbial communities. Previous work in our lab developed a DNA extraction protocol that works with a wide range of microbial species and with different soil types. I updated this protocol by adding a pre-lysis rinse step and tested whether it performed better with …

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Sex-Dependent Effects Of Induced Acute Inflammation On Glucose Homeostasis And Rna Editing Enzymes, Christian A. Rivas Jan 2023

Sex-Dependent Effects Of Induced Acute Inflammation On Glucose Homeostasis And Rna Editing Enzymes, Christian A. Rivas

Graduate Theses/Dissertations

The first line of defense against bodily insults, like pathogen invasion, is the innate immune system. Innate immunity sets in motion countless cascades that result in inflammation. Inflammation simultaneously affects multiple biological processes like metabolism and gene expression. Males and females react differently to inflammation. To understand both molecular and physiological sex differences in inflammation, we examined how inflammation affects gene expression and glucose metabolism. Adenosine deaminase acting on RNA (ADAR1) is upregulated by inflammation and catalyzes RNA editing, a process where nucleotides encoded by the genome are modified. ADAR1 also controls the innate immune reaction by decreasing activity of …

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Distribution Patterns Of Allorhizobium Vitis In Missouri Vineyards And Non-Vineyard Soils, Jacquelyn M. Wray Jan 2023

Distribution Patterns Of Allorhizobium Vitis In Missouri Vineyards And Non-Vineyard Soils, Jacquelyn M. Wray

Graduate Theses/Dissertations

Crown gall disease causes significant economic loss to the grape and wine industry. Preventive strategies are most effective for mitigating the loss of grapevines in vineyards, as there is no known cure for this disease. The bacterium Allorhizobium vitis carrying a tumor-inducing (Ti) plasmid is the causative agent. A. vitis bacteria live systemically in the grapevine before causing visible symptoms and can survive in residual plant tissues and soil for more than two years. Diagnostic methods have been developed to detect A. vitis bacteria in grapevines and soil. However, more reliable, specific, and high-throughput diagnostics are still needed for screening …

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Investigation Of Bacterial Infection And Immunity In The Body Louse, Lauren Mae Kress Jan 2023

Investigation Of Bacterial Infection And Immunity In The Body Louse, Lauren Mae Kress

Dissertations and Theses

The human body louse (Pediculus humanus humanus) is a host-specific hematophagous ectoparasite that frequently infests populations experiencing a breakdown of hygienic conditions. Body lice are vectors for several bacterial human pathogens, including Borrelia recurrentis (relapsing fever), Rickettsia prowazekii (epidemic typhus) and Bartonella quintana (trench fever) (Badiaga & Brouqui 2012, Amanzougaghene et al. 2020). Today, louse-borne relapsing fever and epidemic typhus are largely geographically restricted to small foci in East Africa. However, B. quintana is a re-emerging and underappreciated pathogen throughout the globe, especially in urban environments (Mai 2022). Transmission of B. quintana is known to occur via inoculation of infectious …

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Survival Of Listeria Monocytogenes On Organic Honeycrisp And Fuji Apples During Storage At 5, 12 And 22.5◦C, Connor S. Freed Jan 2023

Survival Of Listeria Monocytogenes On Organic Honeycrisp And Fuji Apples During Storage At 5, 12 And 22.5◦C, Connor S. Freed

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study aimed to evaluate and model the survival of Listeria monocytogenes on organic HoneyCrisp (HC) and Fuji (FJ) apples during storage at various temperatures. Fresh organic HC and FJ apples (without wax coating) obtained from a local wholesale market were inoculated with a 2-strain mix of L. monocytogenes followed by storage at 5.0 (22.9% RH), 12.0 (37.0% RH), and 22.5oC (50.4% RH) for 60, 35, 7 days, respectively, and periodically (day-0 to 60) analyzing microbial populations. Surviving L. monocytogenes were spread-plated on Modified-Oxford agar after 10 or 100-fold serial dilution. Data were analyzed using the mixed-model procedure of SAS …

