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Pathogenic Microbiology Commons

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2015

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Articles 1 - 30 of 51

Full-Text Articles in Pathogenic Microbiology

Protection Against Experimental Cryptococcosis Following Vaccination With Glucan Particles Containing Cryptococcus Alkaline Extracts, Charles A. Specht, Chrono K. Lee, Haibin Huang, Donald J. Tipper, Zu T. Shen, Jennifer K. Lodge, John D. Leszyk, Gary R. Ostroff, Stuart M. Levitz Dec 2015

Protection Against Experimental Cryptococcosis Following Vaccination With Glucan Particles Containing Cryptococcus Alkaline Extracts, Charles A. Specht, Chrono K. Lee, Haibin Huang, Donald J. Tipper, Zu T. Shen, Jennifer K. Lodge, John D. Leszyk, Gary R. Ostroff, Stuart M. Levitz

Infectious Diseases and Immunology Publications and Presentations

A vaccine capable of protecting at-risk persons against infections due to Cryptococcus neoformans and Cryptococcus gattii could reduce the substantial global burden of human cryptococcosis. Vaccine development has been hampered though, by lack of knowledge as to which antigens are immunoprotective and the need for an effective vaccine delivery system. We made alkaline extracts from mutant cryptococcal strains that lacked capsule or chitosan. The extracts were then packaged into glucan particles (GPs), which are purified Saccharomyces cerevisiae cell walls composed primarily of β-1,3-glucans. Subcutaneous vaccination with the GP-based vaccines provided significant protection against subsequent pulmonary infection with highly virulent ...


Changes In Gut And Plasma Microbiome Following Exercise Challenge In Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (Me/Cfs), Sanjay K. Shukla, Dane B. Cook, Jacob Meyer, Suzanne D. Vernon, Thảo Lê, Derek Clevidence, Charles E. Robertson, Steven J. Schrodi, Steven Yale, Daniel N. Frank Dec 2015

Changes In Gut And Plasma Microbiome Following Exercise Challenge In Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (Me/Cfs), Sanjay K. Shukla, Dane B. Cook, Jacob Meyer, Suzanne D. Vernon, Thảo Lê, Derek Clevidence, Charles E. Robertson, Steven J. Schrodi, Steven Yale, Daniel N. Frank

Jacob Meyer

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a disease characterized by intense and debilitating fatigue not due to physical activity that has persisted for at least 6 months, post-exertional malaise, unrefreshing sleep, and accompanied by a number of secondary symptoms, including sore throat, memory and concentration impairment, headache, and muscle/joint pain. In patients with post-exertional malaise, significant worsening of symptoms occurs following physical exertion and exercise challenge serves as a useful method for identifying biomarkers for exertion intolerance. . Evidence suggests that intestinal dysbiosis and systemic responses to gut microorganisms may play a role in the symptomology of ME ...


Data From: A Higher Activation Threshold Of Memory Cd8+ T Cells Has A Fitness Cost That Is Modified By Tcr Affinity During Tuberculosis, Stephen M. Carpenter, Claudio Nunes-Alves, Matthew G. Booty, Sing Sing Way, Samuel M. Behar Dec 2015

Data From: A Higher Activation Threshold Of Memory Cd8+ T Cells Has A Fitness Cost That Is Modified By Tcr Affinity During Tuberculosis, Stephen M. Carpenter, Claudio Nunes-Alves, Matthew G. Booty, Sing Sing Way, Samuel M. Behar

MaPS Research Data

Manuscript abstract: T cell vaccines against Mycobacterium tuberculosis (Mtb) and other pathogens are based on the principle that memory T cells rapidly generate effector responses upon challenge, leading to pathogen clearance. Despite eliciting a robust memory CD8+ T cell response to the immunodominant Mtb antigen TB10.4 (EsxH), we find the increased frequency of TB10.4-specific CD8+ T cells conferred by vaccination to be short-lived after Mtb challenge. To compare memory and naïve CD8+ T cell function during their response to Mtb, we track their expansions using TB10.4-specific retrogenic CD8+ T cells. We find that the primary (naïve) response ...


