Microbiology Commons^™

Attached Algae As An Indicator Of Water Quality: A Study Of The Viability Of Genomic Taxonomic Methods, Allison R. Wood

Honors Theses and Capstones

This research involved evaluating algae as an indicator of water quality in New Hampshire's rivers, with a focus on the Great Bay Estuary. The project had three main goals. First, determining whether or not algae would work as an indicator of water quality in the great bay ecosystem, an environment where tidal currents are strong and water composition is mixed. The second goal was to compare traditional microscopic methods of taxonomy with emerging genomic methods, increasing the economic viability of attached algae monitoring. The third project goal, still underway, is to evaluate massive amounts of genomic data from the Great …

Antibiotic Efficacy And Interaction In Escherichia Coli During Varying Nutrient Conditions, Kristina K. Millar

Scripps Senior Theses

Due to the recent rise in antibiotic resistant pathogens, and the difficulties surrounding the quest for new antibiotics, many researchers have started revisiting antibiotic interactions in hopes of finding new treatment options. The primary outcome of this project was to examine the efficacy of concomitant antibiotic use under varying nutrient conditions, to identify variations in antibiotic interactions. Antibiotic interactions were studied, utilizing E. coli as a model bacterial system, grown in four different media types. E. coli cultures were treated with streptomycin, tobramycin, erythromycin, and amikacin individually and in a pairwise fashion at varying doses. We found that at least …

Humboldt Journal Of Microbiology: Volume 18, Number 1- May 2016, Press Humboldt

Humboldt Journal of Microbiology

No abstract provided.

Synergistic Growth In Bacteria Depends On Substrate Complexity, Yi-Jie Deng, Shiao Y. Wang

Faculty Publications

Both positive and negative interactions among bacteria take place in the environment. We hypothesize that the complexity of the substrate affects the way bacteria interact with greater cooperation in the presence of recalcitrant substrate. We isolated lignocellulolytic bacteria from salt marsh detritus and compared the growth, metabolic activity and enzyme production of pure cultures to those of three-species mixed cultures in lignocellulose and glucose media. Synergistic growth was common in lignocellulose medium containing carboxyl methyl cellulose, xylan and lignin but absent in glucose medium. Bacterial synergism promoted metabolic activity in synergistic mixed cultures but not the maximal growth rate (μ). …

The Impact Of Oxygen On Bacterial Enteric Pathogens, Nathan Wallace, Ashley N. Zani, Elizabeth A. Abrams, Yvonne Sun

Biology Faculty Publications

Bacterial enteric pathogens are responsible for a tremendous amount of foodborne illnesses every year through the consumption of contaminated food products. During their transit from contaminated food sources to the host gastrointestinal tract, these pathogens are exposed and must adapt to fluctuating oxygen levels to successfully colonize the host and cause diseases. However, the majority of enteric infection research has been conducted under aerobic conditions. To raise awareness of the importance in understanding the impact of oxygen, or lack of oxygen, on enteric pathogenesis, we describe in this review the metabolic and physiological responses of nine bacterial enteric pathogens exposed …

Characterization Of Insertion Sequence Is605 In Halanaerobium Hydrogeniformans, Michael C. Sadler

Masters Theses

"Insertion sequences are the smallest prokaryotic transposable elements. These genes play a significant evolutionary role by promoting genome plasticity. Insertion sequences are highly diverse elements that have largely been uncharacterized. As such, the ability to accurately identify, annotate, and infer genomic impact of insertion sequences is lacking. The study of new insertion sequences contributes knowledge to their annotation and evolution. Halanaerobium hydrogeniformans is a unique organism with an abnormally high number of insertion sequences. A family of insertion sequences, IS200/605, showed several interesting distinctions from other elements in the genome, including severe open reading frame degradation, and was characterized in …

Frequency And Etiology Of Community-Acquired Bloodstream Infection In Hospitalized Febrile Children, Tufail Soomro, Shiyam Sunder Tikmani, Sumera Aziz Ali

Community Health Sciences

Background: Blood stream infection is a serious problem that needs immediate attention and treatment. We aim to identify the frequency of common organisms in blood culture of febrile pediatric patients so that empirical antibiotic therapy can be started timely.
Methods: This cross-sectional study was conducted in pediatric ward Civil Hospital Sukkur from 1st May 2013 to 31st October 2014. Children of both genders who are between the age of one month to 15 years admitted to the pediatric ward with a fever of > 38.0 c and with a history of fever ˃ two days and whose blood culture has been …

The Expression Of Major Histocompatibility Class I And Major Histocompatibility Class Ii On Macrophages In The Presence Of Aryl Hydrocarbon Antagonist (Ch-223191), Caitlin Wilson

