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Analysis Of Soxs In S. Typhimurium By Transposon Mutagenesis, Joel Hanns, Brenda Pratte, Lon Chubiz PhD, Lauren Daugherty 2022 University of Missouri-St. Louis

Analysis Of Soxs In S. Typhimurium By Transposon Mutagenesis, Joel Hanns, Brenda Pratte, Lon Chubiz Phd, Lauren Daugherty

Undergraduate Research Symposium

The mar-sox-rob regulon has been implicated in transcriptional regulation of several stress responses, such efflux of antibiotics, enzymes that break down reactive oxygen species, repression of biofilm formation, or repression of motility through downregulation of flagellar expression. This system is conserved among enteric bacteria and has been studied in species, such as E. coli and S. typhimurium. Some of these mechanisms can be costly and slow cell growth while increasing the probability of survival through tolerance of toxic environments. SoxS works in coordination with SoxR to respond to redox stress encountered by the cell. Interestingly, the overexpression of SoxS in ...


Biomass Estimation Of Marine Biofilms On Plastic Surfaces, Kian Banihashemi, Fernando Javier Gil 2022 California Polytechnic State University, San Luis Obispo

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 ...


Parameter Estimation Using Nudging On The Logistic Growth Equation, Susan Rogowski 2022 Florida State University

Parameter Estimation Using Nudging On The Logistic Growth Equation, Susan Rogowski

Biology and Medicine Through Mathematics Conference

No abstract provided.


Antibiotic-Resistant Bacteria In Freshwater Crayfish, Colby Finch 2022 University of Mississippi

Antibiotic-Resistant Bacteria In Freshwater Crayfish, Colby Finch

Honors Theses

The presence of antibiotic-resistant bacteria is increasing in natural aquatic environments. Alongside this, organisms that live in these ecosystems are increasingly harboring antibiotic-resistant bacteria. In this study, I analyzed the capacity for the crayfish species Procambarus vioscai paynei to harbor antibiotic-resistant bacteria. Crayfish, as well as water and sediment, were sampled from a pond at the University of Mississippi Field Station. The guts of crayfish were plated on TSA agar, as well as agar containing vancomycin, erythromycin, penicillin, tetracycline, or ciprofloxacin. Following incubation, counts of bacteria were determined. Selected bacterial isolates were tested for multiple antibiotic-resistance. Bacterial isolates were also ...


Effect Of Mycorrhizae Inoculation On The Growth And Success Of Three Taxodium Distichum Hybrids In Saline - Impacted Coastal Soils, Elif ilhan 2022 Stephen F. Austin State University

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 each ...


Comparative Transcriptomic Study Between Cyanobacteria That Contain Chlorophyll D And Those That Lack Chlorophyll D, Fernanda Montoya 2022 Northern Illinois University

Comparative Transcriptomic Study Between Cyanobacteria That Contain Chlorophyll D And Those That Lack Chlorophyll D, Fernanda Montoya

Honors Capstones

All cyanobacteria, which perform oxygenic photosynthesis on Earth, contain the photosynthetic pigment chlorophyll a (Chl a) that absorbs light in the violet and red region of the visible spectrum. Cyanobacteria of the Acaryochloris species, however, contain the rare photosynthetic pigment chlorophyll d (Chl d) that absorbs light in the far-red region. Chl d’s ability to absorb light in this region allows it to avoid competing with other photosynthetic organisms for light. Creating a photosystem that uses Chl d in plants would be of great use for agricultural land optimization, but requires knowledge of the biosynthetic pathways of Chl d ...


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 2022 University of Rhode Island

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 in 2016 ...


Describing The Effect Of Thin Layer Sediment Placement On Coastal Microbial Communities Using Foraminifera Diversity, Elizabeth B. Billings 2022 University of Rhode Island

Describing The Effect Of Thin Layer Sediment Placement On Coastal Microbial Communities Using Foraminifera Diversity, Elizabeth B. Billings

Senior Honors Projects

Salt marshes are rich ecosystems that play an important role in aquatic food systems and prevent erosion while also providing essential habitats for wildlife. Climate change has resulted in rising sea levels and erosion of these coastal wetlands. Thin Layer Sediment Placement (TLP) is a restoration effort being implemented to mitigate the effects of climate change on coastal ecosystems. The TLP process raises elevation of the marsh and provides substrates for vegetative growth by spraying dredged sediment over existing marsh. The impacts of TLP on microbial populations is not widely understood, therefore metrics are required to study the effects of ...


Making Sense Of Soil Microbiome Complexity For Plant And Ecosystem Function In A Changing World, Kendall K. Beals 2022 University of Tennessee, Knoxville

Making Sense Of Soil Microbiome Complexity For Plant And Ecosystem Function In A Changing World, Kendall K. Beals

Doctoral Dissertations

Soils contain the highest biodiversity on Earth. While the importance of the soil microbiome for larger-scale ecological phenomena such as nutrient and carbon cycling, plant growth and plant community dynamics is well-established, the fundamental question of the ecological and evolutionary function of this immense belowground microbial diversity for plant and ecosystem function still remains a great challenge in microbial ecology research. The objective of this dissertation is to understand how the importance of soil microbial community composition for plant and ecosystem function and how changes to soil microbial community composition from climate change-induced disturbance events, specifically fire, influence plant and ...


