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- All Subjects: conservation
- All Subjects: Microbiology
- Creators: School of Life Sciences
- Resource Type: Text
Description
Space microbiology, or the study of microorganisms in space, has significant applications for both human spaceflight and Earth-based medicine. This thesis traces the evolution of the field of space microbiology since its creation in 1935. Beginning with simple studies to determine if terrestrial life could survive spaceflight, the field of space microbiology has grown to encompass a substantial body of work that is now recognized as an essential component of NASA' research endeavors. Part one provides an overview of the early period of space microbiology, from high-altitude balloon and rocket studies to work conducted during the Apollo program. Part two summarizes the current state of the field, with a specific focus on the revolutionary contributions made by the Nickerson lab at the Biodesign Institute at ASU using the NASA-designed Rotating Wall Vessel (RWV) Bioreactor. Finally, part three highlights the research I've conducted in the Nickerson lab, as well as continuing studies within the field of space microbiology.
ContributorsMcCarthy, Breanne E. (Author) / Lynch, John (Thesis director) / Foy, Joseph (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
The Mexican gray wolf (Canis lupus baileyi) is a genetically distinct subspecies of the gray wolf (Canis lupus) that was driven to the brink of extinction as a result of human persecution. The wolf is listed as Endangered under the Endangered Species Act, and a recovery program is underway in Arizona and New Mexico to restore its population. However, the wolf is struggling to recover due to high mortality, which is a result of continued human hostility toward it. This thesis examines historical and current human attitudes toward the wolf and the implications that they have had on the extermination and recovery of the subspecies. An overview is given of wolf biology, the history of wolf extermination and recovery, and recent events relating to the recovery of the wolf. Negative impacts on ranching, hunting, and human safety are the main reasons for opposition toward wolves and wolf recovery; these concerns are analyzed, and solutions to them are proposed, with the goal of addressing them while fostering non-lethal coexistence with the wolf. In addition, opposition to wolves and wolf recovery is tied in with larger socio-political issues and is influenced by the representation of the wolf in culture; these issues in the context of wolves are also analyzed.
ContributorsLenk, Heather Nicole (Author) / Smith, Andrew (Thesis director) / Minteer, Ben (Committee member) / Brown, David E. (Committee member) / School of Life Sciences (Contributor) / School of Sustainability (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
Many bacteria actively import environmental DNA and incorporate it into their genomes. This behavior, referred to as transformation, has been described in many species from diverse taxonomic backgrounds. Transformation is expected to carry some selective advantages similar to those postulated for meiotic sex in eukaryotes. However, the accumulation of loss-of-function alleles at transformation loci and an increased mutational load from recombining with DNA from dead cells create additional costs to transformation. These costs have been shown to outweigh many of the benefits of recombination under a variety of likely parameters. We investigate an additional proposed benefit of sexual recombination, the Red Queen hypothesis, as it relates to bacterial transformation. Here we describe a computational model showing that host-pathogen coevolution may provide a large selective benefit to transformation and allow transforming cells to invade an environment dominated by otherwise equal non-transformers. Furthermore, we observe that host-pathogen dynamics cause the selection pressure on transformation to vary extensively in time, explaining the tight regulation and wide variety of rates observed in naturally competent bacteria. Host-pathogen dynamics may explain the evolution and maintenance of natural competence despite its associated costs.
ContributorsPalmer, Nathan David (Author) / Cartwright, Reed (Thesis director) / Wang, Xuan (Committee member) / Sievert, Chris (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Clean water for drinking, food preparation, and bathing is essential for astronaut health and safety during long duration habitation of the International Space Station (ISS), including future missions to Mars. Despite stringent water treatment and recycling efforts on the ISS, it is impossible to completely prevent microbial contamination of onboard water supplies. In this work, we used a spaceflight analogue culture system to better understand how the microgravity environment can influence the pathogenesis-related characteristics of Burkholderia cepacia complex (Bcc), an opportunistic pathogen previously recovered from the ISS water system. The results of the present study suggest that there may be important differences in how this pathogen can respond and adapt to spaceflight and other low fluid shear environments encountered during their natural life cycles. Future studies are aimed at understanding the underlying mechanisms responsible for these phenotypes.
