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Environmental Microbiology and Microbial Ecology

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Temporal And Spatial Comparison Of Pseudo-Nitzschia Species Composition And Domoic Acid In Narragansett Bay, Rhode Island And The Northeast U.S. Shelf, Isabella Church, Bethany D. Jenkins May 2022

Temporal And Spatial Comparison Of Pseudo-Nitzschia Species Composition And Domoic Acid In Narragansett Bay, Rhode Island And The Northeast U.S. Shelf, Isabella Church, Bethany D. Jenkins

Senior Honors Projects

Diatoms are unicellular algae that make up a significant portion of phytoplankton biomass at the base of marine food webs. Narragansett Bay (NB), RI is home to several species of the diatom genus Pseudo-nitzschia (P-n), some of which are known to cause harmful algal blooms through the production of the potent neurotoxin domoic acid (DA). This toxin can lead to Amnesic Shellfish Poisoning in humans through the consumption of affected shellfish. Although the presence of P-n has been well established in NB for over 50 years, DA levels have only recently become a problem, with shellfish harvest closures …


Microbial Contamination On Ambulance Surfaces: A Systematic Literature Review, Adam Obenza, Patricia Cruz, Mark Buttner, D. Woodard Apr 2022

Microbial Contamination On Ambulance Surfaces: A Systematic Literature Review, Adam Obenza, Patricia Cruz, Mark Buttner, D. Woodard

Environmental & Occupational Health Faculty Publications

Healthcare-associated infections (HAIs) are infections that patients acquire while receiving medical treatment in a healthcare facility. During ambulatory transport, the patient may be exposed to pathogens transmitted from emergency medical service (EMS) personnel or EMS surfaces. The aim of this study was to determine whether organisms commonly associated with HAIs have been detected on surfaces in the patient-care compartment of ambulances. Five electronic databases – PubMed, Scopus, Web of Science, Embase and Google Scholar were used to search for articles using inclusion and exclusion criteria following the PRISMA checklist. Inclusion criteria consisted of articles published in English, between 2009 and …


Developing An Electroporation Method For Transforming Streptomyces Nymphaeiformis, Heather Knott, Stephen Baron Apr 2022

Developing An Electroporation Method For Transforming Streptomyces Nymphaeiformis, Heather Knott, Stephen Baron

Honors Projects

Streptomyces species are notoriously difficult to transform. Streptomyces nymphaeiformis is no different, so a method of electroporation was used to attempt to transform the cells. Multiple growth stages were used in order to alter the degree of development of the cell wall. The procedure did not kill the cells, but the cells were not transformed. Due to the lack of transformation with S. nymphaeiformis, transformation was attempted on two other Streptomyces strains, S. lividans and S. coelicolor. Neither was successfully transformed to thiostrepton (tsr) resistance, nor did they grow on a plate lacking thiostrepton. One possibility for the …


Prevalence Of Bacillus Licheniformis On Northern Saw-Whet Owls (Aegolius Acadicus), Lauren Benedict Apr 2022

Prevalence Of Bacillus Licheniformis On Northern Saw-Whet Owls (Aegolius Acadicus), Lauren Benedict

Senior Honors Theses

Birds are hosts to a variety of bacteria and fungi including some that are keratinolytic. These feather degrading bacteria, including Bacillus licheniformis, are capable of degrading β-keratin which is a major component of feathers. While there is little evidence to indicate that feather degrading bacteria are capable of degrading feathers on live birds, there is ample evidence to indicate that many bird species experience altered feather coloration. There is significant variation in the reported prevalence of B. licheniformis on birds with percentages ranging from 6.7% to 99%. This study sought to provide further support for an overall prevalence of …


Life Stage And Proximity To Roads Shape The Skin Microbiota Of Eastern Newts (Notophthalmus Viridescens), Vanessa P. Wuerthner, Jessica Hua, Obed Hernandez-Gomez Mar 2022

Life Stage And Proximity To Roads Shape The Skin Microbiota Of Eastern Newts (Notophthalmus Viridescens), Vanessa P. Wuerthner, Jessica Hua, Obed Hernandez-Gomez

Natural Sciences and Mathematics | Faculty Scholarship

Host-associated microbiomes play an essential role in the health of organisms, including immune system activation, metabolism, and energy uptake. It is well established that microbial communities differ depending on the life stage and natural history of the organism. However, the effects of life stage and natural history on microbial communities may also be influenced by human activities. We investigated the effects of amphibian life stage (terrestrial eft vs. aquatic adult) and proximity to roadways on newt skin bacterial communities. We found that the eft and adult life stages differed in bacterial community composition; however, the effects of roads on community …


