Microbiology Commons^™

Impact Of Cadmium Stress On Soil Virus Reproduction And The Persistence Of Viruses Under Abiotic Conditions, Zhibo Cheng

Doctoral Dissertations

Soil viruses are ubiquitous and greatly impact the structure and function of soil microbial communities, with their effects modulated by various environmental factors. This study investigates the inactivation of naturally occurring soil viruses in sterilized soil, as well as the effects of cadmium (Cd) exposure and carbon (C) and nitrogen (N) nutrient availability on the population dynamics of virus-host communities in agricultural soil.

Lab-scale slurry and unsaturated experiments were performed to examine virus inactivation in the absence of host bacteria in sterilized soil. In slurry experiments, virus abundance declined by over 90% after 10 days of incubation. The addition of …

Detection And Control Of Environmentally Transmissible Viruses, Anand R. Soorneedi

Doctoral Dissertations

Viruses, owing to their ubiquitous nature and ability to infect almost every other species, have long been a subject of interest for scientists. Some of the virus species can be very deadly to humans and animals alike and can impose a huge economic and health burden across the world. The recent CoVID-19 pandemic underscores the importance of timely detection for developing effective intervention strategies. Unfortunately, some of the virus species that cause significant health and economic impacts do not have robust and reliable detection methods due to several reasons. In some cases, despite having gold standard methods for detection of …

Disinfectant Efficacy Against Sars-Cov-2 Surrogates, Bovine Coronavirus And Human Coronavirus Oc43, On Hard And Soft Non-Porous Surfaces, Breanna Kimbrell

All Theses

The novel human coronavirus (HCoV), severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged from Wuhan, China in the latter part of 2019. The rapid spread of SARS-CoV-2 amid the most recent COVID-19 pandemic forced countless foodservice establishments (FSEs) across the United States to close, taking a tremendous toll on the foodservice industry. Although primarily transmitted person-to-person, previous studies indicate that the duration of SARS-CoV-2 survival on different environmental surfaces provides adequate time for secondary transmission to occur. To prevent the further spread of SARS-CoV-2, effective disinfection of surfaces in FSEs is necessary. While disinfectants approved for use against SARS-CoV-2 are …

Early-Phase Drive To The Precursor Pool: Chloroviruses Dive Into The Deep End Of Nucleotide Metabolism, David Dunigan, Irina Agarkova, Ahmed Esmael, Sophie Alvarez, James L. Van Etten

Nebraska Center for Virology: Faculty Publications

Viruses face many challenges on their road to successful replication, and they meet those challenges by reprogramming the intracellular environment. Two major issues challenging Paramecium bursaria chlorella virus 1 (PBCV-1, genus Chlorovirus, family Phycodnaviridae) at the level of DNA replication are (i) the host cell has a DNA G+C content of 66%, while the virus is 40%; and (ii) the initial quantity of DNA in the haploid host cell is approximately 50 fg, yet the virus will make approximately 350 fg of DNA within hours of infection to produce approximately 1000 virions per cell. Thus, the quality and quantity of …

Vircy-Seq : A Protocol For Characterizing Viral Activity, Tyler James Dion

Legacy Theses & Dissertations (2009 - 2024)

The main purpose of pharmaceutical production is to produce safe effective medicine for patient use. In an effort to ensure patient safety constant surveillance for viruses takes place. The detection of a viral nucleic acid in a pharmaceutical production setting results in investigations to assess its infectious potential. This is an intensive, expensive process that entails many tests such as the observation of hemadsorption, cytopathic effects (CPE), and more. These tests are typically specific and only capture certain viruses, as factors like CPE can only be observed in some viral species. A new investigational method that is effective on all …

Neural Stem Cells: Age-Dependent Outcomes During Viral Infections In The Central Nervous System, Manisha N. Chandwani

Electronic Theses and Dissertations

Viral infections in the central nervous system (CNS) are associated with neurodevelopmental and neurobehavioral deficits. The outcomes of viral infections can be driven by damage and death of neurons. Neural stem cells (NSCs) play key roles in neurodevelopment, repair, and physiological brain function. During a viral infection, NSC activity can disturbed by direct infection of NSCs by the virus or by anti-viral immune response. Here, we aimed to assess whether the anti-viral immune response can impact NSC activity during an immunocompetent response in the adult brain. We utilized a transgenic mouse model of Measles virus infection where only the CNS …

An Investigation Of The Novel Use Of Bacteriophages To Diagnose And Treat Johne's Disease In Cattle, Max Kevane-Campbell

