Integrative Biology Commons^™

A Spatial And Multivariate Approach To Examining Effects Of Urbanization On Nitrogen Sources, Organic Matter Inputs, And Trophic Structure In Streams Of Cobb And Paulding Counties, Georgia., Katharine Horning

Master of Science in Integrative Biology Theses

Urbanization and land use changes have a negative effect on streams often causing numerous physical changes in stream morphology, a change in nutrient concentrations, and altered ecosystems contributing to a loss of habitat, decreased biodiversity, and loss of stability for ecosystem function (Walsh et al., 2005; Meyer et al., 2005; Cardinale and Palmer, 2012). The use of stable isotope analysis for monitoring could be valuable because it accounts for temporal integration from anthropogenic wastewater inputs, characterized by a shift in the abundance of ¹⁵N. This project had three main objectives: (1) to examine how nitrogen and carbon sources are …

Chemically Induced Phytoextraction Of Lead (Pb) Contaminated Soil By Switchgrass (Panicum Virgatum L.), Austin Gilly

Master of Science in Integrative Biology Theses

Soils contaminated with lead (Pb) from human activities including industrial byproducts create an environmental and human health risk. Phytoextraction through chemical acquisition of Pb in soils offer a potentially cost effective and ecologically driven approach to remediation. Switchgrass (Panicum virgatum L.) is known to have a tolerance for a wide range of heavy metals including Pb. Switchgrass is also able to grow in a wide range of climates. Soil chemistry manipulation, using chelates and plant growth promoters could provide an effective field method for phytoremediation using switchgrass. In this study chemically enhanced phytoextraction using the soil-fungicide Infuse (active ingredient …

Drosophila Model To Study Muscle Atrophy, Aaron Aghai

Master of Science in Integrative Biology Theses

Muscle atrophy (MA) is a phenomenon of muscle mass loss due to accelerated protein degradation in muscle fibers. Some pathological conditions, such as chronic inflammation or cancer, induce accelerated MA, which complicates medical treatment, hampers recovery of fragile patients, and ultimately can be the cause of a patient’s death. To gain better control over MA, more information is required about the whole spectrum of genetic factors that can influence MA.

Drosophila provides an excellent platform for genetic screening, although it has somewhat limited utility for MA research since insect muscles lack the level of plasticity found in mammalian muscles. We …

Cbd & Ethanol Disrupt Early Embryonic Development, Janasha Goffigan-Holmes

Master of Science in Integrative Biology Theses

The heavily conserved neural circuits that govern the vertebrate reward system, receive sensory stimuli and produce appropriate, self-preserving responses that correspond to experience-based learning and are driven by the communication of dopamine. Many of these circuits lie within the endocannabinoid system (ECS). At the most basic level, the ECS drives homeostatic behaviors, such as seeking nutrients, avoiding danger, and reproductive function. Unfortunately, this system can be hijacked by psychoactive drugs which ultimately alter the expression of dopamine. Cannabis sativa has two main active ingredients, THC and CBD, which modify the ECS receptor’s ability to bind to hormones and neurotransmitters such …

Evaluating Regional Agricultural Wastes As Substrates For The Mycelial Growth And Fruiting Body Yield Of Pleurotus Ostreatus, Daniel Rhiner

Master of Science in Integrative Biology Theses

Pleurotus ostreatus, commonly known as the oyster mushroom, is a widely cultivated culinary mushroom known for its ability to colonize a variety of lignocellulosic agricultural wastes. The ability of P. ostreatus to utilize these types of wastes as growth substrates suggests a potential for this organism to convert agricultural waste streams into locally productive and regenerative systems. Agriculture is a leading contributor to Georgia’s economy, but it also produces large amounts of plant-based agricultural wastes of little to no value. Repurposing these wastes into profitable culinary and medicinal mushrooms has become an increasingly appealing approach to mitigating these wastes. …

