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Molecular Biology Of A Surface-Exposed Protein Family Of Bartonella Bacilliformis, Hannah Fay 2017 University of Montana

Molecular Biology Of A Surface-Exposed Protein Family Of Bartonella Bacilliformis, Hannah Fay

Undergraduate Theses and Professional Papers

Bartonella bacilliformis is a gram negative alpha-proteobacterium native to the Andes of South America. Bartonella causes Carrion’s disease, a potentially life threatening disease transmitted by the sand fly. It has a mortality rate of 88% when untreated and 10% when treated. Diagnostics and control measures for the disease are underdeveloped and no vaccine is available. Recent outbreaks indicate that the range of the pathogen is increasing with nearly 1.7 million people in western South America at risk. Little is known about the epidemiology and pathogenesis of B. bacilliformis. Recent research done by UC San Diego found a paralogous ...


Iron Acquisition Strategies Employed By Staphylococcus Lugdunensis, Jeremy R. Brozyna 2016 The University of Western Ontario

Iron Acquisition Strategies Employed By Staphylococcus Lugdunensis, Jeremy R. Brozyna

Electronic Thesis and Dissertation Repository

Iron is crucial for many cellular processes including DNA synthesis and respiration. The majority of iron in mammals is in heme within hemoproteins, inside cells, or transported through circulation by the glycoprotein transferrin, which constitutes the greatest iron source in serum. Limiting iron availability is an important facet of nutritional immunity to help prevent infection.

Staphylococcus lugdunensis is a human skin commensal and opportunistic pathogen capable of causing a variety of infections, including particularly aggressive endocarditis. It is an emerging pathogen with elevated virulence compared to other species of coagulase-negative staphylococci. The versatility of S. lugdunensis to infect multiple niches ...


Contribution Of A Putative Up Element Dna Sequence To The Activity Of A Newly Identified Phage Promoter, Courtney Hamilton 2016 Western Kentucky University

Contribution Of A Putative Up Element Dna Sequence To The Activity Of A Newly Identified Phage Promoter, Courtney Hamilton

Honors College Capstone Experience/Thesis Projects

In transcription, a universal step in gene expression, information from a DNA sequence is copied into RNA. A key component in gene expression is the promoter sequence, a region of DNA to which RNA polymerase binds during the initiation of transcription of downstream genes. Most bacterial promoters contain a -10 and a -35 sequence that are bound by the RNA polymerase. Some promoters also contain an Upstream Promoter (UP) element. UP elements have been shown to boost promoter activity. We recently identified a new promoter in a mutant bacteriophage that grows on a bacterial host that prevents antitermination of phage ...


Pseudomonas Fluorescens Hk44: Lessons Learned From A Model Whole-Cell Bioreporter With A Broad Application History, Josef Trögl, Archana Chauhan, Steven Ripp, Alice C. Layton, Gabriela Kuncová, Gary S. Sayler 2016 University of Tennessee, Knoxville

Pseudomonas Fluorescens Hk44: Lessons Learned From A Model Whole-Cell Bioreporter With A Broad Application History, Josef Trögl, Archana Chauhan, Steven Ripp, Alice C. Layton, Gabriela Kuncová, Gary S. Sayler

Steven Ripp

Initially described in 1990, Pseudomonas fluorescens HK44 served as the first whole-cell bioreporter genetically endowed with a bioluminescent (luxCDABE) phenotype directly linked to a catabolic (naphthalene degradative) pathway. HK44 was the first genetically engineered microorganism to be released in the field to monitor bioremediation potential. Subsequent to that release, strain HK44 had been introduced into other solids (soils, sands), liquid (water, wastewater), and volatile environments. In these matrices, it has functioned as one of the best characterized chemically-responsive environmental bioreporters and as a model organism for understanding bacterial colonization and transport, cell immobilization strategies, and the kinetics of cellular bioluminescent ...


