Microbiology Commons^™

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 …

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 …

Sulfate-Reducing Bacteria Community Analysis: Isco/Isb Coupled Remediation, Christopher K. Bartlett

Theses and Dissertations (Comprehensive)

Improved techniques for remediating groundwater systems are required for the more than 500,000 contaminated sites in North America. Many of these sites are the legacy of historical industrial operations, inappropriate disposal practices and accidental releases. The most widely observed contaminant at many of these sites is petroleum hydrocarbons (PHCs). Recently, remediation efforts that involve the sequential application of treatment technologies have gained widespread interest. One specific sequential technology application or treatment train employs the aggressive nature of a chemical oxidation followed by bioremediation for polishing. When persulfate is used as the chemical oxidant its natural degradation by-product is sulfate, an …

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 …

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 …

Flaviviruses As A Cause Of Undifferentiated Fever In Sindh Province, Pakistan: A Preliminary Report, Erum Khan, Joveria Q. Farooqi, Kelli L. Barr, Dhani Prakoso, Amna Nasir, Akbar Kanji, Sadia Shakoor, Faisal Riaz Malik, Rumina Hasan, John A. Lednicky

Department of Pathology and Laboratory Medicine

Arboviral diseases are expanding worldwide, yet global surveillance is often limited due to diplomatic and cultural barriers between nations. With human encroachment into new habitats, mosquito-borne viruses are also invading new areas. The actual prevalence of expanding arboviruses is unknown in Pakistan due to inappropriate diagnosis and poor testing for arboviral diseases. The primary objective of this study was to document evidence of flavivirus infections as the cause of undifferentiated fever in Pakistan. Through a cooperative effort between the USA and Pakistan, patient exposure to dengue virus (DENV), West Nile virus (WNV), and Japanese encephalitis virus (JEV) was examined in …

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

Browse all Theses and Dissertations

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 …

The Expression Of Major Histocompatibility Class I And Major Histocompatibility Class Ii On Macrophages In The Presence Of Aryl Hydrocarbon Antagonist (Ch-223191), Caitlin Wilson

Browse all Theses and Dissertations

Macrophages are crucial for ridding the body of debris and foreign cells. The aryl hydrocarbon receptor (AhR) also plays a critical role in immunity. This study examined the effect of the AhR on the expression of major histocompatiability complex class I (MHCI) and MHC class II (MHCII) in two murine macrophage cell lines. This study used Raw264.7 and J774A.1 murine macrophage cell lines. The Raw264.7 cells are from male BALB/c mice while the J774A.1 cells are from female BALB/cN mice. The addition of the AhR anatagonist CH-223191 (AhRa) showed that the AhR does not significantly impact MHCI expression. However, MHCII …

Anaplasma Marginale Actively Modulates Vacuolar Maturation During Intracellular Infection Of Its Tick Vector, Dermacentor Andersoni, Foregivemore Magunda, Chelsea Wright Thompson, David A. Schneider, Susan M. Noh

Biological Sciences Faculty Publications

ABSTRACT Tick-borne transmission of bacterial pathogens in the order Rickettsiales is responsible for diverse infectious diseases, many of them severe, in humans and animals. Transmission dynamics differ among these pathogens and are reflected in the pathogen-vector interaction. Anaplasma marginale has been shown to establish and maintain infectivity within Dermacentor spp. for weeks to months while escaping the complex network of vacuolar peptidases that are responsible for digestion ofthe tick blood meal. How this prolonged maintenance of infectivity in a potentially hostile environment is achieved has been unknown. Using the natural vector Dermacentor andersoni, we demonstrated that A. marginale …

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 …

Arbuscular Mycorrhizal Fungi Of Northern White Cedar (Thuja Occidentalis L.): Habitat Effects On Fungal Communities And Inoculum Effects On Plant Growth On Acid Peat Soils, Guswarni Anwar

Dissertations, Master's Theses and Master's Reports

The relationship of arbuscular mycorrhizal (AM) fungi with northern white cedar (NWC) was examined from the perspective of both fundamental questions about habitat specificity in the root fungal community, as well as applied questions regarding AM fungal efficacy in NWC restoration in peat soils. I performed two experiments testing the effects of AM fungi on survival, growth, and nutrition of NWC seedlings; and one molecular study to determine the habitat effects on community composition of NWC root-associated fungi. First, a greenhouse AM inoculation experiment was conducted in factorial combination with fertilization and liming to examine conditional effectiveness of AM fungal …

Inhibition Of Bacterial Growth And Prevention Of Bacterial Adhesion With Localized Nitric Oxide Delivery, Julia Osborne

Dissertations, Master's Theses and Master's Reports

Bacterial infections continue to be a problem at the site of an indwelling medical device, and over the years, various bacterial strains have become more resistant to current antibiotic treatments. Bacterial infection at an indwelling medical device can be dangerous and affect the performance of the medical device which can ultimately lead to the failure of the device due to bacterial resistance to treatment.