Design And Testing Of Novel Anthrax Vaccines Utilizing A Tobacco Mosaic Virus Expression System, Ryan C. Mccomb Dec 2015

Design And Testing Of Novel Anthrax Vaccines Utilizing A Tobacco Mosaic Virus Expression System, Ryan C. Mccomb

KGI Theses and Dissertations

Anthrax is a potentially fatal disease caused by the bacteria Bacillus anthracis. Infection and disease occur after spores gain entry into the body, germinate into vegetative bacteria, and produce toxin. Bacillus anthracis spores have been engineered as bioweapons and have been used repeatedly in warfare and terrorism to inflict casualties in military and civilian populations. Currently, only one vaccine has been approved for prevention of anthrax in the United States. This vaccine is an undefined product that is difficult to produce, requires a long vaccination schedule, and is reactogenic. Efforts to make an improved anthrax vaccine are being pursued. With ...


Utilizing Cmp-Sialic Acid Analogs To Unravel Neisseria Gonorrhoeae Lipooligosaccharide-Mediated Complement Resistance And Design Novel Therapeutics, Sunita Gulati, Ian C. Schoenhofen, Dennis M. Whitfield, Andrew D. Cox, Jianjun Li, Frank St Michael, Evgeny V. Vinogradov, Jacek Stupak, Bo Zheng, Makoto Ohnishi, Magnus Unemo, Lisa A. Lewis, Rachel E. Taylor, Corinna S. Landig, Sandra Diaz, George W. Reed, Ajit Varki, Peter A. Rice, Sanjay Ram Dec 2015

Utilizing Cmp-Sialic Acid Analogs To Unravel Neisseria Gonorrhoeae Lipooligosaccharide-Mediated Complement Resistance And Design Novel Therapeutics, Sunita Gulati, Ian C. Schoenhofen, Dennis M. Whitfield, Andrew D. Cox, Jianjun Li, Frank St Michael, Evgeny V. Vinogradov, Jacek Stupak, Bo Zheng, Makoto Ohnishi, Magnus Unemo, Lisa A. Lewis, Rachel E. Taylor, Corinna S. Landig, Sandra Diaz, George W. Reed, Ajit Varki, Peter A. Rice, Sanjay Ram

Open Access Articles

Neisseria gonorrhoeae deploys a novel immune evasion strategy wherein the lacto-N-neotetraose (LNnT) structure of lipooligosaccharide (LOS) is capped by the bacterial sialyltransferase, using host cytidine-5'-monophosphate (CMP)-activated forms of the nine-carbon nonulosonate (NulO) sugar N-acetyl-neuraminic acid (Neu5Ac), a sialic acid (Sia) abundant in humans. This allows evasion of complement-mediated killing by recruiting factor H (FH), an inhibitor of the alternative complement pathway, and by limiting classical pathway activation ("serum-resistance"). We utilized CMP salts of six additional natural or synthetic NulOs, Neu5Gc, Neu5Gc8Me, Neu5Ac9Ac, Neu5Ac9Az, legionaminic acid (Leg5Ac7Ac) and pseudaminic acid (Pse5Ac7Ac), to define structural requirements of Sia-mediated serum-resistance. While ...


Donor Platelet Plasma Components Inactivate Sensitive And Multidrug Resistant Acinetobacter Baumannii Isolates, Chelsea M. Edelblute, Olga N. Pakhomova, Fanying Li, Barbara Y. Hargrave, Loree C. Heller Dec 2015

Donor Platelet Plasma Components Inactivate Sensitive And Multidrug Resistant Acinetobacter Baumannii Isolates, Chelsea M. Edelblute, Olga N. Pakhomova, Fanying Li, Barbara Y. Hargrave, Loree C. Heller

Bioelectrics Publications

Acinetobacter baumannii is an environmentally resilient healthcare-associated opportunistic pathogen responsible for infections at many body sites. In the last 10 years, clinical strains resistant to many or all commonly used antibiotics have emerged globally. With few antimicrobial agents in the pharmaceutical pipeline, new and alternative agents are essential. Platelets secrete a large number of proteins, including proteins with antimicrobial activity. In a previous study, we demonstrated that donor platelet supernatants and plasma significantly inhibited the growth of a reference strain of A. baumannii in broth and on skin. This inhibition appeared to be unrelated to the platelet activation state. In ...


