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Pertussis Resurgence In Europe: Incidence And Epidemiologic Cycles In Immunization Required And Non-Required Countries, Sheryl Ann Duquet Jan 2020

Pertussis Resurgence In Europe: Incidence And Epidemiologic Cycles In Immunization Required And Non-Required Countries, Sheryl Ann Duquet

Walden Dissertations and Doctoral Studies

Although pertussis vaccines have been available for over 7 decades, countries are experiencing a pertussis resurgence. This study sought to establish a relationship between the European pertussis immunization schedule designs (with and without the inclusion of adolescent boosters) and the immunization requirement (recommended or required), which potentially influences immunity waning, and thus the incidence rate and epidemiologic cycles of pertussis. The theoretical foundation for this study was the theory of herd immunity. A quantitative research method was used, supported by a secondary data source. The statistical analysis included the use of linear regression to evaluate the relationship between the requirement ...


Genetic Analysis Of A Novel Ftsk Homolog, Hfka, In Streptomyces Coelicolor Development-Associated Chromosome Segregation, Sumedha Sethi Dec 2019

Genetic Analysis Of A Novel Ftsk Homolog, Hfka, In Streptomyces Coelicolor Development-Associated Chromosome Segregation, Sumedha Sethi

Electronic Theses and Dissertations

A quintessential phenomenon occurring during prokaryotic development is accurate segregation of the replicated genomes into the daughter cells. Key energy-dependent processes like chromosome condensation and subcellular partitioning of the genomes are driven by conserved proteins like SMC, ParB, FtsK. During its complex developmental cycle, Streptomyces coelicolor segregates its genomes into chains of unicellular spores when its multigenomic syncytial aerial hyphae undergo division.

A novel ftsK-like gene, hfkA (Homolog of FtsK protein A), was examined for function and localization during development-associated chromosome segregation. Individual deletions did not affect segregation, but a ΔhfkA ΔftsK mutant exhibited 8% anucleate spores ...


A Possible Luxr Solo Type Regulator Of An Antibiotic-Like Compound From The Soil Bacterium Rhodococcus, Katelyn Sellick Dec 2019

A Possible Luxr Solo Type Regulator Of An Antibiotic-Like Compound From The Soil Bacterium Rhodococcus, Katelyn Sellick

Electronic Theses and Dissertations

Rhodococcus, a species of bacteria commonly found in the soil, is an under-explored producer of small bioactive compounds including siderophores, pigments and antibiotics. MTM3W5.2 is a strain of Rhodococcus that was previously discovered to produce an antibiotic-like compound that has inhibitory effects on other Rhodococcus strains, including the veterinary pathogen, R. equi. The biosynthetic gene cluster responsible for production of the antibiotic has been identified, and a small gene, BTZ20_3964 at the start of the operon is believed to be a luxR solo regulator of the gene cluster. The goal of this project was to determine this gene’s ...


Cellular And Viral Determinants Of Hsv-1 Entry And Transport, Farhana Musarrat Nov 2019

Cellular And Viral Determinants Of Hsv-1 Entry And Transport, Farhana Musarrat

LSU Doctoral Dissertations

Previously, it was shown that the deletion of 38 amino acids from the N terminal end of glycoprotein K (gK) prevents the Herpes Simplex virus Type-1 (HSV-1McKrae ∆gK31-68) from entering into the axons of neurons. Herein, we showed for the first time that this modification in gK disrupts the ability of the virus to carry out a fusion of the viral envelope with the cellular plasma membrane and forces the virus to enter via endocytosis in epithelial cells and neuronal cell bodies. We showed that HSV-1 McKrae infection triggers cellular calcium signaling, Akt activation, and flipping of Akt to the ...


