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Articles 61 - 90 of 118

Full-Text Articles in Organisms

Estudios En Biodiversidad, Volumen I, Griselda Pulido-Flores, Scott Monks, Maritza López-Herrera Nov 2015

Estudios En Biodiversidad, Volumen I, Griselda Pulido-Flores, Scott Monks, Maritza López-Herrera

Zea E-Books Collection

Este libro es el producto del trabajo colegiado que han desarrollado los profesores, investigadores, y estudiantes que conforman la Red Temática de Calidad Ambiental y Desarrollo Sustentable, a través del macroproyecto “Evaluación del impacto ambiental por actividades antropogénicas: Alternativas de mitigación”. El cual fue apoyado con recursos financieros por parte del Programa para el Desarrollo Profesional Docente (PRODEP), de la Secretaria de Educación Pública (SEP) en México. Las instituciones de educación superior y cuerpos participantes en la red temática son la Universidad Autónoma del Estado de Hidalgo (Uso, Manejo y Conservación de la Biodiversidad UAEHCA- 10; Ciencias Ambientales UAEH-CA-59); Universidad …


Detection Methods And Intestinal Adherence Of Non-O157 Shiga Toxin-Producing Escherichia Coli, Zachary R. Stromberg Nov 2015

Detection Methods And Intestinal Adherence Of Non-O157 Shiga Toxin-Producing Escherichia Coli, Zachary R. Stromberg

School of Veterinary and Biomedical Sciences: Dissertations, Theses, and Student Research

Shiga toxin-producing Escherichia coli (STEC) are enteric pathogens of humans. Cattle serve as a reservoir and harbor STEC in their intestines. Intimin-positive STEC are referred to as enterohemorrhagic E.coli (EHEC). Seven serogroups (O26, O45, O103, O111, O121, O145, and O157) account for the majority of illness due to STEC and are hereafter referred to as STEC/EHEC-7. To improve detection, enrichment broths were compared for supporting growth of STEC-7 and STEC O104:H4 (STEC-8). In pure culture, STEC enriched in trypticase soy broth (TSB) had significantly greater growth compared to TSB containing antimicrobials. In fecal samples, E. coli broth enrichment yielded …


Secretion Of Heat-Labile Enterotoxin By Porcine-Origin Enterotoxigenic Escherichia Coli And Relation To Virulence, Prageeth Rukshan Wijemanne Jun 2015

Secretion Of Heat-Labile Enterotoxin By Porcine-Origin Enterotoxigenic Escherichia Coli And Relation To Virulence, Prageeth Rukshan Wijemanne

School of Veterinary and Biomedical Sciences: Dissertations, Theses, and Student Research

Heat-labile enterotoxin (LT) is an important virulence factor secreted by some strains of porcine-origin enterotoxigenic Escherichia coli (pETEC). The prototypic human-origin strain H10407 secretes LT via a type II secretion system (T2SS), but its presence or importance in pETEC has not been established. Exposure of pETEC to glucose has been shown to result in different secretion levels of LT. Furthermore, the relationship between the level of LT secreted and the virulence potential of the respective pETEC strain has not been established. To determine the relationship between the capacity to secrete LT and virulence in wild-type (WT) pETEC, 16 strains isolated …


Characterization And Investigation Of Fungi Inhabiting The Gastrointestinal Tract Of Healthy And Diseased Humans, Mallory J. Suhr May 2015

Characterization And Investigation Of Fungi Inhabiting The Gastrointestinal Tract Of Healthy And Diseased Humans, Mallory J. Suhr

Department of Food Science and Technology: Dissertations, Theses, and Student Research

Gastrointestinal microbiome studies have failed to include fungi in total community analyses. As a result, their diversity and function in the gut is poorly understood. Recent work has begun to uncover the role intestinal fungi play in diet, immune system development, interactions with other microorganisms in the gut, and pathogenesis of diseases. Advances in sequencing technologies allow for the ability to profile the fungal gut microbiome (“mycobiome”) in healthy and diseased states. This thesis explores the mycobiome in 1) healthy humans with a vegetarian diet and 2) pediatric small bowel transplant recipients that develop fungal bloodstream infections.