A Lipidomics Approach To The Viral-Host Dynamics Of The Unicellular, Eukaryotic Alga Chlorella Variabilis And Its Viral Pathogen, Pbcv-1, Suzanne Rose Dec 2015

A Lipidomics Approach To The Viral-Host Dynamics Of The Unicellular, Eukaryotic Alga Chlorella Variabilis And Its Viral Pathogen, Pbcv-1, Suzanne Rose

Dissertations and Theses in Biological Sciences

This thesis focuses on the sterol and sphingolipid composition in the unicellular, green alga Chlorella variabilis and the lipidomic changes that occur during viral infection. Using lipid analysis by mass spectrometry, we have identified the major sterol, ergosterol and sphingolipid, glucosyl inositol phosphoceramide (GIPC) as constituents of C. variabilis cell membranes. Sterols and sphingolipids have essential biological functions such as hormone-based signaling, plant defense, and apoptosis as well as critical roles in structural components of the cell and organelle membranes. In chapters two and three, we focus on the characterization of sterol composition among both freshwater and marine alga and ...


Dna-Containing Immunocomplexes Promote Inflammasome Assembly And Release Of Pyrogenic Cytokines By Cd14+ Cd16+ Cd64high Cd32low Inflammatory Monocytes From Malaria Patients, Isabella C. Hirako, Carolina Gallego-Marin, Marco A. Ataide Oswalso Cruz Founda, Warrison A. Andrade, Humberto Gravina, Bruno C. Rocha, Rosane B. De Oliveira, Dhelio B. Pereira, Joseph Vinetz, Betty Diamond, Sanjay Ram, Douglas T. Golenbock, Ricardo T. Gazzinelli Nov 2015

Dna-Containing Immunocomplexes Promote Inflammasome Assembly And Release Of Pyrogenic Cytokines By Cd14+ Cd16+ Cd64high Cd32low Inflammatory Monocytes From Malaria Patients, Isabella C. Hirako, Carolina Gallego-Marin, Marco A. Ataide Oswalso Cruz Founda, Warrison A. Andrade, Humberto Gravina, Bruno C. Rocha, Rosane B. De Oliveira, Dhelio B. Pereira, Joseph Vinetz, Betty Diamond, Sanjay Ram, Douglas T. Golenbock, Ricardo T. Gazzinelli

Open Access Articles

High levels of circulating immunocomplexes (ICs) are found in patients with either infectious or sterile inflammation. We report that patients with either Plasmodium falciparum or Plasmodium vivax malaria have increased levels of circulating anti-DNA antibodies and ICs containing parasite DNA. Upon stimulation with malaria-induced ICs, monocytes express an NF-kappaB transcriptional signature. The main source of IC-induced proinflammatory cytokines (i.e., tumor necrosis factor alpha [TNF-alpha] and interleukin-1beta [IL-1beta])in peripheral blood mononuclear cells from acute malaria patients was found to be a CD14(+) CD16 (FcgammaRIIIA)(+) CD64 (FcgammaRI)(high) CD32 (FcgammaRIIB)(low) monocyte subset. Monocytes from convalescent patients were predominantly of ...


Spectrum Of Histopathological Findings In Postmenopausal Bleeding, Muhammad Usman Tariq, Romana Idress, Ahmed Raheem, Naila Kayani Nov 2015

Spectrum Of Histopathological Findings In Postmenopausal Bleeding, Muhammad Usman Tariq, Romana Idress, Ahmed Raheem, Naila Kayani

Department of Pathology and Laboratory Medicine

Objective:To determine the frequencies of histopathological findings in endometrial and endocervical biopsy samples with clinical history of Postmenopausal Bleeding (PMB). Study Design:Descriptive cross-sectional study. Place and Duration of Study:Section of Histopathology, Department of Pathology and Laboratory Medicine, The Aga Khan University Hospital, Karachi, from February 2012 to January 2013. Methodology:Atotal of 157 consecutive endometrial and endocervical biopsy specimens with history of postmenopausal bleeding were included. After microscopic examination, frequencies of histological findings in different age groups were generated. Chi-square and independent sample t-tests were applied to see whether the difference was significant which was set at ...


