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Agricultural Soil Bacteria; A Study Of Collection, Cultivation, And Lysogeny, Katherine Elizabeth Sides 2010 University of Tennessee - Knoxville

Agricultural Soil Bacteria; A Study Of Collection, Cultivation, And Lysogeny, Katherine Elizabeth Sides

Masters Theses

The aim of this research project was to test new collection and cultivation techniques that may increase the range of cultivable diversity of soil bacteria. Fortified BioSep beads were employed in situ to capture soil bacteria, and the success of the beads was analyzed using Phylochip microarray analysis. In the cultivation phase, three different media substrates and increased incubation period were evaluated for the ability to select novel or rare bacteria. Over 700 agricultural soil bacterial isolates were classified, including a rare Gemmatimonadetes sp., a rare Verrucomicrobia sp., several Acidobacteria sp., and many novel isolates. Land management, media, and incubation …


Molecular Basis Of Corynebacterium Diphtheriae Virulence And Infection In The Caenorhabditis Elegans Model Host, Melissa M. Broadway 2010 University of Texas Graduate School of Biomedical Sciences at Houston

Molecular Basis Of Corynebacterium Diphtheriae Virulence And Infection In The Caenorhabditis Elegans Model Host, Melissa M. Broadway

The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences Dissertations and Theses (Open Access)

Corynebacterium diphtheriae is the causative agent of cutaneous and pharyngeal diphtheria in humans. While lethality is certainly caused by diphtheria toxin, corynebacterial colonization may primarily require proteinaceous fibers called pili, which mediate adherence to specific tissues. The type strain of C. diphtheriae possesses three distinct pilus structures, namely the SpaA, SpaD, and SpaH-type pili, which are encoded by three distinct pilus gene clusters. The pilus is assembled onto the bacterial peptidoglycan by a specific transpeptidase enzyme called sortase. Although the SpaA pili are shown to be specific for pharyngeal cells in vitro, little is known about functions of the three …


Functional Characterization Of Mat1-1-Specific Mating-Type Genes In The Homothallic Ascomycete Sordaria Macrospora Provides New Insights Into Essential And Nonessential Sexual Regulators, V. Klix, M. Nowrousian, C. Ringelberg, J. J. Loros 2010 Dartmouth College

Functional Characterization Of Mat1-1-Specific Mating-Type Genes In The Homothallic Ascomycete Sordaria Macrospora Provides New Insights Into Essential And Nonessential Sexual Regulators, V. Klix, M. Nowrousian, C. Ringelberg, J. J. Loros

Dartmouth Scholarship

Mating-type genes in fungi encode regulators of mating and sexual development. Heterothallic ascomycete species require different sets of mating-type genes to control nonself-recognition and mating of compatible partners of different mating types. Homothallic (self-fertile) species also carry mating-type genes in their genome that are essential for sexual development. To analyze the molecular basis of homothallism and the role of mating-type genes during fruiting-body development, we deleted each of the three genes, SmtA-1 (MAT1-1-1), SmtA-2 (MAT1-1-2), and SmtA-3 (MAT1-1-3), contained in the MAT1-1 part of the mating-type locus of the homothallic ascomycete species Sordaria macrospora. Phenotypic analysis of deletion mutants revealed …


Elevated Tumor Necrosis Factor Alpha Production Concomitant To Elevated Prostaglandin E2 Production By Trauma Patients' Monocytes, Thomas Takayama, Carol Miller-Graziano, Gyongyi Szabo 2010 University of Massachusetts Medical School

Elevated Tumor Necrosis Factor Alpha Production Concomitant To Elevated Prostaglandin E2 Production By Trauma Patients' Monocytes, Thomas Takayama, Carol Miller-Graziano, Gyongyi Szabo

Gyongyi Szabo

The level of tumor necrosis factor alpha (TNF alpha), a monokine implicated in mediating septic shock, is elevated in the blood of some patients with sepsis. Monocytes from 11 trauma patients and 11 burn patients were suboptimally stimulated with interferon gamma and muramyl dipeptide, an analogue of bacterial wall products. The patients with sepsis showed significantly greater total TNF alpha levels (secreted in combination with cell-associated) 3 days before septic episodes, as compared with normal controls (32.38 to 2231.76 ng/10(6) monocytes per milliliter, median = 121.03 ng/10(6) monocytes per milliliter; normal control: 0.00 to 18.20 ng/10(6) monocytes per milliliter, median …


