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Identification And Analysis Of Feather Degrading Bacteria: A Search For Keratinase Genes, Nehal Navali 2020 University of Connecticut

Identification And Analysis Of Feather Degrading Bacteria: A Search For Keratinase Genes, Nehal Navali

Honors Scholar Theses

Over two million tons of feather waste is generated annually by the poultry industry, the majority of which goes into landfills due to the difficulty of degrading its major component keratin. Although a portion of feather waste is eliminated via incineration or chemical treatment, the use of Feather Degrading Bacteria (FDB) has been proposed as a cheap and eco-friendly alternative. FDBs have been consistently isolated from the feather microbiome of birds and contain genes coding for the specialized protein keratinase which is able to degrade feathers. By doing so, feather waste, which is rich in nutrients, can be repurposed as …


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 …


A Comparative Taxonomic And Diversity Study Of Litter-Associated Fungi In Northwest Arkansas Forests, Rajaa Abdulrazzaq Abbas Al Aanbagi 2020 University of Arkansas, Fayetteville

A Comparative Taxonomic And Diversity Study Of Litter-Associated Fungi In Northwest Arkansas Forests, Rajaa Abdulrazzaq Abbas Al Aanbagi

Graduate Theses and Dissertations

Fungi are taxonomically the most species-rich group of organisms on the earth, ecologically occupy distinctive niches and interact with diverse other organisms throughout their biogeographic distributions and functionally play key roles through their various lifestyles. Plant litter, in particular, is a keystone component in ecosystems and provides heterogeneous microhabitats for the often overlooked litter-decomposing fungi and other organisms on the floor of temperate deciduous forests. Litter fungi involve indirect interactions with the plant, soil and whole food web network. However, the community structure and functions of litter-associated fungi as well as patterns of species richness distributed across various litter microhabitats …


The Release, Transport, And Utilization Of Phosphorus From Bed-Sediments: A Study Of A Eutrophic Littoral Cove On Beaver Lake In Northwest Arkansas, James A. McCarty 2020 University of Arkansas, Fayetteville

The Release, Transport, And Utilization Of Phosphorus From Bed-Sediments: A Study Of A Eutrophic Littoral Cove On Beaver Lake In Northwest Arkansas, James A. Mccarty

Graduate Theses and Dissertations

Eutrophication of surface waters not only impacts the environment but also water treatment processes, the most significant of which is from the effects of algae. During peak algal growth in many southern U.S. reservoirs, inflows that bring nutrients are at an annual minimum, and phosphorus released from bed-sediments is trapped in the hypolimnion. Littoral areas, described as the most productive zone of the lake, may be a possible source of phosphorus that fuels algal growth in the reservoir. I studied an isolated shallow cove in the War Eagle Creek arm of Beaver Lake in Northwest Arkansas to measure, quantify, and …


Comparison Of Three Analytical Techniques For General Characterisation Of Selected Algae And Cyanobacteria, Mohamed Iqbal Suhaina Nashath 2020 Universiti Malaya

Comparison Of Three Analytical Techniques For General Characterisation Of Selected Algae And Cyanobacteria, Mohamed Iqbal Suhaina Nashath

Student Works (2020-2029)

Algae and cyanobacteria maintain the oxygenation of earth, and are utilised as biofuels, biofertilizers and nutrition feed. The characterisation of algae and cyanobacteria through conventional methods require technical expertise, laborious sample preparation, and moderately expensive instruments and reagents. Hence, in this study, selected bioanalytical techniques with minimal sample preparation were incorporated, to simplify the characterisation of algae and cyanobacteria. The objectives of this research were to study the phylogenetic relationship of the selected algae and cyanobacteria via the 23S plastid ribosomal ribonucleic acid (rRNA) and 18S rRNA biomarkers; to validate the presence of the microcystin synthetase (mcy) gene cluster encoding …


Effect Of Zinc On Microcystis Aeruginosa And Its Toxin Production, Jose L. Perez 2020 Seton Hall University

Effect Of Zinc On Microcystis Aeruginosa And Its Toxin Production, Jose L. Perez

Seton Hall University Dissertations and Theses (ETDs)

