Organisms Commons^™

Zinc Transporters Ybtx And Znuabc Are Required For The Virulence Of Yersinia Pestis In Bubonic And Pneumonic Plague In Mice, Alexander G. Bobrov, Olga Kirillina, Marina Y. Fosso, Jacqueline D. Fetherston, M. Clarke Miller, Tiva T. Vancleave, Joseph A. Burlison, William K. Arnold, Matthew B. Lawrenz, Sylvie Garneau-Tsodikova, Robert D. Perry

Microbiology, Immunology, and Molecular Genetics Faculty Publications

A number of bacterial pathogens require the ZnuABC Zinc (Zn²⁺) transporter and/or a second Zn²⁺ transport system to overcome Zn²⁺ sequestration by mammalian hosts. Previously we have shown that in addition to ZnuABC, Yersinia pestis possesses a second Zn²⁺ transporter that involves components of the yersiniabactin (Ybt), siderophore-dependent iron transport system. Synthesis of the Ybt siderophore and YbtX, a member of the major facilitator superfamily, are both critical components of the second Zn²⁺ transport system. Here we demonstrate that a ybtX znu double mutant is essentially avirulent in mouse models of bubonic and pneumonic …

Lymphoid Hematopoiesis And The Role Of B-Cells In Transgenic Mouse Model Of Sickle Cell Disease, Christina Cotte

University Scholar Projects

Sickle cell disease (SCD) has been shown to be associated with decreased baseline immunity and thus increased susceptibility to infection. I sought to discern possible causes of this by looking into the correlations between SCD and hematopoiesis, the immune system and the neuroendocrine system, and ultimately by conducting experiments surrounding the impaired immune system of SCD. These experiments focused on the potential causes and effects of the diminution of B-1a cells in the SCD spleen. Adoptive transfers, infections with Streptococcus pneumoniae, and histologic imaging were conducted to establish if the diminution of the B-1a cells in the SCD spleen …

Identification Of Intrahelical Bifurcated H‑Bonds As A New Type Of Gate In K+ Channels, Oliver Rauh, Martin Urban, Leonhard M. Henkes, Tobias Winterstein, Timo Greiner, James L. Van Etten, Anna Moroni, Stefan M. Kast, Gerhard Thiel, Indra Schroeder

James Van Etten Publications

Gating of ion channels is based on structural transitions between open and closed states. To uncover the chemical basis of individual gates, we performed a comparative experimental and computational analysis between two K⁺ channels, Kcv_S and Kcv_NTS. These small viral encoded K+ channel proteins, with a monomer size of only 82 amino acids, resemble the pore module of all complex K+ channels in terms of structure and function. Even though both proteins share about 90% amino acid sequence identity, they exhibit different open probabilities with ca. 90% in Kcv_NTS and 40% in Kcv_S. …

Are Cdi Systems Multicolored, Facultative, Helping Greenbeards?, Elizabeth S. Danka, Erin C. Garcia, Peggy A. Cotter

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Competitive and cooperative interactions between organisms, including bacteria, can significantly impact the composition of a community and the fitness of its members, as well as the fitness of their hosts when communities are living on or within other organisms. Understanding the underlying mechanisms is critical to the development of strategies to control microbiological communities that impact animal and plant health and also for understanding the evolution of social behaviors, which has been challenging for evolutionary biologists. Contact-dependent growth inhibition (CDI) is a phenomenon defined by the delivery of a protein toxin to the cytoplasm of neighboring bacteria upon cell–cell contact, …

Chat Expression In Chlamydia Muridarum-Infected Female Murine Genital Tract, Hallie Sartain

Undergraduate Honors Theses

Chlamydia trachomatis is the most prevalent agent of bacterial sexually transmitted infections in the world. However, a profuse number of cases are unreported, as the infection is often asymptomatic. Sequelae such as pelvic inflammatory disease, an increased risk of cervical cancer, premature birth, and perinatal infections in pregnant women can occur. Inflammation occurs in the body in response to infection or injury. Although inflammation can lead to some unwanted secondary effects, such as pain, it serves to return the body to homeostasis by restoring injured tissues and eliminating pathogens. One recently identified connection between the central nervous system and the …

Determination Of The Effects That A Previously Uncharacterized Secreted Product From Klebsiella Pneumoniae Has On Citrobacter Freundii And Enterobacter Cloacae Biofilms, Cody M. Hastings

