Microbiology Commons^™

Cysticercosis In A Muslim Woman, Farrukh Aijaz, Altaf Ahmed

Department of Pathology and Laboratory Medicine

No abstract provided.

The Distribution And Occurrence Of Aerobic Heterotrophic Antimicrobic-Producing Bacteria Isolated From The Lower Chesapeake Bay, Linda Lea Gilmer

Biological Sciences Theses & Dissertations

Three different estuarine microenvironments in the lower Chesapeake Bay were investigated for the occurrence and geographical distribution of antimicrobic-producing bacteria. Samples were taken from the water column, fish skin, and algal surfaces. A total of 1472 bacterial isolates were assayed for antimicrobial activity against fungal, Gram-negative and Gram-positive bacterial test organisms. Of the total bacterial isolates assayed, 5. 2% were active antimicrobic producers. Algal surf aces were shown to have a higher incidence of antimicrobic-producing bacteria than the water column or fish skin. No antimicrobic activity was demonstrated by bacteria isolated from the flounder fish skin. The majority of the …

Salmonella Hadar Pericarditis, A Aziz, W Jafri, T A. Jawed, A Shaikh, B Farooqui, M K. Ashfaq, N Ul Haq

Department of Pathology and Laboratory Medicine

No abstract provided.

Sediment-Water Nutrient Flux In Tidal Creeks Of North Inlet, South Carolina, Michael Duane Quillen

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Arts and Sciences at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Biology by Michael Duane Quillen on December 7, 1992.

Loss Of Infectivity By Progeny Virus From Alpha Interferon- Treated Human Immunodeficiency Virus Type 1-Infected T Cells Is Associated With Defective Assembly Of Envelope Gp120, Brian D. Hanson, Peter L. Nara, Radha K. Maheshwari, Girmel S. Sidhu, John G. Bernbaum, David Hoekzema, Monte S. Meltzer, Howard Gendelman

Nebraska Center for Virology: Faculty Publications

Levels of human immunodeficiency virus (HIV) DNA, RNA, or p24 antigen and reverse transcriptase activity in T-cell cultures treated with 500 IU of recombinant alpha interferon (rIFNα) per ml were comparable to those in control cultures. Radioimmunoprecipitation analysis of proteins in lysates of IFN-treated T cells documented a marked accumulation of HlV proteins. Localization of gp120 by immunofluorescence showed a diffuse pattern in IFN-treated cells quite distinct from the ring pattern in untreated control cells. That large quantities of a120 in aberrant cell compartments might affect HlV morphogenesis was confirmed in infectivity studies: virions from IFN-treated cells were 100- to …

Processing And Localization Of Dengue Virus Type 2 Polyprotein Precursor Ns3-Ns4a-Ns4b-Ns5, Luwen Zhang, P. Maruthi Mohan, R. Padmanabhan

Nebraska Center for Virology: Faculty Publications

Processing of dengue virus type 2 polyprotein precursor NS3-NS4A-NS4B-NS5 could be mediated by the catalytically active NS3 protease domain and NS2B in trans at the dibasic sites NS3-NS4A and NS4B-NS5. Subcellular localization of the unprocessed precursor NS3-NS4A-NS4B-NS5 showed that it was confined to a distinct subcellular organelle in the cytoplasm, which was distinct from the distribution of the mature NS5.

The Entner-Doudoroff Pathway In Escherichia Coli Is Induced For Oxidative Glucose Metabolism Via Pyrroloquinoline Quinone-Dependent Glucose Dehydrogenase, Ronda Fliege, Suxiang Tong, Annemarie Shibata, Kenneth W. Nickerson, Tyrrell Conway

Papers in Microbiology

The Entner-Doudoroff pathway was shown to be induced for oxidative glucose metabolism when Escherichia coli was provided with the periplasmic glucose dehydrogenase cofactor pyrroloquinoline quinone (PQQ). Induction of the Entner-Doudoroff pathway by glucose plus PQQ was established both genetically and biochemically and was shown to occur in glucose transport mutants, as well as in wild-type E. coli. These data complete the body of evidence that proves the existence of a pathway for oxidative glucose metabolism in E. coli. PQQ-dependent oxidative glucose metabolism provides a metabolic branch point in the periplasm; the choices are either oxidation to gluconate followed …

Worldwide Prevalence Of Lentivirus Infection In Wild Feline Species: Epidemiologic And Phylogenetic Aspects, Robert A. Olmstead, Raymond Langley, Melody E. Roelke, Robert M. Goeken, Diane Adger-Johnson, Julie P. Goff, John P. Albert, Craig Packer, M. Karen Laurenson, Tim M. Caro, Lue Scheepers, David E. Wildt, Mitchell Bush, Janice S. Martenson, Stephen J. O'Brien

