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Item Evolution and function of flavin-based electron bifurcation(Montana State University - Bozeman, College of Letters & Science, 2018) Poudel, Saroj; Chairperson, Graduate Committee: Eric Boyd; John W. Peters (co-chair); Eric C. Dunham, Melody R. Lindsay, Maximiliano J. Amenabar, Elizabeth M. Fones, Daniel R. Colman and Eric S. Boyd were co-authors of the article, 'Origin and evolution of flavin-based electron bifurcating enzymes' in the journal 'Frontiers in microbiology' which is contained within this thesis.; Amaya M. Garcia Costas was an author and Anne-Frances Miller, Gerrit J. Schut, Rhesa N. Ledbetter, Kathryn R. Fixen, Lance C. Seefeldt, Michael W. W. Adams, Caroline S. Harwood, Eric S. Boyd and John W. Peters were co-authors of the article, 'Defining electron bifurcation in the electron transferring flavoprotein family' in the journal 'Journal of bacteriology' which is contained within this thesis.; Daniel R. Colman was an author and Kathryn R. Fixen, Rhesa N. Ledbetter, Yanning Zheng, Natasha Pence, Lance C. Seefeldt, John W. Peters, Caroline S. Harwood and Eric S. Boyd, were co-authors of the article, 'Electron transfer to nitrogenase in different genomic and metabolic backgrouns' in the journal 'Journal of bacteriology' which is contained within this thesis.Anaerobic microorganisms live in energy limited environments with low nutrient fluxes. Thus, selection has likely acted on these cells to innovate mechanisms that improve the efficiency of anaerobic energy metabolism. In 2008, the process of flavin-based electron bifurcation (FBEB) was discovered and has since been shown to be a critical process that allows anaerobic cells to overcome thermodynamic barriers and to improve metabolic efficiency. FBEB enzymes catalyze the coupling of exergonic and endergonic oxidation--reduction reactions with the same electron donor to circumvent thermodynamic barriers and minimize free energy loss. To date, a total of 12 FBEB enzymes have been discovered that share common features that include the presence of protein-bound flavin, the proposed site of bifurcation, and the electron carrier ferredoxin. Due to its recent discovery, a comprehensive description of the natural history of bifurcating enzymes is lacking. In this thesis, we report the taxonomic and ecological distribution, functional diversity, and evolutionary history of bifurcating enzyme homologs in available complete genomes and environmental metagenomes. Moreover, we investigated the functional and ecological constraints that led to the emergence of FBEB enzymes. Bioinformatics analyses revealed that FBEB enzyme homologs were primarily detected in the genomes of anaerobes, including those of sulfate-reducers, acetogens, fermenters, and methanogens. Phylogenetic analyses of these enzyme homologs suggest that they were not a property of the Last Universal Common Ancestor of Archaea and Bacteria indicating that they are a more recent evolutionary innovation. Consistent with the role of these enzymes in the energy metabolism of anaerobes, FBEB homologs were enriched in metagenomes from subsurface environments relative to those from surface environments. In fact, the earliest evolving homologs of most bifurcating enzymes were detected in subsurface environments, including fluids from subsurface rock fractures and hydrothermal systems. Together, these data highlight the central role that FBEB played and continued to play in the energy metabolism of anaerobic microbial cells inhabiting subsurface environments.Item A tree museum for Chautauqua, Washington(Montana State University - Bozeman, 1991) Wilson, Samuel R. (Samuel Ramsey), 1818-; Chairperson, Graduate Committee: Clark E. LlewellynItem The design of a natural history museum near Billings, Montana(Montana State University - Bozeman, 1973) Devitt, John M.Item Fermentation and anaerobic decomposition in a hot spring microbial mat(Montana State University - Bozeman, College of Agriculture, 1984) Anderson, Karen LeighItem The private lives of scientists : revealing the human-side of science film(Montana State University - Bozeman, College of Arts & Architecture, 2008) Misztal, Stefanie Snioszek; Chairperson, Graduate Committee: Walter Metz.As a genre, science films have routinely dehumanized the scientists who appear in them, portraying these characters as simple, one-dimensional encyclopedias of knowledge, whose sole purpose is to relay facts and provide expert testimony in support of the filmmaker's agenda. These films fall short of their true potential when they neglect to present their subjects as complex, multidimensional human beings with fascinating stories, opinions, tragedies and comedies to share about their lives. As science filmmakers we should attempt to re-humanize the way