Open Access. Powered by Scholars. Published by Universities.®

Environmental Microbiology and Microbial Ecology Commons™

Open Access. Powered by Scholars. Published by Universities.®

Biology

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 61 - 90 of 225

Full-Text Articles in Environmental Microbiology and Microbial Ecology

Biomass Estimation Of Marine Biofilms On Plastic Surfaces, Kian Banihashemi, Fernando Javier Gil Jun 2022

Biomass Estimation Of Marine Biofilms On Plastic Surfaces, Kian Banihashemi, Fernando Javier Gil

Biological Sciences

Plastics have become a major source of marine pollution, which threatens food safety and quality, human health, and marine ecosystems. Due to the drastic negative effects of plastics in a marine environment, alternative biodegradable plastics are being generated that are more eco-friendly and have less environmental impact. Though some of these plastics are known to biodegrade, the process of degradation for bioplastics has not been heavily studied in a marine environment. This pilot project sought to both quantify the process of biodegradation and compare across different methods for effectiveness of biomass estimation, which serves as an indicator of biodegradation. Plastics …

Go to article

Detecting Potentially Neurotoxic Pseudo-Nitzschia Species In The Grand Strand Area, Chesney Price May 2022

Detecting Potentially Neurotoxic Pseudo-Nitzschia Species In The Grand Strand Area, Chesney Price

Honors Theses

Pseudo-nitzschia is a globally distributed diatom genus which contains 26 neurotoxin (domoic-acid) producing species. In shallow coastal waters these diatoms are associated with both the development of harmful algal blooms and the bio-accumulation of toxins in shellfish that can impact human health. Pilot data recovered in 2018 indicated the presence of multiple species of Pseudo-nitzschia, including domoic-acid producing taxa. We hypothesize that we will recover a similar species diversity using multiple sampling dates during the summer of 2021. Environmental DNA (eDNA) samples taken from the public shellfish harvesting area waters at Huntington Beach State Park (SC) over a two month …

Go to article

Effect Of Mycorrhizae Inoculation On The Growth And Success Of Three Taxodium Distichum Hybrids In Saline - Impacted Coastal Soils, Elif Ilhan May 2022

Effect Of Mycorrhizae Inoculation On The Growth And Success Of Three Taxodium Distichum Hybrids In Saline - Impacted Coastal Soils, Elif Ilhan

Electronic Theses and Dissertations

In 2008, Galveston Island was severely impacted by Hurricane Ike, resulting in high salt deposition in the soil and groundwater. This caused a loss of many native plant species. A study was initiated to determine effective ways to promote the growth conditions of three bald cypress genotypes (Taxodium distichum var distichum and Taxodium distichum var mexicanum crosses) in salt-affected soils. The treatments applied were mycorrhizae inoculation, fertilizer application, and a combination of mycorrhizae inoculation and fertilizer application. A total of sixty (60) trees planted in plots of three rows and divided into five randomized replication blocks of four treatments …

Go to article

An Analysis Of The Effects Of Temperature And Other Environmental Factors On Microorganismal Productivity Within Aquatic Ecosystems Using Long-Term Data From Various Lter And Ilter Sites, Andrew Dorbu May 2022

An Analysis Of The Effects Of Temperature And Other Environmental Factors On Microorganismal Productivity Within Aquatic Ecosystems Using Long-Term Data From Various Lter And Ilter Sites, Andrew Dorbu

Theses and Dissertations

Global climate change is a phenomenon resulting in more extreme weather patterns and species diversity loss. In this study, I explore the impacts of climate change on regional patterns of microbial productivity. Variation in microbial productivity was explained using temperature, salinity, and dissolved oxygen as predictors in regression models with data from the LTER and iLTER network of sites that ranged from the poles to the equator. I found a positive relationship between temperature and productivity. Antarctica and Arctic sites exhibited the strongest positive relationships supporting prior research demonstrating temperature as one of the driving forces of productivity change in …

Go to article

Temporal And Spatial Comparison Of Pseudo-Nitzschia Species Composition And Domoic Acid In Narragansett Bay, Rhode Island And The Northeast U.S. Shelf, Isabella Church, Bethany D. Jenkins May 2022

