Microbiology Commons^™

Understanding The Role Of Estrogen In The Mucosal Immune Response, Youna Choi, Dr. Eric Wilson

Journal of Undergraduate Research

Most antigens (foreign substances) enter an organism via mucosal surfaces. Thus, understanding the mechanisms involved in immune protection at these surfaces is of paramount importance. Immune responses are highly dependent on homing mechanisms responsible for directing lymphocyte (white blood cell) migration and accumulation at target tissues. Estrogen control of lymphocyte homing within the uterus has recently been established (2).

High Salinity Stabilizes Bacterial Community Composition And Activity Through Time, Tylan Wayne Magnusson

Theses and Dissertations

Dormancy is a plausible strategy for bacteria to overcome the effects of temporal fluctuations in resources or stresses and await more “optimal” conditions to resume metabolic activity and growth. Seasonal changes in environmental conditions force microbes to adjust their metabolic activity accordingly, and community composition drastically shifts. In extreme environments, however, the overriding effects of a constant stress may constrain the need or benefit of bacteria entering dormancy. In hypersaline lakes, high metabolic activity is required to maintain adaptations that permit survival. Sampling from six lakes on a salinity gradient (0.05% – 30.3%), we measured seasonal fluctuations in bacterial dormancy …

Isquest: Finding Insertion Sequences In Prokaryotic Sequence Fragment Data, Abhishek Biswas, David T. Gauthier, Desh Ranjan, Mohammad Zubair

Computer Science Faculty Publications

Motivation: Insertion sequences (ISs) are transposable elements present in most bacterial and archaeal genomes that play an important role in genomic evolution. The increasing availability of sequenced prokaryotic genomes offers the opportunity to study ISs comprehensively, but development of efficient and accurate tools is required for discovery and annotation. Additionally, prokaryotic genomes are frequently deposited as incomplete, or draft stage because of the substantial cost and effort required to finish genome assembly projects. Development of methods to identify IS directly from raw sequence reads or draft genomes are therefore desirable. Software tools such as Optimized Annotation System for Insertion Sequences …

Isolation And Epidemiological Analysis Of Verotoxigenic E. Coli From Patients With Acute Gastroenteritis: A Prospective Study Aiming To Reduce The Burden Of Infection In The Cork Region., Shirley Ross

Masters

Verotoxigenic Escherichia coli (VTEC) is a serious gastrointestinal pathogen associated with morbidity and mortality in the first world, as accentuated by the O104 VTEC outbreak in Germany in 2011. Molecular detection of Verotoxin (VT) has increased the detection of VTEC across Europe however, Ireland still has the highest incidence and isolation is still a key step in the confirmation of infection and the control and prevention of outbreaks. Currently no standard protocol exists for the detection, isolation and characterisation of non-O157 VTEC and it is feared that due to this that the prevalence of VTEC is under-reported. This body of …

Microbial Community Analysis From Petroleum-Contaminated Sediments With High Magnetic Susceptibility, Anja E. Williams

Masters Theses

Microbial biodegradation is an increasingly incorporated method of hydrocarbon mineralization during oil spill cleanup. To monitor biodegradation, magnetic susceptibility (MS) is a geophysical tool that detects changes in sediments’ magnetism, possibly caused by microbial activity, for example by anaerobic iron reduction that can induce magnetite formation. Furthermore, the high input of carbon from an oil spill makes other required nutrients, like nitrogen, limiting. The first study goal was to characterize the microbial communities present at high levels of MS with 16S rRNA gene clone libraries at the petroleum-contaminated site in Bemidji, Minnesota. Sequences with high similarity to known iron-reducers were …

Genetic Changes To A Transcriptional Silencer Element Confers Phenotypic Diversity Within And Between Drosophila Species, Winslow C. Johnson, Alison J. Ordway, Masayoshi Watada, Jonathan N. Pruitt, Thomas M. Williams, Mark Rebeiz

Biology Faculty Publications

The modification of transcriptional regulation has become increasingly appreciated as a major contributor to morphological evolution. However, the role of negative-acting control elements (e.g. silencers) in generating morphological diversity has been generally overlooked relative to positive-acting “enhancer” elements. The highly variable body coloration patterns among Drosophilid insects represents a powerful model system in which the molecular alterations that underlie phenotypic diversity can be defined. In a survey of pigment phenotypes among geographically disparate Japanese populations of Drosophila auraria, we discovered a remarkable degree of variation in male-specific abdominal coloration. In testing the expression patterns of the major pigment-producing enzymes, …

