Microbiology Commons^™

Herpes Simplex Virus Type 1 : Interactions With The Cellular Proteasome And Microrna Pathways, Daniel Joseph Munson

Legacy Theses & Dissertations (2009 - 2024)

Herpes Simplex Virus Type 1 (HSV-1) is a human pathogen that is estimated to have infected 60-80% of the population worldwide, causing oral lesions, encephalitis, and blindness. Infection results in life-long latency of the virus, with periods of reactivation and symptomatic disease. Early in infection, HSV-1 induces the formation of replication compartments and VICE (virus induced chaperone enriched) domains within the nucleus. Adjacent to VICE domains, we observed foci which contained Mss1, a cellular protein normally associated with the proteasome. Mss1 belongs to the AAA-ATPase family of proteins, which have been shown to function in DNA repair, transcription, translation, and …

Molecular Characterisation Of Soil Bacteria Degrading Pseudomonas Quinolone Signal., Ye Chen Soh

Student Works (2010-2019)

A different class of quorum sensing (QS) signal molecules, known as 2-alkyl-4- quinolones (AQs) have been discovered in Pseudomonas aeruginosa. The Pseudomonas Quinolone Signal (PQS) is arguably the most important QS signal in this signalling cascade, playing a vital role in regulating a myriad of virulence factors. A novel chemically defined medium with PQS as the sole carbon and energy source was developed and used in the successful enrichment and isolation of a PQS-degrading bacterium from rain forest soil samples. Based on 16S rDNA sequence analysis, the bacterium was classified as a strain of Achromobacter xylosoxidans. The PQS degradation activity …

Banf1 Is Required To Maintain The Self-Renewal Of Both Mouse And Human Embryonic Stem Cells, Jesse L. Cox, Sunil K. Mallanna, Briana D. Ormsbee, Michelle Desler, Matthew S. Wiebe, Angie Rizzino

Nebraska Center for Virology: Faculty Publications

Self-renewal is a complex biological process necessary for maintaining the pluripotency of embryonic stem cells (ESCs). Recent studies have used global proteomic techniques to identify proteins that associate with the master regulators Oct4, Nanog, and Sox2 in ESCs or in ESCs during the early stages of differentiation. Through an unbiased proteomic screen, Banf1 was identified as a Sox2- associated protein. Banf1 has been shown to be essential for worm and fly development but, until now, its role in mammalian development and ESCs has not been explored. In this study, we examined the effect of knocking down Banf1 on ESCs. We …

Analysis Of The Streptococcal Cpsa Protein In Dna-Binding And Regulation Of Capsule And Cell Wall Maintenance, Brett R. Hanson

Wayne State University Dissertations

The systemic pathogens Streptococcus agalactiae (GBS) and Streptococcus pneumoniae remain a significant threat to human health worldwide. The ability of these organisms to cause systemic disease is compounded by the production of a polysaccharide capsule that provides immune evasion function. The production of the polysaccharide capsule in systemic streptococcal pathogens is controlled in part by the membrane bound protein CpsA. These studies analyze the contribution of CpsA to regulation of capsule level in the model aquatic pathogen Streptococcus iniae and human specific pathogen GBS, and how this regulation affects virulence in in-vitro, ex-vivo, and in-vivo models of pathogenesis. We have …

Iron Oxide And Calcite Associated With Leptothrix Sp. Biofilms Within An Estavelle In The Upper Floridan Aquifer, Lee J. Florea, Chasity L. Stinson, Josh Brewer, Rick Fowler, B Joe Kearns, Anthony M. Greco

International Journal of Speleology

In Thornton’s Cave, an estavelle in west-central Florida, SEM, EDS, and XRD data reveal biofilms that are predominantly comprised of FeOOH-encrusted hollow sheaths that are overgrown and intercalated with calcite. Fragments of this crystalline biofilm adhere to the walls and ceiling as water levels vary within the cave. Those on the wall have a ‘cornflake’ appearance and those affixed to the ceiling hang as fibrous membranes. PCR of DNA in the active biofilm, combined with morphologic data from the tubes in SEM micrographs, point to Leptothrix sp., a common Fe-oxidizing bacteria, as the primary organism in the biofilm. Recent discoveries …