ORBioM (Open Research BioSciences Meeting)

Johne’s disease is a scourge to dairy farmers all over the world. It is an infectious disease that causes chronic inflammation and lesions along the inside of the small intestine of, primarily, ruminant animals (i.e., cattle and sheep). It is an incurable disease and urgently requires new and radical intervention strategies. Apart from careful on-site farm management practices, little can be offered to farmers to reduce the risk of infection, and nothing short of livestock culling is effective once an animal becomes infected. Currently, there are no vaccines licensed in Ireland or antibiotic treatment strategies available for Johne’s disease. This …

Diversity Of Bacteriophage In Burkholderia Species, Abigail Price

Honors Projects

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

Polerovirus Genomic Variation And Mechanisms Of Silencing Suppression By P0 Protein, Natalie Holste

School of Biological Sciences: Dissertations, Theses, and Student Research

The family Luteoviridae consists of three genera: Luteovirus, Enamovirus, and Polerovirus. The genus Polerovirus contains 32 virus species. All are transmitted by aphids and can infect a wide variety of crops from cereals and wheat to cucurbits and peppers. However, little is known about how this wide range of hosts and vectors developed. In poleroviruses, aphid transmission and virion formation is mediated by the coat protein read-through domain (CPRT) while silencing suppression and phloem limitation is mediated by Protein 0 (P0)—a protein unique to poleroviruses. P0 gives poleroviruses a great advantage amongst plant viruses and diversifies polerovirus species, but the …

Innovative Approaches In The Discovery Of Aquatic Mycobacteriophages, Janis H. Doss

Biomedical Sciences Theses & Dissertations

Bacteriophages (phages), viruses that infect bacteria, have many applications in medicine, agriculture, molecular biology, and other fields. As antibiotic resistance becomes an increasing problem, interest in phages has grown. The traditional techniques of phage discovery are successful for some phages, but others require modified procedures to achieve detectable host infection.

Mycobacterium is a diverse bacterial genus characterized by a unique cell wall containing mycolic acids, which aids in survival and pathogenesis. The aims of the present research were to isolate mycobacteriophages, use bioinformatics techniques to analyze mycobacterial prophages, and combine genetic analysis with multi-well plate host range studies to identify …

Repression Of Tick Microrna-133 Induces Organic Anion Transporting Polypeptide Expression Critical For Anaplasma Phagocytophilumsurvival In The Vector And Transmission To The Vertebrate Host, Ellango Ramasamy, Vikas Taank, John F. Anderson, Hameeda Sultana, Girish Neelakanta

Biological Sciences Faculty Publications

The microRNAs (miRNAs) are important regulators of gene expression. In this study, we provide evidence for the first time to show that rickettsial pathogen Anaplasma phagocytophilum infection results in the down-regulation of tick microRNA-133 (miR-133), to induce Ixodes scapularis organic anion transporting polypeptide (isoatp4056) gene expression critical for this bacterial survival in the vector and for its transmission to the vertebrate host. Transfection studies with recombinant constructs containing transcriptional fusions confirmed binding of miR-133 to isoatp4056 mRNA. Treatment with miR-133 inhibitor resulted in increased bacterial burden and isoatp4056 expression in ticks and tick cells. In contrast, treatment with …

Lysogeny And Use Of Mycobacteriophage Pita2, Eleanor Behling, Neocles B. Leontis, Jill Zeilstra-Ryalls

Honors Projects

The CDC has classified antibiotic resistance as the biggest health challenge of our era; every year 2 million lives are impacted and even lost due to resistant bacteria. Bacteriophages provide an alternative route to fighting infections that does not further the development of antibiotic resistance among bacterial species. A bacteriophage replicates inside a bacterial cell and then causes that cell to lyse, an event that kills the bacterial host. However, some phage can integrate their genomes into the host chromosome without causing lysis. The HHMI SEA-PHAGES program has generated a collection of bacteriophage that infect Actinobacteria species. Over 13,000 phages …

Mechanisms Of Silencing Suppression By A Polerovirus P0 Protein, Natalie Holste, Hernan Garcia-Ruiz

School of Biological Sciences: Posters and Presentations

Maize lethal necrosis is an intense viral disease spreading across sub-Saharan Africa. Maize is the staple crop grown in sub-Saharan Africa, but most crops infected with maize lethal necrosis will not survive to harvest. This causes immense economic hardship and starvation within the population. Maize lethal necrosis consists of a combination of two viruses, Maize chlorotic mottle virus (MCMV) and a virus from the genus potyvirus. In a recent study, a Maize yellow dwarf virus-RMV (MYDV-RMV)-like polerovirus, was repeatedly detected in plants with maize lethal necrosis. Poleroviruses have a silencing suppressor, P0 protein, and the mechanism of suppression is poorly …

