Environmental Microbiology and Microbial Ecology Commons^™

Connecting The Nebraska Water Quality Index To The Aquatic Microbial Community Of The North Platte River Basin, Nebraska, Paula R. Guastello

School of Natural Resources: Dissertations, Theses, and Student Research

The Nebraska Water Quality Index, under development by the Nebraska Department of Environment and Energy, summarizes in a single value eight environmental parameters that have been monitored in Nebraska for nearly 20 years. Water quality parameters including those used in the Nebraska Water Quality Index have been shown in previous studies to impact bacterial growth. As such, this index has the potential to correlate with the freshwater microbial community. Here, I relate the Nebraska Water Quality Index to microbial community composition and structure using 16S rRNA gene amplicon sequence data collected from the North Platte River Basin, Nebraska. This index …

A Review On Validation Of Enzyme Linked Immunosorbent Assay (Elisa) Techniques For Detection And Quantification Of Different Contaminant In Aquatic Environment, Sanwal Aslam, Zhen Zhang, Ali Muhammad

Journal of Bioresource Management

In world, contaminants and microbes are considered as serious problem in house water supplies as well as in aquatic environment for life. As a result, different countries are working to set level of these contaminants and microbes in domestic supply of water and in aquatic environment. In addition to these scientists are also working on reliable sampling and then their suitable analysis method for accuracy. It is also very important to improve and give justification for analytical techniques used in laboratories, which enable us to monitor level of various contaminants in aquatic environment. In this review, we have focused on …

Long-Term Impacts Of Conservation Pasture Management In Manuresheds On System-Level Microbiome And Antibiotic Resistance Genes, Mitiku Mihiret Seyoum, Amanda Ashworth, Kristina M. Feye, Steven C. Ricke, Phillip R. Owens, Philip A. Moore Jr., Mary Savin

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Animal manure improves soil fertility and organic carbon, but long-term deposition may contribute to antibiotic resistance genes (ARGs) entering the soil-water environment. Additionally, long-term impacts of applying animal manure to soil on the soil-water microbiome, a crucial factor in soil health and fertility, are not well understood. The aim of this study is to assess: (1) impacts of long-term conservation practices on the distribution of ARGs and microbial dynamics in soil, and runoff; and (2) associations between bacterial taxa, heavy metals, soil health indicators, and ARGs in manures, soils, and surface runoff in a study following 15 years of continuous …

Evaluation Of Organic And Synthetic Herbicides Applications On Indicators Of Soil Health And Weed Suppression In A Conventional Cropping System In Louisiana, Caitlin Denux

LSU Doctoral Dissertations

Synthetic herbicides, with their varying modes of action, are well known for their efficiency in the suppression and control of weed species in U.S. agriculture. However, the consequences of using synthetic herbicides without attention to the surrounding environment can produce chemical run-off, changes in soil health and soil health conditions, and create herbicide-resistant weeds. These consequences have encouraged growers to find alternatives in their weed management programs. In this study, organic and synthetic herbicides were assessed on how well they performed in weed suppression surveys, and their potential effects on soil health indicators. Commonly used indicators include soil pH, β-glucosidase …

Investigating Potential Indicators Of Soil Health Through Microbiome Response To Environmental And Anthropogenic Stressors, Austin Cook

Theses and Dissertations

Traditionally, the analysis of soil health has overlooked the biological component of soil due to poor understanding of connections between the microbiome and empirically measured soil health indicators. The purpose of this study was to assess the effects of environmental and anthropogenic stressors on the soil microbiome, with the aim of identifying measurable soil biological indicators. Chosen soils were examined under distinct conditions to evaluate the effect of selected environmental and anthropogenic stressors on the microbiome. Soil biological responses were analyzed via enzymatic response, microbial functional genes, and microbial community. Environmental factors such as soil moisture and organic matter showed …

Sensing The Rhizosphere: Microbial Transcriptome Responses To Root Exudates And Redox-Active Metabolites, Ankita Bhattacharyya

Dissertations

The term “rhizosphere” describes the dynamic interface between plant roots and soil influenced by root exudates. It is a hotspot of microbial activity, plant-microbe, and microbe-microbe interactions. Distinct variations in bacterial diversity are thought to be driven by plant root exudates. However, the molecular details of these processes still remain unclear.

