Environmental Microbiology and Microbial Ecology Commons^™

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 …

Microbiological Study In A Gneissic Cave From Sri Lanka, With Special Focus On Potential Antimicrobial Activities, Ethige Isuru P. Silva, Pathmakumara Jayasingha, Saman Senanayake, Anura Dandeniya, Dona Helani Munasinghe

International Journal of Speleology

The emergence of antibiotic resistance is a global health crisis, thus the search for novel antimicrobial compounds has become a continuous necessity. Underexplored and extreme environments, such as cave ecosystems, have been identified as a promising potential source for the discovery of novel microorganisms with novel antimicrobial compounds (AMC). This study presents the first cave microbiological investigation in Sri Lanka, with a special preference for bioprospecting of novel AMC. The cave sediment characterization demonstrated the presence of close to strong acidic conditions (pH 3.1 – 3.3) and thus indicates the possibility of isolating acidophilic microorganisms. Eight cave wall/ceiling fungal strains …

The Response Of Marine Synechococcus To A Landscape Of Environmental Stressors: A Proteomic Exploration, Dana E. Michels

Master's Theses

In the field of marine microbial ecology, many questions remain unanswered with regards to the physiological trade-offs made by phytoplankton to maximize growth (e.g., nutrient acquisition) and minimize loss (e.g., predation defenses). These tradeoffs, which occur at the cellular level, have wide reaching impacts on food web dynamics and global biogeochemical cycles. In the first chapter, we explored the use of a non-canonical amino acid (NCAA) technique, bioorthogonal non-canonical amino-acid tagging (BONCAT), in phytoplankton model systems. This technique has potential to work well in natural systems by enabling isolation of only newly synthesized proteins during an incubation period with the …

Japanese Quail (Coturnix Japonica) As A Novel Model To Study The Relationship Between The Avian Microbiome And Microbial Endocrinology-Based Host-Microbe Interactions, James Keane, Joshua M. Lyte, Julia Eckenberger, Nicholas Anthony, Sandip Shrestha, Daya Marasini, Karrie M. Daniels, Valentina Caputi, Annie M. Donoghue, Mark Lyte

Articles

Background

Microbial endocrinology, which is the study of neuroendocrine-based interkingdom signaling, provides a causal mechanistic framework for understanding the bi-directional crosstalk between the host and microbiome, especially as regards the effect of stress on health and disease. The importance of the cecal microbiome in avian health is well-recognized, yet little is understood regarding the mechanisms underpinning the avian host-microbiome relationship. Neuroendocrine plasticity of avian tissues that are focal points of host-microbiome interaction, such as the gut and lung, has likewise received limited attention. Avian in vivo models that enable the study of the neuroendocrine dynamic between host and microbiome are …

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 …

Metabolomics-Based Analysis Of Miniature Flask Contents Identifies Tobacco Mixture Use Among The Ancient Maya, Mario Zimmermann, Korey J. Brownstein, Luis Pantoja Díaz, Iliana Ancona Aragón, Scott R. Hutson, Barry Kidder, Shannon Tushingham, David R. Gang

Anthropology Faculty Publications

A particular type of miniature ceramic vessel locally known as “veneneras” is occasionally found during archaeological excavations in the Maya Area. To date, only one study of a collection of such containers successfully identified organic residues through coupled chromatography–mass spectrometry methods. That study identified traces of nicotine likely associated with tobacco. Here we present a more complete picture by analyzing a suite of possible complementary ingredients in tobacco mixtures across a collection of 14 miniature vessels. The collection includes four different vessel forms and allows for the comparison of specimens which had previously formed part of museum exhibitions with recently …

Pressure Effects On Sulfur‐Oxidizing Activity Of Thiobacillus Thioparus, Jorge R. Osman, Hervé Cardon, Gilles Montagnac, Aude Picard, Isabelle Daniel

Life Sciences Faculty Research

Carbon capture and storage technologies are crucial for reducing carbon emission from power plants as a response to global climate change. The CarbFix project (Iceland) aims at examining the geochemical response of injected CO2 into subsurface reservoirs. The potential role of the subsurface biosphere has been little investigated up to now. Here, we used Thiobacillus thioparus that became abundant at the CarbFix1 pilot site after injection of CO2 and purified geothermal gases in basaltic aquifer at 400–800 m depth (4–8 MPa). The capacity of T. thioparus to produce sulfate, through oxidation of thiosulfate, was measured by Raman spectroscopy as a …

