Microbiology Commons^™

Mir146a-Mediated Targeting Of Fancm During Inflammation Compromises Genome Integrity, Devakumar Sundaravinayagam, Hye R. Kim, Ting T. Wu, Hyun H. Kim, Hyun-Seo Lee, Semo Jun, Jeong-Heon Cha, Younghoon Kee, Ho J. You, Jung-Hee Lee

Molecular Biosciences Faculty Publications

Inflammation is a potent inducer of tumorigenesis. Increased DNA damage or loss of genome integrity is thought to be one of the mechanisms linking inflammation and cancer development. It has been suggested that NF-κB-induced microRNA-146 (miR146a) may be a mediator of the inflammatory response. Based on our initial observation that miR146a overexpression strongly increases DNA damage, we investigated its potential role as a modulator of DNA repair. Here, we demonstrate that FANCM, a component in the Fanconi Anemia pathway, is a novel target of miR146a. miR146a suppressed FANCM expression by directly binding to the 3’ untranslated region of the gene. …

Adeno-Associated Virus-Vegf-165 Mediated Modification Of Adipose Derived Stem Cells For Cell Therapy, Upasana Niyogi

Browse all Theses and Dissertations

Chronic wounds have become a major clinical and economic burden in our society. New approaches that accelerate wound healing are desperately needed. Angiogenesis and vascularization play a critical role in healing. One of the essential angiogenic factors that promote the formation of vascular beds is vascular endothelial growth factor (VEGF). Moreover, adipose-derived stem cells (ASC), through their regeneration and differentiation properties, may promote healing when transplanted into a wound bed. I have proposed to develop a novel organotypic wound model to facilitate the study of wound healing process. I hypothesize that administration of genetically-modified ASC secreting VEGF via an adeno-associated …

Inactivation Of Acanthamoeba Spp. And Other Ocular Pathogens By Application Of Cold Atmospheric Gas Plasma, Wayne Heaselgrave, Gilbert Shama, Peter W. Andrew, Michael G. Kong

Bioelectrics Publications

Currently there are estimated to be approximately 3.7 million contact lens wearers in the United Kingdom and 39.2 million in North America. Contact lens wear is a major risk factor for developing an infection of the cornea known as keratitis due to poor lens hygiene practices. While there is an international standard for testing disinfection methods against bacteria and fungi (ISO 14729), no such guidelines exist for the protozoan Acanthamoeba, which causes a potentially blinding keratitis most commonly seen in contact lens wearers, and as a result, many commercially available disinfecting solutions show incomplete disinfection after 6 and 24 …

Investigation Of Anaplasma Phagocytophilum And Anaplasma Marginale Adhesin-Host Cell Interactions, Kathryn S. Hebert

Theses and Dissertations

Anaplasma phagocytophilum and A. marginale are the etiologic agents of bovine anaplasmosis and human granulocytic anaplasmosis, respectively. As obligate intracellular pathogens, binding and entry of host cells is a prerequisite for survival. The molecular events associated with these processes are poorly understood. Identifying the adhesins mediating binding, delineating their key functional domains, and determining the molecular determinants to which they bind not only benefits better understanding of Anaplasma spp. pathobiology, but could also benefit the development of novel approaches for protecting against infection. We previously demonstrated that A. phagocytophilum outer membrane protein A (ApOmpA) is critical for bacterial binding and …

The Endophytes Of Pediomelum Esculentum: A Unique Case In Legume Evolution, Tyrel Ryan Deutscher

Electronic Theses and Dissertations

Pediomelum esculentum (commonly prairie turnip) is a perennial legume of the Great Plains, consisting of a deep taproot and large edible tuber, and has served as a nutritious staple in Native American diets. The tuber is capable of storing up to 20 percent protein by weight. P. esculentum is a legume, but not a prominent nodule former; instead, it grows in nitrogen-limited soils and produces large amounts of protein. This suggests the involvement of biological nitrogen fixation. We have investigated the presence of diazotrophic endophytes in P. esculentum. Bacteria were isolated from wild plants on nitrogen free media, identified …

