Microbiology Commons^™

Biosynthesis And Roles Of Virulence Conferring Cell Wall Associated Dimycocerosate Esters In Mycobacterium Marinum, Poornima Mohandas

Dissertations, Theses, and Capstone Projects

Mycobacterial species include a variety of obligate and opportunistic pathogens that cause several important diseases affecting mankind such as tuberculosis and leprosy. The most unique feature of these bacteria is their intricate cell wall that poses a permeability barrier to antibiotics and contributes to their pathogenicity and persistence within the host. The cell wall hosts several complex lipids such as dimycocerosate esters (DIMs), which are found in many clinically relevant pathogenic species of mycobacteria. DIMs have been implicated in the virulence of mycobacteria and play a major role in helping the bacteria evade host immune responses. It is therefore crucial …

Is Aerosalization A Problem With Carbapenem-Resistant Acinetobacter Baumannii In Thailand Hospital?, Anucha Apisarnthanarak, Ploenpit Tantajina, Pornpimol Laovachirasuwan, David J. Weber, Nalini Singh

Pediatrics Faculty Publications

We evaluated the presence of air contamination with carbapenem-resistant Acinetobacter baumannii (CRAB) in medical units where patients with CRAB pneumonia were hospitalized, and in Obstetrics and Gynecology units with open-air ventilation in-patient settings. There was no evidence of CRAB contamination in either of the units.

Household Clustering Of Escherichia Coli Sequence Type 131 Clinical And Fecal Isolates According To Whole Genome Sequence Analysis, James R. Johnson, Gregg Davis, Connie Clabots, Brian D. Johnston, Stephen Porter, Lance B. Price, +10 Additional Authors

Environmental and Occupational Health Faculty Publications

Background. Within-household sharing of strains from the resistance-associated H30R1 and H30Rx subclones of Escherichia coli sequence type 131 (ST131) has been inferred based on conventional typing data, but has been assessed minimally using whole genome sequence (WGS) analysis.

Methods. Thirty-three clinical and fecal isolates of ST131-H30R1 and ST131-H30Rx, from 20 humans and pets in six households, underwent WGS analysis for comparison with 52 published ST131 genomes. Phylogenetic relationships were inferred using a bootstrapped maximum likelihood tree based on core genome sequence polymorphisms. Accessory traits were compared between phylogenetically similar isolates.

Results. In the WGS-based …

The Influence Of Juncus-Rhizosphere Dissolved Organic Matter On Coastal Plankton Communities, Brittany Zepernick, Robert Michael Mckay, George S. Bullerjahn, Jeffrey W. Krause, Behzad Mortazavi

Honors Projects

Many aquatic plants produce copious amounts of dissolved organic matter (DOM) which enters surrounding waters and potentially stimulates planktonic activity. In the northern Gulf of Mexico, Juncus roemarianus (i.e. black needlerush) is a dominant marsh grass species residing in coastal zones and barrier islands. The below-ground biomass i.e. rhizosphere, can be consistently submerged, serving as a potential source of DOM to the surrounding waters. The lability and possible stimulatory effect of J. roemarianus DOM was examined for three plankton communities collected within the discharge region of Mobile Bay and adjacent waters of Gulf Shores, Alabama (less affected by Mobile Bay). …

A Pan-Dengue Virus Reverse Transcription-Insulated Isothermal Pcr Assay Intended For Point-Of-Need Diagnosis Of Dengue Virus Infection By Use Of The Pockit Nucleic Acid Analyzer, Yun Young Go, R. P. V. Jayanthe Rajapakse, Senanayake A. M. Kularatne, Pei-Yu Alison Lee, Keun Bon Ku, Sangwoo Nam, Pin-Hsing Chou, Yun-Long Tsai, Yu-Lun Liu, Hsiao-Fen Grace Chang, Hwa-Tang Thomas Wang, Udeni B. R. Balasuriya