ContributorsKang, Bianca Younseon (Author) / Nickerson, Cheryl (Thesis director) / Barrila, Jennifer (Committee member) / Ott, Mark (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Vaccinia virus (VV) is a prototype virus of the Orthopox viruses. The large dsDNA virus composed of 200kbp genome contains approximately 200 genes and replicates entirely in the cytosol. Since its use as a live vaccine against smallpox that leads to the successful eradication of smallpox, Vaccinia has been intensely studied as a vaccine vector since the large genome allows for the insertion of multiple genes. It is also studied as a molecular tool for gene therapy and gene functional study. Despite its success as a live vaccine, the vaccination causes some mild to serious bur rare adverse events in vaccinees such as generalized Vaccinia and encepharitis. Therefore, identification of virulence genes and removal of these genes to create a safer vaccine remain an important tasks. In this study, the author seeks to elucidate the possible relationship between immune evading proteins E3 and B19. VV did not allow double deletions of E3 and B19, indicating the existence of a relationship between the two genes.
ContributorsBarclay, Shizuka (Author) / Jacobs, Bertram (Thesis director) / Ugarova, Tatiana (Committee member) / Kibler, Karen (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
A literature review summarizing the current status of conservation efforts of the Mojave Desert tortoise (Gopherus agassizii) including a brief overview of the Endangered Species Act (ESA) and its applicability to this species' conservation. A genetic and physiological comparison of the morphologically similar Mojave species with the Sonoran (Gopherus morafkai) species proceeded by an analysis of if and how the ESA should apply to the Sonoran population. Analysis of current plans and interagency cooperations followed by a multi-step proposal on how best to conserve the Sonoran population of Desert tortoise.
ContributorsKulik, Elise Chikako (Author) / Kusumi, Kenro (Thesis director) / Tollis, Marc (Committee member) / Wilson Sayres, Melissa (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / School of Life Sciences (Contributor)
Created2015-05
Description
Birds have unusually high plasma glucose concentrations compared to mammals of similar size despite their high metabolic rate. While birds use lipids as their main source of energy, it is still unclear how and why they maintain high plasma glucose concentrations. To investigate a potential underlying mechanism, this study looks at the role of lipolysis in glucose homeostasis. The purpose of this study is to examine the effects of decreased glycerol availability (through inhibition of lipolysis) on plasma glucose concentrations in mourning doves. The hypothesis is that decreased availability of glycerol will result in decreased production of glucose through gluconeogenesis leading to reduced plasma glucose concentrations. In the morning of each experiment, mourning doves were collected at the Arizona State University Tempe campus, and randomized into either a control group (0.9% saline) or experimental group (acipimox, 50mg/kg BM). Blood samples were collected prior to treatment, and at 1, 2, and 3 hours post-treatment. At 3 hours, doves were euthanized, and tissue samples were collected for analysis. Acipimox treatment resulted in significant increases in blood glucose concentrations at 1 and 2 hours post- treatment as well as renal triglyceride concentrations at 3 hours post-treatment. Change in plasma free glycerol between 0h and 3h followed an increasing trend for the acipimox treated animals, and a decreasing trend in the saline treated animals. These results do not support the hypothesis that inhibition of lipolysis should decrease blood glycerol and blood glucose levels. Rather, the effects of acipimox in glucose homeostasis appear to differ significantly between birds and mammals suggesting differing mechanisms for glucose homeostasis.
ContributorsKouteib, Soukaina (Author) / Sweazea, Karen (Thesis director) / Deviche, Pierre (Committee member) / Chandler, Douglas (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2015-05
Description
Renewable bioproduction through fermentation of microbial species such as E. coli shows much promise in comparison to conventional fossil fuel based chemical production. Although Escherichia coli is a workhorse for bioproduction, there are inherent limitations associated with the use of this organism which negatively affect bioproduction. One example is E. coli fermentative growth being less robust compared to some microbes such as Lactobacilli under anaerobic and microaerobic fermentation conditions. Identification and characterization of its fermentative growth constraints will help in making E. coli a better fermentation host. In this thesis, I demonstrate that Lactobacillus plantarum WCFS1 has desirable fermentative capabilities that may be transferrable to E. coli through genetic engineering to alleviate growth restraints. This has led to the hypothesis that these L. plantarum DNA sequences are transferrable through a genomic library. A background of comparative genomics and complementary literature review has demonstrated that E. coli growth may be hindered by stress from many toxin-antitoxin systems. L. plantarum WCFS1 optimizes amino acid catabolism over glycolysis to generate high ATP levels from reducing agents and proton motive force, and Lactobacilli are resistant to acidic environments and encodes a wide variety of acid transporters that could help E. coli fermentative growth. Since a great variety of L. plantarum genes may contribute to its fermentative capabilities, a gDNA library containing L. plantarum WCFS1 genes has been successfully constructed for testing in E. coli bioproducers to search for specific genes that may enhance E. coli fermentative performance and elucidate the molecular basis of Lactobacillus fermentative success.