Hepatitis C Core And Nonstructural 3 Proteins Trigger Toll-Like Receptor 2-Mediated Pathways And Inflammatory Activation, Angela Dolganiuc, Shilpa Oak, Karen Kodys, Douglas Golenbock, Robert Finberg, Evelyn Kurt-Jones, Gyongyi Szabo 2010 University of Massachusetts Medical School

Hepatitis C Core And Nonstructural 3 Proteins Trigger Toll-Like Receptor 2-Mediated Pathways And Inflammatory Activation, Angela Dolganiuc, Shilpa Oak, Karen Kodys, Douglas Golenbock, Robert Finberg, Evelyn Kurt-Jones, Gyongyi Szabo

Gyongyi Szabo

BACKGROUND AND AIMS: Recent evidence suggests that toll-like receptors (TLRs) recognize certain viruses. We reported that hepatitis C virus (HCV) core and nonstructural 3 (NS3) proteins activate inflammatory pathways in monocytes. The aim of this study was to investigate the role of TLRs in innate immune cell activation by core and NS3 proteins. METHODS: Human monocytes, human embryonic kidney cells transfected with TLR2, and peritoneal macrophages from TLR2, MyD88 knockout, and wild-type mice were studied to determine intracellular signaling and proinflammatory cytokine induction by HCV proteins. RESULTS: HCV core and NS3 proteins triggered inflammatory cell activation via the pattern recognition …


Microbial Fuel Cells, A Current Review, Ashley E. Franks, Kelly Nevin 2010 University of Massachusetts - Amherst

Microbial Fuel Cells, A Current Review, Ashley E. Franks, Kelly Nevin

Kelly Nevin

Microbial fuel cells (MFCs) are devices that can use bacterial metabolism to produce an electrical current from a wide range organic substrates. Due to the promise of sustainable energy production from organic wastes, research has intensified in this field in the last few years. While holding great promise only a few marine sediment MFCs have been used practically, providing current for low power devices. To further improve MFC technology an understanding of the limitations and microbiology of these systems is required. Some researchers are uncovering that the greatest value of MFC technology may not be the production of electricity but …


Increase In Isolation Of Extended Spectrum Beta Lactamase Producing Multidrug Resistant Non Typhoidal Salmonellae In Pakistan., Kauser Jabeen, Afia Zafar, Seema Irfan, Erum Khan, Vikram Mehraj, Rumina Hasan 2010 Aga Khan University

Increase In Isolation Of Extended Spectrum Beta Lactamase Producing Multidrug Resistant Non Typhoidal Salmonellae In Pakistan., Kauser Jabeen, Afia Zafar, Seema Irfan, Erum Khan, Vikram Mehraj, Rumina Hasan

Department of Pathology and Laboratory Medicine

Background:Increasing resistance to quinolones and ceftriaxone in non typhoidal Salmonellae is a global concern. Resistance to quinolone and 3rd generation cephalosporin amongst non typhoidal Salmonellae (NTS) from Pakistan has been reported in this study.

Methods:

Retrospective analysis of laboratory data was conducted (1990-2006). NTS were isolated and identified from clinical samples using standard microbiological techniques. Antimicrobial susceptibility testing was performed by Kirby Bauer. Extended spectrum beta lactamase production (ESBL) was detected using combined disc method. Ciprofloxacin sensitivity was detected by nalidixic acid screening method. Minimum inhibitory concentration (MIC) of ciprofloxacin was determined by agar dilution method. Statistical analysis was …


A V3 Loop-Dependent Gp120 Element Disrupted By Cd4 Binding Stabilizes The Human Immunodeficiency Virus Envelope Glycoprotein Trimer, Shi-Hua Xiang, Andrés Finzi, Beatriz Pacheco, Kevin Alexander, Wen Yuan, Carlo Rizzuto, Chih-Chin Huang, Peter D. Kwong, Joseph Sodroski 2010 University of Nebraska-Lincoln

A V3 Loop-Dependent Gp120 Element Disrupted By Cd4 Binding Stabilizes The Human Immunodeficiency Virus Envelope Glycoprotein Trimer, Shi-Hua Xiang, Andrés Finzi, Beatriz Pacheco, Kevin Alexander, Wen Yuan, Carlo Rizzuto, Chih-Chin Huang, Peter D. Kwong, Joseph Sodroski

