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Antibiotic Resistant Bacteria, Antibiotic Resistance Genes And Potential Drivers In The Aquatic Environments, Shuo Shen 2020 The University of Southern Mississippi

Antibiotic Resistant Bacteria, Antibiotic Resistance Genes And Potential Drivers In The Aquatic Environments, Shuo Shen

Dissertations

As antibiotic resistance genes in aquatic environment have been increasing across the world, affecting water quality and public health, many studies documented concentrations of antibiotic resistance genes and some studies discussed their potential drivers. However, systematic and quantitative reviews that link antibiotic resistance genes (ARGs) to anthropogenic and environmental factors are limited. Nevertheless, this information will be important for developing regulation policy on controlling antibiotic use and therefore reducing potential risks to antibiotic resistance. I conducted meta-analysis of ARGs concentration at a global scale using Bayesian inference to explore climatic and socio-economic factors as drivers. I found local-scale climatic variables ...


Elucidating The Molecular Pathways Involved In The Fitness And Water Stress Response Of Pseudomonas Synxantha 2-79 In The Plant Rhizosphere, Clint Henry D. Pablo 2020 University of Southern Mississippi

Elucidating The Molecular Pathways Involved In The Fitness And Water Stress Response Of Pseudomonas Synxantha 2-79 In The Plant Rhizosphere, Clint Henry D. Pablo

Master's Theses

Pseudomonas synxantha 2-79 is a biocontrol agent that represents beneficial indigenous rhizobacteria that are broadly distributed in the Pacific Northwest, USA and flourish in the rhizosphere of commercially grown wheat under surprisingly arid conditions. The molecular adaptation of 2-79-like bacteria to plants growing in dry soils is poorly understood. We hypothesized that the ability of 2-79 to colonize and persist in the rhizosphere of water-stressed plants is underpinned by the formation of hydrating biofilms and the utilization of root exudates that contain plant-derived osmoprotectants called quaternary ammonium compounds (QACs). We tested this hypothesis by identifying waters stress response pathways in ...


Beginning To Offer Drinking Water At Birth Increases The Species Richness And The Abundance Of Faecalibacterium And Bifidobacterium In The Gut Of Preweaned Dairy Calves, H. K. J. P. Wickramasinghe, J. M. Anast, S. Schmitz-Esser, N. V. L. Serão, J. A. D. R. N. Appuhamy 2020 Iowa State University

Beginning To Offer Drinking Water At Birth Increases The Species Richness And The Abundance Of Faecalibacterium And Bifidobacterium In The Gut Of Preweaned Dairy Calves, H. K. J. P. Wickramasinghe, J. M. Anast, S. Schmitz-Esser, N. V. L. Serão, J. A. D. R. N. Appuhamy

Animal Science Publications

We previously demonstrated that dairy calves having access to drinking water since birth (W0) achieved greater body weight, fiber digestibility, and feed efficiency than those that first received drinking water at 17 d of age (W17). Since gut microbiota composition could be linked to growth and development of animals, the objective of this study was to examine the effect of offering drinking water to newborn calves on composition of bacteria in the gut using a fecal microbiota analysis. Fresh feces were collected directly from the rectum of calves in W0 (n = 14) and W17 (n = 15) at 2, 6, and ...


Diatom Voucher Flora And Comparison Of Collection Methods For Biodiversity Hotspot Upper Three Runs Creek, Katie M. Johnson 2020 Georgia College & State University

Diatom Voucher Flora And Comparison Of Collection Methods For Biodiversity Hotspot Upper Three Runs Creek, Katie M. Johnson

Biology Theses

Surface freshwater is a scarce resource. Due to the scarcity and necessity of this resource, it is imperative that its quality is routinely monitored. One way of monitoring water quality is through biological assessments, which include examining algal assemblages. Regionally, little remains known of algal taxa in the southeastern United States. In the past, the Academy of Natural Sciences of Philadelphia (ANSP) conducted biological assessments along the Savannah River finding Gomphonema parvulum (Kützing) Kützing 1849 to be a dominant taxon rendering assessments inconclusive. Recent studies have provided evidence that species complexes and semi-cryptic taxa have been identified within the Gomphonema ...