Maxwell H. Gluck Equine Research Center Faculty Publications

Dengue virus (DENV) infection is considered a major public health problem in developing tropical countries where the virus is endemic and continues to cause major disease outbreaks every year. Here, we describe the development of a novel, inexpensive, and user-friendly diagnostic assay based on a reverse transcription-insulated isothermal PCR (RT-iiPCR) method for the detection of all four serotypes of DENV in clinical samples. The diagnostic performance of the newly established pan-DENV RT-iiPCR assay targeting a conserved 3′ untranslated region of the viral genome was evaluated. The limit of detection with a 95% confidence was estimated to be 10 copies of …

The Pmrhfijklm Operon In Yersinia Pseudotuberculosis Enhances Resistance To Ccl28 And Promotes Phagocytic Engulfment By Neutrophils, Lauren Elizabeth Johnson

Theses and Dissertations

Yersinia pseudotuberculosis is a foodborne pathogen that is the ancestral strain to Yersinia pestis, the causative agent of Plague. Y. pseudotuberculosis invades a host through the intestinal epithelium. The bacteria resist mucosal innate immune defenses including antimicrobial chemokines and phagocytic cells, and replicate in local lymph nodes. They cause Tuberculosis-like symptoms, including necrosis of local tissue and granuloma formation. Like all bacteria, Y. pseudotuberculosis has a net negative charge, which contributes to its susceptibility to some cationic antimicrobial peptides. Y. pseudotuberculosis is able to reduce this negative charge by adding 4-amino-4-deoxy-L-arabinose (L-Ara4N) to the lipid A portion of lipopolysaccharide. The …

Glomus Tumor Of Trachea In An Adult Male, Sidra Arshad, Zubair Ahmad, Nasir Ud Din

Department of Pathology and Laboratory Medicine

Glomus tumors most commonly occur in distal extremities, particularly in the subungual region. The origin of these tumors is modified smooth muscle cells of glomus bodies. Trachea is one of the rare sites where normal glomus bodies may be sparse or absent, so occurrence of glomus tumor in trachea is very rare. Only 30 cases have been reported in the literature so far. In this case report, the authors describe a very rare and in fact first case of glomus tumor of trachea in a 45-year male Pakistani patient.

Characterization Of Five Brevibacillus Bacteriophages And Their Genomes, Michael Allen Sheflo

Theses and Dissertations

Brevibacillus laterosporus (B. laterosporus) is a pathogen difficult to distinguish from Paenibacillus larvae (P. larvae), and contributes to Colony Collapse Disorder (CCD) of honeybees. To develop a biocontrol agent to limit its presence, bacteriophages were isolated from Utah County soil samples and used to infect B. laterosporus isolated from Utah County honey and larvae samples. Since CCD is prevalent in Utah beehives, bacteriophage that infect and lyse B. laterosporus may be isolated and characterized. Pathogens were isolated from soil samples, and 16S rRNA gene tests initially identified the strains as P. larvae. Bacteriophages were isolated, purified, and amplified sufficiently to …

Characterization Of Influenza Nucleoprotein Body Domain As Antiviral Target, Alicia Morgan Davis

Electronic Theses, Projects, and Dissertations

Influenza is a segmented negative strand RNA virus. Each RNA segment is encapsulated by viral nucleoprotein (NP) and bound by the viral RNA dependent RNA polymerase (RdRP) to form viral ribonucleoproteins (vRNPs) responsible for RNA synthesis. NP is a structural component of the vRNP but also interacts with both viral and host factors to regulate viral RNA expression. NP is conserved among influenza A isolates, making NP interactions compelling antiviral targets. Here I characterize mutations within 5 amino acids of NP that comprise an accessible region of the NP body domain, as determined by NP crystal structure. This region was …

The Role Of The Transcriptional Antiterminator Rfah In Lipopolysaccharide Synthesis, Resistance To Antimicrobial Peptides, And Virulence Of Yersinia Pseudotuberculosis And Yersinia Pestis, Jared Michael Hoffman