Temporal And Spatial Comparison Of Pseudo-Nitzschia Species Composition And Domoic Acid In Narragansett Bay, Rhode Island And The Northeast U.S. Shelf, Isabella Church, Bethany D. Jenkins

Senior Honors Projects

Diatoms are unicellular algae that make up a significant portion of phytoplankton biomass at the base of marine food webs. Narragansett Bay (NB), RI is home to several species of the diatom genus Pseudo-nitzschia (P-n), some of which are known to cause harmful algal blooms through the production of the potent neurotoxin domoic acid (DA). This toxin can lead to Amnesic Shellfish Poisoning in humans through the consumption of affected shellfish. Although the presence of P-n has been well established in NB for over 50 years, DA levels have only recently become a problem, with shellfish harvest closures …

Go to article

Alterations Of The Gut Mycobiome In Patients With Ms - A Bioinformatic Approach, Saumya Shah May 2022

Alterations Of The Gut Mycobiome In Patients With Ms - A Bioinformatic Approach, Saumya Shah

Honors Scholar Theses

The mycobiome is the fungal component of the gut microbiome and is implicated in several autoimmune diseases. However, its role in multiple sclerosis (MS) has not been studied. We performed descriptive and formal statistical tests using the R language to characterize the gut mycobiome in people with MS (pwMS) and healthy controls. We found that the microbiome composition of multiple sclerosis patients is different from healthy people. The mycobiome had significantly higher alpha diversity and inter-subject variation in pwMS than controls. Additionally, Saccharomyces and Aspergillus were over-represented in pwMS. Different mycobiome profiles, defined as mycotypes, were associated with different bacterial …

Go to article

Assessing Environmental Factors That Influence Cyanobacterial Blooms In Skinn Lake, Kloe Atwood Apr 2022

Assessing Environmental Factors That Influence Cyanobacterial Blooms In Skinn Lake, Kloe Atwood

Honors Projects

Global lakes are experiencing an increase in toxic algal blooms that can be damaging to the environment. These blooms are caused by cyanobacteria, specifically a species called Planktothrix. Skinn Lake, in Ohio, is a location of a cyanobacterial bloom that is mainly populated by Planktothrix rubescens. This lake was further examined to identify the major toxin-producing bacteria and identify environmental microbes surrounding the bloom. When the data was examined it was found that the microbiomes of the lake greatly differed between the winter (bloom) months and the summer (non-bloom) months. This difference can be viewed within the nutrient analysis from …

Go to article

Composting During Winter Versus Summer: A Microbial Analysis, Madison Ochs Apr 2022

Composting During Winter Versus Summer: A Microbial Analysis, Madison Ochs

Honors Theses

Pre-consumer food waste, hay, and woodchips were composted using two different methods of static composting: forced aeration (FA) and natural aeration (NA). The composting process was performed during the winter and summer for 106 and 124 days, respectively. The composting process for both winter and summer processes did not reach the temperature above the 40°C threshold of the thermophilic stage in composting. The microbial communities present during different timepoints (start, peak, and final) along the composting process were analyzed with DNA sequencing techniques and visualized using QIIME 2, an open-source bioinformatics platform. The microbial communities of the winter and summer …

Go to article

Microbial Diversity And Community Structure In Sediments Associated With The Seagrass (Thallassia Testudinum) In Apalachicola Bay, Florida, Rahma Ahmed, Thomas Mcelroy, Troy Mutchler Apr 2022

Microbial Diversity And Community Structure In Sediments Associated With The Seagrass (Thallassia Testudinum) In Apalachicola Bay, Florida, Rahma Ahmed, Thomas Mcelroy, Troy Mutchler

Symposium of Student Scholars

Seagrass is an angiosperm which provides many ecosystem services in coastal areas, such as providing food, shelter and nurseries for many species, and decreasing the impact of waves on shorelines. A global assessment reported that 29% of known seagrass meadows are in a state of decline due to the effects of human activity. Seagrass is commonly found in shallow marine waters where they form meadows containing a microbiome that plays an important role in providing nutrients for seagrass growth, though little is known about the microorganisms within the seagrass meadow sediments. Our project collected sediments from seagrass meadows and adjacent …

Go to article

Analysis And Identification Of Lipolytic Bacterial Species For The Degradation Of Wastewater Lipids, Lindsay C. Smoak Apr 2022