Linking Soil Microbial Community Structure To Potential Carbon Mineralization: A Continental Scale Assessment Of Reduced Tillage, Elizabeth L. Rieke, Shannon B. Cappellazzi, Michael Cope, Daniel Liptzin, Gregory Mac Bean, Kelsey L.H. Greub, Charlotte E. Norris, Paul W. Tracy, Ezra Aberle, Amanda Ashworth, Oscar Bañuelos Tavarez, Andy I. Bary, Roland L. Baumhardt, Alberto Borbón Gracia, Daniel C. Brainard, Jameson R. Brennan, Dolores Briones Reyes, Darren Bruhjell, Cameron N. Carlyle, James J.W. Crawford, Cody F. Creech, Steve W. Culman, Bill Deen, Curtis J. Dell, Justin D. Derner, Thomas F. Ducey, Sjoerd W. Duiker, Miles F. Dyck, Benjamin H. Ellert, Avelino Espinosa Solorio, Steven J. Fonte, Simon Fonteyne, Ann-Marie Fortuna, Jamie L. Foster, Lisa M. Fultz, Audrey V. Gamble, Charles M. Geddes, Deirdre Griffin-Lahue, John H. Grove, Stephen K. Hamilton, Xiying Hao, Zachary D. Hayden, Nora Honsdorf, Julie A. Howe, James A. Ippolito, Gregg A. Johnson, Mark A. Kautz, Newell R. Kitchen, Sandeep Kumar, Kirsten S.M. Kurtz, Francis J. Larney, Katie L. Lewis, Matt Liebman, Antonio Lopez Ramirez, Stephen Machado, Bijesh Maharjan, Miguel Angel Martinez Gamiño, William E. May, Mitchel P. Mcclaran, Marshall D. Mcdaniel, Neville Millar, Jeffrey P. Mitchell, Amber D. Moore, Philip A. Moore, Manuel Mora Gutiérrez, Kelly A. Nelson, Emmanuel C. Omondi, Shannon L. Osborne, Leodegario Osorio Alcalá, Philip Owens, Eugenia M. Pena-Yewtukhiw, Hanna J. Poffenbarger, Brenda Ponce Lira, Jennifer R. Reeve, Timothy M. Reinbott, Mark S. Reiter, Edwin L. Ritchey, Kraig L. Roozeboom, Yichao Rui, Amir Sadeghpour, Upendra M. Sainju, Gregg R. Sanford, William F. Schillinger, Robert R. Schindelbeck, Meagan E. Schipanski, Alan J. Schlegel, Kate M. Scow, Lucretia A. Sherrod, Amy L. Shober, Sudeep S. Sidhu, Ernesto Solís Moya, Mervin St Luce, Jeffrey S. Strock, Andrew E. Suyker, Virginia R. Sykes, Haiying Tao, Alberto Trujillo Campos, Laura L. Van Eerd, Nele Verhulst, Tony J. Vyn, Yutao Wang, Dexter B. Watts, Bryan B. William, David L. Wright, Tiequan Zhang, Cristine L.S. Morgan, C. Wayne Honeycutt Mar 2022

Linking Soil Microbial Community Structure To Potential Carbon Mineralization: A Continental Scale Assessment Of Reduced Tillage, Elizabeth L. Rieke, Shannon B. Cappellazzi, Michael Cope, Daniel Liptzin, Gregory Mac Bean, Kelsey L.H. Greub, Charlotte E. Norris, Paul W. Tracy, Ezra Aberle, Amanda Ashworth, Oscar Bañuelos Tavarez, Andy I. Bary, Roland L. Baumhardt, Alberto Borbón Gracia, Daniel C. Brainard, Jameson R. Brennan, Dolores Briones Reyes, Darren Bruhjell, Cameron N. Carlyle, James J.W. Crawford, Cody F. Creech, Steve W. Culman, Bill Deen, Curtis J. Dell, Justin D. Derner, Thomas F. Ducey, Sjoerd W. Duiker, Miles F. Dyck, Benjamin H. Ellert, Avelino Espinosa Solorio, Steven J. Fonte, Simon Fonteyne, Ann-Marie Fortuna, Jamie L. Foster, Lisa M. Fultz, Audrey V. Gamble, Charles M. Geddes, Deirdre Griffin-Lahue, John H. Grove, Stephen K. Hamilton, Xiying Hao, Zachary D. Hayden, Nora Honsdorf, Julie A. Howe, James A. Ippolito, Gregg A. Johnson, Mark A. Kautz, Newell R. Kitchen, Sandeep Kumar, Kirsten S.M. Kurtz, Francis J. Larney, Katie L. Lewis, Matt Liebman, Antonio Lopez Ramirez, Stephen Machado, Bijesh Maharjan, Miguel Angel Martinez Gamiño, William E. May, Mitchel P. Mcclaran, Marshall D. Mcdaniel, Neville Millar, Jeffrey P. Mitchell, Amber D. Moore, Philip A. Moore, Manuel Mora Gutiérrez, Kelly A. Nelson, Emmanuel C. Omondi, Shannon L. Osborne, Leodegario Osorio Alcalá, Philip Owens, Eugenia M. Pena-Yewtukhiw, Hanna J. Poffenbarger, Brenda Ponce Lira, Jennifer R. Reeve, Timothy M. Reinbott, Mark S. Reiter, Edwin L. Ritchey, Kraig L. Roozeboom, Yichao Rui, Amir Sadeghpour, Upendra M. Sainju, Gregg R. Sanford, William F. Schillinger, Robert R. Schindelbeck, Meagan E. Schipanski, Alan J. Schlegel, Kate M. Scow, Lucretia A. Sherrod, Amy L. Shober, Sudeep S. Sidhu, Ernesto Solís Moya, Mervin St Luce, Jeffrey S. Strock, Andrew E. Suyker, Virginia R. Sykes, Haiying Tao, Alberto Trujillo Campos, Laura L. Van Eerd, Nele Verhulst, Tony J. Vyn, Yutao Wang, Dexter B. Watts, Bryan B. William, David L. Wright, Tiequan Zhang, Cristine L.S. Morgan, C. Wayne Honeycutt