Comparative Whole-Genome And Phenotype Analyses Of Virulence Factors And Lethality In Nematode Challenge Assay Among Aeromonas Isolates, Pyeongsug Kim

Master of Science in Integrative Biology Theses

Aeromonads are bacteria found globally in fresh and brackish waters, with some species causing water-borne diseases vertebrate hosts such as diarrhea and wound-infections in humans and motile Aeromonas septicemia in fish. Although many virulence factors have been described, determining which factors are most important in pathogenesis is ongoing. To examine this further, the genomes of five Aeromonas strains isolated from various animals were sequenced and annotated in this study. Each isolate was further characterized using comparative genomic analyses and testing for production of selected virulence factors. Although previously identified as Aeromonas hydrophila, modern genotypic approaches including multilocus sequence typing …

The Historic Fire Return Interval And The Ecological Effects Of Fire Suppression On Montane Longleaf Pine Dominated Ecosystems In Northwestern Georgia., Christopher Waters

Master of Science in Integrative Biology Theses

Longleaf pine ecosystems have experienced pronounced declines across the southeastern United States since Euro-American settlement took place in the late 19th century. These declines were primarily caused by federal fire suppression policies implemented in the 1920’s, in combination with resource harvesting and land use conversion. In an absence of fire, tree species composition of frequently burned xeric ecosystems progressively becomes more mesic and fire-intolerant (i.e. mesophication). The change in the species composition and historic fire frequency of a montane longleaf pine ecosystem located in Sheffield Wildlife Management Area (WMA), Paulding County, Georgia was investigated. The change in forest composition …

High-Resolution Mapping Of Fish Conservation Priorities Within The Mobile River Basin, James R. Carl

Master of Science in Integrative Biology Theses

Identifying potential protected areas is increasingly important as freshwater fishes and associated aquatic organisms are under increasing peril. Human population, growth and subsequent landscape alteration, is degrading water quality and changing the physical characteristics of streams, potentially threatening aquatic species. The goal is to assess the capacity for protected areas to maintain diverse stream fish communities within the Mobile River Basin, including the upper Coosa River basin, by overlaying projections of fish species distributions and footprints of protected areas. Tools for identifying fish species distributions, environmental predictors, and potential protected areas include spatial conservation prioritization algorithms combined with open access …

Isolation And Characterization Of Bacteriophages Infecting Enterobacter Cloacae To Reduce Bloater Defect In Cucumber Fermentations, Samantha Thompson

Master of Science in Integrative Biology Theses

Fermented cucumbers are one of the most important fermented vegetables consumed worldwide. During cucumber fermentations, certain undesirable changes may occur. One of such changes is known as bloater defect (hollow cavities in fermented cucumbers), which is primarily caused by gas-producing bacteria including Enterobacter cloacae. Bloater defect lowers product quality and leads to significant economic loss to the pickle industry, and effective preventative methods are needed. Bacteriophages (phages) are highly host-specific bacteria killers. Use of phages to control unwanted bacteria in foods is a promising approach because phages do not change food properties. The goals of this research were to …

Utilization Of The Cell Penetrating Peptide Tat-Cam In New Biological Systems: Fungal And Bacterial Cell Lines, Krista Barbour

Master of Science in Integrative Biology Theses

Cell penetrating peptides (CPPs) are biomolecular vehicles or systems that mediate the delivery of proteins into different cell lines. Since their discovery in the late 1980s, the CPP delivery system has primarily been explored in different types of mammalian cells. The technology has demonstrated promise in providing itself as an alternative delivery mechanism to transport biomolecules into different mammalian cell lines. CPPs have previously been shown to penetrate the cell membranes of fungi and bacteria, however, CPP mediated delivery of other proteins and biomolecules into these two microorganisms have yet to be explored. In this thesis project, this phenomenon is …

