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Glycogen Accumulation By Wild Type And Bald Mutant Strains Of Streptomyces Sp. Sfb5a During Growth On 3-Hydroxybutyrate, MacKenzie Francis 2020 Bridgewater College

Glycogen Accumulation By Wild Type And Bald Mutant Strains Of Streptomyces Sp. Sfb5a During Growth On 3-Hydroxybutyrate, Mackenzie Francis

Honors Projects

Previous research has shown that Streptomyces sp. SFB5A produces PHA depolymerase and forms aerial hyphae, while the bld4 mutant of this species forms aerial hyphae very poorly and does not produce PHA depolymerase. This effect may be due to the mutant’s inability to sense starvation. Therefore, we hypothesized that the bld4 may also be deficient in formation of glycogen and spores, which are both associated with starvation. To test this hypothesis, we grew the wild type (WT) Streptomyces sp. SFB5A and bld4 in broth cultures containing 3HB. We compared 3HB consumption, glycogen accumulation, PHA depolymerase synthesis, protein accumulation, and spore …


The Effects Of Storage Temperature On The Bovine Nasal Microbiome, Hunter Usdrowski 2020 University of Arkansas, Fayetteville

The Effects Of Storage Temperature On The Bovine Nasal Microbiome, Hunter Usdrowski

Animal Science Undergraduate Honors Theses

Bovine respiratory disease (BRD) is one of the largest economic burdens facing United States beef producer’s modern day. The complexity in the onset and development of this multifactorial disease necessitates further insights into its functions to alleviate the tremendous consequences it generates for producers. The respiratory microbiome and their metabolomics play an important role to maintain health and predict BRD. However, due to low biomass, new technology is needed to increase the microbial concentration for omics (e.g. metatranscriptomics) research. In this study, a novel self-enrichment storage technique on the bovine nasal microbiome was performed and compared to a traditional nasal …


Modulation Of Host Innate Immune Cells By Yersinia Pestis To Create A Permissive Environment For Replication., Amanda Rose Pulsifer 2020 University of Louisville

Modulation Of Host Innate Immune Cells By Yersinia Pestis To Create A Permissive Environment For Replication., Amanda Rose Pulsifer

Electronic Theses and Dissertations

Yersinia pestis has gained widespread infamy due to the historic outbreak during the middle ages, referred to as The Black Death. Infection with Y. pestis typically begins with deposition of Y. pestis into the dermis (bubonic plague) or respiratory tract (pneumonic plague). Tissue resident macrophages are the first innate immune cell encountered by Y. pestis. Macrophages are likely a way for Y. pestis to avoid neutrophils early in infection when the neutrophil neutralizing Type Three Secretion System is not expressed. This work focuses on which Rab host proteins are manipulated by Y. pestis, and how neutrophils are forced to …


The Effects Of An Applied Phyllosphere-Microbiome On Gas Exchange And Growth Of Soybean Infected With Pseudomonas Syringae: Harnessing The Power Of The Microbiome, Charles Agbavor 2020 Missouri State University

The Effects Of An Applied Phyllosphere-Microbiome On Gas Exchange And Growth Of Soybean Infected With Pseudomonas Syringae: Harnessing The Power Of The Microbiome, Charles Agbavor

Graduate Theses/Dissertations

The microbiome is an important determinant of plant health, growth and resistance to stress. This study was conducted to determine the efficacy of the phyllosphere-microbiome on managing Pseudomonas syringae pv. Glycinea (Psg), gas exchange and growth of Glycine max L. Merrill. A greenhouse study was conducted in the summer of 2019. A field isolated and cultured soybean phyllosphere-microbiome was applied to purposely infected and uninfected soybean. Gas exchange, Psg density, chlorophyll concentrations, and percent nitrogen and carbon in the leaves were measured during the V3-V6 stages of soybean. Not surprisingly, there was a two-fold reduction in copies of Pseudomonas …


Surface Runoff Alters Cave Microbial Community Structure And Function, Madison Davis, Maria A. Messina, Giuseppe Nicolosi, Salvatore Petralia, Melvin D. Baker, Christiana K. S. Mayne, Chelsea M. Dinon, Christina J. Moss, Bogdan P. Onac, James R. Garey 2020 University of South Florida

Surface Runoff Alters Cave Microbial Community Structure And Function, Madison Davis, Maria A. Messina, Giuseppe Nicolosi, Salvatore Petralia, Melvin D. Baker, Christiana K. S. Mayne, Chelsea M. Dinon, Christina J. Moss, Bogdan P. Onac, James R. Garey