Agricultural and Environmental Sciences Faculty Research

Potential carbon mineralization (Cmin) is a commonly used indicator of soil health, with greater Cmin values interpreted as healthier soil. While Cmin values are typically greater in agricultural soils managed with minimal physical disturbance, the mechanisms driving the increases remain poorly understood. This study assessed bacterial and archaeal community structure and potential microbial drivers of Cmin in soils maintained under various degrees of physical disturbance. Potential carbon mineralization, 16S rRNA sequences, and soil characterization data were collected as part of the North American Project to Evaluate Soil Health Measurements (NAPESHM). Results showed that type of cropping system, intensity of physical …


Tiny Earth, Tinier Microbes: An Experiential Learning Approach To Antibiotic Discovery, Emily Kassing Mar 2022

Tiny Earth, Tinier Microbes: An Experiential Learning Approach To Antibiotic Discovery, Emily Kassing

Honors Theses

Antimicrobial resistance is one of the greatest global health challenges of the 21st century as antibiotic discovery has slowed even as scientific knowledge about AMR has progressed. At the same time, science education has turned to active learning approaches like CUREs, or course-based undergraduate research experiences, to achieve educational objectives while engaging students in real-life research. The Tiny Earth Project is a global research initiative that seeks to crowdsource antibiotic discovery by recruiting undergraduate students to screen soil samples for antibiotic producers. The goal of this study was to determine the viability of translating the Tiny Earth programming to …


Characterization Of Streptomyces Nymphaeiformis Sp. Nov., And Its Taxonomic Relatedness To Other Polyhydroxybutyrate-Degrading Streptomycetes, Gary R. Hix, Muhammad S. Khan, Mikayla T. Miller, Elisha C. Napier, Allison L. O'Brien, Roger P. White, Stephen F. Baron Ph.D. Mar 2022

Characterization Of Streptomyces Nymphaeiformis Sp. Nov., And Its Taxonomic Relatedness To Other Polyhydroxybutyrate-Degrading Streptomycetes, Gary R. Hix, Muhammad S. Khan, Mikayla T. Miller, Elisha C. Napier, Allison L. O'Brien, Roger P. White, Stephen F. Baron Ph.D.

Biology Faculty Scholarship

A polyhydroxybutyrate (PHB)-degrading actinomycete, strain SFB5AT, was identified as a species of Streptomyces based on its membrane fatty acid profile and the presence of LL-diaminopimelic acid in the cell wall. It formed sporulating mycelia on most agar media, but flat or wrinkled, moist colonies on trypticase soy agar. Spores were smooth, cylindrical, and borne on long, straight to flexuous chains. It produced a light brown diffusible pigment, but not melanin. Comparison of genomic digital DNA–DNA hybridization (dDDH) and average nucleotide identity (ANI) values indicated that strain SFB5AT was related to Streptomyces litmocidini JCM 4394T , Streptomyces …


The Coxsackievirus And Adenovirus Receptor Has A Short Half-Life In Epithelial Cells, Poornima Kotha Lakshmi Narayan, James M. Readler, Mahmoud S. Alghamri, Trisha L. Brockman, Ray Yan, Priyanka Sharma, Vladislav Snitsarev, Katherine J.D.A Excoffon, Abimbola O. Kolawole Jan 2022

The Coxsackievirus And Adenovirus Receptor Has A Short Half-Life In Epithelial Cells, Poornima Kotha Lakshmi Narayan, James M. Readler, Mahmoud S. Alghamri, Trisha L. Brockman, Ray Yan, Priyanka Sharma, Vladislav Snitsarev, Katherine J.D.A Excoffon, Abimbola O. Kolawole

Department of Biology Faculty Scholarship and Creative Works

The coxsackievirus and adenovirus receptor (CAR) is an essential cellular protein that is involved in cell adhesion, cell signaling, and viral infection. The 8-exon encoded isoform (CAREx8) resides at the apical surface of polarized epithelia, where it is accessible as a receptor for adenovirus entering the airway lumen. Given its pivotal role in viral infection, it is a target for antiviral strategies. To understand the regulation of CAREx8 and determine the feasibility of receptor down regulation, the half-life of total and apical localized CAREx8 was determined and correlated with adenovirus transduction. Total and apical CAREx8 has a relatively short half-life …


