Purification And Characterization Of Bcsc; An Integral Component Of Bacterial Cellulose Export,
2015
Wilfrid Laurier University
Purification And Characterization Of Bcsc; An Integral Component Of Bacterial Cellulose Export, Emily D. Wilson Ms
Theses and Dissertations (Comprehensive)
Biofilms are a growing concern in the medical field due to their increased resistance to antibiotics. When found in a biofilm, bacteria can have antibiotic resistance 10-1000 times that of their planktonic counterparts. Therefore, it is important to study the formation of biofilms. Cellulose biofilms are formed by Enterobacteriaceae, such as many Escherichia coli and Salmonella spp. strains. Biofilms provide these species with benefits including antimicrobial protection, development of bacterial communities, promotion of DNA exchange, uptake of nutrients, and, in the case of cellulose biofilms, immune system evasion. Cellulose biofilms are controlled by the Bacterial cellulose synthesis (Bcs) complex located …
Characterization Of A Biosynthetic Pathway Yielding Anticancer Natural Products From A Marine Bacterium,
2015
University of North Florida
Characterization Of A Biosynthetic Pathway Yielding Anticancer Natural Products From A Marine Bacterium, Elle D. James
UNF Graduate Theses and Dissertations
Natural products are bioactive secondary metabolites produced by living organisms and are prevalently utilized as pharmaceutical drugs. Marine adapted organisms are a promising source of new natural products possessing unique chemical structures and biological activities. By studying the biosynthetic pathways employed by living organisms to produce natural products, insights into new strategies to generate molecules to combat disease and overcome drug resistance may be gained. This thesis study aimed to uncover the biosynthetic pathway employed by a marine actinomycete, Nocardiopsis sp. CMB-M0232, to catalyze the assembly of the nocardioazines. These molecules are a group of 2,5-diketopiperazine natural products that feature …
Characterization Of Salmonella Enterica Isolates From Food And Clinical Samples: Functionality Of Cytolethal Distending Toxin (Cdt) From Non-Typhi Salmonella Enterica,
2014
University of Arkansas Little Rock
Characterization Of Salmonella Enterica Isolates From Food And Clinical Samples: Functionality Of Cytolethal Distending Toxin (Cdt) From Non-Typhi Salmonella Enterica, Ezat Hussain Mezal
Theses and Dissertations
Salmonella enterica is recognized worldwide as a significant cause of both human and animal disease. Recently, many random outbreaks of infections associated with the pathogens have been documented. Thus, state of the art molecular tools are necessary to conduct effective surveillance that would aid monitoring and prevention of disease. In this study, 110 Salmonella enterica serovars (Enteritidis & Javiana) strains isolated from food, environmental and clinical samples were analyzed for genetic diversity, antibiotic resistance, presence of virulence genes, plasmids, and plasmid replicon types. To assess the genetic diversity, pulsed-field gel electrophoresis (PFGE) fingerprinting, multiple-locus variable-number tandem repeat analysis (MLVA) and …
In The Social Amoeba, Dictyostelium Discoideum , Density, Not Farming Status, Determines Predatory Success On Unpalatable Escherichia Coli,
2014
Washington University in St Louis
In The Social Amoeba, Dictyostelium Discoideum , Density, Not Farming Status, Determines Predatory Success On Unpalatable Escherichia Coli, Susanne Disalvo, Debra A. Brock, Jeff Smith, David C. Queller, Joan E. Strassmann
Biology Faculty Research
Background
The social amoeba Dictyostelium discoideum interacts with bacteria in a variety of ways. It is a predator of bacteria, can be infected or harmed by bacteria, and can form symbiotic associations with bacteria. Some clones of D. discoideum function as primitive farmers because they carry bacteria through the normally sterile D. discoideum social stage, then release them after dispersal so the bacteria can proliferate and be harvested. Some farmer-associated bacteria produce small molecules that promote host farmer growth but inhibit the growth of non-farmer competitors. To test whether the farmers’ tolerance is specific or extends to other growth inhibitory …
Draft Genome Sequence Of New Bacillus Cereus Strain Tsu1,
2014
Tennessee State University
Draft Genome Sequence Of New Bacillus Cereus Strain Tsu1, Hui Li, Suping Zhou, Terrance Johnson, Koen Vercruysse, Alexander J. Ropelewski, Theodore W. Thannhauser
Agricultural and Environmental Sciences Faculty Research
This paper reports the draft genome sequence of new Bacillus cereus strain tsu1, isolated on an agar-cellulose plate. The draft genome sequence is 5.81 Mb, revealing 5,673 coding sequences. It contains genes for cellulose-degradation and biosynthesis pathways of polyhydroxybutyrate (PHB) and 8 rRNA genes (5S, 16S, and 23S).