Theses and Dissertations

RfaH is a unique bacterial protein that enhances transcription of a select group of long operons in many Gram-negative bacteria. Operons regulated by RfaH possess an upstream operon polarity suppressor sequence, which recruits the RfaH protein to the RNA polymerase during transcription of genes, most of which are involved in the synthesis of cell-surface features. These include synthesis of the lipopolysaccharide (LPS) core and O-antigen in Salmonella and Escherichia coli, as well as F-plasmid conjugation pilus and capsule in E. coli. LPS is an important virulence factor in many Gram-negative bacteria, and protects Y. pseudotuberculosis against host antimicrobial …

The Effects Of Quorum Sensing And Temperature On The Soluble Proteome Of Vibrio Salmonicida, Christopher L. Massey

Master's Theses

Vibrio salmonicida causes cold-water vibriosis in salmon populations around the world and causes financial damage to fisheries designed to farm these salmon. Very little is known about the physiology of how V. salmonicida causes disease and measures to contain vibriosis are restricted to either vaccinating individual fish against disease or administering antibiotics when an outbreak is detected. These procedures are costly and increase the risk for selection of antibiotic-resistant V. salmonicida strains. A recent reoccurrence of outbreaks in Norwegian fisheries provided incentive to better understand the virulence mechanisms of V. salmonicida. In this thesis, a proteomic approach was used to …

Human Herpesvirus 6a Infection And Immunopathogenesis In Humanized Rag2-/-Γc-/- Mice And Relevance To Hiv/Aids And Autoimmunity, Anne Tanner

Theses and Dissertations

Human herpesvirus 6A (HHV-6A) has yet to be definitively linked to a specific disease. This is due in part to the ubiquitous nature of the virus. Humanized Rag2^-/-γc-/- (Rag-hu) mice were tested to determine if these were a suitable animal model to study the virus. Both cell-free and cell-associated virus was used for infection and both were found to be efficient at infecting the mice. Viral DNA was found in the plasma and cellular blood fractions, bone marrow, lymph node, and thymus, indicating successful infection and propagation of the virus in vivo. The CD3+CD4- population was depleted, while the …

Comparative Studies Of Tslp And Il-7 In Normal Early Human Neonatal And Adult B Cell Development, Terry-Ann Milford

Loma Linda University Electronic Theses, Dissertations & Projects

Defining the role of cytokines in promoting human B cell development is important for understanding B cell leukemia and for developing strategies to restore B cell production that is lost during some therapies. The purpose of this study was to investigate the roles of the IL-7R ligands, thymic stromal lymphopoietin (TSLP) and IL- 7, in the early stages of normal postnatal and adult human B cell development. Using novel in vitro and in vivo model systems, we show that TSLP and IL-7 are able to expand B cell precursors individually and in combination from CB hematopoietic stem cells. In this …

The Exceptionally High Reactivity Of Cys 621 Is Critical For Electrophilic Activation Of The Sensory Nerve Ion Channel Trpa1, Parmvir K. Bahia, Thomas A. Parks, Katherine R. Stanford, David A. Mitchell, Sameer Varma, Stanley M. Stevens Jr., Thomas E. Taylor-Clark

Molecular Biosciences Faculty Publications

Activation of the sensory nerve ion channel TRPA1 by electrophiles is the key mechanism that initiates nociceptive signaling, and leads to defensive reflexes and avoidance behaviors, during oxidative stress in mammals. TRPA1 is rapidly activated by subtoxic levels of electrophiles, but it is unclear how TRPA1 outcompetes cellular antioxidants that protect cytosolic proteins from electrophiles. Here, using physiologically relevant exposures, we demonstrate that electrophiles react with cysteine residues on mammalian TRPA1 at rates that exceed the reactivity of typical cysteines by 6,000-fold and that also exceed the reactivity of antioxidant enzymes. We show that TRPA1 possesses a complex reactive cysteine …

The Frequency Of Influenza And Bacterial Co-Infection: A Systematic Review And Meta-Analysis., Eili Y. Klein, Bradley Monteforte, Alisha Gupta, Wendi Jiang, Larissa May, Yu-Hsiang Hsieh, Andrea Freyer Dugas

Emergency Medicine Faculty Publications

AIM: Co-infecting bacterial pathogens are a major cause of morbidity and mortality in influenza. However, there remains a paucity of literature on the magnitude of co-infection in influenza patients.