Molecular Biosciences Faculty Publications

Caves formed by sulfuric acid dissolution have been identified worldwide. These caves can host diverse microbial communities that are responsible for speleogenesis and speleothem formation. It is not well understood how microbial communities change in response to surface water entering caves. Illumina 16S rRNA sequencing and bioinformatic tools were used to determine the impact of surface water on the microbial community diversity and function within a spring pool found deep in the Monte Conca Cave system in Sicily, Italy. Sulfur oxidizers comprised more than 90% of the microbial community during the dry season and were replaced by potential anthropogenic contaminants …


A Review Of Human Immunodeficiency Virus, Sophie Silver 2020 Liberty University

A Review Of Human Immunodeficiency Virus, Sophie Silver

Senior Honors Theses

Human immunodeficiency virus, also referred to as HIV, is a devastating virus which has infected millions. Characterized as a retrovirus, HIV has an RNA genome, which is reverse transcribed into DNA upon entry into the host cell. HIV primarily affects CD4+ T cells and is diagnosed by the significant reduction of CD4+ T cells. While no cure has been discovered yet, antiretroviral therapy (ART) has been demonstrated as an effective treatment option. In the progression of HIV, additional HIV-associated diseases may arise, including HIV-associated psoriasis and sensory neuropathy. In addition to the use of ART, clinicians often prescribe …


The Effects Of Light On The Bacterial Biomass Of Decomposing Leaf Litter In Freshwater, Savannah L. Underwood 2020 The University of Southern Mississippi

The Effects Of Light On The Bacterial Biomass Of Decomposing Leaf Litter In Freshwater, Savannah L. Underwood

Honors Theses

Recent evidence has suggested that the presence of light (and in conjuction, periphytic algae) stimulates the growth and production of bacteria on decaying plant litter. However, the current method of measuring bacterial biomass, flow cytometry, drastically underestimates the bacterial biomass levels associated with litter samples. To determine and correct for this underestimation, the present study determined conversion factors using direct counting methods via epifluorescence microscopy. These conversion factors were then applied to flow cytometry counts for seven different studies. The studies analyzed the effects of light and other covarying factors on the bacterial biomass associated with various samples of leaf …


Antibiotic Resistant Bacteria, Antibiotic Resistance Genes And Potential Drivers In The Aquatic Environments, Shuo Shen 2020 The University of Southern Mississippi

Antibiotic Resistant Bacteria, Antibiotic Resistance Genes And Potential Drivers In The Aquatic Environments, Shuo Shen

Dissertations

As antibiotic resistance genes in aquatic environment have been increasing across the world, affecting water quality and public health, many studies documented concentrations of antibiotic resistance genes and some studies discussed their potential drivers. However, systematic and quantitative reviews that link antibiotic resistance genes (ARGs) to anthropogenic and environmental factors are limited. Nevertheless, this information will be important for developing regulation policy on controlling antibiotic use and therefore reducing potential risks to antibiotic resistance. I conducted meta-analysis of ARGs concentration at a global scale using Bayesian inference to explore climatic and socio-economic factors as drivers. I found local-scale climatic variables …


The Effects Of Farnesol, A Quorum Sensing Molecule From Candida Albicans, On Alcaligenes Faecalis, Savannah Hutson 2020 East Tennessee State University

The Effects Of Farnesol, A Quorum Sensing Molecule From Candida Albicans, On Alcaligenes Faecalis, Savannah Hutson

Undergraduate Honors Theses

Quorum sensing molecules have become a recent focus of study to learn if and how they can be used, both on their own and in conjecture with current antimicrobial methods, as a means of bacterial control. One such quorum sensing molecule is the sesquiterpene alcohol, Farnesol, which is synthesized and released by the fungus, Candida albicans. In most in-vivo cases, our laboratory has shown that Alcaligenes faecalis overtakes C. albicans, preventing its growth. However, as a way to counteract this inhibitory effect, Farnesol may be one way that Candida has found to fight back. In this study, we …


Second Messenger Cyclic-Di-Gmp Regulation In Acinetobacter Baumannii, Justin Deal 2020 East Tennessee State University

Second Messenger Cyclic-Di-Gmp Regulation In Acinetobacter Baumannii, Justin Deal

Undergraduate Honors Theses

Over time, “superbugs,” or bacteria that have become resistant to antibiotics, have become a great concern in modern medicine. Viable alternates are currently being looked into as effective and safe ways to prevent or treat infections caused by these superbugs. One such method is through the utilization of the second messenger molecule cyclic-di-GMP (c-di-GMP) that has been shown to regulate phenotypes within other bacteria that may control surface colonization in Acinetobacter baumannii. Through a series of experiments, the active enzymes that create c-di-GMP - diguanylate cyclases - and break down c-di- GMP - phosphodiesterases - have been inactivated in …


Characterization Of The Broad-Spectrum Inhibitory Capability Of Alcaligenes Faecalis And A. Viscolactis Against Potential Pathogenic Microorganisms, Andrew Fuqua 2020 East Tennessee State University

