Life Sciences Commons^™

Characterizing The Quorum Sensing (Qs) System In The Model Eukaryote Chlamydomonas Reinhardtii, Kirstin Donnette Cutshaw

Theses and Dissertations

Group behaviors in microorganisms are often regulated by low-molecular weight molecules that enable them to sense population density, a signaling system known as quorum sensing (QS). QS in prokaryotes has provided insight into the role ‘social’ behaviors play in the bacterial world and refined our models of virulence, bacterial motility, and more. While less common, similar behaviors are observed in certain fungi, primarily yeasts, in which QS controls cell morphology, biofilm production, and other phenotypes. We have recently pursued the potential for QS to be more broadly distributed among unicellular eukaryotes, which could significantly alter our understanding of social behaviors …

Ammonium Chemotaxis In Chlamydomonas Reinhardtii, Gabela Nelson

LSU Doctoral Dissertations

Analysis of ammonium chemotaxis in Chlamydomonas reinhardtii is largely hindered, compared to that of phototaxis, despite equal importance on flagellated microalgal physiology. A major contribution of this shortfall is the lack of proper assay method. We developed a simple Petri dish assay method in which light is homogenously exposed while patterns of the cellular migration are tracked with a function of time. Using the method, new findings were revealed. First, this research presented that a strain lacking the eyespot organelle required for light gradient-sensing exhibits similar chemotactic behavior compared to a wild-type strain, suggesting Chlamydomonas sense an ammonium gradient not …

Tardigrade Niche Partitioning, Samantha Hougaard, Byron Adams

Library/Life Sciences Undergraduate Poster Competition 2024

The two types of Tardigrade (also known as Tardigrade), Ramazzottius and Echiniscus, coexist in the same environment. It could be assumed that they partition their resources by food type to avoid competition. To test this theory, I limited the two tardigrade groups to one food source.

C. Compactum Acts As A Comprehensive Climate Archive And Ecological Foundation In The Labrador Sea, Sadie Heckman

CMC Senior Theses

Clathromorphum compactum, a species of crustose coralline algae (CCA), is incredibly valuable for the future of high latitude ocean health, both as a comprehensive archive of changing ocean conditions, and ecologically as a foundational species for promoting biodiversity. Previous work establishes C. compactum as an effective climate proxy, and its life history provides several advantages for this use. C. compactum grow in nongeniculate, generally radial formations on hard substrates, over a wide distribution in mid-to-high latitude oceans and at subtidal depth ranges. Indeterminate growth leads to extreme longevity in C. compactum (Halfar et al., 2008), and growth rates are relatively …

The Nature And Extent Of Algal Symbiosis In Three North American Ranids, Zachary T. Vegso

Cal Poly Humboldt theses and projects

The symbiotic relationship between the chlamydomonad green alga Oophila amblystomatis and embryos of certain amphibian species is often presumed to be mutualistic. However, the existence of a mutualism has only been experimentally tested and established in two closely related ambystomatid salamanders. These experiments showed a positive correlation between intracapsular algal density and embryonic growth, survival, hatching synchrony, and hatchling body size. Oophila has been documented within egg capsules of a growing number of amphibian species, including several frogs in the family Ranidae. However, the nature and extent of this relationship remains unclear. Ranid eggs are better oxygenated than ambystomatid eggs, …

The Impacts Of Anthropogenic Activity And Climate Change On The Formation Of Harmful Algal Blooms (Habs) And Its Ecological Consequence, Zhangxi Hu, Aifeng Li, Zhun Li, Margaret R. Mulholland

OES Faculty Publications

No abstract provided.

Quantifying Wastewater Contributions To The Upper Clark Fork River, Claire Utzman

Graduate Student Theses, Dissertations, & Professional Papers

Though algae are at the base of food webs in many rivers, large algal blooms are increasing in frequency and can cause problems with nutrient cycling, depletion of oxygen supplies at night, and release of toxic chemicals. One leading cause of algal blooms is nutrient loading into rivers, and controlling nutrient release in wastewater is one approach that can help limit algal growth. To reduce the intensity of algal blooms in the Clark Fork River in western Montana, numeric nutrient standards were put in place that regulated the release of the nutrients nitrogen and phosphorus into the river from wastewater. …

Organic Carbon Decay Mediated By Mesopelagic Microbial Communities, Noah Jonathan Craft