The Effect Of Historic Shipwrecks On Sediment Microbiomes In The Northern Gulf Of Mexico, Melissa Brock Oct 2019

The Effect Of Historic Shipwrecks On Sediment Microbiomes In The Northern Gulf Of Mexico, Melissa Brock

Master's Theses

Microorganisms are ubiquitously distributed across all aquatic habitats, but it is the environmental conditions of a habitat that determine which microorganisms can thrive in terms of abundance or metabolic activity. Habitats that experience consistent physical and chemical environmental conditions repeatedly favor specific taxonomic groups which may result in a microbial assemblage that is commonly associated with that habitat (i.e., a core microbiome). Core microbiomes have been identified for a variety of natural marine habitats including methane seeps, wood falls, octocoral, and deep-sea sediments. However, it was unknown if the presence of man-made structures on the seafloor, including historic shipwrecks ...


Tungsten Is Essential For Long-Term Maintenance Of Members Of Candidate Archaeal Genus Aigarchaeota Group 4, Joshua Robert Reyes Dimapilis Sep 2019

Tungsten Is Essential For Long-Term Maintenance Of Members Of Candidate Archaeal Genus Aigarchaeota Group 4, Joshua Robert Reyes Dimapilis

Electronic Theses, Projects, and Dissertations

Aigarchaeota, a deeply branching archaeal lineage with no cultivated representatives, is found in geothermal and hydrothermal systems worldwide and consists of at least 9 genus-level groups, each predicted to have diverse metabolic capabilities. This candidate archaeal phylum is part of the TACK superphylum, members of which possess eukaryotic-signature proteins, thus suggesting that they may represent evolutionary steps along the way to the genesis of the first eukaryotic cells. Cultivating members of Aigarchaeota would elucidate how eukaryotes arose in evolutionary history and provide biotechnological applications. Aigarchaeota Group 4 (AigG4), one genus in Aigarchaeota, was previously found to be abundant in corn ...


Isolation Of Caldatribacterium (Op9) And Investigation Of Its Potential Interactions With A Novel, Co-Cultivated Thermodesulfobacterium Species, Toshio Alvarado Sep 2019

Isolation Of Caldatribacterium (Op9) And Investigation Of Its Potential Interactions With A Novel, Co-Cultivated Thermodesulfobacterium Species, Toshio Alvarado

Electronic Theses, Projects, and Dissertations

Atribacteria (OP9), candidate phylum with no representatives in pure culture, is found in various anaerobic environments worldwide. “Caldatribacterium”, a lineage within Atribacteria that is predicted to be a strictly anaerobic sugar fermenter based on cultivation-independent genomic analyses, is currently being maintained in lab enrichment cultures with fucose as its sole growth substrate. Metagenomics and 16S rRNA gene tag sequencing indicated that the fucose culture was a co-culture of “Caldatribacterium” and an uncultivated member of the genus Thermodesulfobacterium. Due to failed attempts to isolate “Caldatribacterium” by dilution-to-extinction and plating, it was hypothesized that “Caldatribacterium” is dependent in some way on the ...


Using Single-Cell Sorting, Fish And 13c-Labeling To Cultivate And Assess Carbon Substrate Utilization Of ‘Aigarchaeota’ And Other Novel Thermophiles, Damon Kurtis Mosier Sep 2019

Using Single-Cell Sorting, Fish And 13c-Labeling To Cultivate And Assess Carbon Substrate Utilization Of ‘Aigarchaeota’ And Other Novel Thermophiles, Damon Kurtis Mosier

Electronic Theses, Projects, and Dissertations

‘Aigarchaeota’, a deeply branching lineage in the domain Archaea with no cultivated representatives, includes both thermophilic and hyperthermophilic microorganisms that reside in terrestrial and marine geothermal environments. The ‘Aigarchaeota’ consists of at least nine proposed genus-level groups that have been confirmed via 16S rRNA sequencing, with ‘Aigarchaeota’ Group 1 (AigG1) being the focus of this study. Based on cultivation-independent genomic data available from several AigG1 members in Great Boiling Spring (GBS), NV, and Yellowstone National Park, 22 different types of growth media were designed and tested for their ability to support growth of AigG1. One of these cultures, G1-10, was ...