Characterization Of The Broad-Spectrum Inhibitory Capability Of Alcaligenes Faecalis And A. Viscolactis Against Potential Pathogenic Microorganisms, Andrew Fuqua

Undergraduate Honors Theses

The recent rise of multidrug resistant microorganisms has grown from an isolated concern to a massive public health crisis. It has become imperative that scientists look for new ways to combat this issue. Due to the selective pressures of competition, bacteria and other microbes possess a host of defenses and weapons designed to exploit vulnerabilities in other microorganisms. Consequently, the study of these systems and microbial interactions has much to reveal in the search for novel antimicrobial treatments. Previous research from our laboratory has discovered that both Alcaligenes faecalis and Alcaligenes viscolactis, two rarely studied and generally non-virulent bacteria, …


Gut Pathophysiology In Mouse Models Of Social Behavior Deficits, Kyla Scott 2020 East Tennessee State University

Gut Pathophysiology In Mouse Models Of Social Behavior Deficits, Kyla Scott

Undergraduate Honors Theses

Autism spectrum disorders (ASD) encompass neurodevelopment disorders characterized by atypical patterns of development that impact multiple areas of functioning beginning in early childhood. The etiology of ASD is unknown and there are currently no preventative treatment options. Gastrointestinal symptoms are commonly associated comorbidities. The microbiota-gut-brain axis is a multidirectional communication chain that connects the central and enteric nervous system that relates brain function to peripheral intestinal functions. Changes within this axis have been postulated in ASD. For example, the “leaky gut theory” proposes that chronic inflammation is linked to alterations in the bacterial profiles of the gut microbiome and subsequent …


A Study Of The Polymicrobial Inhibitory Interactions Between Alcaligenes Faecalis And Staphylococcus Aureus, Blakeley Griffin 2020 East Tennessee State University

A Study Of The Polymicrobial Inhibitory Interactions Between Alcaligenes Faecalis And Staphylococcus Aureus, Blakeley Griffin

Undergraduate Honors Theses

Members of the Staphylococcus genus are found as a part of normal microflora in humans and can commonly be found on the skin or in the nasal cavity. However, these microorganisms can cause serious and life-threatening opportunistic infections when there is a break in the physical barrier of skin. These infections have become difficult to treat as resistant strains emerge, particularly Methicillin Resistant Staphylococcus aureus (MRSA). MRSA has become a commonly acquired nosocomial infection which is difficult to treat with conventional antibiotics of the blactam class. Even Vancomycin, a last resort antibiotic, has been ineffective on some infections. Furthermore, …


Assessing The Influence Of Riparian Invasion By The Shrub Lonicera Maackii On Terrestrial Subsidies To Headwater Streams, Erin C. Rowekamp, Julia I. Chapman, Ryan McEwan 2020 University of Dayton

Assessing The Influence Of Riparian Invasion By The Shrub Lonicera Maackii On Terrestrial Subsidies To Headwater Streams, Erin C. Rowekamp, Julia I. Chapman, Ryan Mcewan

Biology Faculty Publications

Invasion of Amur honeysuckle (Lonicera maackii) into riparian areas of headwater streams creates strong potential for alterations of terrestrial subsidies that may drive bottom-up effects on aquatic biota. In this study, we analyzed effects of L. maackii on terrestrial subsidies in stream sites that represented a gradient of invasion intensity in temperate deciduous forests of southwestern Ohio (USA). Leaf litter biomass, terrestrial and aquatic fine woody debris (0.5–9.9 cm diameter) volume and count, and terrestrial and aquatic coarse woody debris (>9.9 cm diameter) volume were analyzed. Based on previous research, we hypothesized that sites with a higher …


A Putative Cystathionine Beta-Synthase Homolog Of Mycolicibacterium Smegmatis Is Involved In De Novo Cysteine Biosynthesis, Saroj Kumar Mahato 2020 University of Arkansas, Fayetteville

A Putative Cystathionine Beta-Synthase Homolog Of Mycolicibacterium Smegmatis Is Involved In De Novo Cysteine Biosynthesis, Saroj Kumar Mahato

Graduate Theses and Dissertations

Mycobacteria include serious pathogens of humans and animals. Mycolicibacterium smegmatis is a non-pathogenic model that is widely used to study core mycobacterial metabolism. This thesis explores mycobacterial pathways of cysteine biosynthesis by generating and study of genetic mutants of M. smegmatis. Published in vitro biochemical studies had revealed three independent routes to cysteine synthesis in mycobacteria involving separate homologs of cysteine synthase, namely CysK1, CysK2, and CysM. However, in vivo data were lacking. The M. smegmatis genome encodes only a CysM homolog and lacks orthologs for CysK1 or CysK2. The gene that codes for CysM is a part of an …