Membrane Microdomains As Platforms For Extra-Cellular Fusions, Michael Hantak

Dissertations

Life requires biological membranes. Membrane-enclosed compartments separate and unite through dynamic fission and fusion reactions. These are catalyzed processes that are central in organismal biogenesis. This dissertation focuses on extracellular membrane fusions, which are central to several processes. (1) Enveloped viruses enter cells through membrane fusions. (2) Extracellular vesicles (EVs) also deliver molecules into cells through membrane fusions. (3) Entire cells also fuse together, generating fertilized zygotes, skeletal muscles, and giant cell macrophages.Mechanisms of extracellular membrane fusion are poorly understood. This dissertation aimed to further define these mechanisms. We focused on regulatory cofactors, including tetraspanins, transmembrane proteins that cluster into …

A Recombinant Virus And Reporter Mouse System To Study Chronic Chikungunya Virus Pathogenesis, Alissa Roxanne Young

Arts & Sciences Electronic Theses and Dissertations

Chikungunya virus (CHIKV) is an arthritogenic alphavirus that during acute disease causes fever as well as severe joint and muscle pain. Chronic joint and muscle pain persists in a significant subset of patients, yet we still have a poor understanding of what drives this chronic disease. While replicating virus has not been detected in the joints of patients with chronic arthritis or in various animal models at chronic time points, persistent viral RNA can be detected for months after acute infection.

To identify the cells that could be contributing to chronic CHIKV pathogenesis, we developed recombinant viruses that express Cre …

Viral Mhc Class I Evasion Affects Anti-Viral T Cell Development And Responses, Elvin James Lauron

Arts & Sciences Electronic Theses and Dissertations

Cytotoxic CD8+ T cells (CTLs) play a critical role in protective immunity against viruses, a fact underscored by the evolution of viral CTL evasion mechanisms. For instance, many viruses commonly target the major histocompatibility complex class I (MHCI) antigen presentation pathway to prevent CTLs from recognizing infected cells. A striking example of this is cowpox virus (CPXV), which interferes with MHCI antigen presentation through two distinct mechanisms. One mechanism of CPXV-mediated MHCI inhibition is to retain MHCI molecules in the endoplasmic reticulum (ER). The second mechanism is to prevent antigen peptide loading onto MHCI molecules. When combined these mechanisms result …

Grapevine Vein Clearing Virus: Epidemiological Patterns And Construction Of A Clone, Cory Von Keith

MSU Graduate Theses

Grapevine vein clearing virus (GVCV) is a recently discovered virus belonging to the Badnavirus genus. Characteristic to its name, the virus is associated with a disease where symptoms manifest as pronounced vein-clearing, resulting in severe berry deformation and vine decline in susceptible grape varieties. Sustainable production of wine is dependent on healthy plants. The associated disease is mainly found in Midwest vineyards. Attempts were made in this thesis to provide evidence of causality of the virus to the associated disease and to infer the historical path and migration pattern of GVCV. Conclusions and discussions will provide grape producers with the …

Bacteriophages As Beneficial Regulators Of The Mammalian Microbiome, Joseph W. Francis, Matthew Ingle, Todd Charles Wood

Proceedings of the International Conference on Creationism

Much of the research on viruses has concentrated on their disease causing ability. The creation model biomatrix theory predicts that viruses play a beneficial role in cells and organisms. In this report we present a new theory which proposes that mammalian phages (bacteriophages), the most abundant organism associated with mammals, guard and regulate growth of the mammalian microbiome. We base this theory on nearly a century of published evidence that demonstrates that phage can insert into the bacterial genome and cover the surface of bacteria. We propose that this “cloaking” of the bacterial cell surface is an elegant mechanism whereby …

Honey Bee And Bumble Bee Antiviral Defense, Alexander J. Mcmenamin, Daughenbaugh F. Katie, Fenali Parek, Marie C. Pizzorno, Michelle L. Flenniken

Faculty Journal Articles

Bees are important plant pollinators in both natural and agricultural ecosystems. Managed and wild bees have experienced high average annual colony losses, population declines, and local extinctions in many geographic regions. Multiple factors, including virus infections, impact bee health and longevity. The majority of bee-infecting viruses are positive-sense single-stranded RNA viruses. Bee-infecting viruses often cause asymptomatic infections but may also cause paralysis, deformity or death. The severity of infection is governed by bee host immune responses and influenced by additional biotic and abiotic factors. Herein, we highlight studies that have contributed to the current understanding of antiviral defense in bees, …