Biology Faculty Articles

The natural occurrence of lentiviruses closely related to feline immunodeficiency virus (FIV) in nondomestic felid species is shown here to be worldwide. Cross-reactive antibodies to FIV were common in several free-ranging populations of large cats, including East African lions and cheetahs of the Serengeti ecosystem and in puma (also called cougar or mountain lion) populations throughout North America. Infectious puma lentivirus (PLV) was isolated from several Florida panthers, a severely endangered relict puma subspecies inhabiting the Big Cypress Swamp and Everglades ecosystems in southern Florida. Phylogenetic analysis of PLV genomic sequences from disparate geographic isolates revealed appreciable divergence from domestic …

Identification And Characterization Of The Bovine Immunodeficiency-Like Virus Tat Gene, Zhen-Qian Liu, Deborah Sheridan, Charles Wood

Nebraska Center for Virology: Faculty Publications

A cDNA clone of the bovine immunodeficiency-like virus (BW) trans-activator gene (tat) was identified and characterized. The tat cDNA clone was generated by splicing, and on the basis of sequence analysis, the Tat protein was found to be encoded entirely by the first exon. It is 103 amino acids in size and shares sequence homology with the human immunodeficiency virus (HW) Tat. The BIV tat clone can trans activate the BIV promoter effectively, as measured by the expression of the bacterial chloramphenicol acetyltransferase gene, when transfected into bovine cells. Besides activating the BIV promoter, the BIV Tat can also trans …

Lipoxygenase Inhibitors Shift The Yeast/Mycelium Dimorphism In Ceratocystis Ulmi, Ellen C. Jensen, Clyde Ogg, Kenneth W. Nickerson

Papers in Microbiology

The yeast-mycelium dimorphism in Ceratocystis ulmi, the causative agent of Dutch elm disease, was switched by gossypol, nordihydroguaiaretic acid, and propylgallate. In each case the mycelial form was converted to the yeast form. These compounds are recognized lipoxygenase inhibitors. Inhibitors of cyclooxygenase and thromboxane synthetase did not cause mycelia to shift to the yeast form. We suggest the following two-part hypothesis: (i) that lipoxygenase is a target for antifungal antibiotics and (ii) that many phytoalexins (antimicrobial compounds of plant origin) are targeted toward fungal lipoxygenases. In addition, in a study to determine potential lipoxygenase substrates, a fatty acid analysis …

Characterization Of Restriction-Modification Systems In Klebsiella Pneumoniae, Boontar Valinluck

Loma Linda University Electronic Theses, Dissertations & Projects

Two restriction-modification (R-M) systems KpnAI and KpnBl, found in Klebsiella pneumoniae strains M5a1 and GM236, respectively, have been studied and confirmed to he different from other R-M systems reported in K. pneumoniae. Mutant studies that the KpnAl and KpnBI systems may belong to either a type I or type III systems since approximately equal numbers of r^-m⁺ and r^-m^- mutants were obtained. However, a DNA hybridization study using representative type I and type III probes from E. coli and S. typhimurium failed to show homologies to either KpnAI or KpnBI. The restriction endonuclease …

Kinetic Characterization Of A Recombinant C-Terminal Mutant Of Reverse Transcriptase From The Human Immunodeficiency Virus, Thomas S. Heard

Chemistry & Biochemistry Theses & Dissertations

The human immunodeficiency virus (HIV) reverse transcriptase (RT) (EC 2.7.7.49) is the central replication enzyme for HIV. In general, the kinetic mechanism for this and all other polymerases involves the ordered binding of two substrates: a primer-template (PT) followed by a deoxyribonucleoside triphosphate (dNTP). Previous investigations prompted this research when it was discovered that the substrate dNTP, in absence of PT, could protect a recombinant c-terminal mutant HIV-1 RT from inhibition by pyridoxal-5'-monophosphate (PLP), an active-site dNTP inhibitor. In contrast, the non-mutant recombinant HIV-1 RT required both substrates for protection from PLP inhibition. This investigation sought to determine if this …

Characterization Of Murine Interleukin-4 (Il-4) : Biological Activities And Initial Identification Of Signal Transduction Mechanisms In Il-4-Mediated Macrophage Activation, Henkie Pierre Tan

Loma Linda University Electronic Theses, Dissertations & Projects

IL-4, in the presence of macrophages (MΦs), has previously been demonstrated to be tumoricidal in vitro and in vivo, possibly through MΦ activation. In the current study, the biological activities of murine IL-4 on MΦs, and the initial identification of signal transduction mechanisms in IL-4-mediated MΦ activation were determined. Hamster MΦ were activated with IL-4 to study MΦ tumoricidal activity against hamster pancreatic adenocarcinoma in vivo.Through this initial study, it was observed that murine IL-4 is species specific and incapable of crossing the narrow phylogenetic barrier to hamster and perhaps rat (partially). The effects of murine IL-4 on allogeneic …

