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Biochemistry, Biophysics, and Structural Biology

2020

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Articles 1 - 30 of 109

Full-Text Articles in Biology

Identification Of Clonal Evolution Pattern And Mutation Event Associated With Relapsed/Refractory Diffuse Large B-Cell Lymphoma Using Next-Generation Sequencing, Cheng Wang Dec 2020

Identification Of Clonal Evolution Pattern And Mutation Event Associated With Relapsed/Refractory Diffuse Large B-Cell Lymphoma Using Next-Generation Sequencing, Cheng Wang

Theses & Dissertations

Diffuse large B-cell lymphoma (DLBCL) is an aggressive lymphoid malignancy. About 30% of DLBCL cases respond poorly to initial treatment and eventually relapse. For these patients, the current treatment regimen is quite limited, and the prognosis is poor. Gene mutations and genetic alterations play an important role in lymphomagenesis. However, the genetic alterations or gene mutations underlying the disease resistance/relapse in DLBCL are still unknown. The clonal evolution during the process of disease progression is elusive as well. Our goal is to study the genetic alterations in DLBCL, particularly paired diagnostic and relapsed/refractory DLBCL, to better understand the mutation landscape …


Mechanisms By Which Mnte-2-Pyp Suppresses Prostate Cancer Cell Growth, Yuxiang Zhu Dec 2020

Mechanisms By Which Mnte-2-Pyp Suppresses Prostate Cancer Cell Growth, Yuxiang Zhu

Theses & Dissertations

Prostate cancer patients are often treated with radiotherapy. MnTE-2-PyP, is a superoxide dismutase (SOD) mimic and a known radioprotector of normal tissues. Our recent work demonstrates that MnTE-2-PyP also inhibits prostate cancer progression with radiotherapy; however, the mechanisms remain unclear. In this thesis, we identified that MnTE-2-PyP-induced intracellular H2O2 levels are critical in inhibiting growth of prostate cancer cells. We found that MnTE-2-PyP induced protein oxidations in PC3 cells and one major group of oxidized protein targets were involved in energy metabolism. The oxidative phosphorylation rates were significantly enhanced in both PC3 and LNCaP cells with MnTE-2-PyP treatment, but mitochondrial …


Engineering Mesothelin-Binding Proteins As Targeted Cancer Diagnostics And Therapeutics, Allison Rita Sirois Dec 2020

Engineering Mesothelin-Binding Proteins As Targeted Cancer Diagnostics And Therapeutics, Allison Rita Sirois

Doctoral Dissertations

Cancer is a significant global health concern; and traditional therapies, including chemotherapeutics, are often simultaneously toxic yet ineffective. There is a critical need to develop targeted cancer therapeutics which specifically inhibit molecules or molecular pathways essential for tumor growth and maintenance. Furthermore, a targeted therapy is only effective when a patient's tumor expresses the molecular target; therefore, companion diagnostics, including molecular imaging agents, are a necessary counterpart of targeted therapies. Mesothelin (MSLN) is a cell surface protein overexpressed in numerous cancers, including triple-negative breast, pancreatic, ovarian, liver, and lung, with limited expression in normal tissues. Aberrant MSLN expression promotes tumor …


Elucidating The Role Of Ecdysoneless In Mrna Processing, Irfana Saleem Dec 2020

Elucidating The Role Of Ecdysoneless In Mrna Processing, Irfana Saleem

Theses & Dissertations

The mammalian orthologue of the evolutionarily conserved Ecdysoneless (ECD) protein is required for embryogenesis, cell cycle progression and mitigation of ER stress. However, the molecular mechanisms of ECD function in mammalian cells remain unclear. Here, using mass spectrometry analysis of the mammalian ECD interactome, we identified several components of the mRNA export complexes as binding partners of ECD and then characterized the functional interaction of ECD with key mRNA export-related DEAD BOX protein helicase DDX39A and its associated partners. FISH analysis of Poly-A-tailed mRNAs revealed that ECD depletion/deletion blocks the mRNA export from the nucleus to the cytoplasm. We have …


Physical Drivers Facilitating A Toxigenic Cyanobacterial Bloom In A Major Great Lakes Tributary, Paul G. Matson, Gregory L. Boyer, Thomas B. Bridgeman, George S. Bullerjahn, Douglas D. Kane, Robert M.L. Mckay, Katelyn M. Mckindles, Heather A. Raymond, Brenda K. Snyder, Richard P. Stumpf, Timothy W. Davis Dec 2020

