Microbiology Commons^™

Encapsidation Of Turnip Crinkle Virus Is Defined By A Specific Packaging Signal And Rna Size, Feng Qu, Thomas Jack Morris

Nebraska Center for Virology: Faculty Publications

A protoplast infection assay has been used to reliably examine the viral RNA encapsidation of turnip crinkle virus (TCV). Analysis of the encapsidation of various mutant viral RNAs revealed that a 186-nucleotide (nt) region at the 3’ end of the coat protein (CP) gene, with a bulged hairpin loop of 28 nt as its most essential element, was indispensable for TCV RNA encapsidation. When RNA fragments containing the 186-nt region were used to replace the CP gene of a different virus, tomato bushy stunt virus, the resulting chimeric viral RNAs were encapsidated into TCV virions. Furthermore, analysis of the encapsidated …

Identification Of The Adp-L-Glycero-D-Manno-Heptose-6-Epimerase (Rfad) And Heptosyltransferase Ii (Rfaf) Biosynthesis Genes From Nontypeable Haemophilus Influenzae 2019, W A. Nichols, B W. Gibson, William Melaugh, N G. Lee, M Sunshine, M A. Apicella

Chemistry Faculty Publications

Haemophilus influenzae is an important human pathogen. The lipooligosaccharide (LOS) of H. influenzae has been implicated as a virulence determinant. To better understand the assembly of LOS in nontypeable H. influenzae (NtHi), we have cloned and characterized the rfaD and rfaF genes of NtHi 2019, which encode the ADP-L-glycero-D-manno-heptose-6-epimerase and heptosyltransferase II enzymes, respectively. This cloning was accomplished by the complementation of Salmonella typhimurium lipopolysaccharide (LPS) biosynthesis gene mutants. These deep rough mutants are novobiocin susceptible until complemented with the appropriate gene. In this manner, we are able to use novobiocin resistance to select for specific NtHi LOS inner core …

Characterization Of A Transposon Tn916-Generated Mutant Of Haemophilus Ducreyi 35000 Defective In Lipooligosaccharide Biosynthesis, B W. Gibson, A A. Campagnari, William Melaugh, M A. Apicella, S Grass, Jing Wang, Katherine L. Palmer, R S. Munson

Chemistry Faculty Publications

To define the role of the surface lipooligosaccharide (LOS) of Haemophilus ducreyi in the pathogenesis of chancroid, Tn916 mutants of H. ducreyi 35000 defective in expression of the murine monoclonal antibody (MAb) 3F11 epitope on H. ducreyi LOS were identified by immunologic screening. One mutant, designated 1381, has an LOS which lacks the MAb 3F11 epitope and migrates with an increased mobility on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The gene disrupted by the Tn916 element in strain 1381 was identified by cloning the sequences flanking the Tn916 element. The sequences were then used to probe a lambda DASHII genomic library. …

Cyanonews (Vol. 13, No. 1, July 1997), Jeff Elhai

CyanoNews

CyanoNews was a newsletter that served the cyanobacteriological community from 1985 to 2003, with content provided by readers (sort of a blog before there were blogs). The newsletter reported new findings from the lab, summaries of recent meetings (often provided by graduate students and post-docs entering the field), positions sought or available, life transitions, a compendium of recent cyanobacteria-related articles, and other items of interest to those who study cyanobacteria.

Detection Of Bovine Immunodeficiency Virus Antibodies In Cattle By Western Blot Assay With Recombinant Gag Protein, Shucheng Zhang, Wenzhi Xue, Charles Wood, Qi-Min Chen, Sanjay Capil, Harish Minocha

Nebraska Center for Virology: Faculty Publications

A western blot assay using purified recombinant bovine immunodeficiency virus gag protein has been developed for detection of bovine immunodeficiency virus antibodies in bovine serum samples. The test was standardized with known bovine immunodeficiency virus positive and negative bovine serum samples and the monoclonal antibody to gag protein. Both naturally and experimentally infected cattle sera demonstrated positive test results. The result of western blot assay was compared with polymerase chain reaction test results in 134 blood samples collected from Kansas. Twenty-six samples tested positive for bovine immunodeficiency virus DNA with polymerase chain reaction (18.7%) and 25 were positive for the …

A Comparative Study Of The Benthic Population In Weir Ponds Draining Watersheds Of The Fernow Experimental Forest, Parsons, West Virginia, Kevin Dwayne Brittingham