Intravital Imaging In A Zebrafish Model Elucidates Interactions Between Mucosal Immunity And Pathogenic Fungi, Linda S. Archambault Aug 2019

Intravital Imaging In A Zebrafish Model Elucidates Interactions Between Mucosal Immunity And Pathogenic Fungi, Linda S. Archambault

Electronic Theses and Dissertations

Candida yeasts are common commensals that can cause mucosal disease and life-threatening systemic infections. While many of the components required for defense against Candida albicans infection are well established, questions remain about how various host cells at mucosal sites assess threats and coordinate defenses to prevent normally commensal organisms from becoming pathogenic. Using two Candida species, C. albicans and C. parapsilosis, which differ in their abilities to damage epithelial tissues, we used traditional methods (pathogen CFU, host survival, and host cytokine expression) combined with high-resolution intravital imaging of transparent zebrafish larvae to illuminate host-pathogen interactions at the cellular level in ...


Design And Implementation Of Degenerate Qpcr/Qrt-Pcr Primers To Detect Microbial Nitrogen Metabolism In Wastewater And Wastewater-Related Samples, Ryan F. Keeley Aug 2019

Design And Implementation Of Degenerate Qpcr/Qrt-Pcr Primers To Detect Microbial Nitrogen Metabolism In Wastewater And Wastewater-Related Samples, Ryan F. Keeley

Graduate Theses and Dissertations

Nitrogen cycling processes can be tracked using quantitative Polymerase Chain Reaction (qPCR) to determine the presence and qReverse Transcriptase-PCR (qRT-PCR) to determine expression of key genes, or ‘biological markers’, for nitrogen metabolism. Nitrification is catalyzed in part, by two enzymes: ammonia monooxygenase (AMO; NH3 NH2OH) and nitrite oxidoreductase (NXR; NO2- NO3-). For denitrification, four enzymes act sequentially: nitrate reductase (NAR/NAP; NO3- NO2-), nitrite reductase (NIR; NO2- NO), nitric oxide reductase (NOR; NO  N2O), and nitrous oxide reductase (NOS; N2O  N2). A principle of wastewater treatment (WWT) is to remove excess nitrogen by taking advantage of natural nitrogen cycling or ...


Secretory Iga Enhances Gut B Cells Priming And Systemic Igg Responses Towards Commensals, You Zhou Aug 2019

Secretory Iga Enhances Gut B Cells Priming And Systemic Igg Responses Towards Commensals, You Zhou

Arts & Sciences Electronic Theses and Dissertations

IgA is the primary antibody response at mucosal surfaces and is reported to inhibit adaptive immune responses against gut bacteria. Here, we utilize an in vitro system to expand and screen IgA memory B cells for their ability to recognize gut bacteria in the context of secretory IgA (sIgA) deficiency in polymeric Ig receptor (Pigr–/–) mice. Contrary to the prevailing hypothesis that IgA provides an immune exclusionary function, we found that mice lacking sIgA showed decreased anti-bacterial IgA specificities as assessed using flow cytometry. IgA B cell responses against certain taxa such as those of order Bacteriodales showed greater dependence ...


Flavobacterium Gliding Motility: From Protein Secretion To Cell Surface Adhesin Movements, Joseph Johnston Aug 2019

Flavobacterium Gliding Motility: From Protein Secretion To Cell Surface Adhesin Movements, Joseph Johnston

Theses and Dissertations

Flavobacterium johnsoniae exhibits rapid gliding motility over surfaces. At least twenty genes are involved in this process. Seven of these, gldK, gldL, gldM, gldN, sprA, sprE, and sprT encode proteins of the type IX protein secretion system (T9SS). The T9SS is required for surface localization of the motility adhesins SprB and RemA, and for secretion of the soluble chitinase ChiA. This thesis demonstrates that the gliding motility proteins GldA, GldB, GldD, GldF, GldH, GldI and GldJ are also essential for secretion. Cells with mutations in the genes encoding any of these seven proteins had normal levels of gldK mRNA but ...


