Life Sciences Commons^™

Microbial Community Shifts Caused By Changes In The Primary Oxidant At A Drinking Water Treatment Plant, Connie Marie Moloney

Graduate Theses and Dissertations

Microbial communities resistant to common oxidants can cause concerns for water treatment plants (WTPs). If a bacterium is not fully oxidized during disinfection, these species can impede upon filtration processes or seed biofilms in the distribution system. In an effort to minimize disinfection by-products (DBP's) that result from the reaction of chlorine (Cl2) with natural organic matter, water treatment plants have the option to change their primary oxidant to chlorine dioxide (ClO2). The following study examines the change in microbial communities during the sedimentation process under differing oxidation regimes, specifically chlorine (Cl2) and ClO2 at the local water treatment plant …

The Effects Of Hmtba (2-Hydroxy-4-Methylthio-Butanoic Acid) Supplementation On Ruminal Microbial Crude Protein Synthesis And Community Structure In Dairy Cattle, Chad J. R. Jenkins

Department of Animal Science: Dissertations, Theses, and Student Research

Metabolizable protein (MP) is protein that reaches the small intestine and is available for absorption and utilization by the cow. Dairy rations may be limited in the supply of MP essential to meeting the demands of milk synthesis, however as much as half of the MP flowing to the small intestine may be attributed to microbial origins and is referred to as microbial CP (MCP). Experiment 1 utilized a technique in which DNA was used as a microbial marker to estimate the concentration of bacterial CP (BCP) in the solid and liquid portions of rumen digesta. Rumen digesta was sampled …

Predation Thresholds In Marine Microbial Communities Applied To Environments With Low Prey Abundances, Bonnie Bailey

OES Theses and Dissertations

Prokaryotes (Bacteria and Archaea) comprise the largest component of biomass in the world's oceans. Their abundances are controlled by resource availability, viral infections and protist grazing. Many pico- and nano-eukaryotic predators grow almost as quickly as their prey, and greatly increase in numbers as soon as their prey do, leading in tum to depletion in prokaryotes. It is still unclear however, as to what extent microbial predators are able to feed in low prey environments, most prominently in the largest biome on Earth, the deep sea (below l 000 m depth). It has been hypothesized that in low prey environments, …

Differences In Innate Immune Signaling Between Alcoholic And Non-Alcoholic Steatohepatitis, Jan Petrasek, Timea Csak, Michal Ganz, Gyongyi Szabo

Gyongyi Szabo

The similar histopathological characteristics of alcoholic steatohepatitis (ASH) and non-alcoholic steatohepatitis (NASH), and the crucial role of the innate immune response in both conditions may lead to the assumption that ASH and NASH represent the same pathophysiological entities caused by different risk factors. In this review paper, we elaborate on the pathophysiological differences between these two entities and highlight the disease-specific involvement of signaling molecules downstream of the Toll-like receptor 4, and the differential mechanism by which the inflammasome contributes to ASH versus NASH. Our findings emphasize that ASH and NASH have disease-specific mechanisms and therefore represent distinct biological entities. …

Nisin Resistance Of Bacillus Cerus: Preparation Of Nisin, Peter Weber

Journal of Undergraduate Research at Minnesota State University, Mankato

Nisin is a peptide that is made by the bacterium Lactococcus lactis. Nisin is a small molecule that kills gram positive bacteria by binding to their membrane and by disrupting the proton motive force. When food is processed it is heated to kill bacteria, but some bacteria still survive. Adding nisin to the food provides a second barrier for the growth of the bacteria. Purified nisin has become quite expensive in the current marketplace. Therefore this study is directed at producing nisin and purifying it. L. lactis was grown in five different media (BHI, BHI + 1% glucose, BHI + …

Acute Effects Of Tio2 Nanomaterials On The Viability And Taxonomic Composition Of Aquatic Bacterial Communities Assessed Via High-Throughput Screening And Next Generation Sequencing, Binh Chu, Tiezheng Tong, Jean-François Gaillard, Kimberley A. Gray, John J. Kelly