Analysis And Identification Of Lipolytic Bacterial Species For The Degradation Of Wastewater Lipids, Lindsay C. Smoak

Honors College Theses

The aim of this study was to isolate native bacterial strains from the wastewater treatment facilities of Statesboro, GA to identify their lipolytic activities. Obtained bacterial strains were further assessed via morphological and biochemical methods to determine their enzymatic capabilities. Use of the detergent Tween-20 in growth mediums was the first criteria to assess lipase activity, and these isolates were further investigated to quantitatively measure lipase presence and activity. Lipase protein was precipitated and dialyzed to perform a lipase activity assay, followed by Sodium Dodecyl Sulphate–Polyacrylamide Gel Electrophoresis (SDS-PAGE) to confirm the presence of the lipolytic enzymes. Sanger sequencing was …

Go to article

Developing An Electroporation Method For Transforming Streptomyces Nymphaeiformis, Heather Knott, Stephen Baron Apr 2022

Developing An Electroporation Method For Transforming Streptomyces Nymphaeiformis, Heather Knott, Stephen Baron

Honors Projects

Streptomyces species are notoriously difficult to transform. Streptomyces nymphaeiformis is no different, so a method of electroporation was used to attempt to transform the cells. Multiple growth stages were used in order to alter the degree of development of the cell wall. The procedure did not kill the cells, but the cells were not transformed. Due to the lack of transformation with S. nymphaeiformis, transformation was attempted on two other Streptomyces strains, S. lividans and S. coelicolor. Neither was successfully transformed to thiostrepton (tsr) resistance, nor did they grow on a plate lacking thiostrepton. One possibility for the …

Go to article

Prevalence Of Bacillus Licheniformis On Northern Saw-Whet Owls (Aegolius Acadicus), Lauren Benedict Apr 2022

Prevalence Of Bacillus Licheniformis On Northern Saw-Whet Owls (Aegolius Acadicus), Lauren Benedict

Senior Honors Theses

Birds are hosts to a variety of bacteria and fungi including some that are keratinolytic. These feather degrading bacteria, including Bacillus licheniformis, are capable of degrading β-keratin which is a major component of feathers. While there is little evidence to indicate that feather degrading bacteria are capable of degrading feathers on live birds, there is ample evidence to indicate that many bird species experience altered feather coloration. There is significant variation in the reported prevalence of B. licheniformis on birds with percentages ranging from 6.7% to 99%. This study sought to provide further support for an overall prevalence of …

Go to article

Ohio Anuran Gut Microbiomes, Serena Hoffman Mar 2022

Ohio Anuran Gut Microbiomes, Serena Hoffman

Undergraduate Honors Thesis Projects

Recent studies focusing on the skin and gut microbiome of vertebrates have found how important microbiomes are to maintaining host health. Understanding the role the gut microbiome plays to host health is of great importance for conservation. Less is known about the gut microbiome than the skin microbiome for amphibians. Literature is especially lacking for local Ohio anuran species. The purpose of this study was to establish the baseline composition of the gut microbiome for local Ohio anurans and to determine whether host species or habitat is the best predictor of gut microbiome composition. Tadpoles were collected from seven different …

Go to article

Microbiological Contamination Associated With The Proximity Of A Refuse Dumpsite To A River Situated In Okada, Edo State, Nigeria, Ebere J. Okafor-Elenwo, Odaro S. Imade, Osazee E. Izevbuwa Mar 2022

Microbiological Contamination Associated With The Proximity Of A Refuse Dumpsite To A River Situated In Okada, Edo State, Nigeria, Ebere J. Okafor-Elenwo, Odaro S. Imade, Osazee E. Izevbuwa

Journal of Bioresource Management

This study was performed to evaluate the potential contamination of the Okponha river situated near a dumpsite in Okada, Edo State, Nigeria. Water samples were collected and analyzed for bacteriological and parasitological quality using standard procedures. Isolation and enumeration of bacterial colonies were performed by pour plate technique and the isolated bacteria were identified by standard phenotypic tests. Helminths and protozoa were screened by the direct smear technique. The values of HPC (3.79 ± 0.12 log10 CFU/ml) and TCC (2.20 ± 0.14 log10 CFU/ml) obtained from the river water samples exceeded WHO and NAFDAC recommended limits (≤ 2 …

