Engineering Commons^™

In Situ Imaging Of Bacterial Outer Membrane Projections And Associated Protein Complexes Using Electron Cryo-Tomography, Mohammed Kaplan, Georges Chreifi, Lauren Ann Metskas, Janine Liedtke, Cecily R. Wood, Catherine M. Oikonomou, William J. Nicolas, Poorna Subramanian, Lori A. Zacharoff, Yuhang Wang, Yi-Wei Chang, Morgan Beeby, Megan J. Dobro, Yongtao Zhu, Mark J. Mcbride, Ariane Briegel, Carrie L. Shaffer, Grant J. Jensen

Veterinary Science Faculty Publications

The ability to produce outer membrane projections in the form of tubular membrane extensions (MEs) and membrane vesicles (MVs) is a widespread phenomenon among diderm bacteria. Despite this, our knowledge of the ultrastructure of these extensions and their associated protein complexes remains limited. Here, we surveyed the ultrastructure and formation of MEs and MVs, and their associated protein complexes, in tens of thousands of electron cryo-tomograms of ~90 bacterial species that we have collected for various projects over the past 15 years (Jensen lab database), in addition to data generated in the Briegel lab. We identified outer MEs and MVs …

A New Spatially-Resolved Method To Sample Biofilms From Drinking Water Fountains, Yi Liu

McKelvey School of Engineering Theses & Dissertations

A drinking fountain, also called a water fountain, is a facility designed to provide drinking water in public space. It consists of a basin and a spout. The users need to bend down to the stream to collect or drink water. The history of water fountains can be traced back to ancient Rome. Even before potable water was provided to individual homes, water for drinking was already made available to citizens through access to public fountains. Nowadays, drinking water fountains usually exist in public places, like schools, hospitals, and libraries. Many jurisdictions in the United States require drinking fountains to …

Engineered Nanoparticles For Site-Specific Bioorthogonal Catalysis: Imaging And Therapy, Riddha Das

Doctoral Dissertations

Bioorthogonal catalysis offers a strategy for chemical transformations complementary to bioprocesses and has proven to be a powerful tool in biochemistry and medical sciences. Transition metal catalysts (TMCs) have emerged as a powerful tool to execute selective chemical transformations, however, lack of biocompatibility and stability limits their use in biological applications. Incorporation of TMCs into nanoparticle monolayers provides a versatile strategy for the generation of bioorthogonal nanocatalysts known as “nanozymes”. We have fabricated a family of nanozymes using gold nanoparticles (AuNPs) as scaffolds featuring diverse chemical functional groups for controlled localization of nanozymes in biological environments, providing unique strategies for …

Effectiveness Of Biocide Substitution And Management Plan Implementation For The Control Of, Adelmarie Bones

USF Tampa Graduate Theses and Dissertations

After the notorious outbreak and discovery of Legionella bacteria in 1976, the waterborne pathogen was added to the list of disease-causing agents associated with the built environment. Legionella pneumophila was discovered when it was identified as the agent that caused 34 deaths and an outbreak of pneumonia-like symptoms in several attendees of the 1976 American Legion Convention held in Philadelphia (OSHA, 2017).

Recently published data from the year 2015 reported more than 6,000 Legionnaires’ cases identified in the United States (CDC, 2016). This is a concerning number given that one in every ten infected persons will die of the disease. …

Development Of Pyrf-Based Genetic System For Targeted Gene Deletion In Clostridium Thermocellum And Creation Of A Pta Mutant, Shital A. Tripathi, Daniel G. Olson, D. Aaron Argyros, Bethany B. Miller, Trisha F. Barrett, Daniel M. Murphy, Jesse D. Mccool, Anne K. Warner, Vineet B. Rajgarhia, Lee R. Lynd, David A. Hogsett, Nicky C. Caiazza

Dartmouth Scholarship

We report development of a genetic system for making targeted gene knockouts in Clostridium thermocellum, a thermophilic anaerobic bacterium that rapidly solubilizes cellulose. A toxic uracil analog, 5-fluoroorotic acid (5-FOA), was used to select for deletion of the pyrF gene. The ΔpyrF strain is a uracil auxotroph that could be restored to a prototroph via ectopic expression of pyrF from a plasmid, providing a positive genetic selection. Furthermore, 5-FOA was used to select against plasmid-expressed pyrF, creating a negative selection for plasmid loss. This technology was used to delete a gene involved in organic acid production, namely pta, which encodes …

Cold Plasma Technology: Bactericidal Effects On Geobacillus Stearothermophilus And Bacillus Cereus Microorganisms, Angela D. Morris, Gayle B. Mccombs, Tamer Akan, Wayne L. Hynes, Mounir Laroussi, Susan L. Tolle

Dental Hygiene Faculty Publications

Introduction: Cold plasma, also known as Low Temperature Atmospheric Pressure Plasma (LTAPP) is a novel technology consisting of neutral and charged particles, including free radicals, which can be used to destroy or inactivate microorganisms. Research has been conducted regarding the effect of cold plasma on gram-positive bacteria; however, there is limited research regarding its ability to inactivate the spore-formers Geobacillus stearothermophilus and Bacillus cereus.

Purpose: The purpose of this study was to determine if cold plasma inactivates G. stearothermophilus and B. cereus vegetative cells and spores.

Methods: Nine hundred eighty-one samples were included in this study (762 experimental and …