Theses, Dissertations and Capstones

A study of the benthos of weir ponds draining watersheds of the Fernow Experimental Forest (FEF) was conducted in 1994-1995. The objectives of this study were: (1) to relate differences in weir pond faunas to watershed treatments on the FEF, and (2) to compare current weir pond faunas to those described in 1973 by Steve Harris. In 1971-1972, there were fewer invertebrates but greater taxa richness than in 1994-1995. Total density varied among weir pond and between studies with numbers in the 1971- 1972 study ranging from 26,168 to 79,259 individuals collected, while numbers in the 1994-1995 study raged from …

An Investigation Of The Acarine Fauna Of Rehabilitated Bauxite Mines In The Northern Jarrah Forest, Alex Cuccovia

Theses : Honours

The northern jarrah forest relies on efficient nutrient cycling for its growth and long term sustainability. The decomposition of organic matter and the recycling of nutrients in such ecosystems are facilitated through the interaction of microflora with a myriad of invertebrates. The recolonisation of invertebrate fauna to rehabilitated bauxite mines is thus of critical importance to the long-term success of rehabilitation. This study investigated the soil and litter mite fauna, important components of the invertebrate community well known for their numerical dominance and high biodiversity. A spring sampling of the mite fauna was undertaken, employing standard soil and litter sampling …

The Impact Of Permaculture On The Above-Ground Mesofaunal Communities In The Perth Metropolitan Area, Ruth C. D'Sanges

Theses : Honours

Conventional agricultural practices (tillage, extensive application of synthetic fertilisers and biocides) exert substantial disturbance on soil ecosystems, consequently causing severe land degradation through loss of soil organic matter. These practices also place significant pressure on the soil inhabitants. However, permaculture systems practice non-tillage and extensive mulching. These non-tillage practices reduce the amount of perturbation on the litter invertebrates and encourage their abundances. The aims of this study were to describe the above-ground mesofaunal communities in the mulch layer of selected urban permaculture systems in the Perth Metropolitan area. This included determining the faunal abundance and diversity. Four permaculture sites were …

Determination Of The Presence Of Antibiotics And Bacterial Pathogens With Their Susceptibility In Fresh Milk From The San Nicolas Community And The Cities Of Penipe, Guano, And Chambo In The Chimborazo Province, Lupe Marín

Theses and Dissertations

This study is entitled, “determination of the presence of antibiotics and bacterial pathogens with their susceptibility in fresh milk from the San Nicolas community and the cities of Penipe, Guano, and Chambo in the Chimborazo province”. It was funded by the Benson Institute of Brigham Young University and Nestle. The objectives were: 1) to determine the presence of antibiotics in fresh milk from the San Nicolas community and the cities of Penipe, Guano, and Chambo, 2) to determine the presence of bacterial pathogens in milk from the places previously mentioned, and 3) to detect the susceptibility of the isolated bacteria …

Stem Cell Factor And Kit Expression In Type I Neurofibromatosis, Kenneth Eugene Roth

Theses and Dissertations

Neurofibromatosis type 1 (NF1) is an inherited disease characterized by the appearance of multiple neurofibromas and an increased incidence of malignant schwannomas, both of which contain hyperproliferative Schwann cells. Our laboratory previously reported that Schwann cells produce stem cell factor (SCF), a multi potential growth factor known to be involved in mast cell migration and growth. Given the fact that mast cell numbers are increased in both neurofibromas and malignant schwannomas, we set out to evaluate a potential role for SCF in the development of NF1 lesions. First we studied the effects of high doses of recombinant SCF on mast …

Interleukin-2 Activated Lymphocytes Use Cd11b/Cd18 For Adhesion To Candida Albicans, Christopher B. Forsyth

Dissertations

No abstract provided.

Physiological Role Of The Short Form Of The Histidine Protein Kinase, Cheas, In Bacterial Chemotaxis, Barry Patrick Mcnamara

Dissertations

No abstract provided.

Structure-Function Analysis Of The Catalytic Domain Of The Histidine Kinase Chea, Dolph David Ellefson

Dissertations

No abstract provided.