Colloidal And Biological Properties Of Triscationic Amphiphiles With One Or Two Tails,
2014
James Madison University
Colloidal And Biological Properties Of Triscationic Amphiphiles With One Or Two Tails, John N. Marafino
Masters Theses, 2010-2019
The decline in the development of novel antimicrobials, combined with the misusage and over prescription of antibiotics, has contributed to the increasing prevalence of antimicrobial-resistant infections. Thus development of effective novel disinfectants could reduce the transmission of pathogens and decrease the risk of infection by antibiotic resistant organisms. The antimicrobial activity of amphiphiles, compounds with hydrophobic and hydrophilic regions, was first reported in 1935, and has influenced the synthesis of amphiphiles with variations in structure. In this study, three series of amphiphiles were synthesized by two subsequent Menshutkin reactions. Each amphiphile contains one or two hydrocarbon tails ranging from 8 …
Characterization Of Vibrio Vulnificus Strains Using Phenotypic And Genotypic Assays,
2014
James Madison University
Characterization Of Vibrio Vulnificus Strains Using Phenotypic And Genotypic Assays, James Conrad
Masters Theses, 2010-2019
In this study 143 V. vulnificus isolates of clinical and environmental origin, were examined for growth on differential media, identified to species and tested for antibiotic resistance. A multiplex PCR was created and optimized, and phylogenetic analysis was conducted. The first objective was to compare phenotypic methods to identify V. vulnificus. Colony colors of confirmed V. vulnificus isolates on selective media (Vibrio vulnificus agar, thiosulfate citrate bilesalts sucrose agar, CHROMAgar Vibrio (CAV), and colistin polymyxin B cellobiose agar), mostly matched those characteristic of V. vulnificus. To test the ability of these media to select for V. vulnificus, new presumptive V. …
Microbial Community Shifts Caused By Changes In The Primary Oxidant At A Drinking Water Treatment Plant,
2014
University of Arkansas, Fayetteville
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 Phenotypic Effects And Transcript Response Of Salt Stress, The Impact Of Viral Infection On Salt Stress Symptoms, And The Effect Of Salt Stress On Soybean Virus Vector Activity In Soybean Varieties That Vary In Chloride Uptake,
2014
University of Arkansas, Fayetteville
The Phenotypic Effects And Transcript Response Of Salt Stress, The Impact Of Viral Infection On Salt Stress Symptoms, And The Effect Of Salt Stress On Soybean Virus Vector Activity In Soybean Varieties That Vary In Chloride Uptake, Alma Glenn Laney
Graduate Theses and Dissertations
With the increase in saline soils worldwide, understanding the mechanisms for salt tolerance in plants is important to reduce yield loss due to salt stress. Soybean, Glycine max (L.) Merr., genotypes differ in chloride uptake with genotypes that take up chloride into foliar tissues tending to be salt-sensitive whereas those that partially exclude chloride from the leaves are more salt-tolerant. Transcriptional and physiological responses were measured in two soybean cultivars, Clark and Manokin, which differ in chloride uptake in response to salt stress and in combination with Soybean mosaic virus (SMV) and its aphid vector, Aphis glycines . The interaction …
Melatonin And Neurogenesis: A Comparative Study Of The Efficacy Of Melatonin, Its Precursors, And L-Dopa On Neural Stem Cell Metabolism In Human Adult Neurospheres,
2014
University of Central Florida
Melatonin And Neurogenesis: A Comparative Study Of The Efficacy Of Melatonin, Its Precursors, And L-Dopa On Neural Stem Cell Metabolism In Human Adult Neurospheres, Omar Heriba
HIM 1990-2015
Human neurosphere stem cells offer promising potential for the treatment of neurodegenerative diseases. Their well characterized multi-potency of differentiating into neurons, astrocytes, and oligodendrocytes when exposed to the optimum exogenous growth factors make them an exciting area of study (38). Finding novel endogenous methods of modulating stem cell metabolism will allow for the safer treatment of various brain disorders (34). In this experiment, melatonin, N-acetylserotonin, L-tryptophan, and L-DOPA are added in three different concentrations to neurospheres suspended in HNSC/GBM media with less than optimal concentrations of exogenous epidermal growth factor (EGF) and fibroblast growth factor (FGF). The alamarBlue assay (resazurin) …
Characterization And Role Of Msaabcr In Biofilm Development And Virulence In Staphylococcus Aureus,
2014
University of Southern Mississippi
Characterization And Role Of Msaabcr In Biofilm Development And Virulence In Staphylococcus Aureus, Gyan Sundar Sahukhal
Dissertations