Complete Genome Sequence Of Strain Ss-5, A Magnetotactic Gammaproteobacterium Isolated From The Salton Sea, A Shallow, Saline, Endorheic Rift Lake Located On The San Andreas Fault In California, Denis Trubitsyn, Caroline L. Monteil, Corey Geurink, Viviana Morillo Lopez, Luiz Gonzaga Paula De Almeida, Ana Tereza Ribeiro De Vasconcelos, Fernanda Abreu, Dennis A. Bazylinski, Christopher T. Lefevre

Life Sciences Faculty Research

© 2021 American Society for Microbiology. All rights reserved. We report the 3.7-Mb genome sequence of strain SS-5, a magnetotactic, sulfur-oxidizing rod and member of the family Chromatiaceae of the class Gammaproteobacteria, which biomineralizes membrane-bound, elongated, prismatic octahedral, magnetite nanocrystals. This genome sequence brings further diversity for understanding the origin and evolution of magnetotaxis and magnetosome biomineralization.

Assessment Of Bacterial Community Structure And Characterisation Of Novel Bacterial Species In Weaver Ants Oecophylla Smaragdina, Chua Kah Ooi

Student Works (2020-2029)

The Asian weaver ant, Oecophylla smaragdina has major workers that exhibit strong territorial behaviour and are aggressive predator of other arthropods. This makes them an effective biocontrol agent against many agricultural-important insect pests. Despite its importance in pest management, microbiome information of O. smaragdina is limited. In this study, the bacterial microbiome of O. smaragdina was characterized using 16S rRNA gene amplicon sequencing. Across all 12 samples, 97.8% of the sequences constituted 16 major operational taxonomic units (OTUs) that were assigned to eight bacterial families. The core bacterial microbiome was dominated by families Acetobacteraceae and Lactobacillaceae. Spatial variation attributed to …

Utilizing Plastic-Degrading Microbes For Plastic Degradation, Brandon Garcia

Global Sustainable Development Projects

Our oceans are full of pollution and a large portion of those are plastics. They resist degradation from the elements and have long half-lives. About 300 million metric tons of plastic are dumped into our oceans every year. Many of these include polyethylene (PE), polypropylene (PP), polystyrene (PS), etc. Much of this is not recycled and so there is a massive accumulation of it present in our oceans. Microbes tend to form biofilms on these plastics and break them down. However, the relationship between plastics and the diversity of biofilm communities are being understood as well as how we can …

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 …

Monitoring Lake Sinclair, Margaret Blackledge

Graduate Research Showcase

Algae, a polyphyletic group of aquatic primary producers, play a great part in earth’s biosphere. They produce half of the world’s oxygen and are major contributors to aquatic biodiversity. When conditions are favorable to a species, algae will bloom. Some algal species will produce algal toxins during a bloom as a potential mechanism to concentrate carbon. Due to the integral part they play in aquatic food webs, nutrient cycling and the potential for harmful algal blooms, algal communities are monitored to determine the health and safety of aquatic environments. Lake Sinclair in middle Georgia is a good model where in …

Choices On Sampling, Sequencing, And Analyzing Dna Influence The Estimation Of Community Composition Of Plant Fungal Symbionts, Jonathan A. Cale, Natalie Scott, Gregory J. Pec, Simon M. Landhäusser, Justine Karst

Publications: Biology

Plant root symbionts, namely mycorrhizal fungi, can be characterized using a variety of methods, but most of these rely on DNA. While Sanger sequencing still fulfills particular research objectives, next‐generation sequencing currently dominates the f ield, thus understanding how the two methods differ is important for identifying both opportunities and limitations to characterizing fungal communities. In addition to testing sequencing methods, we also examined how roots and soils may yield different fungal communities and how disturbance may affect those differences. We sequenced DNA from ectomycorrhizal fungi colonizing roots of Pinus banksiana and found that operational taxonomic unit richness was higher, …

Characterization Of Microbial Populations In Landfill Leachate, Umut M. Bicim, Hanna Fulford, Lori A. Hoagland, Alejandro R. Sanchez, Amisha D. Shah, Inez Hua

Discovery Undergraduate Interdisciplinary Research Internship

In the United States, municipal solid waste (MSW) landfills remain a potential mining source of recoverable materials, including but not limited to critical, precious, and rare earth metals found in electronic waste. This is possible due to collectible leachate that filters through MSW landfills, carrying metals, nutrients of value, and microbes—some of which may hold key metal bioleaching properties—within. The purpose of this study is to begin analyzing leachate from MSW landfills in the American Midwest to understand the composition of microbial communities within these landfills. Landfill leachate samples sourced in northern Indiana, representing the landfill process during unique times …