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Optimizing Sample Collection And Data Interpretation For Effective Wastewater-Based Epidemiology In Combined Sewer Systems, Christopher Allen Anderson Jan 2023

Optimizing Sample Collection And Data Interpretation For Effective Wastewater-Based Epidemiology In Combined Sewer Systems, Christopher Allen Anderson

Graduate Theses, Dissertations, and Problem Reports (ETD)

COVID-19 has spurred growth in the science surrounding wastewater-based epidemiology (WBE) pertaining to the detection of severe acute respiratory virus 2 (SARS-CoV-2) in waste streams as an early warning signal for public health. However, the highly variable wastewater environment has made it difficult to standardize an approach for sampling and analysis, especially in locations using combined sewer infrastructure. This study addresses knowledge gaps of WBE via three specific aims: (1) to compare diurnal fluctuations of SARS-CoV-2 and the human fecal indicator, pepper mild mottle virus (PMMoV) in wastewater treatment plant (WWTP) influent samples collected during dry versus wet weather conditions; …

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Evaluating Innovative Methods Of Quantitatively Linking Microbial Community Structure To Ecosystem Function, Jeth Gv Walkup Jan 2023

Evaluating Innovative Methods Of Quantitatively Linking Microbial Community Structure To Ecosystem Function, Jeth Gv Walkup

Graduate Theses, Dissertations, and Problem Reports (ETD)

Microbial functional diversity is the product of community structure and intraspecific trait variation. Due to microbial diversity and limited availability of microbial trait measurements, it has been challenging to quantitatively link community structure to microbial function. Although community-level activity rates vary with community composition, issues in the scale of their measurement inhibit our understanding of their relationship. Quantitative stable isotope probing (qSIP) is a method for quantitatively measuring taxon-specific microbial traits, providing new opportunities to apply trait-based approaches for studying microbial ecology. Quantitative microbial trait data from these experiments enables the functional characterization of microbial communities, potentially enabling the extrapolation …

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Comparing The Microbiomes Of Dental Plaques In 19th Century Ancestral Remains, Ananya Udyaver Jan 2023

Comparing The Microbiomes Of Dental Plaques In 19th Century Ancestral Remains, Ananya Udyaver

Undergraduate Research Posters

During the construction of VCU’s Hermes A. Kontos Medical Sciences Building in April 1994, nineteenth century ancestral remains were found in an abandoned well on the Medical College of Virginia (MCV) campus. This well, now known as the East Marshall Street Well (EMSW), is thought to have been used as a disposal location for cadaver dissection for surgical and other medical waste in the past. VCU is now seeking to use DNA sequencing technology to match and assemble bones from each individual for a proper burial, uncover the cultural and historical context in which these people lived, and bring a …

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Triclosan Degrading Bacteria From Wastewater Treatment Plants In Central Illinois, Mohammed Alsulami Jan 2023

Triclosan Degrading Bacteria From Wastewater Treatment Plants In Central Illinois, Mohammed Alsulami

Masters Theses

Triclosan is an antimicrobial agent that has been used in personal care products and has been identified to cause malformation on cartilage and bone development in zebrafish and influence on thyroid hormone system in humans. Due to its widespread usage and insufficient removal from wastewater treatment plants, triclosan has emerged as a pervasive contaminant that poses a potential threat to the environment and human health. The goal of the study was to isolate and characterize triclosan-degrading bacteria from WWTPs in central Illinois. Using enrichment culture with NMS media containing triclosan as sole carbon source, eighteen bacterial strains were isolated. The …

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Attachment Issues: Microbes, Minerals, And The Persistence Of Soil Organic Matter, Md Shafiul Islam Rion Jan 2023

Attachment Issues: Microbes, Minerals, And The Persistence Of Soil Organic Matter, Md Shafiul Islam Rion