The gut mycobiome …


Engineering Of A Light-Gated Potassium Channel, Christian Cosentino, Laura Alberio, Sabrina Gazzarrini, Marco Aquila, Eduardo Romano, Solei Cermenati, Paolo Zuccolini, Jan Petersen, Monica Beltrame, James L. Van Etten, John M. Christie, Gerhard Thiel, Anna Moroni Apr 2015

Engineering Of A Light-Gated Potassium Channel, Christian Cosentino, Laura Alberio, Sabrina Gazzarrini, Marco Aquila, Eduardo Romano, Solei Cermenati, Paolo Zuccolini, Jan Petersen, Monica Beltrame, James L. Van Etten, John M. Christie, Gerhard Thiel, Anna Moroni

James Van Etten Publications

The present palette of opsin-based optogenetic tools lacks a light-gated potassium (K+) channel desirable for silencing of excitable cells. Here, we describe the construction of a blue-light–induced K+ channel 1 (BLINK1) engineered by fusing the plant LOV2-Ja photosensory module to the small viral K+ channel Kcv. BLINK1 exhibits biophysical features of Kcv, including K+ selectivity and high single-channel conductance, but reversibly photoactivates in blue light. Opening of BLINK1 channels hyperpolarizes the cell to the K+ equilibrium potential. Ectopic expression of BLINK1 reversibly inhibits the escape response in light-exposed zebrafish larvae. BLINK1 therefore provides a single-component optogenetic tool that can establish …


Reply To Kjartansdóttir Et Al.: Chlorovirus Atcv-1 Findings Not Explained By Contamination, Robert H. Yolken, Lorraine Jones-Brando, David Dunigan, Geetha Kannan, Faith Dickerson, Emily Severance, Sarven Sabunciyan, C. Conover Talbot Jr., Emese Prandovszky, James Gurnon, Irina Agarkova, Flora Leister, Kristin L. Gressitt, Ou Chen, Bryan Deuber, Fangrui Ma, Mikhail V. Pletnikov, James L. Van Etten Mar 2015

Reply To Kjartansdóttir Et Al.: Chlorovirus Atcv-1 Findings Not Explained By Contamination, Robert H. Yolken, Lorraine Jones-Brando, David Dunigan, Geetha Kannan, Faith Dickerson, Emily Severance, Sarven Sabunciyan, C. Conover Talbot Jr., Emese Prandovszky, James Gurnon, Irina Agarkova, Flora Leister, Kristin L. Gressitt, Ou Chen, Bryan Deuber, Fangrui Ma, Mikhail V. Pletnikov, James L. Van Etten

James Van Etten Publications

We agree with Kjartansdóttir et al. (1) that extreme caution must be used when interpreting high-throughput sequencing results in new hosts. The situation demands thorough investigation and validation beyond the identification of a few sequencing reads. However, we believe it is unlikely that random laboratory contamination explains the results reported in Yolken et al. (2) for the following reasons. ...

Therefore, the conclusions in our report are based not only on “a few sequence reads” (1), but on confirmatory assays, as well as a highly controlled animal model of oral exposure and subsequent measurement of immune response and behavior. We …


Large Dsdna Chloroviruses Encode Diverse Membrane Transport Proteins, Gerhard Thiel, Timo Greiner, David Dunigan, Anna Moroni Jan 2015

Large Dsdna Chloroviruses Encode Diverse Membrane Transport Proteins, Gerhard Thiel, Timo Greiner, David Dunigan, Anna Moroni

James Van Etten Publications

Many large DNA viruses that infect certain isolates of chlorella-like green algae (chloroviruses) are unusual because they often encode a diverse set of membrane transport proteins, including functional K+ channels and aquaglyceroporins as well as K+ transporters and calcium transporting ATPases. Some chloroviruses also encode putative ligand-gated-like channel proteins. No one protein is present in all of the chloroviruses that have been sequenced, but the K+ channel is the most common as only two chloroviruses have been isolated that lack this complete protein. This review describes the properties of these membrane-transporting proteins and suggests possible physiological functions and evolutionary histories …


Chlorovirus Atcv-1 Is Part Of The Human Oropharyngeal Virome And Is Associated With Changes In Cognitive Functions In Humans And Mice, Robert H. Yolken, Lorraine Jones-Brando, David D. Dunigan, Geetha Kannan, Faith Dickerson, Emily Severance, Sarven Sabunciyan, C. Conover Talbot Jr., Emese Prandovszky, James R. Gurnon, Irina V. Agarkova, Flora Leister, Kristin L. Gressitt, Ou Chen, Bryan Deuber, Fangrui Ma, Mikhail V. Pletnikov, James L. Van Etten Nov 2014