Synthetic Biology For Autotrophic And Heterotrophic Production Of Ethanol, Nathanael Braselton

Electronic Theses and Dissertations

Growing energy demand and rising levels of greenhouse gases has put massive strain on the global environment. Alternatives to fossil fuels are being developed in an attempt to curb climate change. Biotechnology has made large strides in order to create a completely renewable energy source by genetically modifying microbes to produce biofuels and other “green” high value compounds. In this thesis project, (1) E. coli ATCC9637 (E. coli W) was genetically modified to produce bioethanol from beet juice which contains mainly sucrose. The ethanol productivity by engineered E. coli W was 18.8 mg/L/H/OD₆₀₀.
(2) Cyanobacterium Anabaena sp. PCC7120 …

Role Of Silencing Rna Fgsir34 In Fusarium Graminearum's Pathogenicity To Wheat, Subha Dahal

Electronic Theses and Dissertations

Fusarium graminearum is an ascomycetous fungal pathogen that causes Fusarium head blight (FHB) disease in wheat and other cereal grains. Mycotoxin produced by the fungus, predominantly deoxynivalenol (DON), is considered as an important virulence factor for the spread of disease. Our previous study of a Dicer-like 2 knockdown mutant has led to our hypothesis that a silencing RNA, fgsiR34, might play a key role in regulating DON biosynthesis and some other virulent factors. To test this hypothesis, we generated an fgsiR34 over-expressing mutant (ΔfgsiR34+) using Inverse Repeat Transgene method and studied the pathogenicity of the mutant in …

Senescence Of Native Perennial Warm Season Grasses Senescence Associated Switchgrass Transcriptome, Michaellong Tran

Electronic Theses and Dissertations

Senescence of perennial crops enable continuous harvests after one sowing event. Perennials senesce at adapted rates of their native environments; however, early senescencing crops do not maximize the growing season as nutrient reallocation takes precedence. Chlorophyll degradation and nitrogen reallocation was observed to occur rapidly between mid to late September. Transcriptome analysis on early and late senescencing switchgrass cultivars reveals upregulation of starch metabolism, light reactions, Calvin-Benson Cycle, and anthocyanin synthesis in late senescencing switchgrass. Morphological variations between the two germplasms prolong the growing season of late senescencing switchgrass, maximizing yield. Expression of mRNA as senescence progresses and between the …

Colony Stimulating Factor-1 Receptor (Csf-1r) Expression, Degradation, And Signaling In Lipid-Laden Macrophages, Gregory Thompson

Electronic Theses and Dissertations

Atherosclerosis is a serious disease affecting a large portion of the world’s population. In atherosclerosis, macrophages become filled with lipid droplets and form fatty plaques in artery walls. The formation of these atherosclerotic plaques is dependent on the macrophage growth factor colony stimulating factor-1 (CSF-1); however, understanding the changes in CSF-1 signaling and related pathways in foam cells remain poorly investigated. Lipid-laden macrophages were formed through exposure of murine bone marrow derived macrophages to 100 μg/ml acetylated LDL for 24 h. Non-LDL treated macrophages were grown in parallel for each experiment and used for comparison. Immunofluorescent staining was used to …

The Roles Of Human Cytomegalovirus Tegument Proteins Pul48 And Pul103 During Lytic Infection, Daniel Angel Ortiz

Wayne State University Dissertations

THE ROLES OF HUMAN CYTOMEGALOVIRUS TEGUMENT PROTEINS pUL48 AND pUL103 DURING LYTIC INFECTION

by

DANIEL A. ORTIZ

December 2015

Advisor: Dr. Philip E. Pellett

Major: Immunology and Microbiology

Degree: Doctor of Philosophy

Human cytomegalovirus (HCMV) is a large double-stranded DNA virus that causes severe disease in newborns and immunocompromised patients. During infection, HCMV is able to reconfigure the host cell machinery to establish a virus producing factory, termed the cytoplasmic virion assembly complex (cVAC). Generating drugs that affect cVAC development or function provides an alternative mode of action for HCMV antivirals that can essentially eliminate virion production. The objective of …

