Microbiology Commons^™

The Impact Of Socs1 And Socs3 Peptide Mimetics On Rho And Cdc42 Proteins Expression, F-Actin Cytoskeleton Rearrangements, And Cytokines Production Of Uninfected And Hsv-1 Infected M1 And M2 Raw 264.7 Murine Macrophages, Maha A. Elwardany

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The immune system plays an essential role in the pathogenesis of HSV-1 during the lytic phase of the disease, orchestrating the inflammatory response, retaining the virus in its latent phase and preventing the recurrence of HSV-1 infection. Macrophages display a vital role in the innate and adaptive immune responses during multiple phases of HSV-1 infection. Polarized macrophages are categorized into two distinct classes with diverse functions. The classically activated M1 can engulf and destroy the microbial agents, produce proinflammatory cytokines, and participate in the pathogenesis of many inflammatory diseases. The alternatively activated M2 induces anti-inflammatory mediators and stimulates tissue remodeling …

Effect Of Exposure Of Raw264.7 Macrophages To Salmonella Typhimurium Components On Cell Viability, Cytoskeleton Re-Arrangement And Cytokine Secretion, Khalid Abdullah Alyahya

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Innate immune system plays an important role in individual's protection against pathogens and in activation of adaptive immune system. Utilizing RAW 264.7 murine macrophages as an innate immune response representative in this study, we analyzed the effect of invasive pathogen's components (e.g. flagellin) on the arrangement of macrophage's cytoskeleton, on viability of immune cells and on secretion of pro-inflammatory and anti-inflammatory cytokines and on fluorescence intensity of cytoskeleton after rearrangement. Additionally, we studied the similarity and differences between bacterial (Salmonella typhimurium) and synthetic TLR4 agonist (synthetic lipid-A) on viability, fluorescence intensity, cytokine secretion, and cytoskeleton rearrangements. Similarly, we studied the …

A Novel Molecular Relationship Between Parn And Pld That, When Deregulated, Contributes To The Aggressive Phenotype Of Breast Cancer Cell Lines., Taylor Elaine Miller

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The removal of mRNA transcript poly(A) tails by 3'-5' exonucleases is the rate-limiting step for controlled mRNA decay in eukaryotes. Poly(A)-specific ribonuclease (PARN) is one such exonuclease that degrades poly(A) tails, and although its in vitro activity is well-characterized, PARN’s patho-physiological roles in the cell are not well understood. Prior studies have found a possible role for PARN in cancer, in that PARN expression levels in human breast cancer tissues are often decreased compared to normal control tissues. Indeed, data mined from the ONCOMINE cancer array database showed that PARN is downregulated in patient invasive breast carcinoma samples compared to …

Antimicrobial Activity Of Fractionated Borohydride-Capped And Electrochemical Colloidal Silver, Marjorie M. Markopoulos

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Silver nanoparticles (AgNPs) and ionic silver (Ag+) are known to be broad-spectrum antimicrobial agents. Recent studies show these agents may be an alternative to the most widely used drinking water disinfectant, chlorine. Chlorine is a toxic industrial chemical with a lethal concentration of 430 ppm after 30 minutes. Additionally, chlorine can react with naturally occurring materials to produce a number of disinfection byproducts such as chloroform and trihalomethanes. Some of these byproducts pose cancer risks in addition to other negative impacts to human health. These would be eliminated with the use of Ag+ or AgNPs. The main goal of this …

Season, But Not Symbiont State, Drives Microbiome Structure In The Temperate Coral Astrangia Poculata., Koty H. Sharp, Zoe A. Pratte, Allison H. Kerwin

Arts & Sciences Faculty Publications

BACKGROUND: Understanding the associations among corals, their photosynthetic zooxanthella symbionts (Symbiodinium), and coral-associated prokaryotic microbiomes is critical for predicting the fidelity and strength of coral symbioses in the face of growing environmental threats. Most coral-microbiome associations are beneficial, yet the mechanisms that determine the composition of the coral microbiome remain largely unknown. Here, we characterized microbiome diversity in the temperate, facultatively symbiotic coral Astrangia poculata at four seasonal time points near the northernmost limit of the species range. The facultative nature of this system allowed us to test seasonal influence and symbiotic state (Symbiodinium density in the coral) on microbiome …