Physical Drivers Facilitating A Toxigenic Cyanobacterial Bloom In A Major Great Lakes Tributary, Paul G. Matson, Gregory L. Boyer, Thomas B. Bridgeman, George S. Bullerjahn, Douglas D. Kane, Robert M.L. Mckay, Katelyn M. Mckindles, Heather A. Raymond, Brenda K. Snyder, Richard P. Stumpf, Timothy W. Davis

Great Lakes Institute for Environmental Research Publications

The Maumee River is the primary source for nutrients fueling seasonal Microcystis-dominated blooms in western Lake Erie's open waters though such blooms in the river are infrequent. The river also serves as source water for multiple public water systems and a large food services facility in northwest Ohio. On 20 September 2017, an unprecedented bloom was reported in the Maumee River estuary within the Toledo metropolitan area, which triggered a recreational water advisory. Here we (1) explore physical drivers likely contributing to the bloom's occurrence, and (2) describe the toxin concentration and bacterioplankton taxonomic composition. A historical analysis using 10-years …


Finding The Balance​ The Effects Of Α-Cyclodextrin, 2-Hydroxypropyl-Β-Cyclodextrin, And Cholesterol Bacteroides Vulgatus And Clostridium Bolteae​, Bethany Weaver Dec 2020

Finding The Balance​ The Effects Of Α-Cyclodextrin, 2-Hydroxypropyl-Β-Cyclodextrin, And Cholesterol Bacteroides Vulgatus And Clostridium Bolteae​, Bethany Weaver

Pence-Boyce STEM Student Scholarship

Atherosclerosis is a cardiovascular disease that is characterized by the hardening of arteries through the formation of cholesterol plaques. Cyclodextrins could potentially treat atherosclerosis by shrinking plaques. These cyclic oligosaccharides can make complexes with cholesterol but have also shown toxic side effects. This study looked for potential negative effects of cyclodextrins and cholesterol on gut bacteria. It was hypothesized that Bacteroides vulgatus will have decreased growth when grown in broth with cholesterol. In contrast, Clostridium bolteae will have decreased growth when grown in broth with cyclodextrins. Due to the fact that these bacteria are anaerobic, Clostridium bolteae and Bacteroides vulgatus …


Sine Oculis Homeobox Homolog 1 (Six1) Plays A Critical Role In The Progression Of Pulmonary Fibrosis., Cory Wilson Dec 2020

Sine Oculis Homeobox Homolog 1 (Six1) Plays A Critical Role In The Progression Of Pulmonary Fibrosis., Cory Wilson

Dissertations & Theses (Open Access)

Idiopathic pulmonary fibrosis (IPF) is the most common idiopathic interstitial pneumonia with a median survival time of 2-4 years after diagnosis. The alarming mortality rate is due to the lack of effective treatments. IPF is a chronic disease that is characterized by alveolar destruction due to increasing extracellular matrix deposition that leads to poor lung compliance, impaired gas exchange, and ultimately respiratory failure. Repetitive alveolar epithelial injury is a central process to the underlying pathology with injury to the type II alveolar epithelial cells (AT2) specifically being a key player in the pathogenesis of IPF. Recent studies have shown that …


The Effect Of Nuclear Perturbations On The 3d Organization Of The Genome, Rosela Golloshi Dec 2020

The Effect Of Nuclear Perturbations On The 3d Organization Of The Genome, Rosela Golloshi

Doctoral Dissertations

Cells in our body experience constant mechanical forces that influence biological functions such as growth and development. The nucleus has been implicated as a key mechanosensor and can directly influence chromatin organization and epigenetic alterations leading to gene expression changes. However, the mechanism by which such mechanical forces lead to genomic alterations and expression of mechanosensitive genes is not fully understood. The work presented in this dissertation investigates the effect of mechanical and epigenetic perturbations on the 3D genome organization. To investigate this 3D genome folding, we use Chromosome Conformation Capture followed by high throughput sequencing (Hi-C) (Chapter-1) which identifies …


Drivers Of Rickettsial Pathogen Transmission And Spillover In Local Tick Populations In Southeastern Virginia, Alexandra Cumbie Dec 2020

Drivers Of Rickettsial Pathogen Transmission And Spillover In Local Tick Populations In Southeastern Virginia, Alexandra Cumbie

