Microbiology Commons^™

Secreted Ns1 Aids In Dengue Virus Entry By Binding Heparan Sulfate, Morgan E. Schafer, Michael Dibiasio-White, Richard J. Kuhn

The Summer Undergraduate Research Fellowship (SURF) Symposium

A large portion of the world’s population lives in an area where they are at risk of contracting Dengue Virus (DENV). While infection with DENV can result in a wide range of clinical manifestations, from flu-like symptoms to hemorrhagic shock, vascular leakage, and even death, no treatments currently exist. Previous studies have shown that higher levels of viral non-structural protein 1 (NS1) in the blood of infected patients correlate with more severe disease. NS1 has been shown to play many roles in the viral lifecycle, but the mechanisms by which NS1 executes these functions are unknown. Preliminary data from our …

Finding Human Proteins That Bind To A Lassa Virus Protein, Maria Alejandra Pardo Ruge, Veronica J. Heintz, Douglas J. Lacount

The Summer Undergraduate Research Fellowship (SURF) Symposium

Viral hemorrhagic fevers are severe illnesses caused by many different viruses. Lassa Virus is one of these important pathogens in Western Africa, causing hemorrhagic fever and eventually death without early medical treatment. There is no vaccine and there is little information on host-pathogen interactions. Therefore, the interaction between viral proteins and host targets is useful to understand Lassa virus’s lifecycle and pathology, and to develop ways to prevent infection. In this project, we study the nucleoprotein of Lassa virus (NP), which has been reported to have anti-interferon (IFN) activity through elimination of double stranded RNA (dsRNA). These features could be …

Stormwater Capture Via Green Infrastructure In The Plaster Creek Watershed, Skyler Fish, Ben Johnson, Deanna Geelhoed, David P. Warners

Student Papers and Reports

No abstract provided.

Molecular Mechanisms Of Dna Replication Initiation In Hpvs With Genetic Variations Leading To Cellular Carcinogenesis, Gulden Yilmaz

Graduate School of Biomedical Sciences Theses and Dissertations

Human papillomaviruses are a vast family of double-stranded DNA viruses containing non-carcinogenic and carcinogenic types, whose crucial differences remain unknown, except for the difference in the frequency of DNA replication. The human papillomavirus (HPV) E2 protein regulates the initiation of viral DNA replication and transcription. Its recognition and binding to four 12 bp palindromic sequences in the viral origin is essential for its function. Little is known about the DNA binding mechanism of the E2 protein found in HPV types that have low risk for oncogenicity (low-risk) as well as the roles of various elements of the individual binding sites. …

Simple Method For Markerless Gene Deletion In Multidrug Resistant Acinetobacter Baumannii, Bindu Subhadra, Man Hwan Oh, Chul Hee Choi

Faculty Publications - Biological Sciences

No abstract provided.

Green Team-Urban Ecological Restoration, Aracely Eikenberry, Stephanie Praamsma, Gail Heffner, David P. Warners

Student Papers and Reports

No abstract provided.

Comprehensive Assessments Of The Genetic Determinants In Salmonella Typhimurium For Fitness Under Host Stressors: Oxidative Stress And Iron Restriction, Sardar Abdullah

Graduate Theses and Dissertations

Salmonella is an intracellular pathogen that infects a wide range of hosts. The infected host utilizes reactive oxygen species (ROS) and iron-restriction to eliminate the pathogen. We used proteogenomics to determine the candidate genes and proteins that have a role in resistance of S. Typhimurium to H2O2. For Tn-seq, a highly saturated Tn5 library was grown in vitro under either 2.5 (H2O2L) or 3.5 mM H2O2 (H2O2H). We identified two sets of overlapping genes that are required for resistance of S. Typhimurium to H2O2L and H2O2H, and the results were validated via phenotypic evaluation of 50 selected mutants. The enriched …

Advances In Developing Therapies To Combat Zika Virus: Current Knowledge And Future Perspectives, Ashok Munjal, Rekha Khandia, Kuldeep Dharma, Swati Sachan, Kumaragurubaran Karthik, Ruchi Tiwari, Yashpal S. Malik, Deepak Kumar, Raj K. Singh, Hafiz M. N. Iqbal, Sunil K. Joshi

Bioelectrics Publications

Zika virus (ZIKV) remained largely quiescent for nearly six decades after its first appearance in 1947. ZIKV reappeared after 2007, resulting in a declaration of an international “public health emergency” in 2016 by the World Health Organization (WHO). Until this time, ZIKV was considered to induce only mild illness, but it has now been established as the cause of severe clinical manifestations, including fetal anomalies, neurological problems, and autoimmune disorders. Infection during pregnancy can cause congenital brain abnormalities, including microcephaly and neurological degeneration, and in other cases, Guillain-Barré syndrome, making infections with ZIKV a substantial public health concern. Genomic and …