Efficacy Of The Pentavalent Rotavirus Vaccine, Rotateq (Rv5), Between Doses Of A 3-Dose Series And With Less Than 3 Doses (Incomplete Regimen), Penelope D. Dennehy, Timo Vesikari, David O. Matson, Robbin F. Itzler, Michael J. Dallas, Michelle G. Goveia, Mark J. Dinubile, Penny M. Heaton, Max Ciarlet

Community & Environmental Health Faculty Publications

Post-hoc analyses of the Rotavirus Efficacy and Safety Trial (RES T) were conducted to determine whether the pentavalent rotavirus vaccine (RV5) confers early protection against rotavirus gastroenteritis (RVGE) before completion of the 3-dose regimen. To evaluate the efficacy of RV5 between doses in reducing the rates of RVGE-related hospitalizations and emergency department (ED) visits in infants who ultimately received all 3 doses of RV5/placebo, events occurring from 2 weeks after the first and second doses to receipt of the subsequent dose (Analysis A) and events occurring from 2 weeks after the first and second doses to 2 weeks after the …

Surface Entropy Reduction To Increase The Crystallizability Of The Fab-Rna Complex, Priyadarshini Palaniandy Ravindran

Electronic Theses and Dissertations

Crystallizing RNA has been an imperative facet and a challenging task in the world of RNA research. Assistive methods such as Chaperone Assisted RNA Crystallography (CARC), employing monoclonal antibody fragments (Fabs) as crystallization chaperones have enabled us to obtain RNA crystal structures by increasing the crystal contacts and providing initial phasing information. Using this technology the crystal structure of [delta]C209 P4-P6 RNA (an independent folding domain of the self-splicing Tetrahymena group I intron) complexed to Fab2 (high affinity binding Fab) has been resolved to 1.95 Å (1). Although the complexed class I ligase ribozyme has also been crystallized using CARC …

Humboldt Journal Of Microbiology: Volume 13, Number 1- May 2011, Press Humboldt

Humboldt Journal of Microbiology

No abstract provided.

Microbial Ecology And Functional Genomics Of Deep-Water Coral-Associated Microbes, Julia Parker Galkiewicz

USF Tampa Graduate Theses and Dissertations

Lophelia pertusa is a cosmopolitan cold-water coral, often found in aphotic waters (>200m). Aggregations of L. pertusa (reefs) provide important habitat to many invertebrate and fish species and act as biodiversity hotspots in the deep sea. The health and diversity of these reefs is of vital importance to deep-sea ecosystems, and the microbial consortia associated with L. pertusa form the most basic ecological level. Deciphering the diversity and function of these microbes provides insight into the roles they play in maintaining reef health. This dissertation takes microbiological techniques that are used in shallow-water coral microbial research and applies them …

The Role Of Hiv-1 Proteins In Alzheimer's Disease Pathology, Brian Nelson Giunta

USF Tampa Graduate Theses and Dissertations

Prevalence of HIV-associated cognitive impairment is rising, the worst form of which is HIV-associated dementia (HAD). The disease is fuiled by a chronic innate type pro-inflammatory response in the brain which is highly dependent upon the activation of microglia. We first created an in vitro model of HAD composed of cultured microglial cells synergistically activated by the addition of IFN-gamma and the HIV-1 coat glycoprotein, gp120. This activation, as measured by TNF-alpha and NO release, is synergistically attenuated through the alpha7nAChR and p44/42 MAPK system by pretreatment with nicotine, and the cholinesterase inhibitor, galantamine. As these medications have been FDA …

Synthesis And Antimicrobial Activities Of S,S'-Heterosubstituted Disulfides, Praveen Ramaraju