Investigation Of A Ubiquitous Spore Surface Protein, Justyna Kordzikowska

Master's Theses

All bacterial spores are comprised of concentric shells. All spores are encased in a layer called the coat. Some spores have an additional layer outside of the coat called the exosporium. Presumably, this morphological variation is an adaptation to variation in the environments in which these species can be found. However, spores from species with and without exosporia can often be found in the same niche. We hypothesize, therefore, that spores with and without exosporia share a common surface protein. Bacillus anthracis possess a well characterized surface protein called BclA. A BclA homologue is also present on the surface of …

Isolation And Identification Of Bacterial Endosymbionts In The Brooding Brittle Star Amphipholis Squamata, Abbey Rose Tedford

Honors Theses and Capstones

Symbiotic associations with subcuticular bacteria (SCB) have been identified and studied in numerous echinoderms, including the SCB of the brooding brittle star, Amphipholis squamata. These SCB, however, have not been studied using current next generation sequencing technologies. Previous studies on the SCB of A. squamata placed these bacteria in the genus Vibrio (γ-Proteobacteria), but subsequent studies suggested that the SCB are primarily composed of α-Proteobacteria. The present study examines the taxonomic composition of SCB associated with A. squamata from the Northwest Atlantic. DNA was extracted using a CTAB protocol and 16S rRNA sequences were amplified …

The Characterization Of A Recombinant Virophage Integrase, Martin Christopher Chacon

Open Access Theses & Dissertations

Virophages are satellite-like dsDNA viruses that parasitize giant viruses of the family Mimiviridae. Mavirus is the second virophage discovered that associates with its host virus Cafeteria roenbergensis Virus (CroV). When co-infecting their common host cell Cafeteria roenbergensis, a marine zooplankton that is widely spread throughout the oceans, mavirus will inhibit CroV's replication. In addition, mavirus was shown to share high similarities to the Maverick/Polinton eukaryotic DNA transposons. A coding sequence in mavirus genome (MV02) reveals high homology to retroviral integrases such as those found in HIVs. The putative integrase MV02 is predicted to integrate mavirus DNA into the host genome. …

Lipoate Metabolism In Staphylococcus Aureus Pathogenesis, Maria Azul Zorzoli

Master's Theses

Lipoate is an essential cofactor of several proteins involved in cellular energy homeostasis and catabolism. Lipoate metabolism has been linked to pathogenesis in some microbial species, but its role in Staphylococcus aureus infections had not been explored. In this thesis, we tested the hypothesis that lipoate acquisition mechanisms promote S. aureus infectivity. We used a bacterial genetics approach to elucidate the biological function of the S. aureus genes involved in lipoate metabolism. Our findings allowed us to propose a model for lipoic acid de novo biosynthesis and salvage pathways in S. aureus. Moreover, we detail hitherto undescribed genetic arrangements of …

Antibody-Mediated Immunity To Vibrio Cholerae At Epithelial Surfaces, Kara Jeanette Levinson

Legacy Theses & Dissertations (2009 - 2024)

Vibrio cholerae, the causative agent of the severe diarrheal disease cholera, has an estimated worldwide disease burden in the millions and remains a significant public health threat. Immunity to V. cholerae is primarily antibody-mediated and though V. cholerae colonization evokes a mucosal immune response, it is the secretory IgA (SIgA) antibodies produced against bacterial surface antigens, specifically lipopolysaccharide (LPS) that confer protective immunity. SIgA antibodies are thought to function by inhibiting colonization by cross-linking and agglutination of pathogens, thereby limiting access to the epithelium, a process known as immune exclusion. Recent studies in other enteric pathogens have demonstrated that SIgA …