Peptide Inhibitors Targeting The Neisseria Gonorrhoeae Pivotal Anaerobic Respiration Factor Ania, Aleksandra E. Sikora, Robert H. Mills, Jacob V. Weber, Adel Hamza, Bryan W. Passow, Andrew Romaine, Zachary A. Williamson, Robert W. Reed, Ryszard A. Zielke, Konstantin V. Korotkov

Molecular and Cellular Biochemistry Faculty Publications

Neisseria gonorrhoeae causes the sexually transmitted infection gonorrhea, which is highly prevalent worldwide and has a major impact on reproductive and neonatal health. The superbug status of N. gonorrhoeae necessitates the development of drugs with different mechanisms of action. Here, we focused on targeting the nitrite reductase AniA, which is a pivotal component of N. gonorrhoeae anaerobic respiration and biofilm formation. Our studies showed that gonococci expressing AniA containing the altered catalytic residues D137A and H280A failed to grow under anaerobic conditions, demonstrating that the nitrite reductase function is essential. To facilitate the pharmacological targeting of AniA, new crystal structures …

Growth And Survivability Of Microorganisms At Martian Temperatures And Pressures, Rebecca Lynne Mickol

Graduate Theses and Dissertations

The discovery of methane in the martian atmosphere via numerous ground- and space-based sources has prompted the study of methanogens as models for life on Mars. Methanogens are microorganisms within the domain Archaea, many of which utilize carbon dioxide (CO2) and hydrogen to produce methane. The non-photosynthetic nature of methanogens indicates that they could exist in sub-surface environments, protected from harmful UV and ionizing radiation on the surface of Mars. These organisms also do not require organics, which are sparse on the planet.

Additionally, the wide variety of environments we find life in on Earth, as well as evidence for …

Characterization Of Porphyromonas Gingivalis Mfa1 Fimbriae., Jae Yong Lee

Electronic Theses and Dissertations

Porphyromonas gingivalis, an obligate anaerobic bacterium associated with chronic periodontitis, utilizes various virulence factors to achieve pathogenicity, one of which is the Mfa1 fimbriae. As a surface structure comprising Mfa1 major subunit along with accessory fimbrial proteins Mfa2-5, the Mfa1 fimbriae has been shown to mediate the adherence of P. gingivalis to antecedent bacterial colonizers of the oral cavity to cause increased virulence. However, the spatial relationships amongst the individual subunits and their assembly mechanism have remained unclear. Through immuno-electron microscopy, Mfa1-4 were localized on the surface of P. gingivalis with Mfa1 localizing throughout the fimbriae and Mfa2 in …

Porphyromonas Gingivalis Infection In Gestational Diabetes Mellitus And Survival In Tobacco Smokers., Himabindu Gogeneni

Electronic Theses and Dissertations

This thesis contains a clinical project and distinct basic science project. Gestational diabetes mellitus occurs in 4% of pregnancies and increases the risk of birth defects, pre-term birth, and miscarriage. Gingivitis during pregnancy also increases the risk for poor pregnancy outcome. Gingivitis is a bacterial-induced disease, and specific plaque pathogens have been associated with systemic sequelae to periodontal inflammation. Therefore, we set out to monitor oral infection with three key periodontopathogens (Porphyromonas gingivalis, Filifactor alocis, and Treponema denticola) and the systemic inflammatory burden [C-reactive protein (CRP) in pregnant women with and without gingivitis and gestational diabetes. Gingivitis …

Genetic Divergence Of Influenza A(H3n2) Amino Acid Substitutions Mark The Beginning Of The 2016-2017 Winter Season In Israel, Aharona Glatman-Freedman, Yaron Drori, Sharon Beni, Nehemya Friedman, Rakefet Pando, Hanna Sefty, Ilana Tal, John Mccauley, Galia Rahav, Nathan Keller, Tamy Shohat, Ella Mendelson, Musa Hindiyeh, Michal Mandelboim

NYMC Faculty Publications

BACKGROUND: Influenza vaccine composition is reevaluated each year due to the frequency and accumulation of genetic changes that influenza viruses undergo. The beginning of the 2016-2017 influenza surveillance period in Israel has been marked by the dominance of influenza A(H3N2).