Biology: Faculty Publications and Other Works

The nanotechnology industry is growing rapidly, leading to concerns about the potential ecological consequences of the release of engineered nanomaterials (ENMs) to the environment. One challenge of assessing the ecological risks of ENMs is the incredible diversity of ENMs currently available and the rapid pace at which new ENMs are being developed. High-throughput screening (HTS) is a popular approach to assessing ENM cytotoxicity that offers the opportunity to rapidly test in parallel a wide range of ENMs at multiple concentrations. However, current HTS approaches generally test one cell type at a time, which limits their ability to predict responses of …

Airborne Microorganisms In Lascaux Cave (France), Pedro M Martin-Sanchez, Valme Jurado, Estefania Porca, Fabiola Bastian, Delphine Lacanette, Claude Alabouvette, Cesareo Saiz-Jimenez

International Journal of Speleology

Lascaux Cave in France contains valuable Palaeolithic paintings. The importance of the paintings, one of the finest examples of European rock art paintings, was recognized shortly after their discovery in 1940. In the 60’s of the past century the cave received a huge number of visitors and suffered a microbial crisis due to the impact of massive tourism and the previous adaptation works carried out to facilitate visits. In 1963, the cave was closed due to the damage produced by visitors’ breath, lighting and algal growth on the paintings. In 2001, an outbreak of the fungus Fusarium solani covered the …

Characterization Of A Putative Cephalotoxin From The Hemocytes Of Euprymna Scolopes, Jessie E. Scott

University Scholar Projects

Many organisms have beneficial microbial symbionts, and complex interactions between the immune system and the bacteria must occur to allow these symbioses to persist. The host immune system must recognize and preferentially tolerate the beneficial microorganisms, while simultaneously eliminating harmful pathogens. The Hawaiian bobtail squid, Euprymna scolopes, is a model organism for host-microbe interactions because of the unique light organ symbiosis. Hemocytes, the squid’s primary immune cell, infiltrate and patrol the light organ and continuously interact with the symbiont Vibrio fischeri. Using this model, several innate immunity genes have been shown to be differentially expressed in the hemocytes …

A Mathematical Model Of Moisture Movement And Bacterial Growth In Two-Dimensional Porous Medium, Rachel Elizabeth Tewinkel

Theses and Dissertations

Bacterial growth in sand is of concern in regard to the health of beaches. A mathematical model is presented that represents the movement of moisture and the growth of bacteria through a beach. Simulations were run by numerically solving Richards Equation using a Finite Volume Method in order to track moisture movement. A model of moisture-dependent bacterial growth was then implemented. These simulations show that elevated bacteria counts following rain events do not necessarily result from bacteria in the body of water, but can also be sourced from the sand. Additionally, four different moisture-dependent bacterial growth models are compared to …

Prokaryotic Diversity Of The Wastewater Outfalls, Reefs, And Inlets Of Broward County, Alexandra Mandina Campbell

HCNSO Student Theses and Dissertations

We applied culture-independent, next-generation sequencing (NGS) high throughput pyrosequencing, to characterize the microbial communities associated with near shore seawater in Broward County, FL. These waters flow over coral reef communities, which are part of the Florida reef tract, and are close to shore where bathers frequent. Through a close partnership with the NOAA FACE program, 38 total seawater samples were taken from 6 distinct locales -the Port Everglades and Hillsboro Inlets, Hollywood and Broward wastewater outfalls, and the associated reef waters-over the course of one year. Tagged 16S rRNA amplicons were used to generate longitudinal taxonomic profiles of marine bacteria …

Antimicrobial Resistance Of Channel Catfish Intestinal Microflora In The Arkansas And Ninnescah Rivers In Kansas, Jordan R. Hofmeier

Master's Theses

Antimicrobial compounds have been used by humans to counteract bacterial infections since 1910. Overuse of these compounds in clinical and agricultural applications has led to rapid evolution and global spread of antimicrobial resistance and rivers are the main receiving body for antimicrobials and resistant bacteria from urban effluents and agricultural runoff. When antimicrobial-resistant bacteria enter the aquatic environment, water acts as a physical pathway for their distribution. Subsequently, resistance genes become established in natural systems and pose threats to human health and ecological processes. Due to these potential threats, antimicrobial resistance in the aquatic environment should be closely monitored. To …

Dispersal Of Antibiotic-Resistant Bacteria Near Central Great Plains Feedlots, Jennifer R. Pfannenstiel-Klaus

