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Full-Text Articles in Life Sciences

Prochlorococcus Death By A Ubiquitous Zooplankton Filter Feeder, Avery E. Harman Jun 2024

Prochlorococcus Death By A Ubiquitous Zooplankton Filter Feeder, Avery E. Harman

University Honors Theses

Prochlorococcus is a globally abundant cyanobacterium that can help reveal the ecology of microorganisms in the ocean. Specifically, mortality by zooplankton such as appendicularians is globally important and Prochlorococcus can help reveal some of the choices made around feeding for this ubiquitous filter feeder. Two ecotypes of Prochlorococcus were introduced to appendicularians to determine if appendicularian feed selectively between these ecotypes. Further, a single ecotype of Prochlorococcus was fed to appendicularians over a variety of life stages to determine if retention rate changed with appendicularian life stage. My results reveal that there is no significant selection between the two Prochlorococcus …


Rainwater Harvesting Systems Metagenomics, Jade Riddle, Julia Parsons Apr 2024

Rainwater Harvesting Systems Metagenomics, Jade Riddle, Julia Parsons

Spring Showcase for Research and Creative Inquiry

Climate change induced water scarcity has led to an increasing interest in non-traditional water sources such as rainwater. However, there are lingering health and safety concerns due to the lack of research into the microbial communities contained within collection systems. To address this gap, water samples were collected from rain barrels around northern Virginia for microbial analysis. Each microbe within the sample has a unique genome subject to DNA testing. Environmental DNA was prepared from the collected water samples. To characterize the microbial community, both targeted sequencing and whole genome sequencing approaches were used. Using targeted sequencing of the 16s …


Sulfur Cycling Connects Microbiomes And Biogeochemistry In Deep-Sea Hydrothermal Plumes, Zhichao Zhou, Patricia Q. Tran, Alyssa M. Adams, Kristopher Kieft, John A. Breier, Caroline S. Fortunato, Cody S. Sheik, Julie A. Huber, Meng Li, Gregory J. Dick, Karthik Anantharaman Aug 2023

Sulfur Cycling Connects Microbiomes And Biogeochemistry In Deep-Sea Hydrothermal Plumes, Zhichao Zhou, Patricia Q. Tran, Alyssa M. Adams, Kristopher Kieft, John A. Breier, Caroline S. Fortunato, Cody S. Sheik, Julie A. Huber, Meng Li, Gregory J. Dick, Karthik Anantharaman

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

In globally distributed deep-sea hydrothermal vent plumes, microbiomes are shaped by the redox energy landscapes created by reduced hydrothermal vent fluids mixing with oxidized seawater. Plumes can disperse over thousands of kilometers and their characteristics are determined by geochemical sources from vents, e.g., hydrothermal inputs, nutrients, and trace metals. However, the impacts of plume biogeochemistry on the oceans are poorly constrained due to a lack of integrated understanding of microbiomes, population genetics, and geochemistry. Here, we use microbial genomes to understand links between biogeography, evolution, and metabolic connectivity, and elucidate their impacts on biogeochemical cycling in the deep sea. Using …


Opening The Black Box: Soil Microbial Communities In Field-Based Plant-Soil Feedback Experiments, Julia Kate Aaronson Aug 2023

Opening The Black Box: Soil Microbial Communities In Field-Based Plant-Soil Feedback Experiments, Julia Kate Aaronson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Plant-soil feedback is a process through which plants modify the properties of their associated soils, affecting their growth. PSF can play a key role in regulating plant growth and communities including altering plant invasion, rarity, and abundance. However, our understanding of the soil organisms that drive these plant growth responses is limited. Most studies treat soils as a ‘black box’ and do little to reveal which specific microbes or microbial communities may be responsible. This chapter examines two recent large PSF field experiments conducted in Minnesota, USA, and Jena, Germany. These experiments revealed that plants altered their soils, changing subsequent …


Deconstructed Plastic Substrate Preferences Of Microbial Populations From The Natural Environment, Lindsay I. Putman, Laura G. Schaerer, Ruochen Wu, Daniel G. Kulas, Ali Zolghadr, Rebecca Ong, David Shonnard, Stephen Techtmann Jun 2023