OBJECTIVES: To evaluate the type, subtype, genetic evolution and amino acid substitutions of influenza A(H3N2) viruses detected among community patients with influenza-like illness (ILI) and hospitalized patients with respiratory illness in the first weeks of the 2016-2017 influenza season.

STUDY DESIGN: Respiratory samples from community patients with influenza-like illness and from hospitalized patients underwent identification, subtyping and molecular characterization. Hemagglutinin …

Persistence Of Enteric Viruses On Surfaces Under Varying Environmental Conditions, Nicole L. Turnage

Graduate Theses and Dissertations

Human enteric viruses such as human norovirus (hNoV) and Aichivirus A (AiV) are common foodborne viruses with hNoVs being identified as the leading causative agent of foodborne illnesses in the U.S. Moreover, hNoVs have been identified as the leading cause of nonbacterial acute gastroenteritis in the U.S. and worldwide. Fomite surface contamination is a major transmission route for enteric viruses. The application of an optimized virus recovery method from fomites is essential for better understanding of virus persistence under varying environmental conditions (EC). This study aimed to optimize a surface sampling method for virus recovery from nonporous food contact surfaces …

Genetic Tools To Allow Efficient Gene And Protein Characterization Of The Industrially Important Bacterium Gluconobacter Oxydans, Melissa A. Schoeben

Graduate Theses/Dissertations

The acetic acid bacterium Gluconobacter oxydans is an industrially valuable microorganism, particularly in the production of acetic acid, D-gluconic acid, ketogluconic acids, dihydroxyacetone, and precursors for the antidiabetic drug miglitol. Despite its importance in industry, there is still much to be learned about G. oxydans and its many uncharacterized enzymes. Additionally, genetic engineering holds the possibility of improving current yields. However, these goals are limited, largely due to a lack of molecular tools suitable for working with the bacterium. The current molecular toolkit for G. oxydans specifically lacks an efficient screening system for positive clones and a system for regulatable …

Functional Consequences Of Rna Exosome Complex Alteration By Conformational Changes And Cofactor Binding, Jaeil Han

Dissertations and Theses (Open Access)

The RNA exosome is an essential 3’-5 ribonuclease that processes or degrades a variety of RNA species in eukaryotes. It is composed of nine structural cores and one catalytic subunit, Rrp44. Structural studies captured two different conformations of Rrp44, Rrp44^ch (channel) and Rrp44^da (direct-access). The Rrp44^ch appears to recruit RNA substrates from the central channel formed by the core subunits, while the substrate is directly recruited to Rrp44^da bypassing the central channel. Although in vivo function of the Rrp44^ch-exosome is extensively studied, the function or even the presence of the Rrp44^da-exosome in …

Vorinostat Renders The Replication-Competent Latent Reservoir Of Human Immunodeficiency Virus (Hiv) Vulnerable To Clearance By Cd8 T Cells., Julia A Sung, Katherine Sholtis, Jennifer Kirchherr, Joann D Kuruc, Cynthia L Gay, Jeffrey L Nordstrom, Catherine M Bollard, Nancie M Archin, David M Margolis

Pediatrics Faculty Publications

Latently human immunodeficiency virus (HIV)-infected cells are transcriptionally quiescent and invisible to clearance by the immune system. To demonstrate that the latency reversing agent vorinostat (VOR) induces a window of vulnerability in the latent HIV reservoir, defined as the triggering of viral antigen production sufficient in quantity and duration to allow for recognition and clearance of persisting infection, we developed a latency clearance assay (LCA). The LCA is a quantitative viral outgrowth assay (QVOA) that includes the addition of immune effectors capable of clearing cells expressing viral antigen. Here we show a reduction in the recovery of replication-competent virus from …

Microbial Community Richness Distinguishes Shark Species Microbiomes In South Florida, Rachael Cassandra Karns

HCNSO Student Theses and Dissertations

The microbiome (microbial community) of individuals is crucial when characterizing and understanding processes that are required for organism function and survival. Microbial organisms, which make up an individual’s microbiome, can be linked to disease or function of the host organism. In humans, individuals differ substantially in their microbiome compositions in various areas of the body. The cause of much of the composition diversity is yet unexplained, however, it is speculated that habitat, diet, and early exposure to microbes could be altering the microbiomes of individuals (Human Microbiome Project Consortium, 2012b, 2012a). To date, only one study has reported on microbiome …

Cutaneous Microbial Community Variation Across Populations Of Eastern Hellbenders (Cryptobranchus Alleganiensis Alleganiensis), Obed Hernandez-Gomez, Jason T. Hoverman, Rod N. Williams