The Epithelial Transmembrane Protein Perp Is Required For Inflammatory Responses To S. Typhimurium Infection: A Dissertation, Kelly N. Hallstrom Oct 2015

The Epithelial Transmembrane Protein Perp Is Required For Inflammatory Responses To S. Typhimurium Infection: A Dissertation, Kelly N. Hallstrom

GSBS Dissertations and Theses

Salmonella enterica subtype Typhimurium (S. Typhimurium) is one of many non-typhoidal Salmonella enterica strains responsible for over one million cases of salmonellosis in the United States each year. These Salmonella strains are also a leading cause of diarrheal disease in developing countries. Nontyphoidal salmonellosis induces gastrointestinal distress that is characterized histopathologically by an influx of polymorphonuclear leukocytes (PMNs), the non-specific effects of which lead to tissue damage and contribute to diarrhea.

Prior studies from our lab have demonstrated that the type III secreted bacterial effector SipA is a key regulator of PMN influx during S. Typhimurium infection and that its ...


Regulation Of Vancomycin Resistance And Stress Response By The Msaabcr Operon In Staphylococcus Aureus, Dhritiman Samanta Aug 2015

Regulation Of Vancomycin Resistance And Stress Response By The Msaabcr Operon In Staphylococcus Aureus, Dhritiman Samanta

Dissertations

Staphylococcus aureus is the predominant cause of public health problems around the world. Vancomycin has been an important antibiotic against Methicillin Resistant Staphylococcus aureus (MRSA) infections. However, Vancomycin Intermediate S. aureus (VISA) strains have been reported. These strains are characterized by thick cell walls, reduced autolytic rate, reduced PBP4 activity, and increased amount of D-Ala-D-Ala termini in the cell wall. In this study, we show that the msaABCR operon regulates vancomycin resistance in two clinical VISA strains. Deletion of the msaABCR operon in strains Mu50 and HIP6297 resulted in a significant decrease in the minimum inhibitory concentration (MIC) for vancomycin ...


Rnasek Is A V-Atpase-Associated Factor Required For Endocytosis And The Replication Of Rhinovirus, Influenza A Virus, And Dengue Virus, Jill Perreira, Aaron Aker, George Savidis, Christopher R. Chin, William M. Mcdougall, Jocelyn M. Portmann, Paul Meraner, Miles Smith, Motiur Rahman, Richard E. Baker, Annick Gauthier, Michael Franti, Abraham L. Brass Aug 2015

Rnasek Is A V-Atpase-Associated Factor Required For Endocytosis And The Replication Of Rhinovirus, Influenza A Virus, And Dengue Virus, Jill Perreira, Aaron Aker, George Savidis, Christopher R. Chin, William M. Mcdougall, Jocelyn M. Portmann, Paul Meraner, Miles Smith, Motiur Rahman, Richard E. Baker, Annick Gauthier, Michael Franti, Abraham L. Brass

Open Access Articles

Human rhinovirus (HRV) causes upper respiratory infections and asthma exacerbations. We screened multiple orthologous RNAi reagents and identified host proteins that modulate HRV replication. Here, we show that RNASEK, a transmembrane protein, was needed for the replication of HRV, influenza A virus, and dengue virus. RNASEK localizes to the cell surface and endosomal pathway and closely associates with the vacuolar ATPase (V-ATPase) proton pump. RNASEK is required for endocytosis, and its depletion produces enlarged clathrin-coated pits (CCPs) at the cell surface. These enlarged CCPs contain endocytic cargo and are bound by the scissioning GTPase, DNM2. Loss of RNASEK alters the ...


The Role Of Phosphatidylserine And Phosphatidylethanolamine In Candida Albicans Virulence, Sarah Elizabeth Davis Aug 2015

The Role Of Phosphatidylserine And Phosphatidylethanolamine In Candida Albicans Virulence, Sarah Elizabeth Davis

Doctoral Dissertations

In hospitalized patients with neutropenia, Candida albicans is the fourth leading cause of systemic bloodstream infections, which have a mortality rate of approximately 30 %. The phosphatidylserine synthase enzyme of C. albicans, Cho1p, appears to be a good drug target as a mutant lacking this enzyme (the cho1Δ/Δ [null mutant]) is avirulent in animal models of Candida infections and this enzyme is not conserved in humans. We discovered that the loss of phosphatidylserine (PS) synthesis affects C. albicans' expression of the Als3p adhesin, a virulence protein, and loss of PS synthesis also compromises the cell wall, causing increased exposure ...


