Environmental Microbiology and Microbial Ecology Commons^™

The Influence Of Hydrogeomorphology, Soil Redox Conditions, And Salinity On The Spatial Zoning Of Saltgrass, Salt Rush, And Cattails In Scotts Creek Marsh, Swanton Pacific Ranch, Ca, Mark D. Gormley

Master's Theses

Scotts Creek Marsh (SCM) is a small coastal wetland ecosystem in Davenport, CA. The vegetation of SCM is dominated by three halophytic zones comprised of saltgrass, salt rush, cattails. The objectives of the study were (i) to investigate the variables that influence the zoning of the three dominant halophyte communities in SCM and (ii) to the test the effectiveness of Indicator of Reduction in Soil (IRIS) tubes to indicate the reduction of S. The study examined the following parameters from April 6 to July 21, 2013: (i) the HGM of Scotts Creek Marsh, (ii) soil oxidation and reduction (redox) conditions, …

Taxis Toward Hydrogen Gas By Methanococcus Maripaludis, Kristen A. Brileya, James M. Connolly, Carey Downey, Robin Gerlach, Matthew W. Fields

Biology Faculty Publications and Presentations

Knowledge of taxis (directed swimming) in the Archaea is currently expanding through identification of novel receptors, effectors, and proteins involved in signal transduction to the flagellar motor. Although the ability for biological cells to sense and swim toward hydrogen gas has been hypothesized for many years, this capacity has yet to be observed and demonstrated. Here we show that the average swimming velocity increases in the direction of a source of hydrogen gas for the methanogen, Methanococcus maripaludis using a capillary assay with anoxic gas-phase control and time-lapse microscopy. The results indicate that a methanogen couples motility to hydrogen concentration …

National Park Service Cave Ecology Inventory And Monitoring Framework, Gretchen M. Baker, Steven J. Taylor, Shawn Thomas, Rick Olson, Kathy Lavoie, Marie Denn, Steven Thomas, Hazel Barton, Kurt Helf, Rene Ohms, Joel Despain, Jim Kennedy, David Larson

National Cave and Karst Management Symposium 2013

A team developed the Cave Ecology Inventory and Monitoring Framework for National Park Service (NPS) units. It contains information for NPS cave managers across the United States to determine how to inventory and monitor cave ecology. Due to the wide geographical scope of NPS caves and their many different types, the document does not prescribe exact protocols. Instead, it provides guidance for what types of inventory and monitoring are possible, a framework for deciding how to prioritize inventory and monitoring activities, and references to specific protocols that are already in place at NPS cave parks.

Keywords: cave ecology, cave microbiology, …

Wash Education: Need For More Than Water Treatment For Floating Villages In Cambodia, Kevin Curry

2013 New England Association for Asian Studies Conference

Point of use (POU) water treatment systems are widely used around the world to provide microbiologically safe drinking water in developing countries. Work done in Cambodia by Brown et al. (2007) and Liang et al. (2010) have documented ceramic and biosand filters as cost effective point of use treatment systems capable of removing over 95% E. coli bacteria when properly used and maintained. Bridgewater State University and Water for Cambodia (WfC) explored using BioSand filters (BSF) to provide microbiologically safe drinking water for people in the Moat Khla floating village on the Tonle Sap Lake in Siem Reap Province. All …

Mycological Study For A Management Plan Of A Neotropical Show Cave (Brazil), Erika Linzi Silva Taylor, Maria Aparecida De Resende Stoianoff, Rodrigo Lopes Ferreira

International Journal of Speleology

Caves are stable environments with characteristics favoring the development of microorganisms. The allocthonous input of organic matter and microbes into the warm Neotropical caves may favor the development of filamentous fungi, including pathogenic species. Histoplasma capsulatum is a pathogenic species commonly found in caves and associated with bat and bird guano. Many Brazilian caves have been historically visited due to scenic and religious tourism. The objective of this study was to perform a microbiology study for a management plan of a show cave in Brazil, focusing on the presence and distribution of pathogenic and opportunistic fungi in the cave. Statistics …