Undergraduate Honors Theses

More so than ever, Multiple Drug Resistant (MDR) bacteria are on the rise due to overuse of antibiotics along with natural selection for adaptations that enhance drug-resistant properties. One particular bacterial family, Enterobacteriaceae, has been problematic, exhibiting several bacterial members that have developed a precipitous resistance to modern antibiotics and are also primary causative agents of nosocomial, or hospital acquired, infections. Citrobacter freundii (CF) and Enterobacter cloacae (ECL) are two species of the Enterobacteriaceae family causing significant medical concern due to their role in producing numerous opportunistic infections such as bacteremia, lower respiratory tract infections, urinary tract infections, and endocarditis. …

Range-Wide Prevalence And Impacts Of Pseudocercosporella Inconspicua On Lilium Grayi And An Assessment Of L. Superbum And L. Michauxii As Reservoirs, Cindy L. Barrett

Electronic Theses and Dissertations

Lilium grayi (Gray’s Lily), a southern Appalachian endemic species, is threatened by a Lilium-specific fungal pathogen, Pseudocercosporella inconspicua. The disease is characterized by tan lesions that can cause early senescence, while also lowering seed production and viability. This project tested for P. inconspicua conidia and accessed health at nine locations. The disease was present and ubiquitous across the range of L. grayi. Through identification of P. inconspicua conidia in the field, L. superbum (Turk’s Cap Lily) was identified as an additional host, while L. michauxii (Michaux’s Lily) was disease-free. However, infection was inducible in both species. With …

Pharmacodynamic Activity Of Fosfomycin Simulating Urinary Concentrations Achieved After A Single 3 Gram Oral Dose Versus Escherichia Coli Using An In Vitro Model, George G. Zhanel, Kate Parkinson, Sean Higgins, Andrew Denisuik, Heather Adam, Johann Pitout, Ayman Noreddin, James A. Karlowsky

Pharmacy Faculty Articles and Research

We assessed the activity of fosfomycin simulating urinary concentrations achieved after a single 3 gram oral dose against Escherichia coli using an in vitro pharmacodynamic model. Eleven urinary isolates of E. coli were studied. Isolates were ESBL-producing or carbapenemase-producing. The in vitro pharmacodynamic model was inoculated with an inoculum of (~1 × 10⁶ cfu/mL). Fosfomycin was administered to simulate maximum free (ƒ) urine (U) concentrations and a t_1/2 obtained after a standard single 3 gram oral dose in healthy volunteers (ƒU_max, 4000 mg/L; t_1/2, 6 h). Sampling was performed over 48 h to assess …

The Effects Of A Hpv Educational Intervention Aimed At Collegiate Males On Knowledge, Vaccine Intention, And Uptake, Mary A. Knudtson

Evidence-Based Practice Project Reports

Human Papillomavirus (HPV) is the most common sexually transmitted infection (STI) in the United States (US). In 2013, approximately 6% of 19 to 26-year-old males had received at least one dose of the HPV vaccine (Richman, Maddy, Torres, & Goldberg, 2016). Currently there is no known cure for HPV, however a prophylactic vaccination provides an efficacious method for protection against HPV related diseases. The purpose of the evidence-based project was to provide a HPV educational intervention to collegiate males and examine the effects of HPV knowledge, intention to vaccinate, and receipt of vaccination. The Health Belief Model was selected to …

Granting Personhood For Sentient Non-Human Animals And Sentient Artificial Intelligences: A Demonstrative Argument, Jeremiah Meadows

Virginias Collegiate Honors Council Conference

While the subject of personhood has been exhaustively debated regarding the unborn, personhood for sentient animals and artificial intelligences is a concept that is rarely deliberated. Humanity has learned that there are multiple animal species which are very similar to humans in their self-awareness, emotional capacity, and free will. These traits have been partially developed for artificial intelligences as well, and those characteristics will evolve alongside human and technological development. As stratified societies emerged, there have been multiple occurrences where individuals were deemed lesser but then later acquired equal standing. Dr. Daniel Wilson, roboticist, wrote in his novel Robopocalypse, “It …

Thujone Inhibits The Function Of Α7-Nicotinic Acetylcholine Receptors And Impairs Nicotine-Induced Memory Enhancement In One-Trial Passive Avoidance Paradigm, Ahmed Sultan, Keun-Hang Susan Yang, Dmytro Isaev, Eslam El Nebrisi, Nurulain Syed, Nadia Khan, Christopher F. Howarth, Bassem Sadek, Murat Oz