The Spatial, Temporal, And Ecological Constraints Of Plant-Host Associated Microbial Communities, Jonathan Dickey 2022 University of Tennessee, Knoxville

The Spatial, Temporal, And Ecological Constraints Of Plant-Host Associated Microbial Communities, Jonathan Dickey

Doctoral Dissertations

With the development of next generation sequencing technology, ecologists have recently been able to describe microbial communities across a wide array of niches at an accelerated pace. De-novo-based patterns in richness and relative abundance have been described for bacterial and fungal communities in terrestrial, aquatic, and host-associated microhabitats. A recent synthesis has shown that these communities exhibit similar geographical patterns that have been traditionally described for plant and animals. Yet, there is a lack of hypothesis-based research for host-associated microbial communities. Throughout this dissertation, I will address how spatial scale, sequencing resolution, and manipulative rainfall exclusion govern host-associated microbial communities ...


Ecological Controls On Successional Patterns In Bloom-Forming Cyanobacteria, Kyla L. Hooker 2022 University of Tennessee, Knoxville

Ecological Controls On Successional Patterns In Bloom-Forming Cyanobacteria, Kyla L. Hooker

Masters Theses

Harmful algal blooms are widespread in lake ecosystems but the ecological factors underlying their formation and maintenance are poorly understood. We revisit classical ecological theories which characterize and evaluate contrasting bottom-up and top-down influences on the selection of phytoplankton groups, such as Microcystis aeruginosa. We begin with a data compilation and analysis of environmental data from Lake Erie. This data analysis of nutrient concentrations, pigment concentrations, and zooplankton biomasses helps us understand and interpret what is happening in the environment throughout the year. Thus, allowing us to build a mathematical model to test our hypothesis. Our mathematical model asses a ...


Diversity Of Bacteriophage In Burkholderia Species, Abigail Price 2022 Bowling Green State University

Diversity Of Bacteriophage In Burkholderia Species, Abigail Price

Honors Projects

Bacteriophages are viruses that infect and replicate within bacteria and offer the potential of a therapeutic alternative to chronic infections that do not respond to antibiotic-based therapies. B. vietnamiensis is one of a number of Burkholderia species involved with chronic drug resistant infections in the lungs of individuals with compromised respiratory systems, as found in those with chronic obstructive pulmonary disease and, most especially, are of particular significance in patients with cystic fibrosis. The diversity of the Burkholderia species is explored by using online databases and looking at bacteriophage or phage-encoding viruses found in B. vietnamiensis. The open reading frames ...


Assessing Environmental Factors That Influence Cyanobacterial Blooms In Skinn Lake, Kloe Atwood 2022 Bowling Green State University

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 ...


Composting During Winter Versus Summer: A Microbial Analysis, Madison Ochs 2022 Western Michigan University

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 ...


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

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 ...


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

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 ...


Analysis Of Edna To Assess Effects Of Water Quality On Freshwater Fungal Diversity In A Virginia Coastal Watershed, Lauren French 2022 William & Mary

Analysis Of Edna To Assess Effects Of Water Quality On Freshwater Fungal Diversity In A Virginia Coastal Watershed, Lauren French

Undergraduate Honors Theses

Freshwater fungi comprise a phylogenetically and functionally diverse group which contributes to wide-ranging ecosystem processes in aquatic systems. Saprotrophic fungi convert detritus into nutrient-rich food sources for fish and invertebrates, whereas pathogenic and parasitic fungi can cause disease and population declines of other aquatic organisms. With their diverse and important roles, changes in freshwater fungal community structure may have far-reaching impacts on ecosystems. To understand how natural and anthropogenic stressors to freshwater systems impact fungal-mediated ecosystem processes, a greater understanding of the taxonomic and functional composition of freshwater fungal communities is needed. We assessed relationships among freshwater habitat types, water ...


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

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 lack of ...


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 2022 Department of Biological Sciences, Igbinedion University, Okada, Edo State, Nigeria

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 ...


Tiny Earth, Tinier Microbes: An Experiential Learning Approach To Antibiotic Discovery, Emily Kassing 2022 University of Nebraska - Lincoln

Tiny Earth, Tinier Microbes: An Experiential Learning Approach To Antibiotic Discovery, Emily Kassing

Honors Theses, University of Nebraska-Lincoln

Antimicrobial resistance is one of the greatest global health challenges of the 21st century as antibiotic discovery has slowed even as scientific knowledge about AMR has progressed. At the same time, science education has turned to active learning approaches like CUREs, or course-based undergraduate research experiences, to achieve educational objectives while engaging students in real-life research. The Tiny Earth Project is a global research initiative that seeks to crowdsource antibiotic discovery by recruiting undergraduate students to screen soil samples for antibiotic producers. The goal of this study was to determine the viability of translating the Tiny Earth programming to ...


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