I addressed this gap by focusing on two strains, Pseudomonas synxantha 2-79 and Burkholderia lata 383, representing diverse groups of Gammaproteobacteria comprised of species with environmental, agricultural, and medical significance. In the first part of this project, we used a combination of metabolomics and RNA-seq to characterize transcriptome responses …

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

All Dissertations

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

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

Microbial Commensals Of Tricolored Bats In Georgia And Their Probiotic Potential, Jordyn Upton

Master of Science in Integrative Biology Theses

Pseudogymnoascus destructans (Pd) is a fungal pathogen that has been spreading in North American bats since its initial discovery in 2006. P. destructans is the causative agent of white-nose syndrome (WNS), a disease leading to as much as a 90% decrease in some eastern United States bat populations, with select hibernacula experiencing complete extirpation of the hibernating population. To date, there is no effective scaled probiotic for WNS, but probiotics inoculums have shown success in the management of other recently emerged fungal pathogens of wildlife, such as chytridiomycosis in amphibians. Host microbiomes have come under investigation in other disease systems …

Diving Into Aquatic Microbial Ecology And Evolution With Anne Thompson, Anne Thompson

PDXPLORES Podcast

On this episode of PDXPLORES, Assistant Professor of Biology, Anne Thompson, discusses her award-winning research work studying the diverse ecology of microorganisms found in Earth’s oceans. Thompson’s research examines microbial mortality impacts on the structure of oceanic food webs, carbon flow, and cell interactions that create dynamic patterns of nutrient and energy abundance within diverse aquatic ecosystems.

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Sympatric Soil Microbe Interactions Between Streptomyces And Fusarium Isolates, Lehren A. Olk-Szost

All NMU Master's Theses

Interkingdom interactions between soil bacteria and fungi may play a critical role in occurrence of disease suppressive soils, yet our understanding of these interactions remains limited. Streptomyces are well-known producers of antimicrobial compounds important to medicine and agriculture. Production of these secondary metabolites is often mediated by quorum sensing. Most Streptomyces research occurs in single species experiments, yet new metabolites have been discovered in interspecies co-culture experiments. Interspecies, intergenic, and interkingdom co-culture research will likely reveal many valuable compounds, and strengthen our understanding of complex ecological interactions in soil microbiomes. Interactions between sympatric Streptomyces and Fusarium isolates from disease suppressive …

Endophytic Potential Of Entomopathogenic Fungi For The Remediation Of Wastewater, Huda Bilal, Hasnain Raza, Sana Sarfaraz, Danyal Haider Khan

Journal of Bioresource Management

Phytoremediation has the potential to significantly reduce water contamination caused by excessive harmful chemicals. The degradative properties of fungi are used in fungal phytoremediation to eliminate or neutralise the hazardous pollutants present in water. The goal of the current study was to endophytize water lettuce with the two entomopathogenic fungus Metarhizium anisopilae and Trichoderma harazium. The plant is inoculated with the fungus using the root-dipping procedure. There were two main treatments and a control all with five replications. The analysis of plant and wastewater were analyzed initially like frequency of fungus remained in plant weight, root length and for …

Symbiotic Ucyn-A Strains Co-Occurred With El Niño, Relaxed Upwelling, And Varied Eukaryotes Over 10 Years Off Southern California, Colette Fletcher-Hoppe, Yi-Chun Yeh, Yubin Raut, J. L. Weissman, Jed A. Fuhrman

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Biological nitrogen fixation, the conversion of N₂ gas into a bioavailable form, is vital to sustaining marine primary production. Studies have shifted beyond traditionally studied tropical diazotrophs. Candidatus Atelocyanobacterium thalassa (or UCYN-A) has emerged as a focal point due to its streamlined metabolism, intimate partnership with a haptophyte host, and broad distribution. Here, we explore the environmental parameters that govern UCYN-A’s presence at the San Pedro Ocean Time-series (SPOT), its host specificity, and statistically significant interactions with non-host eukaryotes from 2008-2018. 16S and 18S rRNA gene sequences were amplified by “universal primers” from monthly samples and resolved into Amplicon …

Reproduction, Early Development, And Larval Rearing Of The Climbing Perch Anabas Testudineus (Teleostei: Anabantidae) In Captivity, Frolan A. Aya, Reylan C. Gutierrez, Luis Maria B. Garcia