Chlorovirus Atcv-1 Is Part Of The Human Oropharyngeal Virome And Is Associated With Changes In Cognitive Functions In Humans And Mice, Robert H. Yolken, Lorraine Jones-Brando, David D. Dunigan, Geetha Kannan, Faith Dickerson, Emily Severance, Sarven Sabunciyan, C. Conover Talbot Jr., Emese Prandovszky, James R. Gurnon, Irina V. Agarkova, Flora Leister, Kristin L. Gressitt, Ou Chen, Bryan Deuber, Fangrui Ma, Mikhail V. Pletnikov, James L. Van Etten

James Van Etten Publications

Chloroviruses (family Phycodnaviridae) are large DNA viruses known to infect certain eukaryotic green algae and have not been previously shown to infect humans or to be part of the human virome. We unexpectedly found sequences homologous to the chlorovirus Acanthocystis turfacea chlorella virus 1 (ATCV-1) in a metagenomic analysis of DNA extracted from human oropharyngeal samples. These samples were obtained by throat swabs of adults without a psychiatric disorder or serious physical illness who were participating in a study that included measures of cognitive functioning. The presence of ATCV-1 DNA was confirmed by quantitative PCR with ATCV-1 DNA being …


Chlorovirus Skp1-Binding Ankyrin Repeat Protein Interplay And Mimicry Of Cellular Ubiquitin Ligase Machinery, Eric A. Noel, Ming Kang, Jiri Adamec, James L. Van Etten, George A. Oyler Sep 2014

Chlorovirus Skp1-Binding Ankyrin Repeat Protein Interplay And Mimicry Of Cellular Ubiquitin Ligase Machinery, Eric A. Noel, Ming Kang, Jiri Adamec, James L. Van Etten, George A. Oyler

James Van Etten Publications

The ubiquitin-proteasome system is targeted by many viruses that have evolved strategies to redirect host ubiquitination machinery. Members of the genus Chlorovirus are proposed to share an ancestral lineage with a broader group of related viruses, nucleo-cytoplasmic large DNA viruses (NCLDV). Chloroviruses encode an Skp1 homolog and ankyrin repeat (ANK) proteins. Several chlorovirus-encoded ANK repeats contain C-terminal domains characteristic of cellular F-boxes or related NCLDV chordopox PRANC (pox protein repeats of ankyrin at C-terminal) domains. These observations suggested that this unique combination of Skp1 and ANK repeat proteins might form complexes analogous to the cellular Skp1-Cul1-F-box (SCF) ubiquitin ligase complex. …


Chlorovirus Pbcv-1 Encodes An Active Copper-Zinc Superoxide Dismutase, Ming Kang, Garry A. Duncan, Charles Kuszynski, George Oyler, Jiayin Zheng, Donald F. Becker, James L. Van Etten Aug 2014

Chlorovirus Pbcv-1 Encodes An Active Copper-Zinc Superoxide Dismutase, Ming Kang, Garry A. Duncan, Charles Kuszynski, George Oyler, Jiayin Zheng, Donald F. Becker, James L. Van Etten

James Van Etten Publications

Superoxide dismutases (SODs) are metalloproteins that protect organisms from toxic reactive oxygen species by catalyzing the conversion of superoxide anion to hydrogen peroxide and molecular oxygen. Chlorovirus PBCV-1 encodes a 187-amino-acid protein that resembles a Cu-Zn SOD with all of the conserved amino acid residues for binding copper and zinc (named cvSOD). cvSOD has an internal Met that results in a 165-amino-acid protein (named tcvSOD). Both cvSOD and tcvSOD recombinant proteins inhibited nitroblue tetrazolium reduction of superoxide anion generated in a xanthine-xanthine oxidase system in solution. tcvSOD was chosen for further characterization because it was easier to produce. Recombinant tcvSOD …


Expression Of Chlorovirus Mt325 Aquaglyceroporin (Aqpv1) In Tobacco And Its Role In Mitigating Drought Stress, Saadia Bihmidine, Mingxia Cao, Ming Kang, Tala Awada, James L. Van Etten, David Dunigan, Thomas E. Clemente Jul 2014

