Microbiology Commons^™

The Identification And Characterization Of Novel And Improved Antigens For Next-Generation Pertussis Vaccines, Gage Michael Pyles

Graduate Theses, Dissertations, and Problem Reports (ETD)

Whooping cough, or pertussis, is a highly infectious respiratory disease caused by infection with the Gram-negative bacterial pathogen Bordetella pertussis. Pertussis affects all age groups and populations; however, it is most severe in infants who are too young to receive vaccinations and remains a global health concern with more than­­­­ 200,000 cases reported globally in 2023. Vaccines against pertussis have been available in the United States since the 1940’s with the development and widespread use of whole cell pertussis vaccines. Following their introduction, the incidence of pertussis was controlled and limited to fewer than 5,000 cases per year. Despite …

Investigating Birds As Dispersal Vectors Of Litylenchus Crenatae Subsp. Mccannii (Anguinidae), The Nematode Associated With Beech Leaf Disease, Spencer Rock Parkinson

Graduate Theses, Dissertations, and Problem Reports (ETD)

Beech leaf disease (BLD) is an emerging forest pathogen primarily affecting American beech (Fagus grandifolia, Ehrh.) in North America and has been attributed to tree mortality of sapling sized trees within five to seven years of infection. Symptoms typically occur in regenerating American beech thickets sprouting from roots of trees killed by beech bark disease. Scientists first observed BLD in Ohio in 2012 and currently has spread to 15 states in the USA and one Canadian province. The nematode Litylenchus crenatae subsp. mccannii (Lcm) is highly associated with BLD symptoms, interveinal chlorosis and defoliation of leaves, and is currently …

Co-Divergence Of Lemur Hosts And Gut Microbiomes Across Multiple Evolutionary Scales, Mariah E. Donohue

Theses and Dissertations--Biology

This dissertation bridges micro- and macroevolutionary approaches to understand the co-diversification of animal hosts and their gut microbiomes at different evolutionary timescales. I examined these dynamics using wild lemurs, a diverse Primate clade endemic to the island of Madagascar.

First, I tested the relative effects of host phylogenetic relationships, diet, and habitat in shaping the gut microbiome through deep evolutionary time and across distinct microbial kingdoms. I designed a natural experiment sampling feces from rainforest and dry forest lemur communities with similar phylogenetic assemblages and considerable variation in dietary strategy. Then, I amplified and sequenced two metabarcoding genes, the V4 …

Interactions Between Multiple Stressors, Nanomaterials And A Pathogen, In Caenorhabditis Elegans, Jarad Cochran

Theses and Dissertations--Plant and Soil Sciences

Metal and metal oxide nanoparticles (NP), which have received interest for use in agriculture, show in vitro and in vivo toxicity at relatively low concentrations. Silver nanoparticles (Ag NP) and zinc oxide nanoparticles (ZnO NP) cause adverse effects in model soil organisms under environmentally relevant conditions. In most toxicity assessments of nanomaterials, model organisms are exposed to a single stressor. Though single stressor experiments are essential to understanding the fate and effects of released NP, in nature, organisms are affected by multiple stressors, including pathogens, which might exacerbate or mitigate negative effects of NP exposure. There is limited research on …

The Role Of The Vibrio Cholerae Type Vi Secretion System During Kin Cell Interaction, Biofilm Formation And Priority Effects, Karen A. Castro

Dissertations and Theses

Vibrio cholerae’s Type VI secretion system (T6SS) is one of the arsenals used by the bacteria for its long-term survival in different environments, against a variety of opponents, and for its maintained pathogenicity in vulnerable regions of the world. Therefore, the more we understand about the activity of the T6SS, the closer we get to understanding its role in bacterial competition; inter-and-intra, and how this shapes a bacterial niche. Further, although the probiotic-like effect in the V. cholerae vaccine is described to work fast due to niche uptake hindering colonization of toxigenic strains, it is not yet clear if there …

The Effect Of Nanoconfined Liquid Properties On The Water-Responsive Behavior Of Bacterial Cell Walls, Seungri Kim

