The Impact Of Nutrient Depletion On The Effect Of Hhq On Emiliania Huxleyi,
2023
University of New Hampshire, Durham
The Impact Of Nutrient Depletion On The Effect Of Hhq On Emiliania Huxleyi, Marley Gonsalves
Honors Theses and Capstones
Emiliania huxleyi is a ecologically important, bloom-forming coccolithophore. HHQ is a bacteria compound that causes cell stasis in E. huxleyi that can lead to bloom termination. This study analyzed the role that nutrient depletion plays in this relationship. Results show that nitrogen depletion protects cells from the effects of HHQ, affecting bloom dynamics.
Identification Of Novel Biosynthetic Gene Clusters Encoding For Polyketide/Nrps-Producing Chemotherapeutic Compounds From Marine-Derived Streptomyces Hygroscopicus From A Marine Sanctuary,
2023
University of New Hampshire, Durham
Identification Of Novel Biosynthetic Gene Clusters Encoding For Polyketide/Nrps-Producing Chemotherapeutic Compounds From Marine-Derived Streptomyces Hygroscopicus From A Marine Sanctuary, Hannah Ruth Flaherty
Honors Theses and Capstones
Nearly one out of six deaths in 2020, around ten million people, were caused by cancer, making it a leading cause of death worldwide (WHO, 2022). This major public health issue, in addition to the rise of multidrug-resistant (MDR) pathogens, provides a high demand for the discovery of new pharmaceutical drugs to be used clinically to treat these conditions. The Streptomyces genus accounts to produce 39% of all microbial metabolites currently approved for human health, indicating its potential as an important species to study for antimicrobial and anticancer agents. The long linear genome of Streptomyces contains specialized sequences known as …
Effect Of Soil Ph And Indigenous Bacterial Populations In Selecting Rhizobial Endophytes Within Soybean Root Nodules,
2023
Missouri State University
Effect Of Soil Ph And Indigenous Bacterial Populations In Selecting Rhizobial Endophytes Within Soybean Root Nodules, Brianne Danielle Edwards
Graduate Theses/Dissertations
Soybean plants fulfill most of their nitrogen requirement by developing symbiotic associations with four different rhizobial genera, including Bradyrhizobium, Sinorhizobium, Mesorhizobium, and genus Rhizobium. In general, members of Bradyrhizobium and Sinorhizobium have been reported as dominant root nodule endophytes under acidic soils and alkaline soil conditions, respectively. So far, it is unknown whether the selection of rhizobial endophytes is regulated by their ability to survive under different soil pH or driven by host plants regardless of their relative abundance in soil. This study was focused on the assessment of the potential role of soil pH in …
Understanding Human Gut Bacterial Interactions And Their Role In Colonization Resistance Against Clostridioides Difficile Using Mini-Bioreactor Array And Caenorhabditis Elegans As Model Systems,
2023
South Dakota State University
Understanding Human Gut Bacterial Interactions And Their Role In Colonization Resistance Against Clostridioides Difficile Using Mini-Bioreactor Array And Caenorhabditis Elegans As Model Systems, Achuthan Ambat
Electronic Theses and Dissertations
No abstract provided.
Investigating The Effectiveness Of Microplastic Removal And The Relationship Between Microplastics, Bacterial Communities, And Nitrogen Cycling In The Natural Treatment Systems At The Arcata Wastewater Treatment Facility,
2023
Humboldt State University
Investigating The Effectiveness Of Microplastic Removal And The Relationship Between Microplastics, Bacterial Communities, And Nitrogen Cycling In The Natural Treatment Systems At The Arcata Wastewater Treatment Facility, Fiona Connor
Cal Poly Humboldt theses and projects
This thesis addressed two challenging aspects of microplastic research, including the quantification of microplastics in organic-rich water, and the investigation of how microplastics impact microorganisms and related nutrient-cycling. Two projects were designed and executed to address specific research objectives relating to these broad topics. The first objective was to develop and implement methods to determine the effectiveness of microplastic removal across the natural treatment systems at the Arcata Wastewater Treatment Facility (AWTF). The second objective was to observe how microplastics found in domestic wastewater impact the bacterial communities and nitrogen cycling in freshwater treatment wetland sediment through a bench-scale experiment, …
Host-Microbe Interactions In Non-Native Estuarine Anemones: Biogeography And Temperature,
2023
Cal Poly Humboldt
Host-Microbe Interactions In Non-Native Estuarine Anemones: Biogeography And Temperature, Parker K. Lund
Cal Poly Humboldt theses and projects
Non-native species are increasing in prevalence around the world, resulting in negative economic and ecological impacts. However, the broad distributions of non-native species also offer a system for investigating the response of host-associated microbial communities to environmental factors across a range of ecological scales. At the broadest scale, I investigated the geography of microbial communities in the non-native estuarine anemone Diadumene lineata on the west coast of the United States of America. Across latitudes, microbial community composition was very similar and displayed a high percentage of Klebsiella spp. at all sites. However, the communities in California tended to exhibit higher …
Community Ecology And Disease Dynamics In Pacific Oysters: Unraveling Microbiome-Pathogen Interactions In The Wild,
2023
Cal Poly Humboldt
Community Ecology And Disease Dynamics In Pacific Oysters: Unraveling Microbiome-Pathogen Interactions In The Wild, Victoria E. Cifelli
Cal Poly Humboldt theses and projects
In the context of multispecies microbial assemblages, disruptions can occur when there are alterations in host conditions, such as the onset of a disease. Notably, viruses have the potential to reshape a host's microbial community. However, the role of the host's habitat and environment, which could be pivotal in communities with shifting niche space and habitat filters, is often overlooked in host-microbe-pathogen interactions. Recognizing the importance of these factors, I employed a field-based approach to understand microbial community dynamics in the presence of disease. To address the influence of geographical location, I conducted an analysis involving healthy and infected oysters …