Development Of An Attenuated Zika Virus By Editing The 5’ Untranslated Region, E. Ashley Thompson 2020 The University of Southern Mississippi

Development Of An Attenuated Zika Virus By Editing The 5’ Untranslated Region, E. Ashley Thompson

Master's Theses

Zika Virus (ZIKV) is a mosquito-transmitted flavivirus that usually causes no symptoms to mild febrile in humans, and it has been regarded as an insignificant pathogen to public health. However, recent outbreaks of ZIKV infection have revealed that ZIKV can cause severe neurological effects in adults, such as Guillain-Barre Syndrome (GBS), and in infants whose mothers acquired the virus during pregnancy, causing Congenital Zika Syndrome (CZS). Currently, no approved vaccine is available and there is a critical need to develop an effective and safe vaccine. While most vaccine developmental strategies target the viral prM-E protein of ZIKV, we aimed to …


Phospholipid Remodeling Via Exogenous Polyunsaturated Fatty Acid Uptake Modulates Stress Resistance In Vibrio Cholerae, William Strike 2020 University of Tennessee at Chattanooga

Phospholipid Remodeling Via Exogenous Polyunsaturated Fatty Acid Uptake Modulates Stress Resistance In Vibrio Cholerae, William Strike

Honors Theses

Antibiotic-resistant pathogens represent an escalating threat to public health worldwide, substantially increasing the burden of healthcare and community-acquired infections. Several factors contribute to the emergence and spread of this threat, including but not limited to improper antibiotic use and prescriptions in health-care settings and the community, increasing global travel and migration from countries that have higher levels of antibiotic-resistant pathogens, and a lack of new antibiotics under development. According to the World Health Organization, rising rates of resistance among Gram-negative bacteria (such as Vibrio cholerae) are of particular concern. These bacteria have evolved a number of endogenous membrane remodeling strategies …


Regulation Of Weak Acid-Dependent Cell Death By The Msaabcr Operon During Biofilm Formation Of Staphylococcus Aureus, Sarah-Elizabeth M. Polley 2020 The University of Southern Mississippi

Regulation Of Weak Acid-Dependent Cell Death By The Msaabcr Operon During Biofilm Formation Of Staphylococcus Aureus, Sarah-Elizabeth M. Polley

Honors Theses

Staphylococcus aureus is a dangerous human pathogen and a leading cause of both nosocomial and community-associated infections. Infection by S. aureus is a growing health concern due to the emergence of antibiotic resistance and the capability to form robust biofilms. Major constituents of the biofilm extracellular matrix are demonstrated to be released via controlled autolysis of a subpopulation of the biofilm. As indicated in past studies, the programmed cell death (PCD) of S. aureus grown in a biofilm microenvironment is potentiated by the buildup of acetate, a byproduct of glucose metabolism, which causes cytoplasmic acidification. Furthermore, it has been shown …


Toxicity Analysis Of 2’-Deoxyguanosine-N2-6-Aminopyrene And 2’-Deoxyguanosine-N2-8-Aminopyrene In Escherichia Coli, Emily Janeiro 2020 University of Connecticut

Toxicity Analysis Of 2’-Deoxyguanosine-N2-6-Aminopyrene And 2’-Deoxyguanosine-N2-8-Aminopyrene In Escherichia Coli, Emily Janeiro

Honors Scholar Theses

Cancer is a disease that stems from genomic errors that are not corrected properly by cellular repair mechanisms. Errors are more likely to form when organisms are subjected to DNA damage by mutagenic compounds. 1-Nitropyrene, a nitrated polycyclic aromatic hydrocarbon (nitro-PAH), has been shown to be a potent mutagen that causes cancer. Nitro-PAHs can arise from diesel exhaust products in the environment. Out of all nitro-PAHs, 1-nitropyrene is found in largest quantities in the environment. This poses a great need to study its effects biochemically in order to address its toxicity in DNA. Other nitropyrene derivatives, including 1,6-dinitropyrene and 1,8-dinitropyrene, …


Identification And Analysis Of Feather Degrading Bacteria: A Search For Keratinase Genes, Nehal Navali 2020 University of Connecticut

Identification And Analysis Of Feather Degrading Bacteria: A Search For Keratinase Genes, Nehal Navali

Honors Scholar Theses

Over two million tons of feather waste is generated annually by the poultry industry, the majority of which goes into landfills due to the difficulty of degrading its major component keratin. Although a portion of feather waste is eliminated via incineration or chemical treatment, the use of Feather Degrading Bacteria (FDB) has been proposed as a cheap and eco-friendly alternative. FDBs have been consistently isolated from the feather microbiome of birds and contain genes coding for the specialized protein keratinase which is able to degrade feathers. By doing so, feather waste, which is rich in nutrients, can be repurposed as …


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