Virology Papers

Human immunodeficiency virus (HIV-1) entry into cells is mediated by a trimeric complex consisting of noncovalently associated gp120 (exterior) and gp41 (transmembrane) envelope glycoproteins. The binding of gp120 to receptors on the target cell alters the gp120-gp41 relationship and activates the membrane-fusing capacity of gp41. Interaction of gp120 with the primary receptor, CD4, results in the exposure of the gp120 third variable (V3) loop, which contributes to binding the CCR5 or CXCR4 chemokine receptors. We show here that insertions in the V3 stem or polar substitutions in a conserved hydrophobic patch near the V3 tip result in decreased gp120-gp41 association …


Role Of Geobacter Sulfurreducens Outer-Surface C-Type Cytochromes In Reduction Of Soil Humic Acid And Anthraquinone-2,6-Disulfonate, James W. Voordeckers, Byoung-Chan Kim, Mounir Izallalen, Derek Lovley 2010 University of Massachusetts - Amherst

Role Of Geobacter Sulfurreducens Outer-Surface C-Type Cytochromes In Reduction Of Soil Humic Acid And Anthraquinone-2,6-Disulfonate, James W. Voordeckers, Byoung-Chan Kim, Mounir Izallalen, Derek Lovley

Derek Lovley

Deleting individual genes for outer surface c-type cytochromes in Geobacter sulfurreducens partially inhibited the reduction of humic substances and anthraquinone-2,6,-disulfonate. Complete inhibition was obtained only when five of these genes were simultaneously deleted, suggesting that diverse outer surface cytochromes can contribute to the reduction of humic substances and other extracellular quinones.


Cd1d-Dependent B-Cell Help By Nk-Like T Cells Leads To Enhanced And Sustained Production Of Bacillus Anthracis Lethal Toxin-Neutralizing Antibodies, T. Scott Devera, Lindsay M. Aye, Gillian A. Lang, Sunil K. Joshi, Jimmy D. Ballard, Mark L. Lang 2010 Old Dominion University

Cd1d-Dependent B-Cell Help By Nk-Like T Cells Leads To Enhanced And Sustained Production Of Bacillus Anthracis Lethal Toxin-Neutralizing Antibodies, T. Scott Devera, Lindsay M. Aye, Gillian A. Lang, Sunil K. Joshi, Jimmy D. Ballard, Mark L. Lang

Bioelectrics Publications

The current Bacillus anthracis vaccine consists largely of protective antigen (PA), the protein of anthrax toxin that mediates entry of edema factor (EF) or lethal factor (LF) into cells. PA induces protective antibody (Ab)-mediated immunity against Bacillus anthracis but has limited efficacy and duration. We previously demonstrated that activation of CD1d-restricted natural killer-like T cells (NKT) with a CD1d-binding glycolipid led to enhanced Ab titers specific for foreign antigen (Ag). We therefore tested the hypothesis that activation of NKT cells with the CD1d ligand (alpha-galactosylceramide [alpha-GC]) at the time of immunization improves PA-specific Ab responses. We observed that alpha-GC enhanced …


Pichia Insulana Sp. Nov., A Novel Cactophilic Yeast From The Caribbean Free, Philip F. Ganter, Gianluigi Cardinali, Kyria Boundy-Mills 2010 Tennessee State University

Pichia Insulana Sp. Nov., A Novel Cactophilic Yeast From The Caribbean Free, Philip F. Ganter, Gianluigi Cardinali, Kyria Boundy-Mills

Biology Faculty Research

A novel species of ascomycetous yeast, Pichia insulana sp. nov., is described from necrotic tissue of columnar cacti on Caribbean islands. P. insulana is closely related to and phenotypically very similar to Pichia cactophila and Pichia pseudocactophila. There are few distinctions between these taxa besides spore type, host preference and locality. Sporogenous strains of P. insulana that produce asci with four hat-shaped spores have been found only on Curaçao, whereas there was no evidence of sporogenous P. cactophila from that island. In addition, sequences of the D1/D2 fragment of the large-subunit rDNA from 12 Curaçao strains showed consistent differences from …


Farnesol Signaling In Candida Albicans, Melanie L. Langford 2010 University of Nebraska at Lincoln

