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The Eastern Oyster Microbiome And Its Implications In The Marine Nitrogen Cycle, Ann Arfken Jan 2017

The Eastern Oyster Microbiome And Its Implications In The Marine Nitrogen Cycle, Ann Arfken

Dissertations, Theses, and Masters Projects

Microbial communities associated with a particular space or habitat, or microbiomes, play significant roles in host health and the regulation of biogeochemical cycles. In oysters these microbiomes may be important contributors in the removal of biologically available nitrogen (N) from the coastal and marine environment through the process of denitrification. Denitrification is the microbially mediated step-wise reduction of nitrate (NO3-) or nitrite (NO2-) to N2 gas. Excess nitrogen in the Chesapeake Bay has been implicated in the increase of eutrophication and other detrimental effects including harmful algal blooms, hypoxia, and loss of benthic communities. Oyster reefs have been shown to ...


Adaptation Of H Pylori To Changing Environments Based On Allelic Variation Of Sensor Histidine Kinase Arss, Monique R. Bennett Jan 2014

Adaptation Of H Pylori To Changing Environments Based On Allelic Variation Of Sensor Histidine Kinase Arss, Monique R. Bennett

Dissertations, Theses, and Masters Projects

No abstract provided.


Investigation Of Prophage In Clinical Isolates Of H Pylori, Kevin Alexander Leslie Jan 2013

Investigation Of Prophage In Clinical Isolates Of H Pylori, Kevin Alexander Leslie

Dissertations, Theses, and Masters Projects

No abstract provided.


Abundance, Structure And Function Of Zooplankton-Associated Bacterial Communities Within The York River, Va, Samantha L. Bickel Jan 2013

Abundance, Structure And Function Of Zooplankton-Associated Bacterial Communities Within The York River, Va, Samantha L. Bickel

Dissertations, Theses, and Masters Projects

Mesozooplankton function as microbial microhabitats and can support concentrations of bacteria orders of magnitude higher than in the surrounding water. These zooplankton-associated bacteria can have much higher production rates than their free-living counterparts. Portions of the zooplankton microhabitat may also be anoxic and provide refuge for anaerobic bacteria and their associated processes within the oxygenated water column. Despite their common presence in the marine environment, zooplankton-associated bacteria are largely ignored by microbial ecologists and zooplankton ecologists alike. Consequently, factors which influence zooplanktonassociated bacterial abundance, community composition and function, and how zooplankton-associated bacteria compare to free-living bacteria are not well known ...


Detection And Infectivity Of Human Adenovirus In Wastewater Effluent, Biosolids, And Shellfish, And Its Persistence In Estuarine Water, Wenda Lee Quidort Jan 2013

Detection And Infectivity Of Human Adenovirus In Wastewater Effluent, Biosolids, And Shellfish, And Its Persistence In Estuarine Water, Wenda Lee Quidort

Dissertations, Theses, and Masters Projects

The United States Environmental Protection Agency (USEPA) has established the Total Coliform Rule as an indication of health risks associated with microbial contamination of drinking and ground water. In addition, the fecal coliform test is used as an indicator to reflect the suitability of use by consumers of class A biosolids. However, numerous studies have shown that bacterial indicators are not predictive of enteric viruses, such as human adenovirus (HAdV), which are much more resistant to treatment methods than bacteria. Enteric viral contamination of estuarine waters and locally-harvested shellfish as a result of receiving effluent from wastewater treatment plants, as ...


Transcriptional Regulation Of The Acetone Carboxylase Operon Via Two-Component Signal Transduction In Helicobacter Pylori, Vanessa H. Quinlivan-Repasi Jan 2012

Transcriptional Regulation Of The Acetone Carboxylase Operon Via Two-Component Signal Transduction In Helicobacter Pylori, Vanessa H. Quinlivan-Repasi

Dissertations, Theses, and Masters Projects

No abstract provided.


An Investigation Of The Polymorphic Arss Gene Of Helicobacter Pylori, Daniel Ross Hallinger Jan 2011

An Investigation Of The Polymorphic Arss Gene Of Helicobacter Pylori, Daniel Ross Hallinger

Dissertations, Theses, and Masters Projects

No abstract provided.


