Microbiology Commons^™

The Elasmobranch-Microbe Relationship: Trimethylamine N-Oxide Synthesis, Urea Hydrolysis, And Microbe-Osmolyte Interactions In The Atlantic Stingray, Dasyatis Sabina, Kaitlin Kelly Doucette

Master's Theses

The elasmobranch osmoregulatory strategy is predicated on the accumulation of nitrogenous compounds, primarily urea and trimethylamine n¬-oxide (TMAO). Despite the abundance of these plasma osmolytes, it is notable that elasmobranchs appear to lack urease and TMA oxidase (Tmase), enzymes that scavenge urea-nitrogen and synthesize TMAO, respectively. However, urease and Tmase are found in many species of bacteria. Therefore, I hypothesized that intestinal bacteria are responsible for urease and Tmase activity in elasmobranchs. Absent dietary nitrogen sources, I evaluated the effects of reduced intestinal microbiota on osmoregulation in Atlantic stingray (Dasyatis sabina) in vivo. D. sabina were given …

Fecal Bacterial Communities As An Indicator Of Trophic Interactions Among Anuran Larvae, Steven Jacob Everman

Master's Theses

Anurans are mass spawners, often with multiple females spawning together, resulting in thousands of tadpoles sharing a habitat. Such large numbers of tadpoles with limited dispersal can lead to intense competition for resources. Inter and intra-specific competition for food could have negative impacts on the growth and survival of smaller tadpoles. Fecal bacterial communities have the potential to be used as indicators of changes in diet making it possible to determine if tadpoles in the wild are eating the same food or not. After feeding on two prepared diets that differed in the percentage of complex carbohydrates, the fecal bacterial …

Epidemiology Of White Spot Syndrome Virus In The Daggerblade Grass Shrimp (Palaemonetes Pugio) And The Gulf Sand Fiddler Crab (Uca Panacea), Muhammad

Dissertations

Ever since the first outbreaks of White spot syndrome virus (WSSV), which causes White Spot Disease (WSD), in Asia in the early 1990s, the pathogen has been a major constraint to the profitability of the shrimp aquaculture industry across the globe. WSSV has a broad host range and is routinely detected in wild decapod crustaceans. In the present study, two common species in the tidal salt marsh along the northern coast of the Gulf of Mexico, the daggerblade grass shrimp (Palaemonetes pugio) and the Gulf sand fiddler crab (Uca panacea), were investigated for their role as …

A Microbiomic Approach To The Characterization Of The Impacts And Influences Of Viral, Bacterial, And Harmful Algal Bloom Toxins On The Bottlenose Dolphin, Corey David Russo

Dissertations

As apex predators that display high site fidelity Tursiops truncatus (bottlenose dolphin) are indicators of marine ecosystem health. Bottlenose dolphins, additionally, display pathogenesis and immune response similar to that of humans. Humans and coastal bottlenose dolphins, in particular, are constantly exposed to the same industrial, agricultural and domestic toxins and pathogens, contaminants and pollutants. Thus, studies on the bottlenose dolphin are also valuable in bridging the gap between ocean and human health. Bottlenose dolphins are susceptible to viral bacterial and toxin infection. Infection in the bottlenose dolphin manifests itself in the form of mass stranding events, unusual mortality events, chronic …

Lignocellulose As Carbon Source Promotes Bacterial Synergism And Reduces Antagonism, Yijie Deng

Dissertations

Lignocellulose decomposes slowly in nature because it consists of complex polymers resistant to enzymatic degradation by most organisms. Some bacteria are capable of producing cellulolytic enzymes but the way in which bacteria interact within a community to enhance degradation of the recalcitrant substrate is poorly understood. A better understanding of how bacterial interactions affect lignocellulose degradation would provide potential approaches to improve the efficiency of lignocellulose degradation for biofuel production.

To study whether bacterial interactions enhance lignocellulose degradation, I grew environmental bacterial isolates in mixed cultures and pure cultures. I found that bacterial synergism in mixed cultures was common in …

Synergistic Growth In Bacteria Depends On Substrate Complexity, Yi-Jie Deng, Shiao Y. Wang

Faculty Publications

Both positive and negative interactions among bacteria take place in the environment. We hypothesize that the complexity of the substrate affects the way bacteria interact with greater cooperation in the presence of recalcitrant substrate. We isolated lignocellulolytic bacteria from salt marsh detritus and compared the growth, metabolic activity and enzyme production of pure cultures to those of three-species mixed cultures in lignocellulose and glucose media. Synergistic growth was common in lignocellulose medium containing carboxyl methyl cellulose, xylan and lignin but absent in glucose medium. Bacterial synergism promoted metabolic activity in synergistic mixed cultures but not the maximal growth rate (μ). …