Recapitulating Cross-Species Transmission Of Sivcpz To Humans Using Humanized-Blt Mice, Zhe Yuan, Guobin Kang, Fangrui Ma, Wuxun Lu, Wenjin Fan, Christine M. Fennessey, Brandon F. Keele, Qingsheng Li

Nebraska Center for Virology: Faculty Publications

The origins of HIV-1 have been widely accepted to be the consequence of simian immunodeficiency viruses from wild chimpanzees (SIVcpz) crossing over to humans. However, there has not been any in vivo study of SIVcpz infection of humans. Also, it remains largely unknown why only specific SIVcpz strains have achieved cross-species transmission and what transmission risk might exist for those SIVcpz strains that have not been found to infect humans. Closing this knowledge gap is essential for better understanding cross-species transmission and predicting the likelihood of additional cross-species transmissions of SIV into humans. Here we show hu-BLT mice are susceptible …

High Glucose Induces Reactivation Of Latent Kaposi’S Sarcoma-Associated Herpesvirus, Fengchun Ye, Yan Zeng, Jingfeng Sha, Tiffany Jones, Kurt Kuhne, Charles Wood, Shou-Jiang Gao

Nebraska Center for Virology: Faculty Publications

High prevalence of Kaposi’s sarcoma (KS) is seen in diabetic patients. It is unknown if the physiological condition of diabetes contributes to KS development. We found elevated levels of viral lytic gene expression when Kaposi’s sarcoma-associated herpesvirus (KSHV) infected cells were cultured in high glucose medium. To demonstrate the association between high glucose and KSHV replication, we xeno29

grafted telomerase-immortalized human umbilical vein endothelial cells that are infected with KSHV (TIVE-KSHV) into hyperglycemic and normal nude mice. The injected cells expressed significantly higher levels of KSHV lytic genes in hyperglycemic mice than in normal mice. We further demonstrated that high …

Persistent Low-Level Replication Of Sivδnef Drives Maturation Of Antibody And Cd8 T Cell Responses To Induce Protective Immunity Against Vaginal Siv Infection, Sama Adnan, R. Keith Reeves, Jacqueline Gillis, Fay E. Wong, Yi Yu, Jeremy V. Camp, Qingsheng Li, Michelle Connole, Yuan Li, Michael Piatak Jr., Jeffrey D. Lifson, Wenjun Li, Brandon F. Keele, Pamela A. Kozlowski, Ronald C. Desrosiers, Ashley T. Haase, R. Paul Johnson

Nebraska Center for Virology: Faculty Publications

Defining the correlates of immune protection conferred by SIVΔnef, the most effective vaccine against SIV challenge, could enable the design of a protective vaccine against HIV infection. Here we provide a comprehensive assessment of immune responses that protect against SIV infection through detailed analyses of cellular and humoral immune responses in the blood and tissues of rhesus macaques vaccinated with SIVΔnef and then vaginally challenged with wild-type SIV. Despite the presence of robust cellular immune responses, animals at 5 weeks after vaccination displayed only transient viral suppression of challenge virus, whereas all macaques challenged at weeks 20 and 40 post-SIVΔnef …

Cooperation And Punishment In The Arbuscular Mycorrhizal Symbiosis: Implications For Resource Exchange & Biological Market Dynamics, Jerry A. Mensah

Electronic Theses and Dissertations

The arbuscular mycorrhizal (AM) symbiosis is arguably the world’s most abundant and important mutualism, and brings together the roots of the majority of land plants and AM fungi to great mutual advantage. The AM symbiosis can increase the uptake of nutrients, such as phosphorus (P) and nitrogen (N), and improves the abiotic and biotic stress resistance of the host plant. AM fungi have the potential to act as biofertilizers and bioprotectors in sustainable agriculture. However, despite its significance, the mechanisms that control the resource exchange between both partners in the arbuscular mycorrhizal symbiosis are largely unknown. The main aim of …