Dissertations and Theses

Water-responsive (WR) materials have the ability to mechanically swell and shrink in response to changes in relative humidity (RH). These WR materials are used by many biological systems to perform essential tasks; for example, pinecones use WR materials to release their seeds in dry environments, and wheat awns open and close to propel seeds into the soil, driven by daily RH changes. The WR actuation of some biomaterials is extremely powerful, for example Bacillus subtilis cell walls display record-high actuation energy and power densities of 72 MJ m^-3 and 9.1 MW m^-3, surpassing those of all existing …

The Development And Evaluation Of A Method For Complete Collagenase I Digestion Of Bos Taurus Bone Samples, Reilly Price

Master of Science in Forensic Science Directed Research Projects

Current methods for processing aged forensic bone samples for DNA analysis involve pulverization and organic extraction, which further destroys already degraded DNA and uses large amounts of limited samples. Additionally, the success rates for this type of analysis vary widely as homogenization incorporates PCR inhibitors into the sample. Little research has explored how pulverization results in DNA damage in profiles obtained from skeletal remains. This study proposes an enzymatic digestion method to separate osteocytes from PCR inhibitors in the extracellular bone matrix to improve the quality and quantity of DNA isolated from aged bone samples. The technique described here used …

The Sewage Microbiome Dynamics Of Different Serving Neighborhoods In Charleston, Illinois, Sandra Chiamaka Okoye

Masters Theses

The complex microbial ecosystem within sewage systems holds significant implications for environmental and public health. Unlike studies on wastewater treatment plant microbiomes, upstream sewage systems have not been studied widely. This research investigated the dynamic sewage microbiome across diverse serving neighborhoods in Charleston, Illinois, encompassing residential, hospital, industrial, and university areas. Drawing upon recent advancements in microbiome research, the study aimed to unravel the spatial and temporal variations in microbial structures. Three times between June to December 2023 sewage samples were collected from manholes in the areas mentioned above. Community DNA was extracted and sequenced for the V4-V5 region of …

Causal Association Between Gut Microbiomes And Different Types Of Aneurysms: A Mendelian Randomization Study, Youjia Qiu, Yucheng Hou, Xingzhou Wei, Menghan Wang, Ziqian Yin, Minjia Xie, Aojie Duan, Chao Ma, Ke Si, Zhong Wang

Faculty, Staff and Student Publications

BACKGROUND: Previous studies suggests that gut microbiomes are associated with the formation and progression of aneurysms. However, the causal association between them remains unclear.

METHODS: A two-sample Mendelian randomization was conducted to investigate whether gut microbiomes have a causal effect on the risk of intracerebral aneurysm (IA), thoracic aortic aneurysm (TAA) and abdominal aortic aneurysm (AAA), and aortic aneurysm (AA). Single nucleotide polymorphisms (SNPs) smaller than the locus-wide significance level (1 × 10

RESULTS: The phylum

CONCLUSION: Our MR analysis confirmed the causal association of specific gut microbiomes with AAA, and these microbiomes were considered as protective factors. Our result …

Investigating The Protein Interactome Of Escherichia Coli To Understand Metabolic Regulation When Proteins Bind: A Systems Biology Study., Shomeek Chowdhury

Theses and Dissertations

Proteins bind other proteins and work together as machines to perform many biological functions. Metabolic enzymes governing the life-sustaining metabolic reactions and therefore, metabolism are proteins which also binds other proteins. In this dissertation work, I have explored proteins when they interact with metabolic enzymes, play any role in regulating the cell’s metabolism. I study this phenomenon in Escherichia coli whose protein-protein interaction data is readily available in public databases with proper reference to the experimental study. Another good reason is the predictions we make in this computational study can be tested and validated in E. coli as it is …

Electrospun Tamarindus Indica-Loaded Antimicrobial Pmma/Cellulose Acetate/Peo Nanofibrous Scaffolds For Accelerated Wound Healing: In-Vitro And In-Vivo Assessments, Elbadawy A. Kamoun, Elbadawy A. Kamoun