Community-acquired, methicillin-resistant Staphylococcus aureus strains often cause localized infections in immune-compromised hosts, but some strains show enhanced virulence leading to severe infections even among healthy individuals with no predisposing risk factors. The genetic basis for this enhanced virulence has yet to be determined. S. aureus possesses a wide variety of virulence factors, the expression of which is carefully coordinated by a variety of regulators. Several virulence regulators have been well characterized, but others have yet to be thoroughly investigated. Previously, the msa gene as a regulator of several virulence genes, biofilm development, and antibiotic …
Characterization Of Biofilms On Medical Device Materials With Application To Reusable Surgical Instruments,
2014
Clemson University
Characterization Of Biofilms On Medical Device Materials With Application To Reusable Surgical Instruments, Amanda Macaluso
All Theses
Reusable medical devices or reprocessed single-use devices are original medical devices that have been used once and then are cleaned, sterilized, and remanufactured for the purpose of an additional single use on a single patient [4]. Improperly reprocessed devices are a significant contributor to hospital-associated infections [4]. Challenges that hinder reprocessing are related to the complexity of reusable medical device design, the necessary validation of cleaning protocols required by the U.S Food and Drug Administration (FDA), the impact of human factors throughout the reprocessing cycle, as well as economic factors within new business models that are centered on reprocessing. Current …
Enhancement Of Antimicrobial Activity Of Naturally Occuring Phenolic Compounds By Nano-Particle Mediated Delivery Against Listeria Monocytogenes, Escherichia Coli O157:H7, And Salmonella Typhimurium,
2014
University of Arkansas, Fayetteville
Enhancement Of Antimicrobial Activity Of Naturally Occuring Phenolic Compounds By Nano-Particle Mediated Delivery Against Listeria Monocytogenes, Escherichia Coli O157:H7, And Salmonella Typhimurium, Madhuram Ravichandran
Graduate Theses and Dissertations
Food-borne illnesses are of major concern in the U.S. and worldwide. Salmonella,Listeria,E. coli O157:H7 continue to be some of the major foodborne pathogens. Recurring recalls due to these pathogens demand critical antimicrobial strategies to decontaminate the food through its procession from farm to fork. In our study, we combined the effectiveness of naturally occurring phenolic compounds individually, with/ without ethylenediamine tetraacetic acid (EDTA) and/or Nisin and nanoparticle delivery to improve the antimicrobial potential of the compounds against Listeria monocytogenes (L.m.), Salmonella Typhimurium (S.T.), and Escherichia coli O157:H7 (E.c.), in brain …
Using The Yeast Two-Hybrid System To Determine The Function Of Parkin E3 Ubiquitin Ligase,
2014
University of Central Florida
Using The Yeast Two-Hybrid System To Determine The Function Of Parkin E3 Ubiquitin Ligase, Vanessa Nguyen
HIM 1990-2015
Parkin is a cytosolic E3 ubiquitin ligase that is recruited to the mitochondria during cellular stress and has been suggested to be involved in a variety of biological processes such as mitophagy. The recruitment of Parkin (PARK2) to the mitochondria is dependent upon the kinase activity and the accumulation of PINK1 on damaged mitochondria. Mutations in either PINK1 or Parkin genes disrupt this protective pathway and lead to the accumulation of damaged mitochondria. From a clinical standpoint, mutations in the PARK2 gene have been associated with the progression and onset of autosomal recessive juvenile parkinsonism. Without the presence of a …
Effects Of Water Column P-Availability And Litter Microbial Mediated Processes And Stoichiometry In Aquatic Systems,
2014
University of Arkansas, Fayetteville
Effects Of Water Column P-Availability And Litter Microbial Mediated Processes And Stoichiometry In Aquatic Systems, Ayla Smartt
Graduate Theses and Dissertations
Anthropogenic nutrient enrichment of aquatic ecosystems is prevalent and can have detrimental effects on biological condition. Many of these effects have been attributed directly or indirectly to changes in autotrophic processes. However, in detrital-based streams changes in course detrital stoichiometry and decomposition have been related to changes community structure and production at higher trophic levels highlighting the importance of considering the heterotrophic microbial responses to enrichment. Leaf litter stoichiometry, which is determined in part by the tree species source and the microbial communities that comprise the associated biofilm, is likely related to decomposition rates, but few studies examine these variables …
Spring Thaw Ionic Pulses Boost Nutrient Availability And Microbial Growth In Entombed Antarctic Dry Valley Cryoconite Holes,
2014
University of Bristol