Testability Properties Of Divergent Trees, Ronald D. Blanton, John P. Hayes

University Faculty Publications and Creative Works

The testability of a class of regular circuits called divergent trees is investigated under a functional fault model. Divergent trees include such practical circuits as decoders and demultiplexers. We prove that uncontrolled divergent trees are testable with a fixed number of test patterns (C-testable) if and only if the module function is surjective. Testable controlled trees are also surjective but require sensitizing vectors for error propagation. We derive the conditions for testing controlled divergent trees with a test set whose size is proportional to the number of levels p found in the tree (L-testability). By viewing a tree as overlapping …

Altered Pathogenesis Of A Mutant Of The Murine Coronavirus Mhv-A59 Is Associated With A Q159l Amino Acid Substitution In The Spike Protein, Isabelle Leparc-Goffart, Susan T. Hingley, Ming Chua, Xinhe Jiang, Ehud Lavi, Susan R. Weiss

PCOM Scholarly Works

C12, an attenuated, fusion delayed, very weakly hepatotropic mutant of mouse hepatitis virus strain A59 (MHV-A59) has been further characterized. We have previously shown that C12 has two amino acid substitutions relative to wild type virus in the spike protein, Q159L (within a region of S1 shown to bind to viral receptor in an in vitro assay) and H716D (in the proteolytic cleavage recognition site). We have sequenced the rest of the 31-kb genome of C12 and compared it to wild type virus. Only three additional amino acids substitutions were found, all encoded within the replicase gene. Analysis of C12 …

Cyclic Amp And Its Receptor Protein Negatively Regulate The Coordinate Expression Of Cholera Toxin And Toxin-Coregulated Pilus In Vibrio Cholerae, Karen Skorupski, Ronald K. Taylor

Dartmouth Scholarship

Insertion mutations in two Vibrio cholerae genes, cya and crp, which encode adenylate cyclase and the cyclic AMP (cAMP) receptor protein (CRP), respectively, derepressed the expression of a chromosomal cholera toxin (CT) promoter-lacZ fusion at the nonpermissive temperature of 37 degrees C. In the classical biotype strain O395, the crp mutation increased the production of both CT and toxin-coregulated pilus (TCP) in vitro under a variety of growth conditions not normally permissive for their expression. The most dramatic increase in CT and TCP was observed with the crp mutant in Luria-Bertani (LB) medium pH 8.5, at 30 degrees C. El …

Ventilation Rates For Carassius Auratus During Changes In Dissolved Oxygen, Collin Nolan

UNLV Theses, Dissertations, Professional Papers, and Capstones

This experiment was designed to determine whether dissolved oxygen concentrations would influence the ventilation rate of goldfish, Carassius auratus. Ventilation rate can be determined by counting opercular movements. Opercular movements of the same five goldfish were counted at three different levels of dissolved oxygen to determine whether there were differences in ventilation rates. Average ventilation rates were established for each of the three levels of dissolved oxygen and compared statistically. There were significant differences in the ventilation rates averages at each of the three levels. Carassius auratus will exhibit changes in ventilation rates when dissolved oxygen levels change.

The Bradyrhizobium Japonicum Fega Gene Encodes An Iron-Regulated Outer Membrane Protein With Similarity To Hydroxamate-Type Siderophore Receptors., Kristin Levier, Mary Lou Guerinot

Dartmouth Scholarship

Iron is important in the symbiosis between soybean and its nitrogen-fixing endosymbiont Bradyrhizobium japonicum, yet little is known about rhizobial iron acquisition strategies. Analysis of outer membrane proteins (OMPs) from B. japonicum 61A152 identified three iron-regulated OMPs in the size range of several known receptors for Fe(III)-scavenging siderophores. One of the iron-regulated proteins, FegA, was purified and microsequenced, and a reverse genetics approach was used to clone a fegA-containing DNA fragment. Sequencing of this fragment revealed a single open reading frame of 750 amino acids. A putative N-terminal signal sequence of 14 amino acids which would result in a mature …

Diseased Thyrocytes Have Aberrant Communication And Tnf Receptor Secretion, Mary Labue

Loma Linda University Electronic Theses, Dissertations & Projects

Autoimmune diseases are a world-wide health concern and are an intense area of investigation. However, one area of research has been largely ignored. This involves the contribution of the target tissue to the disease process. We hypothesized that cell-cell communication is disrupted by lymphocytic infiltration and advancing fibrosis and this disruption results in altered target cell responses to immune components produced at the site of inflammation, including Tumor Necrosis Factor-alpha (TNF- α).

