Bacteriology Commons^™

Host Pathogen Interactions: Is Arabidopsis Thaliana Remembered By Its Nemesis Pseudomonas Syringae?, Daniel Z. Kreiser

Lawrence University Honors Projects

Plants contain innate immune systems that deter pathogen infection. Pattern recognition receptors bind microbe-associated molecular patterns (MAMPs), triggering immunity. MAMPs are proteins exclusive to pathogens that are typically indispensable for their survival. For this reason, MAMPs cannot be mutated or removed without causing pathogen death. However, this does not necessitate constitutive expression of MAMPs. In this study, the MAMP response of Arabidopsis thaliana was utilized to determine differential detection of MAMPs expressed by Pseudomonas syringe pv. tomato DC3000 when pretreated with A. thaliana. Results demonstrated that more MAMPs are detected when P. syringae had previously encountered A. thaliana, …

Cloning And Characterization Of The Cell Wall Acting Enzyme Cd1034 From The Pathogen Clostridium Difficile, Zachary Suter

Honors Projects in Science and Technology

The manifestation of multidrug resistance in bacteria over the past several decades has resulted in one of the foremost challenges in the management of infectious diseases. The question arises, “How do we address this growing problem?” One solution to stem the growing rise in antimicrobial resistance is to investigate new targets, while another approach is to re-examine classical antibacterial targets with a fresh perspective. The aim of this paper is to begin the process of antibacterial development for the pathogen Clostridium difficile by characterizing the cell wall acting glucosaminidase CD1034. It is inunderstanding how CD1034 functions biochemically that it can …

Performance Screening Of Chemostat Adapted Recombinant Zymomonas Mobilis Strains, Deirdre M. Beard, Nancy Dowe

STAR Program Research Presentations

Corn stover biomass can be pretreaed and hydrolyzed into soluble sugars to be fermented by microorganisms to ethanol. NREL has developed a recombinant bacteria Zymomonas mobilis 8b that metabolizes both five and six carbon sugars. During pretreatment, toxic inhibitors such as furfural and acetate are produced. NREL has made an attempt to adapt two sub-strains of Z. mobilis 8b to acetate and furfural by using a chemostat method. During the chemostat process, cultures were frozen back in glycerol and saved. In this study, those frozen cultures were revived and analyzed for performance in environments with varying concentrations of furfural and …

Adding Upstream Sequence And A Downstream Reporter To The Bile Acid Inducible Promoter Of Clostridium Scindens Vpi 12708, Bryan Patrick Mason

Masters Theses & Specialist Projects

Bile acids in the small intestines of animals serve to breakdown fats and fatsoluble vitamins. Most of the bile acids are reabsorbed into the enterohepatic circulation, but approximately five percent of these bile acids pass into the large intestine. These bile acids are swiftly deconjugated by the bacterial population, and then subjected to further intestinal bacterial chemical modifications. The most significant of these modifications are 7α-dehydroxylations which form secondary bile acids (deoxycholate and lithocholate). Much research has illuminated the 7α-dehydroxylation pathway: of particular interest is the bile acid inducible operon, for which Clostridium scindens VPI 12708 serves as the model …

Protection Of Macrophages J774a.1 By Purine Nucleoside Analogues From Bacillus Anthracis Mediated Necrosis, Zadkiel R. Alvarez

UNLV Theses, Dissertations, Professional Papers, and Capstones

Eight years after the lamentable anthrax attacks, major scientific effort continues to be done, in order to stop imminent acts of bioterrorism. Innovative ways of therapy against the anthrax disease are being investigated. B. anthracis, the etiological agent of the infection, has a dormant stage in its life cycle known as the endospore. When conditions become favorable spores germinate, transforming into vegetative bacteria. In inhalational anthrax, the most fatal manifestation of the disease, spores enter the organism through the respiratory track, and are phagocytosized by alveolar macrophages of the lungs. Spores are able to sense nutrient availability, activating their germination …

Development And Characterization Of Eukaryotic Biomimetic Liposomes, Bradley Jay Taylor

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study developed and characterized phospholipid vesicles, or liposomes, that mimic cell surfaces. Microemulsified liposomes contained biotinylated phosphatidylethanolamine, allowing them to be immobilized to avidin-coated glass. Laminin (LN), glycosphingolipids (GMl and GM3), and Escherichia coli's mechanosensitive channel of large conductance (EcoMscL) were embedded into liposome membranes. It was determined whether these embedded molecules exhibited their physiological roles of adhesion, cell recognition, and mechanosensation, respectively. Confocal laser scanning microscopy (CLSM) was employed to examine the interaction of fluorescently probed proteins, toxins, and bacteria with the immobilized microemulsified liposomes. Capture of individual and simultaneous multiple species of bacteria by GMl, GM3, …

Comparison Of Tnf-A Levels Produced By Macrophages Treated With Brucella Abortus And Escherichia Coli Lps, Tajie Harris

Honors Capstones

Capstone submitted as a graduation requirement for the BSU Honors Program.

Studies On Muropeptide Amino Acids Of Rhizobium Japonicum, Mohammed Alauddin

Masters Theses

The isolation of Rhizobium japonicum cell walls was performed by ultrasonication and the enzymatic digestion with DNase, RNase and pronase separately. Crude cell walls were washed with M NaCl and 5% SDS and were isolated by 20,000 g centrifugation. Muropeptide amino acids were freed by hydrolysis at 121C for 10 minutes in 6N HCl.

Detection of Rhizobium japonicum murein layer amino acids was done by 2-dimensional instant thin layer chromatography on silica gel plates. The solvents found most favorable, were n-butanol: acetic acid: water and n-propanol: 34% ammonium hydroxide. Amino acid spots were developed by spraying ninhydrin on the chromatograms, …

The Role Of D-Gluconic Acid In The Regulation Of The Synthesis Of The Enzymes Of The Entner-Doudoroff Pathway In Pseudomonas Fluorescens, Steven C. Quay

Honors Theses

Induction of Entner-Duodoroff pathway enzymes in Pseudomonas fluorescens was investigated to study the role of gluconate as a possible inducer. Glucose oxidase-deficient mutants were isolated and characterized. One of these mutants, gox-7, was deficient in particulate glucose oxidase; another mutant, gox-17, was deficient in particulate glucose and gluconate oxidase activities. Gluconate, but not glucose, induced synthesis of gluconokinase and 6-phosphogluconate dehydratase in both mutants. High constitute levels of 2-keto-3-deoxy-6-phosphogluconate aldolase were found when both mutants were grown on glucose. Growth of parent and both mutant strains on glycerol also resulted in high levels of Entner-Doudoroff pathway enzymes. It was concluded …

Lysis Of The Rhizobiaceae, Craig Richard Baumrucker

Masters Theses

The following members of the Rhizobiaceae were tested for their lytic response to various treatments: Agrobacterium tumefaciens, Chromobacterium violaceum, Rhizobium phaseoli, Rhizobium trifolii, Rhizobium lupini, and Rhizobium japonicum. Lysis was observed in spent growth media and as a function of saline concentration, pH, buffer composition, disodium (ethylenedinitrilo) tetraacetate (EDTA) concentration, and lysozyme.

Cells were harvested by centrifugation, washed, and resuspended in various treatment solutions. The lytic response was followed spectrophotometrically.

The different responses of the six cultures was applied to a summation of reclassification proposals evolved through modern taxonomic techniques such as DNA homology …