Autonomous Bioluminescent Expression Of The Bacterial Luciferase Gene Cassette (Lux) In A Mammalian Cell Line, Dan M. Close, Stacey S. Patterson, Steven Ripp, Seung J. Baek, John Sanseverino, Gary S. Sayler 2016 University of Tennessee - Knoxville

Autonomous Bioluminescent Expression Of The Bacterial Luciferase Gene Cassette (Lux) In A Mammalian Cell Line, Dan M. Close, Stacey S. Patterson, Steven Ripp, Seung J. Baek, John Sanseverino, Gary S. Sayler

Steven Ripp

Background

The bacterial luciferase (lux) gene cassette consists of five genes (luxCDABE) whose protein products synergistically generate bioluminescent light signals exclusive of supplementary substrate additions or exogenous manipulations. Historically expressible only in prokaryotes, the lux operon was re-synthesized through a process of multi-bicistronic, codon-optimization to demonstrate for the first time self-directed bioluminescence emission in a mammalian HEK293 cell line in vitro and in vivo.

Methodology/Principal Findings

Autonomous in vitro light production was shown to be 12-fold greater than the observable background associated with untransfected control cells. The availability of reduced riboflavin phosphate (FMNH2) was identified as the limiting bioluminescence ...


Pseudomonas Fluorescens Hk44: Lessons Learned From A Model Whole-Cell Bioreporter With A Broad Application History, Josef Trögl, Archana Chauhan, Steven Ripp, Alice C. Layton, Gabriela Kuncová, Gary S. Sayler 2016 University of Tennessee, Knoxville

Pseudomonas Fluorescens Hk44: Lessons Learned From A Model Whole-Cell Bioreporter With A Broad Application History, Josef Trögl, Archana Chauhan, Steven Ripp, Alice C. Layton, Gabriela Kuncová, Gary S. Sayler

Steven Ripp

Initially described in 1990, Pseudomonas fluorescens HK44 served as the first whole-cell bioreporter genetically endowed with a bioluminescent (luxCDABE) phenotype directly linked to a catabolic (naphthalene degradative) pathway. HK44 was the first genetically engineered microorganism to be released in the field to monitor bioremediation potential. Subsequent to that release, strain HK44 had been introduced into other solids (soils, sands), liquid (water, wastewater), and volatile environments. In these matrices, it has functioned as one of the best characterized chemically-responsive environmental bioreporters and as a model organism for understanding bacterial colonization and transport, cell immobilization strategies, and the kinetics of cellular bioluminescent ...


Atp Luminescence Assay As A Bioburden Estimator Of Biomass Accumulation In Caves, Janez Mulec, Andreea Oarga-Mulec 2016 Karst Research Institute, Scientific Research Centre of the Slovenian Academy of Sciences and Arts

Atp Luminescence Assay As A Bioburden Estimator Of Biomass Accumulation In Caves, Janez Mulec, Andreea Oarga-Mulec

International Journal of Speleology

A commercially available adenosine triphosphate (ATP) detection system (Hygiena, USA), supported by cultivable microbial indicators, was used to estimate bioburden in different habitats in and outside show caves: air, water and solid surfaces. A strong positive correlation between ATP concentration expressed as Relative Light Units (RLU) and Colony-Forming-Units (CFU) was observed for swab samples from cave surfaces. In terms of ATP units, surfaces in a single cave system (Postojna Cave) varied considerably (240-1,258,800 RLU/ 20 cm2) and commonly exceeded the bioburden level of analogues on the surface (0-114,390 RLU/ 20 cm2). Cave sub-habitats were colonized ...


N-Methylation Of A Bactericidal Compound As A Resistance Mechanism In Mycobacterium Tuberculosis, Kenan C. Murphy, Carl F. Nathan 2016 University of Massachusetts Medical School

N-Methylation Of A Bactericidal Compound As A Resistance Mechanism In Mycobacterium Tuberculosis, Kenan C. Murphy, Carl F. Nathan

Open Access Articles

The rising incidence of antimicrobial resistance (AMR) makes it imperative to understand the underlying mechanisms. Mycobacterium tuberculosis (Mtb) is the single leading cause of death from a bacterial pathogen and estimated to be the leading cause of death from AMR. A pyrido-benzimidazole, 14, was reported to have potent bactericidal activity against Mtb. Here, we isolated multiple Mtb clones resistant to 14. Each had mutations in the putative DNA-binding and dimerization domains of rv2887, a gene encoding a transcriptional repressor of the MarR family. The mutations in Rv2887 led to markedly increased expression of rv0560c. We characterized Rv0560c as an S-adenosyl-L-methionine-dependent ...