Deconstructed Plastic Substrate Preferences Of Microbial Populations From The Natural Environment, Lindsay I. Putman, Laura G. Schaerer, Ruochen Wu, Daniel G. Kulas, Ali Zolghadr, Rebecca Ong, David Shonnard, Stephen Techtmann

Michigan Tech Publications

Over half of the world's plastic waste is landfilled, where it is estimated to take hundreds of years to degrade. Given the continued use and disposal of plastic products, it is vital that we develop fast and effective ways to utilize plastic waste. Here, we explore the potential of tandem chemical and biological processing to process various plastics quickly and effectively. Four samples of compost or sediment were used to set up enrichment cultures grown on mixtures of compounds, including disodium terephthalate and terephthalic acid (monomers of polyethylene terephthalate), compounds derived from the chemical deconstruction of polycarbonate, and pyrolysis oil …


Characterization Of A Novel Polyextremotolerant Fungus, Exophiala Viscosa, With Insights Into Its Melanin Regulation And Ecological Niche, Erin C. Carr, Quin Barton, Sarah Grambo, Mitchell Sullivan, Cecile M. Renfro, Alan Kuo, Jasmyn Pangilinan, Anna Lipzen, Keykhosrow Keymanesh, Emily Savage, Kerrie Barry, Igor V. Grigoriev, Wayne R. Riekhof, Steven D. Harris May 2023

Characterization Of A Novel Polyextremotolerant Fungus, Exophiala Viscosa, With Insights Into Its Melanin Regulation And Ecological Niche, Erin C. Carr, Quin Barton, Sarah Grambo, Mitchell Sullivan, Cecile M. Renfro, Alan Kuo, Jasmyn Pangilinan, Anna Lipzen, Keykhosrow Keymanesh, Emily Savage, Kerrie Barry, Igor V. Grigoriev, Wayne R. Riekhof, Steven D. Harris

School of Biological Sciences: Faculty Publications

Black yeasts are polyextremotolerant fungi that contain high amounts of melanin in their cell wall and maintain a primar yeast form. These fungi grow in xeric, nutrient depletes environments which implies that they require highly flexible metabolisms and have been suggested to contain the ability to form lichen-like mutualisms with nearby algae and bacteria. However, the exact ecological niche and interactions between these fungi and their surrounding community are not well understood. We have isolated 2 novel black yeasts from the genus Exophiala that were recovered from dryland biological soil crusts. Despite notable differences in colony and cellular morphology, both …


Mechanistic Examination Of Protist-Mediated Plant Growth Through The Comparative Development Of Medicago Truncatula, Shane Connolly May 2023

Mechanistic Examination Of Protist-Mediated Plant Growth Through The Comparative Development Of Medicago Truncatula, Shane Connolly

University Scholar Projects

Protists are known to increase plant growth through two main mechanisms: the microbial loop and the alteration of the root microbiome. The microbial loop is a nutrient recycling method in which protists provide inorganic nitrogen ions to the plant. Alteration of root microbiome leads to the removal of plant pathogens and shifting communities towards plant growth-promoting bacteria (PGPB). This study aimed to elicit which mechanism could produce the largest boost in shoot weight for Medicago truncatula. A series of microcosm experiments were explored in which M. truncatula was grown with variable microbiome structures to allow for mechanism differentiation. The …


Diverse Marine T4-Like Cyanophage Communities Are Primarily Comprised Of Low-Abundance Species Including Species With Distinct Seasonal, Persistent, Occasional, Or Sporadic Dynamics, Emily Dart, Jed A. Fuhrman, Nathan A. Ahlgren Feb 2023

Diverse Marine T4-Like Cyanophage Communities Are Primarily Comprised Of Low-Abundance Species Including Species With Distinct Seasonal, Persistent, Occasional, Or Sporadic Dynamics, Emily Dart, Jed A. Fuhrman, Nathan A. Ahlgren

