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Full-Text Articles in Microbiology
Mechanisms For High Light Tolerance In A Fast-Growing Cyanobacterium, Patricia Walker
Mechanisms For High Light Tolerance In A Fast-Growing Cyanobacterium, Patricia Walker
Arts & Sciences Electronic Theses and Dissertations
Through oxygenic photosynthesis, cyanobacteria, algae, and plants convert light into chemical energy. However, highly energetic light often damages the photosynthetic apparatus, which can lead to the decline of photosynthetic activity (photoinhibition), and prolonged photoinhibition can lead to cell death. Cyanobacteria enact various protective mechanisms to mitigate photodamage, many of which have been conserved in plants. Repair of PSII reaction centers, decreased light absorption, quenching of excess absorbed energy, and biosynthesis of antioxidants all work to mitigate damage during high light. Due to the adjustments to photosynthesis, acclimation to high light requires remodeling of cellular metabolism and physiology. Therefore, phototrophs have …
Phylogenetic And Genomic Characterization Of The Host-Pathogen Arms Race Between Bacterial Pathogens And Gossypium Hirsutum, Anne Zimmerman Phillips
Phylogenetic And Genomic Characterization Of The Host-Pathogen Arms Race Between Bacterial Pathogens And Gossypium Hirsutum, Anne Zimmerman Phillips
Arts & Sciences Electronic Theses and Dissertations
Hosts and pathogens are eternally intertwined in an evolutionary arms race. When a pathogen causes a disease outbreak, scientists must identify resistance strategies that can durably tilt the arms race in favor of the host. This requires a deep understanding of both the genetic and environmental contexts in which the outbreak occurs. In this thesis I investigate the bacterial pathogens Xanthomonas citri pv. malvacearum (Xcm) and Pseudomonas syringae that caused disease outbreaks on Gossypium hirsutum from 2011-2017. I use pathogen genomics and host transcriptomics to develop hypotheses for how these pathogens emerged and how they cause disease. Phylogenetics and virulence …
Diverse Far-Red Light Utilization Strategies In Cyanobacteria And Algae, Benjamin Martin Wolf
Diverse Far-Red Light Utilization Strategies In Cyanobacteria And Algae, Benjamin Martin Wolf
Arts & Sciences Electronic Theses and Dissertations
In their natural environments, photosynthetic organisms are often exposed to widely varied light environments. Species adapted to shade light, often found growing in lower layers of photosynthetic biofilms, must survive on filtered light alone. Filtered light is highly enriched in far-red wavelengths, which are normally unavailable for photosynthetic energy production in most oxygenic phototrophs. To overcome light limitations in filtered light environments, some species of algae and cyanobacteria utilize specialized photosynthetic pigments and antenna systems to harvest these far-red wavelengths. By sampling the natural environment and using custom-built far-red light growth chambers, I have isolated several species of oxygenic phototrophs …