Climate Change From Oxygen Isotopic Variation Of Pore Water From Sediments In Punderson Lake, Northeast Ohio, Rachel Daley, Fasong Yuan

Undergraduate Research Posters 2013

The environment in Ohio has changed over time. The hydroclimate, which is the climate of the water, shows changes from the Industrial Revolution to the present. Evidence for these changes can be found in levels of δ18O and δ2H isotopes in the layers of sediment and water in the lakes of Northeast Ohio. Mass spectrometry can be used to test the levels of δ18O and δ2H isotopes from pore water samples within sediment cores. In this study, surface soil and water samples were collected from cores in Punderson Lake at Punderson State Park in Newbury, Ohio. Pore water was extracted …

Effects Of Environmental Factors And Nutrient Availability On The Biochemical Composition Of Algae For Biofuels Production: A Review, Ankita Juneja, Ruben Michael Ceballos, Ganti S. Murthy

Biological Sciences Faculty Publications and Presentations

Due to significant lipid and carbohydrate production as well as other useful properties such as high production of useful biomolecular substrates (e.g., lipids) and the ability to grow using non-potable water sources, algae are being explored as a potential high-yield feedstock for biofuels production. In both natural and engineered systems, algae can be exposed to a variety of environmental conditions that affect growth rate and cellular composition. With respect to the latter, the amount of carbon fixed in lipids and carbohydrates (e.g., starch) is highly influenced by environmental factors and nutrient availability. Understanding synergistic interactions between multiple environmental variables and …

Epilithic And Aerophilic Diatoms In The Artificial Environment Of Kungsträdgården Metro Station, Stockholm, Sweden, Lena Norbäck Ivarsson, Magnus Ivarsson, Johannes Lundberg, Therese Sallstedt, Catarina Rydin

International Journal of Speleology

The Kungsträdgården metro station is an artificial and urban subsurface environment illuminated with artificial light. Its ecosystem is almost completely unknown and as a first step to better understand the biology and rock wall habitats the diatom flora was investigated. A total of 12 species were found growing on the rock walls of Kungsträdgården metro station. The results show the diatom flora in Kungsträdgården to be dominated by e.g. Diadesmis contenta, Diadesmis perpusilla, Pinnularia appendiculata, Nitzschia amphibia, Nitzschia sinuata and Diploneis ovalis. One species, Caloneis cf. aerophila, has never been reported from Sweden before. …

Life Support: Long Term Storage Of Solid Waste In An Enclosed Membrane System, Emmy O. Trieu, Michael Flynn, Rocco Mancinelli

STAR Program Research Presentations

In deep space missions, maintaining life support is of the utmost priority. In such a closed system, human waste must be stored and treated. Simulated feces (ersatz) will be inoculated with microbes representing normal fecal flora, mixed with urine brine and shredded refuse of products typically used in space missions. Composting methods often use alternating layers of waste with scraps of carboniferous materials (finely shredded refuse). By preparing membrane bags with a homogenized ersatz and carboniferous refuse mixture and membrane bags with alternating layers of ersatz and carboniferous refuse, it may be possible to monitor anaerobic thermophillic digestion of the …

Defining The Requirements For Early Gene Expression In Bacteriophage Hk639, Amanda L. Seaton

Masters Theses & Specialist Projects

Lambdoid phages suppress transcription termination to fully express their genes. Antitermination of early gene expression in most lambdoid phages is mediated by an interaction between the N protein and a number of host-encoded factors. Bacteriophage HK022 does not rely on a protein for antitermination. To promote full expression of early phage genes, the transcripts of the HK022 put sites interact directly with RNA polymerase to convert it to a termination resistant form. Bacteriophage HK639 also uses RNA-mediated antitermination. However, it only possesses a single put-like element in its left operon. Because most lambdoid phages, including HK022, have antiterminator elements in …