Enhancing The Industrial Potential Of Filamentous Cyanobacteria, Tylor J. Johnson

Electronic Theses and Dissertations

The objectives of this project were to improve the industrial potential of filamentous N2-fixing cyanobacteria by increasing its biofuel tolerance, and to evaluate the economic feasibility and environmental impacts of a theoretical, cyanobacteria-based biofuel production facility. To develop a method to quantify filamentous cyanobacteria in dilute culture media, a dual-stained fluorescence assay was evaluated. While the viable cell stain (SYTO® 9) was accurate, the non-viable cell stain (propidium iodide) also bound to viable cells. Additional non-viable cell stains were evaluated, but none were accurate at quantifying viability. Thus we concluded that the viable cell stain SYTO® 9 is a reliable …

Quorum Sensing In Acinetobacter: With Special Emphasis On Antibiotic Resistance, Biofilm Formation And Quorum Quenching, Bindu Subhadra, Man Hwan Oh, Chul Hee Choi

Faculty Publications - Biological Sciences

Acinetobacter is an important nosocomial, opportunistic human pathogen that is gradually gaining more attention as a major health threat worldwide. Quorum sensing (QS) is a cell-cell communication system in which specific signaling molecules called autoinducers accumulate in the medium as the population density grows and control various physiological processes including production of virulence factors, biofilm and development of antibiotic resistance. The complex QS machinery in Acinetobacter is mediated by a two-component system which is homologous to the typical LuxI/LuxR system found in Gram-negative bacteria. This cell signaling system comprises of a sensor protein that functions as autoinducer synthase and a …

The Expression Of Aryl Hydrocarbon Receptor In Raw 264.7 Macrophages In The Presence Of Socs1 Peptide And Socs3 Peptide Mimetic And Cells Infected With Hsv-1, Maher Salem Alwethaynani

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Macrophages play a crucial role for our immune system and protect our body from infection. Suppressor of cytokine signaling (SOCS) proteins negatively regulate cytokine receptor and TLRs. The aryl hydrocarbon receptor (AhR) also performs an important role in immunity. This study investigated the changes in expression of AhR in RAW 264.7 macrophage cells after the addition of SOCS1 and SOCS3 peptide mimetics and also examined AhR expression in RAW 264.7 macrophage cells before and after the addition of HSV-1 RAW 264.7 murine macrophage cell lines which are from male BALB/c mice were used in this study. The addition of the …

Molecular And Biochemical Signaling Underlying Arabidopsis-Bacterial/Virus/Fungal Interactions, Mohamed H. El-Shetehy

Theses and Dissertations--Plant Pathology

Systemic acquired resistance (SAR) is a form of inducible defense response triggered upon localized infection that confers broad-spectrum disease resistance against secondary infections. Several factors are known to regulate SAR and these include phenolic phytohormone salicylic acid (SA), phosphorylated sugar glycerol-3-phosphate (G3P), and dicarboxylic acid azelaic acid (AzA). This study evaluated a role for free radicals nitric oxide (NO) and reactive oxygen species (ROS) in SAR. Normal accumulation of both NO and ROS was required for normal SAR and mutations preventing NO/ROS accumulation and/or biosynthesis compromised SAR. A role for NO and ROS was further established using pharmacological approaches. Notably, …

Endosymbiotic Bacteria In The Bed Bug, Cimex Lectularius L. (Hemiptera: Cimicidae), Mark H. Goodman

Theses and Dissertations--Entomology

The return of bed bugs to prominence as an urban pest has precipitated an emphatic research response from the scientific community in an effort to better understand their biology and management. However, not all aspects of bed bug biology have received equal attention. The role of symbiotic bacteria in the normal function and biology of insects is often underappreciated, and this is true of bed bugs. Bed bugs have two main endosymbiotic bacteria, a Wolbachia species and a poorly-characterized gamma-proteobacterium referred to as BLS. However, their interactions with the host are poorly understood. I explored various aspects of these symbionts …

