Microbiology Commons^™

Evolutionary Variation Of Papillomavirus E2 Protein And E2 Binding Sites, Adam Rogers, Mackenzie Waltke, Peter C. Angeletti

Nebraska Center for Virology: Faculty Publications

Background: In an effort to identify the evolutionary changes relevant to E2 function, within and between papillomavirus genera, we evaluated the E2 binding sites (E2BS)s inside the long-control-region (LCR), and throughout the genomes. We identified E2BSs in the six largest genera of papillomaviruses: Alpha, Beta, Gamma, Delta, Lambda, and Xi-papillomaviruses (128 genomes), by comparing the sequences with a model consensus we created from known functional E2BSs (HPV16, HPV18, BPV1). We analyzed the sequence conservation and nucleotide content of the 4-nucleotide spacer within E2BSs. We determined that there is a statistically significant difference in GC content of the four-nucleotide E2BS …

Tetherin Inhibits Prototypic Foamy Virus Release, Fengwen Xu, Juan Tan, Ruikang Liu, Dan Xu, Yue Li, Yunqi Geng, Chen Liang, Wentao Qiao

Nebraska Center for Virology: Faculty Publications

Background: Tetherin (also known as BST-2, CD317, and HM1.24) is an interferon- induced protein that blocks the release of a variety of enveloped viruses, such as retroviruses, filoviruses and herpesviruses. However, the relationship between tetherin and foamy viruses has not been clearly demonstrated.

Results: In this study, we found that tetherin of human, simian, bovine or canine origin inhibits the production of infectious prototypic foamy virus (PFV). The inhibition of PFV by human tetherin is counteracted by human immunodeficiency virus type 1 (HIV-1) Vpu. Furthermore, we generated human tetherin transmembrane domain deletion mutant (delTM), glycosyl phosphatidylinositol (GPI) anchor …

Kaposi Sarcoma-Associated Herpesvirus Degrades Cellular Toll-Interleukin-1 Receptor Domain-Containing Adaptor-Inducing Β-Interferon (Trif), Humera Ahmad, Rachel Gubbels, Florencia Meyer, Thomas Waterbury, Rongtuan Lin, Luwen Zhang

Nebraska Center for Virology: Faculty Publications

Kaposi sarcoma-associated herpesvirus (KSHV) is a human ƴ - herpesvirus associated with several human malignancies. The replication and transcription activator (RTA) is necessary and sufficient for the switch from KSHV latency to lytic replication. Toll-interleukin-1 receptor (TIR) domain-containing adaptorinducing β-interferon (TRIF, also called TIR-domain-containing adaptor molecule-1 (TICAM-1)) is a signaling adaptor molecule that is critically involved in the Toll-like receptor 3 (TLR-3) and TLR-4 signaling pathways for type I interferon (IFN) production, a key component of innate immunity against microbial infection. In this report, we find a new mechanism by which RTA blocks innate immunity by targeting cellular TRIF. RTA …

Robust Rnai-Based Resistance To Mixed Infection Of Three Viruses In Soybean Plants Expressing Separate Short Hairpins From A Single Transgene, Xiuchun Zhang, Shirley Sato, Xiaohong Ye, Anne E. Dorrance, Thomas Jack Morris, Thomas E. Clemente, Feng Qu

Nebraska Center for Virology: Faculty Publications

Transgenic plants expressing double-stranded RNA (dsRNA) of virus

origin have been previously shown to confer resistance to virus infections

through the highly conserved RNA-targeting process termed RNA silencing

or RNA interference (RNAi). In this study we applied this strategy to

soybean plants and achieved robust resistance to multiple viruses with a

single dsRNA-expressing transgene. Unlike previous reports that relied

on the expression of one long inverted repeat (IR) combining sequences

of several viruses, our improved strategy utilized a transgene designed to

express several shorter IRs. Each of these short IRs contains highly conserved

sequences of one virus, forming dsRNA of …

Critical Role Of Leucine-Valine Change In Distinct Low Ph Requirements For Membrane Fusion Between Two Related Retrovirus Envelopes, Marceline Côté, Yi-Min Zheng, Kun Li, Shi-Hua Xiang, Lorraine M. Albritton, Shan-Lu Liu

