Microbiology Commons^™

Homologous Strand Exchange And Dna Helicase Activities In Plant Mitochondria, Daqing Song

Theses and Dissertations

Homologous recombination is critical for generating genetic variation in living organisms by exchange and rearrangement of DNA. Most of our knowledge about homologous recombination is limited to processes in bacteria or in eukaryotic nuclei. In E. coli, homologous recombination is dependent on the RecA protein. Higher plant chloroplasts have RecA-like strand exchange activity. However, little is known about these mechanisms in higher plant mitochondria. I have detected a RecA-like strand exchange activity in soybean mitochondria. This activity forms joint molecules in the presence of ATP, Mg2+, and homologous DNA substrates. In addition, the E. coli single-stranded DNA binding (SSB) protein …

Investigation Of The Mechanisms Of Ozone-Mediated Viral Inactivation, Seiga Ohmine

Theses and Dissertations

Previous studies have established that ozone-oxygen mixtures can be used to inactivate a variety of microorganisms including bacteria, fungi and viruses. Ozone is a potent reactive oxygen species (ROS) that rapidly decays into a variety of additional short half-life ROS which have been shown to cause oxidative damage to biological molecules. I hypothesize that controlled ozone exposure and the subsequent generation of additional ROS would reduce viral infectivity by lipid and/or protein peroxidation. A proprietary ozone-oxygen delivery system was used to inactivate a series of enveloped [herpes simplex virus type-1 strain McIntyre (HSV-1), vaccinia strain Elstree (VAC), vesicular stomatitis virus …

Crustacean Phylogenetic Systematics And Opsin Evolution, Megan L. Porter

Theses and Dissertations

Composed of a chromophore bound to an integral membrane protein (opsin), visual pigments are phenotypically characterized by the wavelength of maximal absorption (λmax). The underlying molecular mechanism controlling λmax is the interaction between the opsin amino acid sequence and the chromophore. While a plethora of studies have looked at structure/function relationships in vertebrate opsins, fewer studies have investigated similar issues in invertebrates. Furthermore, those few studies undertaken in invertebrate systems suggest different mechanisms of spectral tuning and photoactivation compared to vertebrate systems. This dissertation research is focused on expanding our knowledge of opsin evolution in invertebrate systems, particularly from non-insect …

Assessment Of Cell Death Parameters In Bovine Parvovirus-Infected Ebtr Cells, Lubna Salah Eldin Abdel Latif

Theses and Dissertations

Bovine parvovirus (BPV) is a helper-independent parvovirus. It has a small icosahedral capsid with a single stranded DNA genome. It is a highly stable virus with a narrow host range. It causes acute gastroenteritis in calves. It is considered to be a cytolytic virus because it kills the host cells. However, the mechanism by which the virus causes cell death is not known. The work described in this thesis assessed different parameters of cell death in BPV infected embryonic bovine tracheal (EBTr) cells. There are several ways for viruses to induce cell death. Viruses can induce apoptosis in the infected …

Identification Of Proteins Involved In Chloroplast Dna Replication, Matthew G. Lassen

Theses and Dissertations

Chapter 1

Chloroplast nucleoids (ct-nucleoids) are DNA/protein complexes involved in compacting the chloroplast genome, and may play a role in regulating DNA replication. Ct-nucleoids were isolated from young soybean plants and separated by 2-D gel electrophoresis. Gel spots were excised and analyzed by MALDI-ToF mass spectrometry, resulting in several protein identifications. The proteins identified all have functions unrelated to DNA replication. While some of these proteins may be due to contamination, it is possible that some of these proteins are dual-functional, playing direct roles in the regulation of DNA replication.