The Philippine Agricultural Scientist

Induced spawning, early development, and larval rearing of the climbing perch Anabas testudineus were examined under captive conditions. Five female climbing perch [125.33 ± 3.27 mm SL; 70.67 ± 5.59 g BW] were paired with apparently mature males (108.50 ± 3.97 mm SL; 39.27 ± 4.70 g BW) and induced to spawn with 5,000 IU human chorionic gonadotropin (hCG) + 0.5 mL Ovaprim kg BW^-1. All hCG + Ovaprim-injected fish spawned 9 – 11 h after hormone administration but saline-injected fish (control group) failed to spawn. Mean egg production per female, fertilization and hatching rates, and larval production …

Ecology Of Viruses In Marine And Coastal Oxygen-Depleted Waters, Sophie Jurgensen

LSU Doctoral Dissertations

Deoxygenation of marine and coastal waters, both caused and exacerbated by a suite of abiotic and biotic factors, has been documented for more than sixty years. The incidence and severity of low-oxygen areas is predicted to expand globally in the coming decades. Despite their colloquial moniker “dead zones,” low-oxygen areas contain thriving and diverse microorganisms that have significant impacts on global biogeochemical cycles including contributing to positive feedback loops that further expand low-oxygen areas. While the diversity and activity of these microorganisms is beginning to be elucidated, the ecology of their viruses is particularly understudied. In this dissertation, I present …

Effects Of Climate Change On Human Health, Sara El Houzaly, Richa Gupta

Publications and Research

The effects of climate change are evident worldwide as average global land and air temperatures have been rising, glaciers and ice sheets are shrinking with the concomitant rise in sea levels, extreme weather events have become more frequent, and oceans are warming and acidifying. Humanity is facing a big environmental challenge which not only impacts our habitat but will also have ramifications on our health. The present review describes a detailed examination of the scientific evidence proving the relationship between climate change and various fatal human diseases in different geographical regions. Our findings indicate that variations in the patterns of …

The Influence Of Sampling Frequency On Bee Species Richness, Courtney Caccamo

Biology Student Scholarship

As one of Earth’s most valuable pollinators, bees provide important pollination services to wild plant species and crops alike (Winfree 2010). But, in recent years, bee populations appear to be declining due to a variety of anthropogenic drivers (Potts et al. 2010). Quantifying the extent of bee population decline is difficult because there is currently a lack of a standardized protocol for how best to survey bee populations (Tepedino & Portman 2021). One of the commonly used survey methods is pan trapping, which involves leaving out yellow, white, and blue bowls filled with soapy water to passively sample the species …

Considerations For The Use Of Mycorrhizal Fungi Inoculants In Coal Mine Reclamation And Reforestation In Appalachia: A Guide Of Best Practices And Management Recommendations, Cole Hansen Reistrup

Master's Projects and Capstones

Nearly all terrestrial plants form symbiotic relationships with mycorrhizal fungi. These beneficial soil microbes support plant health by increasing plants’ access to nutrients and water, protecting them from pathogens, improving soil properties, and more. A challenge to restoring forests on coal mined land in Appalachia is that mine soils are often degraded in a number of ways, including lacking mycorrhizal fungi, which makes mine soils difficult for trees to grow upon. Substantial improvements to coal mine reforestation success have been made since the development of the Forestry Reclamation Approach in 2005 that provides guidelines for how to create a suitable …

Exploring The Dynamics Of Bacterial Populations In The Gut Microbiota, Shaikh Obaidullah

Biology and Medicine Through Mathematics Conference

No abstract provided.