Nanotechnology Research Centre

In this work, Tamarindus indica (T. indica)-loaded crosslinked poly(methyl methacrylate) (PMMA)/cellulose acetate (CA)/poly(ethylene oxide) (PEO) electrospun nanofibers were designed and fabricated for wound healing applications. T. indica is a plant extract that possesses antidiabetic, antimicrobial, antioxidant, antimalarial and wound healing properties. T. indica leaves extract of different concentrations were blended with a tuned composition of a matrix comprised of PMMA (10 %), CA (2 %) and PEO (1.5 %), and were electrospun to form smooth, dense and continuous nanofibers as illustrated by SEM investigation. In vitro evaluation of T. indicaloaded nanofibers on normal human skin fibroblasts (HBF4) revealed a high …

The Role Of Osaa Gene In Aspergillus Fumigatus Development, Secondary Metabolism And Virulence., Apoorva Dabholkar

Graduate Research Theses & Dissertations

Aspergillus fumigatus is the leading cause of aspergillosis, associated with high mortality rates, particularly in immunocompromised individuals. In search of novel genetic targets against aspergillosis, we studied the WOPR transcription factor OsaA. Deletion of the osaA gene resulted in colony growth reduction. Conidiation is also influenced by osaA; both osaA deletion and overexpression resulted in a decrease in spore production. Wild-type expression levels of osaA are necessary for expression of the conidiation regulatory genes brlA, abaA and wetA. In addition, osaA is necessary for normal cell wall integrity. Furthermore, deletion of osaA resulted in a reduction in the ability of …

Ascertaining A Biochemical Approach To Chlorophyll D Biosynthesis In Acaryochloris Spp., Rashmi Shivni

Graduate Research Theses & Dissertations

Photosynthesis is one of the most abundant metabolic systems on Earth, and specifically, oxygenic photosynthesis primed the planet for complex, multicellular life. The hallmark of modern oxygenic photosynthesis is the photopigment chlorophyll a found in nearly all oxygenic phototrophs as their primary photopigment in their photosynthesis pathways. There are also many organisms that tap into a variety of chlorophylls to extend the energetic limits of photosynthesis, which are largely found as accessory pigments. One genus of cyanobacteria, Acaryochloris, has garnered attention for the ability to undergo photosynthesis by harnessing the far-red part of the visible light spectrum using chlorophyll d …

Molecular Investigation Of Tick-Borne Pathogens In Feral Swine (Sus Scrofa) From Seven Us States, Sofiane Aiche

Masters Theses

Feral swine (Sus scrofa) have been proposed as part of the lifecycles of multiple tickborne pathogens (TBP). This is a result of the increase in feral swine populations and increased tick populations and geographic ranges. Few surveys exist on the TBP relevant to human and wildlife of feral swine in the US. The aim of this study is to investigate the prevalence of 10 TBP: Anaplasma spp., Borrelia spp., Cytauxzoon felis, Hepatozoon spp., Babesia spp., Mycoplasma spp., Trypanosoma cruzi, Toxoplasma gondii, Yersinia pestis, and Rickettsia spp. A total of 87 feral swine blood samples …

Leveraging Bioinformatics To Understand Chlorophyll D Biosynthesis In Acaryochloris Spp., Dikshyant Gautam

Graduate Research Theses & Dissertations

Acaryochloris strains can adapt into far red region of the visible spectrum by utilizing its unique chlorophyll called chlorophyll d (Chl d). The genetic machinery behind Chl d has not been discovered yet. Biosynthetic pathway for other chlorophylls like chlorophyll a, chlorophyll b and chlorophyll f found in cyanobacteria are however well known. This research aims to understand the biosynthetic pathway responsible for chlorophyll d production. Bioinformatics approaches like comparative genomics, machine learning, and weighted gene co-expression network analysis (WGCNA) were central in this study to identify candidate genes and regulatory mechanisms potentially involved in chlorophyll d synthesis.