Secretion Of Heat-Labile Enterotoxin By Porcine-Origin Enterotoxigenic Escherichia Coli And Relation To Virulence, Prageeth Rukshan Wijemanne

School of Veterinary and Biomedical Sciences: Dissertations, Theses, and Student Research

Heat-labile enterotoxin (LT) is an important virulence factor secreted by some strains of porcine-origin enterotoxigenic Escherichia coli (pETEC). The prototypic human-origin strain H10407 secretes LT via a type II secretion system (T2SS), but its presence or importance in pETEC has not been established. Exposure of pETEC to glucose has been shown to result in different secretion levels of LT. Furthermore, the relationship between the level of LT secreted and the virulence potential of the respective pETEC strain has not been established. To determine the relationship between the capacity to secrete LT and virulence in wild-type (WT) pETEC, 16 strains isolated …

The Antioxidant And Dna Repair Capacities Of Resveratrol, Piceatannol, And Pterostilbene, Justin Ryan Livingston

Theses and Dissertations

Lifestyle diseases represent a large burden on developed societies and account for much morbidity worldwide. Research has shown that eating a diet rich in fruit and vegetables helps to ameliorate and prevent some of these diseases. Antioxidants found in fruits and vegetables may provide a substantial benefit in reducing disease incidence. This thesis examines the antioxidant properties of resveratrol, piceatannol, and pterostilbene, and the ability of Burkitt's Lymphoma (Raji) cells to uptake these three antioxidants. It also studies the effect of the antioxidants in protecting against DNA damage and their role in DNA repair following oxygen radical exposure in Raji …

Identifying And Characterizing Yeast Pas Kinase 1 Substrates Reveals Regulation Of Mitochondrial And Cell Growth Pathways, Desiree Demille

Theses and Dissertations

Glucose allocation is an important cellular process that is misregulated in the interrelated diseases obesity, diabetes and cancer. Cells have evolved critical mechanisms for regulating glucose allocation, one of which is sensory protein kinases. PAS kinase is a key sensory protein kinase that regulates glucose allocation in yeast, mice and man; and is a novel therapeutic target for the treatment of metabolic diseases such as obesity, diabetes and cancer. Despite its importance, the molecular mechanisms of PAS kinase function are largely unknown. Through large-scale protein-interaction studies, we have identified 93 novel binding partners for PAS kinase which help to expand …

The Biological Consequences Of Kaolin Geophagia, Deloris Alexander, Desire Richardson, Lakisha Odom, Kara Cromwell, Dejuana Grant, Micoya Myers, Eddy Cadet, Hamid Mahama, Vijaya Rangari, Ralphenia Pace, Ramble Ankumah, Kokoasse Kpomblekou-A, Curtis Fluker

Professional Agricultural Workers Journal

Abstract

Kaolin geophagia is associated with the relief of gastrointestinal distress, but it may also cause adverse health effects on the body. This study was designed to: assess kaolin composition; test if 129SvEv mice would consume kaolin and determine the consequences of consumption; and assess rotational stress modulation of consumption. Thirteen kaolin samples were purchased from Alabama and Georgia stores. Chemical and physical properties were characterized for each sample using a Munsell chart, pH meter, Energy Dispersive Spectroscopy, Transmission Electron Microscopy, Visible Near-InfraRed Spectra, and Inductively Coupled Plasma-Optical Emission Spectrometry. Kaolin was then given to mice as food supplements and …

Isolation And Host Range Of Staphylococcus Aureus Bacteriophages And Use For Decontamination Of Fomites, Kyle C. Jensen

Theses and Dissertations

Staphylococcus aureus is a common bacterium found on the skin and mucosal membranes of about 20% of the population. S. aureus growth on the skin is harmless, but if it bypasses the skin it can causes life-threatening diseases such as pneumonia, meningitis, bacteremia, and sepsis. Antibiotic-resistant strains of S. aureus, called Methicillin Resistant S. aureus (MRSA), are resistant to most antibiotics except vancomycin. However, vancomycin resistant strains of MRSA are becoming more common. In this study, 12 phages were isolated capable of infecting human S. aureus and/or MRSA strains. Five phages were discovered through mitomycin C induction of prophages and …