USF Tampa Graduate Theses and Dissertations

Antibiotic resistance is a particularly critical health concern and has increased dramatically over the past two decades. For over a decade the Turos laboratory has been designing small molecules to target pathogenic microbes such as Staphylococcus aureus and the resistant variants like methicillin-resistant Staphylococcus aureus (MRSA). Previously, N-thiolated Β-lactams, N-thiolated 2-oxazolidinones and aromatic disulfides that were synthesized in Dr. Turos' lab have shown strong activity against these bacteria. The present work describes the synthesis and antimicrobial activities of a related structural class called S,S'-heterosubstituted disulfides. For ages, sulfur (elemental) has been used as an antibacterial for controlling infestation and bacterial …

Characterization Of Aminopeptidase Pepz In Staphylococcus Aureus Virulence, Tiffany Marie Robison

USF Tampa Graduate Theses and Dissertations

Staphylococcus aureus is a remarkably successful pathogen, accounting for an estimated 95,000 invasive infections annually in the U.S. alone. The burden of MRSA infections on public healthcare continues to rise, particularly with the continued spread of antibiotic resistant strains and the hyper-virulent CA-MRSA strains. The pathogenic nature of S. aureus can be attributed to the cache of virulence factors encoded within the genome of this organism. Typically, these are secreted toxins which directly interact with the host during infection, and facilitate pathogenesis. A previous screen in our laboratory investigating proteases in S. aureus identified a mutant in aminopeptidase Z as …

Sex And The Seas: Gene Transfer Agents, Elizabeth Young

USF Tampa Graduate Theses and Dissertations

Gene Transfer Agents (GTAs) are phage-like pthesiss that are produced by many alpha proteobacteria in late stationary growth phase and are capable of transferring chromosomal genes (termed "constitutive transduction"). Examination of alpha proteobacterial genomic sequences indicated widespread occurrence of GTA-like elements. The goal of this study was to investigate gene transfer potential of GTAs of marine alpha proteobacteria in culture as well as in natural marine environments. Another goal was to determine the potential of bacterial symbionts from zooxanthellae and coral to genetically transfer beneficial properties between symbionts. Ruegeria mobilis (ID 45A6) was isolated from cultures of the coral endosymbiotic …

Assessing The Relationship Of Monocytes With Primary And Secondary Dengue Infection Among Hospitalized Dengue Patients In Malaysia, 2010: A Cross-Sectional Study, Benjamin Glenn Klekamp

USF Tampa Graduate Theses and Dissertations

Dengue, a group of four similar viruses transmitted through the bite of a mosquito, is estimated to infect upwards of 100 million annually in over 100 nations throughout the global equatorial belt. Distribution of global dengue is highly skewed as Southeast Asian and Western Pacific regions endure 75% of the global dengue burden. Similar to other regional countries, Malaysia has been rapidly urbanizing, which has supported a hyperendemic dengue state.

The biological pathway by which dengue infection causes a wide range of clinical manifestations, spanning asymptomatic to life-threatening severe complications, is not comprehensively understood. Historically, severe dengue complications have primarily …

Investigation Of The Optimal Dissolved Co2 Concentration And Ph Combination For The Growth Of Nitrifying Bacteria, Raymond Anthony Morris

USF Tampa Graduate Theses and Dissertations

Ammonium (NH₄⁺) is a biological nutrient that is transformed in a wastewater treatment plant (WWTP) in a process called activated sludge. This is accomplished in an aerobic environment using microorganisms and inorganic carbon that convert the ammonium to nitrate (NO₃^-). This process is termed nitrification. Removal of ammonium is necessary due to its oxygen demand and toxicity to the environment.

