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Articles 1 - 11 of 11

Full-Text Articles in Microbiology

Iron Acquisition In Rhodococcus Erythropolis Strain Igts8: Characterization Of A Mutant Strain That Over Produces Siderophore., Melanie Anne Pratt Dec 2008

Iron Acquisition In Rhodococcus Erythropolis Strain Igts8: Characterization Of A Mutant Strain That Over Produces Siderophore., Melanie Anne Pratt

Electronic Theses and Dissertations

Iron is an essential nutrient for most bacteria because enzymes like nitrate reductase and cytochromes use it as a cofactor. However, in most aerobic, neutral pH environments, iron is essentially insoluble and not easily available for bacteria to use. Many bacteria respond to this problem by releasing small organic compounds called siderophores that bind and effectively solubilize iron so that it can be transported into the cell for growth. The focus of this study was to learn more about the iron acquisition and especially the transport of iron by the soil bacterium Rhodococcus erythropolis. To fulfill this aim, mutant …


Herpes Simplex Virus Glycoprotein D/Host Cell Surface Interaction Stimulates Chlamydia Trachomatis Persistence Via A Novel Pathway., Jennifer Vanover Dec 2008

Herpes Simplex Virus Glycoprotein D/Host Cell Surface Interaction Stimulates Chlamydia Trachomatis Persistence Via A Novel Pathway., Jennifer Vanover

Electronic Theses and Dissertations

When presented with certain unfavorable environmental conditions, C. trachomatis reticulate bodies (RBs) enter into a viable, yet noncultivable state called persistence. Two hallmarks of persistent chlamydiae are swollen, aberrantly shaped RBs, as viewed by transmission electron microscopy and a decrease in infectious progeny. Several models of chlamydial persistence have been described, including interferon-γ (IFN-γ), IFN-α, IFN-β, and tumor necrosis factor-α-exposure and nutrient deprivation. Previously, we established an in vitro co-infection model of two of the most common sexually transmitted pathogens in the United States, C. trachomatis and Herpes Simplex Virus-2 (HSV). Data from this tissue culture model indicate that: i) …


Identification Of Chlamydial Iron-Responsive Proteins During Intracellular Growth., Brian D. Dill Aug 2008

Identification Of Chlamydial Iron-Responsive Proteins During Intracellular Growth., Brian D. Dill

Electronic Theses and Dissertations

Chlamydia trachomatis is an obligate intracellular bacterium and the most prevalent cause of bacterial sexually transmitted disease. Genital chlamydial infections, marked by chronic, intense inflammation, can lead to genital tissue scarring and infertility and is a contributing factor to development of pelvic inflammatory disease and ectopic pregnancy. Iron is required as a cofactor for numerous highly conserved pathways, and nearly all studied organisms rely on iron for growth. In response to iron restriction, the chlamydial developmental cycle arrests at the intracellular reticulate body stage, resulting in a phenomenon termed persistence. Persistence likely plays a role in chlamydial pathogenesis through the …


Antigen Trafficking Within Chlamydia Trachomatis-Infected Polarized Human Endometrial Epithelial Cells., David Kelley Giles May 2008

Antigen Trafficking Within Chlamydia Trachomatis-Infected Polarized Human Endometrial Epithelial Cells., David Kelley Giles

Electronic Theses and Dissertations

Chlamydia trachomatis serovars D-K are the leading cause of bacterially-acquired sexually transmitted infections in the United States. As an obligate intracellular pathogen, C. trachomatis infects columnar epithelial cells of the genital mucosae and can cause deleterious sequelae such as pelvic inflammatory disease, infertility, and ectopic pregnancy. Several chlamydial antigens reach the host cell cytosol prior to the natural release of chlamydiae at the end of the developmental cycle. While some of these extra-inclusion antigens traffic to the host cell surface, others remain intracellular where they are proposed to influence vital host cell functions and antigen trafficking and presentation. The research …


The Endocytic Protein Numb Regulates App Metabolism And Notch Signaling: Implications For Alzheimer's Disease, George Kyriazis Jan 2008

The Endocytic Protein Numb Regulates App Metabolism And Notch Signaling: Implications For Alzheimer's Disease, George Kyriazis

Electronic Theses and Dissertations

Increased production of amyloid beta (A-beta) peptide, via altered proteolytic cleavage of amyloid protein precursor (APP), and abnormalities in neuronal calcium homeostasis play central roles in the pathogenesis of Alzheimer's disease (AD). Notch1, a membrane receptor that controls cell fate decisions during development of the nervous system, has been linked to AD because it is a substrate for the gamma-secretase protein complex in which mutations cause early-onset inherited AD. Numb is an evolutionarily conserved endocytic adapter involved in the internalization of transmembrane receptors. Mammals produce four Numb isoforms that differ in two functional domains, a phosphotyrosine-binding domain (PTB) and a …


Prostasin Is Expressed In Benign Prostatic Hyperplasia And Regulates Cell Proliferation And Invasion Via Inos, Icam-1, And Cycli, Meghan Hatfield Jan 2008

Prostasin Is Expressed In Benign Prostatic Hyperplasia And Regulates Cell Proliferation And Invasion Via Inos, Icam-1, And Cycli, Meghan Hatfield

