Microbiology Commons^™

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 …

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 …

Complete Denitrification By The Non-Denitrifier Anaeromyxobacter Dehalogenans: The Role Of Coupled Biotic-Abiotic Reactions, Jenny Rae Onley

Doctoral Dissertations

Nitrous oxide (N₂O) is a potent greenhouse gas and ozone-depleting substance produced by many different pathways in the nitrogen cycle, including nitrification, denitrification, and chemodenitrification. Abiotic sources of N₂O such as the chemical reaction between nitrite (NO₂^-) and ferrous ion (Fe[II]) are generally neglected in studies of N turnover in soils. Abiotic controls containing nitrate (NO₃^-) and ferric iron (Fe[III]) fail to capture potential reactions between intermediates of N cycle pathways (e.g., NO₂^- as an intermediate in NO₃ - reduction to ammonium [NH₄⁺] or …

Detection, Diversity, And Evolution Of Fungal Nitric Oxide Reductases (P450nor), Steven Adam Higgins

Doctoral Dissertations

Nitrous oxide (N₂O) is a gas responsible for significant ozone layer depletion and contributes to greenhouse effects in Earth’s atmosphere. N₂O is primarily generated by denitrification, whereby nitrate (NO_3-) or nitrite (NO_2-) is converted to gaseous N₂O or N2. Teragram quantities of N₂O are emitted annually from agricultural soils treated with nitrogenous fertilizers due to the activity of soil microbiota. Although bacteria and fungi harbor genes permitting denitrification, fungi lack NosZ, an enzyme responsible for reducing N₂O into inert N2 gas. Historically, scientists have linked fungi …

Managing Exoelectrogenic Microbial Community Development Through Bioprocess Control For Conversion Of Biomass-Derived Streams, Alex James Lewis

Doctoral Dissertations

Bioelectrochemical systems are an emerging technology capable of utilizing aqueous waste streams generated during biomass conversion of lignocellulosic feedstocks to produce valuable co-products and thus, have potential to be integrated into biorefineries. In a microbial electrolysis cell, organic compounds are converted to electrons, protons, and CO₂ by fermentative and exoelectrogenic bacteria in the anode compartment. By having the ability to extract electrons from waste streams, these systems can treat water while also producing hydrogen, and thus can improve the efficiency of biomass to fuel production by minimizing external hydrogen requirement and enabling water recycle. The overall goal of this …

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 …

An Inducible Fluorescent Reporter System To Measure Lux Operon Promoter Activity, Nicole Thunes

Theses and Dissertations

Bioluminescence is the enzymatic production of light by a living organism. Many species of marine bacteria produce light with varying degrees of brightness. The lux operon is responsible for bioluminescence and is well studied, however it is currently unknown why different species of bacteria display different brightness levels. A dual-plasmid system designed to mimic the quorum-sensing induction of the lux operon was created and successfully implemented in E. coli. This was accomplished through the use of an arabinose-inducible plasmid containing a luxR gene from Vibrio harveyi, and then using the resulting LuxR protein to activate the lux promoter in a …

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 …

New Insights Into The Role Of Antimicrobials Of Xenorhabdus In Interspecies Competition, Kristin Jean Ciezki

Theses and Dissertations

Xenorhabdus spp. are symbionts of entomopathogenic nematodes and pathogens of susceptible insects. The nematodes penetrate the insect midgut to enter the hemocoel where Xenorhabdus bacteria are released, transitioning to their pathogenic stage. During nematode invasion microbes from the insect gut translocate into the hemocoel. In addition, different species of nematodes carrying specific strains of Xenorhabdus can invade a single insect. Xenorhabdus spp thereby engage in competition with both related strains and nonrelated gut microbes. In complex media Xenorhabdus spp produce diverse antimicrobial compounds whose functions in biological systems remain poorly understood. R-type bacteriocins are contractile phage-tail-like structures that are bactericidal …

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 …

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 …

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. …

Expression Profiling Of Non-Coding Rna By Environmental Interactions In Innate Immunity, Jacob R. Longfellow

Electronic Theses and Dissertations

Cystic fibrosis (CF) is a genetic disorder that affects 30,000 people in the United States and currently has no cure. Although CF affects all of the body’s systems, it is largely characterized as a lung disease. CF is caused by a mutation in both copies of the gene for cystic fibrosis transmembrane conductance regulator (CFTR). A mutation in the CFTR gene leads to improper movement of chloride ions and water into the airways, which dysregulates the airway surface liquid volume and composition. Individuals with CF are prone to lung infections due to inefficient bacterial clearance and by the age of …

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 …

The Role Of Pilj And Its Structural Domains In The Localization And Function Of The Chp Chemosensory System In Pseudomonas Aeruginosa, Vibhuti Hemantkumar Jansari

Theses and Dissertations

Bacteria detect environmental signals using membrane-bound methyl-accepting chemotaxis proteins (MCPs), which are part of a larger complex of chemosensory proteins. Pseudomonas aeruginosa has four functionally distinct chemosensory protein complexes. The Chp chemosensory system regulates type IV pili mediated twitching motility and intracellular levels of cAMP by modulating the activity of an adenylate cyclase, CyaB. The Chp system is also proposed to be involved in type IV pili mediated directional twitching motility towards phosphatidylethanolamine (PE). PilJ is the only MCP predicted to be associated with the Chp system. In this study we investigated different domains of PilJ in order to decipher …

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 …

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

MSU Graduate Theses

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 …

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 …

Mitochondrial Regulation Of Yeast Ampk During Energy Stress, Aishwarya Shevade

Theses and Dissertations

In eukaryotes, members of the conserved AMP-activated protein kinase (AMPK) family play a pivotal role in sensing and responding to energy stress. Mammalian AMPK becomes activated when the AMP:ATP ratio is too high, and functions to prevent unnecessary ATP spending and to increase ATP production. Due to their role in ATP production through aerobic respiration, mitochondria are known to play an indirect role in the negative control of AMPK. The conserved voltage-dependent anion channel (VDAC) proteins, also known as mitochondrial porins, mediate the passage of small metabolites between the mitochondria and cytoplasm, including the release of ATP. One would therefore …