Amixicile Inhibits Anaerobic Bacteria Within An Oral Microbiome Derived From Patients With Chronic Periodontitis, Kane Ramsey

Theses and Dissertations

Periodontitis is a chronic inflammatory disease caused by pathogenic bacteria residing in a complex biofilm within a susceptible host. Amixicile is a non-toxic, readily bioavailable novel antimicrobial that targets strict anaerobes through inhibition of the activity of Pyruvate Ferredoxin Oxidoreductase (PFOR), a major enzyme mediating oxidative decarboxylation of pyruvate. Our study aimed to evaluate the efficacy of amixicile, when compared to metronidazole, in inhibiting the growth of bacteria present in a microbiome harvested from patients with chronic periodontitis.

Plaque samples were harvested from patients with severe chronic periodontitis and cultured under anaerobic conditions. The microbiomes were grown in the presence …

What's In A Name? New Bacterial Species And Changes To Taxonomic Status From 2012 Through 2015, Erik Munson, Karen C. Carroll

Clinical Lab Sciences Faculty Research and Publications

Technological advancements in fields such as molecular genetics and the human microbiome have resulted in an unprecedented recognition of new bacterial genus/species designations by the International Journal of Systematic and Evolutionary Microbiology. Knowledge of designations involving clinically significant bacterial species would benefit clinical microbiologists in the context of emerging pathogens, performance of accurate organism identification, and antimicrobial susceptibility testing. In anticipation of subsequent taxonomic changes being compiled by the Journal of Clinical Microbiology on a biannual basis, this compendium summarizes novel species and taxonomic revisions specific to bacteria derived from human clinical specimens from the calendar years 2012 through …

A Rare Case Of Erythema Elevatum Diutinum Presenting As Diffuse Neuropathy, G H. Nguyen, E L. Guo, D Norris

Faculty, Staff and Students Publications

No abstract provided.

Studies Relating Pqq Biosynthesis To Putative Peptidases And Operon Structure In Pseudomonas Species, Benjamin Diaz

Theses and Dissertations--Plant and Soil Sciences

Several bacteria isolated from the broccoli rhizosphere were assayed to compare their ability to solubilize phosphate and release pyrroloquinoline quinone (PQQ) into the surrounding media. Subsequently, their genomes were sequenced and analyzed for PQQ biosynthesis operon structure. PQQ biosynthesis genes pqqA-F were found in all isolates. The order of PQQ biosynthesis genes and predicted amino acid sequences were compared to each other and the host’s ability to solubilize phosphate and release PQQ. In all Pseudomonas species, two putative protease genes, pqqF, and pqqG, flanked the canonical pqqA-pqqE biosynthesis operon. No mechanistic studies have confirmed the function of …

Using Extremophile Bacteriophage Discovery In A Stem Education Professional Development Partnership To Explore Model Classroom Research Experiences Integrating The Three Dimentions Of The Next Generation Science Standards, Carrie L. Boudreau Ms

All Student Scholarship

The National Research Council’s (NRC) A Framework for K-12 Science Education: Practices, Crosscutting Concepts, and Core Ideas describes a vision of what it means to be proficient in science. The project discussed in this thesis was developed with a NIH SEPA Grant 8R25OD010937 to the Virology and Electron Microscopy Laboratory at the University of Southern Maine (USM) under the direction of Dr. S. Monroe Duboise. The goal of the project was to explore using discovery of extreme environment bacteria and their bacteriophages as a model for using the three dimensions of learning to teach Next Generation Science Standards (NGSS). Specifically, …

Carotenoids And Metabolism Of The Green Microalga Chlorococcum Sp. 8367re Under Stress Conditions, Kantima Janchot

Chulalongkorn University Theses and Dissertations (Chula ETD)

Green microalgae are one of the natural resources for productions of various and beneficial bioactive compounds, such as UV-screening compounds and carotenoids. This study focuses on the changes of carotenoids and metabolisms in the green microalga Chlorococcum sp. 8367RE under stress conditions. The results showed that stresses by salt, light, drought, and nitrogen starvation affected on alterations of morphological characteristics. Interestingly, size of cells culturing under salt stresses dramatically increased. It should be noted that KCl stress caused the enlargement of cell sizes approximately 5 folds. Carotenoids were identified and quantified by using ultra-high performance liquid chromatography (UHPLC) and mass …