METHOD: A systematic search of MeSH, Cochrane Library, Web of Science, SCOPUS, EMBASE, and PubMed was performed. Studies of humans in which all individuals had laboratory confirmed influenza, and all individuals were tested for an array of common bacterial species, met inclusion criteria.

RESULTS: Twenty-seven studies including 3,215 participants met all inclusion criteria. Common etiologies were defined from a subset of eight articles. There was high heterogeneity in the results (I(2) …

Glycosphingolipid Gm3 Is Indispensable For Dengue Virus Genome Replication, Kezhen Wang, Gang Bian, Tingting Feng, Penghua Wang, Yunsen Li, Jianfeng Dai

NYMC Faculty Publications

Dengue virus (DENV) causes the most prevalent arthropod-borne viral disease of humans worldwide. Glycosphingolipids (GSLs) are involved in virus infection by regulating various steps of viral-host interaction. However, the distinct role of GSLs during DENV infection remains unclear. In this study, we used mouse melanoma B16 cells and their GSL-deficient mutant counterpart GM95 cells to study the influence of GSLs on DENV infection. Surprisingly, GM95 cells were highly resistant to DENV infection compared with B16 cells. Pretreatment of B16 cells with synthetase inhibitor of GM3, the most abundant GSLs in B16 cells, or silencing GM3 synthetase T3GAL5, significantly inhibited DENV …

Mathematical Models Of Biofilm For Antimicrobial Persistence, Jia Zhao

Biology and Medicine Through Mathematics Conference

No abstract provided.

Needle In The Haystack: Combining Intravital Imaging And Mathematical Modeling To Understand How Vaccine-Induced T Cells Find Malaria-Infected Cells In Murine Livers, Vitaly V. Ganusov, Ian Cockburn, Reka Kelemen

Biology and Medicine Through Mathematics Conference

No abstract provided.

Hiv Vaccines: Progress, Limitations And A Crispr/Cas9 Vaccine, Omar A. Garcia Martinez

Biology: Student Scholarship & Creative Works

ABSTRACT: The HIV-1 pandemic continues to thrive due to ineffective HIV-1 vaccines. Historically, the world’s most infectious diseases, such as polio and smallpox, have been eradicated or have come close to eradication due to the advent of effective vaccines. Highly active antiretroviral therapy is able to delay the onset of AIDS but can neither rid the body of HIV-1 proviral DNA nor prevent further transmission. A prophylactic vaccine that prevents the various mechanisms HIV-1 has to evade and attack our immune system is needed to end the HIV-1 pandemic. Recent advances in engineered nuclease systems, like the CRISPR/Cas9 system, have …

Characterization Of The Marine Sponge Amphimedon Compressa Microbiome Across A Spatial Gradient, Renee Michelle Potens

HCNSO Student Theses and Dissertations

Diverse and ecologically important microbial communities (microbiomes) are symbiotic within marine sponges. In this study, the microbiome of Amphimedon compressa from three sample locations (Broward and Dade Counties, Southeast Florida, USA and the Southern Caribbean, Bocas del Toro, Panama) is characterized using 16S rRNA Illumina sequencing. The predominant taxa are Proteobacteria and Cyanobacteria, as expected for Low Microbial Abundance sponges, accounting for over 53% of the total microbiome community. The numbers of Operational Taxonomic Units (OTUs) decrease from Broward County (2,900) to Dade County (2,300) and then Bocas del Toro (1,200). The correlates to a decreasing north-south gradient of …