Farnesol Signaling In Candida Albicans, Melanie L. Langford

Dissertations and Theses in Biological Sciences

Candida albicans is a polymorphic fungus that causes a range of disease in humans, from mucosal infections to systemic disease. Its ability to cause disease is linked to conversion between yeast and filamentous forms of growth, and the first quorum-sensing molecule discovered in an eukaryote, farnesol, blocks this transition. In C. albicans, farnesol also kills mating-competent opaque cells, inhibits biofilm formation, protects the cells from oxidative stress, and can be a virulence factor or protective agent in disseminated and mucosal mouse models of infection, respectively. While much emphasis has been placed on determining its effect on C. albicans morphology, …


Effects Of Mold Exposure On Immune Cells, Katrin Gorham 2010 Bryant University

Effects Of Mold Exposure On Immune Cells, Katrin Gorham

Honors Projects in Science and Technology

The relationship between exposure to mold spores and human disease is only beginning to be understood. While evidence exists of strong correlations between moldy environments and allergic and infectious diseases, the relationship between exposure to specific species and human immune responses to them is not fully understood. This paper seeks to clarify this relationship by analyzing the effects of exposing murine immune cells to volatile organic compounds (VOCs) produced by different mold species. Mold species studied include Stachybotrys alternans; tests performed include cell viability studies and immunoassays. Results have implications for further research and treatment of mold-related diseases.


Role Of Flgt In Anchoring The Flagellum Of Vibrio Cholerae, Raquel M. Martinez, Brooke A. Jude, Thomas J. Kirn, Karen Skorupski, Ronald k. Taylor 2010 Dartmouth College

Role Of Flgt In Anchoring The Flagellum Of Vibrio Cholerae, Raquel M. Martinez, Brooke A. Jude, Thomas J. Kirn, Karen Skorupski, Ronald K. Taylor

Dartmouth Scholarship

Flagellar motility has long been regarded as an important virulence factor. In Vibrio cholerae, the single polar flagellum is essential for motility as well as for proper attachment and colonization. In this study, we demonstrate that the novel flagellar protein FlgT is involved in anchoring the flagellum to the V. cholerae cell. A screen for novel colonization factors by use of TnphoA mutagenesis identified flgT. An in-frame deletion of flgT established that FlgT is required for attachment, colonization, and motility. Transmission electron microscopy revealed that while the flgT mutant is capable of assembling a phenotypically normal flagellum, …


Section Abstracts: Biology With Microbiology And Molecular Biology, 2010 Old Dominion University

Section Abstracts: Biology With Microbiology And Molecular Biology

Virginia Journal of Science

Abstracts of the Biology with Microbiology and Molecular Biology Section for the 88th Annual Meeting for the Virginia Academy of Science, May 20-21, 2010, James Madison University, Harrisonburg, VA.


The Role Of Transcription In Stationary Phase Mutagenesis In Bacillus Subtilis, Holly Anne Martin 2010 University of Nevada Las Vegas

The Role Of Transcription In Stationary Phase Mutagenesis In Bacillus Subtilis, Holly Anne Martin

UNLV Theses, Dissertations, Professional Papers, and Capstones

Stationary phase mutagenesis, also known as stress-induced or adaptive mutagenesis, is defined as the accumulation of mutations during conditions of no net growth or conditions of stress. This process has been implicated in acquiring antibiotic resistance and evasion of host immune responses in microbial pathogens and in the generation of mutations that lead to neoplasia in animal cells. Previous work has shown that defects in DNA synthesis and repair systems contribute to the formation of adaptive mutations; however the role of transcription in the accumulation of mutations is still being examined. It is speculated that transcriptional derepression leads to an …


Cellular Immunity In Mouse Models Of Viral Encephalitis, Christina Dawn Steel 2010 Old Dominion University

Cellular Immunity In Mouse Models Of Viral Encephalitis, Christina Dawn Steel

Theses and Dissertations in Biomedical Sciences

Evidence is presented herein that intranasal application of vesicular stomatitis virus (VSV) caused acute infection of the murine central nervous system (CNS) with associated morbidity and significant mortality in mice. However, VSV encephalitis was not invariably fatal, suggesting that the CNS contained a professional antigen-presenting cell (APC) capable of inducing or propagating a protective antiviral immune response. To examine this possibility, we administered VSV via the intranasal route and then characterized the cellular elements that infiltrate the brain as well as the activation status of resident microglia, cells widely believed to represent the major APC population in the CNS. To …