Natural Sciences and Mathematics | Faculty Scholarship

Multicellular hosts maintain complex associations with microbial communities. While microbial communities often serve important functional roles for their hosts, our understanding of the local and regional processes that structure these communities remains limited. Metacommunity analyses provide a promising tool for investigating mechanisms shaping microbiome heterogeneity, which is essential for predicting functional variation between hosts. Using a metacommunity framework, we examined heterogeneity in the skin microbiome of the eastern hellbender (Cryptobranchus alleganiensis alleganiensis). Hellbenders are broadly distributed throughout river systems in the eastern United States, but are present in specific environmental locations throughout their range. The large range of the species …

Bacterial Communities Associated With Healthy And Diseased Acropora Cervicornis (Staghorn Coral) Using High-Throughput Sequencing, Charles Walton

HCNSO Student Theses and Dissertations

Coral diseases were first noted in the 1960s and 1970s and have had major impacts globally on coral reef community structures. In the Caribbean, a major outbreak of white band disease has been considered responsible for the drastic decline of Caribbean Acroporids since the 1970s. In addition to white band disease, another more recently described condition known as rapid tissue loss (RTL) has had major impacts on Acropora cervicornis populations, specifically offshore Broward County Southeast Florida. While these diseases have contributed to the population decline, determining their etiologies has been elusive.

Coral diseases have been characterized by shifts in their …

The Feoabc Locus Of Yersinia Pestis Likely Has Two Promoters Causing Unique Iron Regulation, Lauren O'Connor, Jacqueline D. Fetherston, Robert D. Perry

Microbiology, Immunology, and Molecular Genetics Faculty Publications

The FeoABC ferrous transporter is a wide-spread bacterial system. While the feoABC locus is regulated by a number of factors in the bacteria studied, we have previously found that regulation of feoABC in Yersinia pestis appears to be unique. None of the non-iron responsive transcriptional regulators that control expression of feoABC in other bacteria do so in Y. pestis. Another unique factor is the iron and Fur regulation of the Y. pestis feoABC locus occurs during microaerobic but not aerobic growth. Here we show that this unique iron-regulation is not due to a unique aspect of the Y. pestis …

Tumor Necrosis Factor Dynamically Regulates The Mrna Stabilome In Rheumatoid Arthritis Fibroblast-Like Synoviocytes, Konstantinos Loupasakis, David Kuo, Upneet K. Sokhi, Christopher Sohn, Bethany Syracuse, Eugenia G. Giannopoulou, Sung Ho Park, Hyelim Kang, Gunnar Rätsch, Lionel B. Ivashkiv, George D. Kalliolias

Publications and Research

During rheumatoid arthritis (RA), Tumor Necrosis Factor (TNF) activates fibroblast-like synoviocytes (FLS) inducing in a temporal order a constellation of genes, which perpetuate synovial inflammation. Although the molecular mechanisms regulating TNF-induced transcription are well characterized, little is known about the impact of mRNA stability on gene expression and the impact of TNF on decay rates of mRNA transcripts in FLS. To address these issues we performed RNA sequencing and genome-wide analysis of the mRNA stabilome in RA FLS. We found that TNF induces a biphasic gene expression program: initially, the inducible transcriptome consists primarily of unstable transcripts but progressively switches …

Draft Genome Sequence Of Bacillus Altitudinis Ynp4-Tsu, Isolated From Yellowstone National Park, Joshua A. O'Hair, Hui Li, Santosh Thapa, Matthew Scholz, Suping Zhou

Agricultural and Environmental Sciences Faculty Research

Undisturbed hot springs inside Yellowstone National Park remain a dynamic biome for novel cellulolytic thermophiles. We report here the draft genome sequence of one of these isolates, Bacillus altitudinis YNP4-TSU.

How Science Makes America Great, Kenneth Nickerson

Kenneth Nickerson Papers

The proposed Federal Budget cuts funding for NIH, NSF, and CDC by 16% each and for the EPA by a whopping 31%. Ouch! The situation seems ironic because of President Trump’s slogan “Make America great again!”, which I agree with wholeheartedly. In addition to being a scientist, I also love history (especially military history) and science is at the top of my list of what has made the United States great. ... Why do we do it? I’m in science because it is rewarding. It is invigorating to discover how nature works. Scientists may act individually and in relative obscurity, …

Antimicrobial Hydroxyapatite-Gelatin-Silica Composite Pastes With Tunable Setting Properties, Vuk Uskoković, Shreya Ghosh, Victoria M. Wu