Phylogenetic Analysis Of Human Cytomegalovirus Pus27 And Pus28: Ascertaining An Independent Or Linked Evolutionary History, Jessica A. Scarborough

Undergraduate Honors Theses

Human cytomegalovirus (HCMV) is a widespread pathogen that is particularly skilled at evading immune detection and defense mechanisms, largely due to extensive co-evolution with its host’s immune system. One aspect of this co-evolution involves the acquisition of four virally encoded GPCR chemokine receptor homologs, products of the US27, US28, UL33 and UL78 genes. G protein-coupled receptors (GPCR) are the largest family of cell surface proteins, found in organisms from yeast to humans. In this research, phylogenetic analysis was used to investigate the origins of the US27 and US28 genes, which are adjacent in the viral genome. The results indicate that …

Water Quality And Fecal Coliform Levels In Georgia Oxbow Lakes Relative To Connectivity With The Savannah River, Carly B. Williams, John E. Weinstein, Claudia L. Rocha

Georgia Journal of Science

The state of Georgia has many bodies of water that provide important wildlife habitats as well as recreational opportunities. The objective of the current study was to investigate water quality and fecal coliform levels in oxbow lakes relative to their connectivity to the Savannah River. For most water quality parameters, no differences were observed between the Savannah River and the oxbow lakes. However, pH and turbidity values were lower in the oxbow lakes (both connected and disconnected) relative to the Savannah River. Fecal coliform values between connected oxbow lakes and the Savannah River were similar to each other and significantly …

Characterization Of A Mitochondrial Localizing Molluscum Contagiosum Virus Protein: Mc163r, Jesse Coutu

Seton Hall University Dissertations and Theses (ETDs)

Molluscum Contagiosum Virus (MCV) is an obligate human, tumorigenic poxvirus which causes benign skin neoplasms. Reduced inflammation during an MCV infection has been attributed to production of MCV immune evasion molecules (IEMs). IEMs antagonize host immune responses allowing MCV to evade the host immune system and reprogram the host cell for viral growth. MCV IEMs alter apoptosis (MC159, MC160), deregulate the cell cycle targeting retinoblastoma (MC007), and produce a chemokine homolog (MC148). Bioinformatics analysis identified MC163, as another potential host-interacting protein. Further analysis of MC163 resulted in the identification of a mitochondrial localization sequence, putative superoxide dismutase (SOD)-like Cu^{2+ …}

Flow Cytometric Analysis For Cyanobacteria In 36 New Jersey Freshwater Bodies, Ruchit Patel

Seton Hall University Dissertations and Theses (ETDs)

Eutrophication, a process that occurs due to excessive accumulation of nutrients such as nitrogen and phosphorous is primarily from anthropogenic nitrogen and natural occurrences. This phenomenon causes cyanobacterial overgrowth which can potentially lead to toxic algal blooms that affect public drinking water sources and recreational usage. An immediate need to detect bloom forming cyanobacteria in freshwater bodies early hand is critical to implement prevention strategies. These microorganisms contain phycobiliproteins such as phycoerytrhin, and allophycocyanin as part of the phycobillisome that allow autofluorescence. In this study, 36 freshwater bodies from 14 New Jersey counties were collected and processed for flow cytometric …

Modified Green Tea Polyphenol, Palmitoyl-Egcg And Black Tea Theaflavins: Promising Natural Herpes Simplex Virus 1 And 2 Agents, Aline Moraes De Oliveira

Seton Hall University Dissertations and Theses (ETDs)

Green tea and black tea originate from the leaves of Camellia Sinensis plant and contain antioxidants known to possess antiviral properties, including anti-HSV (Herpes Simplex Virus). There is no cure for the diseases caused by HSV infections. While there is a rising concern over the increase in resistant HSV strains, new effective agents for prevention are in critical need to be developed. Green tea’s polyphenol epigallocatechin gallate (EGCG), and its modification palmitoyl-EGCG (p-EGCG), along with black tea theaflavins TF1, TF2, TF3 have been used to study their antiviral effect against HSV type 1 (HSV-1) and HSV type 2 (HSV-2). These …