OES Theses and Dissertations

Substantial remineralization of organic carbon occurs in the mesopelagic zone (i.e., the biological pump), the efficiency of which is responsible for the oceans’ capacity to store carbon originally derived from the atmosphere. To better understand how a substrate’s composition influences its degradation by mesopelagic microbial communities, we added treatments made of live algal cells, dead particulate organic carbon and dissolved organic carbon from ¹⁴C-labeled algal cultures to mesopelagic water collected in-situ. Each incubation took place in the laboratory over a period of months, during which PO¹⁴C, DO¹⁴C, ATP, prokaryote abundances and biochemical fractions were measured. …

Investigating The Phytotoxic Impacts Of Next-Generation Lithiated Cobalt Oxide Nanomaterials, Eric D. Ostovich

Theses and Dissertations

Lithium cobalt oxide nanosheets (LCO) are a type of next-generation transition metal oxide (TMO) nanomaterial and are one of the most commonly used cathode materials utilized in Li-ion batteries (LIB’s). With rapidly growing popularity of LIB’s as an energy storage technology, many consumer electronics and high-end electric vehicles have begun to incorporate these LIB’s into their design. And thus, the manufacturing rate of this nanomaterial has also skyrocketed to levels of environmental significance. However, despite its high levels of production, there is still little means for proper disposal of this nanomaterial, thus resulting in a highly probable environmental release. As …

Advances In Phaeodactylum Tricornutum Nuclear Engineering, Mark Pampuch

Electronic Thesis and Dissertation Repository

The marine diatom Phaeodactylum tricornutum has the potential to become an excellent platform for the sustainable production of valuable compounds and pharmaceuticals, but currently large-scale engineering of this organism remains a challenge due factors like inefficient genetic transformation protocols and a lack of accurate genomic data. This thesis addresses these two bottlenecks by (i) optimizing an electroporation protocol to P. tricornutum and (ii) remapping genomic data from a scaffolded genome assembly to a telomere-to-telomere genome assembly. An optimized transformation protocol was developed that could consistently transform blunt-ended and DNA with overhangs and yielded up to 1000+ colony forming units per …

Diversity, Function, And Phenotypic Plasticity Of Cryptophyte Phycobiliproteins, Kristiaän Merritt

Theses and Dissertations

Cryptophytes are a group of unicellular eukaryotic algae that can be found in a wide range of underwater habitats. Part of their ecological success can be attributed to their diverse array of cryptophyte phycobiliproteins (Cr-PBPs), a pigment class that captures wavelengths of light that are poorly absorbed by chlorophylls. Cryptophytes gained photosynthesis via secondary endosymbiosis in which their ancestor engulfed a red algal endosymbiont. Following endosymbiosis, they deconstructed the red algal photosynthetic machinery to form the Cr-PBP. Since then, the Cr-PBPs have diversified into at least 9 spectrally distinct forms. I investigated the diversity of Cr-PBP light absorption across 76 …

The Effect Of Algal Wastewater Treatment Systems On Microbial Communities, Alexis Leach

University Honors Program Senior Projects

In collaboration with the Metropolitan Water Reclamation District of Greater Chicago and Gross-Wen Technologies, I examined the microbial communities in experimental tertiary wastewater treatment systems employing algal phytoremediation. Three algal phytoremediation systems were examined: two vertical conveyor belt systems, known as the 10-foot belt system and the series 4 system, and a third system lacking a converter belt in which planktonic algae grew in a control pond. I used EcoPlates to measure carbon substrate utilization by microorganisms in each system. EcoPlates contain thirty-one different carbon substrates, with a dye that indicates microbial use of each substrate. I conducted a Principal …

Ecology, Evolution, And Gene Transfer Between Diatoms And Bacteria, Cory B. Gargas

Graduate Theses and Dissertations

Although photosynthetic macro-eukaryotes (i.e., plants) make up the majority of organic biomass on earth, bacteria are the second largest taxonomic group, by biomass. Bacteria are ubiquitous in our environment, living on, and within, man-made surfaces, natural environments, and eukaryotes themselves. The relationship between bacteria and eukaryotes has existed from the very beginning of eukaryotic life in the form of bacterial endosymbioses that resulted in mitochondria and plastids. Other eukaryote–bacteria relationships have evolved since then, ranging from the beneficial (e.g., mutualistic) to harmful (e.g., parasitic or pathogenic). Understanding these eukaryote–bacteria relationships is key to understanding both the evolution of important ecosystem …