Biology

Cyanophages exert important top-down controls on their cyanobacteria hosts; however, concurrent analysis of both phage and host populations is needed to better assess phage-host interaction models. We analyzed picocyanobacteria Prochlorococcus and Synechococcus and T4-like cyanophage communities in Pacific Ocean surface waters using five years of monthly viral and cellular fraction metagenomes. Cyanophage communities contained thousands of mostly low-abundance (<2% relative abundance) species with varying temporal dynamics, categorized as seasonally recurring or non-seasonal and occurring persistently, occasionally, or sporadically (detected in ≥85%, 15-85%, or <15% of samples, respectively). Viromes contained mostly seasonal and persistent phages (~40% each), while cellular fraction metagenomes had mostly sporadic species (~50%), reflecting that these sample sets capture different steps of the infection cycle-virions from prior infections or within currently infected cells, respectively. Two groups of seasonal phages correlated to Synechococcus or Prochlorococcus were abundant in spring/summer or fall/winter, respectively. Cyanophages likely have a strong influence on the host community structure, as their communities explained up to 32% of host community variation. These results support how both seasonally recurrent and apparent stochastic processes, likely determined by host availability and different host-range strategies among phages, are critical to phage-host interactions and dynamics, consistent with both the Kill-the-Winner and the Bank models.


From The Organismal To Biosphere Levels: Environmental Impacts On The Amphibian Microbiota, Obed Hernandez-Gomez, Jessica Hua Feb 2023

From The Organismal To Biosphere Levels: Environmental Impacts On The Amphibian Microbiota, Obed Hernandez-Gomez, Jessica Hua

Natural Sciences and Mathematics | Faculty Scholarship

This review summarizes the role of environmental factors on amphibian microbiotas at the organismal, population, community, ecosystem, and biosphere levels. At the organismal-level, tissue source, disease status, and experimental manipulations were the strongest predictors of variation in amphibian microbiotas. At the population-level, habitat quality, disease status, and ancestry were commonly documented as drivers of microbiota turnover. At the community-level, studies focused on how species’ niche influence microbiota structure and function. At the ecosystem-level, abiotic and biotic reservoirs were important contributors to microbiota structure. At the biosphere-level, databases, sample banks, and semi-natural experiments were commonly used to describe microbiota assembly mechanisms …


Fine-Scale Genetic Structure In Rhizosphere Microbial Communities Associated With Chamaecrista Fasciculata (Fabaceae), Mahboubeh Hosseinalizadeh Nobarinezhad, Lisa E. Wallace Jan 2023

Fine-Scale Genetic Structure In Rhizosphere Microbial Communities Associated With Chamaecrista Fasciculata (Fabaceae), Mahboubeh Hosseinalizadeh Nobarinezhad, Lisa E. Wallace

Biological Sciences Faculty Publications

Soil microbiota of the rhizosphere are an important extension of the plant phenotype because they impact the health and fitness of host plants. The composition of these communities is expected to differ among host plants due to influence by host genotype. Given that many plant populations exhibit fine-scale genetic structure (SGS), associated microbial communities may also exhibit SGS. In this study, we tested this hypothesis using Chamaecrista fasciculata, a legume species that has previously been determined to have significant SGS. We collected genetic data from prokaryotic and fungal rhizosphere communities in association with 70 plants in an area of …


Community Ecology And Disease Dynamics In Pacific Oysters: Unraveling Microbiome-Pathogen Interactions In The Wild, Victoria E. Cifelli Jan 2023

Community Ecology And Disease Dynamics In Pacific Oysters: Unraveling Microbiome-Pathogen Interactions In The Wild, Victoria E. Cifelli

Cal Poly Humboldt theses and projects

In the context of multispecies microbial assemblages, disruptions can occur when there are alterations in host conditions, such as the onset of a disease. Notably, viruses have the potential to reshape a host's microbial community. However, the role of the host's habitat and environment, which could be pivotal in communities with shifting niche space and habitat filters, is often overlooked in host-microbe-pathogen interactions. Recognizing the importance of these factors, I employed a field-based approach to understand microbial community dynamics in the presence of disease. To address the influence of geographical location, I conducted an analysis involving healthy and infected oysters …


Host-Microbe Interactions In Non-Native Estuarine Anemones: Biogeography And Temperature, Parker K. Lund Jan 2023

Host-Microbe Interactions In Non-Native Estuarine Anemones: Biogeography And Temperature, Parker K. Lund

Cal Poly Humboldt theses and projects

Non-native species are increasing in prevalence around the world, resulting in negative economic and ecological impacts. However, the broad distributions of non-native species also offer a system for investigating the response of host-associated microbial communities to environmental factors across a range of ecological scales. At the broadest scale, I investigated the geography of microbial communities in the non-native estuarine anemone Diadumene lineata on the west coast of the United States of America. Across latitudes, microbial community composition was very similar and displayed a high percentage of Klebsiella spp. at all sites. However, the communities in California tended to exhibit higher …