Mechanism Of Virus Inactivation By Cold Atmospheric-Pressure Plasma And Plasma-Activated Water, Li Guo, Ruobing Xu, Lu Gou, Zhichao Liu, Yiming Zhao, Dingxin Liu, Lei Zhang, Hailan Chen, Michael G. Kong

Bioelectrics Publications

ABSTRACT Viruses cause serious pathogenic contamination that severely affects the environment and human health. Cold atmospheric-pressure plasma efficiently inactivates pathogenic bacteria; however, the mechanism of virus inactivation by plasma is not fully understood. In this study, surface plasma in argon mixed with 1% air and plasma-activated water was used to treat water containing bacteriophages. Both agents efficiently inactivated bacteriophages T4, ϕ174, and MS2 in a time-dependent manner. Prolonged storage had marginal effects on the antiviral activity of plasma-activated water. DNA and protein analysis revealed that the reactive species generated by plasma damaged both nucleic acids and proteins, consistent with the …

Enhancing The Sea-Phages App To Collect Weather-Related Metadata From Soil Sampling Locations, Kelly M. Degnon

Senior Honors Projects, 2010-2019

The bacteriophage population is extremely diverse and abundant, with a seemingly limitless number of phages that have yet to be isolated and sequenced. The SEA-PHAGES program discovers and completely sequences the genome of hundreds of phages every year, contributing to the ever-growing database of phage sequences. However, there is little data about the conditions in which these phages are collected and if weather conditions can have an effect on the likelihood of isolating a phage. The SEA-PHAGES app, when used by students in the SEA- PHAGES program, will collect data on the location and weather conditions in which a soil …

Transmembrane Domains Of Highly Pathogenic Viral Fusion Proteins Exhibit Trimeric Association In Vitro, Stacy R. Webb, Stacy E. Smith, Michael G. Fried, Rebecca Ellis Dutch

Molecular and Cellular Biochemistry Faculty Publications

Enveloped viruses require viral fusion proteins to promote fusion of the viral envelope with a target cell membrane. To drive fusion, these proteins undergo large conformational changes that must occur at the right place and at the right time. Understanding the elements which control the stability of the prefusion state and the initiation of conformational changes is key to understanding the function of these important proteins. The construction of mutations in the fusion protein transmembrane domains (TMDs) or the replacement of these domains with lipid anchors has implicated the TMD in the fusion process. However, the structural and molecular details …

Isolation Of A Mycobacterium Virus With The Infectivity Rate Tested At Various Temperatures, Katie Wegenast

Undergraduate Theses

Isolation techniques developed by the HHMI and the SEA-PHAGES program were used to obtain a bacteriophage from a mixture of loamy clay soil. The sample was retrieved from a forest edge in central Kentucky. The isolate produced large lytic plaques on a lawn of the bacterium Mycobacterium smegmatis. The bacteriophage was purified, amplified, and analyzed using restriction digest analysis with visualization by gel electrophoresis. Restriction digest analysis suggests the virus belongs to a group known as “A”. Mycobacteriophages are placed into distinct groups based on DNA sequences comparison. The next step in the procedure will be to document with …

Investigating The Infection And Persistence Of Sindbis Virus In Host Neurons, Gavin Schroter, Sally Hall, Monica Borucki

STAR Program Research Presentations

Sindbis virus, an Alphavirus in the Togaviridae family, is an enveloped, single-stranded positive-sense RNA virus. Found mostly in parts of Africa, Australia, Egypt, Philippines, and Northern Europe – it is known to cause Ockelbo or Pogosta disease [1]. This disease is characterized by the sudden onset of fever, headache, and arthralgia; followed by arthritis, rash, fatigue, and muscle pain. The symptoms are gone within 14 days, though cases have shown joint pain to last from 12 months to 2 and a half years [4]. Common to several other viruses, Sindbis is transmitted from birds (its reservoir) to humans via an …

Characterization Of Influenza Nucleoprotein Body Domain As Antiviral Target, Alicia Morgan Davis