Expression Of Chlorovirus Mt325 Aquaglyceroporin (Aqpv1) In Tobacco And Its Role In Mitigating Drought Stress, Saadia Bihmidine, Mingxia Cao, Ming Kang, Tala Awada, James L. Van Etten, David Dunigan, Thomas E. Clemente

James Van Etten Publications

Main conclusions A Chlorovirus aquaglyceroporin expressed in tobacco is localized to the plastid and plasma membranes. Transgenic events display improved response to water deficit. Necrosis in adult stage plants is observed.

Aquaglyceroporins are a subclass of the water channel aquaporin proteins (AQPs) that transport glycerol along with other small molecules transcellular in addition to water. In the studies communicated herein, we analyzed the expression of the aquaglyceroporin gene designated, aqpv1, from Chlorovirus MT325, in tobacco (Nicotiana tabacum), along with phenotypic changes induced by aqpv1 expression in planta. Interestingly, aqpv1 expression under control of either a constitutive or …


Viruses As Nanoparticles: Structure Versus Collective Dynamics, S. Sirotkin, A. Mermet, M. Bergoin, V. Ward, James L. Van Etten Jan 2014

Viruses As Nanoparticles: Structure Versus Collective Dynamics, S. Sirotkin, A. Mermet, M. Bergoin, V. Ward, James L. Van Etten

James Van Etten Publications

In order to test the application of the “nanoparticle” concept to viruses in terms of low-frequency dynamics, large viruses (140–190 nm) were compared to similar-sized polymer colloids using ultra-small-angle x-ray scattering and very-low-frequency Raman or Brillouin scattering. While both viruses and polymer colloids show comparable highly defined morphologies, with comparable abilities of forming self-assembled structures, their respective abilities to confine detectable acoustic vibrations, as expected for such monodisperse systems, differed. Possible reasons for these different behaviors are discussed.


Viruses Infecting Marine Picoplancton Encode Functional Potassium Ion Channels, Fenja Siotto, Corinna Martin, Oliver Rauh, James L. Van Etten, Indra Schroeder, Anna Moroni, Gerhard Thiel Jan 2014

Viruses Infecting Marine Picoplancton Encode Functional Potassium Ion Channels, Fenja Siotto, Corinna Martin, Oliver Rauh, James L. Van Etten, Indra Schroeder, Anna Moroni, Gerhard Thiel

James Van Etten Publications

Phycodnaviruses are dsDNA viruses, which infect algae. Their large genomes encode many gene products, like small K+ channels, with homologs in prokaryotes and eukaryotes. Screening for K+ channels revealed their abundance in viruses from fresh-water habitats. Recent sequencing of viruses from marine algae or from salt water in Antarctica revealed sequences with the predicted characteristics of K+ channels but with some unexpected features. Two genes encode either 78 or 79 amino acid proteins, which are the smallest known K+ channels. Also of interest is an unusual sequence in the canonical α-helixes in K+ channels. Structural prediction algorithms indicate that the …


A Prospective Study Of Periodontal Disease And Risk Of Gastric And Duodenal Ulcer In Male Health Professionals, Matthew R. Boylan, Hamed Khalili, Edward S. Huang, Dominique S. Michaud, Jacques Izard, Kaumudi J. Joshipura, Andrew T. Chan Jan 2014

A Prospective Study Of Periodontal Disease And Risk Of Gastric And Duodenal Ulcer In Male Health Professionals, Matthew R. Boylan, Hamed Khalili, Edward S. Huang, Dominique S. Michaud, Jacques Izard, Kaumudi J. Joshipura, Andrew T. Chan

Department of Food Science and Technology: Faculty Publications

Periodontal disease is characterized by microbial shifts within the oral cavity and chronic inflammation of the gingival tissue, and can lead to tooth loss. Several studies support an association between periodontal disease and risk of chronic systemic conditions, including vascular disease, chronic obstructive pulmonary disease, diabetes mellitus, and cancer, including gastric adenocarcinoma. These associations may be mediated by systemic inflammation, the immune response to periodontal infection, or direct invasion by pathogens. Previous studies of periodontal disease and risk of peptic ulcer have been limited by cross-sectional design, diagnoses that were not confirmed by medical record review, and a lack of …