An important …

Dust-Driven Mechanism For Marine Particle Aggregation: Interactions Between Clay Minerals, Heterotrophic Bacteria And Organic Matter Influences Aggregation In Marine Systems, Vignesh Gokuladas Menon

Dartmouth College Master’s Theses

Atmospheric dust deposition plays a crucial role in marine biogeochemical cycles, yet mechanisms underlying its impact on particle dynamics remain unclear. This study investigates the synergistic interactions between marine heterotrophic bacteria and clay minerals in seawater, focusing on their effect on Transparent Exopolymer Particles (TEP) production and organoclay aggregation. Field experiments in the Gulf of Maine and laboratory roller tank studies were conducted using natural microbial communities and model heterotrophic bacterial strains (Alteromonas sp. EZ55, Marinobacter adhaerens HP15, and Sulfitobacter sp. NAS-14.1). Results demonstrate that clay exposure significantly enhances TEP production by bloom-associated heterotrophic bacteria, with increases up to …

Optimization Of An Immune Assay To Detect Binding Of Nod2 To Staphylococcus Aureus, Precious Mckenzie

All Student Theses and Dissertations

Staphylococcus aureus, a gram-positive, commensal bacterium, is the cause of a multitude of opportunistic diseases and infections. While S. aureus has evolved ways to escape innate immune responses in the host, the mechanisms are not fully understood. One area of active research involves mechanisms by which S. aureus avoids detection by Pattern Recognition Receptors (PRRs), such as Nuclear Oligomerization Domain 2 (NOD2), present on the surface of and inside innate immune cells. This study aimed to design and optimize an assay that can be utilized to investigate S. aureus components that contribute to the activation of NOD2 receptors. The …

In Vitro Assessment Of The Anti-Biofilm Effectiveness Of Copper And Zinc Enhanced Borate Bioactive Glass Using Processed Microscopic Images, Sarah Fakher, David J. Westenberg

Biological Sciences Faculty Research & Creative Works

The escalating burden of nosocomial infections presents a formidable challenge to healthcare systems worldwide, leading to increased morbidity, prolonged hospital stays, and elevated healthcare costs. These infections are often resistant to conventional antibiotic therapies due to their association with biofilms which contribute to the persistence and resistance of pathogens. In addressing the challenge of biofilm-associated nosocomial infections, borate bioactive glasses (BBGs) have emerged as promising biomaterials. Doping these glasses with antimicrobial metals could potentially harness their antibacterial properties to prevent biofilm formation. This study undertakes a rigorous evaluation of the anti-biofilm efficacy of copper and zinc-doped BBGs by employing processed …

A Molecular-Informed Species Inventory Of The Order Ceramiales (Rhodophyta) In The Narragansett Bay Area (Rhode Island And Massachusetts), Usa, Thomas Irvine, Brian Wysor, Alicia Beauvais

Arts & Sciences Faculty Publications

Narragansett Bay is an estuarine system in the western North Atlantic Ocean that harbors a diverse marine flora, providing structure, habitat, and food for native biodiversity. This area has been the center of numerous environmental, biological, ecological, and oceanographic studies; however, marine macroalgae have not been extensively examined using modern molecular methods. Here, we document the biodiversity of the red algal order Ceramiales based on DNA sequence comparisons of the 3′ end of the RuBisCo large subunit (rbcL-3P) and the universal plastid amplicon (UPA). Thirty-seven distinct species of this order were identified and validated with molecular data, including five new …

Application Of Environmental Dna Metabarcoding To Differentiate Algal Communities By Littoral Zonation And Detect Unreported Algal Species, Sergei Bombin, Andrei Bombin, Brian Wysor, Juan M. Lopez-Bautista

Arts & Sciences Faculty Publications

Coastal areas are the most biologically productive and undoubtedly among the most complex ecosystems. Algae are responsible for most of the gross primary production in these coastal regions. However, despite the critical importance of algae for the global ecosystem, the biodiversity of many algal groups is understudied, partially due to the high complexity of morphologically identifying algal species. The current study aimed to take advantage of the recently developed technology for biotic community assessment through the high-throughput sequencing (HTS) of environmental DNA (eDNA), known as the “eDNA metabarcoding”, to characterize littoral algal communities in the Northern Gulf of Mexico (NGoM). …