Relationship Between Morphogenesis And Secretion In The Filamentous Fungus Aspergillus Nidulans, Lakshmi Preethi Yerra 2016 University of Nebraska-Lincoln

Relationship Between Morphogenesis And Secretion In The Filamentous Fungus Aspergillus Nidulans, Lakshmi Preethi Yerra

Dissertations and Theses in Biological Sciences

Filamentous fungi have a long history in biotechnology for the production of food ingredients, pharmaceuticals and enzymes. The advancements made in recent years have earned filamentous fungi such as Aspergillus species a dominant place among microbial cell factories. Although the model fungus A. nidulans has been extensively studied, the genetic and regulatory networks that underlie morphogenesis and development have yet to be fully characterized. The Rho GTPases (Cdc42 and RacA) are one of the most important regulators of the morphogenetic processes among diverse eukaryotic organisms. Although the functions of these GTPases are relatively well-characterized, little is known about their downstream ...


Characterization Of The Role Of Host And Dietary Factors In The Establishment Of Bacteria In The Gastrointestinal Tract, Janina A. Krumbeck 2016 University of Nebraska - Lincoln

Characterization Of The Role Of Host And Dietary Factors In The Establishment Of Bacteria In The Gastrointestinal Tract, Janina A. Krumbeck

Dissertations and Theses in Biological Sciences

Probiotic bacteria and synbiotics are used as therapeutic and prophylactic agents. The majority of probiotic and synbiotic applications contain bacterial strains that are allochthonous to the human gastrointestinal (GI) tract. Accordingly, many bacterial strains do not survive digestion, or are not capable of persisting and competing the resident gut microbiota, and are therefore washed out of the GI tract shortly after the treatment is discontinued. This might reduce the health effects of these treatments. Therefore, research is needed to address the ecological challenges that probiotic strains encounter in the GI tract in order to develop probiotic regimens. Determining which ecological ...


Do Novel Weapons That Degrade Mycorrhizal Mutualisms Explain Invasive Species Success?, Philip L. Pinzone Mr. 2016 Buffalo State College

Do Novel Weapons That Degrade Mycorrhizal Mutualisms Explain Invasive Species Success?, Philip L. Pinzone Mr.

Biology Theses

Invasive plants often dominate novel habitats where they did not co-evolve with local species. Several hypotheses suggest mechanisms that explain increased exotic plant success, including 'novel weapons' and 'degraded mutualisms'. Japanese knotweed (Fallopia japonica) and European buckthorn (Rhamnus cathartica) are widespread plant invaders in North America that can dominate ecosystems. The goal of this study is to test whether these impacts are more consistent with novel weapons or degraded mutualism hypotheses. I examine tree seedling recruitment, (germination and initial survival) growth, (biomass) and mycorrhizal invasion (AMF content) as a function of F. japonica and R. cathartica root exudates. Given that ...


Retention Of Mothers And Infants In The Prevention Of Mother-To-Child Transmission Of Hiv Programme Is Associated With Individual And Facility-Level Factors In Rwanda., Godfrey B Woelk, Dieudonne Ndatimana, Sally Behan, Martha Mukaminega, Epiphanie Nyirabahizi, Heather J. Hoffman, Placidie Mugwaneza, Muhayimpundu Ribakare, Anouk Amzel, B Ryan Phelps 2016 George Washington University

Retention Of Mothers And Infants In The Prevention Of Mother-To-Child Transmission Of Hiv Programme Is Associated With Individual And Facility-Level Factors In Rwanda., Godfrey B Woelk, Dieudonne Ndatimana, Sally Behan, Martha Mukaminega, Epiphanie Nyirabahizi, Heather J. Hoffman, Placidie Mugwaneza, Muhayimpundu Ribakare, Anouk Amzel, B Ryan Phelps

Epidemiology and Biostatistics Faculty Publications

OBJECTIVES: Investigate levels of retention at specified time periods along the prevention of mother-to-child transmission (PMTCT) cascade among mother-infant pairs as well as individual- and facility-level factors associated with retention.

