Digital Commons Network^™

Rapid Bacterial And Fungal Successional Dynamics In First Year After Chaparral Wildfire, M. Fabiola Pulido-Chavez, James W. J. Randolph, Cassandra A. Zalman, Loralee Larios, Peter M. Homyak, Sydney I. Glassman

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The rise in wildfire frequency and severity across the globe has increased interest in secondary succession. However, despite the role of soil microbial communities in controlling biogeochemical cycling and their role in the regeneration of post-fire vegetation, the lack of measurements immediately post-fire and at high temporal resolution has limited understanding of microbial secondary succession. To fill this knowledge gap, we sampled soils at 17, 25, 34, 67, 95, 131, 187, 286, and 376 days after a southern California wildfire in fire-adapted chaparral shrublands. We assessed bacterial and fungal biomass with qPCR of 16S and 18S and richness and composition …

Characterizing The Cutaneous Microbiome Of Eurycea Lucifuga As A Potential Defense Against Chytridiomycosis, Madeline Key

Senior Honors Theses

Chytridiomycosis is an emerging infectious disease that is significantly reducing global amphibian populations. The disease is caused by Batrachochytrium dendrobatidis (Bd), a fungus that lethally modifies amphibian skin. Recent research has suggested that the cutaneous microbiome of individual amphibians may play a role in susceptibility to the pathogen. In this study, twelve cave salamanders (Eurycea lucifuga) were collected. Cutaneous bacteria from each salamander were isolated and identified using Sanger Sequencing. Additionally, a Bd-challenge assay was performed to determine each isolate’s antifungal activity. Results indicated many microbial isolates possessed inhibitory capabilities against Bd, which may …

Occurrence Of Kanamycin-Resistant Bacteria Relative To Anthropogenic Pollution Along Richland Creek In Nashville, Tn​, Jolene Ho Mach, Annie Le, Brandon Torres Ramirez

Science University Research Symposium (SURS)

The overuse of antibiotics has caused an increase in antibiotic-resistant (AR) bacteria, which is a serious public health concern. Previous studies showed a significant correlation between anthropogenic pollution and AR bacteria. This project aims to identify AR bacteria in Richland Creek relative to local anthropogenic pollution. Water samples were collected at four locations along Richland Creek in Nashville, Tennessee. Bacteria resistant to the antibiotic kanamycin were isolated from the water samples, identified to genera using DNA barcoding, and compared among the sites. We expect to see a greater abundance and diversity of kanamycin-resistant bacteria closer to the end than near …

Genome Sequence Of Sn1, A Bacteriophage That Infects Sphaerotilus Natans And Pseudomonas Aeruginosa, K.M. Damitha Gunathilake, Denise M. Tremblay, Pier-Luc Plante, Ellen Jensen, Kenneth Nickerson, Sylvain Moineau

Kenneth Nickerson Papers

Phage SN1 infects Sphaerotilus natans and Pseudomonas aeruginosa strains. Its genome consists of 61,858 bp (64.3% GC) and 89 genes, including 32 with predicted functions. SN1 genome is very similar to Pseudomonas phage M6, which contains hypermodified thymidines. Genome analyses revealed similar base-modifying genes as those found in M6.

Phage SN1 was isolated in 1979 from activated sludge samples obtained from a wastewater treatment plant (Lincoln, Nebraska, USA) using S. natans ATCC 13338 as the host (1, 2). An early study showed that the siphophage SN1 has unusual bases in its genome as confirmed by cellulose thin-layer chromatography (1). Its …

Functional Characterization Of Mycobacterium Smegmatis Phage Moomoo Gene Products: Identification Of Toxic Genes, Whitney Heard

Masters Theses & Specialist Projects

Mycobacteriophages are a group of phages that infect members of the genus Mycobacteria. Previous studies have conducted extensive comparisons of the mycobacteriophage genomes and amino acid sequences to establish different phage families. MooMoo is a singleton mycobacteriophage that has been characterized due to its lack of appreciable homology to other phages. Some of its unique properties include its structure and the isolation of a mutant that causes clear plaque phenotypes. The experiments described in this thesis identified three MooMoo phage (gp87, gp90, and gp91) encoded proteins that are toxic to the bacterial host, Mycobacterium smegmatis.Through the use of a …

Microplastics In Freshly Fallen Snow: How May It Adversely Impact Human Health And Exacerbate The Covid-19 Crisis?, Ayesha Liaquat, Aleena Kashif, Sushma Rathi, Alishba Raza

Medical College Documents

No abstract provided.