Properties Of Hiv-1 Env And Human Seminal Fluid That Determine Virus Inhibition By Antibodies And Microbicides, Jacklyn Johnson Aug 2019

Properties Of Hiv-1 Env And Human Seminal Fluid That Determine Virus Inhibition By Antibodies And Microbicides, Jacklyn Johnson

Theses and Dissertations

Human immunodeficiency virus type 1 (HIV-1) establishes a persistent infection that leads to acquired immunodeficiency syndrome (AIDS). Approximately 36 million people worldwide are living with HIV-1, which is commonly acquired through sexual contact. Antiviral therapies control disease progression, but do not eliminate this virus from the host. Thus, global efforts are focused on developing vaccines that prevent HIV-1 transmission. Such vaccines are based on eliciting the production of protective antibodies that target the envelope glycoproteins (Envs) of this virus. Unfortunately, HIV-1 immunization trials have shown limited efficacy. A better understanding of the antibody-mediated inactivation process is needed to improve vaccine ...


Investigation Of Microbiota In Health And Disease Of Poultry, Bishnu Adhikari Aug 2019

Investigation Of Microbiota In Health And Disease Of Poultry, Bishnu Adhikari

Theses and Dissertations

The microbiotas play vital roles in health and diseases of both humans and animals. 16S rRNA genes sequence analysis is one of the most popular and commonly used methods in the analysis of microbiotas associated with hosts. In this dissertation, the microbiotas of chickens (broilers, breeders, and layers) and turkeys were evaluated by 16S rRNA gene sequencing. Characterization of the culturable subpopulations of Lactobacillus in the chicken gut can serve as a valuable resource for probiotic development. In Chapter 2, Lactobacillus subpopulations recovered on MRS from chicken gut were defined comprehensively for the first time using 16S rRNA gene profiling ...


16s Rrna Analysis And Toxin Gene Presence In Escherichia Coli Isolated From Beach Water And Sand At A Public Beach (Erie County, Ny), Jennifer D. Jackson Aug 2019

16s Rrna Analysis And Toxin Gene Presence In Escherichia Coli Isolated From Beach Water And Sand At A Public Beach (Erie County, Ny), Jennifer D. Jackson

Biology Theses

Every year, thousands of people utilize beaches for recreation, but most are unaware of Escherichia coli (E. coli) contamination and the possibility of acquiring an infection. In this study, 173 strains of E. coli were isolated from sand and adjacent waters from a public beach in Erie County, NY and analyzed for genetic relatedness based on sequence differences in the variable regions of the 16S rRNA gene. Some of the variable regions (V1 and V6) proved useful in constructing phylogenetic trees but the discriminatory power of these regions was inadequate to resolve intraspecies differences. Therefore, whether extant populations of E ...


Characterizing Nodule Endophyte Communities In Glycine Max And Lablab Purpureus Using Next-Generation Sequencing, Scott David Mcelveen Aug 2019

Characterizing Nodule Endophyte Communities In Glycine Max And Lablab Purpureus Using Next-Generation Sequencing, Scott David Mcelveen

MSU Graduate Theses

Biological nitrogen fixation by rhizobia in the root nodules of legumes is a significant source of agricultural nitrogen in global crop production systems. The influence of and interaction of factors involved in nodule endophyte selection remain poorly understood. In the present study, the influences of crop rotation (soybean-legume vs. cotton-legume) and recalcitrant soil organic matter (compost amendment) on the relative distribution of endophytic bacteria in the root nodules of greenhouse-grown soybean and lablab were investigated by extracting, amplifying, and sequencing 16S ribosomal RNA (rRNA) and nifH genes. Neither preceding crop nor compost amendment were found to have an influence on ...