METHODS: A retrospective cohort of HIV-positive pregnant women and their infants attending five health centres from November 2010 to February 2012 in the Option B programme in Rwanda was established. Data were collected from several health registers and patient follow-up files. Additionally, informant interviews were conducted to ascertain health facility characteristics. Generalized estimating equation methods and modelling were utilized to estimate the number of mothers attending each antenatal care visit ...


Dietary Weight Loss Advice In Us Health Magazines And Its Relation To Ancestral Diet, Risa J. Stein, Marium A. Choudhry, Thomas J. Murray Jr. 2016 Rockhurst University

Dietary Weight Loss Advice In Us Health Magazines And Its Relation To Ancestral Diet, Risa J. Stein, Marium A. Choudhry, Thomas J. Murray Jr.

Journal of Evolution and Health

As rates of overweight and obesity have risen in the US, the public has sought effective strategies for weight loss through dietary modification. A proliferation of processed foods and changing governmental nutrition guidelines have both impacted dietary intake patterns. While physicians are considered respectable sources of weight-loss information, increasingly the public has turned to the media, particularly magazines, for weight loss advice. This study investigated the dietary recommendations found in the five leading US health-related magazines and compared those recommendations to ancestral diets. With a couple notable exceptions, leading health magazines present consistent recommendations for dietary modifications to promote weight ...


Closing The Net On Retroviruses, Jeremy Luban 2016 University of Massachusetts Medical School

Closing The Net On Retroviruses, Jeremy Luban

Open Access Articles

Structural studies reveal how an antiviral factor forms a molecular net to restrict retroviruses including HIV-1.


Separate F-Type Plasmids Have Shaped The Evolution Of The H30 Subclone Of Escherichia Coli Sequence Type 131., Timothy J Johnson, Jessica L Danzeisen, Bonnie Youmans, Kyle Case, Katharine Llop, Jeannette Munoz-Aguayo, Cristian Flores-Figueroa, Maliha Aziz, Nicole Stoesser, Evgeni Sokurenko, Lance B. Price, James R Johnson 2016 George Washington University

Separate F-Type Plasmids Have Shaped The Evolution Of The H30 Subclone Of Escherichia Coli Sequence Type 131., Timothy J Johnson, Jessica L Danzeisen, Bonnie Youmans, Kyle Case, Katharine Llop, Jeannette Munoz-Aguayo, Cristian Flores-Figueroa, Maliha Aziz, Nicole Stoesser, Evgeni Sokurenko, Lance B. Price, James R Johnson

Environmental and Occupational Health Faculty Publications

The extraintestinal pathogenic Escherichia coli (ExPEC) H30 subclone of sequence type 131 (ST131-H30) has emerged abruptly as a dominant lineage of ExPEC responsible for human disease. The ST131-H30 lineage has been well described phylogenetically, yet its plasmid complement is not fully understood. Here, single-molecule, real-time sequencing was used to generate the complete plasmid sequences of ST131-H30 isolates and those belonging to other ST131 clades. Comparative analyses revealed separate F-type plasmids that have shaped the evolution of the main fluoroquinolone-resistant ST131-H30 clades. Specifically, an F1:A2:B20 plasmid is strongly associated with ...


Comparative Genomics, Transcriptomics, And Physiology Distinguish Symbiotic From Free-Living Chlorella Strains, Cristian F. Quispe, Olivia Sonderman, Maya Khasin, Wayne R. Riekhof, James Van Etten, Kenneth Nickerson 2016 University of Nebraska-Lincoln

Comparative Genomics, Transcriptomics, And Physiology Distinguish Symbiotic From Free-Living Chlorella Strains, Cristian F. Quispe, Olivia Sonderman, Maya Khasin, Wayne R. Riekhof, James Van Etten, Kenneth Nickerson

Kenneth Nickerson Papers

Most animal–microbe symbiotic interactions must be advantageous to the host and provide nutritional benefits to the endosymbiont. When the host provides nutrients, it can gain the capacity to control the interaction, promote self-growth, and increase its fitness. Chlorella-like green algae engage in symbiotic relationships with certain protozoans, a partnership that significantly impacts the physiology of both organisms. Consequently, it is often challenging to grow axenic Chlorella cultures after isolation from the host because they are nutrient fastidious and often susceptible to virus infection. We hypothesize that the establishment of a symbiotic relationship resulted in natural selection for nutritional and ...