Genetic Diversity Of The Pathogen Streptococcus Parauberis Isolated From Bovine And Piscine Hosts, Stephen Douglas Cole Jan 2011

Genetic Diversity Of The Pathogen Streptococcus Parauberis Isolated From Bovine And Piscine Hosts, Stephen Douglas Cole

Dissertations, Theses, and Masters Projects

No abstract provided.


Analysis Of Sequence Variation At Two Helicobacter Pylori Genetic Loci Potentially Involved In Virulence, George Warren Liechti Jan 2008

Analysis Of Sequence Variation At Two Helicobacter Pylori Genetic Loci Potentially Involved In Virulence, George Warren Liechti

Dissertations, Theses, and Masters Projects

No abstract provided.


Pathogenicity Of The Purportedly Toxic Dinoflagellates Pfiesteria Piscicida And Pseudopfiesteria Shumwayae And Related Species, Vincent J. Lovko Jan 2008

Pathogenicity Of The Purportedly Toxic Dinoflagellates Pfiesteria Piscicida And Pseudopfiesteria Shumwayae And Related Species, Vincent J. Lovko

Dissertations, Theses, and Masters Projects

The heterotrophic dinoflagellates Pfiesteria piscicida and Pseudopfiesteria shumwayae (here referred to as Pfiesteria) have been reported to secrete potent toxins responsible for inducing lesions in Atlantic menhaden, causing deaths of fishes in natural systems and laboratory assays and impacting human health. Many aspects of Pfiesteria biology and ecology have been questioned, including its complicated life-cycle, its role in fish kills, fish lesion events and human health effects as well as its ability to produce toxins. Although the involvement of Pfiesteria in major estuarine fish kills and lesion events has been disputed, there is a demonstrated ability of these organisms to ...


An Evaluation Of Norovirus Persistence In Estuarine Water And Of Methods For Its Detection In Treated Sewage Effluent, Margaret H. Fagan Jan 2008

An Evaluation Of Norovirus Persistence In Estuarine Water And Of Methods For Its Detection In Treated Sewage Effluent, Margaret H. Fagan

Dissertations, Theses, and Masters Projects

No abstract provided.


The Infection Dynamics Of Pav1 In The Caribbean Spiny Lobster Panulirus Argus, Caiwen Li Jan 2007

The Infection Dynamics Of Pav1 In The Caribbean Spiny Lobster Panulirus Argus, Caiwen Li

Dissertations, Theses, and Masters Projects

Panulirus argus Virus 1 (PaV1) is an emerging disease in Caribbean spiny lobster Panulirus argus. It is considered a threat to the lobster industry in the Florida Keys. In order to understand the infection dynamics of the PaV1 virus in the lobster host, a sensitive and specific fluorescence in situ hybridization (FISH) assay was developed for diagnosis of PaV1 in lobsters. The lower limit of detection using the 110-bp DNA probe in a dot-blot hybridization for PaV1 was 10 pg of cloned DNA template and 10 ng of genomic DNA extracted from hemolymph of diseased spiny lobster. The probe specifically ...


The Role Of Bacteria-Particle Interactions In Marine Snow Dynamics, Emily M. Yam Jan 2007

The Role Of Bacteria-Particle Interactions In Marine Snow Dynamics, Emily M. Yam

Dissertations, Theses, and Masters Projects

Marine snow aggregates are one of the primary vehicles for deep-sea carbon sequestration. Bacterial activity on marine snow affects both degradation and aggregation processes that determine the flux of carbon to depth, biogeochemical cycling, and microbial food webs. The microscale processes occurring on aggregates depend on specific interactions between bacteria and particles. In this thesis, I describe two such interactions which have larger scale implications on marine snow dynamics: (1) the effects of starvation on bacterial motility and colonization behaviors on marine aggregates and (2) interactions between bacteria and phytoplankton which could contribute to the production of TEP.

Current models ...


Iron And Carbon Limitation Of Prokaryotic Growth In The Ocean, Jacques L. Oliver Jan 2005

Iron And Carbon Limitation Of Prokaryotic Growth In The Ocean, Jacques L. Oliver

Dissertations, Theses, and Masters Projects

Studies were undertaken to examine the roles of iron and carbon in modulating prokaryotic growth in the ocean. The context of the first study was an open-open iron fertilization experiment in the high nutrient, low chlorophyll (HNLC) regime in the Southern Ocean. The context of the second study was the oligotrophic, iron-replete, and organic carbon-limited northwest Sargasso Sea. Experimental sea water cultures were amended with an iron chelator, desferrioxamine B (DFOB), and other nutrients to examine the effects of iron and carbon limitation on growth. In the first study prokaryotic abundance, carbon production, and growth rate increased in response to ...