The Cancer Microbiome: Distinguishing Direct And Indirect Effects Requires A Systemic View, Joao B. Xavier, Amir Mitchell 2020 Memorial Sloan-Kettering Cancer Center

The Cancer Microbiome: Distinguishing Direct And Indirect Effects Requires A Systemic View, Joao B. Xavier, Amir Mitchell

Open Access Publications by UMMS Authors

The collection of microbes that live in and on the human body - the human microbiome - can impact on cancer initiation, progression, and response to therapy, including cancer immunotherapy. The mechanisms by which microbiomes impact on cancers can yield new diagnostics and treatments, but much remains unknown. The interactions between microbes, diet, host factors, drugs, and cell-cell interactions within the cancer itself likely involve intricate feedbacks, and no single component can explain all the behavior of the system. Understanding the role of host-associated microbial communities in cancer systems will require a multidisciplinary approach combining microbial ecology, immunology, cancer cell biology, and ...


Beef Cattle That Respond Differently To Fescue Toxicosis Have Distinct Gastrointestinal Tract Microbiota, Lucas R. Koester, Daniel H. Poole, Nick V. L. Serão, Stephan Schmitz-Esser 2020 Iowa State University

Beef Cattle That Respond Differently To Fescue Toxicosis Have Distinct Gastrointestinal Tract Microbiota, Lucas R. Koester, Daniel H. Poole, Nick V. L. Serão, Stephan Schmitz-Esser

Animal Science Publications

Tall fescue (Lolium arundinaceum) is a widely used forage grass which shares a symbiosis with the endophytic fungus Epichloë coenophiala. The endophyte produces an alkaloid toxin that provides herbivory, heat and drought resistance to the grass, but can cause fescue toxicosis in grazing livestock. Fescue toxicosis can lead to reduced weight gain and milk yields resulting in significant losses to the livestock industry. In this trial, 149 Angus cows across two farms were continuously exposed to toxic, endophyte-infected, fescue for a total of 13 weeks. Of those 149 cows, 40 were classified into either high (HT) or low (LT) tolerance ...


Identification Of Antibiotic Producing Soil Bacteria Against Bacillus Subtilis, Morgan Brockhouse, Dr. Lori Scott 2020 Augustana College, Rock Island Illinois

Identification Of Antibiotic Producing Soil Bacteria Against Bacillus Subtilis, Morgan Brockhouse, Dr. Lori Scott

Identifying and Characterizing Novel Antibiotic Producing Microbes From the Soil

This project is a collaboration with the Tiny Earth Project Initiative (TEPI), which is a global network of educators and students focused on student-sourcing antibiotic discovery from soil. Individual strains of soil bacteria were isolated and produced antibiotic against Bacillus subtilis. Two of these samples were sequenced using the 16S rRNA gene to reveal they are very closely related to the genus Pseudomonas.


Survey Of Histoplasma Capsulatum In Bat Guano And Status Of Histoplasmosis In Slovenia, Central Europe, Janez Mulec, Saša Simčič, Tadeja Kotar, Romina Kofol, Sanja Stopinšek 2020 Research Centre of the Slovenian Academy of Sciences and Arts, Karst Research Institute

Survey Of Histoplasma Capsulatum In Bat Guano And Status Of Histoplasmosis In Slovenia, Central Europe, Janez Mulec, Saša Simčič, Tadeja Kotar, Romina Kofol, Sanja Stopinšek

International Journal of Speleology

There have been increasing reports on the presence of Histoplasma capsulatum in some European countries. The study investigated the presence of Histoplasma in bat guanos, speleologists with records of visiting Histoplasma-endemic regions and patients with histoplasmosis. A commercial ALPHA Histoplasma Antigen enzyme immunoassay was tested as an alternative methodology to detect Histoplasma in environment and compared with polymerase chain reaction (PCR) assays. The presence of Histoplasma antigen in bat guanos was not confirmed by PCR. Among 14 healthy speleologists, two were indicated as having the Histoplasma antigen in urine, but expressed negative PCR-specific results for the Histoplasma antigen. Five ...