Extension Of The Ergot Alkaloid Gene Cluster,
2023
West Virginia University
Extension Of The Ergot Alkaloid Gene Cluster, Samantha Joy Fabian
Graduate Theses, Dissertations, and Problem Reports (ETD)
Specialized metabolites produced by fungi impact human health. A large portion of the pharmaceuticals currently on the market are derived from metabolites biosynthesized by microbes. Ergot alkaloids are a class of fungal metabolites that are important in the interactions of environmental fungi with insects and mammals and also are used in the production of pharmaceuticals. In animals, ergot alkaloids can act as partial agonists or antagonists at receptors for 5-hydroxytryptamine (serotonin), dopamine, and noradrenaline as ergot alkaloids have chemical structures similar to those neurotransmitters. Therefore, they affect insects and mammals that consume them and can be used to produce drugs …
Effect Of Soil Transplantation On Fungal Communities During Restoration,
2023
Central Washington University
Effect Of Soil Transplantation On Fungal Communities During Restoration, Thomas Luehl
All Master's Theses
Ectomycorrhizal fungi are integral parts of natural ecological systems that provide access to nutrients that would otherwise be unavailable by forming symbiotic relationships with plants. Relationships with ectomycorrhizal fungi are known to improve plant growth rate, increase plant resistance to pathogens, and improve survival. Current revegetation practices often ignore this relationship between fungi and plants. During the revegetation of the Interstate 90 Keechelus Lake wildlife overcrossing (Easton, WA), soil from forest sites adjacent to the restoration area were collected and used to inoculate a set of experimental plots to determine whether ectomycorrhizal fungi would become established in the plots and …
Under Ice Photosynthetic Primary Production And Dark Carbon Fixation In A Temperate Freshwater System,
2023
Michigan Technological University
Under Ice Photosynthetic Primary Production And Dark Carbon Fixation In A Temperate Freshwater System, Vanessa Cubillos Tellez
Dissertations, Master's Theses and Master's Reports
Ice-covered lakes are vulnerable to environmental change, especially those in the Northern Hemisphere where ice cover is rapidly declining due to global warming. These changes can alter metabolic processes and disrupt carbon cycling driven by primary producers who form the base of the food chain and are key to sustaining ecosystem function. Photosynthetic primary production and dark carbon fixation under the ice in the Keweenaw Waterway, a temperate freshwater system that is ice-covered for ~3 months out of the year, were studied using a carbon isotopic labeling (14C-bicarbonate) technique. Water samples were collected weekly during ice cover and monthly during …
Evaluation Of Welded And Polished Stainless-Steel Surfaces In Supporting Sporeformer Biofilms In Dairy Plants,
2023
South Dakota State University
Evaluation Of Welded And Polished Stainless-Steel Surfaces In Supporting Sporeformer Biofilms In Dairy Plants, Taghreed Almalki
Electronic Theses and Dissertations
No abstract provided.
Fine-Scale Genetic Structure In Rhizosphere Microbial Communities Associated With Chamaecrista Fasciculata (Fabaceae),
2023
Mississippi State University
Fine-Scale Genetic Structure In Rhizosphere Microbial Communities Associated With Chamaecrista Fasciculata (Fabaceae), Mahboubeh Hosseinalizadeh Nobarinezhad, Lisa E. Wallace
Biological Sciences Faculty Publications
Soil microbiota of the rhizosphere are an important extension of the plant phenotype because they impact the health and fitness of host plants. The composition of these communities is expected to differ among host plants due to influence by host genotype. Given that many plant populations exhibit fine-scale genetic structure (SGS), associated microbial communities may also exhibit SGS. In this study, we tested this hypothesis using Chamaecrista fasciculata, a legume species that has previously been determined to have significant SGS. We collected genetic data from prokaryotic and fungal rhizosphere communities in association with 70 plants in an area of …
Optimizing Sample Collection And Data Interpretation For Effective Wastewater-Based Epidemiology In Combined Sewer Systems,
2023
West Virginia University
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; …
Evaluating Innovative Methods Of Quantitatively Linking Microbial Community Structure To Ecosystem Function,
2023
West Virginia University
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 …
Triclosan Degrading Bacteria From Wastewater Treatment Plants In Central Illinois,
2023
Eastern Illinois University
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 …
Attachment Issues: Microbes, Minerals, And The Persistence Of Soil Organic Matter,
2023
West Virginia University
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, …
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,
2023
University of North Florida
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 …
Exploring The Microbial Composition Of Moonmilk In Wind Cave National Park,
2023
University of Northern Iowa
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 …
Evaluation Of Methods To Analyze Microbial Composition In Soils,
2023
University of Northern Iowa
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 …
Characterizing The Rhizosphere Microbial Community Of Food Crops In A Changing Climate,
2023
Wilfrid Laurier University
Characterizing The Rhizosphere Microbial Community Of Food Crops In A Changing Climate, Samuel Snider
Theses and Dissertations (Comprehensive)
In recent years, there have been increased occurrences of food-borne illness in Canada, which is not directly associated with animal-related products but is caused by the increasing prevalence of pathogenic outbreaks in fresh produce. This can have health and economic impacts on the agriculture industry in Canada. As such, it is essential to better understand the plant-microbe interactions of crops grown in Canada and determine how climate change may alter the relationship. Plants can promote the growth of beneficial bacteria in the rhizosphere, which can create protective competition between beneficial and pathogenic bacteria. Changes in the environment of the rhizosphere …
