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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 …
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 …
Genetic And Ecological Characterization Of Indigoidine Production By Phaeobacter Sp. Strain Y4i, William Nathan Cude
Genetic And Ecological Characterization Of Indigoidine Production By Phaeobacter Sp. Strain Y4i, William Nathan Cude
Doctoral Dissertations
The Roseobacter clade is a widely distributed, abundant, and biogeochemically active lineage of marine alpha-proteobacteria. Members of the Roseobacter lineage are prolific surface colonizers in marine coastal environments, and antimicrobial secondary metabolite production has been hypothesized to provide a competitive advantage in colonization. In this work, Phaeobacter sp. strain Y4I was found to produce the water soluble, blue pigment indigoidine via a nonribosomal peptide synthase-based biosynthetic pathway encoded by a novel series of genetically linked genes, termed igiBCDFE. Comparison of wildtype, non-pigmented, and hyper-pigmented Y4I insertional mutants demonstrated a perfect correlation between indigoidine production and the inhibition of Vibrio …
Validating Approaches For Studying Microbial Diversity To Characterize Communities From Roots Of Populus Deltoides, Migun Shakya
Validating Approaches For Studying Microbial Diversity To Characterize Communities From Roots Of Populus Deltoides, Migun Shakya
Doctoral Dissertations
Microbial (archaeal, bacterial, and fungal) communities associated with plant roots are central to its health, survival, and growth. However, a robust understanding of root microbiota and the factors that govern their community structure and dynamics have remained elusive, especially in mature perennial plants from natural settings. Although the advent of Next Generation Sequencing (NGS) technologies have changed the scale of microbial ecological studies by enabling exhaustive characterization of microbial communities, the accuracy of taxonomic and quantitative inferences are affected by multiple experimental and computational steps and lack of knowledge of the true ecological diversity. To test for inaccuracies and biases, …