Complete Genome Sequences Of Four Putatively Antibiotic-Producing Bacteria Isolated From Soil In Arkansas, Usa, Ruth Plymale, Griffin Hopkins, Taylor Johnson, Taylor Savage, Danielle Schaal Jan 2022

Complete Genome Sequences Of Four Putatively Antibiotic-Producing Bacteria Isolated From Soil In Arkansas, Usa, Ruth Plymale, Griffin Hopkins, Taylor Johnson, Taylor Savage, Danielle Schaal

Articles

Soil bacteria can be a valuable source of antimicrobial compounds. Here, we report the complete genomes of four soil bacteria that were isolated by undergraduate microbiology students as part of a course-based research experience. These genomes were assembled using a hybrid approach combining paired-end Illumina reads with Oxford Nanopore Technologies MinION reads.


Genomic Analysis Of Acetoanaerobium Sp. Vlb-1, An Anaerobic Bacterium Isolated From Nebraska's Eastern Saline Wetlands, Claire Martin Jan 2022

Genomic Analysis Of Acetoanaerobium Sp. Vlb-1, An Anaerobic Bacterium Isolated From Nebraska's Eastern Saline Wetlands, Claire Martin

Honors Theses

Through the analysis of genetic code, the genomic and physiological characteristics of an environmental anaerobic bacterial isolate, Acetoanaerobium sp. strain VLB-1, can be determined and significant pathways can be identified in its significance to the environment. This particular organism was isolated from the Eastern Saline Wetlands in Lincoln, NE. With this isolate, an investigation into elemental and amino acid cycling via the Stickland reaction and the Wood-Ljungdahl pathway was conducted to determine possible metabolic products. The Stickland reaction is a relatively newly discovered pathway, observed in the genus Clostridium. A. sticklandii is the main model for this method of …


The Use Of Probiotic Applications In Early Life Stages To Mitigate Batrachochytrium Dendrobatidis Infections In Rana Luteiventris (Columbia Spotted Frogs), Autumn N. Holley Jan 2022

The Use Of Probiotic Applications In Early Life Stages To Mitigate Batrachochytrium Dendrobatidis Infections In Rana Luteiventris (Columbia Spotted Frogs), Autumn N. Holley

2022 Symposium

Chytridiomycosis, an amphibian skin disease caused by a chytrid fungal pathogen, Batrachochytrium dendrobatidis (Bd), has been linked to global amphibian declines. Some amphibian populations are resistant to severe infection due to symbiotic antifungal skin bacteria, but attempts to develop probiotics from these bacteria have been inconsistently successful because bacteria fail to persist on the skin. Studies have largely been conducted on adult and juvenile amphibians, despite amphibians having fewer known mechanisms for microbiome regulation prior to metamorphosis. We hypothesize that probiotics will persist longer and thus be more effective against pathogen infection if they are applied at an early life …


A Mollicutes Metagenome-Assembled Genome From The Gut Of The Pteropod Limacina Rangii, Zachary T. Pimentel, Patrica S. Thibodeau, Bongkeum Song, Ying Zhang Jan 2022

A Mollicutes Metagenome-Assembled Genome From The Gut Of The Pteropod Limacina Rangii, Zachary T. Pimentel, Patrica S. Thibodeau, Bongkeum Song, Ying Zhang

VIMS Articles

A nearly complete genome of an uncultured Mollicutes sp. was obtained from the metagenome of the gut of Limacina rangii (open-ocean snail), an important grazer and prey for higher trophic animals along the rapidly warming region of the western Antarctic Peninsula.


Drivers Of 20th Century Sea-Level Change In Southern New Zealand Determined From Proxy And Instrumental Records, Ed Garrett, W. Roland Gehrels, Bruce W. Hayward, Rewi Newnham, Maria J. Gehrels, Craig J. Morey, Sönke Dangendorf Jan 2022

Drivers Of 20th Century Sea-Level Change In Southern New Zealand Determined From Proxy And Instrumental Records, Ed Garrett, W. Roland Gehrels, Bruce W. Hayward, Rewi Newnham, Maria J. Gehrels, Craig J. Morey, Sönke Dangendorf

CCPO Publications

In this paper we present new proxy-based sea-level reconstructions for southern New Zealand spanning the last millennium. These palaeo sea-level records usefully complement sparse Southern Hemisphere proxy and tide-gauge sea-level datasets and, in combination with instrumental observations, can test hypotheses about the drivers of 20th century global sea-level change, including land-based ice melt and regional sterodynamics. We develop sea-level transfer functions from regional datasets of salt-marsh foraminifera to establish a new proxy-based sea-level record at Mokomoko Inlet, at the southern tip of the South Island, and to improve the previously published sea-level reconstruction at Pounawea, located about 110 km to …