Do Sulfide-Oxidizing Bacteria Produce Light?, Rachel Elizabeth Ann Horak Jan 2004

Do Sulfide-Oxidizing Bacteria Produce Light?, Rachel Elizabeth Ann Horak

Dissertations, Theses, and Masters Projects

No abstract provided.


Plumage As A Habitat For Bacilli, Justine M. Whitaker Jan 2004

Plumage As A Habitat For Bacilli, Justine M. Whitaker

Dissertations, Theses, and Masters Projects

No abstract provided.


Dynamics Of The Host-Parasite Interaction: In Vitro Correlates Of Crassostrea-Induced Modulation Of Perkinsus Marinus Function, Christopher G. Earnhart Jan 2004

Dynamics Of The Host-Parasite Interaction: In Vitro Correlates Of Crassostrea-Induced Modulation Of Perkinsus Marinus Function, Christopher G. Earnhart

Dissertations, Theses, and Masters Projects

Perkinsus marinus is an alveolate protozoan parasite of the eastern oyster (Crassostrea virginica) which is responsible for much of the decline in United States oyster populations. Perkinsus marinus can be cultured in vitro, but is rapidly attenuated in the process. Supplementation of a protein-free medium with oyster products altered proliferation, changed protease expression in the parasite extracellular products (ECP), induced morphological forms typically seen in vivo, and partially reversed parasite attenuation. Supplements derived from dissected oyster tissues were used to determine if these changes could be differentially elicited. These supplements, with the exception of adductor muscle, reduced proliferation. Whole oyster ...


Pathobiology Of Mycobacteria In Striped Bass (Morone Saxatilis), David T. Gauthier Jan 2004

Pathobiology Of Mycobacteria In Striped Bass (Morone Saxatilis), David T. Gauthier

Dissertations, Theses, and Masters Projects

Striped bass (Morone saxatilis) in Chesapeake Bay, USA, are experiencing an epizootic of mycobacteriosis. This disease, caused by bacteria in the genus Mycobacterium, causes granulomatous lesions of the skin and viscera. Diseased fish are often emaciated, and fish with skin lesions may be significantly disfigured. The overall goal of this work was to examine aspects of the pathobiology of mycobacteria in striped bass via laboratory exposure studies and cellular assays. Striped bass were injected intraperitoneally with a sublethal dose of Mycobacterium marinum, M. shottsii, or M. gordonae and sampled for histology and bacteriology at regular intervals to 45 weeks post-injection ...


Microbial Dynamics And Biogeochemistry In The North Pacific Subtropical Gyre, Matthew J. Church Jan 2003

Microbial Dynamics And Biogeochemistry In The North Pacific Subtropical Gyre, Matthew J. Church

Dissertations, Theses, and Masters Projects

The research presented in this dissertation describes the influence of planktonic bacterial growth on upper ocean organic matter dynamics in the North Pacific Subtropical Gyre (NPSG). Examination of the temporal dynamics in dissolved organic matter (DOM) was coupled with investigations that targeted the influence of heterotrophic bacterial production (HBP) on organic matter fluxes in the NPSG. Nine cruises to the Hawaii Ocean Time-series field site Station ALOHA revealed that HBP accounted for a large flux of organic carbon in the upper ocean of the NPSG. HBP was significantly enhanced by sunlight, with photoenhancement of HBP accounting for 3.2 mol ...


Bacterial Properties And Dissolved Organic Matter Distributions In The Black Sea, Jessica A. Morgan Jan 2003

Bacterial Properties And Dissolved Organic Matter Distributions In The Black Sea, Jessica A. Morgan

Dissertations, Theses, and Masters Projects

No abstract provided.


