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Beyond Cortisol: Indicators Of Stress And Negative Feedback In Plasma And Blubber Of Marine Mammals, Jessica Avalos
Beyond Cortisol: Indicators Of Stress And Negative Feedback In Plasma And Blubber Of Marine Mammals, Jessica Avalos
University of the Pacific Theses and Dissertations
Marine mammals play an important role in ecosystem stability. However, anthropogenic activity is compounding pressure on many already vulnerable populations. A potential consequence of anthropogenic disturbance is physiological stress, which can impact metabolism, immunity, and reproduction, especially if it occurs repeatedly. Previous studies on marine mammals have focused on acute stress, but the impacts of repeated stress are poorly understood. Due to its accessibility on land during haul-outs, the northern elephant seal (Mirounga angustirostris) is a good system in which to study the effects of stress in marine mammals. Stress stimulates the release of glucocorticoid hormones, primarily cortisol. Elevated cortisol …
Inhibition Of Staphylococcus Aureus Biofilm By Variovorax Paradoxus, Esther Gomez
Inhibition Of Staphylococcus Aureus Biofilm By Variovorax Paradoxus, Esther Gomez
University of the Pacific Theses and Dissertations
Staphylococcus aureus is one of the leading causes of fatal nosocomial infections. Often, S. aureus can grow as a biofilm which protects the population from the surrounding environment. Strains of S. aureus are resistant to virtually all known antibiotics on the market. Variovorax paradoxus is a soil microbe with many unusual metabolic activities. It has been previously observed that, V. paradoxus can inhibit the growth of S. aureus when in co-culture. In this work we report on inhibition of S. aureus biofilm formation by V. paradoxus due to a suspected inhibitory soluble factor.
Impacts Of Plastic Pollution On A Pelagic Marine Mammal, The Northern Elephant Seal, Lauren M. Kashiwabara
Impacts Of Plastic Pollution On A Pelagic Marine Mammal, The Northern Elephant Seal, Lauren M. Kashiwabara
University of the Pacific Theses and Dissertations
As plastic pollution increases, top marine predators such as marine mammals are becoming increasingly susceptible to plastic particles and their additives. Plastic particles have been found in gastrointestinal tracts and scat of many marine mammals, and quantifying plastic pollution in those that are pelagic can provide insight into plastic pollution in mesopelagic ecosystems that are just beginning to be analyzed. Adapting well-developed laboratory techniques for microplastic (MP) isolation (i.e. density separation and chemical digestion), I isolated MPs from the scat of the deepest diving pinniped, the northern elephant seal (NES), and found that100% of scat samples (n=11) contained high counts …
Cpf1-Based Crispr Genome Editing In The Cyanobacterium N. Punctiforme, Soohan Woo
Cpf1-Based Crispr Genome Editing In The Cyanobacterium N. Punctiforme, Soohan Woo
University of the Pacific Theses and Dissertations
CRISPR systems have been growing in their utility and their application throughout the biological field as researchers continue to grow in their understanding of the relatively novel genome editing technology. However, despite the potential of CRISPR as a genome editing tool, the complexity of applying this technology to a specific organism calls for custom modifications to the system to improve its success rate. In this project, a CRISPR-Cpf1 system that can be effectively employed in the cyanobacterium Nostoc punctiforme was designed, with a focus on the hormogonium development of this species. Multiple plasmids containing the CRISPR system and targeting different …
Land-Use And Ant Biodiversity In California’S Central Valley, Laura L. Navarro
Land-Use And Ant Biodiversity In California’S Central Valley, Laura L. Navarro
University of the Pacific Theses and Dissertations
The growing human population results in growing demand for land allocated to urban development and agricultural production (Godfray et al. 2010; Tilman et al. 2011; McDonnell and Hahs 2013; Alexander et al. 2015; Erlwein and Pauleit 2021). Changes to land allocation associated with agricultural and urban development will increasingly alter terrestrial ecosystems impacting biodiversity (Ricketts et al. 2001; McDonald et al. 2008). Ants are an ideal organism for monitoring changes in biodiversity related to land-use change due to their ubiquitous nature, high diversity, and their role as bioindicators. The goal of this study was to assess the diversity of the …
The Bgs 13 Mutant Of Pichia Pastoris And Its Effect On Structural Changes Of The Reporter Protein B-Lactogolbulin, Bushra Irshad
The Bgs 13 Mutant Of Pichia Pastoris And Its Effect On Structural Changes Of The Reporter Protein B-Lactogolbulin, Bushra Irshad
University of the Pacific Theses and Dissertations
Pichia pastoris, a methylotrophic yeast, is an ideal host for recombinant protein expression. It has the capability of performing many eukaryotic post-translational modifications and grows to high cell densities. However, P. pastoris’s secretion properties are not always efficient, and its secretory pathway mechanisms have not been thoroughly elucidated. A previously identified mutant strain, bgs13, was found to efficiently secrete most recombinant proteins tested, raising the possibility that this bgs13 mutant is a universal super secreter and understanding its secretion process is needed. In this study, we used a reporter protein, ?-lactoglobulin (b-LG), to perform structural analysis and comparisons of protein …
How Do They Do It? Using Omics Approaches To Explore Metabolic Responses Associated With Hypoxia And Exercise Tolerance In The Deepest Diving Pinniped, Elizabeth R. Piotrowski
How Do They Do It? Using Omics Approaches To Explore Metabolic Responses Associated With Hypoxia And Exercise Tolerance In The Deepest Diving Pinniped, Elizabeth R. Piotrowski
University of the Pacific Theses and Dissertations
Marine mammals such as northern elephant seals (NES) routinely experience hypoxemia and ischemia-reperfusion events to many tissues during deep dives with no apparent adverse effects. Adaptations to diving include increased antioxidants and elevated oxygen storage capacity associated with high hemoprotein content in blood and muscle. Despite experiencing decreased oxygen tensions during diving, NES likely rely on the mobilization of large lipids stores and catabolism of fatty acids to provide energy to exercising muscle while diving. To identify potential regulatory mechanisms that may underly hypoxia and exercise tolerance in diving mammals, this study used system-wide approaches to characterize changes in genes …