Investigating The Effectiveness Of Microplastic Removal And The Relationship Between Microplastics, Bacterial Communities, And Nitrogen Cycling In The Natural Treatment Systems At The Arcata Wastewater Treatment Facility, Fiona Connor Jan 2023

Investigating The Effectiveness Of Microplastic Removal And The Relationship Between Microplastics, Bacterial Communities, And Nitrogen Cycling In The Natural Treatment Systems At The Arcata Wastewater Treatment Facility, Fiona Connor

Cal Poly Humboldt theses and projects

This thesis addressed two challenging aspects of microplastic research, including the quantification of microplastics in organic-rich water, and the investigation of how microplastics impact microorganisms and related nutrient-cycling. Two projects were designed and executed to address specific research objectives relating to these broad topics. The first objective was to develop and implement methods to determine the effectiveness of microplastic removal across the natural treatment systems at the Arcata Wastewater Treatment Facility (AWTF). The second objective was to observe how microplastics found in domestic wastewater impact the bacterial communities and nitrogen cycling in freshwater treatment wetland sediment through a bench-scale experiment, …


Death Of A Bacterium: Exploring The Inhibition Of Staphylococcus Aureus By Burkholderia Cenocepacia., Tiffany Brandt Dec 2022

Death Of A Bacterium: Exploring The Inhibition Of Staphylococcus Aureus By Burkholderia Cenocepacia., Tiffany Brandt

Electronic Theses and Dissertations

Antimicrobial resistance is a phenomenon of increasing concern as antimicrobial overuse and misuse eliminate current therapeutic options, ushering society into a post-antimicrobial era. Antibiotic discovery and synthesis efforts are urgently needed to counter the increasing burden of antimicrobial resistance. Staphylococcus aureus is a causative agent of a variety of clinical manifestations including bacteremia, endocarditis, soft tissue infection, osteomyelitis, and device-related infections. S. aureus infection presents additional treatment challenges due to its capacity for biofilm formation, which is a mode of growth that confers protection from antibiotics and physical elimination, and the emergence of antibiotic resistant strains, including methicillin-resistant S. aureus …


Microbiome Diversity And Metabolic Capacity Determines The Trophic Ecology Of The Holobiont In Caribbean Sponges, Michael P. Lesser, M. Sabrina Pankey, Marc Slattery, Keir J. Macartney, Deborah J. Gochfeld Nov 2022

Microbiome Diversity And Metabolic Capacity Determines The Trophic Ecology Of The Holobiont In Caribbean Sponges, Michael P. Lesser, M. Sabrina Pankey, Marc Slattery, Keir J. Macartney, Deborah J. Gochfeld

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Sponges are increasingly recognized as an ecologically important taxon on coral reefs, representing significant biomass and biodiversity where sponges have replaced scleractinian corals. Most sponge species can be divided into two symbiotic states based on symbiont community structure and abundance (i.e., the microbiome), and are characterized as high microbial abundance (HMA) or low microbial abundance (LMA) sponges. Across the Caribbean, sponge species of the HMA or LMA symbiotic states differ in metabolic capacity, as well as their trophic ecology. A metagenetic analysis of symbiont 16 S rRNA and metagenomes showed that HMA sponge microbiomes are more functionally diverse than LMA …


Microbial Sociality In Biofilms, Swetha Kasetty May 2022

Microbial Sociality In Biofilms, Swetha Kasetty

Dartmouth College Ph.D Dissertations

Biofilms are communities of microorganisms attached to surfaces through various self-secreted matrix materials. Biofilms are dynamic communities with extensive interactions between their residents. Microorganisms compete, cooperate, and communicate with each other in biofilms. These ecological interactions determine the emergence or loss of strains/species and are critical in the formation and proliferation of biofilms. Furthermore, most natural biofilms are formed by multiple microbial species and strains and these interactions within the biofilm dramatically influence community composition and structure over time. Microbial interactions also influence clinically relevant outcomes such as antibiotic resistance and host virulence. In this thesis we explore the potential …


The Spatial, Temporal, And Ecological Constraints Of Plant-Host Associated Microbial Communities, Jonathan Dickey May 2022