Spring Thaw Ionic Pulses Boost Nutrient Availability And Microbial Growth In Entombed Antarctic Dry Valley Cryoconite Holes, Jon Telling, Alexandre M. Anesio, Martyn Tranter, Andrew G. Fountain, Thomas H. Nylen, Jon Hawkings, Virendra B. Singh, Preeti Kaur, Michaela Musilova, Jemma L. Wadham
Geology Faculty Publications and Presentations
The seasonal melting of ice entombed cryoconite holes on McMurdo Dry Valley glaciers provides oases for life in the harsh environmental conditions of the polar desert where surface air temperatures only occasionally exceed 0°C during the Austral summer. Here we follow temporal changes in cryoconite hole biogeochemistry on Canada Glacier from fully frozen conditions through the initial stages of spring thaw toward fully melted holes. The cryoconite holes had a mean isolation age from the glacial drainage system of 3.4 years, with an increasing mass of aqueous nutrients (dissolved organic carbon, total nitrogen, total phosphorus) with longer isolation age. During …
Modulation Of The Ovarian Cancer Humoral Response By Tumor-Derived Exosomes.,
2014
University of Louisville
Modulation Of The Ovarian Cancer Humoral Response By Tumor-Derived Exosomes., Carolyn Denise Roberson
Electronic Theses and Dissertations
The pathogenesis of epithelial ovarian cancer is complicated by its diagnosis during the latter stages of the disease resulting from lack of symptoms or from presence of symptoms that mimic other conditions. Because of the often fatal prognosis by the time of actual detection, efforts are being made to better understand the host immune response to ovarian cancer. In this study, the contributions of the humoral immune response were investigated by focusing on the role of tumor-derived exosomes and their ability to modulate humoral immune responses. First, ovarian cancer patient-derived free circulating antibodies were investigated for immunoreactivity to patient antigen. …
The Use Of Surface Cytokines As Biomarkers In B Cell Mediated Autoimmune Diseases,
2014
Loma Linda University
The Use Of Surface Cytokines As Biomarkers In B Cell Mediated Autoimmune Diseases, Abby Jones Weldon
Loma Linda University Electronic Theses, Dissertations & Projects
RA and SLE are B cell-mediated autoimmune diseases dominated by autoantibodies that affect over 1.5 million Americans. Together RA and SLE contribute to over 29 billion in healthcare costs, therefore due to the high financial burden and physical toll of these diseases on the population, there is a critical need to effectively and efficiently diagnose and treat RA and SLE patients. The aim of our studies was to identify biomarkers and drug targets to improve the identification and treatment of RA and SLE patients. As discussed above, APRIL, BAFF and TSLP have been implicated in the pathogenesis of RA and …
A Portable Impedance Biosensing System Based On A Laptop With Labview For Rapid Detection Of Avian Influenza Virus,
2014
University of Arkansas, Fayetteville
A Portable Impedance Biosensing System Based On A Laptop With Labview For Rapid Detection Of Avian Influenza Virus, Yixiang Wang
Graduate Theses and Dissertations
Avian Influenza Virus (AIV) H5N1 is a highly pathogenic virus found not only in birds but also in human. Rapid and sensitive detection method is needed to help prevent the spread of AIV H5N1. In this study, a portable impedance biosensing system based on a laptop with LabVIEW software was developed for detection of AIV H5N1. First, a virtual instrument was programmed with LabVIEW software to form a platform for impedance measurement, data processing and control. The audio card of a laptop was used as a function generator while a data acquisition card was used with the signal channels for …
Enhancing Protein And Enzyme Stability Through Rationally Engineered Site-Specific Immobilization Utilizing Non-Canonical Amino Acids,
2014
Brigham Young University - Provo
Enhancing Protein And Enzyme Stability Through Rationally Engineered Site-Specific Immobilization Utilizing Non-Canonical Amino Acids, Jeffrey Chun Wu
Theses and Dissertations
The demand for economical, efficient protein production, reuse, and recovery has never been greater due to their versatility in a large variety of applications ranging from industrial chemical manufacturing to pharmaceutical drug production. The applications for naturally and artificially produced proteins include protein drugs and other pharmaceutical products, as biocatalysts in environmentally friendly chemical manufacturing, as enzymes for food processing purposes, and as an essential component in many biomedical devices. However, protein production suffers from many challenges, which include the cost of production, protein stability especially under harsh conditions, and recoverability and reusability of the proteins. The combination of two …
