Life Sciences Commons^™

Production And Harvest Of Microalgae In Wastewater Raceways With Resource Recycling, Alexander Colin Roberts

Master's Theses

Microalgae can be grown on municipal wastewater media to both treat the wastewater and produce feedstock for algae biofuel production. However the reliability of treatment must be demonstrated, as well as high areal algae productivity on recycled wastewater media and efficient sedimentation harvesting. This processes was studied at pilot scale in the present research.

A pilot facility was operated with nine CO₂-supplemented raceway ponds, each with a 33-m² surface area and a 0.3-m depth, continuously from March 6, 2013 through September 24, 2014. The ponds were operated as three sets of triplicates with two sets continuously fed …

Demographics And Transfer Of Escherichia Coli Within Bos Taurus Populations, Joshua Ryan Dillard

Master's Theses

In the United States, symptoms caused by pathogenic strains of Escherichia coli are on the rise. A major source of these pathogenic strains is the E. coli in the digestive tract of cattle. The purpose of this project was to determine if E. coli are transferred between individuals of the same species and if interspecies transmission is possible. Proximity of cattle was also studied as a contributing factor to the transfer of E. coli. To accomplish this goal, E. coli isolates from cattle and cohabitating ground squirrels were compared through a new method of bacterial strain typing called pyroprinting. …

Virulence Gene Expression Of Vibrio Parahaemolyticus In The Viable But Nonculturable State, Tiffany Pui-Yun Tse

Master's Theses

Vibrio parahaemolyticus is a food-borne pathogen commonly associated with the consumption of raw or undercooked seafood resulting in primary infections of the human gastrointestinal tract. It is estimated to cause about 4500 illnesses each year in the United States. However, infection from this food-borne pathogen can be avoided if this organism is detected in the implicated food, prior to consumption. Current standard methods of detecting this organism are dependent on the culturability of the bacteria. Detection based on an organism’s culturability may be problematic as V. parahaemolyticus has been known to exist in a viable but nonculturable (VBNC) state. Bacteria …

Detection Of Hcmv Viral Il-10 (Vil-10) In Healthy Blood Donors, Vivian P. Young

Master's Theses

Human cytomegalovirus (HCMV) is widespread in the general population and can establish lifelong latency with expression of a limited subset of viral genes. The UL111A gene is expressed during both lytic and latent infection, and at least two protein isoforms are produced. During lytic infection, the full length transcript yields cmvIL-10, a potent immunosuppressive viral ortholog of human IL-10 (hIL-10). Alternative splicing of the UL111A transcript yields a truncated protein, LAcmvIL-10, which is expressed during both lytic and latent infection but with a limited range of immunosuppressive functions. The two viral cytokines, collectively termed viral IL-10 (vIL-10), are identical in …

Stressed Induced Changes In Karenia Brevis Ribosomal Rna, David Scott Jayroe

Master's Theses

Karenia brevis is a toxic marine dinoflagellate that causes harmful algal blooms (HABs), also known as red tides, in the Gulf of Mexico. These blooms are responsible for massive fish kills, shellfish bed contaminations, adverse human health effects, and vast economic loss. For these reasons, extensive research has gone into understanding the mechanisms and dynamics of bloom behavior by studying K. brevis in the field and in the lab. In order to understand higher order bloom behavior and dynamics it is imperative to understand K. brevis at the cellular level. In growing K. brevis in vitro under a variety of …

Impacts Of The Deepwater Horizon Oil Spill On Microbial-Mediated Cellulose Decomposition In Mississippi Gulf Coast Salt Marshes, Jerrid Shawn Boyette

Master's Theses

Field studies were conducted to examine the effects of the Deepwater Horizon oil spill on rates of marsh organic matter decomposition. Decomposition in surface and subsurface marsh sediments was assessed in stands of Spartina alterniflora and Juncus roemerianus in 9 Mississippi Gulf Coast marshes exposed to differing oiling intensities. The cotton strip bioassay technique was used as a proxy for cellulose decomposition. In addition, rates of microbial respiration, fungal biomass (ergosterol) and nutrients (C:N, C:P) of surface sediment cotton strips were also quantified. Subsurface cotton strip decay, as determined by losses in tensile strength, were significantly different among marsh …

Exploring The Physiological Role Of Vibrio Fischeri Pepn, Sally L. Cello

Master's Theses

The primary contributor to Vibrio fischeri aminopeptidase activity is aminopeptidase N, PepN. Colonization assays revealed the pepN mutant strain to be deficient at forming dense aggregates and populating the host’s light organ compared to wildtype within the first 12 hours of colonization; however the mutant competed normally at 24 hours. To address the role of PepN in colonization initiation and establish additional phenotypes for the pepN mutant strain, stress response and other physiological assays were employed. Marked differences were found between pepN mutant and wildtype strain in response to salinity, acidity, and antibiotic tolerance. This study has provided a foundation …