Go to article

The Coxsackievirus And Adenovirus Receptor Has A Short Half-Life In Epithelial Cells, Poornima Kotha Lakshmi Narayan, James M. Readler, Mahmoud S. Alghamri, Trisha L. Brockman, Ray Yan, Priyanka Sharma, Vladislav Snitsarev, Katherine J.D.A Excoffon, Abimbola O. Kolawole Jan 2022

The Coxsackievirus And Adenovirus Receptor Has A Short Half-Life In Epithelial Cells, Poornima Kotha Lakshmi Narayan, James M. Readler, Mahmoud S. Alghamri, Trisha L. Brockman, Ray Yan, Priyanka Sharma, Vladislav Snitsarev, Katherine J.D.A Excoffon, Abimbola O. Kolawole

Department of Biology Faculty Scholarship and Creative Works

The coxsackievirus and adenovirus receptor (CAR) is an essential cellular protein that is involved in cell adhesion, cell signaling, and viral infection. The 8-exon encoded isoform (CAREx8) resides at the apical surface of polarized epithelia, where it is accessible as a receptor for adenovirus entering the airway lumen. Given its pivotal role in viral infection, it is a target for antiviral strategies. To understand the regulation of CAREx8 and determine the feasibility of receptor down regulation, the half-life of total and apical localized CAREx8 was determined and correlated with adenovirus transduction. Total and apical CAREx8 has a relatively short half-life …

Go to article

The Use Of Probiotic Applications In Early Life Stages To Mitigate Batrachochytrium Dendrobatidis Infections In Rana Luteiventris (Columbia Spotted Frogs), Autumn N. Holley Jan 2022

The Use Of Probiotic Applications In Early Life Stages To Mitigate Batrachochytrium Dendrobatidis Infections In Rana Luteiventris (Columbia Spotted Frogs), Autumn N. Holley

2022 Symposium

Chytridiomycosis, an amphibian skin disease caused by a chytrid fungal pathogen, Batrachochytrium dendrobatidis (Bd), has been linked to global amphibian declines. Some amphibian populations are resistant to severe infection due to symbiotic antifungal skin bacteria, but attempts to develop probiotics from these bacteria have been inconsistently successful because bacteria fail to persist on the skin. Studies have largely been conducted on adult and juvenile amphibians, despite amphibians having fewer known mechanisms for microbiome regulation prior to metamorphosis. We hypothesize that probiotics will persist longer and thus be more effective against pathogen infection if they are applied at an early life …

Go to article

Degradation And Nitrogen Cycling In The Context Of Biodiversity-Ecosystem Function Relationships In The Inquiline Bacterial Community Of Darlingtonia Californica, Megan Teigen Jan 2022

Degradation And Nitrogen Cycling In The Context Of Biodiversity-Ecosystem Function Relationships In The Inquiline Bacterial Community Of Darlingtonia Californica, Megan Teigen

Cal Poly Humboldt theses and projects

Biodiversity-ecosystem function (BEF) research aims to explain how species and their environments interact with each other. Microbial communities engage in vital biogeochemical pathways in a variety of natural ecosystems, and yet there are large knowledge gaps about the specific metabolic pathways in which they are involved. Degradation specifically contributes to nitrogen cycling globally through the breakdown of large organic nitrogen compounds into small inorganic nitrogen that is necessary for the survival of many other organisms. In this study, I focused on the degradative function of the inquiline microbial communities found within the carnivorous pitcher plant, Darlingtonia californica. Darlingtonia grows in …

Go to article

Monitoring Photosynthetic Activity Using In Vivo Chlorophyll A Fluorescence In Microalgae And Cyanobacteria Biofilms In The Nerja Cave (Malaga, Spain), Yolanda Del Rosal, Juan Muñoz-Fernández, Paula S.M. Celis-Plá, Mariona Hernández-Mariné, Félix Álvarez-Gómez, Salvador Merino, Félix L. Figueroa Dec 2021

Monitoring Photosynthetic Activity Using In Vivo Chlorophyll A Fluorescence In Microalgae And Cyanobacteria Biofilms In The Nerja Cave (Malaga, Spain), Yolanda Del Rosal, Juan Muñoz-Fernández, Paula S.M. Celis-Plá, Mariona Hernández-Mariné, Félix Álvarez-Gómez, Salvador Merino, Félix L. Figueroa