Genetic Tools Towards A Synthetic Biology Approach For Whole Mitochondrial Genome Engineering, Ryan R. Cochrane

Electronic Thesis and Dissertation Repository

Synthetic biology is an interdisciplinary research field that standardizes and repurposes biological components to better understand life and solve complex problems. As synthetic biology has developed, the goal has become to generate fully controllable biological systems through whole genome engineering (WGE), the cumulation of standardized genome engineering, and DNA delivery methods. In eukaryotes, genetic tools for WGE are limited to the nucleus and present a need to expand to include mitochondria, which maintains its own unique genome. The work presented here begins developing the resources needed to enable whole mitochondrial genome engineering.

First, to standardize mitochondrial genome engineering protocols, I …

Structuring Life After Death: Plant Leachates Promote Co2 Uptake By Regulating Microbial Biofilm Interactions In A Northern Peatland Ecosystem, Allison R. Rober, Allyson J. Lankford, Evan Kane, Merritt R. Turetsky, Kevin H. Wyatt

Michigan Tech Publications

Shifts in plant functional groups associated with climate change have the potential to influence peatland carbon storage by altering the amount and composition of organic matter available to aquatic microbial biofilms. The goal of this study was to evaluate the potential for plant subsidies to regulate ecosystem carbon flux (CO2) by governing the relative proportion of primary producers (microalgae) and heterotrophic decomposers (heterotrophic bacteria) during aquatic biofilm development in an Alaskan fen. We evaluated biofilm composition and CO2 flux inside mesocosms with and without nutrients (both nitrogen and phosphorus), organic carbon (glucose), and leachates from common peatland plants (moss, sedge, …

Seasonal Starch Allocation In Starry Stonewort (Nitellopsis Obtusa) Harvested From Lake Koronis, Mn, And Development Of Non-Chemical Management Recommendations, Alyssa M. Haram

All Graduate Theses, Dissertations, and Other Capstone Projects

Starry stonewort (Nitellopsis obtusa) (Desvaux in Loiseleur) J. Groves is an invasive macro alga that can take over entire water columns and outcompete native species. Previous research has quantified seasonal life history and phenology but there is no research quantifying carbohydrate allocation which was the aim for Chapter II. Management efforts to control Nitellopsis obtusa have been limited to stressing the thalli and have not been able to directly target the reproductive bulbils on larger scales. Smaller scale efforts such as the use of hand pulling can be used but hand pulling is not realistic for larger infestations. Chapter III …

Early-Phase Drive To The Precursor Pool: Chloroviruses Dive Into The Deep End Of Nucleotide Metabolism, David Dunigan, Irina Agarkova, Ahmed Esmael, Sophie Alvarez, James L. Van Etten

Nebraska Center for Virology: Faculty Publications

Viruses face many challenges on their road to successful replication, and they meet those challenges by reprogramming the intracellular environment. Two major issues challenging Paramecium bursaria chlorella virus 1 (PBCV-1, genus Chlorovirus, family Phycodnaviridae) at the level of DNA replication are (i) the host cell has a DNA G+C content of 66%, while the virus is 40%; and (ii) the initial quantity of DNA in the haploid host cell is approximately 50 fg, yet the virus will make approximately 350 fg of DNA within hours of infection to produce approximately 1000 virions per cell. Thus, the quality and quantity of …

Phytoplankton Thermal Trait Parameterization Alters Community Structure And Biogeochemical Processes In A Modeled Ocean, Stephanie I. Anderson, Clara Fronda, Andrew D. Barton, Sophie Clayton, Tatiana A. Rynearson, Stephanie Dutkiewicz

OES Faculty Publications

Phytoplankton exhibit diverse physiological responses to temperature which influence their fitness in the environment and consequently alter their community structure. Here, we explored the sensitivity of phytoplankton community structure to thermal response parameterization in a modelled marine phytoplankton community. Using published empirical data, we evaluated the maximum thermal growth rates (μ_max) and temperature coefficients (Q₁₀; the rate at which growth scales with temperature) of six key Phytoplankton Functional Types (PFTs): coccolithophores, cyanobacteria, diatoms, diazotrophs, dinoflagellates, and green algae. Following three well-documented methods, PFTs were either assumed to have (1) the same μ_max and …

Sustainability Practices In Aquaculture: Using Algae Turf Scrubber Biomass To Raise Black Soldier Flies As An Alternative Feed In Blue Tilapia, Oreochromis Aureus, Culture, Michelle C. Lowery