Intratypic Genetic Variability Of Human Adenovirus Type 4: Implication For Viral Pathogenesis, Camden Roy Bair Jul 2019

Intratypic Genetic Variability Of Human Adenovirus Type 4: Implication For Viral Pathogenesis, Camden Roy Bair

Biomedical Sciences ETDs

Human adenovirus type 4 (HAdV-E4) is a causative agent of acute respiratory disease and conjunctivitis worldwide. Two major lineages of HAdV-E4 genomic variants have been identified by their distinct BamHI restriction profiles: prototype-like (p-like) strains and the a-like genomic variants. Recent molecular epidemiology studies have shown a predominance of a-like genomic variants detected in association with disease which suggests a-like strains have a fitness advantage or they may be more pathogenic. The impact of HAdV-E4 intratypic genetic variability on in vitro and in vivo phenotypes relevant to pathogenesis is a major gap in knowledge. I hypothesize that HAdV-E4 comprises two ...


A Small Rna And Dna Binding Protein Contribute To Biofilm Development In Bartonella Henselae, Udoka Okaro Jul 2019

A Small Rna And Dna Binding Protein Contribute To Biofilm Development In Bartonella Henselae, Udoka Okaro

Graduate Theses and Dissertations

A biofilm, which is associated with 80% of chronic infections in humans, is formed when bacteria aggregate, attach to a substrate and secrete a matrix protecting the bacteria from host cell defenses and antibiotics. Bartonella henselae (B. henselae) is the causative agent of cat scratch disease, persistent bacteremia, and one of the most frequently reported causes of blood-culture negative endocarditis (BCNE) in patients. The ability of B. henselae to adhere to the heart valve, form a biofilm and vegetation to cause endocarditis increases the morbidity and mortality rate in infected patients. The presence of a trimeric autotransporter adhesin (TAA) called ...


Development Of A Prolyl Endopeptidase Expression System In Lactobacillus Reuteri To Reduce The Clinical Manifestation Of Celiac Disease, Kara Lynn Jew Jul 2019

Development Of A Prolyl Endopeptidase Expression System In Lactobacillus Reuteri To Reduce The Clinical Manifestation Of Celiac Disease, Kara Lynn Jew

Master's Theses and Project Reports

Celiac Disease (CD) is an autoimmune disorder that emerges due to the ingestion of gluten, a protein found in a variety of common grains such as wheat, rye, and barley. Approximately 1 in 100 individuals in the US suffer from CD, making it the most commonly diagnosed gastrointestinal disorder (Ciclitira et. al., 2005). These proline-rich gluten peptides are resistant to proteolysis and accumulate in the duodenum of the small intestine. Once in the duodenum, these peptides illicit an autoimmune response resulting in villous atrophy. Current treatment for CD requires a rigorous adherence to a gluten-free diet. Nevertheless, gluten-containing grains are ...


Iron-Sulfur Cluster Biosynthesis In Methanogens, Cuiping Zhao Jun 2019

Iron-Sulfur Cluster Biosynthesis In Methanogens, Cuiping Zhao

LSU Doctoral Dissertations

Methanogens live in a syntrophic consortium with bacteria, taking advantage of the metabolic abilities of their syntrophic partners to overcome energetic barriers and break down compounds that they cannot digest by themselves. Interspecies electron transfer, which is a major type of microbial communication in syntrophic processes, improves methanogenesis and anaerobic oxidization of methane (AOM) processes involved in syntrophic consortia. These processes have a significant impact on the global carbon cycle. Most of the essential enzymes involved in methanogenesis are iron-sulfur proteins. Iron-sulfur clusters are one of the oldest and most versatile cofactors present in all domains of life. To date ...


Study Of Paper Microbial Fuel Cells For Use In On-Site Wastewater Testing, William A. Tolmasoff Jun 2019

Study Of Paper Microbial Fuel Cells For Use In On-Site Wastewater Testing, William A. Tolmasoff

Master's Theses and Project Reports

This study demonstrated a technique for fabricating simple, low-cost Paper Microbial fuel cells (PMFC’s) in the model of a previous study to, for the first time, produce voltage from wastewater effluent. The PMFC’s were created by stacking and gluing the main components of an MFC together: reservoir layer; anode; cation exchange membrane (CEM); air cathode. A wax printer was used to create the hydrophobic borders of the PMFC’s on filter paper, and graphite paint was applied to the paper to create the anode. The CEM’s considered were filter paper, wax, and Nafion, with Nafion being the ...