Effects Of Fertilizer And Shade Management On Nitrogen Mineralization, Nitrifying Microbial Abundance And Nitrogen-Fixing Capacity Of Erythrina Poeppigiana In Coffee (Coffea Arabica) Agroforestry Systems In Costa Rica, Stuart E. Barker Iii

College of Graduate Studies: Theses & Dissertations

Worldwide chemical fertilizer use has increased by four times during the last 50 years. Conventional agricultural systems have a high nitrifying nature, resulting in a loss of nearly 70% of overall nitrogen (N) fertilizer inputs, an estimated economic loss of $81 billion. Over application of fertilizer is rampant in tropical developing nations in Central America, where coffee is major crop. Agroforestry offers ecologically sustainable land management strategies that promote the provision of ecosystem services such as, protection of biodiversity, climate change mitigation, and water and soil regulation. When legume trees are incorporated as the shade tree in coffee production, direct …

Papillary Craniopharyngioma: A Clinicopathologic Study Of A Rare Entity From A Major Tertiary Care Center In Pakistan, Muhammad Usman Tariq, Nasir Ud Din, Zubair Ahmad, Wasim Memon

Department of Pathology and Laboratory Medicine

Background: Papillary craniopharyngioma (PCP) are uncommon variants of craniopharyngiomas (CP), which are benign epithelial neoplasms of the sellar and suprasellar region. Histologically, PCPs are typically composed of well-differentiated stratified squamous epithelium; however, focal variations are not uncommon. A distinction from other lesions of the region, despite being difficult to achieve due to the overlapping radiological and clinical features, is important for adequate treatment to be administered.
Objective: Our aim was to study the clinical and histological features of PCP with emphasis on features that are helpful in its distinction from other lesions that are similar in appearance.
Materials and Methods: …

Controlling Brochothrix Thermosphacta As A Spoilage Risk Using In Package Atmospheric Cold Plasma, Apurva Patange, Daniela Boehm, Carmen Bueno-Ferrer, Patrick Cullen, Paula Bourke

Articles

Brochothrix thermosphacta is a predominant spoilage microorganism in meat and its control in processing environments is important to maintain meat product quality. Atmospheric cold plasma is of interest for control of pathogenic and spoilage microorganisms in foods. This study ascertained the potential of dielectric barrier discharge atmospheric cold plasma (DBD-ACP) for control of B. thermosphacta in response to key parameters such as treatment time, voltage level, interactions with media composition and post treatment storage conditions. Challenge populations were evaluated as suspensions in PBS, as biofilms in meat model medium and surface attached on raw lamb chops under MAP.

ACP treatment …

Eukaryotic Microbes, Principally Fungi And Labyrinthulomycetes, Dominate Biomass On Bathypelagic Marine Snow, Alexander B. Bochdansky, Melissa A. Clouse, Gerhard J. Herndl

OES Faculty Publications

In the bathypelagic realm of the ocean, the role of marine snow as a carbon and energy source for the deep-sea biota and as a potential hotspot of microbial diversity and activity has not received adequate attention. Here, we collected bathypelagic marine snow by gentle gravity filtration of sea water onto μm filters from similar to 1000 to 3900 m to investigate the relative distribution of eukaryotic microbes. Compared with sediment traps that select for fast-sinking particles, this method collects particles unbiased by settling velocity. While prokaryotes numerically exceeded eukaryotes on marine snow, eukaryotic microbes belonging to two very distant …

Characterization Of Phytocystatin-Like Cysteine Protease Inhibitors Of Trichomonas Vaginalis, Ryan Michael John Faucher

University of the Pacific Theses and Dissertations

Trichomoniasis is a common STD caused by the parasitic protozoan Trichomonas vaginalis. The parasite is estimated to have infected roughly 3.7 million Americans. Complications from trichomoniasis can lead to cervical cancer in women and prostate cancer in men. One of the mechanisms of the parasite employs is using cysteine proteases to break down the cellular matrix of its host. However, three endogenous phytocystatin-like protease inhibitors have been found within the parasite’s genome. By recombinantly expressing these cystatins we have been able to test their ability to inhibit cysteine proteases such as papain and those found in T. vaginalis to find …