International Journal of Speleology

The characterization of the most common photosynthetic biofilms in the Nerja Cave by the continuous monitoring of the in vivo chlorophyll a (Chl a) fluorescence and the incorporation of the irradiance as a new environmental variable related to previous studies in the cave, have allowed us to improve our knowledge about the photosynthetic pattern of the biofilms of the cave. Effective quantum yield (ΔF/Fm′) and relative electron transport rate (rETR) were determined during periods of the light, whereas the maximal quantum yield (Fv /Fm) was determined during dark periods. Increases in …

Go to article

Quantification Of Soil Microbial Biomass In The Mcmurdo Dry Valleys, Antarctica, Emily Ruth Reynebeau Nov 2021

Quantification Of Soil Microbial Biomass In The Mcmurdo Dry Valleys, Antarctica, Emily Ruth Reynebeau

Biology ETDs

Quantifying microbial biomass is important for understanding microbial contribution to nutrient cycling and population flux. Widely accepted biomass estimation methods are sufficient for well-studied and high biomass systems, though are often not sensitive enough for systems with extremely low biomass. The McMurdo Dry Valleys of Antarctica are characterized as an extremely harsh environment with severe restrictions on life, with perhaps some of the lowest biomass in the world. We measured prokaryote biomass across Taylor and Wright Valleys using four estimation metrics to determine the most appropriate method for this ecosystem. The chloroform fumigation method was not sensitive enough for the …

Go to article

Comparative Microbiome Analysis Of The Funfus Gardening Ant Species Trachymyrmex Arizonensis, Chase D. Rowan Aug 2021

Comparative Microbiome Analysis Of The Funfus Gardening Ant Species Trachymyrmex Arizonensis, Chase D. Rowan

Biology Theses

Fungus-growing ants (Attini: Formicidae) and their fungal cultivars participate in ant-fungus mutualism that share a 50-million-year-old coevolutionary history. Fungal cultures are grown in gardens alongside ants and a diverse collection of microbes that interact with both species in mutualistic, commensal, and antagonistic relationships. These microbes aid in digestion and detoxification of food, provide essential nutrients, help in nest hygiene, and play a dominant role in defense against pathogens and disease. Microbial communities of many model species have been shown to change in a laboratory setting as compared to their natural environment. High-throughput 16s sequencing of the V4 variable region was …

Go to article

A Stable-Isotope Probing Approach To Modeling Bidirectional Nutrient Exchange In The Microcystis Phycosphere, Malia Gardner Aug 2021

A Stable-Isotope Probing Approach To Modeling Bidirectional Nutrient Exchange In The Microcystis Phycosphere, Malia Gardner

Masters Theses, 2020-current

Cyanobacterial harmful algal blooms (cHABs) plague freshwater systems worldwide and are projected to increase in intensity in the coming decades. cHABs damage aquatic ecosystems by blocking light penetration into the water column, creating hypoxic conditions, and releasing toxins. One of the most prolific cHAB formers is the cosmopolitan genus of cyanobacteria Microcystis. Global climate change and anthropogenic loading of nutrients such as nitrogen (N) and phosphorus (P) fuel Microcystis bloom formation. Increasing global temperatures favor Microcystis because of its high optimal growth temperature. N input is of particular importance for Microcystis because it is unable to fix atmospheric N, …

Go to article

Ecophysiology Of Toxic Bloom-Forming Cyanobacteria And Their Symbionts, Dominique J. Lockwood Aug 2021

Ecophysiology Of Toxic Bloom-Forming Cyanobacteria And Their Symbionts, Dominique J. Lockwood

Masters Theses, 2020-current

Currently, there is a pernicious microbe in the genus Microcystis that is putting the world’s freshwater resources at risk. A member of the phylum Cyanobacteria, otherwise referred to as blue-green algae, Microcystis forms massive algal blooms in lakes and has the potential to produce a toxin, which does not only harm humans, but also pets, livestock, and aquatic life. As recently as 2016, in the city of Toledo, Ohio, nearly 1 million residents went without clean drinking water for an entire weekend due to one of these Microcystis blooms. However, Microcystis does not only bloom in Ohio. In fact, …