Fungi Inhabiting The Healthy Human Gastrointestinal Tract: A Diverse And Dynamic Community, Heather E. Hallen-Adams, Stephen D. Kachman, Jaehyoung Kim, Ryan Legge, Inés Martínez

Department of Food Science and Technology: Faculty Publications

Fungal DNA was selectively amplified, and the ITS region sequenced, from fecal samples taken from 45 healthy human volunteers at one (21 volunteers) or two (24 volunteers) time points. Seventy-two operational taxonomic units, representing two phyla and ten classes of fungi, were recovered. Candida yeasts, notably C. tropicalis (present in 51 samples), and yeasts in the Dipodascaceae (39 samples), dominated, while 38 OTUs were detected in a single sample each. Fungi included known human symbionts (Candida, Cryptococcus, Malassezia and Trichosporon spp.), common airborne fungi (Cladosporium sp.) and fungi known to be associated with food ( …

Virulence Gene Expression Of Vibrio Parahaemolyticus In The Viable But Nonculturable State, Tiffany Pui-Yun Tse

Master's Theses

Vibrio parahaemolyticus is a food-borne pathogen commonly associated with the consumption of raw or undercooked seafood resulting in primary infections of the human gastrointestinal tract. It is estimated to cause about 4500 illnesses each year in the United States. However, infection from this food-borne pathogen can be avoided if this organism is detected in the implicated food, prior to consumption. Current standard methods of detecting this organism are dependent on the culturability of the bacteria. Detection based on an organism’s culturability may be problematic as V. parahaemolyticus has been known to exist in a viable but nonculturable (VBNC) state. Bacteria …

Advancing Phage Genomics And Honeybee Health Through Discovery And Characterization Of Paenibacillaceae Bacteriophages, Bryan Douglas Merrill

Theses and Dissertations

The Paenibacillaceae family of bacteria includes two species known to infect the hives of honeybees, Paenibacillus larvae and Brevibacillus laterosporus. P. larvae, the causative agent of American Foulbrood (AFB) causes a lethal infection of honeybee larvae, while B. laterosporus is a secondary invader following European Foulbrood (EFB) infection. Increasing antibiotic resistance of P. larvae bacteria has prompted a search for alternative treatment methods for this disease. Bacteriophages are the most diverse life forms on earth and can provide important insights about the bacterial hosts they infect. However, few Paenibacillaceae phages have been isolated or characterized. In this study, the first …

Generation And Assessment Of Muscular Mutations In Caenorhabditis Elegans, Katie N. Reget

DePaul Discoveries

A study of egg laying muscular mutations in C. elegans was conducted over a span of ten weeks. Parent (EGL-19) and wild type (N2) were exposed to mutagenesis and integration mutation techniques to generate genetic and physical different mutants. Overall, four genetic, physical and phenotypically unique worms were generated for the process of mutagenesis. The worms used in the process of integration were found to have shortened life spans, reduced size and decrease numbers of progeny.

Chronic Inflammation As A Result Of Hepatitis C Virus Infection: A Review Of The Literature, Samantha L. Lane

DePaul Discoveries

Approximately 170 million people are infected with Hepatitis C virus (HCV) worldwide^5,6. It is estimated that roughly 80% of those infected suffer from persistent infection with the virus; this persistence of infection is progressive, and over time can lead to fibrosis, cirrhosis, and hepatocellular carcinoma⁷. Chronic inflammation and apoptotic deregulation are both hallmarks of chronic HCV infection, and many molecular pathways are initiated in both the innate and adaptive immune responses during infection with this viral pathogen. The aim of this review was to survey some of the major molecular mechanisms responsible for the induction of …

Analysis Of Anti-Dengue Antibodies, Lauren Syndergaard, Brian Poole

Journal of Undergraduate Research

Dengue virus is a mosquitoes-borne virus that causes dengue fever. It is found primarily in tropical areas with over a third of the world’s population living in at-risk areas (WHO). The number of infections has grown rapidly in recent years with as many as 50 to 100 million infections occur each year (WHO). Though not widely present in the United States (small outbreaks occur with some regularity in Texas from the Mexican border; Hawaii and Florida relatively recently had cases), many travelers endemic areas contract the virus. Though several are being studied, as yet, there are no vaccines available for …

Engineering A Pathogen Specific High Affinity T-Cell Receptor Called Llo56, John Hancock, Dr. Scott Weber