Characterization Of The Rumen Bacterial Communities Of Bison Heifers Fed A Grass-Based Diet Vs A Grain-Based Free-Choice Diet, Anlly Miley Fresno Rueda

Electronic Theses and Dissertations

A century ago, the North American grasslands and prairie ecosystems were dominated by bison. At least 30 million bison roamed the Great Plains when the first explorers arrived. By 1900, there were little over a thousand bison remained in the United States and Canada. Recovery efforts has been made since the 20th century to reestablish the herds and increase the bison population. Today, over 500,000 bison are distributed across North America, with more than 90% of the existing bison population under commercial production. Modern conservation strategies are made via the collaborative efforts of conservationist, producers, and researchers, resulting in increased …

Impact Of Arbuscular Mycorrhizal Fungi On Conyza Canadensis Drought Responses And Possible Mechanisms, Kian G.M. Speck, Ylva Lekberg, Anna Sala

Undergraduate Theses, Professional Papers, and Capstone Artifacts

• Arbuscular mycorrhizal fungi (AMF) are important plant mutualists that can facilitate plant responses to various environmental stressors, such as drought. A plant that may benefit from AMF-induced drought tolerance is Conyza canadensis due to its ability to thrive in dry conditions and its high colonization rate. However, no studies have researched C. canadensis in this context and the exact mechanisms of AMF-induced drought tolerance are still unknown.
• To better understand if and how AMF facilitate drought response in C. canadensis, we conducted a greenhouse experiment comparing the response of mycorrhizal and non-mycorrhizal plants to three watering levels. We measured …

Comparison Of The Effects Of Land Use / Land Cover On Water Quality And The Intertidal Marine Macroalgae Communities At The Fluvial Outflows Of The Dingle Peninsula, Cassandra Lew

Theses

The Milltown, Feohanagh, and Owenmore river basins located on the Dingle Peninsula in Ireland were studied to see how variation in land use and land cover (LU/LC) affected water quality and the macroalgal communities at each river’s respective fluvial outflow. Abundance and composition of macroalgae in river and coastal water bodies have been designated as an indicator of water quality according to the Water Framework Directive 2000. The results of this study found that the Feohanagh’s macroalgal community had the highest species richness for most months while the Milltown had the highest Shannon Diversity Index. The Owenmore’s community was consistently …

Roles Of Non-Frankia Bacteria In Root Nodule Formation And Function In Alnus Sp., Kelsey Christine Mercurio

Honors Theses and Capstones

Plant roots are home to a wide variety of beneficial microbes; understanding and optimizing plant-microbe interactions may be critical to enhance global food security in a sustainable, equitable way. With the help of their nitrogen-fixing bacterial partner, Frankia, actinorhizal plants form symbiotic root nodules and play important roles in agroforestry and land reclamation. However, Frankia does not live alone in nodules, and the other microbial residents may contribute to nodule formation and function. We collected root nodules from alder trees (Alnus sp.) in 2018 and 2019, then isolated DNA and individual bacterial strains to characterize the nodule microbial …

Effects Of Biofertilizer On Soil Nutrient Cycling And The Productivity Of Bioproduct Crops In Marginal Soils, Kieran B. Liseski

Graduate Theses, Dissertations, and Problem Reports (ETD)

Recently there has been increased interest in the use of marginal lands in order to grow bioproduct crops. Utilizing marginal lands to grow bioproduct crops such as Miscanthus x giganteus and Panicum virgatum could not only improve soil quality and minimize negative environmental impacts on the surrounding ecosystems but could also offer economic benefits to growers in rural areas. Because marginal soils tend to reduce crop yields compared to prime farmlands even when growing bioproduct crops, which tend to be more robust than traditional food crops, augmenting the soil with biofertilizers (i.e., the direct addition of viable microbial cells) could …

Comparing Capabilities Of Shewanella Oneidensis Mr-1 And The Microbial Community Of Iron Caves To Reduce Fe(Iii), Aaron Douglas Pham

Williams Honors College, Honors Research Projects

Caves are generally formed by the erosion and/or dissolution of rock and its subsequent removal by water. Iron ore caves (IOCs) form despite being hosted by relatively insoluble and weathering-resistant rock. Due to the discovery of a microbial community behind the walls of these caves, it was hypothesized that these bacteria could be responsible for speleogenesis. Iron ore exists in an oxidized (Fe(III)) state, but reduced (Fe(II)) form is soluble. It was further reasoned that the bacteria might be able to reduce Fe(III) through direct metabolic activity, which uses iron as an electron acceptor. Here we show that cave microorganisms …