Graduate Theses, Dissertations, and Problem Reports (ETD)

The remnants of microorganisms are now understood to account for the majority of organic matter in many mineral soils. Despite the significance of this microbial necromass for soil carbon storage, we know relatively little about how the traits of microorganisms interact with soil minerals to determine the stability of microbe derived carbon in soil. Soil minerals differ in their surface area and chemistry potentially influencing microbial attachment, biofilm formation, and the persistence of microbial necromass. To address this knowledge gap, we grew twelve bacterial species from four broad groups of varying cell wall morphology (Gram positive, Gram negative, filamentous actinobacteria, …

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Indigenous Toxin Affects Cell Viability, While An Artificial Proteolytic Queueing Causes The Upregulation Of Specific Genes, Mohammed Salahuddin Jan 2023

Indigenous Toxin Affects Cell Viability, While An Artificial Proteolytic Queueing Causes The Upregulation Of Specific Genes, Mohammed Salahuddin

Electronic Theses and Dissertations

Studying bacterial physiology is crucial to understand the fundamental mechanisms that govern bacterial growth, survival, and adaptation. This thesis combines two chapters investigating bacterial physiology by studying important cellular processes like bacterial toxin-antitoxin systems and proteolytic pathways. The first chapter involves studying bacterial toxin-antitoxin systems to understand the regulation and function of hypothetical toxin-antitoxin (TA) systems of bacteria and the effects of these TA systems on bacterial growth and survival. The emergence of these genetic modules in bacterial research and the unrevealing of some of their important roles in cell physiology in recent years has drawn much attention in scientific …

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Control Of Persistent Environmental Listeria Monocytogenes Using Phenotypic And Genomic Approaches, Bhaswati Chowdhury Jan 2023

Control Of Persistent Environmental Listeria Monocytogenes Using Phenotypic And Genomic Approaches, Bhaswati Chowdhury

Electronic Theses and Dissertations

No abstract provided.

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Laboratory Practices And Antimicrobial Resistance In A Florida Hospital, Crispina Marie Sy-Trias Jan 2023

Laboratory Practices And Antimicrobial Resistance In A Florida Hospital, Crispina Marie Sy-Trias

Walden Dissertations and Doctoral Studies

Antibiotic resistance is a health threat affecting millions of Americans. Microorganisms develop resistance to antibiotics, rendering them useless for treating infections. The purpose of this quantitative study was to assess the associations between sample processing time and antibiotic resistance and is based on the health belief model. A retrospective specimen tracking activity of data from November 2019 to November 2020 was obtained by random sampling of 246 bacterial cultures. One hundred ninety-six (80%) samples were processed on time, and 50 (20%) were delayed; 167 (68%) samples were determined to have the presence of antimicrobial resistance (AMR), and 79 (32%) with …

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Effects Of Altering Physiologically Relevant Cholesterol Levels And Media Types On Porin Gene Expression In Klebsiella Pneumoniae And The Resulting Impact On Antibiotic Resistance, Megan R. Camden Jan 2023

Effects Of Altering Physiologically Relevant Cholesterol Levels And Media Types On Porin Gene Expression In Klebsiella Pneumoniae And The Resulting Impact On Antibiotic Resistance, Megan R. Camden

UNF Graduate Theses and Dissertations

Klebsiella pneumoniae is a Gram-negative, non-motile bacterium belonging to the Enterobacteriaceae family. K. pneumoniae is a rising threat in the clinical setting, as there has been a large increase in the presence of antibiotic resistant isolates. While much research is conducted on laboratory and clinical strains of bacteria, not much is known regarding the impact that human physiology can have on bacterial gene expression, and in response, to antibiotic susceptibility. The goal of this study is to determine if physiologically relevant cholesterol levels and media types impact porin gene expression and antibiotic resistance in K. pneumoniae. To accomplish this, …