Mathematics, Physics, and Computer Science Faculty Articles and Research

Effects of thujone, a major ingredient of absinthe, wormwood oil and some herbal medicines, were tested on the function of α7 subunit of the human nicotinic acetylcholine (α7 nACh) receptor expressed in Xenopus oocytes using the two-electrode voltage-clamp technique. Thujone reversibly inhibited ACh (100 μM)-induced currents with an IC50 value of 24.7 μM. The effect of thujone was not dependent on the membrane potential and did not involve Ca2+-dependent Cl- channels expressed endogenously in oocytes. Inhibition by thujone was not reversed by increasing ACh concentrations. Moreover, specific binding of [125I] -bungarotoxin was not altered by thujone. Further experiments in SH-EP1 …

Targeted Aav5-Smad7 Gene Therapy Inhibits Corneal Scarring In Vivo, Suneel Gupta, Jason T. Rodier, Ajay Sharma, Elizabeth A. Giuliano, Prashant R. Sinha, Nathan P. Hesemann, Arkasubhra Ghosh, Rajiv R. Mohan

Pharmacy Faculty Articles and Research

Corneal scarring is due to aberrant activity of the transforming growth factor β (TGFβ) signaling pathway following traumatic, mechanical, infectious, or surgical injury. Altered TGFβ signaling cascade leads to downstream Smad (Suppressor of mothers against decapentaplegic) protein-mediated signaling events that regulate expression of extracellular matrix and myogenic proteins. These events lead to transdifferentiation of keratocytes into myofibroblasts through fibroblasts and often results in permanent corneal scarring. Hence, therapeutic targets that reduce transdifferentiation of fibroblasts into myofibroblasts may provide a clinically relevant approach to treat corneal fibrosis and improve long-term visual outcomes. Smad7 protein regulates the functional effects of TGFβ signaling …

Virus-Mediated Suppression Of Host Non-Self Recognition Facilitates Horizontal Transmission Of Heterologous Viruses, Songsong Wu, Jiasen Cheng, Yanping Fu, Tao Chen, Daohong Jiang, Said A. Ghabrial, Jiatao Xie

Plant Pathology Faculty Publications

Non-self recognition is a common phenomenon among organisms; it often leads to innate immunity to prevent the invasion of parasites and maintain the genetic polymorphism of organisms. Fungal vegetative incompatibility is a type of non-self recognition which often induces programmed cell death (PCD) and restricts the spread of molecular parasites. It is not clearly known whether virus infection could attenuate non-self recognition among host individuals to facilitate its spread. Here, we report that a hypovirulence-associated mycoreovirus, named Sclerotinia sclerotiorum mycoreovirus 4 (SsMYRV4), could suppress host non-self recognition and facilitate horizontal transmission of heterologous viruses. We found that cell death in …

Draft Genome Sequence Of Cercospora Sojina Isolate S9, A Fungus Causing Frogeye Leaf Spot (Fls) Disease Of Soybean, Fanchang Zeng, Chaofan Wang, Guirong Zhang, Junmei Wei, Carl A. Bradley, Ray Ming

Plant Pathology Faculty Publications

Fungi are the causal agents of many of the world's most serious plant diseases causing disastrous consequences for large-scale agricultural production. Pathogenicity genomic basis is complex in fungi as multicellular eukaryotic pathogens. The fungus Cercospora sojina is a plant pathogen that threatens global soybean supplies. Here, we report the genome sequence of C. sojina strain S9 and detect genome features and predicted genomic elements. The genome sequence of C. sojina is a valuable resource with potential in studying the fungal pathogenicity and soybean host resistance to frogeye leaf spot (FLS), which is caused by C. sojina. …

Photosynthetic Bacterium Rhodopseudomonas Palustris Gj-22 Induces Systemic Resistance Against Viruses, Pin Su, Xinqiu Tan, Chenggang Li, Deyong Zhang, Ju’E Cheng, Songbai Zhang, Xuguo Zhou, Qingpin Yan, Jing Peng, Zhuo Zhang, Yong Liu, Xiangyang Lu

Entomology Faculty Publications

Photosynthetic bacteria (PSB) have been extensively used in agriculture to promote plant growth and to improve crop quality. Their potential application in plant disease management, however, is largely overlooked. In this study, the PSB strain Rhodopseudomonas palustris GJ-22 was investigated for its ability to induce resistance against a plant virus while promoting plant growth. In the field, a foliar spray of GJ-22 suspension protected tobacco plants against tobacco mosaic virus (TMV). Under axenic conditions, GJ-22 colonized the plant phyllosphere and induced resistance against TMV. Additionally, GJ-22 produced two phytohormones, indole-3-acetic acid and 5-aminolevulinic acid, which promote growth and germination in …