The Epidemiology Of Human Herpesvirus-8: Transmission Of Infection To Children In Zambian Households, Kay L. Crabtree Jul 2013

The Epidemiology Of Human Herpesvirus-8: Transmission Of Infection To Children In Zambian Households, Kay L. Crabtree

School of Biological Sciences: Dissertations, Theses, and Student Research

Human Herpes virus-8 (HHV-8) is the known etiologic agent for several malignant pathologies, including Kaposi’s sarcoma (KS), the most common tumor in children in sub-Saharan Africa. Saliva is implicated as the culprit of transmission; however there is a paucity of information regarding transmission to young children. In this study, we investigated the hypothesis that household behaviors exposing the susceptible child to saliva increase the risk of transmission of HHV-8 to that child.

To test our hypothesis a large prospective cohort study in Lusaka, Zambia, enrolling 464 young children and their households, was followed for 48 months. Socio-demographics, health histories, feeding …


Maternal Obesity Alters Fetal Development Due To Impaired Placental Function And Has Lasting Effects On Adult Offspring, Kristin Ann Norwood May 2013

Maternal Obesity Alters Fetal Development Due To Impaired Placental Function And Has Lasting Effects On Adult Offspring, Kristin Ann Norwood

Department of Animal Science: Dissertations, Theses, and Student Research

Obesity is an epidemic in many developed nations and maternal obesity can result in developmental alterations in offspring that have long-lasting effects. Two experiments were conducted to determine the impact of maternal obesity on placental development and early embryonic growth and muscle development. Experiment one utilized obese Lethal Yellow (LY) and normal weight C57BL/6 (B6) dams to assess how maternal obesity alters skeletal muscle development in mid-gestational embryos. Embryos from LY dams exhibited decreased embryo and placental weights as well as an increase in the myogenic marker desmin. Furthermore, the adipogenic marker PPARG expression was predominately localized to the neural …


The Voltage-Sensing Domain Of A Phosphatase Gates The Pore Of A Potassium Channel, Cristina Arrigoni, Indra Schroeder, Giulia Romani, James L. Van Etten, Gerhard Thiel, Anna Moroni Feb 2013

The Voltage-Sensing Domain Of A Phosphatase Gates The Pore Of A Potassium Channel, Cristina Arrigoni, Indra Schroeder, Giulia Romani, James L. Van Etten, Gerhard Thiel, Anna Moroni

James Van Etten Publications

The modular architecture of voltage-gated K+ (Kv) channels suggests that they resulted from the fusion of a voltage-sensing domain (VSD) to a pore module. Here, we show that the VSD of Ciona intestinalis phosphatase (Ci-VSP) fused to the viral channel Kcv creates KvSynth1, a functional voltage-gated, outwardly rectifying K+ channel. KvSynth1 displays the summed features of its individual components: pore properties of Kcv (selectivity and filter gating) and voltage dependence of Ci-VSP (V1/2 = +56 mV; z of approx. 1), including the depolarizationinduced mode shift. The degree of outward rectification of the channel is critically …


A Virus-Encoded Potassium Ion Channel Is A Structural Protein In The Chlorovirus Paramecium Bursaria Chlorella Virus 1 Virion, Giulia Romani, Adrianna Piotrowski, Stefan Hillmer, James Gurnon, James L. Van Etten, Anna Moroni, Gerhard Thiel, Brigitte Hertel Jan 2013

A Virus-Encoded Potassium Ion Channel Is A Structural Protein In The Chlorovirus Paramecium Bursaria Chlorella Virus 1 Virion, Giulia Romani, Adrianna Piotrowski, Stefan Hillmer, James Gurnon, James L. Van Etten, Anna Moroni, Gerhard Thiel, Brigitte Hertel

James Van Etten Publications

Most chloroviruses encode small K+ channels, which are functional in electrophysiological assays. The experimental finding that initial steps in viral infection exhibit the same sensitivity to channel inhibitors as the viral K+ channels has led to the hypothesis that the channels are structural proteins located in the internal membrane of the virus particles. This hypothesis was questioned recently because proteomic studies failed to detect the channel protein in virions of the prototype chlorovirus Paramecium bursaria chlorella virus 1 (PBCV-1). Here, we used a mAb raised against the functional K+ channel from chlorovirus MA-1D to search for the viral K+ channel …