Association Of Gut Luminal Metabolites And Allergic Responses, Ghaith Mohammed Fallata

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Allergy is a global health problem, affecting more than 40% of the world population. Allergy is often associated with a dysregulation of the immune system that becomes overactive against allergens. Several genes are known to be important for the proper homeostasis of the immune system in the epithelial tissues, and the loss of function of genes such as IKKß or SOX9 impacts the interaction between external stimuli and the host. Many of the allergic responses are triggered through the regulatory cascade governed by transcriptional factor NF-κB. Regulation of NF-κB activity is complex, involves several alternative routes, and is also influenced …

Detection Of Antibiotic Resistance Loci In Wastewater And Fresh Water Samples, Mohammed Hamed Almalki

Masters Theses

Proper treatment of municipal wastewater is important not only for prevention of eutrophication but also for public health concerns. One consideration for wastewater treatment is the presence of organisms carrying antibiotic resistance genes. If these organisms survive the wastewater treatment process and are released into the streams, they can pose significant risks to public health. In addition, their presence also raises concerns for lateral gene transfer events at the wastewater plant. The spread of antibiotic loci has a major impact in public health and clinical therapy because resistant organisms render conventional treatments of important illnesses difficult. Beta-lactam drugs are known …

Characterization Of A Putative Hemolysin Expressed By Sneathia Amnii, A Preterm Birth-Associated Pathogen, Lizette Carrasco, Kimberly Jefferson

Undergraduate Research Posters

The gram-negative bacteria Sneathia amnii is a poorly-characterized commensal of the female urogenital tract frequently associated with adverse clinical outcomes such as bacterial vaginosis (BV), amnionitis, and preterm labor. To investigate its potential role in virulence, we sought to identify and characterize virulence determinants produced by S. amnii in an effort to better understand the pathogenesis of infectious preterm birth. Through sequencing of the Sn35 genome (type strain of S. amnii), we identified two genes with amino acid sequence similarity and structural similarity to the filamentous hemagglutinin (FHA) protein of Bordetella pertussis and its Type Vb transporter. Because S. amnii …

A Nutrient-Regulated Cyclic Diguanylate Phosphodiesterase Controls Clostridium Difficile Biofilm And Toxin Production During Stationary Phase, Erin B. Purcell, Robert W. Mckee, David S. Courson, Elizabeth M. Garrett, Shonna M. Mcbride, Richard E. Cheney, Rita Tamayo

Chemistry & Biochemistry Faculty Publications

The signaling molecule cyclic diguanylate (c-di-GMP) mediates physiological adaptation to extracellular stimuli in a wide range of bacteria. The complex metabolic pathways governing c-di-GMP synthesis and degradation are highly regulated, but the specific cues that impact c-di-GMP signaling are largely unknown. In the intestinal pathogen Clostridium difficile, c-di-GMP inhibits flagellar motility and toxin production and promotes pilus-dependent biofilm formation, but no specific biological functions have been ascribed to any of the individual c-di-GMP synthases or phosphodiesterases (PDEs). Here, we report the functional and biochemical characterization of a c-di-GMP PDE, PdcA, 1 of 37 confirmed or putative c-di-GMP metabolism proteins …

Comparing An Atomic Model Or Structure To A Corresponding Cryo-Electron Microscopy Image At The Central Axis Of A Helix, Stephanie Zeil, Julio Kovacs, Willy Wriggers, Jing He

Computer Science Faculty Publications

Three-dimensional density maps of biological specimens from cryo-electron microscopy (cryo-EM) can be interpreted in the form of atomic models that are modeled into the density, or they can be compared to known atomic structures. When the central axis of a helix is detectable in a cryo-EM density map, it is possible to quantify the agreement between this central axis and a central axis calculated from the atomic model or structure. We propose a novel arc-length association method to compare the two axes reliably. This method was applied to 79 helices in simulated density maps and six case studies using cryo-EM …