Biomedical Sciences Theses & Dissertations

Cases of spotted fever group rickettsiosis are becoming more prevalent in the United States. In Virginia, there are three human-biting ticks which are largely responsible for the spread of rickettsial pathogens and the increase in disease cases. These species include Dermacentor variabilis, Amblyomma americanum, and Amblyomma maculatum; all of which are vectors of rickettsial agents to vertebrate hosts. These species are sympatric as adults and have the potential to share large and small mammal hosts. Their interactions on and off host and their associated rickettsiae were the focus of this dissertation work. Amblyomma americanum is the vector …


Dna Aptamer-Drug Targeting Chemotherapy: Investigation Of Cell Cycle Inhibition Via S15 Aptamer – Norcantharidin Complex, Shannon Fehr Nov 2020

Dna Aptamer-Drug Targeting Chemotherapy: Investigation Of Cell Cycle Inhibition Via S15 Aptamer – Norcantharidin Complex, Shannon Fehr

Senior Honors Theses

Lung Cancer is the leading cause of cancer related death in both men and women in the United States (Bray et al., 2018). Cancer treatments are often non-specific and kill many dividing cells within a patient causing unwanted side effects. Norcantharidin (NCTD) is a synthetic FDA approved treatment for cancers including non-small cell lung cancers (NSCLC). NCTD suppresses cell proliferation by inhibiting cells from exiting the G2 phase of the cell cycle. Aptamers are short single-stranded DNA or RNA molecules with ligand directed self-annealing capabilities allowing selective binding to specific targets. This paper will discuss the hypothesized effects of using …


Posttranslational Modification And Protein Disorder Regulate Protein-Protein Interactions And Dna Binding Specificity Of P53, Robin Levy Nov 2020

Posttranslational Modification And Protein Disorder Regulate Protein-Protein Interactions And Dna Binding Specificity Of P53, Robin Levy

USF Tampa Graduate Theses and Dissertations

p53 is an intrinsically disordered transcription factor that suppresses tumor development by arresting the cell cycle and promoting DNA repair. p53 deletions or mutations can lead to cancer due to the inability of cells to respond to stress. The protein levels and post-translational modification state of p53 changes in response to cellular stress like DNA damage. Previous studies have shown that p53 can undergo coupled folding and binding with the E3 ubiquitin ligase, Mdm2, and the histone deacetylase, p300. In normal cells, p53 is kept at a low level by Mdm2, which marks it with ubiquitin, targeting p53 for proteasome …


Dissolved Microcystin Release Coincident With Lysis Of A Bloom Dominated By Microcystis Spp. In Western Lake Erie Attributed To A Novel Cyanophage, Katelyn M. Mckindles, Makayla A. Manes, Jonathan R. Demarco, Andrew Mcclure, R. Michael Mckay, Timothy W. Davis, George S. Bullerjahn Nov 2020

Dissolved Microcystin Release Coincident With Lysis Of A Bloom Dominated By Microcystis Spp. In Western Lake Erie Attributed To A Novel Cyanophage, Katelyn M. Mckindles, Makayla A. Manes, Jonathan R. Demarco, Andrew Mcclure, R. Michael Mckay, Timothy W. Davis, George S. Bullerjahn

Great Lakes Institute for Environmental Research Publications

Western Lake Erie (Laurentian Great Lakes) is prone to annual cyano- bacterial harmful algal blooms (cHABs) dominated by Microcystis spp. that often yield microcystin toxin concentrations exceeding the federal EPA recreational con-tact advisory of 8 μg liter-1. In August 2014, microcystin levels were detected in fin-ished drinking water above the World Health Organization 1.0 μg liter-1 threshold for consumption, leading to a 2-day disruption in the supply of drinking water for >400,000 residents of Toledo, Ohio (USA). Subsequent metatranscriptomic analysis of the 2014 bloom event provided evidence that release of toxin into the water sup-ply was likely caused by cyanophage …


Mimicking Transgenerational Signals Of Future Stress: Thermal Tolerance Of Juvenile Chinook Salmon Is More Sensitive To Elevated Rearing Temperature Than Exogenously Increased Egg Cortisol, Theresa R. Warriner, Christina A.D. Semeniuk, Trevor E. Pitcher, Daniel D. Heath, Oliver P. Love Oct 2020

Mimicking Transgenerational Signals Of Future Stress: Thermal Tolerance Of Juvenile Chinook Salmon Is More Sensitive To Elevated Rearing Temperature Than Exogenously Increased Egg Cortisol, Theresa R. Warriner, Christina A.D. Semeniuk, Trevor E. Pitcher, Daniel D. Heath, Oliver P. Love