Chapter 2

A 28 kDa soybean protein was isolated by …

Investigating The Mechanism Of Acoustically Activated Uptake Of Drugs From Pluronic Micelles, Ghaleb A. Husseini, Christopher M. Runyan, William G. Pitt

Faculty Publications

This paper examines the mechanism of ultrasonic enhanced drug delivery from Pluronic micelles. In previous publications by our group, fluorescently labeled Pluronic was shown to penetrate HL-60 cells with and without the action of ultrasound, while drug uptake was increased with the application of ultrasound. Methods In this study, the amount of uptake of two fluorescent probes, Lysosensor Green (a pH-sensitive probe) and Cell Tracker Orange CMTMR (a pH-independent probe), was measured in HL-60 and HeLa cells. Results: The results of our experiments show that the increase in drug accumulation in the cells as a result of ultrasonication is not …

The Mycobactericidal Efficacy Of Orthophthalaldehyde And The Comparative Resistances Of Mycobacterium Bovis, Mycobacterium Terrae, And Mycobacterium Chelonae, Richard A. Robison, Adam W. Gregory, G. Bruce Schaalje, Jonathan D. Smart

Faculty Publications

Objectives: To assess the mycobactericidal efficacy of an agent relatively new to disinfection, ortho-phthalaldehyde (OPA) and to compare the resistances of three Mycobacterium species. Mycobacterium bovis (strain BCG) was compared with Mycobacterium chelonae and Mycobacterium terrae to investigate the feasibility of using either of the latter two species in tuberculocidal testing. M chelonae (a rapid grower) and M terrae (an intermediate grower) both grow faster and are less virulent than M bovis (a slow grower).

Determination Of The Microbiological Load Of The Principal Meat Products Sold In The Markets Of Riobamba, Miguel Angel Castillo Palacios

Theses and Dissertations

This investigation was done with the objective to determine the microbiological load of the main meat products such as: beef, chicken meat, sausage, and viena sausage which are sold in the Riobamba city markets. This investigation was carried out in the Microbiological Laboratory Livestock Science faculty of the Polytechnical Superior school. Specific chemical products were used to determine mesofilas (37 degrees C), xicrofilas (5 degrees C), and termofilas bacteria which did not develop at 45 degrees C, however exicrofilas and mesofilas bacteria were found in every market and meat product in this study. The meat product hygiene is the same …

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 …

Fixation Of Dormant Tilletia Teliospores For Thin Sectioning, John Scott Gardner

Theses and Dissertations

Dormant Tilletia caries teliospores in fixative solution or distilled water were frozen onto specimen chucks of an FTS Sorvall- Christensen frozen thin sectioner and cut or fractured at various temperatures (-20 to -75 C) and thickness settings (10, 15, 20, and 25 um). Cytoplasm of dormant spores was well preserved and organelles were found to differ from those of germinated spores in morphology. Irregular electron dense and electron opaque areas of lipid bodies were sometimes evident in dormant and germinating Tilletia caries teliospores. When dormant teliospores were sectioned in buffered fixative, lipids had an appearance similar to lipids in thin …

Light And Electron Microscopy Investigation Of Developing Wheat Caryopses Infected By Tilletia, Melvin Douglas Grove

Theses and Dissertations

Caryopses of wheat were studied during infection by Tilletia caries and T. controversa. Initially the pathogens penetrated embryos of the host. After the embryo tissue was consumed by the fungi, endosperm tissue was penetrated and consumed. Initial penetration of endosperm tissue was in localized areas. During infection the fungus mycelium spread intercellularly, but occasionally was seen intracellularly. As the host tissue was consumed teliospores were formed. At maturity a host cell layer 4-6 cells thick remained which retained the mature teliospores. Histochemical studies indicated that carbohydrates and lipids of the host disappeared soon after invasion by the pathogens. Nuclei and …

Lipids Of Fungal Spores, Identification And Metabolism, Jim L. Bushnell

Theses and Dissertations

The lipids of the spores of the Basidiomycetes: Ustilago bullata, Lycoperdon perlatum and Calvatia gigantea were investigated. The spores of U. bullata were found to have hydrocarbons ranging from C_9 to C_24, methyl esters of fatty acids ranging from C_14 to C_24, and free fatty acids from C_14 to C_24. The spores of L. perlatum were found to have few hydrocarbons (C_22 being the predominent one); no methyl esters were detected and the fatty acids were from C_15 to C_18. Long chain aldehydes (C_30) were also detected in low concentration. At the ultrastructural level the Lycoperdon spores were found to …