Algr Directly Controls Rsma In Pseudomonas Aeruginosa, Tyler Speaks Aug 2015

Algr Directly Controls Rsma In Pseudomonas Aeruginosa, Tyler Speaks

Electronic Theses and Dissertations

Pseudomonas aeruginosa is a bacterial pathogen that can infect any human tissue. The lungs of cystic fibrosis patients become chronically infected with Pseudomonas aeruginosa. Virulence factor gene expression is under elaborate regulatory control that remains poorly characterized. Understanding the regulatory hierarchy involved during infection is essential for identifying novel drug targets. RsmA is a post-transcriptional regulatory protein that controls expression of several virulence factors. Previous studies demonstrated alginate regulatory components AlgU and AlgR as regulators of rsmA expression. The aim of this study was to determine how AlgR controls rsmA expression. Western blot analysis of HA-tagged RsmA confirmed lower RsmA ...


Prevalence Of A Chytrid Pathogen (Batrachochytrium Dendrobatidis) In Eastern Hellbender Salamanders In New York And Pennsylvania, Linxuan Wu Aug 2015

Prevalence Of A Chytrid Pathogen (Batrachochytrium Dendrobatidis) In Eastern Hellbender Salamanders In New York And Pennsylvania, Linxuan Wu

Biology Theses

Amphibian populations are currently declining globally. There are many possible causes for these declines, among which an emerging infectious disease, chytridiomycosis, has been implicated. Chytridiomycosis in the U.S.A. is mainly caused by the Batrachochytrium dendrobatidis. In this study, I used qPCR assays to detect the existence of this pathogen in the Eastern Hellbender (Cryptobranchus alleganiensis alleganiensis) populations in the Allegheny and Susquehanna River drainages of New York and Pennsylvania. Chytrid is most often tested by using skin swabs, but in this study, tail clips, dorsal skin, blood and eggs were tested as well. Batrachochytrium dendrobatidis was detected in ...


Investigations Of Filarial Nematode Motility, Response To Drug Treatment, And Pathology, Charles Nutting Aug 2015

Investigations Of Filarial Nematode Motility, Response To Drug Treatment, And Pathology, Charles Nutting

Dissertations

More than a billion people live at risk of chronic diseases caused by parasitic filarial nematodes. These diseases: lymphatic filariasis, onchocerciasis, and loaisis cause significant morbidity, degrading the health, quality of life, and economic productivity of those who suffer from them. Though treatable, there is no cure to rid those infected of adult parasites. The parasites can modulate the immune system and live for 10-15 years. Testing of compounds against filarial nematodes is complicated due to a lack of an objective platform on which to analyze in vitro treatments. There is no published, immunocompetent laboratory model for lymphatic filariasis. This ...


Eif2alpha Confers Cellular Tolerance To S. Aureus Alpha-Toxin, Gisela Von Hoven, Claudia Neukirch, Martina Meyenburg, Sabine Fuser, Maria Bidna Petrivna, Amable J. Rivas, Alexey Ryazanov, Randal J. Kaufman, Raffi V. Aroian, Matthias Husmann Jul 2015

Eif2alpha Confers Cellular Tolerance To S. Aureus Alpha-Toxin, Gisela Von Hoven, Claudia Neukirch, Martina Meyenburg, Sabine Fuser, Maria Bidna Petrivna, Amable J. Rivas, Alexey Ryazanov, Randal J. Kaufman, Raffi V. Aroian, Matthias Husmann

Open Access Articles

We report on the role of conserved stress-response pathways for cellular tolerance to a pore forming toxin. First, we observed that small molecular weight inhibitors including of eIF2alpha-phosphatase, jun-N-terminal kinase (JNK), and PI3-kinase sensitized normal mouse embryonal fibroblasts (MEFs) to the small pore forming S. aureus alpha-toxin. Sensitization depended on expression of mADAM10, the murine ortholog of a proposed high-affinity receptor for alpha-toxin in human cells. Similarly, eIF2alpha (S51A/S51A) MEFs, which harbor an Ala knock-in mutation at the regulated Ser51 phosphorylation site of eukaryotic translation initiation factor 2alpha, were hyper-sensitive to alpha-toxin. Inhibition of translation with cycloheximide did not ...