The Spatial, Temporal, And Ecological Constraints Of Plant-Host Associated Microbial Communities, Jonathan Dickey

Doctoral Dissertations

With the development of next generation sequencing technology, ecologists have recently been able to describe microbial communities across a wide array of niches at an accelerated pace. De-novo-based patterns in richness and relative abundance have been described for bacterial and fungal communities in terrestrial, aquatic, and host-associated microhabitats. A recent synthesis has shown that these communities exhibit similar geographical patterns that have been traditionally described for plant and animals. Yet, there is a lack of hypothesis-based research for host-associated microbial communities. Throughout this dissertation, I will address how spatial scale, sequencing resolution, and manipulative rainfall exclusion govern host-associated microbial communities …


Making Sense Of Soil Microbiome Complexity For Plant And Ecosystem Function In A Changing World, Kendall K. Beals May 2022

Making Sense Of Soil Microbiome Complexity For Plant And Ecosystem Function In A Changing World, Kendall K. Beals

Doctoral Dissertations

Soils contain the highest biodiversity on Earth. While the importance of the soil microbiome for larger-scale ecological phenomena such as nutrient and carbon cycling, plant growth and plant community dynamics is well-established, the fundamental question of the ecological and evolutionary function of this immense belowground microbial diversity for plant and ecosystem function still remains a great challenge in microbial ecology research. The objective of this dissertation is to understand how the importance of soil microbial community composition for plant and ecosystem function and how changes to soil microbial community composition from climate change-induced disturbance events, specifically fire, influence plant and …


Microbial Community And Soil Responses To Land Management Practices In Remnant And Restored Tallgrass Prairies, Desirae Marie Klimek Jan 2022

Microbial Community And Soil Responses To Land Management Practices In Remnant And Restored Tallgrass Prairies, Desirae Marie Klimek

Graduate Research Theses & Dissertations

Critical ecosystem functions, such as decomposition and nutrient cycling, are driven by microbial communities within soil. As such, it is important to examine the effect of restoration practices, such as the presence of native grazers and prescribed burning, on these microbes and the soil they inhabit. The Nachusa Grasslands provides a chronosequence of restored tallgrass prairies ranging in restoration age from 5 to 33 years, as well as remnant prairies, and agricultural fields. These sites were sampled seasonally from 2013-2020 and microbial ribosomal RNA genes were surveyed to characterize soil microbial communities and assess how common restoration practices affect these …


Degradation And Nitrogen Cycling In The Context Of Biodiversity-Ecosystem Function Relationships In The Inquiline Bacterial Community Of Darlingtonia Californica, Megan Teigen Jan 2022

Degradation And Nitrogen Cycling In The Context Of Biodiversity-Ecosystem Function Relationships In The Inquiline Bacterial Community Of Darlingtonia Californica, Megan Teigen

Cal Poly Humboldt theses and projects

Biodiversity-ecosystem function (BEF) research aims to explain how species and their environments interact with each other. Microbial communities engage in vital biogeochemical pathways in a variety of natural ecosystems, and yet there are large knowledge gaps about the specific metabolic pathways in which they are involved. Degradation specifically contributes to nitrogen cycling globally through the breakdown of large organic nitrogen compounds into small inorganic nitrogen that is necessary for the survival of many other organisms. In this study, I focused on the degradative function of the inquiline microbial communities found within the carnivorous pitcher plant, Darlingtonia californica. Darlingtonia grows in …


Environmental Effects On Constructed Wetland Microbial Diversity And Function In The Context Of Wastewater Management, Sandrine Grandmont-Lemire Jan 2022

Environmental Effects On Constructed Wetland Microbial Diversity And Function In The Context Of Wastewater Management, Sandrine Grandmont-Lemire

Cal Poly Humboldt theses and projects

Microbial communities play a crucial role in ecosystems, yet we know little about how microbial diversity influences ecosystem functioning. An important gap in our understanding is how environmental change affects microbial Biodiversity-Ecosystem Function relationships (BEF). These complex interactions between microbial biodiversity and ecosystem function can influence major biogeochemical processes, such as the nitrogen cycle in wetland ecosystems, which play an important role in managing wastewater. To address the effect of biodiversity on function, my study investigates the BEF relationships between microbial diversity and the function in terms of ammonia removal from wastewater at the Arcata Wastewater Treatment Facility (AWTF) both …