Great Lakes Institute for Environmental Research Publications

Elevated temperatures resulting from climate change are expected to disproportionately affect ectotherms given their biological function has a direct link to environmental temperature. Thus, as climate change leads to rapid increases in water temperatures in rivers, aquatic ectotherms, such as fish may be highly impacted. Organisms can respond to these stressors through flexible and rapid phenotypic change induced via developmental and/or transgenerational plasticity. In oviparous species, gravid females may translate environmental stress across generations via increased exposure of eggs to maternally derived glucocorticoids (i.e., maternal stress), which has been shown to result in diverse phenotypic effects in offspring. Recent studies …


Axonal Blockage With Microscopic Magnetic Stimulation, Hui Ye Oct 2020

Axonal Blockage With Microscopic Magnetic Stimulation, Hui Ye

Biology: Faculty Publications and Other Works

Numerous neurological dysfunctions are characterized by undesirable nerve activity. By providing reversible nerve blockage, electric stimulation with an implanted electrode holds promise in the treatment of these conditions. However, there are several limitations to its application, including poor bio-compatibility and decreased efficacy during chronic implantation. A magnetic coil of miniature size can mitigate some of these problems, by coating it with biocompatible material for chronic implantation. However, it is unknown if miniature coils could be effective in axonal blockage and, if so, what the underlying mechanisms are. Here we demonstrate that a submillimeter magnetic coil can reversibly block action potentials …


Fine-Tuning Of Alanyl-Trna Synthetase Quality Control Alleviates Global Dysregulation Of The Proteome, Paul Kelly, Arundhati Kavoor, Michael Ibba Oct 2020

Fine-Tuning Of Alanyl-Trna Synthetase Quality Control Alleviates Global Dysregulation Of The Proteome, Paul Kelly, Arundhati Kavoor, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

One integral step in the transition from a nucleic acid encoded-genome to functional proteins is the aminoacylation of tRNA molecules. To perform this activity, aminoacyl-tRNA synthetases (aaRSs) activate free amino acids in the cell forming an aminoacyl-adenylate before transferring the amino acid on to its cognate tRNA. These newly formed aminoacyl-tRNA (aa-tRNA) can then be used by the ribosome during mRNA decoding. In Escherichia coli, there are twenty aaRSs encoded in the genome, each of which corresponds to one of the twenty proteinogenic amino acids used in translation. Given the shared chemicophysical properties of many amino acids, aaRSs have …


Role Of Ceramide-1 Phosphate In Regulation Of Sphingolipid And Eicosanoid Metabolism In Lung Epithelial Cells, Brittany A. Dudley Oct 2020

Role Of Ceramide-1 Phosphate In Regulation Of Sphingolipid And Eicosanoid Metabolism In Lung Epithelial Cells, Brittany A. Dudley

USF Tampa Graduate Theses and Dissertations

Ceramide 1-Phosphate (C1P) is a sphingolipid metabolite which plays a large role in inflammation, cell survival and proliferation1. C1P is known to have both pro- and anti-apoptotic roles in lung cancer cells, governed by ceramide kinase (CERK), upstream of precursor ceramide (Cer)2. Previous work reveals C1P serves as the liaison between sphingolipid and eicosanoid synthesis, by decreasing the dissociation rate of group IVA cytosolic PLA2 (cPLA) from the Golgi membrane, C1P directly activates this phospholipase for downstream eicosanoid synthesis and subsequent inflammatory response3. CERK has been discovered to modulate eicosanoid synthesis, …


Molecular Identification And Characterization Of Viral Pathogens Infecting Sweet Cherry, Aaron J. Simkovich Oct 2020

Molecular Identification And Characterization Of Viral Pathogens Infecting Sweet Cherry, Aaron J. Simkovich

Electronic Thesis and Dissertation Repository

Stone fruits are a valuable crop grown worldwide, however pathogens such as viruses threaten fruit production by reducing tree health and fruit yield. In an orchard within the Niagara region of Ontario, symptoms typical of viral infection such as chlorosis and leaf deformation were seen on sweet cherry (Prunus avium L.) trees. Next generation sequencing was performed on symptomatic and asymptomatic leaves and four viruses were identified. On the tree displaying the most severe symptoms, Prune dwarf virus (PDV), was the only virus detected. A survey conducted during this work showed 42% of cherry trees on a single …