Sequencing And Comparative Analysis Of De Novo Genome Assemblies Of Streptomyces Aureofaciens Atcc 10762, Julien S. Gradnigo 2016 University of Nebraska - Lincoln

Sequencing And Comparative Analysis Of De Novo Genome Assemblies Of Streptomyces Aureofaciens Atcc 10762, Julien S. Gradnigo

Dissertations and Theses in Biological Sciences

Streptomyces aureofaciens is a Gram-positive Actinomycete used for commercial antibiotic production. Although it has been the subject of many biochemical studies, no public genome resource was available prior to this project. To address this need, the genome of S. aureofaciens ATCC 10762 was sequenced using a combination of sequencing platforms (Illumina and 454-shotgun). Multiple de novo assembly methods (SGA, IDBA, Trinity, SOAPdenovo2, MIRA, Velvet and SPAdes) as well as combinations of these methods were assessed to determine which provided the most robust assembly. Combination strategies led to a consistent overestimation of the total genome size. Empirical data from targeted PCR ...


From Milpas To The Market: A Study On The Use Of Metal Silos For Safer And Better Storage Of Guatemalan Maize, José Rodrigo Mendoza 2016 University of Nebraska-Lincoln

From Milpas To The Market: A Study On The Use Of Metal Silos For Safer And Better Storage Of Guatemalan Maize, José Rodrigo Mendoza

Dissertations & Theses in Food Science and Technology

This project aimed to implement the use of metal silos to improve quality and safety of maize consumed by inhabitants of the highlands of Guatemala. This manuscript includes a literature review of the maize production chain in Guatemala, a survey about agricultural practices used in the region of study, as well as a characterization of the analyzed maize regarding its mycoflora, nutritional composition, and insect infestation. To better understand the current situation regarding agricultural practices and maize consumption, a survey was carried out. Sample consisted of 280 families representing 14 rural communities distributed in the townships of Todos Santos and ...


Effects Of Piscine Reovirus Infection On Innate Immune Signalling In Salmon, Mark Polinski 2016 Fisheries and Oceans Canada

Effects Of Piscine Reovirus Infection On Innate Immune Signalling In Salmon, Mark Polinski

2nd International Conference of Fish & Shellfish Immunology

No abstract provided.


Inhibition Of Lentivirus Replication By Aqueous Extracts Of Prunella Vulgaris, Melinda A. Brindley, Mark P. Widrlechner, Joe-Ann McCoy, Patricia A. Murphy, Catherine C. Hauck, Ludmila Rizshsky, Basil J. Nikolau, Wendy Maury 2016 University of Iowa

Inhibition Of Lentivirus Replication By Aqueous Extracts Of Prunella Vulgaris, Melinda A. Brindley, Mark P. Widrlechner, Joe-Ann Mccoy, Patricia A. Murphy, Catherine C. Hauck, Ludmila Rizshsky, Basil J. Nikolau, Wendy Maury

Basil Nikolau

Background
Various members of the mint family have been used historically in Chinese and Native American medicine. Many of these same family members, including Prunella vulgaris, have been reported to have anti-viral activities. To further characterize the anti-lentiviral activities of P. vulgaris, water and ethanol extractions were tested for their ability to inhibit equine infectious anemia virus (EIAV) replication.

Results
Aqueous extracts contained more anti-viral activity than did ethanol extracts, displaying potent anti-lentiviral activity against virus in cell lines as well as in primary cell cultures with little to no cellular cytotoxicity. Time-of-addition studies demonstrated that the extracts were effective ...


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