Master's Theses

Antibiotic resistance is a growing concern in medical and veterinary settings. Resistance can be worsened by misuse and overuse of antibiotics. Such situations can give rise to highly resistant organisms. Ciprofloxacin, a synthetic, broad-spectrum antibiotic used to treat gram-positive and gram-negative infections in humans, has similar chemical structure to enrofloxacin, which is used to treat animals. Cross-resistance might arise because of that similarity. This research describes the dispersal and prevalence of bacteria that exhibit ciprofloxacin resistance in relation to feedlots in the central Great Plains region. Six times in 2013, six feedlots were sampled for airborne bacterial communities at, upwind …

Antimicrobial And Antiinsectan Phenolic Metabolites Of Dalea Searlsiae, Gil Belofsky, Mario Aronica, Eric Foss, Jane Diamond, Felipe Santana, Jacob Darley, Patrick F. Dowd, Christina M. Coleman, Daneel Ferreira

All Faculty Scholarship for the College of the Sciences

Continued interest in the chemistry of Dalea spp. led to investigation of Dalea searlsiae, a plant native to areas of the western United States. Methanol extractions of D. searlsiae roots and subsequent chromatographic fractionation afforded the new prenylated and geranylated flavanones malheurans A–D (1–4) and known flavanones (5 and 6). Known rotenoids (7 and 8) and isoflavones (9 and 10) were isolated from aerial portions. Structure determination of pure compounds was accomplished primarily by extensive 1D- and 2D-NMR spectroscopy. The absolute configurations of compounds 1–5, 7 …

The Gut Of Geographically Disparate Ciona Intestinalis Harbors A Core Microbiota, Larry J. Dishaw, Jaime Flores-Torres, Simon Lax, Kristina Gemayel, Brittany Leigh, Daniela Melillo, M. Gail Mueller, Lenina Natale, Ivana Zucchetti, Rosaria De Santis, Maria Rosaria Pinto, Gary W. Litman, Jack W. Gilbert

Marine Science Faculty Publications

It is now widely understood that all animals engage in complex interactions with bacteria (or microbes) throughout their various life stages. This ancient exchange can involve cooperation and has resulted in a wide range of evolved host-microbial interdependencies, including those observed in the gut. Ciona intestinalis, a filter-feeding basal chordate and classic developmental model that can be experimentally manipulated, is being employed to help define these relationships. Ciona larvae are first exposed internally to microbes upon the initiation of feeding in metamorphosed individuals; however, whether or not these microbes subsequently colonize the gut and whether or not Ciona forms …

Effects Of Urban Stream Burial On Organic Matter Dynamics And Reach Scale Nitrate Retention, Jake J. Beaulieu, Paul M. Mayer, Sujay S. Kaushal, Michael J. Pennino, Clay P. Arango, David A. Balz, Timothy J. Canfield, Colleen M. Elonen, Ken M. Fritz, Brian H. Hill, Hodon Ryu, Jorge W. Santo Domingo

All Faculty Scholarship for the College of the Sciences

Nitrogen (N) retention in streams is an important ecosystem service that may be affected by the widespread burial of streams in stormwater pipes in urban watersheds. We predicted that stream burial suppresses the capacity of streams to retain nitrate (NO₃ ⁻) by eliminating primary production, reducing respiration rates and organic matter availability, and increasing specific discharge. We tested these predictions by measuring whole-stream NO₃ ⁻ removal rates using ¹⁵NO₃ ⁻ isotope tracer releases in paired buried and open reaches in three streams in Cincinnati, Ohio (USA) during four seasons. Nitrate uptake lengths were 29 times …

Induced Transcriptional Profiling Of Phenylpropanoid Pathway Genes Increased Flavonoid And Lignin Content In Arabidopsis Leaves In Response To Microbial Products, Mohammad Babar Ali, David H. Mcnear

Plant and Soil Sciences Faculty Publications

BACKGROUND: The production and use of biologically derived soil additives is one of the fastest growing sectors of the fertilizer industry. These products have been shown to improve crop yields while at the same time reducing fertilizer inputs to and nutrient loss from cropland. The mechanisms driving the changes in primary productivity and soil processes are poorly understood and little is known about changes in secondary productivity associated with the use of microbial products. Here we investigate secondary metabolic responses to a biologically derived soil additive by monitoring changes in the phenlypropanoid (PP) pathway in Arabidopsis thaliana.