Cyanobacteria harmful algal blooms (CHABs) are globally increasing biomasses of detrimental cyanobacteria due to anthropogenic water phosphorous and nitrogen loading and climate change. CHABs often produce secondary metabolites, cyanotoxins, that cause harmful effects to organisms, most water systems, and socioeconomic infrastructures. Additionally, the presence of heavy metal pollutant runoff in CHAB affected environments may result in CHAB population changes – aggravating toxigenicity. Zinc metal resistance and stress response were studied in microcystin (MC) cyanotoxin-producing Microcystis aeruginosa UTEX LB 2385 (M. aeruginosa UTEX LB 2385) and non-MC producing Microcystis aeruginosa UTEX LB 2386 (M. aeruginosa UTEX LB 2386) cyanobacteria. Molecular analysis …


Investigation Of An Elevational Gradient Reveals Strong Differences Between Bacterial And Eukaryotic Communities Coinhabiting Nepenthes Phytotelmata, Kadeem J. Gilbert, Leonora S. Bittleston, Mark Arcebal K. Naive, Anthony E. Kiszewski, Perry Archival C. Buenavente, David J. Lohman, Naomi E. Pierce 2020 Harvard University

Investigation Of An Elevational Gradient Reveals Strong Differences Between Bacterial And Eukaryotic Communities Coinhabiting Nepenthes Phytotelmata, Kadeem J. Gilbert, Leonora S. Bittleston, Mark Arcebal K. Naive, Anthony E. Kiszewski, Perry Archival C. Buenavente, David J. Lohman, Naomi E. Pierce

Publications and Research

Elevation is an important determinant of ecological community composition. It integrates several abiotic features and leads to strong, repeatable patterns of community structure, including changes in the abundance and richness of numerous taxa. However, the influence of elevational gradients on microbes is understudied relative to plants and animals. To compare the influence of elevation on multiple taxa simultaneously, we sampled phytotelm communities within a tropical pitcher plant (Nepenthes mindanaoensis) along a gradient from 400 to 1200 m a.s.l. We use a combination of metabarcoding and physical counts to assess diversity and richness of bacteria, micro-eukaryotes, and arthropods, and compare the …


Microbiota Accessible Carbohydrates And Susceptibility To Clostridioides Difficile Infection, Keegan Schuchart, Jennifer Auchtung, Thomas Auchtung 2020 University of Nebraska-Lincoln

Microbiota Accessible Carbohydrates And Susceptibility To Clostridioides Difficile Infection, Keegan Schuchart, Jennifer Auchtung, Thomas Auchtung

UCARE: Research Products

This experiment looked into the effects of dietary microbiota accessible carbohydrates (MACs)on the composition of human GI microbe colonies and their susceptibility to pathogen infection. Three different concentrations of MAC ingrained media were tested in mini bioreactor arrays, treated with antibiotics, infected with Clostridioides difficile, then allowed to recover. Microbe community was examined for strain composition and diversity before and after the antibiotic treatment and Clostridioides difficile infection. After the initial mini bioreactor run, individual isolates were investigated in their ability to respond to specific MACs Arabinoglactina, Inulin, and Soluble starch at experimental concentrations.


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 …


Quantifying Nutrient Throughput And Dom Production By Algae In Continuous Culture, Anne Willem Omta 2020 Case Western Reserve University

Quantifying Nutrient Throughput And Dom Production By Algae In Continuous Culture, Anne Willem Omta

Faculty Scholarship

Freshwater and marine algae can balance nutrient demand and availability by regulating uptake, accumulation and exudation. To obtain insight into these processes under nitrogen (N) and phosphorus (P) limitation, we reanalyze published data from continuous cultures of the chlorophyte Selenastrum minutum . Based on mass budgets, we argue that much of the non-limiting N and P had passed through the organisms and was present as dissolved organic phosphorus or nitrogen (DOP or DON). We construct a model that describes the production of biomass and dissolved organic matter (DOM) as a function of the growth rate. A fit of this model …


Abundance And Distribution Of Microplastics And Persistent Organic Pollutants In Selected Rivers Of Peninsular Malaysia, Anuar Norkhairiyah 2020 Universiti Malaya

Abundance And Distribution Of Microplastics And Persistent Organic Pollutants In Selected Rivers Of Peninsular Malaysia, Anuar Norkhairiyah

Student Works (2020-2029)

Nearly 70 to 80 percent of microplastics are believed to be transported to the sea through rivers. Yet, less attention has been given to the accumulation of microplastics in the freshwater environment. They are emerging anthropogenic contaminants on account of their potential to adsorb and/or release POPs from and/or to the surrounding environment, and become the vector transferring these pollutants from water to the food web. This study is aimed to explore the abundance and distribution of microplastics and POPs in six rivers of Peninsular Malaysia, which comprised of three rivers from the West Coast (Sepetang River, Serkam River, and …