Dual Regulation Of Silent And Productive Infection In Monocytes By Distinct Human Immunodeficiency Virus Type 1 Determinants, Howard Gendelman, Peter Westervelt, Timothy Henkel, David B. Trowbridge, Jan Orenstein, John Heuser, Lee Ratner

Nebraska Center for Virology: Faculty Publications

The regulation of human immunodeficiency virus type 1 infection and replication in primary monocytes was investigated by mutagenesis of recombinant proviral clones containing an env determinant required for the infectivity of monocytes. Virus replication was assayed by determination of reverse transcriptase activity in culture fluids and by recovery of virus from monocytes following cocultivation with uninfected peripheral blood mononuclear cells. Three virus replication phenotypes were observed in monocytes: productive infection, silent infection, and no infection. Incorporation of the monocytetropic env determinant in a full-length clone incapable of infection or replication in primary monocytes (no infection) conferred the capacity for highly …

A Modified Scheme For The Isolation And Enumeration Of Bacteria In Municipal Sewage Sludge, Kelly Ball

Masters Theses & Specialist Projects

Because of the potential health hazards associated with the use of sludge for agricultural purposes, Dudley et al (1980) published a scheme for the routine analysis of bacteria in municipal sewage sludge. In this study, the Dudley et al scheme (1980) was modified by updating some of the procedures. Aerobically digested sludge generated by the Bowling Green Wastewater Treatment Plant, Bowling Green, Kentucky, was analyzed using the modified scheme. Sludge samples were collected once every two months over a one-year period from October 1989 to August 1990.

Egg yolk-free tryptose sulfite cycloserine agar in conjunction with the revewrse CAMP test …

Molecular And Cellular Analysis Of Chlamydia Trachomatis: Persistence And Reactivation, Kimberly R. Tau

Electronic Theses and Dissertations

Chlamydia trachomatis (CT) is the most prevalent sexually-transmitted infection in the United States. It has been suggested that CT infections can become latent. This has not been substantiated. CT persistence was examined at the molecular and cellular level in vitro and in vivo. Penicillin treatment of CT in vitro results in abnormal inclusions and reduced recovery of infectious CT. Penicillin did not inhibit initial stages of infection, but did downregulate CT rRNA levels after 25 hours post-inoculation (p.i.). DNA amplification was employed to differentiate between a resolved infection and a persistent one. Utilizing a primer pair that amplified a 144 …

Genetics And Applications Of Nisin Production In Lactococcus Lactis Subsp. Lactis And Conjugal Exchange Of This Trait, Jeffery R. Broadbent

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Chapter I reviews current literature on gene transfer systems in lactic acid bacteria, how genetically altered microorganisms for food are presently regulated, and how nisin is used as a food preservative.

Chapter II investigates previous reports which linked genes for nisin biosynthesis and sucrose utilization (Nip⁺Suc⁺) to plasmid DNA in two well characterized L. lactis subsp. lactis strains. Plasmid curing studies, conjugations, and DNA-DNA hybridizations indicated that these genes were encoded by chromosomal loci in all Nip⁺Suc⁺ strains examined. Similar results were noted in nisin-sucrose transconjugants of L. lactis subsp. cremoris and S. …

Transformation Of A Continuous Rat Embryo Fibroblast Cell Line Requires Three Separate Domains Of Simian Virus 40 Large T Antigen., Jiyue Zhu, Philip W. Rice, Lisa Gorsch, Marina Abate, Charles N. Cole

Dartmouth Scholarship

Mouse C3H 10T1/2 cells and the established rat embryo fibroblast cell line REF-52 are two cell lines widely used in studies of viral transformation. Studies have shown that transformation of 10T1/2 cells requires only the amino-terminal 121 amino acids of simian virus 40 (SV40) large T antigen, while transformation of REF-52 cells requires considerably more of large T antigen, extending from near the N terminus to beyond residue 600. The ability of a large set of linker insertion, small deletion, and point mutants of SV40 T antigen to transform these two cell lines and to bind p105Rb was determined. Transformation …

Cytolytic T Lymphocytes Specific For Tumors And Infected Cells From Mice With A Retrovirus-Induced Immunodeficiency Syndrome., Jennifer G. Erbe, Kathy A. Green, Karen M. Crassi, Herbert C. Morse, W R. Green

Dartmouth Scholarship

LP-BM5 retrovirus complex-infected C57BL/6 mice develop immunodeficiency, somewhat analogous to AIDS, termed murine AIDS (MAIDS). After secondary stimulation with syngeneic B-cell lymphomas from LP-BM5-infected mice, C57BL/6 mice produced vigorous CD8+ cytotoxic T lymphocytes specific for MAIDS-associated tumors. An anti-LP-BM5 specificity was suggested because spleen and lymph node cells from LP-BM5-infected mice served as target cells in competition assays, and cells from LP-BM5, but not ecotropic, virus-infected mice functioned as secondary in vitro stimulators to generate cytotoxic T lymphocytes to MAIDS tumors.