Virulence Of Group A Streptococci Is Enhanced By Human Complement Inhibitors, David Ermert, Jutamas Shaughnessy, Thorsten Joeris, Jakub Kaplan, Catherine J. Pang, Evelyn A. Kurt-Jones, Peter A. Rice, Sanjay Ram, Anna M. Blom Jul 2015

Virulence Of Group A Streptococci Is Enhanced By Human Complement Inhibitors, David Ermert, Jutamas Shaughnessy, Thorsten Joeris, Jakub Kaplan, Catherine J. Pang, Evelyn A. Kurt-Jones, Peter A. Rice, Sanjay Ram, Anna M. Blom

Open Access Articles

Streptococcus pyogenes, also known as Group A Streptococcus (GAS), is an important human bacterial pathogen that can cause invasive infections. Once it colonizes its exclusively human host, GAS needs to surmount numerous innate immune defense mechanisms, including opsonization by complement and consequent phagocytosis. Several strains of GAS bind to human-specific complement inhibitors, C4b-binding protein (C4BP) and/or Factor H (FH), to curtail complement C3 (a critical opsonin) deposition. This results in diminished activation of phagocytes and clearance of GAS that may lead to the host being unable to limit the infection. Herein we describe the course of GAS infection in ...


Prokaryotic Diversity In The Rhizosphere Of Organic, Intensive, And Transitional Coffee Farms In Brazil, Adam Caldwell, Livia Silva, Cynthia Da Silva, Cleber Ouverney Jun 2015

Prokaryotic Diversity In The Rhizosphere Of Organic, Intensive, And Transitional Coffee Farms In Brazil, Adam Caldwell, Livia Silva, Cynthia Da Silva, Cleber Ouverney

Faculty Publications

Despite a continuous rise in consumption of coffee over the past 60 years and recent studies showing positive benefits linked to human health, intensive coffee farming practices have been associated with environmental damage, risks to human health, and reductions in biodiversity. In contrast, organic farming has become an increasingly popular alternative, with both environmental and health benefits. This study aimed to characterize and determine the differences in the prokaryotic soil microbiology of three Brazilian coffee farms: one practicing intensive farming, one practicing organic farming, and one undergoing a transition from intensive to organic practices. Soil samples were collected from 20 ...


Prokaryotic Diversity In The Rhizosphere Of Organic, Intensive, And Transitional Coffee Farms In Brazil, Adam Collins Caldwell, Livia Carneiro Fidéles Silva, Cynthia Canêdo Da Silva, Cleber C. Ouverney Jun 2015

Prokaryotic Diversity In The Rhizosphere Of Organic, Intensive, And Transitional Coffee Farms In Brazil, Adam Collins Caldwell, Livia Carneiro Fidéles Silva, Cynthia Canêdo Da Silva, Cleber C. Ouverney

Cleber C. Ouverney

Despite a continuous rise in consumption of coffee over the past 60 years and recent studies showing positive benefits linked to human health, intensive coffee farming practices have been associated with environmental damage, risks to human health, and reductions in biodiversity. In contrast, organic farming has become an increasingly popular alternative, with both environmental and health benefits. This study aimed to characterize and determine the differences in the prokaryotic soil microbiology of three Brazilian coffee farms: one practicing intensive farming, one practicing organic farming, and one undergoing a transition from intensive to organic practices. Soil samples were collected from 20 ...


Streptococcus Pyogenes Superantigens: Studies Into Host Specificity And Functional Redundancy, Adrienne T. Wakabayashi Jun 2015

Streptococcus Pyogenes Superantigens: Studies Into Host Specificity And Functional Redundancy, Adrienne T. Wakabayashi

Electronic Thesis and Dissertation Repository

Streptococcus pyogenes is a human-specific globally prominent bacterial pathogen that secretes extremely potent exotoxins known as superantigens. Superantigens function to overstimulate T lymphocytes, capable of inducing excessive cytokine responses, potentially leading to toxic shock syndrome. Each strain of S. pyogenes encodes multiple distinct superantigens, yet the reasons why S. pyogenes retains multiple superantigens has remained elusive. Using a murine model of acute nasopharyngeal infection, the role of each superantigen encoded by S. pyogenes MGAS5005 was evaluated using isogenic superantigen-deletion or -complemented strains, and passive immunization with superantigen-neutralizing antibodies. The superantigen SpeG, and likely SpeJ, were not required for infection. However ...