Electronic Theses and Dissertations

Prostasin is expressed in normal prostate epithelial cells but down-regulated in prostate cancers, while prostasin re-expression in invasive prostate cancer cells reduced invasion. We examined prostasin expression and function in benign prostatic hyperplasia (BPH). We evaluated prostasin expression in 12 BPH specimens by immunohistochemistry, and evaluated the impact of prostasin silencing by siRNA on the expression of the inducible nitric oxide synthase (iNOS), intercellular adhesion molecule-1 (ICAM-1), and cyclin D1, as well as on cell proliferation and invasion, using the BPH-1 human prostate epithelial cell line model. Prostasin expression was localized in the glands of BPH tissues by immunohistochemistry, in …


Role Of Transient Receptor Potential Canonical-6 (Trpc6) Channel In Metastasis Of Glioblastoma Multiforme, Rajarajeshwari Venkataraman Jan 2008

Role Of Transient Receptor Potential Canonical-6 (Trpc6) Channel In Metastasis Of Glioblastoma Multiforme, Rajarajeshwari Venkataraman

Electronic Theses and Dissertations

Glioblastoma multiforme (GBM) is one of the extremely fatal brain tumors. The main reason that makes it so lethal is its capability to invade and spread to other parts of CNS producing secondary tumors. Among other factors hypoxia, reduced oxygen availability, is linked to higher metastatic potential of cancers. Hypoxia causes numerous changes in genome and proteome of the cell. These changes help a normal cell to adapt to nutritional deficiency, but the same changes can increase the malignancy and metastasis in tumor cells. Extensive research by a number of curious scientists reveal that various pathways involving numerous proteins cross-talk …


Evaluation Of The Efficacy Of Chloroplast-Derived Antigensagainst Malaria, Melissa Schreiber Jan 2008

Evaluation Of The Efficacy Of Chloroplast-Derived Antigensagainst Malaria, Melissa Schreiber

Electronic Theses and Dissertations

Malaria is the most prevalent vector-borne parasitic disease worldwide and a major cause of death from infections. There is a great need to develop a low cost vaccine for malaria to control transmission of infection and impact of disease, due to the emergence of anti-malarial resistance. Two leading blood stage malarial vaccine candidates are the apical membrane antigen-1 (AMA-1) and the merozoite surface protein-1 (MSP-1). The aim of this project is to express malarial antigens in tobacco plants via plastid transformation and deliver them by subcutaneous or oral gavage of minimally processed transplastomic tissue to evaluate their efficacy to elicit …


The Development Of A "Genetic Eyewitness" Profiling System For Low Template Forensic Specimens: Identification Of Novel Protein, Rna, And Dna Biomarkers, Erin Hanson Jan 2008

The Development Of A "Genetic Eyewitness" Profiling System For Low Template Forensic Specimens: Identification Of Novel Protein, Rna, And Dna Biomarkers, Erin Hanson

Electronic Theses and Dissertations

In many criminal investigations, valuable information regarding the physical appearance of suspected perpetrators or the time and order of events that transpired are provided by eyewitness accounts. However, the information obtained from eyewitnesses is often constrained by human recollection or subjective accounts and provides a biased description of the perpetrator's appearance or an inaccurate time line of events. Additionally, in numerous situations eyewitness accounts may not be available. An increasing reliance therefore is placed on the biological evidence recovered during criminal investigations to act as a silent witness, providing unbiased and scientific information that may aid in the resolution of …


The Structural And Folding Characteristics Of The Plasmid-Encoded Toxin From Enteroaggregative Escherichia Coli, Patricia Scaglione Jan 2008

The Structural And Folding Characteristics Of The Plasmid-Encoded Toxin From Enteroaggregative Escherichia Coli, Patricia Scaglione

Electronic Theses and Dissertations

Plasmid-encoded toxin (Pet) from enteroaggregative Escherichia coli is a member of the autotransporter subfamily termed SPATE (serine protease autotransporters of Enterobacteriaceae). Autotransporters, which are the most common Gram-negative secreted virulence factors, contain three functional domains: an amino terminal leader sequence, a mature protein or passenger domain, and a carboxy-terminal β domain. The leader sequence targets the protein to the periplasmic space and the β domain then forms a β-barrel pore in the outer membrane of the bacterium which allows the passenger domain to enter the external milieu. In some cases the passenger domain is cleaved from the β-barrel at the …


Generation Of Recombinant Mouse Embryonic Stem Cell Lines And Theirapplication For In Vivo Bioluminiscence Imaging In The Heart, Ramana Kammili Jan 2008

Generation Of Recombinant Mouse Embryonic Stem Cell Lines And Theirapplication For In Vivo Bioluminiscence Imaging In The Heart, Ramana Kammili

Electronic Theses and Dissertations

Cardiovascular disease is the major cause of death in the United States, with 80 million people suffering from some form of heart disease each year. One major limitation is the inability of the heart to repair the damaged tissue. Stem cell therapy holds enormous promise to repair and regenerate the damaged myocardium, but there are many technical difficulties that must first be overcome. One such difficulty is the present lack of ability to track and assess transplanted stem cells over time in vivo. The central hypothesis of this thesis is that in vivo bioluminescence imaging is a safe and useful …