An Assessment Of The Antioxidant And Antimicrobial Activity Of Six Species Of Edible Irish Seaweeds, Sabrina Cox, Nissreen Abu-Ghannam, Shilpi Gupta 2010 Technological University Dublin

An Assessment Of The Antioxidant And Antimicrobial Activity Of Six Species Of Edible Irish Seaweeds, Sabrina Cox, Nissreen Abu-Ghannam, Shilpi Gupta

Articles

Six species of edible Irish seaweeds; Laminaria digitata, Laminaria saccharina, Himanthalia elongata, Palmaria palmata, Chondrus crispus and Enteromorpha spirulina were screened for potential bioactivity. Extraction of secondary metabolites was carried out using different solvents to determine antioxidant and antimicrobial properties of the dried extracts. The total phenolic contents of dried methanolic extracts were significantly different (p < 0.05). H. elongata exhibited highest phenolic content at 151.3 mg GAE/g of seaweed extract and also had the highest DPPH scavenging activity (p < 0.05) with a 50% inhibition (EC50) level at 0.125μg/ml of extract. H. elongata also had the highest total tannin and total flavonoid contents (p < 0.05) of 38.34 mg CE/g and 42.5 mg QE/g, respectively. Antimicrobial activity was determined using a microtitre method which allowed detection of bacterial growth inhibition at low levels. All methanolic seaweed extracts inhibited the food spoilage and food pathogenic bacteria tested; Listeria monocytogenes, Salmonella abony, Enterococcus faecalis and Pseudomonas aeruginosa, except C. crispus extracts. It was found that dried methanolic extracts of red and green seaweeds had significantly lower antimicrobial activity than the brown species; H. elongata had the highest antimicrobial activity with up to 100% inhibition. In the studied work, the antimicrobial activity of red and green seaweed extracts significantly increased when ethanol and acetone were used as extraction solvents (p < 0.05). Inhibition of E. faecalis with C. crispus extracts increased from 39.28 to 100% when ethanol and acetone were applied as solvents.


Diversity Of Bacteria And Glycosyl Hydrolase Family 48 Genes In Cellulolytic Consortia Enriched From Thermophilic Biocompost, Javier A. Izquierdo, Maria V. Sizova, Lee R. Lynd 2010 Dartmouth College

Diversity Of Bacteria And Glycosyl Hydrolase Family 48 Genes In Cellulolytic Consortia Enriched From Thermophilic Biocompost, Javier A. Izquierdo, Maria V. Sizova, Lee R. Lynd

Dartmouth Scholarship

The enrichment from nature of novel microbial communities with high cellulolytic activity is useful in the identification of novel organisms and novel functions that enhance the fundamental understanding of microbial cellulose degradation. In this work we identify predominant organisms in three cellulolytic enrichment cultures with thermophilic compost as an inoculum. Community structure based on 16S rRNA gene clone libraries featured extensive representation of clostridia from cluster III, with one cluster sharing as little as 73% sequence similarity with the closest known relative. In all, 14 new GHF48 gene sequences were added to the known diversity of 35 genes from cultured …


Antimicrobial And Antioxidant Activities Of Essential Oil And Methanol Extract Of Jasminum Sambac From Djibouti, Fatou Abdoul-Latif, Prosper Edou, François Eba, Nabil Mohamed, Adwa Ali, Samatar Djama, Louis-Clément Obame, Mamoudou Hama DICKO 2010 University of Djibouti

Antimicrobial And Antioxidant Activities Of Essential Oil And Methanol Extract Of Jasminum Sambac From Djibouti, Fatou Abdoul-Latif, Prosper Edou, François Eba, Nabil Mohamed, Adwa Ali, Samatar Djama, Louis-Clément Obame, Mamoudou Hama Dicko

Pr. Mamoudou H. DICKO, PhD

The essential oil of jasminum sambac from Djibouti was subjected to screening for their possible antioxidant activity by two complementary test systems, namely DPPH free radical scavenging and beta-carotene-linoleic acid assays. Butylated hydroxytoluene (BHT) was used as positive control in both test systems. In the DPPH test system, the IC50 value of essential oil and methanol extract were respectively 7.43 and 2.30 μg/ml. In the beta-carotene-linoleic acid system, oxidation was effectively inhibited by Jasminum sambac, the RAA value of essential oil and methanol extract were respectively 96.6 and 93.9%. When compared to BHT, the essential oil and methanol extract had …


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