Pharmacy Faculty Articles and Research

Bone grafting is one of the commonest surgical procedures, yet all bone substitutes developed so far suffer from specific weaknesses and the search for a bone graft material with ideal physical and biological properties is still ongoing. Calcium phosphate pastes are the most frequently used synthetic bone grafts, yet they (a) often take an impractically long time to set, (b) release the drug content too fast, and (c) do not form pores large enough to accommodate host cells and foster osseointegration. To make up for these deficiencies, we introduced gelatin and silica to pastes composed of 5–15 nm sized hydroxyapatite …

Pseudogymnoascus Destructans Transcriptome Changes During White-Nose Syndrome Infections, Sophia M. Reeder, Jonathan M. Palmer, Jenni M. Prokkola, Thomas M. Lilley, Deeann M. Reeder, Ken Field

Faculty Journal Articles

White nose syndrome (WNS) is caused by the psychrophilic fungus Pseudogymnoascus destructans that can grow in the environment saprotrophically or parasitically by infecting hibernating bats. Infections are pathological in many species of North American bats, disrupting hibernation and causing mortality. To determine what fungal pathways are involved in infection of living tissue, we examined fungal gene expression using RNA-Seq. We compared P. destructans gene expression when grown in culture to that during infection of a North American bat species, Myotis lucifugus, that shows high WNS mortality. Cultured P. destructans was grown at 10 to 14 C and P. destructans …

An Integrated Bioinformatic/Experimental Approach For Discovering Novel Type Ii Polyketides Encoded In Actinobacterial Genomes, Wubin Gao

Chemistry and Chemical Biology ETDs

Discovery of new natural products (NPs) is critical both for diseases treatment and crops protection. Numerous NP biosynthetic gene clusters (BGCs) in sequenced microbial genomes allow identification of new NPs through genome mining. Developing an integrated bioinformatic/experimental approach for discovering novel type II polyketides (PK-IIs) facilitates investigation of this family of NPs in an efficient, systematic way. Here, we developed an approach to analyze ketosynthase α/β (KSα/β) gene sequences to predict PK-II core structures, allowing us to target novel PK-II BGCs either from isolated genomic DNA or genomes from the NCBI databank, and to isolate novel PK-IIs produced by these …

Intestinal Microbiota Diversity Of Pre-Smolt Steelhead (Oncorhynchus Mykiss) Across Six Oregon And Washington Hatcheries, Christina Carrell Yildirimer

Dissertations and Theses

The Pacific Northwest is known for its once-abundant wild salmonid populations that have been in decline for more than 50 years due to habitat destruction and commercial overexploitation. To compensate, federal and state agencies annually release hundreds of thousands of hatchery-reared fish into the wild. However, accumulating data indicate that hatchery fish have lower fitness in natural environments, and that hatchery rearing negatively influences return rates of anadromous salmonids. Recently, mounting evidence revealed that the richness and diversity of intestinal microbial species influence host health. We examined the gut microbiota of pre-migratory hatchery-reared steelhead (Oncorhynchus mykiss) to assess …

Osteopontin Facilitates West Nile Virus Neuroinvasion Via Neutrophil “Trojan Horse” Transport, Amber M. Paul, Dhiraj Acharya, Laurel Duty, E. Ashley Thompson, Linda Le, Dobrivoje S. Stokic, A. Arturo Leis, Fengwei Bai

Publications

West Nile virus (WNV) can cause severe human neurological diseases including encephalitis and meningitis. The mechanisms by which WNV enters the central nervous system (CNS) and host factors that are involved in WNV neuroinvasion are not completely understood. The proinflammatory chemokine osteopontin (OPN) is induced in multiple neuroinflammatory diseases and is responsible for leukocyte recruitment to sites of its expression. In this study, we found that WNV infection induced OPN expression in both human and mouse cells. Interestingly, WNV-infected OPN deficient (Opn−/−) mice exhibited a higher survival rate (70%) than wild type (WT) control mice (30%), suggesting OPN plays a …

Discovering Antibacterial And Anti-Resistance Agents Targeting Multi-Drug Resistant Eskape Pathogens, Renee Fleeman

USF Tampa Graduate Theses and Dissertations

Antibiotic resistance has been a developing problem for mankind in recent decades and multi-drug resistant bacteria are now encountered that are resistant to all treatment options available. In 2014, the World Health Organization announced that this problem is driving us towards a “post-antibiotic era” that will change the face of modern medicine as we know it. If lack of novel antibiotic development and FDA approval continues, by the year 2050, 10 million people will die each year to an antimicrobial resistant bacterial infection. With lack of pharmaceutical industry involvement in developing novel antibiotics, the responsibility now lies within the academic …