Nitrification is considered a slow process due to the slow growth rate of the nitrifying bacteria. Ammonia oxidizing bacteria (AOB) first covert the ammonium (NH₄⁺) to nitrite (NO₂^-) …

Microbial Landscapes Of Corals And Ctenophores, Camille Arian Daniels

USF Tampa Graduate Theses and Dissertations

As technology and engineering allow mankind to survey nature at finer scales, the importance of bacteria has been elucidated in their metabolic diversity, ability to transfer genetic information, involvement in biogeochemical cycling, and sheer abundance. With an individual domain of life unto themselves, this diverse group of microorganisms plays an integral role in facilitating life on land and in the oceans, and is second only to viruses in abundance on Earth. They carve niches in a wide range of environments, including those inhospitable to other life forms, and reside in concert or to the detriment of other microbes and/or hosts …

Development Of A Non-Invasive Electrode For Intradermal Electrically Mediated Dna Vaccination, Amy Lynn Donate

USF Tampa Graduate Theses and Dissertations

Current progress in the development of vaccines has decreased the incidence of fatal and non-fatal infections and increased longevity. However, new technologies need to be developed to combat an emerging generation of infectious diseases. DNA vaccination has been demonstrated to have great potential for use against a wide variety of diseases. Alone, this vaccine technology does not generate a significant immune response for vaccination, but combined with delivery by electroporation (EP), can enhance plasmid expression and immunity against the expressed antigen. Most EP systems, while effective, can be invasive and painful making them less desirable for use in vaccination. Our …

Pleiotropic Regulatory Function Of The Lysr Family Transcriptional Regulator Cpsy During Streptococcus Iniae Systemic Infection, Jonathan Paul Allen

Wayne State University Dissertations

The ability of a pathogen to metabolically adapt to the local environment for optimal expression of virulence determinants is a continued area of research. Orthologs of the Streptococcus iniae LysR family regulator CpsY have been shown to regulate methionine biosynthesis and uptake pathways, but appear to influence expression of several virulence genes as well. A S. iniae mutant with an in-frame deletion of cpsY is highly attenuated in a zebrafish infection model. The cpsY deletion mutant displays a methionine-independent growth defect in serum, which differs from the methionine-dependent defect observed for orthologous mutants of S. mutans and S. agalactiae. …

Characterisation Of Bacterial Extracellular Polysaccharides (Eps) And Other Complex Carbohydrates With Prebiotic Potential, Padraigin Murphy

Theses

Prebiotics are selectively fermented ingredient that allows specific changes, both in the composition and/or activity in the gastrointestinal microbiota that confers benefits upon host well-being and health’ It is not the prebiotic by itself but rather the changes induced in microflora composition that is responsible for its effects. Several sources of prebiotic were used in this study, namely extracellular polysaccharides (EPS) originating from Lactic Acid Bacteria (LAB), barley, oat. Laminaria digitata. Laminaria hyperborea and Saccharomyces cerevisiae. EPS-producing LAB were isolated from a wide variety of environmental and gastrointestinal niches. The strains were typed and classified according to their EPS-producing ability …

Enhanced Surveillance And Characterisation Of Three Significant Gram-Positive Pathogens, Annmarie Mollaghan

Theses

Clinical microbiology has been revolutionised in recent years by the introduction of molecular biology. Traditionally, the gold standard for diagnosis in the clinical microbiology laboratory has been culture, which in some cases, is gradually being replaced by molecular detection methods, particularly where the pathogen is difficult to grow or to identify, or when the significance of an organism is dependent on the detection of specific markers of pathogenicity, such as toxins. Many fastidious bacteria which are difficult to culture and present public health implications, i.e. Mycobacterium tuberculosis. Chlamydia trachomatis and Neisseria gonorrhoea, can now be detected using commercial molecular assays …

Hsv-1 Infection In Keratinocyte Cell Lines Treated With Mitotic Inhibitors, Asma A. Abbas