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Macrophages are crucial for ridding the body of debris and foreign cells. The aryl hydrocarbon receptor (AhR) also plays a critical role in immunity. This study examined the effect of the AhR on the expression of major histocompatiability complex class I (MHCI) and MHC class II (MHCII) in two murine macrophage cell lines. This study used Raw264.7 and J774A.1 murine macrophage cell lines. The Raw264.7 cells are from male BALB/c mice while the J774A.1 cells are from female BALB/cN mice. The addition of the AhR anatagonist CH-223191 (AhRa) showed that the AhR does not significantly impact MHCI expression. However, MHCII …

Anaplasma Marginale Actively Modulates Vacuolar Maturation During Intracellular Infection Of Its Tick Vector, Dermacentor Andersoni, Foregivemore Magunda, Chelsea Wright Thompson, David A. Schneider, Susan M. Noh

Biological Sciences Faculty Publications

ABSTRACT Tick-borne transmission of bacterial pathogens in the order Rickettsiales is responsible for diverse infectious diseases, many of them severe, in humans and animals. Transmission dynamics differ among these pathogens and are reflected in the pathogen-vector interaction. Anaplasma marginale has been shown to establish and maintain infectivity within Dermacentor spp. for weeks to months while escaping the complex network of vacuolar peptidases that are responsible for digestion ofthe tick blood meal. How this prolonged maintenance of infectivity in a potentially hostile environment is achieved has been unknown. Using the natural vector Dermacentor andersoni, we demonstrated that A. marginale …

Characterizing The Role Of The Fact Complex In Hiv-1 Infection, Angelica Patricia Lopez

Open Access Theses & Dissertations

The lens epithelium-derived growth factor p75 (LEDGF/p75) is a chromatin-bound protein essential for efficient lentiviral integration. Knockdown of this protein severely affects HIV-1 integration levels and thus itâ??s replication. Genome-wide studies have located LEDGF/p75 inside actively transcribed genes where it mediates lentiviral integration. Although this is clearly established, the molecular mechanisms of LEDGF/p75 in HIV-1 infection remain in part elusive.

Using protein-protein interaction assays, we demonstrated that LEDGF/p75 complexes with a chromatin remodeling complex, Facilitates Chromatin Transcription (FACT), a heterodimer of the structure specific recognition protein 1 (SSRP1) and the human homolog of suppressor of Ty 16 (hSpt16). The FACT …

Defining And Characterizing The Step In The Hiv-1 Viral Life Cycle Affected By Fullerene Derivatives, Zachary Sean Martinez

Open Access Theses & Dissertations

Fullerene derivatives, both C60 and C70, were synthesized and characterized to test their activity against HIV-1 infection. The derivatives tested have previously been reported to inhibit HIV-1 replication and/or in vitro activity of reverse transcriptase. It was found that viruses produced in the presence of low micromolar concentrations of most of these fullerene derivatives exhibit a reduction in viral infectivity greater than 99%. Quantification of virion-associated viral RNA and p24 indicates that RNA packaging and viral production were unremarkable in these viruses. These compounds did not affect infectivity of mature virions, indicating no effect on the early steps of the …

Determining The Role Of Poly [Adp-Ribose] Polymerase 1 (Parp-1) In Retroviral Infection, Luis Valdes Rodriguez

Open Access Theses & Dissertations

Possible links between PARP-1 and HIV-1 have been previously reported but the role of this protein during viral infection has remained elusive. Based on the high evolutionary conservation of PARP-1, from Drosophila to humans, we have been able to counteract the difficulties related with the functional redundancy manifested in the PARP family by studying the influence of PARP-1 on the expression of an endogenous retrovirus using the chicken B lymphoblastoid cell line DT40, this cell line exhibits low PARP-1 functional redundancy and is viable after PARP-1 knockout. We have determined that the transcription level of the endogenous retrovirus RAV-1 is …

Effects Of Epichloë Coenophiala−Tall Fescue Symbiosis On Plant-Microbe-Soil Interactions In A Temperate Pasture, Lindsey C. Slaughter

Theses and Dissertations--Plant and Soil Sciences

Plants interact in myriad ways with microorganisms to influence ecosystem processes such as nutrient cycling, which can regulate ecosystem response to global change. One important plant-microbe symbiosis occurs between cool-season grasses and asexual fungal Epichloë endophytes, such as tall fescue (Schedonorus arundinaceus) and Epichloë coenophiala. Because the common toxic strain of the endophyte (CTE) harms grazing livestock, non-livestock toxic endophyte (NTE) strains have been developed and are increasingly deployed in pastures. Little is known about how these symbioses impact other plant-microbe interactions and microbe-mediated soil processes in grassland ecosystems. I conducted three studies to determine how E. …

Screening For Pathogenic Escherichia Coli In The Chattahoochee River, Columbus, Georgia, Micah A. Staples