Defining The Realized Niche Of The Two Major Clades Of Trichodesmium: A Study On The West Florida Shelf, Kristina A. Confesor, Corday R. Selden, Kimberly E. Powell, Laura A. Donahue, Travis Mellett, Salvatore Caprara, Angela N. Knapp, Kristen N. Buck, P. Dreux Chappell Jan 2022

Defining The Realized Niche Of The Two Major Clades Of Trichodesmium: A Study On The West Florida Shelf, Kristina A. Confesor, Corday R. Selden, Kimberly E. Powell, Laura A. Donahue, Travis Mellett, Salvatore Caprara, Angela N. Knapp, Kristen N. Buck, P. Dreux Chappell

OES Faculty Publications

The cyanobacterium Trichodesmium plays an essential role supporting ocean productivity by relieving nitrogen limitation via dinitrogen (N-2) fixation. The two common Trichodesmium clades, T. erythraeum and T. thiebautii, are both observed in waters along the West Florida Shelf (WFS). We hypothesized that these taxa occupy distinct realized niches, where T. thiebautii is the more oceanic clade. Samples for DNA and water chemistry analyses were collected on three separate WFS expeditions (2015, 2018, and 2019) spanning multiple seasons; abundances of the single copy housekeeping gene rnpB from both clades were enumerated via quantitative PCR. We conducted a suite of statistical …


Evidence For Metabolic Diversity In Meso-Neoproterozoic Stromatolites (Vazante Group, Brazil), Flavia Callefo, Fresia Ricardi-Branco, Mirian Mírian Liza Alves Forancelli Pacheco, Alexandre Ribeiro Cardoso, Nora Noffke, Verônica De Carvalho Teixeira, Itamar Tomio Neckel, Lara Maldanis, Emma Bullock, Dina Bower, Adalene Moreira Silva, Dario Ferreira Sanchez, Fabio Rodrigues, Douglas Galante Jan 2022

Evidence For Metabolic Diversity In Meso-Neoproterozoic Stromatolites (Vazante Group, Brazil), Flavia Callefo, Fresia Ricardi-Branco, Mirian Mírian Liza Alves Forancelli Pacheco, Alexandre Ribeiro Cardoso, Nora Noffke, Verônica De Carvalho Teixeira, Itamar Tomio Neckel, Lara Maldanis, Emma Bullock, Dina Bower, Adalene Moreira Silva, Dario Ferreira Sanchez, Fabio Rodrigues, Douglas Galante

OES Faculty Publications

Deciphering the evolution of ecological interactions among the metabolic types during the early diversification of life on Earth is crucial for our understanding of the ancient biosphere. The stromatolites from the genus Conophyton cylindricus represent a datum for the Proterozoic (Meso to Neoproterozoic) on Earth. Their typical conical shape has been considered a result of a competition between microorganisms for space, light and nutrients. Well-preserved records of this genus from the "Paleontological Site of Cabeludo ", Vazante Group, São Francisco Craton (Southern Brazil) present in situ fossilized biofilms, containing preserved carbonaceous matter. Petrographic and geochemical analyses revealed an alternation between …


Microbial Labilization And Diversification Of Pyrogenic Dissolved Organic Matter, Aleksandar I. Goranov, Andrew S. Wozniak, Kyle W. Bostick, Andrew R. Zimmerman, Siddhartha Mitra, Patrick G. Hatcher Jan 2022

Microbial Labilization And Diversification Of Pyrogenic Dissolved Organic Matter, Aleksandar I. Goranov, Andrew S. Wozniak, Kyle W. Bostick, Andrew R. Zimmerman, Siddhartha Mitra, Patrick G. Hatcher

Chemistry & Biochemistry Faculty Publications

With the increased occurrence of wildfires around the world, interest in the chemistry of pyrogenic organic matter (pyOM) and its fate in the environment has increased. Upon leaching from soils by rain events, significant amounts of dissolved pyOM (pyDOM) enter the aquatic environment and interact with microbial communities that are essential for cycling organic matter within the different biogeochemical cycles. To evaluate the biodegradability of pyDOM, aqueous extracts of laboratory-produced biochars were incubated with soil microbes, and the molecular changes to the composition of pyDOM were probed using ultrahigh-resolution mass spectrometry (Fourier transform–ion cyclotron resonance–mass spectrometry). Given that solar irradiation …


A Mathematical Model For Transport And Growth Of Microbes In Unsaturated Porous Soil, Harihar Khanal, Andrei Ludu, Ramesh Chandra Timsina, Kedar Nath Uprety Dec 2021

A Mathematical Model For Transport And Growth Of Microbes In Unsaturated Porous Soil, Harihar Khanal, Andrei Ludu, Ramesh Chandra Timsina, Kedar Nath Uprety