Browse all Theses and Dissertations

The hypothesis for this research was: Herpes simplex virus type 1 (HSV-1) infection of murine keratinocyte cell lines (HEL-30 and PAM-212) treated with mitotic inhibitors leads to silencing of virus replication. At 0.1 (Multiplicity of infection) MOI, PAM-212 keratinocytes showed some cell lysis and viral plaques were seen in HEL-30 keratinocyte cultures. PAM-212 keratinocytes, infected at 0.01 MOI, were more susceptible to the lytic effect of HSV-1 than were HEL-30 cells. In this study, 5-fluoro-2'-deoxyuridine (FUDR) treatment of both keratinocyte cell lines permitted an increase survival of HSV-1- infected keratinocytes especially for PAM-212 cell line which was further examined for …

Distribution Of Cellular Interferon Beta (Ifn-Β) In Murine Fibroblast Cell Lines Upon Infection Of Hsv-1, Rachael E. Curtis

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The hypothesis for this study was: IFN-β expression differs between murine fibroblasts (A2R1 and L929) of different mouse strains upon infection of HSV-1. Fluorescent microscopy was used to examine localization of IFN-β in the different murine fibroblast and keratinocyte cell lines after 6 hours of infection with herpes simplex virus type-1 (HSV-1). Because keratinocytes cell lines HEL-30 and PAM-212 grew in clusters, staining patterns in individual cells could not be determined. A notable difference in localization of IFN-β immune staining was seen between the two cell lines when infected with HSV-1. The A2R1 cell line showed perinuclear (PN) localization, while …

Targeted Knockdown Of Amp-Activated Protein Kinase Alpha 1 And Alpha 2 Catalytic Subunits, Larissa J. Tangeman

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AMP-activated protein kinase (AMPK) regulates cellular metabolism and promotes ATP production when energy is depleted. Evidence suggests that AMPK may be involved in oxygen sensing by carotid body cells, which are responsible for regulating the breathing rate to maintain proper blood oxygen levels. There are two isoforms of the catalytic alpha subunit, AMPKalpha1 and AMPKalpha2, which could be involved in oxygen sensing. Here, the production of a short hairpin RNA (shRNA) targeting both catalytic isoforms of AMPK in human, mouse, and rat is described. The shRNA causes significant knockdown of both isoforms of AMPK alpha in mouse and human cells …

Strategies For Long-Term Renal Allograft Survival In Iga Nephropathy Patients, Erin E. Lintz

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IgA nephropathy is one of the most common kidney diseases worldwide. Most IgA nephropathy patients will undergo a kidney transplant as a treatment. Treatment currently includes the use of immunosuppressants which are necessary to prevent graft rejection but present harmful side-effects when taken long-term. This review focuses on strategies which have the ability to promote tolerance of both donor and recipient cells within a transplant recipient. Such strategies allow development of mixed chimerism and thereby alleviate the need for long-term immunosuppressant usage in allograft recipients. These strategies could be applied to IgA nephropathy patients to allow kidney allograft acceptance without …

Amino Acid Substitutions Created In Reverse Transcriptase And Their Influence On Hiv-1 Mutation Frequencies, Amani Saud Alhejely

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As research has shown, a high mutation rate occurs during the reverse transcription RT process because HIV reverse transcriptase fails to correct erroneously incorporated nucleotides during the reverse transcription process. Based on various research articles, a series of amino acid substitutions created in RT were collected to find out their influence on virus mutation frequencies. Two tables were used; one for amino acid substitutions created in RT that increased the HIV-1 mutation rate and another for amino acid substitutions created in RT that decreased the HIV-1 mutation rate. The tables show which amino acid substitutions created in RT decreased or …

Developing A Quantitative Pcr Assay For Detecting Viral Vector Shedding From Animals, Swathee Chinnasamy

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Replication deficient viruses have been used widely for replacing, repairing, and deleting target genes. These recombinant viruses are tested on research animals or patients in clinical trials. Although viral vectors distribute in the body, they are also disseminated into the environment through secretion and excretion processes. By studying the extent of shedding, a proper risk assessment can be performed and appropriate biocontainment can be achieved. Adenoviral and lentiviral vectors were produced from commercially available kits. The transgene present in both vector systems was the lacZ reporter gene encoding for β-galactosidase. Primers and probes were designed for the encapsidation region of …