Development And Characterization Of An In Vitro Four-Species Anaerobic Dental Biofilm Model, Fernando Andrade

Dissertations and Theses (Open Access)

Dental caries is the most common chronic disease worldwide. It is characterized by the demineralization of tooth enamel caused by acid produced by cariogenic dental bacteria growing on tooth surfaces, termed bacterial biofilms. Cariogenesis is a complex biological process that is influence by multiple factors and is not attributed to a sole causative agent. Instead, caries is associated with multispecies microbial biofilm communities composed of some bacterial species that directly influence the development of a caries lesion and other species that are seemingly benign but must contribute to the community in an uncharacterized way. Clinical analysis of dental caries and …

Coccidia Of Gerbils From Mongolia, Ethan Thomas Jensen

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

In this study, gerbils collected in the Mongolia over the summers of 2009-2012 were examined for coccidia. In total, 171 gerbils of three species from 22 localities were examined for coccidia. Coccidian oocysts were identified from 21 gerbils, but those found in 1 of those gerbils were probably pseudoparasites of the host from which they were recovered. From the remaining 20 gerbils, 7 morphotypes of Eimeria and 1 morphotype of Isospora were identified. Four of the 7 morphotypes of Eimeria were attributed to new species which were described in this study. In addition, 10 previously described species of Eimeria were …

Comparative Microbial Community Composition From Secondary Carbonate (Moonmilk) Deposits: Implications For The Cansiliella Servadeii Cave Hygropetric Food Web, Annette Summers Engel, Maurizio G. Paoletti, Mattia Beggio, Luca Dorigo, Alberto Pamio, Tiziano Gomiero, Claudio Furlan, Mauro Brilli, Angelo Leandro Dreon, Roberto Bertoni, Andrea Squartini

International Journal of Speleology

The microbial diversity of moonmilk, a hydrated calcium carbonate speleothem, was evaluated from two Italian caves to provide context for the food web of highly-specialized troglobitic beetles, Cansiliella spp. (Leptodirinae), with distinctive carbon and nitrogen isotope values indicative of a novel food source. The moonmilk and associated percolating waters had low to no extractable chlorophyll, with an average organic C:N ratio of 9, indicating limited allochthonous input and a significant contribution from microbial biomass. The biomass from moonmilk was estimated to be ~10⁴ micro- and meiofaunal individuals per m² and ~10⁷ microbial cells/ml. Betaproteobacteria dominated the …

Levels And Chemodynamics Of Pesticides In Soil And Sediments At Kilombero Sugarcane Plantations And Environs, Morogoro Region, Tanzania, James T. Zacharia

Journal of Humanities and Social Sciences

metabolites in soil and sediment samples from Kilombero sugarcane plantations and environs, Morogoro Region, Tanzania. The samples were screened for 56 different pesticide residues and their metabolites using GC-ECD and GC-NPD and the results were confirmed by GC-MS. A total of 31 soil samples and 19 sediment samples were analysed in this study and a total of 16 different pesticides/metabolites were detected in soil samples; and 12 different pesticides/metabolites were detected in sediment samples. o,p’-DDT was shown to have the highest concentration of all the detected pesticides/metabolites in soil samples with a mean concentration of 21.04µg/kg d.w whereas the highest …

Escherichia Coli Strain Diversity In Humans: Effects Of Sampling Effort And Methodology, Emily R. Neal

Master's Theses

Studies investigating Escherichia coli strain diversity and demographics in human hosts are frequently inconsistent regarding sampling effort and methodology while current strain typing methods are often expensive or laborious. To rectify these inconsistencies, sampling effort was investigated by comparing the diversity of 15-isolate collections to 100-isolate collections from 3 human subjects. Temporal variation in E. coli strain diversity was also studied by collecting 15 isolates once every 6 months. Additionally, strain identification and diversity collected by different sampling methods (fecal swabs vs. anal swabs collected at different times around defecation) were compared to identify any inherent biases in sampling method. …