Microbial Community Dynamics During Key Life History Transitions In The Deep-Sea Chemosymbiotic Mussel, Gigantidas Childressi, Tessa F. Beaver Jan 2022

Microbial Community Dynamics During Key Life History Transitions In The Deep-Sea Chemosymbiotic Mussel, Gigantidas Childressi, Tessa F. Beaver

WWU Graduate School Collection

Marine invertebrates form specific associations with bacterial communities that are different from their environment, change throughout their development, and shape evolutionary and ecological processes. The bathymodiolin (Mytilidae) mussel Gigantidas childressi lives at deep-sea methane seeps and relies on methanotrophic endosymbionts for its nutrition. Its larval life, however, is spent feeding in the water column. Upon metamorphosis at a suitable seep habitat, methanotrophic bacteria rapidly colonize gill cells and the juvenile mussel switches to symbiont-derived energy. To determine if the microbiome of the G. childressi changes during these transitions, the V3/V4 region of the 16S rRNA gene was sequenced to census …


Restricted Microbial Presence, Activity, And Community Structuring Within Dry Valley Soils Of Antarctica, Scott Fillerup George Dec 2021

Restricted Microbial Presence, Activity, And Community Structuring Within Dry Valley Soils Of Antarctica, Scott Fillerup George

Theses and Dissertations

The McMurdo Dry Valley region is the largest ice-free area of Antarctica. Harsh abiotic conditions of the polar desert ecosystem, including extreme cold, aridity, and limited nutrient availability select for unique taxa. The comparatively simple terrestrial ecosystem is well-suited for investigating edaphic influences on microbial presence, activity, and community structuring. The Dry Valleys are viewed as a useful analog for Mars astrobiology investigations. However, most biotic investigations have been focused on lower elevations, where an understanding of edaphic effects on microbial communities within its generally more favorable conditions has emerged. Transiently wetted Dry Valley water tracks may be analogous to …


Soil Microbial Community Dynamics In Response To Prescribed Extreme Fires Following Juniperus Virginiana Invasion In The Loess Canyons Of Nebraska, Julie A. Fowler Dec 2021

Soil Microbial Community Dynamics In Response To Prescribed Extreme Fires Following Juniperus Virginiana Invasion In The Loess Canyons Of Nebraska, Julie A. Fowler

School of Natural Resources: Dissertations, Theses, and Student Research

In Nebraska and other regions of the Great Plains, the conifer Juniperus virginiana (eastern redcedar) is converting grasslands to dense woodlands. This is driven by the interacting drivers of fire suppression, altered grazing regimes, climate change and other anthropogenic factors, impacting the provisioning of ecosystem services. This vegetation state transition modifies water resource regulation and biogeochemical cycles leading to altered edaphic properties including soil microbial community composition. To restore these grasslands and control J. virginiana spread, prescribed extreme burns are implemented as a management tool through local prescribed burn associations. We hypothesized that the alternative state transition to dense J. …


Aridity-Driven Shift In Biodiversity-Soil Multifunctionality Relationships, Weigang Hu, Jinzhi Ran, Longwei Dong, Qiajun Du, Mingfei Ji, Shuran Yao, Chen Hou, For Full List Of Authors, Download The Pdf. Sep 2021

Aridity-Driven Shift In Biodiversity-Soil Multifunctionality Relationships, Weigang Hu, Jinzhi Ran, Longwei Dong, Qiajun Du, Mingfei Ji, Shuran Yao, Chen Hou, For Full List Of Authors, Download The Pdf.

Biological Sciences Faculty Research & Creative Works

Relationships between biodiversity and multiple ecosystem functions (that is, ecosystem multifunctionality) are context-dependent. Both plant and soil microbial diversity have been reported to regulate ecosystem multifunctionality, but how their relative importance varies along environmental gradients remains poorly understood. Here, we relate plant and microbial diversity to soil multifunctionality across 130 dryland sites along a 4,000 km aridity gradient in northern China. Our results show a strong positive association between plant species richness and soil multifunctionality in less arid regions, whereas microbial diversity, in particular of fungi, is positively associated with multifunctionality in more arid regions. This shift in the relationships …


Construction And Analysis Of Three Multi-Partite Synthetic Microbial Communities, Alexander J. Lazzara, Jacob K. Fanning May 2021