Handwashing: A Study Of The History, Methods, And Psychology Surrounding Hand Hygiene, Daniel J. Remillard

Senior Honors Theses

This paper covers three different areas concerning handwashing. First a review of the history of handwashing is done, going from ancient times to its introduction into modern medicine via Dr. Ignaz Semmelweis. This section gives a sobering reminder not to instantly reject data that comes in conflict with prevalent thought.

Then current medical knowledge about handwashing is examined, and the conclusion reached states that handwashing is best done with non-antibacterial soap.

Finally, a review of the psychology of handwashing shows that medical professionals often tend toward neglect if unwatched and unmotivated by an outside source. However, those suffering from obsessive …

Isolation And Enumeration Of Vibrio Vulnificus And Vibrio Parahaemolyticus From Coastal Virginia, Zackary A. Zayakosky

Senior Honors Projects, 2010-2019

Vibrio vulnificus and V. parahaemolyticus are gram-negative, halophilic bacteria that are found throughout estuarial waters during the summer months, and are commonly associated with human infection. Gastroenteritis and other related symptoms can occur following infection from either organism, which most often occurs as a result of consumption of raw oysters or other seafood. V. vulnificus is particularly virulent, and can also produce wound infections that lead to severe septicemia and death. Due to the increasing rates of infection for these two organisms, recent research efforts have focused on potential environmental conditions and reservoirs that would be indicative of increased Vibrio …

Regulation Of Cid-Mediated Cell Death In Staphylococcus Aureus, Ian H. Windham

Theses & Dissertations

The death and lysis of a subpopulation of cells in Staphylococcus aureus biofilms is thought to benefit the surviving population by releasing extracellular DNA, a critical component of the biofilm extracellular matrix. Although the means by which S. aureus controls cell death and lysis is not completely understood, studies implicate the role of the cidABC, alsSD and lrgAB operons in this process. This dissertation has focused on the regulation of cidABC and alsSD expression, which is mediated, primarily, by the LysR-Type Transcriptional Regulator (LTTR) known as CidR. To better define the role of CidR in regulating cidABC and alsSD transcription …

Role Of Stemloop D In Terminally Deleted Coxsackievirus B3 Replication, Lee K. Jaramillo

Theses & Dissertations

Coxsackievirus B3 (CVB3) is an enterovirus with no known form of latency. However, assays designed to detect enteroviral RNA have shown that CVB3 RNA can persist for weeks beyond the acute infection both naturally and experimentally. Our previous work with coxsackievirus revealed an inhibited version of enteroviral replication where the progeny virus, termed terminally deleted (TD) virus, was missing a maximum of 49 nucleotides from the beginning of the 5’ non-translated region (NTR). The largest terminally deleted virus, TD50, effaced stem a, stemloop b, and stemloop c from the secondary structure, the cloverleaf. We hypothesized that further deletion beyond those …

Spatiotemporal Control Of Staphylococcus Aureus Biofilm Development, Derek E. Moormeier

Theses & Dissertations

Chronic biofilm-related infections caused by the human pathogen Staphylococcus aureus often lead to significant increases in morbidity and mortality in both hospital- and community-associated settings. Typically, S. aureus biofilm development occurs in three stages: 1) attachment, 2) tower maturation, and 3) dispersal. Here, utilizing BioFlux1000 time-lapse microscopy we have expanded upon these fundamental stages of biofilm development and also unveiled and characterized two additional stages (multiplication and exodus).

The attachment and multiplication stages were shown to be protease sensitive but independent of most cell surface-associated proteins. Following multiplication, an exodus of the biofilm population that followed the transition of the …