Nebraska Center for Virology: Faculty Publications

Many viruses use a pH-dependent pathway for fusion with host cell membrane, the mechanism of which is still poorly understood. Here we report that a subtle leucine (Leu)-valine (Val) change at position 501 in the envelope glycoproteins (Envs) of two related retroviruses, jaagsiekte sheep retro-virus (JSRV) and enzootic nasal tumor virus (ENTV), is responsible for their distinct low pH requirements for membrane fusion and infection. The Leu and Val residues are predicted to reside within the C-terminal heptad repeat (HR2) region of JSRV and ENTV Envs, particularly proximal to the hairpin turn of the putative six-helix bundle (6HB). Substitution of …

Hiv-1 Clade B And C Isolates Exhibit Differential Replication: Relevance To Macrophage-Mediated Neurotoxicity, Agnes A. Constantino, Yunlong Huang, Hong Zhang, Charles Wood, Jialin C. Zheng

Nebraska Center for Virology: Faculty Publications

HIV-associated neurocognitive disorders (HAND) continue to be a consequence of HIV-1 infection among clade B-infected individuals. In contrast, the incidence of severe neurological impairment is lower among clade C-infected patients in regions of Sub-Saharan Africa and India. Biological aspects such as replication, cytopathicity, inflammatory response, and neurotoxicity unique to each clade influence neuropathogenicity and ultimately affect the clinical outcome of the disease. We hypothesize that productive infection by clade C isolates leads to macrophagemediated neurotoxicity, although to a lesser extent than clade B isolates. Using a panel of primary isolates of clades B and C we demonstrated that clade B …

Hiv-1 Effects On Neuropsychological Performance In A Resource-Limited Country, Zambia, Gabriel Holguin, Mwanza Banda, Elizabeth J. Willen, Costantine Malama, Kaseya O. Chiyenu, Victor C. Mudenda, Charles Wood

Nebraska Center for Virology: Faculty Publications

Zambia has substantially been affected by the HIV/AIDS epidemic with prevalence rates at 14% in a population estimated at 12 million. Yet, the extent of HIV-associated neurocognitive disorders (HAND) in this population remains to be clearly understood. A series of culturally appropriate neuropsychological (NP) assessments [International HIV Dementia Scale (IHDS), Color Trails Test 1 and 2, Grooved pegboard Test, and Time Gait Test] were used to test the effects of HIV on NP performance of HIV seropositive and seronegative individuals. Twenty-two percent HIV positive individuals ARV naïve met the criteria for IHDS-defined NP impairment. Gender significantly influenced the performance on …

The Zambia Children's Ks-Hhv8 Study: Rationale, Study Design, And Study Methods, Veenu Minhas, Kay L. Crabtree, Ann Chao, Janet M. Wojcicki, Adrian M. Sifuniso, Catherine Nkonde, Chipepo Kankasa, Charles D. Mitchell, Charles Wood

Nebraska Center for Virology: Faculty Publications

The epidemic of human immunodeficiency virus in Zambia has led to a dramatic rise in the incidence of human herpesvirus-8 (HHV-8)–associated Kaposi's sarcoma in both adults and children. However, there is a paucity of knowledge about the routes of HHV-8 transmission to young children. The Zambia Children's KS-HHV8 Study, a large, prospective cohort study in Lusaka, Zambia, was launched in 2004 to investigate the role of household members as a source of HHV-8 infection in young children and social behaviors that may modify the risk of HHV-8 acquisition. This cohort is distinct from other epidemiologic studies designed to investigate HHV-8 …

Prevalence Of Human Herpesvirus 8 (Hhv8) And Hepatitis C Virus (Hcv) In A Rural Community With High Risk For Blood Borne Infections In Central China, Tiejun Zhang, Na He, Yingying Ding, Kay L. Crabtree, Veenu Minhas, Charles Wood

Nebraska Center for Virology: Faculty Publications

Former illegal blood donation in the past decade has caused HIV outbreaks in some rural areas in China. Other HIV associated virus infections, such as human herpesvirus 8 (HHV8) in such areas are still not well defined. In order to explore HHV8 and HCV seroprevalence and potential risk factors in such areas, a cross-sectional study with 305 HIV positive and 315 HIV negative subjects recruited from a rural county in Shanxi province was conducted, where illegal blood collection was reported. Interview questionnaires and serum testing were carried out with these participants. HCV and HHV8 seroprevalence were found to be higher …

Comparison Of Adenoviruses As Oncolytics And Cancer Vaccines In An Immunocompetent B Cell Lymphoma Model, Eric A. Weaver, Christopher Y. Chen, Shannon M. May, Mary E. Barry, Michael A. Barry