Human Sewage Identified As Likely Source Of White Pox Disease Of The Threatened Caribbean Elkhorn Coral, Kathryn Sutherland, James Porter, Jeffrey Turner, Brian Thomas, Erin Looney, Trevor Luna, Meredith Meyers, J. Futch, Erin Lipp Jun 2015

Human Sewage Identified As Likely Source Of White Pox Disease Of The Threatened Caribbean Elkhorn Coral, Kathryn Sutherland, James Porter, Jeffrey Turner, Brian Thomas, Erin Looney, Trevor Luna, Meredith Meyers, J. Futch, Erin Lipp

Kathryn Patterson Sutherland PhD

Caribbean elkhorn coral, Acropora palmata, has been decimated in recent years, resulting in the listing of this species as threatened under the United States Endangered Species Act. A major contributing factor in the decline of this iconic species is white pox disease. In 2002, we identified the faecal enterobacterium, Serratia marcescens, as an etiological agent for white pox. During outbreaks in 2003 a unique strain of S. marcescens was identified in both human sewage and white pox lesions. This strain (PDR60) was also identified from corallivorious snails (Coralliophila abbreviata), reef water, and two non-acroporid coral species, Siderastrea siderea and Solenastrea ...


Virulence Gene Expression Of Vibrio Parahaemolyticus In The Viable But Nonculturable State, Tiffany Pui-Yun Tse Jun 2015

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

Master's Theses and Project Reports

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 ...


The Shellfish Corner -- Vibrios And Shellfish, Michael Rice May 2015

The Shellfish Corner -- Vibrios And Shellfish, Michael Rice

Michael A Rice

Pathogenic Vibrios are becoming an increasing problem for shellfish producers in North America and elsewhere. This paper reviews current research into the pathogenic nature of Vibrios and provides some practical advice for avoiding the propagation of Vibrios on shellfish farms nd in wild harvest molluscan shellfish.


Transduction As The Method Of Horizontal Gene Transfer Of The Staphylococcal Chromosomal Cassette Mec (Sccmec), Amber B. Sauder May 2015

Transduction As The Method Of Horizontal Gene Transfer Of The Staphylococcal Chromosomal Cassette Mec (Sccmec), Amber B. Sauder

Senior Honors Projects, 2010-current

Methicillin-resistant Staphylococcus aureus (MRSA) gains resistance to β-lactam antibiotics through a mutated penicillin binding protein (PBP2a) encoded on the SCCmec element. In combination with the recombinase encoded by ccr, these two genes are used as markers of the mobile genetic element (SCCmec). Due to recent increases in community acquired MRSA infections, the mechanisms of antibiotic resistance gene transfer have gained attention. Transduction, a method of horizontal gene transfer mediated by bacteriophage, is believed to be responsible for the movement of the SCCmec element. Recent studies have shown the transduction of the SCCmec element in clinical isolates; however, this study is ...


Human And Murine Clonal Cd8+ T Cell Expansions Arise During Tuberculosis Because Of Tcr Selection, Claudio Nunes-Alves, Matthew G. Booty, Stephen M. Carpenter, Alissa C. Rothchild, Constance J. Martin, Danielle Desjardins, Katherine Steblenko, Henrik N. Kløverpris, Rajhmun Madansein, Duran Ramsuran, Alasdair Leslie, Margarida Correia-Neves, Samuel M. Behar May 2015

Human And Murine Clonal Cd8+ T Cell Expansions Arise During Tuberculosis Because Of Tcr Selection, Claudio Nunes-Alves, Matthew G. Booty, Stephen M. Carpenter, Alissa C. Rothchild, Constance J. Martin, Danielle Desjardins, Katherine Steblenko, Henrik N. Kløverpris, Rajhmun Madansein, Duran Ramsuran, Alasdair Leslie, Margarida Correia-Neves, Samuel M. Behar

Microbiology and Physiological Systems Publications and Presentations

The immune system can recognize virtually any antigen, yet T cell responses against several pathogens, including Mycobacterium tuberculosis, are restricted to a limited number of immunodominant epitopes. The host factors that affect immunodominance are incompletely understood. Whether immunodominant epitopes elicit protective CD8+ T cell responses or instead act as decoys to subvert immunity and allow pathogens to establish chronic infection is unknown. Here we show that anatomically distinct human granulomas contain clonally expanded CD8+ T cells with overlapping T cell receptor (TCR) repertoires. Similarly, the murine CD8+ T cell response against M. tuberculosis is dominated by TB10.44-11-specific T cells ...