Biogeographic Study Of Human Gut-Associated Crassphage Suggests Impacts From Industrialization And Recent Expansion, Tanvi P/ Honap, Krithivasan Sankaranarayanan, Stephanie L. Schnorr, Andrew T. Ozga, Christina Warinner, Cecil M. Lewis Jr. 2020 University of Oklahoma

Biogeographic Study Of Human Gut-Associated Crassphage Suggests Impacts From Industrialization And Recent Expansion, Tanvi P/ Honap, Krithivasan Sankaranarayanan, Stephanie L. Schnorr, Andrew T. Ozga, Christina Warinner, Cecil M. Lewis Jr.

Anthropology Faculty Publications

CrAssphage (cross-assembly phage) is a bacteriophage that was first discovered in human gut metagenomic data. CrAssphage belongs to a diverse family of crAss-like bacteriophages thought to infect gut commensal bacteria belonging to Bacteroides species. However, not much is known about the biogeography of crAssphage and whether certain strains are associated with specific human populations. In this study, we screened publicly available human gut metagenomic data from 3,341 samples for the presence of crAssphage sensu stricto (NC_024711.1). We found that crAssphage prevalence is low in traditional, hunter-gatherer populations, such as the Hadza from Tanzania and Matses from Peru, as ...


Microbial Responses To Unconventional Oil And Gas Development May Alter Ecosystem Function In Headwater Streams, Rachel Michaels 2020 West Virginia University

Microbial Responses To Unconventional Oil And Gas Development May Alter Ecosystem Function In Headwater Streams, Rachel Michaels

Graduate Theses, Dissertations, and Problem Reports

The demand for natural gas, and the need for efficient extraction, has led to the development of unconventional oil and natural gas (UOG) techniques. Due to the novelty of UOG, the potential impacts to freshwater ecosystems are not fully understood. We used a dual pronged approach to study the effects of UOG development on microbial biodiversity and function via a laboratory microcosm experiment and a survey study of streams with and without UOG development within their watersheds. The laboratory microcosm study simulated stream contamination with produced water, a byproduct of UOG operation, using sediment collected from one high water-quality stream ...


Massard Prairie Restoration And Soil Microbiome Succession, Jeffrey M. Shaver, Emily S. Bellis, Chizuko Iwaki, Jake Qualls, Jay Randolph, Jeremiah Smith 2020 University of Arkansas, Fort Smith

Massard Prairie Restoration And Soil Microbiome Succession, Jeffrey M. Shaver, Emily S. Bellis, Chizuko Iwaki, Jake Qualls, Jay Randolph, Jeremiah Smith

Journal of the Arkansas Academy of Science

We have initially sequenced soil microbial DNA from 4 restored and 4 virgin tallgrass prairie soil samples from Ben Geren Park and Massard Prairie (Fort Smith, AR), respectively. As expected, the soil microbiomes are distinct, with several lineages of nitrogen-fixing bacteria more common in virgin tall grass prairie. However, we predict that as restoration of tallgrass prairie in Ben Geren Park progresses, the soil microbiome of restored prairie will more closely mirror those of the virgin prairie.


From Pools To Flow: The Promise Framework For New Insights On Soil Carbon Cycling In A Changing World, Bonnie G. Waring, Benjamin N. Sulman, Sasha Reed, A. Peyton Smith, Colin Averill, Courtney A. Creamer, Daniela F. Cusack, Steven J. Hall, Julie D. Jastrow, Andrea Jilling, Kenneth M. Kemner, Markus Kleber, Xiao-Jun Allen Liu, Jennifer Pett-Ridge, Marjorie Schulz 2020 Utah State University

From Pools To Flow: The Promise Framework For New Insights On Soil Carbon Cycling In A Changing World, Bonnie G. Waring, Benjamin N. Sulman, Sasha Reed, A. Peyton Smith, Colin Averill, Courtney A. Creamer, Daniela F. Cusack, Steven J. Hall, Julie D. Jastrow, Andrea Jilling, Kenneth M. Kemner, Markus Kleber, Xiao-Jun Allen Liu, Jennifer Pett-Ridge, Marjorie Schulz

