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Breaking Virulent: The Coincidental Evolution Of Virulence Factors In Bacteria., Rhiannon Emmanuelle Cecil
Breaking Virulent: The Coincidental Evolution Of Virulence Factors In Bacteria., Rhiannon Emmanuelle Cecil
Electronic Theses and Dissertations
Understanding how innocuous organisms can evolve to be pathogenic to humans is of increasing global concern. Further, understanding how existing pathogens may evolved to be more virulent is also vital to our ability to provide healthcare to people afflicted with diseases that promote chronic bacterial infections, such as cystic fibrosis. With the rise of antibiotic resistance in both bacteria and fungi it is paramount that new therapeutics are identified. Understanding what mutations occur that result in increased virulence in microbes can potentially provide new targets for antimicrobial drugs to combat antibiotic resistance. The Coincidental Evolution Hypothesis is a fundamental hypothesis …
Tobacco Enhances Bacterial-Induced Periodontal Bone Loss In Mice., Mina Iskander
Tobacco Enhances Bacterial-Induced Periodontal Bone Loss In Mice., Mina Iskander
Electronic Theses and Dissertations
Background: Tobacco smoking is the leading environmental risk factor for periodontal diseases. Delineation of the mechanisms underlying tobacco-induced or exacerbated periodontitis is hampered by the lack of an appropriate and reliable animal model. Hypothesis: We hypothesized that Porphyromonas-gingivalis-infected, cigarette smoke-exposed mice would represent reproducible models of acute (ligature model) and chronic (oral gavage model) tobacco-enhanced periodontitis that reflect multiple aspects of the disease noted in human smokers. Methods: In a chronic oral gavage disease model, Balb/c mice (6-8 weeks, 4 groups of n = 6 per group) were exposed to smoke produced by a Teague-10 smoking machine from 1R6F research …
Function Of The Enterobactin Operon Of A. Actinomycetemcomitans In The Presence Of Catecholmines And Iron., Taylor Johnson
Function Of The Enterobactin Operon Of A. Actinomycetemcomitans In The Presence Of Catecholmines And Iron., Taylor Johnson
Electronic Theses and Dissertations
Background: Aggregatibacter actinomycetemcomitans (Aa) possesses a two-component system, QseBC, which is key in biofilm formation/virulence and is activated in the presence of iron-catecholamine complexes. Aa does not synthesize enterobactin, a catechol-based siderophore, yet possesses the machinery for recognition and uptake. We hypothesize that Aa is able to acquire iron by catecholamine mediation through the enterobactin receptor/transporter. Methods: By insertional mutation, we attempted to delete the enterobactin permease from the genome using suicide vector pJT1. A growth curve of truncated mutant ΔfepA was also conducted to observe growth in the presence of iron and catecholamines. Statistical significance was determined by ANOVA …