Publications

In this work, we develop a mathematical model for transport and growth of microbes by natural (rain) water infiltration and flow through unsaturated porous soil along the vertical direction under gravity and capillarity by coupling a system of advection diffusion equations (for concentration of microbes and their growth-limiting substrate) with the Richards equation. (e model takes into consideration several major physical, chemical, and biological mechanisms. (e resulting coupled system of PDEs together with their boundary conditions is highly nonlinear and complicated to solve analytically. We present both a partial analytic approach towards solving the nonlinear system and finding the main …


Farnesol Secretion As A Possible Driving Force For Maintaining Candida Albicans As A Diploid, Kenneth Nickerson, Cory Boone, Kory Parker Dec 2021

Farnesol Secretion As A Possible Driving Force For Maintaining Candida Albicans As A Diploid, Kenneth Nickerson, Cory Boone, Kory Parker

Kenneth Nickerson Papers

Candida albicans is a pathogenic dimorphic fungus which is invariably found as a diploid in patients. C. albicans secretes the sesquiterpene farnesol both as a quorum sensing molecule which blocks the yeast to hypha conversion and as a virulence factor for pathogenicity. 20-25 μM farnesol kills other competing yeasts and fungi, often by triggering apoptosis, and yet wild type diploid C. albicans tolerates 300-500 μM farnesol. The recent availability of 10 haploid strains of C. albicans (5 mating type aand 5 mating type α) allowed us to compare their production of and sensitivity to farnesol. On average, the heterozygous diploid …


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. …


Rhizobium Symbiotic Capacity Shapes Root-Associated Microbiomes In Soybean, Yuanhui Lu, Bin Ma, Wenfeng Chen, Klaus Schlaeppi, Matthias Erb, Erinne Stirling, Lingfei Hu, Entao Wang, Yunzeng Zhang, Kankan Zhao, Zhijiang Lu, Shudi Ye, Jianming Xu Dec 2021

Rhizobium Symbiotic Capacity Shapes Root-Associated Microbiomes In Soybean, Yuanhui Lu, Bin Ma, Wenfeng Chen, Klaus Schlaeppi, Matthias Erb, Erinne Stirling, Lingfei Hu, Entao Wang, Yunzeng Zhang, Kankan Zhao, Zhijiang Lu, Shudi Ye, Jianming Xu

Environmental Science and Geology Faculty Research Publications

Root-microbiome interactions are of central importance for plant performance and yield. A distinctive feature of legumes is that they engage in symbiosis with N2-fixing rhizobia. If and how the rhizobial symbiotic capacity modulates root-associated microbiomes are still not yet well understood. We determined root-associated microbiomes of soybean inoculated with wild type (WT) or a noeI mutant of Bradyrhizobium diazoefficiens USDA 110 by amplicon sequencing. UPLC-MS/MS was used to analyze root exudates. The noeI gene is responsible for fucose-methylation of Nod factor secreted by USDA 110 WT strain. Soybean roots inoculated with the noeI mutant showed a significant decrease …


Dietary Fiber Utilization In The Gut: The Role Of Human Gut Microbes In The Degradation And Consumption Of Xylose-Based Carbohydrates, Elizabeth Drey Nov 2021

Dietary Fiber Utilization In The Gut: The Role Of Human Gut Microbes In The Degradation And Consumption Of Xylose-Based Carbohydrates, Elizabeth Drey

Department of Food Science and Technology: Dissertations, Theses, and Student Research

Xylans are a family of xylose-based polysaccharides naturally present in fruits, vegetables, and cereal grains. Resistant to digestion by host enzymes, xylans reach the large intestine intact, where they are utilized by members of the gut microbiome. They are initially hydrolyzed by primary degraders that utilize extracellular xylanases to cleave xylan into smaller oligomers. These xylooligosaccharides (XOS) can then either be further hydrolyzed by primary degraders or can cross-feed secondary consumers, including Bifidobacterium. While several Bifidobacterium species have metabolic systems for XOS, studies have shown these species grow poorly on longer XOS and xylan substrates. In this thesis, …


Spotted Salamander Egg Masses Exhibit A Unique Internal Microbiome In Relation To Their Environment, Elizabeth Leonard Nov 2021

Spotted Salamander Egg Masses Exhibit A Unique Internal Microbiome In Relation To Their Environment, Elizabeth Leonard

Senior Honors Theses

Microbial studies have led to various ecological and medicinal discoveries. Amphibian eggs, like those of Ambystoma maculatum, exhibit natural resistance to bacterial invasion that may be microbiome related. The purpose of this research was to sequence the external and internal microbiome of A. maculatum egg masses and compare with the environmental microbiome. It was hypothesized that the external and internal microbiome would bear more similarity to each other than the water. A significant difference was observed between the microbiome of the inside surface of the egg mass and the water but not the outside surface of the egg and …


Human Fecal Contamination Corresponds To Changes In The Freshwater Bacterial Communities Of A Large River Basin, Jill Mcclary-Gutierrez, Zac Driscoll, Cheryl Nenn Sep 2021

Human Fecal Contamination Corresponds To Changes In The Freshwater Bacterial Communities Of A Large River Basin, Jill Mcclary-Gutierrez, Zac Driscoll, Cheryl Nenn