science is portrayed on film by looking to examples like standpoint feminist theory, which advocates owning our particular, incomplete subjective-viewpoints, or 'standpoints' as a form of empowerment. Championed by scientist and feminist scholar Donna Haraway, these partial perspectives allow filmmakers to create a place where the public and private lives of scientists can not only co-exist, but also strengthen one another. By exploring the complex world in the private lives of scientists, we can give greater respect to scientists themselves as well as to the intelligence and emotional needs of the greater public. To treat science and the people involved in its construction with more ethical responsibility, to build a more empowered and enlightened public, we as filmmakers need to introduce the personal values of willing scientists into the public sphere. If we can reinvent the science film as an endeavor steeped in humanity, it may become a more ethical and effective communication tool to fill these growing needs.Item Animals and artifacts : specimen exchanges and displays in Yellowstone National Park, The National Museum, and The National Zoo, 1846 to 1916(Montana State University - Bozeman, College of Letters & Science, 2012) Smith, Diane Marie; Chairperson, Graduate Committee: Mary Murphy.While much has been written about Yellowstone National Park, few historians have discussed the history of its wildlife, particularly before 1916 when the National Park Service was established. "Animals and Artifacts" investigates how Yellowstone came to be identified as wildlife's last refuge in the American West while also trying to understand how the U. S. Cavalry concurrently trapped and shipped animals to the National Zoological Park and, eventually, to zoos around the country. It also questions how animal displays and exchanges came to be so integral to the Park's administration, overall mission, and national identity during these formative years. This study relies on primary documents from the National Park Service and the Smithsonian Institution, including annual reports and correspondence dating from the establishment of the Smithsonian in 1846 until 1916 when the cavalry turned administration of the Park over to civilian control. Additional sources, including publications and newspapers from the period, were also consulted, as were secondary sources as appropriate. The research documents that the Smithsonian Institution, with its own well-established culture of specimen exchange initiated during its earliest years, viewed Yellowstone National Park as a primary source of specimens. In particular, it looked to the Park for animals of the American West, both living and dead, to display in Washington, D. C., entering excess specimens into its network of exchange. This special relationship helped define Yellowstone National Park's development and eventually transformed it into a center of animal displays. To understand how Yellowstone managers still haze animals back into the Park today requires a better understanding of how tourists, military administrators, and Smithsonian scientists alike all looked to Yellowstone to protect the wildlife of the American West while also expecting to see those animals on display. "Animals and Artifacts" looks at the early history of Yellowstone to better understand how this all came to pass.Item Reflexive filmmaking for wildlife and nature films(Montana State University - Bozeman, College of Arts & Architecture, 2009) Hiemenz, Vanessa Serrao; Chairperson, Graduate Committee: Ronald Tobias.Historically, wildlife and nature filmmakers have embraced the expository mode of filmmaking and a realistic style, attempting to influence their audience with compelling arguments. However, while their scripts may call for activism, their expository, realistic style, with hidden production methods, an authoritative tone, and pristine visuals, instead encourages voyeurism. In addition, standard theater and television distribution methods offer no outlet for action to viewers who do feel inspired. I offer a different model for influence in my wildlife series Nature Break: reflexive filmmaking. In this series I use such reflexive strategies to critique the voyeuristic way in which spectators consume wildlife and nature films. However, critiquing passive spectators with reflexivity is not the same as creating active spectators. Therefore, with Nature Break I go beyond simply making and distributing a film. Additionally, I will create a related website on the Internet as a platform for viewers to post their own films, discuss issues inspired by films on the site, and coordinate activism efforts. Through Internet distribution, the Nature Break series can finally live up to the reflexive filmmaker's goal of creating an art that leads to activism.