Differential Analysis Of Individual Centruroides Vittatus Venom

Symposium of Student Scholars

Scorpions are well known, venomous arthropods (Class: Arachnida, Order: Scorpiones). Their venom is composed of neurotoxins, proteases and cytotoxic peptides which plays a major role in toxic components such as inflammatory, antimicrobial and hemolytic activity. Venom is key for the survival of scorpions as it is involved in defense against prey and in feeding on predators. Centruroides vittatus (bark scorpion) is commonly found in North America, with habitat ranges from Nebraska to southern Texas. For this study, scorpions were harvested from Laredo, Texas (27˚57’ N, 99˚43’ W), held in captivity for 4 months and fed a consistent diet of Acheta …

Ecology Of Upland Snake Communities In Managed Montane Longleaf Pine Habitats Of Georgia, Miranda Gulsby

Master of Science in Integrative Biology Theses

Longleaf pine ecosystem decline in the Southeast United States has led to intensive land management implementation with the goal to benefit both the ecosystem and at-risk species. Addressing at-risk snake populations in these longleaf pine ecosystems, for instance, requires understanding both community and species level ecology of snakes in these managed forests. Data for snakes in the montane (mountain) longleaf pine habitats remains unclear since management practice implementation. Currently, intensive restoration of montane longleaf pine habitats is taking place within two Wildlife Management Areas (WMA) in the Raccoon Creek Watershed of Northwest Georgia, Sheffield and Paulding Forest. These areas differ …

Assessment Of Culverts And Bridges As Roosting Habitat For Perimyotis Subflavus (Tri-Colored Bat) And Disease Transmission Corridors For Pseudogymnoascus Destructans, Kelly Lutsch

Master of Science in Integrative Biology Theses

Pseudogymnoascus destructans is an emerging fungal pathogen causing precipitous declines in North American bats due to the development of white-nose syndrome. Since 2006, 34 U.S. states and 7 Canadian provinces have confirmed the presence of P. destructans. Due to the rapid spread of P. destructans across the eastern United States, habitat characterization and disease monitoring has become vital to conserving remnant populations. Bats have been observed in multiple states using non-traditional habitat, such as interstate culverts, for roosting. To investigate their use of anthropogenic structures in coastal Georgia, an area where P. destructans has yet-to-be detected, comprehensive bridge and …

Using Instream Stationary Antennas To Monitor The Movements Of Warm Water Fishes In A Reach Of Stream Bisected By A Culvert, William Commins

Master of Science in Integrative Biology Theses

In this study I investigated the differences in the non-migratory movement patterns of six fish species in a 280m reach of stream bisected by a culvert (impeded), and a 300m reach of stream with no movement barriers (unimpeded). This study took place between July 1, 2018 and November 14, 2018 in Raccoon Creek, Paulding County, Georgia. I used 12mm passive integrated transponder tags and four instream stationary antennas to monitor the movements 429 fishes. The antennas redetected 262 of the 429 individuals (61.1%), and 48% of fishes were redetected more than 10 times. The proportion of tagged individuals detected by …

Unraveling The Neurogenin/Ngn-1 Gene Regulatory Network Of C. Elegans Using Classical Genetics And Comparative Transcriptomics, Elyse Christensen

Master of Science in Integrative Biology Theses

Proper nervous system development is required for an organism’s survival and function. Defects in neurogenesis have been linked to neurodevelopmental disorders such as schizophrenia and autism spectrum disorders. Understanding the gene regulatory networks that orchestrate neural development, specifically cascades of proneural transcription factors, can better elucidate which genes are most essential in governing early neurogenesis. Neurogenins are a family of such factors that are both sufficient and necessary for the development of neural sub-types in mice, primarily through the regulation of other factors, particularly NeuroD. The objective of this study was to evaluate previously established regulatory targets of neurogenin(ngn-1 …

Neural Development To Neurodegeneration Through The Mind Of A Worm, Miranda Arnold