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Confocal Analysis Of Sindbis Virus In Aedes Aegypti Unveils Novel Infection Site At Pyloric Armature, Katie Gillian Peters Jan 2023

Confocal Analysis Of Sindbis Virus In Aedes Aegypti Unveils Novel Infection Site At Pyloric Armature, Katie Gillian Peters

UNF Graduate Theses and Dissertations

Arthropod-borne viruses (arboviruses), such as Sindbis virus (SINV), generate foci of infection within the midgut of viremic blood-fed mosquitoes. Arboviruses can disseminate out of the midgut into the surrounding musculature and hemolymph, eventually making it to the salivary glands where virus can be transmitted by saliva during a subsequent blood-feed. In this study, the virus SINV containing the reporter gene GFP, combined with immunohistochemistry, was imaged using confocal microscopy and used to evaluate the infection within the vector mosquito Aedes aegypti. The spatial distribution of SINV infection revealed two common characteristics of foci generated in the midgut. (1) There …

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Microbial Communities In The Guana Tolomato Matanzas National Estuarine Research Reserve: An Assessment Of The Responses Of Spartina Alterniflora Epiphytes To Nitrogen Enrichment, And A Characterization Of Benthic Cyanobacterial Diversity, Anne C. Hurley Jan 2023

Microbial Communities In The Guana Tolomato Matanzas National Estuarine Research Reserve: An Assessment Of The Responses Of Spartina Alterniflora Epiphytes To Nitrogen Enrichment, And A Characterization Of Benthic Cyanobacterial Diversity, Anne C. Hurley

UNF Graduate Theses and Dissertations

Elevated nitrogen and phosphorus inputs from anthropogenic sources, which can lead to significant increases in algal biomass and changes in algal community composition, poses a serious threat to estuarine ecosystems worldwide. While numerous studies have addressed the impacts of nutrient enrichment on epiphytic algae in seagrass habitats, few have investigated potential nutrient-driven changes to epiphytes on emergent salt marsh plants, such as Spartina alterniflora. Epiphytic microalgae on S. alterniflora play an important role in food availability in salt marsh ecosystems, and epiphytic nitrogen-fixing cyanobacteria also provide an important source of nitrogen for salt marsh consumers. The first study included …

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Elucidating The Role Of A Staphylococcal Glucosaminidase In Host Innate Immune Responses, Zachary Resko Jan 2023

Elucidating The Role Of A Staphylococcal Glucosaminidase In Host Innate Immune Responses, Zachary Resko

Dissertations

The peptidoglycan of Staphylococcus aureus is a critical cell envelope constituent and virulence factor that subverts host immune defenses and provides protection against environmental stressors. Peptidoglycan chains of the S. aureus cell wall are processed to characteristically short lengths by the glucosaminidase, SagB. It is well established that peptidoglycan is an important pathogen-associated molecular pattern (PAMP) that is recognized by the host innate immune system and promotes production of pro-inflammatory cytokines, including IL-1β. However, how bacterial processing of peptidoglycan drives IL-1β production is comparatively unexplored. Here, we tested the involvement of staphylococcal glucosaminidases in shaping innate immune responses and identified …

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Identification Of Conditions That Promote Biofilm Formation By Vibrio Fischeri And Elucidation Of The Underlying Signal Transduction Pathway, Courtney Noelle Dial Jan 2023

Identification Of Conditions That Promote Biofilm Formation By Vibrio Fischeri And Elucidation Of The Underlying Signal Transduction Pathway, Courtney Noelle Dial

Dissertations

Biofilms are communities of microorganisms that have intrinsically antimicrobial properties and are difficult to treat in the clinical setting. The marine bacterium Vibrio fischeri efficiently colonizes its symbiotic squid host, Euprymna scolopes, by producing a transient biofilm dependent on the symbiosis polysaccharide (SYP), making it the perfect model system to study biofilm dynamics. In vitro, however, wild-type (WT) strain ES114 fails to form SYP – dependent biofilms. Instead, genetically engineered strains, such as those lacking the negative regulator BinK, have been developed to study SYP biofilms. Historically, V. fischeri has been grown using LBS, a complex medium containing tryptone and …