Nebraska Center for Virology: Faculty Publications

We have screened human adenoviruses (Ads) for oncolytic activity against a variety of mouse and hamster cell lines and have found a number that are susceptible to a variety of Ad serotypes. A20 lymphoma is derived from BALB/c mice and is susceptible to infection and killing by a variety of human Ads. A20 is also a suitable cancer vaccine model, because these cells express a unique immunoglobulin variable region that can be targeted by vaccination. To compare Ads as cancer vaccines versus Ads as oncolytics, A20 tumors were initiated in im- munocompetent BALB/c mice. Mice immunized with first-generation Ad5 expressing …

Species D Adenoviruses As Oncolytics Against B-Cell Cancers, Christopher Y. Chen, Julien S. Senac, Eric A. Weaver, Shannon M. May, Diane F. Jelinek, Philip Greipp, Thomas Witzig, Michael A. Barry

Nebraska Center for Virology: Faculty Publications

Purpose: Oncolytic viruses are self-amplifying anticancer agents that make use of the natural ability of viruses to kill cells. Adenovirus serotype 5 (Ad5) has been extensively tested against solid cancers, but less so against B-cell cancers because these cells do not generally express the coxsackie and adenoviral receptor (CAR). To determine whether other adenoviruses might have better potency, we "mined" the adenovirus virome of 55 serotypes for viruses that could kill B-cell cancers.

Experimental Design: Fifteen adenoviruses selected to represent Ad species B, C, D, E, and F were tested in vitro against cell lines and primary patient B-cell cancers …

Characterization Of Species C Human Adenovirus Serotype 6 (Ad6), Eric A. Weaver, Reeti Khare, Mathew L. Hillestad, Donna Palmer, Philip Ng, Michael A. Barry

Nebraska Center for Virology: Faculty Publications

Adenovirus serotype (Ad5) is the most studied Ad. Ad1, 2, and 6 are also members of species C Ad and are presumed to have biologies similar to Ad5. In this work, we have compared the ability of Ad1, 2, 5, and 6 to infect liver and muscle after intravenous and intramuscular injection. We found that Ad6 was surprisingly the most potent at liver gene delivery and that Ad1 and Ad2 were markedly weaker than Ad5 and 6. To understand these differences, we sequenced the Ad6 genome. This revealed that the Ad6 fiber protein is surprisingly three shaft repeats shorter than …

Generation Of A Kupffer Cell-Evading Adenovirus For Systemic And Liver-Directed Gene Transfer, Reeti Khare, Shannon M. May, Francesco Vetrini, Eric A. Weaver, Donna Palmer, Amanda Rosewell, Nathan Grove, Philip Ng, Michael A. Barry

Nebraska Center for Virology: Faculty Publications

As much as 90% of an intravenously (i.v.) injected dose of adenovirus serotype 5 (Ad5) is absorbed and destroyed by liver Kupffer cells. Viruses that escape these cells can then transduce hepatocytes after binding factor X (FX). Given that interactions with FX and Kupffer cells are thought to occur on the Ad5 hexon protein, we replaced its exposed hypervariable regions (HVR) with those from Ad6. When tested in vivo in BALB/c mice and in hamsters, the Ad5/6 chimera mediated >10 times higher transduction in the liver. This effect was not due to changes in FX binding. Rather, Ad5/6 appeared to …

Dur3 Is The Major Urea Transporter In Candida Albicans And Is Co-Regulated With The Urea Amidolyase Dur1,2, Dhammika H. M. L. P Navarathna, Aditi Das, Joachim Morschhauser, Kenneth W. Nickerson, David D. Roberts

Kenneth Nickerson Papers

Hemiascomycetes, including the pathogen Candida albicans, acquire nitrogen from urea using the urea amidolyase Dur1,2, whereas all other higher fungi use primarily the nickel-containing urease. Urea metabolism via Dur1,2 is important for resistance to innate host immunity in C. albicans infections. To further characterize urea metabolism in C. albicans we examined the function of seven putative urea transporters. Gene disruption established that Dur3, encoded by orf 19.781, is the predominant transporter. [¹⁴C]Urea uptake was energy-dependent and decreased approximately sevenfold in a dur3D mutant. DUR1,2 and DUR3 expression was strongly induced by urea, whereas the other putative transporter genes …

Western Australia's Biosecurity, Department Of Agriculture And Food, Western Australia, Department Of Environment And Conservation, Western Australia, Department Of Fisheries, Western Australia, Forest Products Commission, Western Australia

Biosecurity published reports

Biosecurity is the protection of the economy, environment and human health from the negative impacts of pests, weeds and diseases, including the management of invasive species if they become established (definition adopted by AusBIOSEC).