A Virus-Encoded Potassium Ion Channel Is A Structural Protein In The Chlorovirus Paramecium Bursaria Chlorella Virus 1 Virion, Giulia Romani, Adrianna Piotrowski, Stefan Hillmer, James Gurnon, James L. Van Etten, Anna Morani, Gerhard Thiel, Brigitte Hertel Jan 2013

A Virus-Encoded Potassium Ion Channel Is A Structural Protein In The Chlorovirus Paramecium Bursaria Chlorella Virus 1 Virion, Giulia Romani, Adrianna Piotrowski, Stefan Hillmer, James Gurnon, James L. Van Etten, Anna Morani, Gerhard Thiel, Brigitte Hertel

James Van Etten Publications

Most chloroviruses encode small K+ channels, which are functional in electrophysiological assays. The experimental finding that initial steps in viral infection exhibit the same sensitivity to channel inhibitors as the viral K+ channels has led to the hypothesis that the channels are structural proteins located in the internal membrane of the virus particles. This hypothesis was questioned recently because proteomic studies failed to detect the channel protein in virions of the prototype chlorovirus Paramecium bursaria chlorella virus 1 (PBCV-1). Here, we used a mAb raised against the functional K+ channel from chlorovirus MA-1D to search for the viral K+ channel …


Potassium Ion Channels: Could They Have Evolved From Viruses?1[W], Gerhard Thiel, Anna Moroni, Guillaume Blanc, James L. Van Etten Jan 2013

Potassium Ion Channels: Could They Have Evolved From Viruses?1[W], Gerhard Thiel, Anna Moroni, Guillaume Blanc, James L. Van Etten

James Van Etten Publications

Cells communicate among themselves by electrical activity. Sophisticated membrane-embedded proteins, called ion channels, catalyze rapid, selective, and regulated ion fluxes across membranes (Hille, 2001). The resulting membrane currents are responsible for neuronal activity and the systemic propagation of electrical signals in animals. The activity of some channels is important for muscle movement in animals or growth in plants; other channels sense the concentration of physiological signals and modulate key processes in all kinds of eukaryotic cells. Among the many diverse ion channels in higher organisms, K+ channels are among the most important. One feature of K+ channels is that they …


Composition Of The Adult Digestive Tract Bacterial Microbiome Based On Seven Mouth Surfaces, Tonsils, Throat And Stool Samples, Nicola Segata, Susan Kinder Haake, Peter Mannon, Katherine P. Lemon, Levi Waldron, Dirk Gevers, Curtis Huttenhower, Jacques Izard Jun 2012

Composition Of The Adult Digestive Tract Bacterial Microbiome Based On Seven Mouth Surfaces, Tonsils, Throat And Stool Samples, Nicola Segata, Susan Kinder Haake, Peter Mannon, Katherine P. Lemon, Levi Waldron, Dirk Gevers, Curtis Huttenhower, Jacques Izard

Department of Food Science and Technology: Faculty Publications

Background: To understand the relationship between our bacterial microbiome and health, it is essential to define the microbiome in the absence of disease. The digestive tract includes diverse habitats and hosts the human body’s greatest bacterial density. We describe the bacterial community composition of ten digestive tract sites from more than 200 normal adults enrolled in the Human Microbiome Project, and metagenomically determined metabolic potentials of four representative sites.

Results: The microbiota of these diverse habitats formed four groups based on similar community compositions: buccal mucosa, keratinized gingiva, hard palate; saliva, tongue, tonsils, throat; sub- and supra-gingival plaques; …


Cell-Mediated Immunity In Porcine Reproductive And Respiratory Syndrome Virus, Rajeshwari Parida May 2012

Cell-Mediated Immunity In Porcine Reproductive And Respiratory Syndrome Virus, Rajeshwari Parida

School of Veterinary and Biomedical Sciences: Dissertations, Theses, and Student Research

Porcine reproductive and respiratory syndrome virus is a significant swine pathogen which exhibits considerable sequence diversity. In an attempt to identify highly conserved T-cell epitopes contained in proteins of this virus, we examined heptadecamer peptides spanning the sequence of the PRRSV nonstructural proteins 9, 10 and 11, all of them are highly conserved, for their ability to elicit a recall proliferative and interferon-gamma response in peripheral blood mononuclear cells obtained from pigs immunized against the type-II PRRSV strain FL-12. These studies led to the identification of seven peptides, two from each NSP 9 and NSP 10 and, three from NSP …