Molecular Characterization Of Cultured Perkinsus Marinus Isolates, Gwynne D. Brown Jan 2001

Molecular Characterization Of Cultured Perkinsus Marinus Isolates, Gwynne D. Brown

Dissertations, Theses, and Masters Projects

Perkinsus marinus is the causative agent of the oyster disease Dermo in the eastern oyster, Crassostrea virginica. In vitro propagation of the parasite has led to the establishment of multiple isolates by several investigators. Little work, however, has been done to characterize different isolates. In this study multiple isolates were examined for genetic and biochemical diversity. at two loci, the ITS region and the ATAN region, there was as much intra-isolate genetic variation among DNA sequences of some isolates as there was inter-isolate variation. Variation was also observed at a third loci, a subtilisin-like serine protease gene. This is the ...


Characterization Of Iron-Bearing Solids Used By Naturally-Occurring Microbes In The Anaerobic Degradation Of Hydrocarbons, David C. Powell Jan 2000

Characterization Of Iron-Bearing Solids Used By Naturally-Occurring Microbes In The Anaerobic Degradation Of Hydrocarbons, David C. Powell

Dissertations, Theses, and Masters Projects

No abstract provided.


Carbon Production And Growth Physiology Of Heterotrophic Bacteria In A Subtropical Coral Reef Ecosystem, Peter Dylan Countway Jan 1999

Carbon Production And Growth Physiology Of Heterotrophic Bacteria In A Subtropical Coral Reef Ecosystem, Peter Dylan Countway

Dissertations, Theses, and Masters Projects

No abstract provided.


Bacterial Dynamics And Community Structure In The York River Estuary, Gary Edward Schultz Jr Jan 1999

Bacterial Dynamics And Community Structure In The York River Estuary, Gary Edward Schultz Jr

Dissertations, Theses, and Masters Projects

Bacterial community dynamics were investigated over seasonal and basin scales within the York River, VA, estuary. Various parameters characterizing bacterioplankton dynamics were measured weekly at a single station (March 1996 through May 1997) and monthly at six stations (June 1996 through May 1997) spanning the entire salinity gradient (0 - ca. 20 psu over 60 km). Bacterial abundance and production were found to be high throughout the estuary. Bacterial abundance ranged from 4.4 x 108 to 1.3 x 1010 cells-liter-1Incorporation of 3H-thymidine ranged from 10 to 863 pmol-liter-1-hr-1 while 3H-leucine incorporation rates ranged from 25 to 1963 pmol-liter -1-hr-1 ...


Limitation Of Bacterial Growth By Dissolved Organic Matter And Iron In The Southern Ocean, Matthew J. Church Jan 1999

Limitation Of Bacterial Growth By Dissolved Organic Matter And Iron In The Southern Ocean, Matthew J. Church

Dissertations, Theses, and Masters Projects

No abstract provided.


Effects Of Simulated Sediment Resuspension Events On The Abundance Of Water Column Bacteria Of Tomales Bay, California, Christopher J. Collumb Jan 1995

Effects Of Simulated Sediment Resuspension Events On The Abundance Of Water Column Bacteria Of Tomales Bay, California, Christopher J. Collumb

Dissertations, Theses, and Masters Projects

No abstract provided.


Elevated Temperatures Perturb Lipopolysaccharide Leading To Increased Serum Complement Sensitivity In Most Gram-Negative Bacteria, Lori Snyder Dudgeon Jan 1995

Elevated Temperatures Perturb Lipopolysaccharide Leading To Increased Serum Complement Sensitivity In Most Gram-Negative Bacteria, Lori Snyder Dudgeon

Dissertations, Theses, and Masters Projects

No abstract provided.


Effects Of Sunlight And Seasonal Temperature On Persistence Of Four Bacteriophages In An Estuarine Environment, Terri A. Muller Jan 1995

Effects Of Sunlight And Seasonal Temperature On Persistence Of Four Bacteriophages In An Estuarine Environment, Terri A. Muller

Dissertations, Theses, and Masters Projects

No abstract provided.


Frna Coliphages As A Viral Indicator Of Sewage Pollution In An Estuary, David Miller Boyd Jan 1990

Frna Coliphages As A Viral Indicator Of Sewage Pollution In An Estuary, David Miller Boyd

Dissertations, Theses, and Masters Projects

No abstract provided.


Growth Rate And Grazing Dynamics Of Coccoid Cyanobacteria In The Lower Chesapeake Bay, Carol J. Falkenhayn Jan 1990

Growth Rate And Grazing Dynamics Of Coccoid Cyanobacteria In The Lower Chesapeake Bay, Carol J. Falkenhayn

Dissertations, Theses, and Masters Projects

No abstract provided.