This requires steps to prevent the entry of harmful organisms, as well as the timely and efficient management of them if they do enter.

Biosecurity threats range from catastrophic diseases such as Foot and Mouth Disease, which causes rapid and widespread animal deaths, to more subtle and slower spreading problems such as invasive weeds, mussels that foul vessel hulls and fungus-induced dieback disease of trees. These …

Estimating The Impact Of Human Papillomavirus (Hpv) Vaccination On Hpv Prevalence And Cervical Cancer Incidence In Mali, Leree Tracy, Holly Gaff, Colleen Burgess, Samba Sow, Patti E. Gravitt, J. Kathleen Tracy

Biological Sciences Faculty Publications

Human papillomavirus vaccines have potential to reduce cervical cancer incidence and mortality; however, cultural and economic barriers may hinder success in developing countries. We assessed impact of a single vaccine campaign in Mali with use of mathematical modeling. Our model shows that decreases in the prevalence of Human papillomavirus infection are proportional to achieved vaccination coverage.

Potential Fossil Endoliths In Vesicular Pillow Basalt, Coral Patch Seamount, Eastern North Atlantic Ocean, Barbara Cavalazzi, Frances Westall, Sherry L. Cady, Roberto Barbieri, Frédéric Foucher

Geology Faculty Publications and Presentations

The chilled rinds of pillow basalt from the Ampere-Coral Patch Seamounts in the eastern North Atlantic were studied as a potential habitat of microbial life. A variety of putative biogenic structures, which include filamentous and spherical microfossil-like structures, were detected in K-phillipsite-filled amygdules within the chilled rinds. The filamentous structures (similar to 2.5 mu m in diameter) occur as K-phillipsite tubules surrounded by an Fe-oxyhydroxide (lepidocrocite) rich membranous structure, whereas the spherical structures (from 4 to 2 mu m in diameter) are associated with Ti oxide (anatase) and carbonaceous matter. Several lines of evidence indicate that the microfossil-like structures in …

Biosolar Conversion Of N2 And H2o To Ammonia By Engineered N2-Fixing Cyanobacteria, Seth T. Harris

The Journal of Undergraduate Research

The cyanobacterium Anabaena sp. PCC 7120 is capable of using solar energy to produce ammonia through conversion of atmospheric dinitrogen in differentiated cells called heterocysts. Harnessing this system could enable cyanobacteria to be used in ammoniafertilizer production, creating a renewable alternative to the current Haber-Bosch process. The genes patA and alr3304 in the Anabaena 7120 genome are important in heterocyst formation; an increase in heterocyst formation is seen with over-expression of patA or inactivation of alr3304. This research aims to create a novel mutant that forms more heterocysts by simultaneously over-expressing patA and inactivating alr3304, producing higher amounts of ammonia. …

Synthesis And Antimicrobial Activities Of S,S'-Heterosubstituted Disulfides, Praveen Ramaraju

USF Tampa Graduate Theses and Dissertations

Antibiotic resistance is a particularly critical health concern and has increased dramatically over the past two decades. For over a decade the Turos laboratory has been designing small molecules to target pathogenic microbes such as Staphylococcus aureus and the resistant variants like methicillin-resistant Staphylococcus aureus (MRSA). Previously, N-thiolated Β-lactams, N-thiolated 2-oxazolidinones and aromatic disulfides that were synthesized in Dr. Turos' lab have shown strong activity against these bacteria. The present work describes the synthesis and antimicrobial activities of a related structural class called S,S'-heterosubstituted disulfides. For ages, sulfur (elemental) has been used as an antibacterial for controlling infestation and bacterial …

Characterization Of Aminopeptidase Pepz In Staphylococcus Aureus Virulence, Tiffany Marie Robison

USF Tampa Graduate Theses and Dissertations

Staphylococcus aureus is a remarkably successful pathogen, accounting for an estimated 95,000 invasive infections annually in the U.S. alone. The burden of MRSA infections on public healthcare continues to rise, particularly with the continued spread of antibiotic resistant strains and the hyper-virulent CA-MRSA strains. The pathogenic nature of S. aureus can be attributed to the cache of virulence factors encoded within the genome of this organism. Typically, these are secreted toxins which directly interact with the host during infection, and facilitate pathogenesis. A previous screen in our laboratory investigating proteases in S. aureus identified a mutant in aminopeptidase Z as …