Journal of Undergraduate Research

CD4+ helper T-cells play a vital role in the body’s immune response. When infectious agents attack the body, phagocytes engulf these invaders and present a peptide segment of the pathogen on a receptor (called MHCII). These receptors are located on the surface of the cell and the displayed peptide is termed an epitope. CD4+ T-cells with T-cell receptors (TCRs) specific for the displayed peptide bind to the MHCII complex. It is this binding that releases chemical signals to initiate an immune response. A disadvantage of TCRs is that their wild-type affinity for MHC is low and that they are membrane …

Discovery And Characterization Of Bacteriophage To Control Mrsa, Jacob B. Hatch, Bradford Berges

Journal of Undergraduate Research

About 20% of humans are carriers of Staphylococcus aureus (SA). There were an estimated 11,000 deaths in the United States in 2005 attributed to SA, with the majority caused by MRSA (Methicillin Resistant Staphylococcus Aureus) isolates [1]. Many MRSA isolates have developed resistance to all but one antibiotic drug: vancomycin. However, other bacteria have developed resistance to vancomycin, suggesting that in time MRSA will likewise become non-responsive to this last available drug and MRSA infections will be untreatable. This project looks to find an alternate method of MRSA treatment. Bacteriophage (phage) are viruses that infect bacterial cells in order …

Use Of Humanized Mice To Study The Production Of Human Antibodies, Steven Hallam, Dr. Bradford Berges

Journal of Undergraduate Research

The human immune system is composed of two main subsets: innate and adaptive immunities. Among the adaptive immune cells, B cells play a vital role in stopping infectious agents through the production of antigen specific antibodies. Human B cells are important targets of infection for many human-specific viruses that are poorly understood. Since the infection and study of human subjects is not possible, animal models have been developed to mimic the human immune environment. Rag2-/-γc-/- mice engrafted with human hematopoietic stem cells produce human B lymphocytes and these cells are capable of mounting antigen-specific human antibody responses. However, there is …

Mapping Interaction Through Compensatory Phou Mutants In Escherichia Coli, Tanner Dean, William Mccleary

Journal of Undergraduate Research

The purpose of this experiment was to identify the physical interaction site between two proteins in Escherichia Coli. These two proteins, PhoU and PhoR, are two proteins involved in Phosphate signal transduction. When these two proteins are mutated, so they no longer interact, the pathway is broken and signaling is inhibited. To break this pathway, we mutated one protein (PhoR) until we developed several mutations that no longer interact with PhoU. This loss of interaction is caused by a physical change to the site of interaction between the two proteins. We hypothesized that we could find a naturally occurring PhoU …

Fire Blight Treatment With Lytic Bacteriophage, Todd Jarvis, Julianne Grose

Journal of Undergraduate Research

Fire Blight, caused by the bacteria Erwinia amylovora, is a highly contagious fruit tree disease that is difficult to treat. This disease causes a tree to whither away, as if it had been burned. It is estimated that Fire Blight causes more than a 100 million dollar loss in agricultural goods each year¹. In an attempt to treat fire blight and prevent it from spreading, large doses of antibiotics are sprayed on infected trees. These antibiotics do little in the way of helping to treat the trees. In addition, the antibiotic run off from the treatment finds …

Lymphoblastoid Cell Line Generation From Sle Patient Lymphocytes, Vera Mayhew, Brian Poole

Journal of Undergraduate Research

Epstein-Barr Virus (EBV) is one of the viruses found most frequently in the human population. Approximately 95% of the population is infected in the United Sates by the age of 40. When primary infection occurs is young adulthood approximately 50% of cases result in infectious mononucleosis. Whether EBV infection results in mononucleosis manifestations or not, the virus stays latent in the infected individual’s B cells for the rest of their life.

How Chemokine Ccl28 Binds To Yersinia Pseudotuberculosis, Jeffrey Moffat, David Erickson

Journal of Undergraduate Research

Chemokines are tiny proteins that play a valuable role in defending our bodies against bacteria and other pathogens. Chemokines are best known for their role in attracting immune cells to areas of infection. Some chemokines, however, have demonstrated the ability to not only recognize pathogens and/or recruit white blood cells, but also to kill various classes of bacteria and fungi¹. One of these antimicrobial chemokines is CCL28.