The Effects Of Stress And Alcohol On Hiv-1 Latency, Sarah Ilene Talley

Master's Theses

A major barrier to HIV eradication is the persistence of latent viral reservoirs that exist despite antiretroviral therapy. In order to develop effective therapeutics, a comprehensive understanding of latency and factors driving the formation of the latent reservoir is needed. As stress and alcohol are common comorbidities associated with HIV infection, the goal of this research was to determine how stress and alcohol could affect HIV-latency. Specifically, we hypothesized that the ability of latent proviruses to be reactivated by “shock and kill” approaches would be altered by glucocorticoid and ethanol treatments, and prolonged ethanol exposure would affect the size of …

The Role Of Pidd Protein In Adenoviral Induction Of Apoptosis, Iris Teresa Figueroa

Master's Theses

The Adenovirus E1A gene sensitizes cells to genetic insults and apoptosis, most notably in response to cytotoxic factors from innate immune cells. The mechanisms by which E1A sensitizes cells to apoptotic stressors have not been fully elucidated, however E1A actively represses NF-κB anti-apoptotic defenses, thereby sensitizing cells to alternative apoptotic cascades. Recent studies alternatively indicate that E1A also actively induces Caspase-2 activation and mitochondrial injury in the presence of certain cytotoxic injuries.

Caspase-2 is cleaved and activated in a large complex consisting of p53-inducible protein with a death domain (PIDD), an adaptor protein RAIDD, and pro-caspase 2. PIDD auto-proteolyzes into …

The Contribution Of The Female Urinary Microbiota To Lower Urinary Tract Symptoms, Travis Kyle Price

Master's Theses

The recent finding that urine is not sterile raises a lot of questions: first and foremost, what microorganisms are present, and are these microorganisms correlated with clinical urinary symptoms? Recent work on the female urinary microbiota (FUM) found that the communities of microorganisms differ between women with no lower urinary tract symptoms (LUTS) and those with Urgency Urinary Incontinence (UUI) a form of over-active bladder syndrome. Specifically, a diverse or dysbiotic urinary microbiota was found to be associated with symptomatic women. This suggests the possibility that the FUM can be contributing to urinary symptoms. Conversely, it could also suggest that …

Malaria Transmission Blocking Vaccines, Lukasz Jacek Sewera

Master's Theses

Malaria affects 198 million people and kills 584,000 each year, predominantly in Sub-Saharan Africa (WHO). The most severe form of malaria is caused by the protozoan parasite Plasmodium falciparum. Development of a vaccine against P. falciparum has been hindered by its complex life cycle with multiple antigenically distinct human and mosquito stages. To effectively prevent disease and reduce the parasite burden in populations, a vaccine will need to target multiple stages, including blocking transmission at the mosquito stage.

Antibodies generated against P. falciparum mosquito stage antigen Pfs25 can prevent parasite transmission from humans to mosquitoes. However, Pfs25 is poorly immunogenic …

The Role Of Central Metabolism And Electron Transport In Biofilm Formation By Vibrio Fischeri, Jakob Michael Ondrey

Master's Theses

Biofilms protect bacteria from environmental threats, including antibiotics; thus, biofilms formed during infections pose an increasing threat to human health. A natural model used to study biofilm formation in the context of a host is the symbiosis between Vibrio fischeri and its host, the squid Euprymna scolopes. Successful colonization depends on the formation of a biofilm and genes involved in making the polysaccharide matrix component, syp. In culture, biofilm phenotypes, including the formation of wrinkled colonies, similarly depend on syp. However, little is known about other factors that contribute to this phenotype. To expand the utility of currently available genetic …

Investigating The Role Of Cysteine In Biofilm Formation By Vibrio Fischeri, Priyanka Abhishek Singh

Master's Theses

Biofilms are an important area of medical research because bacterial biofilms can form on implants such as catheters and are highly resistant to antibiotics and other antimicrobials. The symbiosis between Vibrio fischeri-Euprymna scolopes, is good model to study biofilm. V. fischeri has 18 gene polysaccharide locus, syp, that is required for biofilm formation and colonization. A recent mutant study suggested the possibility that cysteine biosynthetic genes were involved in biofilm formation by V. fischeri, including cysH, cysJ, cysK, and cysN. My results supported a role for cysK and, to a lesser extent, cysH in biofilm formation. Finally, I have data …