Detection Of Autoreactive Cd4 T Cells Using Major Histocompatibility Complex Class Ii Dextramers, Chandirasegaran Massilamany, Bijaya Upadhyaya, Arunakumar Gangaplara, Charles Kuszynski, Jay Reddy

Nebraska Center for Virology: Faculty Publications

Background: Tetramers are useful tools to enumerate the frequencies of antigen-specific T cells. However, unlike CD8 T cells, CD4 T cells - especially self-reactive cells - are challenging to detect with major histocompatibility complex (MHC) class II tetramers because of low frequencies and low affinities of their T cell receptors to MHCpeptide complexes. Here, we report the use of fluorescent multimers, designated MHC dextramers that contain a large number of peptide-MHC complexes per reagent.

Results: The utility of MHC dextramers was evaluated in three autoimmune disease models: 1) proteolipid protein (PLP) 139-151-induced experimental autoimmune encephalomyelitis in SJL/J (H-2 …

Kaposi Sarcoma-Associated Herpesvirus Degrades Cellular Toll-Interleukin-1 Receptor Domain-Containing Adaptor-Inducing Β-Interferon (Trif), Humera Ahmad, Rachel Gubbels, Florencia Meyer, Thomas Waterbury, Rongtuan Lin, Luwen Zhang

Nebraska Center for Virology: Faculty Publications

Kaposi sarcoma-associated herpesvirus (KSHV) is a human ƴ - herpesvirus associated with several human malignancies. The replication and transcription activator (RTA) is necessary and sufficient for the switch from KSHV latency to lytic replication. Toll-interleukin-1 receptor (TIR) domain-containing adaptorinducing β-interferon (TRIF, also called TIR-domain-containing adaptor molecule-1 (TICAM-1)) is a signaling adaptor molecule that is critically involved in the Toll-like receptor 3 (TLR-3) and TLR-4 signaling pathways for type I interferon (IFN) production, a key component of innate immunity against microbial infection. In this report, we find a new mechanism by which RTA blocks innate immunity by targeting cellular TRIF. RTA …

Human Papillomavirus 16 Variants From Zambian Women With Normal Pap Smears, Yan Jun Lei, Kgomotso Makhaola, Daraporn Pittayakhajonwut, Charles Wood, Peter C. Angeletti

Nebraska Center for Virology: Faculty Publications

Human papillomavirus (HPV) type 16 is the most prevalent high-risk viral genotype associated with cervical cancer. Six distinct phylogenetic clusters of HPVs have been identified and are distributed differently across five continents. HPV16 DNA was extracted from cervico-lavage samples from women with normal pap smears. The LCR regions were amplified in triplicate, cloned, sequenced, and analyzed from a total of 11 recovered HPV16 positive samples [Ng’andwe et al. (2007): BMC Infect Dis 7:77] were analyzed for sequence variation. The HPV16 LCR variants were assessed for promoter activity by use of a luciferase reporter gene. Six novel HPV16 variants with nucleotide …

Hiv-1 Clade B And C Isolates Exhibit Differential Replication: Relevance To Macrophage-Mediated Neurotoxicity, Agnes A. Constantino, Yunlong Huang, Hong Zhang, Charles Wood, Jialin C. Zheng

Nebraska Center for Virology: Faculty Publications

HIV-associated neurocognitive disorders (HAND) continue to be a consequence of HIV-1 infection among clade B-infected individuals. In contrast, the incidence of severe neurological impairment is lower among clade C-infected patients in regions of Sub-Saharan Africa and India. Biological aspects such as replication, cytopathicity, inflammatory response, and neurotoxicity unique to each clade influence neuropathogenicity and ultimately affect the clinical outcome of the disease. We hypothesize that productive infection by clade C isolates leads to macrophagemediated neurotoxicity, although to a lesser extent than clade B isolates. Using a panel of primary isolates of clades B and C we demonstrated that clade B …