Aerobic Degradation Of Α-, Β-, Γ-Hexachlorocyclohexane By Narragansett Bay Bacterioplankton, Ian M. Rambo

Senior Honors Projects

Hexachlorocyclohexanes (HCHs) are a family of chlorinated organic compounds that were previously used as agricultural insecticides. HCHs are recognized as persistent organic pollutants due to their toxicity, recalcitrant properties, and tendency to bioaccumulate in food webs. Although HCH was first synthesized in 1825, its use was not widespread until the discovery of the insecticidal activity of the γ-HCH isomer in 1942. γ-HCH and its toxic waste isomers α-HCH and β-HCH were banned from production and use by the United Nations in 2009, yet these chemicals still present environmental problems due to their persistence in soils and surface waters. HCHs continue …

Litter Conditioning Is Differentially Affected By Leaf Species, Phosphorus Enrichment, And Light Availability, Erin E. Scott

Graduate Theses and Dissertations

Anthropogenic enrichment of nitrogen and phosphorus is one of the most pervasive and detrimental threats to aquatic ecosystems worldwide. In streams that rely on allochthonous basal food resources, such as leaves, nutrient pollution can result in altered food quality and decreased carbon (C) standing stocks. However, the magnitude and mechanisms of this change in quality are poorly understood. Laboratory microcosm studies were conducted to 1) quantify the response of litter C:P to a gradient of phosphorus (P) enrichment (0, 0.05, and 0.5 mg SRP/L) across leaf species with variable levels of degradability (sugar maple and oak), and 2) quantify the …

Agricultural Management And Labile Carbon Additions Affect Soil Microbial Community Structure And Interact With Carbon And Nitrogen Cycling, Sean T. Berthrong, Daniel H. Buckely, Laurie E. Drinkwater

Scholarship and Professional Work - LAS

We investigated how conversion from conventional agriculture to organic management affected the structure and biogeochemical function of soil microbial communities. We hypothesized the following. (1) Changing agricultural management practices will alter soil microbial community structure driven by increasing microbial diversity in organic management. (2) Organically managed soil microbial communities will mineralize more N and will also mineralize more N in response to substrate addition than conventionally managed soil communities. (3) Microbial communities under organic management will be more efficient and respire less added C. Soils from organically and conventionally managed agroecosystems were incubated with and without glucose (¹³C) …

Candida Albicans Czf1 And Efg1 Coordinate The Response To Farnesol During Quorum Sensing, White-Opaque Thermal Dimorphism, And Cell Death, Melanie L. Langford, Jessica C. Hargarten, Krista D. Patefield, Elizabeth Marta, Jill R. Blankenship, Saranna Fanning, Kenneth W. Nickerson, Audrey L. Atkin

Kenneth Nickerson Papers

Quorum sensing by farnesol in Candida albicans inhibits filamentation and may be directly related to its ability to cause both mucosal and systemic diseases. The Ras1-cyclic AMP signaling pathway is a target for farnesol inhibition. However, a clear understanding of the downstream effectors of the morphological farnesol response has yet to be unraveled. To address this issue, we screened a library for mutants that fail to respond to farnesol. Six mutants were identified, and the czf1/czf1 mutant was selected for further characterization. Czf1 is a transcription factor that regulates filamentation in embedded agar and also whiteto- opaque switching. We found …

Bacteriostatic Effects Of Sucralose On Environmental Bacteria, Arthur Phillip Omran Jr.

UNF Graduate Theses and Dissertations

Sucralose is a zero calorie sweetener developed and manufactured by Tate and Lyle Sweetener Company in the 1980’s. They sell the sweetener compounded with maltodextrin and dextrose under the brand name Splenda®. Sucralose was developed as a low cost artificial sweetener that is non-metabolizable in humans and can withstand changes in pH and temperature. It is not degraded by the waste water treatment process. Since the molecule can withstand heat, acidification and microbial degradation it is accumulating in the environment, and has been found in waste water, estuaries, rivers and the Gulf Stream. The highest concentration of environmental sucralose detected …