Master of Science in Integrative Biology Theses

Defects in the nervous system can impact the normal function of an organism. By examining mutations during neuronal development, we can better understand the significance of specific pathways. The EphR/ephrin pathway is crucial for axonal guidance during development. The simple organism, C. elegans, allow us to study the impact of EphR/ephrin genes on neuronal morphology, synapse connections, and basic behavior. In specific EphR/ephrin mutants, we see change in morphology and loss of synapses in a thermosensory and also a chemosensory circuit. These mutations can also lead to defects in food searching behaviors. These observations lead us to conclude that …

The Developmental And Behavioral Effects Of Δ9-Tetrahydrocannabinol On A Spastic Mutant, Victoria Mendiola

Master of Science in Integrative Biology Theses

Hyperekplexia is a neurological disorder affecting infants and can be characterized by excessive startle reactions in response to unexpected stimuli. This disease can be modeled in zebrafish in the bandoneon (beo) mutant, where the glrbbmutation results in glycine receptor (GLYR) loss of function glycine receptors and ultimately, improper inhibitory signaling. Though hyperekplexia is a glycinergic-based signaling disorder, disease symptoms are often alleviated with GABA-agonistic benzodiazepines. Exogenous cannabinoids also modulate GABAergic signaling, and THC, one of the natural compounds that prompted the discovery of the endocannabinoid system mimics the effects of endogenous cannabinoids at endocannabinoid and non-cannabinoid sites in the …

Delivering Signal-Altering Bacterial Effector Proteins To Mammalian Cells Using Cell-Penetrating Peptide Technology, Robert Dickson

Master of Science in Integrative Biology Theses

A major role of the mitogen activated protein kinase (MAPK) pathway in eukaryotes is to activate the bacterial pathogen defense response upon the detection of bacterial products in the environment. This defensive signaling results in the induction of inflammation, the transcription of antimicrobial peptides, the modulation of the cell cycle and cell survival. Some Gram-negative bacteria have evolved needle-like structures called Type III Secretion Systems (T3SS) that secrete signal-altering molecules into the host cell to interrupt signaling pathways that would otherwise lead to the elimination of the bacterial infection. These signal-altering molecules are known as bacterial effector proteins (BEPs). Bacterial …

Understanding How Map Kinases Influence Endothelial Nitric-Oxide Synthase Activity, Xzaviar Solone

Master of Science in Integrative Biology Theses

Mitogen activated protein kinases (MAPK) p38 and ERK have both been reported to bind endothelial nitric oxide synthase (eNOS) with submicromolar affinity via proposed interactions with a pentabasic non-canonical MAPK binding sequence in the autoinhibitory insertion of eNOS. The neuronal isoform, which lacks the pentabasic motif, did not bind either MAPK significantly. In the present study, the pentabasic motif was validated using predictive modeling programming, and eNOS phosphorylation by MAPKs (P38, ERK and JNK) was examined using in vitro kinase assays and immunoblotting. JNK phosphorylation at Ser¹¹⁴ contrasts with ERK, which phosphorylated Ser⁶⁰⁰, and p38, which phosphorylated …

The Role Of Reactive Oxygen Species In Crotalus Atrox Venom-Induced Cell Death, Lindsay Brown

Master of Science in Integrative Biology Theses

Venomous snake bites impact humans all around the world. Anti-venom treatments mitigate systemic effects such as vascular hemorrhage, platelet aggregation inhibition, and the activation of inflammatory mediators. However, hemorrhagic snake venom also causes a loss of cellular adhesion to extracellular matrix components resulting in massive local tissue damage. To better understand the mechanism in which venom induces local tissue damage, human embryonic kidney cells (HEKS) were grown on PEI then stimulated with 500μg/ml Crotalus atrox (CA) venom for 4 and 10 hours. Alamar Blue assays were used to measure cell viability and results suggest a 15±8.6% (p<0.05) and 59±10.7% (p<0.05) reduction in cell viability at 4 and 10 hours, respectively. Cells stimulated with 500μg/ml venom for 10 hours stained 98±2.2% (p<0.05) positive for Trypan blue, suggesting the venom reduces membrane integrity. Identical treatment in the presence of 200 units PEG-catalase (PC) increased viability by 37±5.7% (p>0.001) compared to …