Ecology, Evolution and Organismal Biology Publications

Soils represent the largest terrestrial reservoir of organic carbon, and the balance between soil organic carbon (SOC) formation and loss will drive powerful carbon‐climate feedbacks over the coming century. To date, efforts to predict SOC dynamics have rested on pool‐based models, which assume classes of SOC with internally homogenous physicochemical properties. However, emerging evidence suggests that soil carbon turnover is not dominantly controlled by the chemistry of carbon inputs, but rather by restrictions on microbial access to organic matter in the spatially heterogeneous soil environment. The dynamic processes that control the physicochemical protection of carbon translate poorly to ...


Genetic And Biochemical Characterization Of Ergot Alkaloid Synthesizing Fungi And Their Symbionts, Matthew Duane Maust 2020 West Virginia University

Genetic And Biochemical Characterization Of Ergot Alkaloid Synthesizing Fungi And Their Symbionts, Matthew Duane Maust

Graduate Theses, Dissertations, and Problem Reports

Ergot alkaloids are fungal tryptophan derived toxins which affect mammalian circulation and neurotransmission. These compounds are biosynthesized by a conserved genetic pathway, known as the ergot alkaloid synthesis (EAS) pathway by fungi belonging to the ascomycete families Trichocomaceae and Clavicipitaceae. Several Ipomoea species and related plants in the morning glory family harbor vertically transmitted symbiotic fungi in the genus Periglandula, also members of Clavicipitaceae, that produce ergot alkaloids. Metabolomic analysis of seeds identified a previously uncharacterized glycoside form of the pharmaceutically important ergot alkaloid, ergonovine. Several species belonging to the fungal genus Metarhizium have recently been shown to have the ...


The Host Gatekeeper: Using The Flagellar Pathway To Understand Symbiont Host Adaptation, Adam R. Pollio 2020 West Virginia University

The Host Gatekeeper: Using The Flagellar Pathway To Understand Symbiont Host Adaptation, Adam R. Pollio

Graduate Theses, Dissertations, and Problem Reports

The acquisition of microbial partners is a strategy used by a diverse group of arthropods to overcome ecological barriers that might normally make certain niches uninhabitable. The unique phylogenetic opportunities attainable from the natural experiment of the Sodalis-allied clade allow for better understanding of how molecular structures evolve through time. Here, we focus on the evolution of the flagellar synthesis pathway, due to its complexity and ability to diverge in response to ecological pressures. We used this molecular pathway and natural experiment to show that normal evolutionary outcomes associated with symbiosis (i.e., genome reduction) do not explain the predicted ...


The Effects Of Staining Cyanobacteria With Sytoxgreen After Lysis By Freeze-Thaw And Lysis By Ethanol, Samantha Galambos 2020 The University of Akron

The Effects Of Staining Cyanobacteria With Sytoxgreen After Lysis By Freeze-Thaw And Lysis By Ethanol, Samantha Galambos

Williams Honors College, Honors Research Projects

The purpose of this project is to find the effects of staining toxic cyanobacteria with SYTOXGreen after lysis by freeze-thaw and lysis by ethanol. This project will focus on two strains of toxic cyanobacteria known as Aphanizomenon - A. flos-aquae and Planktothrix - P. agardhii. The live and dead cells are observed under blue and red fluorescent light to show the effectiveness of each lysis. It is important that this topic is researched because it is significantly affecting our waterways and sometimes drinking water. We often see that you cannot swim in Lake Erie due to algae, more specifically, these algae. We ...


Determination Of Iron-Reducing Bacterial Activities In Lake Sediments., Alexandra Kahn 2020 The University of Akron

Determination Of Iron-Reducing Bacterial Activities In Lake Sediments., Alexandra Kahn

Williams Honors College, Honors Research Projects

Algal blooms are growing rampantly in lacustrine systems due to an increase of phosphorus, a nutrient for algae. Phosphorus is being released into the environment causing overpopulation and eutrophication which damages the ecosystem. The availability of phosphorus is affected by the solubility of iron which is regulated through iron reducing and iron oxidizing bacteria. Phosphorus adheres to insoluble Fe(III), which prohibits algae from utilizing it, while phosphorus does not attach to soluble Fe(II) and therefore it remains available to algae. The purpose of this study was to determine how bacteria influence iron solubility and what are the ideal ...