Electronic Theses and Dissertations

Since the 1980s, non-algal aquaculture has grown to encompass 49% of all seafood production in response to a growing human population and increased seafood demand (FAO, 2022). Hurdles exist to aquaculture sustainability, including dependence on wild sourced fishmeal (FM) and the impacts wastewater discharge. It takes 4-5 tons of wild forage fish to produce one ton of dry FM (Miles and Chapman, 2006) and as aquaculture is primarily conducted in earthen ponds and public open water bodies (FAO, 2022), finfish culture can have a high impact on the surrounding environment by discharging excess nutrients. This study used algae turf scrubber …

Reflections On A Career Unplanned, Robert A. Glazer

Gulf and Caribbean Research

Sometimes life takes unexpected turns. I never planned to be a marine biologist; yet, after a long and unpredictable journey, that’s exactly where I found myself. After obtaining my B.S. in Fishery Biology from Colorado State University, I found myself meandering from job to job like a golden retriever following some vague scent. At first, I was hired by the Wyoming Game and Fish Department to work seasonally in Grand Teton National Park on the freshwater trout fisheries. Soon thereafter, I found myself cultivating oysters, clams, and other shellfish in California. The skills I developed there as an algologist led …

Dynamics Of Co2 Consumption, And Biomass And Lipid Carbon Production During Photobioreactor Cultivation Of The Diatom Cyclotella, Altan Özkan

Turkish Journal of Botany

Understanding of CO₂ delivery and consumption dynamics in algal photobioreactors are critical to unravel microalgae?s full potential for bioproduct generation and carbon capture from flue gas streams. This study aims to expand our current understanding by cultivating the diatom Cyclotella under controlled process conditions of a bubble column photobioreactor and analyzing CO₂ consumption dynamics in real time using results from an online CO₂ sensor connected to the reactor exhaust. Two sets of experiments were conducted: they served to contrast the influence of silicon and nitrate (Si&N colimitation) and Si limitation, and the light availability, respectively. CO2 consumption …

The Toxicity Of Dopamine On Salish Sea Phytoplankton, Allyson Lombardo

WWU Graduate School Collection

In the Salish Sea, blooms of the intertidal macroalgae, Ulvaria obscura, are common and can achieve extraordinarily high biomass. Upon desiccation and subsequent rehydration from incoming tides, U. obscura releases dopamine. Previous studies showed that dopamine negatively affects other macroalgal species and can deter grazers. However, the effects of dopamine on co-occurring phytoplankton remains unknown. This study explored the toxicity of dopamine on four phytoplankton known to inhabit the Salish Sea: the haptophyte, Isochrysis galbana; the chlorophyte, Dunaliella tertiolecta; the dinoflagellate, Heterocapsa triquetra; and the diatom, Thalassiosira sp. Over the course of 8 days, phytoplankton growth …

Clay As A Control Technique For Karenia Brevis: Water Chemistry Dynamics And Physiological Impacts On Benthic Invertebrates, Victoria Devillier

Graduate Thesis and Dissertation 2023-2024

Clay-based compounds are globally the most advanced and widely used method of direct suppression of marine harmful algal blooms, and are currently undergoing investigation as an option to control Karenia brevis blooms in Florida. Before clay may be accepted for widespread use, there are multiple concerns and challenges that must be addressed regarding the environmental safety of this method, such as effects on water quality, the fate of toxins, and potential impacts of clay treatment to non-target organisms. To contribute to ongoing assessments of clay as a potential control method for K. brevis blooms, we conducted experiments with a formulation …

Differential Expression Of Photosynthetic Genes In Cryptophyte Algae (Hemiselmis Cryptochromatica Ccmp 1181), Chastity D. Aguilar

Biology Theses

Cryptophytes are a group of freshwater algae that have acquired photosynthesis through secondary endosymbiosis with a red alga and an unknown eukaryote heterotroph. Cryptophytes possess photosynthetic pigment-protein structures called phycobiliproteins (PBPs). Cryptophyte phycobiliproteins are composed of α and β-protein subunits and four chromophores (bilins). There are nine classes of cryptophyte PBPs that absorb different wavelengths of light based on the type of bilins covalently bound to the protein subunits. Three cryptophyte PBPs are phycoerythrins that give the algae a red appearance and six are phycocyanins that give the algae a blue to green appearance. Hemiselmis cryptochromatica (CCMP 1181) is a …