New Periodontal Pathogens And Their Biogeography In Ex Vivo Biofilms, Fany B. Ocampo May 2019

New Periodontal Pathogens And Their Biogeography In Ex Vivo Biofilms, Fany B. Ocampo

Dental Theses

Background: About 35% of the oral microbiome remains uncultured due to limitations of conventional laboratory techniques. More than 200 of those phylotypes have been catalogued in the HOMD and a subset of them had been proposed as candidate periodontal pathogens. This segment of the microbiome merits further investigation, as it might harbor important pathogens that are currently overlooked. Objective: The objective of this study was to devise an imaging approach to study such phylotypes in the conditions most conducive to their growth and begin to unveil their ecological and biogeographical characteristics.

Methods: Previous work from the Teles Lab had identified ...


Stalking Flu: Development And Characterization Of A Broadly Neutralizing Monoclonal Antibody Targeting The Influenza Hemagglutinin Stem, Elizabeth Newman May 2019

Stalking Flu: Development And Characterization Of A Broadly Neutralizing Monoclonal Antibody Targeting The Influenza Hemagglutinin Stem, Elizabeth Newman

NYMC Student Theses and Dissertations

Seasonal epidemics caused by influenza A viruses (IAV) result in an estimated 290,000- 650,000 deaths worldwide each year (17). While antivirals targeted to influenza exist, resistance to these drugs is increasing and regular vaccination remains the most effective way to prevent infection (26, 73, 99). However due to the persistence of antigenic drift and shift, influenza vaccines must be updated each season and antigenic mismatches can reduce efficacy (24, 118). Immunity to influenza either from vaccination or infection is principally mediated by antibodies generated to one of its major surface proteins, Hemagglutinin (HA). HA is a homotrimer, each ...


Kinetics Of Hiv-1 Uncoating In C20 Microglial Cells, Melanie Anne Taylor May 2019

Kinetics Of Hiv-1 Uncoating In C20 Microglial Cells, Melanie Anne Taylor

MSU Graduate Theses

Uncoating is a poorly understood yet required step of HIV-1 replication that is defined as the disassembly of the viral capsid structure. The goal of this project is to characterize uncoating in C20 microglial cells. These cells are a natural target of HIV-1 that are infected to establish latent viral reservoirs and HIV-associated neurological disorders. A stable C20 cell line that expresses TRIM-CypA was established to study the kinetics of uncoating with the CsA washout assay. The expression of TRIM-CypA was confirmed by western blot and the functionality of the protein was confirmed by a viral infectivity assay. Using this ...


Investigation Of Origin And Growth Of Fungi In Coastal Beach Sand, Ruth L. Wright May 2019

Investigation Of Origin And Growth Of Fungi In Coastal Beach Sand, Ruth L. Wright

Honors Theses

In a previous study from this lab (Stevens, Evans, & Aguirre, 2012) yeast colonies were isolated and grown grown from sand collection at pristine, medium use and high use beaches along the grand strand. In that study greater yeast abundance and greater diversity both correlated with higher census of human use, suggesting that some yeast growth of sites was anthropogenic. However the sand matrix itself also varied from very fine, uniform, dark sand at the pristine beach to coarser, color varying, less tightly packed sand at residential and commercial beaches. This suggested an alternative hypothesis to differential colonization and growth depending ...


Fungi In A Hot, Dry, Changing World, Miriam I. Hutchinson May 2019

Fungi In A Hot, Dry, Changing World, Miriam I. Hutchinson

Biology ETDs

My doctoral work focused on understanding the reciprocal relationship between fungi and their environment, namely how fungi respond to environmental flux, as well as how fungi can modify and structure their habitats, especially in the context of climate change. As such, I aimed my research on fungi with distinct adaptations to their environmental niches: endophytic fungi that inhabit plant tissue and thermophilic fungi that are capable of growing at the upper temperature limit for eukaryotic life. My research consisted of three studies. First, I investigated the thermophilic species Myceliophthora heterothallica to demonstrate its use as a model organism for efficient ...