Nitric Oxide (NO) has been shown to possess antibacterial properties to prevent and inhibit bacterial growth. NO releasing coatings on indwelling medical devices could provide a reduction in bacterial infections that occur at the device site …

Atmospheric Cold Plasma Interactions With Modified Atmosphere Packaging Inducer Gases For Safe Food Preservation., Lu Han, Daniela Boehm, Vladimir Milosavljević, Ester Amias, Patrick J. Cullen, Paula Bourke

Articles

Diverse microbiological challenges and pervasive microbial resistance drive technological development in food processing, where increasing process complexity and consumer demand for less processed goods leads to strong demand for effective decontamination. Atmospheric cold plasma (ACP) has wide potential for decontamination application in the food sector. We investigated the effect of Modified Atmosphere Packaging (MAP) gas mixtures on reactive species generated, their efficacy and mechanism of inactivation against Escherichia coli, Listeria monocytogenes and Staphylococcus aureus. Oxygen levels in the applied working gas had positive interactive effects on ROS generation, in-package inactivation efficacy in conjunction with post-treatment storage time. …

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 …

Frequency And Etiology Of Community-Acquired Bloodstream Infection In Hospitalized Febrile Children, Tufail Soomro, Shiyam Sunder Tikmani, Sumera Aziz Ali

Community Health Sciences

Background: Blood stream infection is a serious problem that needs immediate attention and treatment. We aim to identify the frequency of common organisms in blood culture of febrile pediatric patients so that empirical antibiotic therapy can be started timely.
Methods: This cross-sectional study was conducted in pediatric ward Civil Hospital Sukkur from 1st May 2013 to 31st October 2014. Children of both genders who are between the age of one month to 15 years admitted to the pediatric ward with a fever of > 38.0 c and with a history of fever ˃ two days and whose blood culture has been …

Characterizing The Role Of The Fact Complex In Hiv-1 Infection, Angelica Patricia Lopez

Open Access Theses & Dissertations

The lens epithelium-derived growth factor p75 (LEDGF/p75) is a chromatin-bound protein essential for efficient lentiviral integration. Knockdown of this protein severely affects HIV-1 integration levels and thus itâ??s replication. Genome-wide studies have located LEDGF/p75 inside actively transcribed genes where it mediates lentiviral integration. Although this is clearly established, the molecular mechanisms of LEDGF/p75 in HIV-1 infection remain in part elusive.

Using protein-protein interaction assays, we demonstrated that LEDGF/p75 complexes with a chromatin remodeling complex, Facilitates Chromatin Transcription (FACT), a heterodimer of the structure specific recognition protein 1 (SSRP1) and the human homolog of suppressor of Ty 16 (hSpt16). The FACT …

Defining And Characterizing The Step In The Hiv-1 Viral Life Cycle Affected By Fullerene Derivatives, Zachary Sean Martinez

Open Access Theses & Dissertations

Fullerene derivatives, both C60 and C70, were synthesized and characterized to test their activity against HIV-1 infection. The derivatives tested have previously been reported to inhibit HIV-1 replication and/or in vitro activity of reverse transcriptase. It was found that viruses produced in the presence of low micromolar concentrations of most of these fullerene derivatives exhibit a reduction in viral infectivity greater than 99%. Quantification of virion-associated viral RNA and p24 indicates that RNA packaging and viral production were unremarkable in these viruses. These compounds did not affect infectivity of mature virions, indicating no effect on the early steps of the …

Determining The Role Of Poly [Adp-Ribose] Polymerase 1 (Parp-1) In Retroviral Infection, Luis Valdes Rodriguez

Open Access Theses & Dissertations

Possible links between PARP-1 and HIV-1 have been previously reported but the role of this protein during viral infection has remained elusive. Based on the high evolutionary conservation of PARP-1, from Drosophila to humans, we have been able to counteract the difficulties related with the functional redundancy manifested in the PARP family by studying the influence of PARP-1 on the expression of an endogenous retrovirus using the chicken B lymphoblastoid cell line DT40, this cell line exhibits low PARP-1 functional redundancy and is viable after PARP-1 knockout. We have determined that the transcription level of the endogenous retrovirus RAV-1 is …

Effects Of Epichloë Coenophiala−Tall Fescue Symbiosis On Plant-Microbe-Soil Interactions In A Temperate Pasture, Lindsey C. Slaughter

Theses and Dissertations--Plant and Soil Sciences

Plants interact in myriad ways with microorganisms to influence ecosystem processes such as nutrient cycling, which can regulate ecosystem response to global change. One important plant-microbe symbiosis occurs between cool-season grasses and asexual fungal Epichloë endophytes, such as tall fescue (Schedonorus arundinaceus) and Epichloë coenophiala. Because the common toxic strain of the endophyte (CTE) harms grazing livestock, non-livestock toxic endophyte (NTE) strains have been developed and are increasingly deployed in pastures. Little is known about how these symbioses impact other plant-microbe interactions and microbe-mediated soil processes in grassland ecosystems. I conducted three studies to determine how E. …

Screening For Pathogenic Escherichia Coli In The Chattahoochee River, Columbus, Georgia, Micah A. Staples

Theses and Dissertations

Escherichia coli testing is frequently used to indicate the possible presence of harmful pathogens, but E. coli itself can be pathogenic. Serotype 0157:H7, enterohemorrhagic E. coli, is likely the most medically important pathogenic strain of E. coli in the United States. In this study, we surveyed for 0157:H7 and three strains of another pathogenic subtype: enterotoxigenic E. coli. We isolated E. coli colonies from samples taken from the Chattahoochee River in Columbus, Georgia at two different locations, above and below wastewater outputs. We used PCR to test for the individual subtypes and then used a nested PCR protocol …