Mechanistic Examination Of Protist-Mediated Plant Growth Through The Comparative Development Of Medicago Truncatula, Shane Connolly

University Scholar Projects

Protists are known to increase plant growth through two main mechanisms: the microbial loop and the alteration of the root microbiome. The microbial loop is a nutrient recycling method in which protists provide inorganic nitrogen ions to the plant. Alteration of root microbiome leads to the removal of plant pathogens and shifting communities towards plant growth-promoting bacteria (PGPB). This study aimed to elicit which mechanism could produce the largest boost in shoot weight for Medicago truncatula. A series of microcosm experiments were explored in which M. truncatula was grown with variable microbiome structures to allow for mechanism differentiation. The …

Comparative Analysis Of Rhizosphere And Endosphere Microbiome Of Different Blueberry Species (Vaccinium Sp.), Niladri Bhowmik

Master's Theses

Blueberries are an important agricultural commodity in all over the United States. Due to its health benefits, there is a huge demand globally, thus expanding the industry. Breeding programs are essential to maintain such industries. Challenges that play a role in contemporary breeding programs are various biotic and abiotic stress factors. Studies have shown that microorganisms are recruited by plants to alleviate them during stressful conditions. Though blueberries have been cultivated for about 100 years, how the microbiome has been affected due to this is poorly understood. We hypothesized that interspecific crosses and artificial selection have significantly changed the microbiome …

Causes And Consequences Of Lasr Mutant Selection In Pseudomonas Aeruginosa Populations, Dallas L. Mould

Dartmouth College Ph.D Dissertations

Change is the only constant in life, and these changes, though random in nature, can have consequences. Quorum sensing is heterogeneous in phenotype and prone to negative selection. In P. aeruginosa, the regulator LasR is frequently non-functional in phylogenetically diverse isolates. Through repeated experimental evolution and mathematical modeling, we show that differences in growth enable lasR mutant evolutionary success and this requires a system enabling metabolic choices, known as carbon catabolite repression (or catabolite repression). The differences in catabolite repression between wild type and lasR mutants enable altered metabolite preferences, and the resulting differences in metabolic states enable intraspecies …

The Response Of Microcystis And The Microbiome To Exogenous Hydrogen Peroxide, Bryan A. Puma

Masters Theses, 2020-current

Microcystis spp. produce prolific annual blooms in freshwater systems worldwide. The success of these blooms depends heavily on the Microcystis spp. overcoming environmental factors such as oxidative stress caused by reactive oxygen species (ROS) like hydrogen peroxide. Most Microcystis genomes do not contain many genes for responding to oxidative stress, including those that encode the enzyme catalase. Other cyanobacteria such as Prochlorococcus that also lack hydrogen peroxide degrading enzymes have been shown to benefit from partnerships with heterotrophic bacteria. Microcystis spp. may also receive similar benefits from heterotrophic bacteria in the phycosphere. To test this hypothesis, we examined the …

The Effect Of Algal Wastewater Treatment Systems On Microbial Communities, Alexis Leach

University Honors Program Senior Projects

In collaboration with the Metropolitan Water Reclamation District of Greater Chicago and Gross-Wen Technologies, I examined the microbial communities in experimental tertiary wastewater treatment systems employing algal phytoremediation. Three algal phytoremediation systems were examined: two vertical conveyor belt systems, known as the 10-foot belt system and the series 4 system, and a third system lacking a converter belt in which planktonic algae grew in a control pond. I used EcoPlates to measure carbon substrate utilization by microorganisms in each system. EcoPlates contain thirty-one different carbon substrates, with a dye that indicates microbial use of each substrate. I conducted a Principal …

Elucidating Mechanisms Involved In Host Microbial-Tumor Interactions, Vidhi Chandra

Dissertations and Theses (Open Access)

Cancer is a rising cause of mortality worldwide. Microbiota is the collection of micro-organisms that live inside our bodies and can impact the host health and disease by interacting with the immune and metabolic systems. The relationship between the microbiota and cancer is complex. Gut and intratumoral microbiota can affect cancer development and progression by influencing patient outcomes and therapy responsiveness in several cancer types. Pancreatic ductal adenocarcinoma (PDAC) is an aggressive cancer surrounded by a highly immuno-suppressive tumor microenvironment (TME) which limits efficacy of most available therapies. The tumoral niche provides a privileged microenvironment for microbial colonization that can …

Gene Expression Changes Linked To Phenylpropanoid-Based Resistance To Fusarium Head Blight Of Wheat, Shiv Singla