Health And Social Disparities Influence Opioid Misuse Among Adult Females Living In Rural Areas, Tequila Porter

Master of Science in Integrative Biology Theses

Since the early 1800s scientists have been working to create the best non-addictive pain medication derived from opium. In the early 1800s morphine was distilled from opium extracted from opium poppy plants (Quinones, 2015). Soon after a chemist invents a synthetic derivative of opium and names it diacetylmorphine (heroin) (Quinones, 2015, (Drugs and Morphine Text, 2018). Heroin originally was a safe cure for morphine addiction. Once this was proven to be false, and as having addictive properties, the government intervened and began initiatives to address the issue. This public crisis quickly grew to what modern scientists and healthcare professionals know …

Reproductive Life History And Shell Shape Variation Of Three Species Of Elimia (Pleuroceridae) In The Lower Etowah River Basin, Ellen Winant

Master of Science in Integrative Biology Theses

Pleurocerid snail diversity in the Southeastern United States is thought to be high, but estimates of overall diversity are compromised by uncertain taxonomy. This is particularly true for the genus Elimia, where reliance on conchological characters described by early naturalists for species designation failed to recognize significant variability in shell morphology. In this study we examine three putative species of Elimia to determine if quantifiable conchological characters are associated with differences in life history characteristics. Individuals of E. modesta, E. carinocostata, and E. cariniferawere collected from nine sites in three streams in the lower Etowah River …

The Role Of Cnd-1/Neurod1 In C. Elegans Nervous System Development, Wendy Aquino Nunez

Master of Science in Integrative Biology Theses

NeuroD1 is a vertebrate helix-loop-helix transcription factor that is involved in nervous system development and pancreatic islet development. NeuroD1 -/- mice is uncoordinated, has seizures and a reduce brain size (Miyata et al. 1999). In C. elegans, the ortholog gene is cnd-1. Hallam et al. 2000, showed that cnd-1 has a role in cell fate determination of GABAergic, DD motor neurons, in addition to a role in axon morphology. cnd-1(ju29) worms, show GABAergic motor neuron defect, they have a “kinky” backward movement phenotype and their axons are branched. However, only three genes are known to be downstream targets of …

Effects Of Drift Macroalgae On Sediment Nitrogen Cycling In Thalassia Testudinum Beds Of St. Joseph Bay, Fl, Erica Strope

Master of Science in Integrative Biology Theses

Anthropogenic nitrogen (N) loading and eutrophication can affect valuable ecosystem services and seagrass habitats by modifying structural and functional aspects of estuarine communities including increasing and prolonging macroalgae blooms. In some contexts, macroalgae may play a key role in N cycling pathways because they can alter sediment chemistry. Previous research has associated drift macroalgae blooms with elevated dissolved inorganic N concentrations in sediments as a result of increased remineralization of organic matter, but drift macroalgae effects on microbial N transformation pathways are not well understood. This study quantified the effects of macroalgae on estuarine N cycling in Thalassia testudinum seagrass …

Modeling And Mapping Addiction In The Zebrafish, Danio Rerio, Bradley Serpa

Master of Science in Integrative Biology Theses

Driven by the communication of dopamine, the vertebrate reward system has been evolutionarily conserved to maintain survival and optimize fitness. The neural circuits governing this system integrate sensory stimuli to produce appropriate, self-preserving responses that underlie experience-based learning. In the most primitive vertebrates, dopamine release in neuronal circuits drives homeostatic behaviors, such as seeking nutrients, finding a mate, or avoiding danger. From agnathans to mammals, dopaminergic synthesis and signaling genes and molecules, along with neuronal pathways and reward system-based behaviors, remain highly conserved. Dopamine signaling proteins include two classes of metabotropic G-Protein Receptor Coupled Dopamine Receptors, D1-like (DRD1) and D2-like …