Freshwater Faculty Articles

Microbial water quality is generally monitored by culturable fecal indicator bacteria (FIB), which are intended to signal human health risk due to fecal pollution. However, FIB have limited utility in most urbanized watersheds as they do not discriminate among fecal pollution sources, tend to make up a small fraction of the total microbial community, and do not inform on pollution impacts on the native ecosystem. To move beyond these limitations, we assessed entire bacterial communities and investigated how bacterial diversity relates to traditional ecological and human health-relevant water quality indicators throughout the Milwaukee River Basin. Samples were collected from 16 …


Sterol Biosynthesis In Four Green Algae: A Bioinformatic Analysis Of The Ergosterol Versus Phytosterol Decision Point, Adam Voshall, Nakeirah T.M. Christie, Suzanne L. Rose, Maya Khasin, James L. Van Etten, Jennifer E. Markham, Wayne Riekhof, Kenneth Nickerson Aug 2021

Sterol Biosynthesis In Four Green Algae: A Bioinformatic Analysis Of The Ergosterol Versus Phytosterol Decision Point, Adam Voshall, Nakeirah T.M. Christie, Suzanne L. Rose, Maya Khasin, James L. Van Etten, Jennifer E. Markham, Wayne Riekhof, Kenneth Nickerson

Kenneth Nickerson Papers

Animals and fungi produce cholesterol and ergosterol, respectively, while plants produce the phytosterols stigmasterol, campesterol, and β-sitosterol in various combinations. The recent sequencing of many algal genomes allows the detailed reconstruction of the sterol metabolic pathways. Here, we characterized sterol synthesis in two sequenced Chlorella spp., the free-living C. sorokiniana, and symbiotic C. variabilis NC64A. Chlamydomonas reinhardtii was included as an internal control and Coccomyxa subellipsoidea as a plant-like outlier. We found that ergosterol was the major sterol produced by Chlorella spp. and C. reinhardtii, while C. subellipsoidea produced the three phytosterols found in plants. In silico analysis of the …


Structure Of Chimpanzee Gut Microbiomes Across Tropical Africa, Clifton P. Bueno De Mesquita, Lauren M. Nichols, Matthew J. Gebert, Caihong Vanderburgh, Gaëlle Bocksberger, Jack D. Lester, Ammie K. Kalan, Paula Dieguez, Maureen S. Mccarthy, Anthony Agbor, Paula Álvarez Varona, Ayuk Emmanuel Ayimisin, Mattia Bessone, Rebecca Chancellor, Heather Cohen, Charlotte Coupland, Tobias Deschner, Villard Ebot Egbe, Annemarie Goedmakers, Anne-Céline Granjon, Cyril C. Grueter, Josephine Head, R. Adriana Hernandez-Aguilar, Kathryn J. Jeffery, Sorrel Jones, Parag Kadam, Michael Kaiser, Juan Lapuente, Bradley Larson, Sergio Marrocoli, David Morgan, Badru Mugerwa, Felix Mulindahabi, Emily Neil, Protais Niyigaba, Liliana Pacheco, Alex K. Piel, Martha M. Robbins, Aaron S. Rundus, Crickette M. Sanz, Lilah Sciaky, Douglas Sheil, Volker Sommer, Fiona A. Stewart, Els Ton, Joost Van Schijndel, Virginie Vergnes, Erin G. Wessling, Roman M. Wittig, Yisa Ginath Yuh, Kyle Yurkiw, Klaus Zuberbühler, Jan F. Gogarten, Anna Heintz-Buschart, Alexandra N. Muellner-Riehl, Christophe Boesch, Hjalmar S. Kühl, Noah Fierer, Mimi Arandjelovic, Robert R. Dunn Jun 2021

Structure Of Chimpanzee Gut Microbiomes Across Tropical Africa, Clifton P. Bueno De Mesquita, Lauren M. Nichols, Matthew J. Gebert, Caihong Vanderburgh, Gaëlle Bocksberger, Jack D. Lester, Ammie K. Kalan, Paula Dieguez, Maureen S. Mccarthy, Anthony Agbor, Paula Álvarez Varona, Ayuk Emmanuel Ayimisin, Mattia Bessone, Rebecca Chancellor, Heather Cohen, Charlotte Coupland, Tobias Deschner, Villard Ebot Egbe, Annemarie Goedmakers, Anne-Céline Granjon, Cyril C. Grueter, Josephine Head, R. Adriana Hernandez-Aguilar, Kathryn J. Jeffery, Sorrel Jones, Parag Kadam, Michael Kaiser, Juan Lapuente, Bradley Larson, Sergio Marrocoli, David Morgan, Badru Mugerwa, Felix Mulindahabi, Emily Neil, Protais Niyigaba, Liliana Pacheco, Alex K. Piel, Martha M. Robbins, Aaron S. Rundus, Crickette M. Sanz, Lilah Sciaky, Douglas Sheil, Volker Sommer, Fiona A. Stewart, Els Ton, Joost Van Schijndel, Virginie Vergnes, Erin G. Wessling, Roman M. Wittig, Yisa Ginath Yuh, Kyle Yurkiw, Klaus Zuberbühler, Jan F. Gogarten, Anna Heintz-Buschart, Alexandra N. Muellner-Riehl, Christophe Boesch, Hjalmar S. Kühl, Noah Fierer, Mimi Arandjelovic, Robert R. Dunn