We have used thyroiditis as our model of autoimmunity and have documented the development of spontaneous thyroiditis in MRL-lpr/lpr mice. We have found aberrant connexin expression in …

Structural And Functional Analysis Of Secondary Structure Block To Mrna Utilization, Juan Lin

Loma Linda University Electronic Theses, Dissertations & Projects

Experimentally introduced secondary structure, formed by a cis-targeted hammerhead ribozyme in exon 2 two nucleotides dowstream of the 3' splice site of a yeast ACT-E. coli lacZ fusion gene, virtually abolishes splicing in vivo and inhibits B-galactosidase production. This is the first demonstration of the splicing inhibitory effect of secondary structures occurring in exons in the absence of splice site sequestration. Our goal is to understand the mechanism by which utilization of this splice site is impeded. Two cis - and one trans-acting mutations that alleviate the splicing blockage were obtained by screening for restoration of B-galactosidase activity. Both cis …

About The Cellular Tropism Of The Gammaherpesvirus Bovine Herpesvirus Type 4, Fernando A. Osorio, J. A. Galeota-Wheeler, D. E. Reed, O. Lopez

Nebraska Center for Virology: Faculty Publications

We read with interest the recent report by Egyed et al. (4) about the distribution in tissue, in the natural host, of bovine herpesvirus type 4 (BHV-4), a member of the gammaherpesvirus group. Using PCR, those authors were able to trace BHV-4 (Movar strain) in several tissues of experimentally infected cattle (mostly spleen, lung, trachea, and nasal epithelium tissues) at different times, ranging from 3 to 48 days postinfection. The authors also report consistent detection of BHV-4 DNA in what they consider to be a pure population of lymphocytes obtained from peripheral blood of the BHV-4- infected cattle, and then …

Effect Of Sediment Particle Size And Temperature On Fecal Bacteria Mortality Rates And The Fecal Coliform/Fecal Streptococci Ratio, J. M. Howell, Mark S. Coyne, P. L. Cornelius

Plant and Soil Sciences Faculty Publications

Extended survival of fecal bacteria in sediment can obscure the source and extent of fecal contamination in agricultural settings. The variability in fecal coliform/fecal streptococci (FC/FS) ratios with time and discrepancies between observable fecal sources and measured FC/FS ratios in shallow surface water from agricultural watersheds may be explained by examining FC and FS mortality rates in response to ambient temperature and sediment particle size. We measured FC and FS mortality rates at three different temperatures and in three feces-amended sediments with different particle size in a laboratory study. In controlled conditions, using physiological saline to reduce cell death by …

Human Herpesvirus Type 8 Dna Sequences In Cell-Free Plasma And Mononuclear Cells Of Kaposi's Sarcoma Patients, William J. Harrington, Omar Bagasra, Carlos E. Sosa, Lisa E. Bobroski, Marianna Baum, Xue Lan Wen, Lisa Cabral, Gerald E. Byrne, Roger J. Pomerantz, Charles Wood

Nebraska Center for Virology: Faculty Publications

Human herpesvirus (HHV) type 8 bas been detected in both classical and AIDS-related Kaposi's sarcoma, body-cavity lymphomas, and other types of tumors. HHV-8 has also been detected in DNA from peripheral blood mononuclear cells (PBMC) of some Kaposi's sarcoma patients and more readily in B cell fractions derived from panned cell subpopulations. Two patients were followed using several methods: in situ hybridization, solution-based polymerase chain reaction (PCR), and in situ PCR. HHV-8 was intermittently detected in plasma and detection correlated with detection in PBMC. In situ PCR demonstrated HHV-8 sequences in both peripheral blood B lymphocytes and, to a lesser …

Parotid Gland Lipoma: A Rare Entity, S Muzaffar, N Kayani, S H. Hasan

Department of Pathology and Laboratory Medicine

No abstract provided.

A Role For A Rab4-Like Gtpase In Endocytosis And In Regulation Of Contractile Vacuole Structure And Function In Dictyostelium Discoideum, John Bush, Lesly A. Temesvari, Juan Rodriguez-Paris, Greg Buczynski, James Cardelli

Publications

The small Mr Rab4-like GTPase, RabD, localizes to the endosomal pathway and the contractile vacuole membrane system in Dictyostelium discoideum. Stably transformed cell lines overexpressing a dominant negative functioning RabD internalized fluid phase marker at 50% of the rate of wild-type cells. Mutant cells were also slower at recycling internalized fluid. Microscopic and biochemical approaches indicated that the transport of fluid to large postlysosome vacuoles was delayed in mutant cells, resulting in an accumulation in acidic smaller vesicles, probably lysosomes. Also, RabD N121I-expressing cell lines missorted a small but significant percentage of newly synthesized lysosomal alpha-mannosidase precursor polypeptides. However, the …