ContributorsDufault, Matthew Elijah (Co-author, Co-author) / Wang, Xuan (Thesis director) / Nielsen, David (Committee member) / Varman, Arul (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Peatlands are a type of wetlands where the rate of accumulation of organic matter exceed the rate of decomposition and have accumulated more than 30 cm of peat (Joosten and Clark, 2002). Peatlands store approximately 30% of all terrestrial carbon as recalcitrant peat, partially decomposed plant and microbial biomass, while simultaneously producing almost 40% of the globally emitted methane (Schmidt et al., 2016), making peatlands an important component of the carbon budgets. Published research indicates that the efficiency of carbon usage among microbial communities can determine the soil-carbon response to rising temperatures (Allison et al. 2010). By determining carbon consumption in peatland soils, total community respiration response, and community structure change with additions, models of carbon use efficiency in permafrost peatlands will be well-informed and have a better understanding of how the peatlands will respond to, and utilize, increased availability of carbon compounds due to the melting permafrost. To do this, we will sequence Lutose deep core samples to observe baseline microbial community structure at different depths and different age-gradients, construct substrate incubations of glucose and propionate and observe community respiration response via a gas chromatography flame ionization detector, track the glucose and propionate additions with high-performance liquid chromatography (HPLC), and sequence the samples once more to determine if there was a deviation from the initial community structure obtained prior to the incubations. We found that our initial sequencing data was supported by previous work (Lin et al., 2014), however we were unable to sequence samples post-incubation due to time constraints. In this sequencing analysis we found that the strongest variable that made samples biologically similar was the age-gradient site in which they were extracted. We found that the group with glucose additions produced the most carbon dioxide compared with the other treatments, but was not the treatment that dominated the production of methane. Finally, in the HPLC samples that were analyzed, we found that glucose is likely forming the most by-product accumulation from mass balance calculations, while propionate is likely forming the least. Future experimentation should focus on the shortcomings of this experiment. Further analysis of 16S rRNA sequencing data from after the incubations should be analyzed to determine the change in microbial community structure throughout the experiment. Furthermore, HPLC analysis for the several samples need to be done and followed up with mass balance to determine where the added glucose and propionate are being allocated within the soil. Once these pieces of the puzzle are put into place, our original question of how the microbial community structure changes at different depths and age-gradients within permafrost peatlands will be conclusively answered.
ContributorsFrese, Alexander Nicholas (Author) / Cadillo-Quiroz, Hinsby (Thesis director) / van Paassen, Leon (Committee member) / Sarno, Analissa (Committee member) / School of Life Sciences (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
The International Union for Conservation of Nature's Red List of Threatened Species is the most comprehensive and objective global approach to evaluate the conservation status of species by categorizing species based on relative extinction risk. For the Global Muranidae IUCN Red List assessment, all known, taxonomically valid species of Muraenidae were assessed for their extinction risk using the IUCN Red List Global Categories and Criteria. Of all 208 Muraenidae species, it was concluded that 86% of species qualified for Least Concern, 13% of species are Data Deficient, and 1% of species qualified for a threatened category. Channomuraena bauchotae is listed as threatened under VU D2 and Gymnothorax parini qualified for VU B2ab(iii). This study will have brought the International Union for the Conservation of Nature one step closer to their goal of conducting Red List assessments of all the world's species(not including microorganisms). Future implications of this study may include future monitoring of key habitat areas and species or conducting further research to gain a more in depth understanding of the life history and threats to Muraenidae.
ContributorsLaurence, Paige Marie (Author) / Polidoro, Beth (Thesis director) / Ralph, Gina (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05