Tonb Not Directly Related To Efflux Of Antibiotics In E. Coli, Amber Gombash May 2015

Tonb Not Directly Related To Efflux Of Antibiotics In E. Coli, Amber Gombash

Honors Projects

Studies in Pseudomonas aeruginosa have suggested that the TonB energy transduction system directly contributes to efflux-mediated antibiotic resistance, ostensibly by energizing one or more efflux systems. We have found ∆tonB strains of Escherichia coli to similarly be more sensitive to certain antibiotics relative to wild-type strains. To test the hypothesis that this enhanced sensitivity involved the energization of efflux systems, sensitivity patterns for a variety of antibiotics were evaluated using a set of strains differentially lacking genes encoding the Acr efflux system, the universal outer membrane efflux portal TolC, and TonB. No correlation was evident between the resistance phenotypes of ...


Thermal Inactivation Of Shiga Toxin-Producing Escherichia Coli In Foods, Malcond David Valladares May 2015

Thermal Inactivation Of Shiga Toxin-Producing Escherichia Coli In Foods, Malcond David Valladares

Doctoral Dissertations

Emerging non-O157 Shiga toxin-producing Escherichia coli (STEC) were recently added to the zero tolerance policy by the USDA-FSIS. Therefore, the precise characterization of their thermal inactivation kinetics in different foods and the effect of stress on thermal inactivation are needed. This research aimed at determining the heat inactivation kinetics of non-O157 and O157 STECs in buffer and model food matrices and the effects of DnaK levels on thermal resistance after acid and heat-shock. Thermal inactivation was carried out in either in 2-ml glass vials or nylon vacuum-sealed bags for buffer and food (spinach, ground-beef, turkey deli-meat, pasta) samples, respectively. Vials ...


Genetic Diversity, Population Structure, And Evolution Of Virulence In Toxoplasma Gondii, Elliot Keats Cullen Shwab May 2015

Genetic Diversity, Population Structure, And Evolution Of Virulence In Toxoplasma Gondii, Elliot Keats Cullen Shwab

Doctoral Dissertations

Toxoplasma gondii is among the most widespread eukaryotic pathogens known. It chronically infects approximately one third of the world’s human population and has been isolated from an extremely diverse array of globally distributed mammals and birds. Understanding the structure of the worldwide T. gondii population enhances our understanding of the factors that have shaped that structure and led to the proliferation of one of the most evolutionarily successful pathogens on Earth. Herein we collate genotypic data from global isolates, demonstrating that T. gondii possesses a unique population structure in which only a small number of genotypes dominate throughout the ...


Data From: Human And Murine Clonal Cd8+ T Cell Expansions Arise During Tuberculosis Because Of Tcr Selection, Claudio Nunes-Alves, Matthew G. Booty, Stephen Carpenter, Alissa C. Rothchild, Constance J. Martin, Danielle Desjardins, Katherine Steblenko, Henrik Kloverpris, Rajhmun Madansein, Duran Ramsuran, Alasdair Leslie, Margarida Correia-Neves, Samuel M. Behar Apr 2015

Data From: Human And Murine Clonal Cd8+ T Cell Expansions Arise During Tuberculosis Because Of Tcr Selection, Claudio Nunes-Alves, Matthew G. Booty, Stephen Carpenter, Alissa C. Rothchild, Constance J. Martin, Danielle Desjardins, Katherine Steblenko, Henrik Kloverpris, Rajhmun Madansein, Duran Ramsuran, Alasdair Leslie, Margarida Correia-Neves, Samuel M. Behar

MaPS Research Data

Manuscript abstract: The immune system can recognize virtually any antigen, yet T cell responses against several pathogens, including Mycobacterium tuberculosis, are restricted to a limited number of immunodominant epitopes. The host factors that affect immunodominance are incompletely understood. Whether immunodominant epitopes elicit protective CD8+ T cell responses or instead act as decoys to subvert immunity and allow pathogens to establish chronic infection is unknown. Here we show that anatomically distinct human granulomas contain clonally expanded CD8+ T cells with overlapping T cell receptor (TCR) repertoires. Similarly, the murine CD8+ T cell response against M. tuberculosis is dominated by TB10.44-11-specific ...