Modeling Of The Efficacy And Effectiveness Of Escherichia Coli O157:H7 Pre-Harvest Interventions, Amanda R. Vogstad May 2012

Modeling Of The Efficacy And Effectiveness Of Escherichia Coli O157:H7 Pre-Harvest Interventions, Amanda R. Vogstad

School of Veterinary and Biomedical Sciences: Dissertations, Theses, and Student Research

Shiga toxin-producing Escherichia coli O157:H7 (STEC O157) is one of the leading causes of hemolytic uremic syndrome in humans. Reducing the prevalence of STEC O157 in live cattle may reduce ground beef prevalence and subsequent human illness. Type III secreted protein vaccines (TTSP) reduce fecal shedding of STEC O157 in cattle. However, pre-harvest vaccines have yet to be adopted by the beef industry. The objectives of this thesis were to 1) conduct a meta-analysis to test factors effecting efficacy of a 3-dose regimen TTSP vaccine product, and 2) use stochastic simulation to model the usefulness of preharvest control measures. In …


Efficient And Robust Rna-Seq Process For Cultured Bacteria And Complex Community Transcriptomes, Georgia Giannoukos, Dawn M. Ciulla, Katherine Huang, Brian J. Haas, Jacques Izard, Joshua Z. Levin, Jonathan Livny, Ashlee M. Earl, Dirk Gevers, Doyle V. Ward, Chad Nusbaum, Bruce W. Birren, Andreas Gnirke Jan 2012

Efficient And Robust Rna-Seq Process For Cultured Bacteria And Complex Community Transcriptomes, Georgia Giannoukos, Dawn M. Ciulla, Katherine Huang, Brian J. Haas, Jacques Izard, Joshua Z. Levin, Jonathan Livny, Ashlee M. Earl, Dirk Gevers, Doyle V. Ward, Chad Nusbaum, Bruce W. Birren, Andreas Gnirke

Department of Food Science and Technology: Faculty Publications

We have developed a process for transcriptome analysis of bacterial communities that accommodates both intact and fragmented starting RNA and combines efficient rRNA removal with strand-specific RNA-seq. We applied this approach to an RNA mixture derived from three diverse cultured bacterial species and to RNA isolated from clinical stool samples. The resulting expression profiles were highly reproducible, enriched up to 40-fold for non-rRNA transcripts, and correlated well with profiles representing undepleted total RNA.


Effect Of The Infection With Porcine Reproductive And Respiratory Syndrome Virus On The Regulation Of Cytokines: Tumor Necrosis Factor-Alpha And Interleukin-10, Sakthivel Subramaniam Aug 2011

Effect Of The Infection With Porcine Reproductive And Respiratory Syndrome Virus On The Regulation Of Cytokines: Tumor Necrosis Factor-Alpha And Interleukin-10, Sakthivel Subramaniam

School of Veterinary and Biomedical Sciences: Dissertations, Theses, and Student Research

Porcine reproductive and respiratory syndrome virus (PRRSV) causes late-term abortion in sows and pneumonia in growing piglets. PRRSV evades the host immune response by several mechanisms, including the modulation of cytokine secretions in infected pigs, which is the subject of this dissertation. Particularly, PRRSV reduces the secretion of the pro-inflammatory cytokine, tumor necrosis factor-α (TNF-α) but increases the secretion of the anti-inflammatory cytokine interleukin-10 (IL-10). The latter effect, however, is PRRSV strain-specific. In this dissertation, we have examined mechanisms by which PRRSV regulates TNF-α and IL-10 expressions. The pathogenic strain FL12, derived from a PRRSV infectious clone, consistently suppressed TNF-α …


Role Of Porcine Reproductive And Respiratory Syndrome Virus Non-Structural Protein 1 In Viral Replications And Pathogenesis, Lalit Kumar Beura Aug 2011

Role Of Porcine Reproductive And Respiratory Syndrome Virus Non-Structural Protein 1 In Viral Replications And Pathogenesis, Lalit Kumar Beura