Attached Algae As An Indicator Of Water Quality: A Study Of The Viability Of Genomic Taxonomic Methods, Allison R. Wood

Honors Theses and Capstones

This research involved evaluating algae as an indicator of water quality in New Hampshire's rivers, with a focus on the Great Bay Estuary. The project had three main goals. First, determining whether or not algae would work as an indicator of water quality in the great bay ecosystem, an environment where tidal currents are strong and water composition is mixed. The second goal was to compare traditional microscopic methods of taxonomy with emerging genomic methods, increasing the economic viability of attached algae monitoring. The third project goal, still underway, is to evaluate massive amounts of genomic data from the Great …

Antibiotic Efficacy And Interaction In Escherichia Coli During Varying Nutrient Conditions, Kristina K. Millar

Scripps Senior Theses

Due to the recent rise in antibiotic resistant pathogens, and the difficulties surrounding the quest for new antibiotics, many researchers have started revisiting antibiotic interactions in hopes of finding new treatment options. The primary outcome of this project was to examine the efficacy of concomitant antibiotic use under varying nutrient conditions, to identify variations in antibiotic interactions. Antibiotic interactions were studied, utilizing E. coli as a model bacterial system, grown in four different media types. E. coli cultures were treated with streptomycin, tobramycin, erythromycin, and amikacin individually and in a pairwise fashion at varying doses. We found that at least …

Humboldt Journal Of Microbiology: Volume 18, Number 1- May 2016, Press Humboldt

Humboldt Journal of Microbiology

No abstract provided.

Synergistic Growth In Bacteria Depends On Substrate Complexity, Yi-Jie Deng, Shiao Y. Wang

Faculty Publications

Both positive and negative interactions among bacteria take place in the environment. We hypothesize that the complexity of the substrate affects the way bacteria interact with greater cooperation in the presence of recalcitrant substrate. We isolated lignocellulolytic bacteria from salt marsh detritus and compared the growth, metabolic activity and enzyme production of pure cultures to those of three-species mixed cultures in lignocellulose and glucose media. Synergistic growth was common in lignocellulose medium containing carboxyl methyl cellulose, xylan and lignin but absent in glucose medium. Bacterial synergism promoted metabolic activity in synergistic mixed cultures but not the maximal growth rate (μ). …

The Impact Of Oxygen On Bacterial Enteric Pathogens, Nathan Wallace, Ashley N. Zani, Elizabeth A. Abrams, Yvonne Sun

Biology Faculty Publications

Bacterial enteric pathogens are responsible for a tremendous amount of foodborne illnesses every year through the consumption of contaminated food products. During their transit from contaminated food sources to the host gastrointestinal tract, these pathogens are exposed and must adapt to fluctuating oxygen levels to successfully colonize the host and cause diseases. However, the majority of enteric infection research has been conducted under aerobic conditions. To raise awareness of the importance in understanding the impact of oxygen, or lack of oxygen, on enteric pathogenesis, we describe in this review the metabolic and physiological responses of nine bacterial enteric pathogens exposed …

Characterization Of Insertion Sequence Is605 In Halanaerobium Hydrogeniformans, Michael C. Sadler

Masters Theses

"Insertion sequences are the smallest prokaryotic transposable elements. These genes play a significant evolutionary role by promoting genome plasticity. Insertion sequences are highly diverse elements that have largely been uncharacterized. As such, the ability to accurately identify, annotate, and infer genomic impact of insertion sequences is lacking. The study of new insertion sequences contributes knowledge to their annotation and evolution. Halanaerobium hydrogeniformans is a unique organism with an abnormally high number of insertion sequences. A family of insertion sequences, IS200/605, showed several interesting distinctions from other elements in the genome, including severe open reading frame degradation, and was characterized in …