Department of Plant Pathology: Dissertations, Theses, and Student Research

Fusarium graminearum is a devastating pathogen of wheat that causes Fusarium head blight (FHB) and contaminates the grain with the mycotoxin deoxynivalenol (DON). Resistance to FHB is quantitative and it is important to identify additional genes conferring resistance against it. The goal of this thesis was to examine if the constitutive expression of two sorghum phenylpropanoid pathway genes, SbCCoAOMT (encoding caffeoyl-CoA O-methyltransferase) and SbC3’H (encoding p-coumarate 3-hydroxylase), in the moderately-susceptible spring wheat CB037 can provide Type-I and Type-II resistance to F. graminearum and determine the underlying mechanisms of the enhanced resistance. The constitutive expression lines (CCoAOMT413, CCoAOMT421, C3H112, …

Inhibiting Survival Of Salmonella During Desiccation Through The Use Of Naturally Occurring Signals, Joseph Headrick

Electronic Theses and Dissertations

A rising problem in agriculture is the increase of antibiotic-resistant Salmonella cases associated with chicken eggs, which transmit infection to humans. To counter this, new approaches to combat Salmonella in chickens and desiccated on eggshells are vital in the prevention of human foodborne illness. Disrupting signaling pathways with naturally occurring compounds provides a potential novel avenue for prevention of Salmonella infections, as this would disrupt sensing of these environments and inhibit subsequent optimal gene expression. Starting with signals identified in previous studies, salicylic acid was found to inhibit Salmonella desiccation survival on both eggshells and plastic. To expand upon this, …

“Pinkalicious": Outer Membrane Vesicles Isolated From Pseudoalteromonas Rubra Carry Prodigiosin Antibiotics As Cargo, Margaret Hill

Senior Honors Projects

Astrangia poculata, the state coral of Rhode Island, is susceptible to infection by Vibrio coralliilyticus RE22, which is a common marine pathogen affecting various invertebrate species. The settlement of coral larvae prior to the establishment of colonies is mediated by crustose coralline algae (CCA). This process may be induced by CCA-associated protective bacteria that colonize corals in early metamorphosis; furthermore, such bacteria potentially have downstream effects in the susceptibility of corals to pathogens. Strains of Pseudoalteromonas rubra isolated from CCA have been shown to induce larval settlement of tropical corals. We hypothesize that P. rubra induces the settlement of …

Investigating The Impact Of Edaphobacter Aggregans (Wbg-1) On Arabidopsis Thaliana Development, Julia Talbert

Undergraduate Research Symposium

Acidobacteria is a phylum of bacteria that make up 50% of soil microbes. While making up a large proportion of bacteria found in soil, this phylum is largely unexplored with limited information about the bacteria and their impact on plant growth. The selected target of this study is Edaphobacter aggregans, WBG-1, which is a part of a subdivision of acidobacteria. Examining the bacteria’s effects on the development of the model plant Arabidopsis thaliana will provide insight into understanding this unknown phylum of soil-dwelling bacteria. Acidobacteria are an important realm to investigate as they affect agriculture practices. With Missouri being such …

Analysis Of Microbial Abundance On Marine Snow In The Deep Ocean, Matthew Qilan Thompson

Undergraduate University Honors Capstones

The ocean plays a critical role in the carbon cycle, with phytoplankton serving as a source of energy and nutrients (such as nitrogen and phosphorus) to larger organisms in upper trophic levels. Additionally, marine snow, a cluster of components including dead zooplankton, organic carbon debris, and polymers as carbohydrates, proteins, and DNA, transport these nutrients and associated microorganisms to the deeper parts of the ocean. However, the relationship between microbial abundance and particle sizes of marine snow across the water column is not well understood. Previous studies suggest that microbial abundance is lower in the bathypelagic zone (1,000m - 4,000m) …

A Forensic Assessment Of Current Water Quality Using Idexx Techniques In The Himmarshee Canal And New River In Fort Lauderdale, Florida, Catherine Margaret Bilodeau

All HCAS Student Capstones, Theses, and Dissertations

Fecal contamination has continued to plague local communities around the United States and the world, especially in highly populated areas like Southern Florida. Newer techniques are beginning to be used to track microbes properly as they are found in waterways. Some more recent techniques in Microbial Source Tracking (MST) use IDEXX kits to detect fecal indicator bacteria (FIB). Two IDEXX kits Colilert-18^® which detects total coliforms and Escherichia coli in water or fecal coliforms in wastewater, and Enterolert^®, which targets enterococci, were used in the waterways of the Himmarshee Canal and South Fork of the New River …