Comparing Temporal Patterns In Body Condition Of Ringed Seals Living Within Their Core Geographic Range With Those Living At The Edge, Steven H. Ferguson, David J. Yurkowski, Brent G. Young, Aaron T. Fisk, Derek C.G. Muir, Xinhua Zhu, Gregory W. Thiemann Oct 2020

Comparing Temporal Patterns In Body Condition Of Ringed Seals Living Within Their Core Geographic Range With Those Living At The Edge, Steven H. Ferguson, David J. Yurkowski, Brent G. Young, Aaron T. Fisk, Derek C.G. Muir, Xinhua Zhu, Gregory W. Thiemann

Great Lakes Institute for Environmental Research Publications

Ecological theory suggests that demographic responses by populations to environmental change vary depending on whether individuals inhabit central or peripheral regions within the species’ geographic range. Here, we tested this prediction by comparing a population of ringed seals Pusa hispida located at high latitudes as part of their core range (core) with a population located at the southern extremity of their range (peripheral). First, we compared the two regions’ environmental trends in timing of sea-ice breakup and freeze-up, open-water duration and the North Atlantic Oscillation (NAO). We found that the core region shifted to progressively warmer conditions in the early …


A Review Of The Preclinical And Clinical Efficacy Of Remdesivir, Hydroxychloroquine, And Lopinavir-Ritonavir Treatments Against Covid-19, Dawid Maciorowski, Samir Z. El Idrissi, Yash Gupta, Brian J. Medernach, Michael B. Burns, Daniel P. Becker Ph.D., Ravi Durvasula, Prakasha Kempaiah Sep 2020

A Review Of The Preclinical And Clinical Efficacy Of Remdesivir, Hydroxychloroquine, And Lopinavir-Ritonavir Treatments Against Covid-19, Dawid Maciorowski, Samir Z. El Idrissi, Yash Gupta, Brian J. Medernach, Michael B. Burns, Daniel P. Becker Ph.D., Ravi Durvasula, Prakasha Kempaiah

Chemistry: Faculty Publications and Other Works

In December of 2019, an outbreak of a novel coronavirus flared in Wuhan, the capital city of the Hubei Province, China. The pathogen has been identified as a novel enveloped RNA beta-coronavirus named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The virus SARS-CoV-2 is associated with a disease characterized by severe atypical pneumonia known as coronavirus 2019 (COVID-19). Typical symptoms of this disease include cough, fever, malaise, shortness of breath, gastrointestinal symptoms, anosmia, and, in severe cases, pneumonia.1 The high-risk group of COVID-19 patients includes people over the age of 60 years as well as people with existing cardiovascular …


Foraging Tactics In Dynamic Sea-Ice Habitats Affect Individual State In A Long-Ranging Seabird, Arnaud Tarroux, Yves Cherel, Per Fauchald, Akiko Kato, Oliver P. Love, Yan Ropert-Coudert, Gunnar Spreen, Øystein Varpe, Henri Weimerskirch, Nigel G. Yoccoz, Sandrine Zahn, Sébastien Descamps Sep 2020

Foraging Tactics In Dynamic Sea-Ice Habitats Affect Individual State In A Long-Ranging Seabird, Arnaud Tarroux, Yves Cherel, Per Fauchald, Akiko Kato, Oliver P. Love, Yan Ropert-Coudert, Gunnar Spreen, Øystein Varpe, Henri Weimerskirch, Nigel G. Yoccoz, Sandrine Zahn, Sébastien Descamps

Great Lakes Institute for Environmental Research Publications

Individual heterogeneity in diet and foraging behaviour is common in wild animal populations, and can be a strong determinant of how populations respond to environmental changes. Within populations, variation in foraging behaviour and the occurrence of individual tactics in relation to resources distribution can help explain differences in individual fitness, and ultimately identify important factors affecting population dynamics. We examined how foraging behaviour and habitat during the breeding period related to the physiological state of a long-ranging seabird adapted to sea ice, the Antarctic petrel Thalassoica antarctica. Firstly, using GPS tracking and state-switching movement modelling (hidden Markov models) on 124 …