Electronic Theses, Projects, and Dissertations

Influenza is a segmented negative strand RNA virus. Each RNA segment is encapsulated by viral nucleoprotein (NP) and bound by the viral RNA dependent RNA polymerase (RdRP) to form viral ribonucleoproteins (vRNPs) responsible for RNA synthesis. NP is a structural component of the vRNP but also interacts with both viral and host factors to regulate viral RNA expression. NP is conserved among influenza A isolates, making NP interactions compelling antiviral targets. Here I characterize mutations within 5 amino acids of NP that comprise an accessible region of the NP body domain, as determined by NP crystal structure. This region was …

Characterization Of Induced Rnai Silencing Of Vaccinia Virus Essential Genes, Kewa Jiang

University Scholar Projects

Vaccinia virus (VACV) is a large double-stranded DNA virus and the prototypical member of the family Poxviridae and is most notable for its use as the vaccine that eradicated smallpox (variola virus). More recently, VACV has been used to develop recombinant vaccines and immunotherapies. However, many of these processes require VACV replication to be tightly controlled. RNA interference (RNAi) is a powerful tool for in vitro silencing of mRNAs that are complimentary to 19-21 base pairs (bp) of double-stranded RNA (dsRNA). This project outlines the design and preliminary analysis of two inducible RNAi silencing constructs targeting multiple VACV essential genes …

Development And Characterization Of A Recombinant Orf Virus Vector Expressing The Spike Protein Of Porcine Epidemic Diarrhea Virus, Kyle Hain

Electronic Theses and Dissertations

Orf virus (ORFV), the type member of the genus Parapoxvirus of the family Poxviridae, causes orf or cutaneous pustular dermatitis in sheep and goats. ORFV is a ubiquitous virus capable of re-infecting its hosts multiple times over time. ORFV causes a non-systemic, self-limiting disease which is usually restricted to the skin surrounding the virus entry sites. ORFV has evolved several immunomodulatory proteins (IMPs) that evade and/or modulate host immune responses to infection and contribute to virus virulence and disease pathogenesis. Given biological properties and unique immunomodula tor y properties, ORFV has gained significant attention in recent years for its …

The Effect Of Environmental Selection Pressure On The Rate Of Recombination To An Advantageous Receptor Mutation In Bovine Coronavirus, Gavin Schroter, Sally Hall, Mona Hwang, Monica Borucki

STAR Program Research Presentations

Bovine Coronavirus (BCoV) is an important analogue in understanding the effectiveness of zoonotic, single-stranded, positive sense RNA viruses. Many of the most recent viral outbreaks have been attributed to RNA viruses that have one, or more, animal reservoirs [1]. BCoV is such a great candidate for studying these types of viruses because they are from the family Coronaviridae, which also contains the viruses that cause severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS). The goal of this study was to observe changes in genetic makeup of the virus’ outer membrane Spike protein via recombination between two …

Host Species Restriction Of Middle East Respiratory Syndrome Coronavirus Through Its Receptor, Dipeptidyl Peptidase 4, Neeltje Van Doremalen, Kerri L. Miazgowicz, Shauna Milne-Price, Trenton Bushmaker, Shelly Robertson, Dana Scott, Joerg Kinne, Jason S. Mclellan

Dartmouth Scholarship

Middle East respiratory syndrome coronavirus (MERS-CoV) emerged in 2012. Recently, the MERS-CoV receptor dipeptidyl peptidase 4 (DPP4) was identified and the specific interaction of the receptor-binding domain (RBD) of MERS-CoV spike protein and DPP4 was determined by crystallography. Animal studies identified rhesus macaques but not hamsters, ferrets, or mice to be susceptible for MERS-CoV. Here, we investigated the role of DPP4 in this observed species tropism. Cell lines of human and nonhuman primate origin were permissive of MERS-CoV, whereas hamster, ferret, or mouse cell lines were not, despite the presence of DPP4. Expression of human DPP4 in nonsusceptible BHK and …

Biosorption Of Heavy Metals Onto The Surface Of Bacteriophage T4, Zheng Huan Tan

School of Biological Sciences: Dissertations, Theses, and Student Research

Biosorption of heavy metals by bacterial and eukaryotic cell surfaces and the subsequent transport in aqueous environments is well recognized. However, very little is known about the roles viruses play in biosorption. Viruses outnumber prokaryotes and eukaryotes in environmental systems. These organisms represent abundant nanoparticulate organic colloids with reactive surfaces. Here we conducted a series of experiments to assess the biosorption potential of Escherichia coli bacteriophage T4. Adsorption of a heavy metal, Zn²⁺, to the surface of phage T4 was tested in a series of purified phage/metal solutions (0 µM – 1000 µM at 23°C). The Langmuir isotherm …