Psychology Faculty Publications

Understanding variation in host-associated microbial communities is important given the relevance of microbiomes to host physiology and health. Using 560 fecal samples collected from wild chimpanzees (Pan troglodytes) across their range, we assessed how geography, genetics, climate, vegetation, and diet relate to gut microbial community structure (prokaryotes, eukaryotic parasites) at multiple spatial scales. We observed a high degree of regional specificity in the microbiome composition, which was associated with host genetics, available plant foods, and potentially with cultural differences in tool use, which affect diet. Genetic differences drove community composition at large scales, while vegetation and potentially tool use drove …


Dom Degradation By Light And Microbes Along The Yukon River‑Coastal Ocean Continuum, Brice K. Grunert, Maria Tzortziou, Patrick Neale, Alana Menendez, Peter Hernes May 2021

Dom Degradation By Light And Microbes Along The Yukon River‑Coastal Ocean Continuum, Brice K. Grunert, Maria Tzortziou, Patrick Neale, Alana Menendez, Peter Hernes

Publications and Research

The Arctic is experiencing rapid warming, resulting in fundamental shifts in hydrologic connectivity and carbon cycling. Dissolved organic matter (DOM) is a significant component of the Arctic and global carbon cycle, and significant perturbations to DOM cycling are expected with Arctic warming. The impact of photochemical and microbial degradation, and their interactive effects, on DOM composition and remineralization have been documented in Arctic soils and rivers. However, the role of microbes, sunlight and their interactions on Arctic DOM alteration and remineralization in the coastal ocean has not been considered, particularly during the spring freshet when DOM loads are high, photoexposure …


Resistance Of The Freshwater Microbiome To A Combination Of Pesticides, Gabriel Hooper May 2021

Resistance Of The Freshwater Microbiome To A Combination Of Pesticides, Gabriel Hooper

Senior Honors Theses

Pesticides are used prevalently throughout the United States and can negatively affect non-target organisms. Rain run-off can move multiple pesticides into freshwater ecosystems and bring them in contact with non-target organisms that have variable tolerances to pollution. This study seeks to improve our understanding of how an acute exposure to a combination of pesticides may restructure microbial communities by examining the microbiome before and after a 48-hour exposure to 2000 ppb of herbicides (glyphosate, atrazine, and 2,4-D). Pesticide exposure did not significantly alter the alpha or beta diversity of the sample types, which demonstrates the ability of freshwater microbiomes to …


A Novel Jumbo Phage Phima05 Inhibits Harmful Microcystis Sp., Ampapan Naknaen, Oramas Suttinun, Komwit Surachat, Eakalak Khan, Rattanaruji Pomwised Apr 2021

A Novel Jumbo Phage Phima05 Inhibits Harmful Microcystis Sp., Ampapan Naknaen, Oramas Suttinun, Komwit Surachat, Eakalak Khan, Rattanaruji Pomwised

Civil and Environmental Engineering and Construction Faculty Research

Microcystis poses a concern because of its potential contribution to eutrophication and production of microcystins (MCs). Phage treatment has been proposed as a novel biocontrol method for Microcystis. Here, we isolated a lytic cyanophage named PhiMa05 with high efficiency against MCs-producing Microcystis strains. Its burst size was large, with approximately 127 phage particles/infected cell, a short latent period (1 day), and high stability to broad salinity, pH and temperature ranges. The PhiMa05 structure was composed of an icosahedral capsid (100 nm) and tail (120 nm), suggesting that the PhiMa05 belongs to the Myoviridae family. PhiMa05 inhibited both planktonic and aggregated …


Growth Of Diatom Fistulifera Alcalina In Bacterial Co-Culture And Comparative Mitogenomics Of Fistulifera Species, Erwin David Berthold Mar 2021

Growth Of Diatom Fistulifera Alcalina In Bacterial Co-Culture And Comparative Mitogenomics Of Fistulifera Species, Erwin David Berthold

FIU Electronic Theses and Dissertations

Diatoms are excellent biological models of growth and intracellular oil generation. The productivity and compounds of diatoms, especially oils, support aquatic food chains and human medical and industrial needs. The qualities that made diatoms prolific producers, specifically diatom physiological features such as growth rates with intracellular lipid storage in alkaline environments, are however poorly understood. Another physiological aspect that remains unexplored is the effects of bacteria on the growth and lipid production of alkaliphilic diatoms. More studies, especially co-cultures, are needed for advances in diatom biology and strain performance for the algal biotechnological field. Besides physiology, diatom genetics using next-generation …