Identification And Characterization Of A Human Herpesvirus 6 Gene Segment That Trans Activates The Human Immunodeficiency Virus Type 1 Promoter, Yunqi Geng, Bala Chandran, Steven Josephs, Charles Wood

Nebraska Center for Virology: Faculty Publications

Human herpesvirus 6 (HHV-6) is a lymphotropic herpesvirus, and in vitro, HHV-6 can productively infect many of the same cell types as can human immunodeficiency virus (HIV). Coinfection by both viruses in vitro can lead to both activation of the HIV promoter and acceleration of cytopathic effects. We have previously demonstrated that a large, 22.25-kb cloned HHV-6 fragment, pZVB70, can trans activate HIV promoter expression in vitro. In this study, we show that the pZVB70 fragment can trans activate the HIV promoter in human T-cell lines as well as in the monkey kidney cell line CV-1. The pZVB70 insert was …

The Expression And Regulation Of The Hsdk Genes Of Escherichia Coli K-12, Ainu Prakash

Loma Linda University Electronic Theses, Dissertations & Projects

The DNA restriction and modification of (R-M) genes in bacteria play a defensive role in the organism, offering protection to the host from invaders such as bacteriophages. The expression of these genes in E. coli K-12 has no previously been studied due to the complexity of EcoK R-M enzymes. The use of lacZ gene fusion techniques allowed studies of the expression of the hsdK genes for the first time. Operon fusions of Mu(lac) to the hsdK genes show that the two hsdK promoters, P_res and Pmod, are weak (50 Miller units) and that both operate …

The Expression And Regulation Of The Hsdk Genes Of Escherichia Coli K-12, Ainu Parkash

Loma Linda University Electronic Theses, Dissertations & Projects

The DNA restriction and modification (R-M) genes in bacteria play a defensive role in the organism, offering protection to the host from invaders such as bacteriophages. The expression of these genes in E. coli K-12 had not previously been studied due to the complexity of the EcoK R-M enzymes. The use of lacZ gene fusion techniques allowed studies of the expression of the hsdK genes for the first time. Operon fusions of Mu(/ac) to the hsdK genes show that the two hsdK promoters, p _res and p _mod, are weak (50 Miller units) and that …

Cyanonews (Vol. 8, No. 1, February 1992), 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.

Cyanonews (Vol. 8, No. 2, July 1992), 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.

Generation Of Cross-Reactive Monoclonal Anti-Streptococcal Cell Membrane Antibodies: The Evolution Of A Murine Model For Goodpasture's Syndrome, Edward J. Fitzsimons

Dissertations

No abstract provided.

Studies Of The Virion Host Shutoff Function Of Herpes Simplex Virus, Annette Schmidt Pak

Dissertations

No abstract provided.

The Inhibitory Effects Of The Extracts Of Zingiber Plants On The Adsorption, Growth, And Replication Of Phage Lpp-1 In Cyanobacterium, Ebby Paul Jido

Master's Theses

No abstract provided.

The Morphology, Physiology, And Fine Structure Of A Toluene-Oxidizing Strain Of Pseudomonas Putida, Barry Clayton Anderson

Dissertations and Theses

The role of microorganisms in the degradation of xenobiotics in the environment is well established. Bacteria from the genus Pseudomonas are particularly well adapted to the degradation of hydrocarbons, aromatics, and numerous other natural and introduced substrates. We have isolated a strain of Pseudomonas putida, designated PC2P15, that uses toluene, phenol, benzene, and a number of other substrates as its sole sources of carbon and energy.

Altered Expression Of Adenovirus 12 Dna-Binding Protein But Not Dna Polymerase During Abortive Infection Of Hamster Cells, Lynne A. Lucher, Benjawan Khuntirat, Jiansheng Zhao, Peter C. Angeletti

Nebraska Center for Virology: Faculty Publications

Replication of human adenovirus type 12 DNA is blocked in abortively infected baby hamster kidney cells. The activity and accumulation of adenovirus 12 DNA polymerase is equivalent in infected hamster and human cell extracts. However, the accumulation of adenovirus type 12 DNA-binding protein is approximately 120-fold lower in extracts from infected hamster cells when compared to infected permissive human cells. This difference in accumulation is not because of replication of viral DNA during productive infection, since this difference is observed in the presence of hydroxyurea. The DNA-binding protein from infected hamster cells retains the ability to bind denatured DNA-cellulose. An …

Characterization Of Human Cell Lines Transformed By Hsv-2 And Hpv-16 Or Hpv-18, Kavita Rao Dhanwada

Dissertations

No abstract provided.