Comparison Of Fe(Iii) Reduction Rates By Iron-Reducing Bacteria Within Sub Muros Samples From Quadrilátero Ferrífero Iron-Ore Caves, Brazil, Summer Ellis 2020 The University of Akron

Comparison Of Fe(Iii) Reduction Rates By Iron-Reducing Bacteria Within Sub Muros Samples From Quadrilátero Ferrífero Iron-Ore Caves, Brazil, Summer Ellis

Williams Honors College, Honors Research Projects

Previous research investigating the speleogenesis of iron-ore caves (IOC) in the Quadrilátero Ferrífero, or “Iron Quadrangle,” of Brazil suggests that microbial iron reduction and subsequent dissolution of the surrounding Fe(III) rich rocks is responsible for cave formation. A soft intra-wall substance (sub muros) containing iron-reducing bacteria (FeRB) was discovered underneath the durable crusts of cave walls. The goal of the study was to determine if reduction rates were comparable between sub muros samples, while additionally observing how different electron donors affect microbial iron reduction. To do this, I compared Fe(III) reduction rates between sub muros samples collected from ...


Biocide Resistance As A Result Of Exposure To Biocides Used In Hydraulic Fracturing, Lindsey Schenten 2020 Michigan Technological University

Biocide Resistance As A Result Of Exposure To Biocides Used In Hydraulic Fracturing, Lindsey Schenten

Dissertations, Master's Theses and Master's Reports

Microbial resistance to antimicrobials is an important topic to investigate not only for our health but for the environment. There is a growing concern about expanding microbial resistance to both antibiotics and other antimicrobials such as biocides. We wanted to know how bacteria previously exposed to hydraulic fracturing fluids, including biocides, would react to biocide exposure and what the mechanism of resistance looked like. In order to test this hypothesis bacterial isolates were obtained from water and sediment from a stream that had been previously exposed to a spill of hydraulic fracturing water. Thirty bacterial isolates were obtained from these ...


Isothermal Environmental Heat Energy Utilization By Transmembrane Electrostatically Localized Protons At The Liquid-Membrane Interface, James Weifu Lee 2020 Old Dominion University

Isothermal Environmental Heat Energy Utilization By Transmembrane Electrostatically Localized Protons At The Liquid-Membrane Interface, James Weifu Lee

Chemistry & Biochemistry Faculty Publications

This study employing the latest theory on transmembrane electrostatic proton localization has now, for the first time, consistently elucidated a decades-longstanding bioenergetic conundrum in alkalophilic bacteria and more importantly discovered an entirely new feature: isothermal environmental heat utilization by electrostatically localized protons at the liquid-membrane interface. It was surprisingly revealed that the protonic motive force (equivalent to Gibbs free energy) from the isothermal environmental heat energy utilization through the electrostatically localized protons is not constrained by the overall energetics of the redox-driven proton pump system because of the following: (a) the transmembrane electrostatically localized protons are not free to move ...


Microbial Degradation Of Urea Oligomers: Potential Slow Release Nitrogen Fertilizers, Maddy Bygd 2020 Hamline University

Microbial Degradation Of Urea Oligomers: Potential Slow Release Nitrogen Fertilizers, Maddy Bygd

Departmental Honors Projects

Urea is the most commonly used nitrogen compound in fertilizers across the world. It provides the most nitrogen at the lowest cost. However, with the size and solubility of this compound, it is easily washed out of the soil. This results in the need to continuously add fertilizer to fields, creating adverse effects on the environment due to nitrogen runoff and leading to increased expenses for farmers. Triuret, a urea oligomer, is a compound with promising potential for use as a nitrogen source, providing a slower release of nitrogen into the soil. It is hypothesized that this compound can be ...


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