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Characterization Of Mroq-Dependent Regulation Of Staphylococcus Aureus Quorum Sensing, Madison Ruth Stock Jan 2023

Characterization Of Mroq-Dependent Regulation Of Staphylococcus Aureus Quorum Sensing, Madison Ruth Stock

Dissertations

Gram-positive bacteria produce small autoinducing peptides (AIPs), which act to regulate expression of genes that promote adaptive traits including virulence. The Gram-positive pathogen Staphylococcus aureus generates a cyclic AIP that controls expression of virulence factors via the accessory gene regulatory (Agr) system. S. aureus strains belong to one of four Agr groups (I, II, III, and IV), and each group harbors allelic variants of AgrD, the precursor of AIP. In a prior screen for S. aureus virulence factors, the Alonzo lab identified MroQ, a putative peptidase. A ΔmroQ mutant closely resembled a Δagr mutant and had significant defects in AIP …

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Investigating Putative Toxin-Immunity Pairs From A New Class Of Rhs Proteins In Pseudomonas Aeruginosa, Syed Faieq Imam Jan 2023

Investigating Putative Toxin-Immunity Pairs From A New Class Of Rhs Proteins In Pseudomonas Aeruginosa, Syed Faieq Imam

Master's Theses

Pseudomonas aeruginosa is a gram-negative, opportunistic pathogen that is ubiquitous in nature, especially in human/animal impacted environments. One of the reasons for this is the arsenal of protein systems and toxins that P. aeruginosa utilizes to mold its environment to suit its needs. Recently, we discovered a novel locus in the P. aeruginosa genome, which resembles other loci that are known to mediate interbacterial competition. Our bioinformatic analysis found this locus to be enriched in a rearrangement hotspot (rhs) motif which led us to ad-interim term the three ORFs of the loci as rhsB, rhsC, and rhsI. Furthermore, we have …

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Investigating Structural And Biochemical Characteristics Of A Peptidase Required For Staphylococcus Aureus Virulence, Sagar Bhusal Jan 2023

Investigating Structural And Biochemical Characteristics Of A Peptidase Required For Staphylococcus Aureus Virulence, Sagar Bhusal

Master's Theses

Staphylococcus aureus is an opportunistic Gram-positive pathogen that transiently colonizes 30% of the population at any given time. Upon breaching host skin or mucosal barriers, S. aureus can infect and cause disease in nearly all host tissues. Once inside the host, S. aureus expresses a plethora of virulence factors, mostly regulated by the Accessory Gene Regulatory (Agr) quorum sensing system, which facilitates the evasion of immune responses or directly promotes pathogenesis. The S. aureus Agr system relies on the production of a small peptide known as an auto-inducing peptide (AIP) to control virulence gene expression in response to cell density. …

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Identification Of New Substrates From Pseudomonas Aeruginosa Exos, Adam V. Thota Jan 2023

Identification Of New Substrates From Pseudomonas Aeruginosa Exos, Adam V. Thota

Master's Theses

Pseudomonas aeruginosa is a gram-negative environmental bacterium that uses its intrinsic and acquired antibiotic resistance to infect patients with compromised epithelium, such as cystic fibrosis and burn wounds, and corneal keratitis. In order to cause disease, most strains of P. aeruginosa use the type three secretion system (T3SS) to disrupt cellular signaling and integrity. However, P. aeruginosa may also secrete exotoxins after invading host cells, which prolongs host cell death and maintains an intracellular niche. Of the T3 secreted effector toxins, ExoS, specifically the ADP-ribosyltransferase activity of ExoS, was shown to delay the death of invaded corneal cells, but it …

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