Genetic And Phylogenetic Divergence Of Feline Immunodeficiency Virus In The Puma (Puma Concolor), Margaret A. Carpenter, Eric W. Brown, Melanie Culver, Warren E. Johnson, Jill Pecon-Slattery, Dulce Brousset, Stephen J. O'Brien

Biology Faculty Articles

Feline immunodeficiency virus (FIV) is a lentivirus which causes an AIDS-like disease in domestic cats (Felis catus). A number of other felid species, including the puma (Puma concolor), carry a virus closely related to domestic cat FIV. Serological testing revealed the presence of antibodies to FIV in 22% of 434 samples from throughout the geographic range of the puma. FIV-Pco pol gene sequences isolated from pumas revealed extensive sequence diversity, greater than has been documented in the domestic cat. The puma sequences formed two highly divergent groups, analogous to the clades which have been defined for …

Bacillus Thuringiensis Hd-73 Spores Have Surface-Localized Cry1ac Toxin: Physiological And Pathogenic Consequences, Cheng Du, Kenneth Nickerson

Papers in Microbiology

Spores from Cry⁺ strains of Bacillus thuringiensis bound fluorescein isothiocyanate-labeled antibodies specific for the 65-kDa activated Cry 1Ac toxin, whereas spores from Bacillus cereus and Cry^- strains of B. thuringiensis did not. The Cry⁺ spores could be activated for germination by alkaline conditions (pH 10.3), whereas Cry^- spores could not. Once the surrounding exosporia had been removed or permeabilized, Cry⁺ spores were able to bind the toxin receptor(s) from insect gut brush border membrane vesicle preparations, and their germination rates were increased ca. threefold in the presence of brush border membrane vesicles. A model is …

Characterization Of P39, A Borrelia Burgdorferi Specific Protein, Jill M. Troyer

Theses and Dissertations in Biomedical Sciences

Borrelia burgdorferi, the causative agent of Lyme disease, expresses a species specific, 39 kiloDalton protein of unknown function called P39. This protein is highly immunogenic and the presence of anti-P39 antibodies in patient sera is used as an indicator of B. burgdorferi infection. P39 is also a candidate for vaccine developement due to conserved expression of P39 among B. burgdorferi isolates. Since little is presently known about this important molecule, the present study was designed to characterize P39 and was carried out in six separate investigations. First, infectious and noninfectious isolates of B. burgdorferi were established in vitro, and …

Crystal Protein Expression During Vegetative Growth Of Dictyostelium, Kristy K. Taylor, Catherine P. Chia

Papers in Microbiology

We are studying interactions between membrane proteins and the cytoskeleton of Dictyostelium discoideum. Detergent (Triton X-100) -insoluble cytoskeletons from vegetative (AX2) amebae are enriched in a 70 kDa Concanavalin A (Con A)-binding protein (gp70). An enriched fraction of gp70 was prepared by Con A affinity chromatography of cytoskeletons from axenically-grown cells. N-terminal amino acid sequence of gel-purified gp70 established its identity to a 69 kDa 'crystal protein' previously characterized by Bomblies, et al. (1990, J. Cell Biol. 110:669 -679). Enzymatic deglycosylation of gp70 resulted in a 65 kDa product that did not bind Con A, verifying the predicted number …

In Vivo Detection Of Porcine Reproductive And Respiratory Syndrome Virus Rna By In Situ Hybridization At Different Times Post-Infection, Jung-Hyang Sur, Vicki Cooper, Judith A. Galeota, Richard A. Hesse, Alan R. Doster, Fernando A. Osorio

Nebraska Center for Virology: Faculty Publications

We studied the distribution of porcine reproductive and respiratory syndrome virus (PRRSV) RNA in tissues by in situ hybridization at different times postinfection (p.i.). The probe used for in situ hybridization was prepared by reverse transcription of PRRSV RNA, followed by PCR amplification of the cDNA. The sequence amplified corresponded to 433 bp from PRRSV open reading frame 7, which is contained in the nucleocapsid protein gene and which is highly conserved in both European and American strains (H. Mardassi, L. Wilson, S. Mounir, and S. Dea, J. Clin. Microbiol. 32:2197–2203, 1994). An immunohistochemical technique was used to detect PRRSV …