School of Veterinary and Biomedical Sciences: Dissertations, Theses, and Student Research

Porcine reproductive and respiratory syndrome virus (PRRSV) is an infectious agent of significant concern to the global swine industry. PRRSV infection of pigs is initiated by a long viremia after which the virus enters in an extended persistent phase of 3-4 months that ultimately is resolved by the immune system. The delayed and weak host adaptive response is responsible for the protracted convalescence period. An initial sub-optimal innate immune response is postulated to be the reason behind such meager adaptive immune response. A major focus of the studies undertaken in this dissertation was to identify the viral non-structural proteins (nsps) …


Identification Of Host Proteins Required For Vesicular Stomatitis Virus Infection, Debasis Panda Aug 2011

Identification Of Host Proteins Required For Vesicular Stomatitis Virus Infection, Debasis Panda

School of Veterinary and Biomedical Sciences: Dissertations, Theses, and Student Research

Viruses usurp host cell pathways for different stages of their infection. Understanding virus-host interaction will be invaluable to elucidate molecular mechanisms of virus infection and to identify drug targets. In order to identify such critical cellular genes in vesicular stomatitis virus (VSV, a model non-segmented negative strand RNA virus) infection, we developed a stable cell line constitutively expressing replication proteins of VSV. Attempts to establish a cell line replicating a sub-genomic replicon was not successful because of induction of interferon response by replication of viral genomic analog. Subsequently, we used siRNA technology and conducted a genome-wide siRNA screen in HeLa …


Minimal Art: Or Why Small Viral K+ Channels Are Good Tools For Understanding Basic Structure And Function Relations, Gerhard Thiel, Dirk Baumeister, Indra Schroeder, Stefan M. Kast, James L. Van Etten, Anna Moroni Jan 2011

Minimal Art: Or Why Small Viral K+ Channels Are Good Tools For Understanding Basic Structure And Function Relations, Gerhard Thiel, Dirk Baumeister, Indra Schroeder, Stefan M. Kast, James L. Van Etten, Anna Moroni

James Van Etten Publications

Some algal viruses contain genes that encode proteins with the hallmarks of K+ channels. One feature of these proteins is that they are less than 100 amino acids in size, which make them truly minimal for a K+ channel protein. That is, they consist of only the pore module present in more complex K+ channels. The combination of miniature size and the functional robustness of the viral K+ channels make them ideal model systems for studying how K+ channels work. Here we summarize recent structure/function correlates from these channels, which provide insight into functional properties such as gating, pharmacology and …


Functional Hak/Kup/Kt-Like Potassium Transporter Encoded By Chlorella Viruses, Timo Greiner, José Ramos, Maria C. Alvarez, James Gurnon, Ming Kang, James L. Van Etten, Anna Moroni, Gerhard Thiel Jan 2011

Functional Hak/Kup/Kt-Like Potassium Transporter Encoded By Chlorella Viruses, Timo Greiner, José Ramos, Maria C. Alvarez, James Gurnon, Ming Kang, James L. Van Etten, Anna Moroni, Gerhard Thiel

James Van Etten Publications

Chlorella viruses are a source of interesting membrane transport proteins. Here we examine a putative K+ transporter encoded by virus FR483 and related chlorella viruses. The protein shares sequence and structural features with HAK/KUP/KT-like K+ transporters from plants, bacteria and fungi. Yeast complementation assays and Rb+ uptake experiments show that the viral protein, termed HAKCV (high-affinity K+ transporter of chlorella virus), is functional, with transport characteristics that are similar to those of known K+ transporters. Expression studies revealed that the protein is expressed as an early gene during viral replication, and proteomics data indicate that it is not packaged in …


Giant Viruses, James L. Van Etten Jan 2011

Giant Viruses, James L. Van Etten

James Van Etten Publications

The common view of viruses, mostly true, is of tiny burglars that sneak into cells, grab the biosynthetic controls and compel the cell to make huge numbers of progeny that break out of the cell and keep the replication cycle going. Viruses are supposed to be diminutive even compared to cells that are just a micrometer (1,000 nanometers) in diameter. They are supposed to travel light, making do with just a few well-adapted genes.

In 1992, a new microorganism was isolated from a power-plant cooling tower in Bradford, England, where Timothy Robotham, a microbiologist at Leeds Public Health Laboratory, was …