Go to article

Lead And Cadmium Detoxification By Halophilic Bacteria Isolated From Solar Salterns In Lebanon, Nadine G. Zmorrod N. G. Zmorrod, Nawal Al Hakawati, Ranya A. Amer, Hoda H. Yusef Jun 2021

Lead And Cadmium Detoxification By Halophilic Bacteria Isolated From Solar Salterns In Lebanon, Nadine G. Zmorrod N. G. Zmorrod, Nawal Al Hakawati, Ranya A. Amer, Hoda H. Yusef

BAU Journal - Science and Technology

Water contamination by heavy metals has gained considerable attention globally. These inorganic pollutants can enter the aquatic environments via different routes thereby threatening biodiversity and human health. Lead and cadmium are hazardous pollutants where their removal by traditional techniques is identified to be costly and ineffective. However, bioremediation by extremophilic microorganisms is considered to be a promising technique as they have considerable potentials to grow in harsh environmental conditions. The present study deals with the isolation of halophilic bacterial isolates from solar salterns in North Lebanon. The isolate H1S9 was identified as Halomonas venusta H9 after showing tolerance to 500 …

Go to article

Analysis Of Symptom Expressions And Transmission Rates Caused By The Plant Pathogen Phytophthora Ramorum On Native Chaparral Plants From The Genus Arctostaphylos, Bharati Gaonker May 2021

Analysis Of Symptom Expressions And Transmission Rates Caused By The Plant Pathogen Phytophthora Ramorum On Native Chaparral Plants From The Genus Arctostaphylos, Bharati Gaonker

Natural Sciences and Mathematics | Biological Sciences Master's Theses

Phytophthora ramorum is the causal agent of Sudden Oak death (SOD), ramorum dieback and ramorum leaf blight which affect both forest environments and nurseries. This oomycete pathogen has had a huge economic impact on the nursery and lumber industry. Forests in California have experienced substantial mortality of oaks affecting the forest dynamics and diversity. Our research investigates four native species and two ornamental cultivars of plants, which belong to the genus Arctostaphylos (manzanita) and are considered to be new hosts for P. ramorum in the chaparral ecosystem of California. Symptom expression and transmission rates were analyzed on Arctostaphylos glauca, …

Go to article

Evidence For Perchlorate-Coupled Molybdenum And Nickel Carbon Monoxide Dehydrogenase Co Oxidation And Characterization Of Novel Perchlorate-Reducing Haloarchaea, Marisa Russell Myers May 2021

Evidence For Perchlorate-Coupled Molybdenum And Nickel Carbon Monoxide Dehydrogenase Co Oxidation And Characterization Of Novel Perchlorate-Reducing Haloarchaea, Marisa Russell Myers

LSU Doctoral Dissertations

Carbon monoxide (CO) has been exploited as a microbial energy source for much of life’s evolutionary history. A phylogenetically diverse array of microorganisms can oxidize CO using two distinct CO dehydrogenases, molybdenum-dependent (Mo-CODH) and nickel-dependent (Ni-CODH). Aerobes and facultative organisms contain Mo-CODHs which allow them to utilize oxygen as an electron acceptor in addition to alternatives such as nitrate and sulfate. Obligate anaerobic organisms contain Ni-CODHs, which oxidize CO at elevated concentrations, but cannot utilize oxygen. In systems where organic matter deposits are limited or absent, atmospheric trace gases such as CO are thought to assist in supporting the growth …

Go to article

Fungi Associated With Herbaceous Plants In Coastal Northern California, Greg Huffman May 2021

Fungi Associated With Herbaceous Plants In Coastal Northern California, Greg Huffman

Natural Sciences and Mathematics | Biological Sciences Master's Theses

The presence of fungal species associated with herbaceous plants was monitored in coastal Marin County, California, USA. The research involved a combination of field sampling surveys and data collection using a stratified random design, pathogen identification through microbiological and molecular analysis, and descriptive analysis and ordination of results. A total of two years of repeated sampling (four times a year) was organized to allow for the detection of seasonal differences in pathogen presence on aerial plant parts. The objective of this study was to identify microbial species present on herbaceous plants using ITS1 sequence analysis. Throughout March of 2018 to …

Go to article

Distribution, Diversity, And Biogeography Of Anaerobic Carbon Monoxide Uptake By Microbial Communities In Soils And Sediments, Amber N. Depoy Mar 2021