Ribosome Hibernation Factor Induces Antibiotic Persisters Of Mycobacterium Tuberculosis In Neutrophil-Rich Lung Lesions, Jamie Corro

Electronic Theses & Dissertations (2024 - present)

Mycobacterium tuberculosis (Mtb), the etiological agent of tuberculosis, is a prescient global health threat and the leading cause of death by an infectious agent. Treatment of Mtb infection involves administering 2-4 antibiotics for a minimum of 6 months. This extended drug regimen is required to target a subpopulation of persistent bacilli. As their name implies, these bacteria can “persist” by acquiring nonhereditary and transient antibiotic tolerance. Although the precise mechanism is unknown, it’s often attributed to slowing cellular growth and metabolic processes. During zinc deprivation, bacteria can remodel their ribosomes by replacing their zinc-binding paralogues containing the CXXC motif (C+) …

Factors Associated With Hepatitis C-Related Hospitalizations And Inpatient Mortality In The United States, Pre- And Post-Onset Of The Covid-19 Pandemic, Christina R. Samuel

College of Graduate Studies: Theses & Dissertations

Background: Hepatitis C is a significant public health problem in the United States and imposes a substantial burden on the healthcare system. Previous research shows that the COVID-19 pandemic response efforts have overshadowed hepatitis C testing and treatment measures in health care settings across the country. The purpose of this study was to describe and examine the factors associated with hepatitis C-related hospitalizations and inpatient mortality in the United States, pre- and post-onset of the COVID-19 pandemic. Methods: Data were obtained from the 2019-2020 National Inpatient Sample database. The study population included persons aged ≥18 years with hepatitis C-related inpatient …

Social Interactions And Spatial Structure Drive Community Assembly Of Bacterial Biofilm, Matthew C. Bond

Dartmouth College Ph.D Dissertations

Despite the critical nature which microbial communities play in the natural world and human civilization, the breadth of understanding remains shallow. Challenged by scale, high variability between environments, and extensive diversity, microbial ecologists strive to understand connections between a community’s structure and function, as well as the ecological and evolutionary mechanisms underlying observed natural patterning of communities. Biofilms are the predominate mode of growth for microbial communities—characterized by cellular attachment to a surface via a self-produced matrix and heterogeneous structure, often resulting in a primary growth front along the biofilm surface due to differential access to bulk nutrients (cite). This …

Synthetic Microbial Communities For Plastic Upcycling, Isabel B. A. Valencia

Dissertations, Master's Theses and Master's Reports

Plastic waste and human hunger pose major threats to the health and wellbeing of populations world-wide. Using microbial methods to upcycle polyethylene terephthalate (PET) plastic into value-added compounds such as single cell protein (SCP) for human consumption is a unique solution to both these issues. Two monomers of chemically deconstructed PET (DCPET), terephthalate (TPA) and ethylene glycol (EG), have been previously shown to be biodegradable by enriched microbial communities. Using this top-down knowledge to inform the reconstruction of a minimal microbial community constructed from isolated members of these communities is a novel way to efficiently process these monomers via a …

Determination Of Spore Viability In Concrete Across Several Factors Using Most Probable Number, Samuel Boyer

Williams Honors College, Honors Research Projects

To determine the lowest concentration of spore added to polyurethane-cement composite (PUCCO) particles that can still germinate after curing in concrete. This research project is a small addition to the larger research project being undertaken by Mirza Mohammed Rashiduzzaman for his Masters. The larger project involves the use of fungal spores added in concrete to act as a self-healing component when cracks form in the concrete structure over time. These spores are suspended in a protective oil and loaded into small, hardened sponge-like PUCCO cubes to act as growth points when water and air can reach the PUCCO in the …

Optimization Of Buffers Used In Phycobiliprotein Extraction From The Cyanobacterium Acaryochloris Marina, Rinah Fleisher