Hydrolysis Of Palm Oil Mill Effluent Using Enzymes From Spent Mushroom Substrate Of Pleurotus Pulmonarius (Fr.) Quel, Mat Yunan Nurul Anisa 2020 Universiti Malaya

Hydrolysis Of Palm Oil Mill Effluent Using Enzymes From Spent Mushroom Substrate Of Pleurotus Pulmonarius (Fr.) Quel, Mat Yunan Nurul Anisa

Student Works (2020-2029)

Mushroom cultivation and palm oil industry in Malaysia have contributed to the large volumes of lignocellulosic residues. Lignocellulolytic enzymes profiles (lignin peroxidase, laccase, xylanase, endoglucanase, and β-glucosidase) of Pleurotus pulmonarius (parents strains UMP001 and UMP 002, and the hybrid UMH004) during growth in sawdust substrate bags were investigated. The enzymes extracted from the spent mushroom substrate (SMS) of the strain with the highest enzymes productivity was used to hydrolyse palm oil mill effluent (POME). Optimization of parameters for POME hydrolysis to release reducing sugar was conducted using central composite design (CCD) of response surface methodology (RSM). The potential of hydrolysed …


Biogeographic Patterns In Members Of Globally Distributed And Dominant Taxa Found In Port Microbial Communities., Ryan B Ghannam, Laura G. Schaerer, Timothy M. Butler, Stephen M Techtmann 2020 Michigan Technological University

Biogeographic Patterns In Members Of Globally Distributed And Dominant Taxa Found In Port Microbial Communities., Ryan B Ghannam, Laura G. Schaerer, Timothy M. Butler, Stephen M Techtmann

Michigan Tech Publications, Part 1

We conducted a global characterization of the microbial communities of shipping ports to serve as a novel system to investigate microbial biogeography. The community structures of port microbes from marine and freshwater habitats house relatively similar phyla, despite spanning large spatial scales. As part of this project, we collected 1,218 surface water samples from 604 locations across eight countries and three continents to catalogue a total of 20 shipping ports distributed across the East and West Coast of the United States, Europe, and Asia to represent the largest study of port-associated microbial communities to date. Here, we demonstrated the utility …


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 Research

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 compared to …


Biotic And Abiotic Factors Influencing Arsenic Biogeochemistry And Toxicity In Fluvial Ecosystems: A Review, Laura Barral-Fraga, María Teresa Barral, Keeley L. MacNeill, Diego Martiñá-Prieto, Soizic Morin, María Carolina Rodríguez-Castro, Baigal-Amar Tuulaikhuu, Helena Guasch 2020 Universitat de Girona

Biotic And Abiotic Factors Influencing Arsenic Biogeochemistry And Toxicity In Fluvial Ecosystems: A Review, Laura Barral-Fraga, María Teresa Barral, Keeley L. Macneill, Diego Martiñá-Prieto, Soizic Morin, María Carolina Rodríguez-Castro, Baigal-Amar Tuulaikhuu, Helena Guasch

School of Natural Resources: Faculty Publications

This review is focused on the biogeochemistry of arsenic in freshwaters and, especially, on the key role that benthic microalgae and prokaryotic communities from biofilms play together in through speciation, distribution, and cycling. These microorganisms incorporate the dominant iAs (inorganic arsenic) form and may transform it to other arsenic forms through metabolic or detoxifying processes. These transformations have a big impact on the environmental behavior of arsenic because different chemical forms exhibit differences in mobility and toxicity. Moreover, exposure to toxicants may alter the physiology and structure of biofilms, leading to changes in ecosystem function and trophic relations. In this …


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.


Investigating Links Between Soil Microbial Structure And Function In Three Major Plant Communities Across Temporal Scales Of Arctic Alaska, Kaj Lynoe 2020 South Dakota State University

Investigating Links Between Soil Microbial Structure And Function In Three Major Plant Communities Across Temporal Scales Of Arctic Alaska, Kaj Lynoe

Electronic Theses and Dissertations

Arctic microbial systems continue to get attention today as our understanding regarding their structure and function in a changing system is paramount to C feedbacks with warming and changes in precipitation. Plant communities and microbial community processes across the Arctic landscape are central to understanding tundra ecosystem processes because environmental conditions and plant community structure drive microbial cycling of soil organic matter. Here, we want to understand how soil microbial respiration, mineralization, biomass, and community composition are linked to three Alaskan tundra plant communities, namely Shrub, Tussock, and Sedge tundra and the seasonal variability in this system. A total of …


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