Construction And Analysis Of Three Multi-Partite Synthetic Microbial Communities, Alexander J. Lazzara, Jacob K. Fanning

Honors Theses

Microbial Communities are of interest to molecular biologists hoping to understand the nature of metabolic interactions between co-existing, or possibly mutualistic, organisms. These interactions are ubiquitous in nature, but understanding the molecular mechanisms involved remains challenging and not well understood. Here, we design three tri-partite microbial circuits based on possible interactions among involved microbes, which are discussed and may suggest mutualistic interactions. Carbon and nitrogen molecular pathways and the intracellular metabolism of each microbe is discussed. We present minimal growth media that will ensure that organisms utilize available resources, which may originate from metabolic processes in neighboring microbes, simulating a …


More Than The Sum Of Their Parts: Building A Framework For Understanding Host-Microbe Interactions In Medicago Sativa, Katherine Mackenzie Moccia Dec 2020

More Than The Sum Of Their Parts: Building A Framework For Understanding Host-Microbe Interactions In Medicago Sativa, Katherine Mackenzie Moccia

Doctoral Dissertations

This dissertation seeks to understand plant-microbe interactions in the agriculturally relevant plant Medicago sativa from three distinct vantage points within microbiology. Within the plant microbiome, we examine how primer usage and the application of peptide nucleic acids impacts 16S and 18S rRNA gene sequencing. In doing so, we design a novel peptide nucleic acid, PNA, and test its impact using multiple primers and sequencing protocols. Once microbial sequencing methodology is established, we generate a synthetic consortium of bacterial isolates from M. sativa leaves and modulate nitrogen levels to better understand microbial structure. Drop out communities, where we remove one member …


Applied Species Delimitation In Microbial Taxa And Plants, Austin C. Koontz Dec 2020

Applied Species Delimitation In Microbial Taxa And Plants, Austin C. Koontz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Species are a fundamental concept in biology, and many subdisciplines in biology utilize species in aspects of theory and in the communication of results. Given the centrality of species in biological science, it can seem surprising that there is no universal definition amongst biologists of what, strictly speaking, a species is. In fact, there are, by some estimates, over 20 different "species concepts", and this lack of a consensus is termed "the species problem". This problem has theoretical underpinnings, but has become more relevant as advances in sequencing technologies over the past two decades have allowed researchers to probe the …


Succession In Native Groundwater Microbial Communities In Response To Effluent Wastewater, Chelsea M. Dinon Oct 2020

Succession In Native Groundwater Microbial Communities In Response To Effluent Wastewater, Chelsea M. Dinon

USF Tampa Graduate Theses and Dissertations

Aquifer storage and recovery techniques are used globally to mitigate increasing demands for groundwater. Microcosms were used to evaluate the effect of wastewater effluent that may be used for aquifer storage and recovery injection on native aquifer microbial communities. Sulfur Springs water was used as the source of aquifer water. The microcosms were 100% spring water, 100% unchlorinated filtered wastewater effluent, or one of three mixtures of unchlorinated filtered wastewater effluent and spring water. The mixture microcosms were 50%, 30%, and 10% unchlorinated filtered wastewater effluent with the balance as spring water. The effluent water was UV treated prior to …


Shifts In The Microbiota Associated With Male Mosquitoes (Aedes Aegypti) Exposed To An Obligate Gut Fungal Symbiont (Zancudomyces Culisetae), Jonas Frankel-Bricker Jul 2020

Shifts In The Microbiota Associated With Male Mosquitoes (Aedes Aegypti) Exposed To An Obligate Gut Fungal Symbiont (Zancudomyces Culisetae), Jonas Frankel-Bricker

University Author Recognition Bibliography: 2020

Research characterizing arthropod-associated microbiota has revealed that microbial dynamics can have an important impact on host phenotypic traits. The influence of fungi on these interactions are emerging as targets for research, especially in organisms associated with global human health. A recent study demonstrated colonization of a widespread gut fungus (Zancudomyces culisetae) in a larval mosquito (Aedes aegypti) digestive tract affected microbiomes in larvae and newly emerged adult females (Frankel-Bricker et al. Appl Environ Microbiol, 2020. https://doi.org/10.1128/AEM.02334-19) but did not investigate these processes in males. The objective of the study presented here was to assess fungal influences …