Williams Honors College, Honors Research Projects

Optimization of buffers used in phycocyanin extraction from A. marina was explored including acetate, phosphate, and citrate buffers as well as deionized water as a negative control. Samples were extracted in triplicates for each trial with two extraction trials completed overall for citrate buffer (n=6), phosphate buffer (n=6), acetate buffer (n=6), and deionized water (n=6). Results reflect no statistical difference in phycocyanin content (μg/mL) between each buffer or deionized water control. Though no statistically significant differences between treatment groups were found, phosphate buffer yielded the greatest phycocyanin content and the deionized water negative control yielded the lowest phycocyanin content overall. …

Scale And Habitat Effects On Measurement Of Streptomyces Biogeography And Biodiversity, Terilyn A. Stoflet

Cal Poly Humboldt theses and projects

Bacteria in the genus Streptomyces are detected in most soils around the world, as well as on and in seeds, plants, animals, insects and the wind. Currently, more than 700 valid species of Streptomyces have been identified worldwide. Streptomyces produce the majority of antibiotics, antivirals and antifungals, as well as important agricultural bioactive molecules due to their unique genetic capabilities. Their distinct genetic abilities allow them to produce an unlimited amount of biosynthetic gene clusters, or BGC’s. Although many compounds come from Streptomyces, scientists have not discovered the biogeographic patterns of this genus. The biogeography of Streptomyces is a …

Listeria Adhesion Protein Orchestrates Caveolae-Mediated Apical Junctional Remodeling Of Epithelial Barrier For Listeria Monocytogenes Translocation, Rishi Drolia, Donald B. Bryant, Shivendra Tenguria, Zuri A. Jules-Culver, Jessie Thind, Breanna Amelunke, Donqi Liu, Nicholas L. F. Gallina, Krishna K. Mishra, Manalee Samaddar, Manoj R. Sawale, Dharmendra K. Mishra, Abigail D. Cox, Arun K. Bhunia

Biological Sciences Faculty Publications

The cellular junctional architecture remodeling by Listeria adhesion protein-heat shock protein 60 (LAP-Hsp60) interaction for Listeria monocytogenes (Lm) passage through the epithelial barrier is incompletely understood. Here, using the gerbil model, permissive to internalin (Inl) A/B-mediated pathways like in humans, we demonstrate that Lm crosses the intestinal villi at 48 h post-infection. In contrast, the single isogenic (lap− or ΔinlA) or double (lap−ΔinlA) mutant strains show significant defects. LAP promotes Lm translocation via endocytosis of cell-cell junctional complex in enterocytes that do not display luminal E-cadherin. In comparison, InlA facilitates …

Salmonella Detection In Food Using A Hek-Htlr5 Reported Cell-Based Sensor, Esma Eser, Victoria A. Felton, Rishi Drolia, Arun K. Bhunia

Biological Sciences Faculty Publications

The development of a rapid, sensitive, specific method for detecting foodborne pathogens is paramount for supplying safe food to enhance public health safety. Despite the significant improvement in pathogen detection methods, key issues are still associated with rapid methods, such as distinguishing living cells from dead, the pathogenic potential or health risk of the analyte at the time of consumption, the detection limit, and the sample-to-result. Mammalian cell-based assays analyze pathogens’ interaction with host cells and are responsive only to live pathogens or active toxins. In this study, a human embryonic kidney (HEK293) cell line expressing Toll-Like Receptor 5 (TLR-5) …

Ecophysiology Of Bradyrhizobium Diazoefficiens Usda 110, Armaan Kaur Sandhu

Electronic Theses and Dissertations

With increasing demand for soybean, maximizing plant yield is important yiel is dependent on nitrogen availability, but nitrogen fertilizers can meet the plant's needs but have severe environmental impacts. An economically and environmentally sustainable approach is to enhance nitrogen availability through Biological Nitrogen Fixation by symbiotic rhizobia, Bradyrhizobium, an efficient nitrogen fixer for soybean. This symbiosis begins with attachment of rhizobia to legume roots. Root and rhizobia surface properties play a significant role in this attachment. Another major factor affecting root colonization is bacterial competition ability. There is a lack of knowledge on the role of bacterial surface properties, competition …