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Full-Text Articles in Microbiology
The Spatial, Temporal, And Ecological Constraints Of Plant-Host Associated Microbial Communities, Jonathan Dickey
The Spatial, Temporal, And Ecological Constraints Of Plant-Host Associated Microbial Communities, Jonathan Dickey
Doctoral Dissertations
With the development of next generation sequencing technology, ecologists have recently been able to describe microbial communities across a wide array of niches at an accelerated pace. De-novo-based patterns in richness and relative abundance have been described for bacterial and fungal communities in terrestrial, aquatic, and host-associated microhabitats. A recent synthesis has shown that these communities exhibit similar geographical patterns that have been traditionally described for plant and animals. Yet, there is a lack of hypothesis-based research for host-associated microbial communities. Throughout this dissertation, I will address how spatial scale, sequencing resolution, and manipulative rainfall exclusion govern host-associated microbial communities …
Theoretical And Quantitative Methods Connecting Characterizing Micoribal Metabolism Diversity: Implciations From Phylogenetics, Community Diversity, And Organic Geochemistry, Taylor Royalty
Doctoral Dissertations
Biogeochemistry is controlled by microorganisms obtaining nutrients and energy. Thus, microbial metabolisms directly link microbial ecology and geochemistry. The extent that microbial ecology and geochemistry microbial ecology and geochemistry affects the other requires constraint on the spatiotemporal distribution and abundance of microbial metabolisms with respect to geochemistry, or the microbial niches. Elucidating microbial metabolisms was challenging prior to the advent of ‘omics sequencing technologies, as most microbial lineages lack cultured representatives. Although revolutionizing microbial ecology, challenges still exist in fully leveraging information derived from ‘omics technologies. This dissertation attempts to address a small subset of these challenges that include quantifying …
Bacterial Diversity And Function Within An Epigenic Cave System And Implications For Other Limestone Cave Systems, Kathleen Merritt Brannen-Donnelly
Bacterial Diversity And Function Within An Epigenic Cave System And Implications For Other Limestone Cave Systems, Kathleen Merritt Brannen-Donnelly
Doctoral Dissertations
There are approximately 48,000 known cave systems in the United States of America, with caves formed in carbonate karst terrains being the most common. Epigenic systems develop from the downward flow of meteoric water through carbonate bedrock and the solutional enlargement of interconnected subsurface conduits. Despite carbonate karst aquifers being globally extensive and important drinking water sources, microbial diversity and function are poorly understood compared to other Earth environments. After several decades of research, studies have shown that microorganisms in caves affect water quality, rates of carbonate dissolution and precipitation, and ecosystem nutrition through organic matter cycling. However, limited prior …
Diversity And Function Of Sulfur Cycling Microorganisms In Sediments From Subglacial Lake Whillans, Antarctica, Alicia Marie Purcell
Diversity And Function Of Sulfur Cycling Microorganisms In Sediments From Subglacial Lake Whillans, Antarctica, Alicia Marie Purcell
Masters Theses
There is a growing consensus that metabolically and phylogenetically diverse assemblages of microorganisms mediate subglacial nutrient and elemental cycling. Subglacial Lake Whillans (SLW), located under 801 m of glacial ice, was recently penetrated using environmentally clean protocols. SLW is a permanently dark, cold (-0.5 °C [degrees Celsius]), and shallow (~2.2 m) freshwater lake beneath the West Antarctic Ice Sheet. The presence and diversity of key functional genes involved in dissimilatory sulfur oxidation and reduction were examined at various depths in two sediment cores taken from SLW. Our data show a diversity of sulfur transformation genes throughout the top 34 cm …
Diversity And Activity Of Roseobacters And Roseophage, Charles Ryan Budinoff
Diversity And Activity Of Roseobacters And Roseophage, Charles Ryan Budinoff
Doctoral Dissertations
Bacteria of the Roseobacter lineage are dominant bacterioplankton in coastal systems and contribute significantly to secondary production in oceanic environments. Generalities of Roseobacter ecology, diversity, and distributions are known, but the intraspecific differences between species and their dynamics over short temporal periods is not well understood. Bacteriophage that infect Roseobacters (‘roseophage’) have the potential to shunt secondary production into the dissolved carbon pool and through the process of infection alter Roseobacter physiology. Despite their significance, little effort was made prior to the onset of this study to characterize roseophage. Using culture dependent and independent approaches, I describe the diversity and …