Effects Of Temperature On Microbial Parameters Associated With Decaying Plant Litter In A Stream Microcosm Experiment, Hunter David Pates May 2019

Effects Of Temperature On Microbial Parameters Associated With Decaying Plant Litter In A Stream Microcosm Experiment, Hunter David Pates

Electronic Theses and Dissertations

Increases in mean surface air temperature under climate-change predictions are expected to affect microbial activity, as well as carbon dynamics in aquatic ecosystems. I explored responses of litter-associated decomposers along temperature ranges typical of temperate streams in laboratory microcosms simulating stream conditions. The objectives of this study were to determine (1) whether the effects of temperature on stream leaf-associated microorganisms can be explained by the Metabolic Theory of Ecology (MTE); (2) if the effects of temperature are the same across temperatures commonly found in temperate streams; and (3) if there are differences in the magnitude of responses to temperature among ...


The Importance Of Rnd-Type Efflux Pumps In The Interactions Of Pseudomonas Aeruginosa With 4-Methoxybenzaldehyde, Sanchirmaa Namjilsuren May 2019

The Importance Of Rnd-Type Efflux Pumps In The Interactions Of Pseudomonas Aeruginosa With 4-Methoxybenzaldehyde, Sanchirmaa Namjilsuren

Honors Theses

Pseudomonas aeruginosa is a common hospital-acquired pathogen and is often associated with high mortality rates due to the development of multidrug-resistance. Antimicrobial plant-derived (phyto-) aldehydes present a promising alternative to antibiotics due to their broad-spectrum antimicrobial activity and low propensity to trigger resistance. However, two main problems preclude the widespread application of these compounds: chemical instability and low antimicrobial efficacy. The ongoing collaboration between the Mavrodi and Patton labs at USM has recently addressed the problem of chemical instability by incorporating plant aldehydes into polymer materials called Pro-Antimicrobial Networks via Degradable Acetals (PANDAs). Thus, this study aimed to address the ...


The Effect Of Stenotrophomonas Maltophilia On Gram-Negative Cystic Fibrosis Pathogens., Joshua D Stewart May 2019

The Effect Of Stenotrophomonas Maltophilia On Gram-Negative Cystic Fibrosis Pathogens., Joshua D Stewart

College of Arts & Sciences Senior Honors Theses

Cystic Fibrosis (CF) is the most common lethal genetic disorder in the Caucasian population with an incidence of 1 per 3,000 live births and a median predicted survival of only 47 years. Respiratory failure due to repeated pathological insults to lung tissue by infection is the ultimate cause of mortality in the majority of patients. The lung microenvironment created by CF highly favors colonization by opportunistic pathogens such as Pseudomonas aeruginosa, Stenotrophomonas maltophilia, Burkholderia cenocepacia, and Achromobacter xylosoxidans. Biofilm formation by multiple bacterial species contributes to the chronic, persistent, and difficult to treat nature of CF infections. This study ...


Challenging The Paradigm Of Clinical Triazole Resistance In Aspergillus Fumigatus, Jeffrey Michael Rybak May 2019

Challenging The Paradigm Of Clinical Triazole Resistance In Aspergillus Fumigatus, Jeffrey Michael Rybak

Theses and Dissertations (ETD)

Invasive aspergillosis is a leading cause of morbidity and mortality among immunocompromised populations and is predicted to cause more than 200,000 life- threatening infections each year. Aspergillus fumigatus is the most prevalent pathogen isolated from patients with invasive aspergillosis, accounting for more than 60% of all cases. Currently, the only antifungal agents available with consistent activity against A. fumigatus are the mold-active triazoles and amphotericin B, of which the triazoles commonly represent both front-line and salvage therapeutic options. Unfortunately, the treatment of infections caused by A. fumigatus has recently been further complicated by the global emergence of triazole resistance ...