Novel Applications Of Biolayer Interferometry To Investigate Molecular Interactions, Mareena M. Pitts

Master of Science in Integrative Biology Theses

In this study, BLI is used to explore various molecular interactions to demonstrate molecular binding and to provide quantitative characterization of binding kinetics and affinities of phage-protein and DNA-protein interactions. The results of this study demonstrate novel use of biolayer interferometry to immobilize whole Sf6 bacteriophage onto the biosensor to measure the binding to its outer membrane host receptor protein OmpA. The use of BLI also demonstrates the technology as a probe to predict and verify binding interactions at the molecular level to assign the role of protein function in both Vibrio fischeri and Pseudomonas aeruginosa. Each aim of this …

Selective Muscle Degeneration In A Drosophila Model Of Cachexia; A Role For The Transcriptional Regulator Cabut, Matthew Giedd

Master of Science in Integrative Biology Theses

Cachexia is a systemic metabolic syndrome characterized by progressive muscle wasting. Cachectic muscle wasting presents as a comorbidity with pathological illnesses like cancer, chronic inflammation, and type 2 diabetes. The development of cachexia complicates treatment of these diseases and worsens clinical outcomes. Thus, it has become the focus of intense investigation. While many of the upstream mechanisms that propagate cachectic muscle wasting have been brought to light, little is known of the downstream mechanisms which would be more clinically relevant. Here, we have adopted a Drosophila model of cachectic muscle wasting to elucidate a novel role of the transcriptional regulator, …

An Integrative Approach To Evaluating Radiocesium Contamination In Fukushima Prefecture, James Thornhill

Master of Science in Integrative Biology Theses

An earthquake in Japan led to the meltdown of the Fukushima Daiichi Nuclear Power Plant which released radionuclides into the surrounding regions. Of these radionuclides, cesium-137 (¹³⁷Cs⁺) has been shown to be the most abundant. Research has shown that adsorption of K⁺ and Cs⁺ on 2:1 clay minerals can collapse the interlayers, causing the adsorbed ion to become non-exchangeable. This thesis takes an integrative approach to the restoration of radiocesium-contaminated soil in three parts by 1) evaluating the adsorption behavior and mechanisms of Cs⁺ in vermiculite, 2) using plants as bioindicators to elucidate …

Transcending The Cell Fate Stereotype: Cell Penetrating Peptide Technology Helps Induce Pluripotency In Multiple Cell Types, Kelsey Clearman

Master of Science in Integrative Biology Theses

Induced pluripotent stem cells (iPSCs) are one of the most promising new technologies in the field of regenerative medicine. iPSCs can be generated directly from a patient’s own fibroblast cells then converted into any cell type, thus overcoming challenges associated with embryonic stem cells and graft-vs-host disease that result from current methods. Generation of iPSCs from fibroblasts is traditionally accomplished by ectopic expression of four key transcription factors (TFs): Oct4, Sox2, Klf4, and c-Myc also known as OSKM. These TFs have been shown to be involved in maintaining pluripotency and inhibiting embryonic stem (ES) cell differentiation. Reprogramming fibroblasts into iPSCs …

Evolution Of Voltage-Gated Ion Channels, Kevin Gregory Bennett, Kevin Bennett

Master of Science in Integrative Biology Theses

Voltage-gated Ion Channels (VICs) form a superfamily of energy-independent membrane transporters that facilitate the transfer of charged sodium, calcium, and potassium ions across the cell membrane (Hodgkin & Huxley 1952). The channels contain a selective ion-conducting pore along with several other structural and gating features that come together to form a functional hetero- or homotetramer. A comprehensive phylogenetic study of all available proteins aimed at finding unknown distribution and illuminating evolutionary paths would be immensely useful in understanding relationships of structure, function, and organismal distribution. This phylogenetic analysis of VICs will be immensely useful in characterizing functional and structural distribution, …