Distribution, Diversity, And Biogeography Of Anaerobic Carbon Monoxide Uptake By Microbial Communities In Soils And Sediments, Amber N. Depoy

LSU Master's Theses

Carbon monoxide (CO) is primarily known for being a toxic gas. However, CO is used by microorganisms as an electron or carbon source in a variety of respiratory processes. Different kinds of microorganisms utilize CO aerobically and anaerobically, using two distinct CO dehydrogenases (CODHs). Aerobes oxidize CO using a molybdenum-dependent dehydrogenase (Mo-CODH), while anaerobes utilize a nickel-dependent CO dehydrogenase (Ni-CODH). Studies of the biochemistry and microbiology of aerobic and anaerobic CO oxidation are extensive, but relatively little is known about the ecology of anaerobic CO oxidation. In an effort to test new hypotheses about the ecology of anaerobic CO oxidation, …

Go to article

A Comparison Of Intertidal Metazoan Biodiversity Between Previously Oiled Sheared And Intact Marsh Margins And Between Multiple Salinity Zones In The Coastal Marshes Of Louisiana, Patrick M. Rayle Mar 2021

A Comparison Of Intertidal Metazoan Biodiversity Between Previously Oiled Sheared And Intact Marsh Margins And Between Multiple Salinity Zones In The Coastal Marshes Of Louisiana, Patrick M. Rayle

LSU Master's Theses

Marshes in Louisiana are under threat from numerous natural and anthropogenic sources. A consequence of these threats are sheared marsh margins, which result from the impact of storm surge on previously oiled, weakened marsh. These conditions occurred in Louisiana marshes after Hurricane Isaac in 2012 followed the Deepwater Horizon oil spill in 2010, particularly in the shorelines surrounding Bay Jimmy. The second and third chapters of this thesis focus on the differences in biodiversity between the sheared and intact marsh margins in impacted sites in Bay Jimmy. Metabarcoding methods were used to determine community composition of the sediment within marsh …

Go to article

Inhibition Of Biofilm Formation By The Synergistic Action Of Egcg-S And Antibiotics, Shrameeta Shinde, Lee Lee, Tinchun Chu Jan 2021

Inhibition Of Biofilm Formation By The Synergistic Action Of Egcg-S And Antibiotics, Shrameeta Shinde, Lee Lee, Tinchun Chu

Department of Biology Faculty Scholarship and Creative Works

Biofilm, a stress-induced physiological state, is an established means of antimicrobial tolerance. A perpetual increase in multidrug resistant (MDR) infections associated with high mortality and morbidity have been observed in healthcare settings. Multiple studies have indicated that the use of natural products can prevent bacterial growth. Recent studies in the field have identified that epigallocatechin gallate (EGCG), a green tea polyphenol, could disrupt bacterial biofilms. A modified lipid-soluble EGCG, epigallocatechin-3-gallate-stearate (EGCG-S), has enhanced the beneficial properties of green tea. This study focuses on utilizing EGCG-S as a novel synergistic agent with antibiotics to prevent or control biofilm. Different formulations of …

Go to article

The Effect Of An Acidified-Gypsum Mixture On Broiler Litter Urease-Producing Bacteria And Nitrogen Mineralization, Taylor Chapman, Christopher D. Burt, Dave Bachoon, Miguel L. Cabrera, Christopher Horacek Jan 2021

The Effect Of An Acidified-Gypsum Mixture On Broiler Litter Urease-Producing Bacteria And Nitrogen Mineralization, Taylor Chapman, Christopher D. Burt, Dave Bachoon, Miguel L. Cabrera, Christopher Horacek

Graduate Research Showcase

Broiler chicken (Gallus gallus domesticus) production is one of the largest agricultural sectors in the state of Georgia. Broiler litter produced by broiler facilities is rich in organic nitrogen (N), specifically urea, which can be mineralized by poultry litter urease-producing bacteria (PLUP) forming ammoniacal-N (NH3/NH4+). A large portion of NH3/NH4+ can be lost as ammonia (NH3) gas, which negatively impacts bird health and profitability. The release of NH3 from litter is strongly influenced by the pH of the litter. Flue-gas desulfurization gypsum (FGDG) has been suggested …

Go to article

First Prev Next Last