The Effect Of Spirulina Platensis Algae Inclusion In Feed Of Commercial Broilers Subjected To Cyclic Heat Stress, Kirsten Shafer

Graduate Theses and Dissertations

The effect of Spirulina platensis inclusion in feed of commercial broilers was evaluated over one experiment. The study aimed to investigate the effects of Spirulina platensis freshwater algae inclusion on live performance and processing characteristics of commercial broilers subjected to daily cyclic heat stress. Day old Ross 708 male broilers were placed into 8 environmentally controlled chambers. At d 21, four chambers remained on a control diet containing no algae (CON) while 4 chambers received a diet that included algae at an inclusion rate of 2.5% (ALG). An 8 hour daily cyclic heat stress (24°C to 36°C) was applied to …

Nutrient Recovery From Wastewater By A Consortium Of Algae Species For Biofuel Production, Edgardo Ayala

Boise State University Theses and Dissertations

Current energy sources are predominantly petroleum-based and their use increases greenhouse gas (GHG) emissions. As the global population grows, and along with it the demand for energy, there is a need to further develop renewable energy sources to avoid the effects of increasing atmospheric CO₂ concentrations on the climate. Biofuels, a renewable energy source, have gained significant interest as a replacement for petroleum-based fuels due to their environmental benefits and carbon neutrality. Biofuels are expected to make up 9.0% of the total fuel consumption in the U.S. by 2040, up from 7.3% in 2019 [1]. Currently, terrestrial crop-based biofuels …

Turning Algal Biomass Waste Into A Sustainable Substrate For Oyster Settlement, Ariana Liezl M. Lipat

Honors College Theses

When an aquatic ecosystem becomes oversaturated with nutrients, algae in the water utilize the excess nitrogen and phosphorus present and grow uncontrollably. This creates algal blooms on the surface of the water that deplete oxygen levels in the water and kill numerous organisms in the process. One method used to solve this issue is through Algal Turf Scrubber (ATS) technology: a natural wastewater treatment process in which water polluted with excess nitrogen and phosphorus is pumped across a floway to be absorbed by a culture of algae before it flows out of the system. The algal biomass is harvested periodically …

Impacts Of Algal Morphology And Water Flow On Macroalgal Microplastic Capture, Cheyenne M. Adams

Honors College Theses

Microplastic pollution is a major area of concern in marine environments, especially as microplastics enter the food web. This study used pipe cleaners and two lichen species as algal mimics, and Chaetomorpha sp. and Chondrus crispus as model algal species to test the effects of morphology and biomass on microbead and foam capture. This study also utilized two different water flow methods: vortices and waves. Results suggest that water flow, as well as biomass and morphology, play a role in microplastic capture in macroalgae. For all mimics and algal species, except Cladonia lichens, turfs with increased biomass and length showed …

Alga Of My Eye, Determining The Ability Of Palmaria Palmata To Bioaccumulate Metals, Cameron Smith

WWU Honors College Senior Projects

Algae, specifically macroalgae, have rapidly sprung into the spotlight as a valuable natural resource to serve many functions in recent years. Individual community members and foragers have found algae useful for home cooking and garden fertilizer; it can also be used commercially in dietary supplements, cosmetics, pharmaceuticals, and animal feed. P. palmata is a red algal species that grows naturally in Northwestern Europe and Iceland and is commercially grown in Japan, Maine, and recently, California and Washington. This study aimed to investigate the ability of Palmaria palmata to bioaccumulate chromium, cadmium, lead, and zinc at eight different concentrations over 48 …

Filamentous Green Algae (Cladophora Glomerata) In Near Shore Lake Ontario: An Investigation Of Tissue And Water Nutrient Dynamics Through A Period Of Growth And Decomposition., James L. Wagner Jr

Biology Theses

Cladophora glomerata, a filamentous green alga abundant in the Laurentian Great Lakes, has long been considered a nuisance throughout the region. Previous phosphorus (P) abatement practices and legislation successfully reduced the abundance of the algae, but with the introduction of dreissenid mussels, a resurgence has been observed. Though there is substantial literature and modeling of the growth cycle of Cladophora, relatively little research has been dedicated to the decomposition stage of the algae, a period which may contribute to a substantial influx of nutrients to near-shore environmental regions. By first examining a period of in-situ growth within Lake …