Mechanisms Of Cross-Presentation By Cdc1s, Derek James Theisen Aug 2020

Mechanisms Of Cross-Presentation By Cdc1s, Derek James Theisen

Arts & Sciences Electronic Theses and Dissertations

Classical dendritic cells (cDCs) are specialized antigen presenting cells that can be divided into distinct subsets based on the types of pathogens they respond to and the type of immune response they generate. The cDC1 subset is specialized in priming CD8 T cell responses through the process of cross-presentation. During cross-presentation, exogenous protein antigens are taken up by cDC1 and presented on MHCI molecules, allowing for the priming of CD8 T cells during conditions when DCs themselves are not directly infected. The ability to cross-present in vivo is unique to cDC1, and is essential for anti-viral responses and rejection of …


Testing The Combined Module Swapping And Repair By Modification Strategies: A Step Toward Universal Toolbox, Catherine A. Martini Aug 2020

Testing The Combined Module Swapping And Repair By Modification Strategies: A Step Toward Universal Toolbox, Catherine A. Martini

Biology Theses

The crux of synthetic biology is the engineering of biological components to modulate the activity of specific DNA-based promoter(s) to drive gene expression; thus, providing a means to modulate pathways between signal detection and cellular response. However, the longstanding frustration of synthetic biologists has been the inability to transfer those engineered components between cellular systems — this lack of “modular universality” or “universal toolbox” impedes research by forcing a metaphorical reinvention of the wheel in new systems. The modular swapping strategy expanded the available “toolbox” with customizable hybrid repressors formed from “swapping” the DNA-recognition modules (DRMs) and environmental-sensing modules (ESMs) …


Identification Of Predation Events In Wild Fish Using Novel Acoustic Transmitters, Amy A. Weinz, Jordan K. Matley, Natalie V. Klinard, Aaron T. Fisk, Scott F. Colborne Aug 2020

Identification Of Predation Events In Wild Fish Using Novel Acoustic Transmitters, Amy A. Weinz, Jordan K. Matley, Natalie V. Klinard, Aaron T. Fisk, Scott F. Colborne

Great Lakes Institute for Environmental Research Publications

Background: Acoustic telemetry is a commonly used tool to gain knowledge about aquatic animal ecology through the study of their movements. In telemetry studies researchers must make inferences regarding the movements and the fates of tagged animals. Until recently, predation has been inferred in telemetry data using a variety of methods including abrupt changes in movement patterns or habitat use. An acoustic telemetry transmitter has been developed to detect predation events of tagged animals, and while they have performed well in controlled laboratory trials, literature regarding the application of these novel transmitters in field settings is limited. The objective of …


Structure And Evolution Of Lizard Immunity Genes, Trent Santonastaso Aug 2020

Structure And Evolution Of Lizard Immunity Genes, Trent Santonastaso

University of New Orleans Theses and Dissertations

One of the most important gene families to play a role in adaptive immunity is the major histocompatibility complex (MHC). MHC class II loci are considered to be the most variable loci in the vertebrate genome, and studies have shown that this variability can be maintained through complex co-evolutionary dynamics between host and parasite. Despite the rich body of research into the MHC, there is comparatively little understanding of its genomic architecture in reptiles. Similarly, loci associated with innate immunity have received little attention in reptiles compared to other vertebrates. In the first chapter, we investigated the structure and organization …


Community Dynamics And Function Of Algae And Bacteria During Winter In Central European Great Lakes, George S. Bullerjahn, Robert Michael L. Mckay, Gábor Bernát, Ondřej Prášil, Lajos Vörös, Károly Pálffy, Nóra Tugyi, Boglárka Somogyi Aug 2020

Community Dynamics And Function Of Algae And Bacteria During Winter In Central European Great Lakes, George S. Bullerjahn, Robert Michael L. Mckay, Gábor Bernát, Ondřej Prášil, Lajos Vörös, Károly Pálffy, Nóra Tugyi, Boglárka Somogyi

Great Lakes Institute for Environmental Research Publications

Abundant phytoplankton and bacteria were identified by microscopy and high-throughput 16S rRNA tag Illumina sequencing of samples from water- and ice phases collected during winter at two central European Great Lakes, Balaton and Fertő (Neusiedlersee). Bacterial reads at all sites were dominated (>85%) by Bacteroidetes and Proteobacteria. Amongst phototrophs, microscopy and 16S sequencing revealed that both phytoplankton and cyanobacteria were represented, with a median of 1500 cyanobacterial sequence reads amongst 13 samples analyzed. The sequence analysis compared replicate Balaton and Fertő ice and water samples with an outgroup from three Hungarian soda lakes. In particular, both water and ice …