RESULTS: This study …

Priming In The Microbial Landscape: Periphytic Algal Stimulation Of Litter-Associated Microbial Decomposers, Kevin A. Kuehn, Steven N. Francoeur, Robert H. Findlay, Robert K. Neely

Faculty Publications

Microbial communities associated with submerged detritus in aquatic ecosystems often comprise a diverse mixture of autotrophic and heterotrophic microbes, including algae, bacteria, protozoa, and fungi. Recent studies have documented increased rates of plant litter mass loss when periphytic algae are present. We conducted laboratory and field experiments to assess potential metabolic interactions between natural autotrophic and heterotrophic microbial communities inhabiting submerged decaying plant litter of Typha angustifolia and Schoenoplectus acutus. In the field, submerged plant litter was either exposed to natural sunlight or placed under experimental canopies that manipulated light availability and growth of periphytic algae. Litter was collected …

The Effects Of Insects, Nutrients, And Plant Invasion On Community Structure And Function Above- And Belowground, Phoebe Wright, Melissa A. Cregger, Lara Souza, Nathan J. Sanders, Aimee T. Classen

Faculty Publications and Other Works -- Ecology and Evolutionary Biology

Soil nutrient availability, invasive plants, and insect presence can directly alter ecosystem structure and function, but less is known about how these factors may interact. In this 6-year study in an old-field ecosystem, we manipulated insect abundance (reduced and control), the propagule pressure of an invasive nitrogen-fixing plant (propagules added and control), and soil nutrient availability (nitrogen added, nitrogen reduced and control) in a fully crossed, completely randomized plot design. We found that nutrient amendment and, occasionally, insect abundance interacted with the propagule pressure of an invasive plant to alter above- and belowground structure and function at our site. Not …

Diversity Of Bacterial Communities On Sunken Woods In The Mediterranean Sea, Sandrine Bessette, Sonja K. Fagervold, Chiara Romano, Daniel Martin, Nadine Le Bris, Pierre E Galand

Journal of Marine Science and Technology

Sunken woods are very rich and diverse ecosystems supporting large macrofaunal diversity and representing a source of carbon and energy for any heterotrophic organism able to consume plant material, and those relying on specialized microbial taxa. However, relatively little is known about the microbial communities that degrade sunken woods and produce reduced compounds that serve as energy sources for chemosynthetic lifestyles. The purpose of this study was to explore the bacterial diversity developing on and within sunken woods in a NW Mediterranean submarine canyon and its adjacent slope by using 16S rRNA genes survey. We described communities from Pine wood …

Remediation Of Tetracycline From Water Sources Using Vetiver Grass (Chrysopogon Zizanioides L. Nash) And Tetracycline-Tolerant Root-Associated Bacteria, Aparupa Sengupta

Dissertations, Master's Theses and Master's Reports - Open

Antibiotics are emerging contaminants worldwide. Due to insufficient policy regulations, public awareness, and the constant exposure of the environment to antibiotic sources has created a major environmental concern. Wastewater treatment plants (WWTP) are not equipped to filter-out these compounds before the discharge of the disinfected effluent into water sources (e.g., lakes and streams) and current available technologies are not equipped to remediate these compounds from environmental sources. Hence, the challenge remains to establish a biological system to remove these antibiotics from wastewater. An invitro hydroponic remediation system was developed using vetiver grass (Chrysopogon zizanioides L. Nash) to remediate tetracycline …

Antimicrobial Properties Of Vertically Aligned Nano-Tubular Copper, Kafil Razeeb, Joanna Podporska-Carroll, Mamun Jamal, Maksudul Hassan, Michael Nolan, Declan Mccormack, Brid Quilty, Simon Newcombe, Suresh Pillai

Articles

In this work, the antimicrobial properties of vertically aligned nano-tubular Cu arrays (NT-Cu) fabricated via a template-based electrodeposition approach were investigated. The NT-Cu display good bactericidal activity against S.aureus and bacteriostatic properties against E.coli, S.sonnei, S.enterica and C.albicans. In contrast, Cu-foil electrodeposited from the same solution shows low biological activity against the same microorganisms. The antimicrobial activity of NT-Cu depends on both the type of microorganism and exposure time. After 6 hours of exposure, over 99.99% (log red = 4.43) of S.aureus population was inactivated, whereas, for E.coli, S.sonnei, S.enterica and C.albicans it was 97.8, 94.2, 89.9, and 90.3%, respectively.