Mice With Infectious Colitis Exhibit Linear Growth Failure And Subsequent Catch-Up Growth Related To Systemic Inflammation And Igf-1, Mark D. Deboer, Vidhya Vijayakumar, Meiqing Gong, John L. Fowlkes, Rachel M. Smith, Fernando Ruiz-Perez, James P. Nataro

Barnstable Brown Diabetes Center Faculty Publications

In developing communities, intestinal infection is associated with poor weight gain and linear-growth failure. Prior translational animal models have focused on weight gain investigations into key contributors to linear growth failure have been lacking. We hypothesized that murine intestinal infection with Citrobacter-rodentium would induce linear-growth failure associated with systemic inflammation and suppressed serum levels of insulin-like growth factor-1 (IGF-1). We evaluated 4 groups of mice infected or sham-infected on day-of-life 28: uninfected-controls, wild-type C.-rodentium-infected, partially-attenuated C. rodentium-infected (with deletion of 3 serine protease genes involved in colonization), and pair-fed (given the amount of daily food consumed by the …

Hendra Virus Fusion Protein Transmembrane Domain Contributes To Pre-Fusion Protein Stability, Stacy Webb, Tamas Nagy, Hunter Moseley, Michael G. Fried, Rebecca Ellis Dutch

Molecular and Cellular Biochemistry Faculty Publications

Enveloped viruses utilize fusion (F) proteins studding the surface of the virus to facilitate membrane fusion with a target cell membrane. Fusion of the viral envelope with a cellular membrane is required for release of viral genomic material, so the virus can ultimately reproduce and spread. To drive fusion, the F protein undergoes an irreversible conformational change, transitioning from a metastable pre-fusion conformation to a more thermodynamically stable post-fusion structure. Understanding the elements that control stability of the pre-fusion state and triggering to the post-fusion conformation is important for understanding F protein function. Mutations in F protein transmembrane (TM) domains …

Osteoblast-Derived Fgf9 Regulates Skeletal Homeostasis, Liping Wang, Theresa M. Roth, Marcia J. Abbott, Linh Ho, Lalita Wattanachanya, Robert A. Nissenson

Health Sciences and Kinesiology Faculty Articles

FGF9 has complex and important roles in skeletal development and repair. We have previously observed that Fgf9 expression in osteoblasts (OBs) is regulated by G protein signaling and therefore the present study was done to determine whether OB-derived FGF9 was important in skeletal homeostasis. To directly test this idea, we deleted functional expression of Fgf9 gene in OBs using a 2.3 kb collagen type I promoter-driven Cre transgenic mouse line (Fgf9^{OB −/−}). Both Fgf9 knockout (Fgf9^{OB −/−}) and the Fgf9 floxed littermates (Fgf9^fl/fl) mice were fully backcrossed and maintained in an FBV/N background. Three …

Freshwater Fungal Infections, Dennis J. Baumgardner

Journal of Patient-Centered Research and Reviews

Fungal infections as a result of freshwater exposure or trauma are fortunately rare. Etiologic agents are varied, but commonly include filamentous fungi and Candida. This narrative review describes various sources of potential freshwater fungal exposure and the diseases that may result, including fungal keratitis, acute otitis externa and tinea pedis, as well as rare deep soft tissue or bone infections and pulmonary or central nervous system infections following traumatic freshwater exposure during natural disasters or near-drowning episodes. Fungal etiology should be suspected in appropriate scenarios when bacterial cultures or molecular tests are normal or when the infection worsens or …

A Comparative Genomic Analysis Of Putative Pathogenicity Genes In The Host-Specific Sibling Species Colletotrichum Graminicola And Colletotrichum Sublineola, Ester A. S. Buiate, Katia Viana Xavier, Neil Moore, Maria F. Torres, Mark L. Farman, Christopher L. Schardl, Lisa J. Vaillancourt

Plant Pathology Faculty Publications

Background: Colletotrichum graminicola and C. sublineola cause anthracnose leaf and stalk diseases of maize and sorghum, respectively. In spite of their close evolutionary relationship, the two species are completely host-specific. Host specificity is often attributed to pathogen virulence factors, including specialized secondary metabolites (SSM), and small-secreted protein (SSP) effectors. Genes relevant to these categories were manually annotated in two co-occurring, contemporaneous strains of C. graminicola and C. sublineola. A comparative genomic and phylogenetic analysis was performed to address the evolutionary relationships among these and other divergent gene families in the two strains.

Results: Inoculation of maize with C. sublineola …