P. Larvae Bacteriophages As A Treatment For American Foulbrood In Honeybees, Bryan Merrill, Sandra Burnett

Journal of Undergraduate Research

The deadly honey bee disease American Foulbrood (AFB) is caused by the bacterium Paenibacillus larvae. The widespread use of antibiotics to prevent or treat AFB has led to many drug-resistant strains of P. larvae. Bacteriophages can target and destroy specific strains of bacteria and can be used to treat bacterial infections. This study accomplished two main goals. We determined the efficacy of previously isolated P. larvae phages as a treatment for AFB by applying a phage spray to infected beehives. We also isolated P. larvae bacteria from the infected hives we treated and identified phages to better counteract …

Cofactor Specificity Of The Bifunctional Alcohol And Aldehyde Dehydrogenase (Adhe) In Wild-Type And Mutant Clostridium Thermocellum And Thermoanaerobacterium Saccharolyticum, Tianyong Zheng, Daniel G. Olson, Liang Tian, Yannick J. Bomble, Michael Himmel, Jonathan Lo, Shuen Hon, A. Joe Shaw, Johannes P. Van Dijken, Lee Lynd

Dartmouth Scholarship

Clostridium thermocellum and Thermoanaerobacterium saccharolyticum are thermophilic bacteria that have been engineered to produce ethanol from the cellulose and hemicellulose fractions of biomass, respectively. Although engineered strains of T. saccharolyticum produce ethanol with a yield of 90% of the theoretical maximum, engineered strains of C. thermocellum produce ethanol at lower yields (∼50% of the theoretical maximum). In the course of engineering these strains, a number of mutations have been discovered in their adhE genes, which encode both alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) enzymes. To understand the effects of these mutations, the adhE genes from six strains of C. …

Effect Of Ebi2 On B Cell Migration, Jeffrey Mella, Brian Poole

Journal of Undergraduate Research

My mentored research project was a terrific experience. I have been mentored with Dr. Brian Poole for the last three years. As a result of the project that was made possible by the ORCA grant, I was the first author on an abstract submitted and accepted by the International Immunology Summit. This last October I attended the International Immunology Summit in Las Vegas, Nevada. Dr. Poole and I presented our research and I responded to questions from the audience. I am currently an author on a manuscript that in progress that has been submitted for review. I have enjoyed my …

The Effects Of Sustained, High-Velocity Exercise On Gene Expression In California Yellowtail (Seriola Lalandi), Kelli Hatter

Undergraduate Honors Theses

California Yellowtail muscle fibers have been observed to exhibit two drastically different development patterns resulting from the speeds at which they are exercised. When fish are exercised at a moderate rate their epaxial fast-twitch muscle fibers grow in diameter—hypertrophy; when they are exercised at a fast speed, more new epaxial fast-twitch muscle fibers are produced—hyperplasia. To determine the underlying reason for this difference in muscle development, my summer research project and honors thesis exercised fish at: fast, moderate, and control speeds for a sustained amount of time to determine what is happening on a cellular level to cause the observed …

Histone Modifications And Their Effects On Nucleosome Positioning And Gene Expression, Jordon Ritchie, Steven Johnson

Journal of Undergraduate Research

Nucleosome positioning plays an important role in gene regulation and expression. Nucleosomes consist of DNA-histone interactions that comprise the first order of DNA compaction into chromatin in the cell. Modifications to the histone in the nucleosome have been hypothesized to influence the location of the nucleosome on the DNA and therefore the regulation of the gene the nucleosome is forming on. In our original proposal, we proposed to show the effects that different modifications had on the position of the nucleosome on the DNA and the DNA sequence that had the highest affinity for nucleosome formation given a specific histone …

Analysis Of The Adjuvant Effect Of Vitamin D3 In Enhancing Mucosal Immune Responses, Cameron Sargent, Dr. Eric Wilson

Journal of Undergraduate Research

Because skin provides an effective physical barrier, most pathogens that invade the body do so at mucosal sites like the nose and mouth. As such, finding methods of improving mucosal immunity is key to providing greater defense against communicable diseases, the cause of approximately one-quarter of all deaths worldwide [1]. Improving vaccination, the technique in which the body is exposed to a weakened or nonvirulent dosage of a pathogen or toxin to promote an immune response specific to that foreign material, is a potential way of enhancing mucosal immunity. Vaccination has been used for several decades in medicine, nearly eradicating …