Discovering Novel Polyextremotolerant Fungi, And Determining Their Ecological Role Within The Biological Soil Crust Consortium, Erin Carr

School of Biological Sciences: Dissertations, Theses, and Student Research

The ecological niche of polyextremotolerant fungi within oligotrophic ecosystems such as biological soil crusts has not yet been determined. These fungi persist in locations where nutrients are depleted while simultaneously surrounded by autotrophic microbes such as algae and cyanobacteria. Yet it has not been shown that they are engaging in any exchange of nutrients the way lichens do. However, there is seemingly no other way for these fungi to obtain vital nutrients, such as carbon or nitrogen, other than from these microbes. Here we have isolated polyextremotolerant fungi from cold desert biological soil crusts which are a microbial biofilm that …

Tissue Decay Tested In Modern Metasequoia Leaves: Implications For Early Diagenesis Of Leaves In Fossil Lagerstätten, Caitlyn R. Witkowski, Qin Leng, Christopher W. Reid, Liang Feng, Hong Yang

Science and Technology Department Faculty Journal Articles

Sedimentary deposits yielding extraordinarily-preserved fossils (known as Lagerstätten) may provide significant insights into the physiology and environments of ancient plants, particularly when the fossils represent their original characteristics with limited diagenetic modifications. To better understand molecular, isotopic, and morphological changes during the early stages of diagenesis, degradation experiments were conducted in two time series: 1) a laboratory decay series using fungi on leaves over the course of a month and 2) a natural decay series with leaves collected from different stages of leaf senescence and early diagenesis. Both experiments used modern leaves of the dawn redwood Metasequoia glyptostroboides …

Analysis Of Soxs In S. Typhimurium By Transposon Mutagenesis, Joel Hanns, Brenda Pratte, Lon Chubiz Phd, Lauren Daugherty

Undergraduate Research Symposium

The mar-sox-rob regulon has been implicated in transcriptional regulation of several stress responses, such efflux of antibiotics, enzymes that break down reactive oxygen species, repression of biofilm formation, or repression of motility through downregulation of flagellar expression. This system is conserved among enteric bacteria and has been studied in species, such as E. coli and S. typhimurium. Some of these mechanisms can be costly and slow cell growth while increasing the probability of survival through tolerance of toxic environments. SoxS works in coordination with SoxR to respond to redox stress encountered by the cell. Interestingly, the overexpression of SoxS …

Describing The Effect Of Thin Layer Sediment Placement On Coastal Microbial Communities Using Foraminifera Diversity, Elizabeth B. Billings

Senior Honors Projects

Salt marshes are rich ecosystems that play an important role in aquatic food systems and prevent erosion while also providing essential habitats for wildlife. Climate change has resulted in rising sea levels and erosion of these coastal wetlands. Thin Layer Sediment Placement (TLP) is a restoration effort being implemented to mitigate the effects of climate change on coastal ecosystems. The TLP process raises elevation of the marsh and provides substrates for vegetative growth by spraying dredged sediment over existing marsh. The impacts of TLP on microbial populations is not widely understood, therefore metrics are required to study the effects of …

Alterations Of The Gut Mycobiome In Patients With Ms - A Bioinformatic Approach, Saumya Shah

Honors Scholar Theses

The mycobiome is the fungal component of the gut microbiome and is implicated in several autoimmune diseases. However, its role in multiple sclerosis (MS) has not been studied. We performed descriptive and formal statistical tests using the R language to characterize the gut mycobiome in people with MS (pwMS) and healthy controls. We found that the microbiome composition of multiple sclerosis patients is different from healthy people. The mycobiome had significantly higher alpha diversity and inter-subject variation in pwMS than controls. Additionally, Saccharomyces and Aspergillus were over-represented in pwMS. Different mycobiome profiles, defined as mycotypes, were associated with different bacterial …

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

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

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

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

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

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

Honors Theses

Antimicrobial resistance is one of the greatest global health challenges of the 21^st 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.

Biology Faculty Scholarship

A polyhydroxybutyrate (PHB)-degrading actinomycete, strain SFB5A^T, 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 SFB5A^T was related to Streptomyces litmocidini JCM 4394^T , 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

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

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

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

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

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

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

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

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

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 …