Theses and Dissertations

Escherichia coli testing is frequently used to indicate the possible presence of harmful pathogens, but E. coli itself can be pathogenic. Serotype 0157:H7, enterohemorrhagic E. coli, is likely the most medically important pathogenic strain of E. coli in the United States. In this study, we surveyed for 0157:H7 and three strains of another pathogenic subtype: enterotoxigenic E. coli. We isolated E. coli colonies from samples taken from the Chattahoochee River in Columbus, Georgia at two different locations, above and below wastewater outputs. We used PCR to test for the individual subtypes and then used a nested PCR protocol …

Cell Viability, Cytoskeleton Organization And Cytokines Secretion Of Raw 264.7 Macrophages Exposed To Gram-Negative Bacterial Components, Ali Awadh Alshehri

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Macrophages play an important role in innate immunity by controlling cellular responses. In this study, the effects of gram-negative bacterial components (Flagellin, lipoprotein, lipopolysaccharides (LPS), outer membrane proteins-A (OMP-A) and peptidoglycan) were determined on cell viability, morphology, cytoskeletal filament and cytokines secretion of murine RAW 264.7 macrophages at 24 hours. The effect of LPS, flagellin and peptidoglycan from gram negative bacteria on viability murine RAW 264.7 macrophages were evaluated using different concentrations (1, 5 and 10 µg/ml). Cells stimulated with LPS displayed ~ 2-fold decrease (P=0.001) in cell viability compared to control cells at 24 hours whereas cells stimulated with …

The Expression Of Dopamine-Related Genes And Behavioral Performance In Mice, Victoria Lynne Dershem

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While the neurotransmitter dopamine has been well-studied for its role in mood regulation and activation of the intrinsic reward pathway, several psychiatric disorders linked to dopamine are also known to cause memory impairment, a phenomenon which has attracted much less attention. In the current study, whole-transcriptome RNA sequencing was performed, and transcript levels of several dopamine-related genes were compared to results of behavioral assays designed to test spatial and emotional memory, as well as anxiety. The results suggest a positive relationship between expression level of Nurr1, a nuclear receptor known to initiate transcription of genes necessary for dopaminergic signaling, …

Development And Validation Of Virus And Ebola Misconceptions Assessment (Viremia): Ebola Virus Misconceptions In College Students, Michele Miller

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In this study an assessment (VirEMiA) on college students' knowledge and misconceptions of the Ebola virus was created and validated. VirEMiA was then used to determine what misconceptions college students have about Ebola, if there is a difference in misconceptions between students with and without a strong science background, and if Just-in-Time Teaching (JiTT) increases students' knowledge of Ebola and decreases their misconceptions. VirEMiA was shown to be a valid and reliable assessment whether confidence was integrated (seprel=0.97) or not (seprel=0.98), and for measuring misconceptions (seprel=0.97). If psychology and nursing majors were considered to have a strong background in science, …

Relationships Between Fecal Indicator Bacteria And Environmental Factors At Edgewater Beach, Anna M. King

Williams Honors College, Honors Research Projects

To provide more timely estimates of indicator bacteria concentrations in recreational waters, environmental agencies are using predictive models to supplement conventional bacteria enumeration methods. As a tool to develop predictive models, correlational relationships between variables can be examined, to determine the statistical significance of explanatory variables. Prior research at Lake Erie beaches suggests that environmental conditions such as average wave height, rainfall, turbidity, and water temperature may demonstrate a strong relationship to concentrations of fecal indicator bacteria Escherichia coli and Enterococcus faecalis (enterococci). These relationships were examined at Edgewater Beach in Cleveland, Ohio, using statistical correlation tests on data collected …

Metabolism Of Herpes Simplex Virus 1 Infected Raw 264.7 Macrophages, Mary K. Jenkins

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Macrophages are immune cells that phagocytize pathogens and act as antigen presenting cells. Macrophages are critical in regulating the adaptive immune response and play a key role in neutralizing infection. Macrophages exhibit a variety of phenotypes which have different energy requirements. In the case of HSV-1 infection the virus has been shown to alter metabolic processes of its host. Utilizing a XF24 Extracellular Flux Analyzer the metabolic activity of M0, M1, and M2 (IL-4, IL-13, and IL-10) RAW 264.7 macrophages was quantified for both uninfected cells and in response to HSV-1 infection. The analysis showed uninfected M0 and M2 (IL-4, …

The Anti-Apoptotic Effect Of Hsv-1 On Murine Macrophages: Raw 246.7 Murine Macrophage Cell Line, Mofeda Abdussalam Alhanghari

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Herpes simplex virus type 1 (HSV-1) is a worldwide pathogen that affects humans and has the ability to establish a latent state of infection in the sensory nerve ganglia after primary infection of epithelial cells (Boutell and Everett, 2003). HSV-1 is a very contagious virus, which can be transmitted from person to person and cause cold sores in the infected person. Rarely, infection can lead to more serious complications, such as encephalitis. Most HSV-1 infections usually occur in childhood with lifelong potential for symptomatic or asymptomatic viral shedding episodes (Looker et al., 2015). HSV- 1 infects 60%-80% of people throughout …