Transcriptional Control Of Virulence Genes In The Bacterial Pathogen Shigella Flexneri, Joy Asami Mckenna Aug 2020

Transcriptional Control Of Virulence Genes In The Bacterial Pathogen Shigella Flexneri, Joy Asami Mckenna

UNLV Theses, Dissertations, Professional Papers, and Capstones

Shigella species, the causal agents of bacillary dysentery, use a type III secretion system (T3SS) to inject two waves of virulence proteins, known as effectors, into the human colonic epithelium to subvert host cell machinery. Transcriptional regulation of these virulence genes is controlled by the three-tiered VirF/VirB/MxiE signaling cascade. Of these, VirB has the largest regulon (~50 genes); however, VirB regulatory properties are poorly understood. To date, VirB is known to function to counter or 'anti-silence' transcriptional silencing mediated by the histone-like nucleoid structuring protein H-NS. To better understand VirB regulation, my colleagues and I chose to better define the …


No Oxygen, No Water: The Unique Physiology Of Annual Killifish Embryos Across Development, Daniel Erik Zajic Jul 2020

No Oxygen, No Water: The Unique Physiology Of Annual Killifish Embryos Across Development, Daniel Erik Zajic

Dissertations and Theses

For most vertebrates, an abundance of oxygen is necessary for the production of ATP and the maintenance of cellular homeostasis. The absence of oxygen, even for brief periods, quickly leads to ATP depletion which can lead to irreparable damages to sensitive organs, such as the brain and heart. However, certain vertebrates demonstrate an extraordinary ability to thrive and recover fully from periods of no oxygen (anoxia). The annual killifish (Austrofundulus limnaeus) lives in ephemeral ponds in the Maracaibo basin of Venezuela and their embryos have the remarkable ability to not only survive anoxic periods for months, but also …


Origin Of Gene Specificity In The Nitrogen-Fixing Symbiosis, Christina Marie Stonoha-Arther Jul 2020

Origin Of Gene Specificity In The Nitrogen-Fixing Symbiosis, Christina Marie Stonoha-Arther

Doctoral Dissertations

Many legumes form a symbiosis with nitrogen-fixing bacteria found in the soil. This relationship is beneficial to both the plant and the bacteria; the plant receives nitrogen that is otherwise limited, and the bacteria receive fixed carbon. Upon sensing the bacteria, the plant forms a new organ (the nodule) where the bacteria are housed within the cells. Many genes are required for the proper formation and function of nodules; this dissertation is broadly focused on how genes required for nitrogen-fixing symbiosis are co-opted from other cellular processes and how they are specialized for symbiosis. Protein trafficking from the plant to …


Characterization Of The Overexpression Of The Native H+-Pumping Pyrophosphatase In The Microalga Picochlorum Soloecismus, Kimberly T. Wright Jul 2020

Characterization Of The Overexpression Of The Native H+-Pumping Pyrophosphatase In The Microalga Picochlorum Soloecismus, Kimberly T. Wright

Biology ETDs

Microalgae are of interest for the creation of sustainable and cost competitive alternatives to petroleum-based fuels and chemicals. However, cultivation, extraction and processing of algal biomass requires improved yields to achieve economic feasibility. The advancement of microalgal biotechnology and various genetic engineering techniques allow the improvement of microalgae biomass for this purpose. Here, the characterization of the overexpression of the native vacuolar H+ pumping pyrophosphate (AVP1) in Picochlorum soloecismus was examined. AVP1 overexpression causes biomass increase in relevant plant crops. When overexpressed in this microalga it increases carbon storage in the form of starch in a closed laboratory photobioreactor. However, …


Plankton Dynamics In An Urban, Subtropical Lake Prior To Lake Restoration, Jennifer C. Pulsifer Jul 2020

Plankton Dynamics In An Urban, Subtropical Lake Prior To Lake Restoration, Jennifer C. Pulsifer

LSU Master's Theses

This research assessed plankton dynamics in two urban, subtropical lakes (University Lake and City Park Lake) shortly before a proposed and approved lake restoration project. Plankton dynamics were determined in University Lake by the dilution method to attempt to quantify growth rates of phytoplankton and grazing rates of zooplankton. Landry and Hassett’s (1982) dilution method has been widely used in marine systems to estimate rates of growth and grazing. In many marine systems, nutrients must be added to prevent nutrient limitation. However, it is assumed, due to the hypereutrophic conditions, that nutrients would not be a limitation in University Lake. …