Structure-Function Analysis Of Zapc, An Ftsz-Ring Stabilizer, In Escherichia Coli Cytokinesis, Lukasz Tchorzewski

Dissertations and Theses

In Escherichia coli, cell division is defined by the polymerization and constriction of a cytokinetic ring (Z ring) formed by FtsZ, a tubulin-like GTPase, at midcell. Division also involves the formation of a multi-protein complex at midcell known as the divisome. Several divisome proteins promote the assembly/disassembly processes of FtsZ, thereby exercising spatiotemporal control over division. Among FtsZ regulatory proteins are the FtsZ ringassociated proteins (Zap), which either directly or indirectly stabilize the Z-ring by increasing lateral interactions amongst FtsZ protofilaments in the Z-ring. ZapA-D are recruited during early cytokinesis and have overlapping functions in stabilizing FtsZ at midcell, but …

Microbial Communities Colonizing Leaves During Early Decomposition Stages, Stephanie Harper

Electronic Theses and Dissertations

Microbial communities associated with decaying leaves play an important role in the cycling of nutrients in stream ecosystems. In headwater streams that are deemed as heterotrophic, bacteria and fungi are main drivers of organic matter decomposition and thus partly responsible for facilitating the cycling of nutrients from leaves that fall into the stream. The main objective of this study was to compare microbial community composition between different leaf types during breakdown in stream ecosystems. To achieve this objective, I used a combination of field and laboratory trials. Field experiments were performed at the Luquillo Experimental Forest using Dacryodes excelsa and …

Microfluidic Electrical Sorting Of Particles Based On Shape In A Spiral Microchannel, John Dubose, Xinyu Lu, Saurin Patel, Shizhi Qian, Sang Woo Joo

Mechanical & Aerospace Engineering Faculty Publications

Shape is an intrinsic marker of cell cycle, an important factor for identifying a bioparticle, and also a useful indicator of cell state for disease diagnostics. Therefore, shape can be a specific marker in label-free particle and cell separation for various chemical and biological applications. We demonstrate in this work a continuous-flow electrical sorting of spherical and peanut-shaped particles of similar volumes in an asymmetric double-spiral microchannel. It exploits curvature-induced dielectrophoresis to focus particles to a tight stream in the first spiral without any sheath flow and subsequently displace them to shape-dependent flow paths in the second spiral without any …

A Simple Guanidinium Isothiocyanate Method For Bacterial Genomic Dna Isolation, Erkan Mozi̇oğlu, Müslüm Akgöz, Candan Tamerler, Zühtü Tanil Kocagöz

Turkish Journal of Biology

A high-quality and low-cost genomic DNA isolation method is needed for use in microbiology laboratories. In this study, we developed a new modified guanidinium isothiocyanate method to isolate DNA from Escherichia coli, Salmonella enterica subsp. enterica serotype Typhimurium, and Staphylococcus aureus and compared it with 4 other DNA isolation methods. The results show that the modified guanidinium isothiocyanate method developed in our laboratory is simple, fast, and inexpensive and yields DNA whose quality and quantity are similar to that of 2 commercial extraction kits but far better than 2 conventional DNA extraction methods used for comparison.

Effect Of Prey Richness On A Consumer’S Intrinsic Growth Rate, Brian J. Darby, Michael A. Herman

School of Biological Sciences: Faculty Publications

The intrinsic growth rate of nonselective microbivores increases asymptotically with increasing prey biomass, but we do not know how intrinsic growth rate is affected by prey richness. The objective of this experiment was to determine the effect of prey richness on the growth kinetics of nematode predators while grazing on mixed bacterial lawns. We found that the intrinsic growth rate of Caenorhabditis elegans in laboratory culture increased asymptotically with prey richness. The mechanism of this pattern was primarily due to the best available prey species in the mixture: the intrinsic growth rate of the consumer feeding on a mixture of …