A Pectin Histochemical Study Of The Host Pathogen Relationship Between Pyrenochaeta Terrestris And Allium Cepa, Leroy Richard Cobia

Theses and Dissertations

The involvement of pectin and pectinases in the host pathogen interaction of P. terrestris and Allium cepa were investigated by use of pectin histochemical stains at the electron microscope level. Several different pectin histochemical stains were used, but only two (the hydroxylamine reaction, and the pectin stain developed in this study) gave reliable results. It was observed that by the time the fungus has reached the host cell wall pectinesterase and endoplygalacturonase have fully removed the pectin from the host cell wall. When this has occurred, cellulases are released which continue to degrade the host cell wall. Electron transparent areas …

Ultrastructural And Histochemical Investigations Of Ipomoea Batatus Lam. Infected By Rhizopus Stolonifer (Fr.) Lind, Kendall O. Smith

Theses and Dissertations

The ultrastructural aspects of Rhizopus stolonifer (Fr.) Lind. Infection in Ipomoea batatus Lam. Roots and the histochemistry of cell walls affected by enzymes secreted by the fungus were investigated. Specimens were prepared for viewing in the electron microscope by thin-sectioning techniques. Degradation of cellular membreanes and host tissues in advance of the fungus was evident. Breakdown of the middle lamella was detected by special histochemical stains for pectin. Breakdown occurred in the following was: (1) maceration of the middle lamella before maceration of the cell wall, (2) simultaneous degradation of both the middle lamella and the cell wall, (3) maceration …

Taxonomy And Ecology Of Fungi Imperfecti From Four Locations In Utah Lake, Utah Co., Utah, Laird Max Hartman

Theses and Dissertations

Fungi imperfecti were cultured from water and bottom sediment samples collected at four locations of Utah Lake. These study sites included: (a) The mouth of Provo River, the largest fresh-water tributary entering Utah Lake, (b) Mud Lake, a large shallow area known for its high nitrogen content, (c) the entrance of the Spanish Fork River into the lake, a large fresh-water tributary containing wastes from industry and agricultural enterprises, (d) Jordan River, the only natural outlet of Utah Lake. One hundred and thirty-eight species of fungi imperfecti were identified. A total of 89 species were isolated from the Spanish Fork …

Ultrastructural Investigations Of Tilletia Caries Teliospores, James Vincent Allen

Theses and Dissertations

The purpose of this study was to investigate the ultrastructure of Tilletia caries teliospores. Specimens were prepared for viewing in the electron microscope by freeze-etching and thin-sectioning techniques. Thin-sectioning techniques gave excellent results with the teliospore walls and the lipid bodies within the teliospore but failed to adequately fix the membranes and internal organelle systems. Micrographs of Tilletia caries teliospores prepared using thin-sectioning show three major wall layers and two partition wall layers and abundant lipid bodies. The freeze-etch method of spore preparation proved superior to the thin-sectioning used in this study to reveal the internal organelle systems of the …

Surface Characteristics Of Conidia From Monosporous Cultures Of Penicillium Digitatum And Aspergillus Nidulans Var. Echinulatus, Raymond Kunito Fuji

Theses and Dissertations

The purpose of this investigation was to evaluate the possible taxonomic significance of the "rodlet" patterns and spore wall configurations of conidia from monosporous cultures of Penicillium digitatum Saccardo and Aspergillus nidulans Eidam var. echinulatus Fennell & Raper. Freeze-etching the conidiospores from single spore isolates of these fungi revealed that spore wall patterns and configurations vary much too greatly to be of taxonomic importance on the strain and subspecies level. Environmental factors and genetic influences are discussed as possible mechanisms causing the variations of the spore wall configurations. A membrane-like structure that covers the "rodlet" patterns and which hinders spore …

The Identification Of A Germination Factor For Basidiospores Of Psilocybe Mutans, Neal K. Van Alfen

Theses and Dissertations

Basidiospores of the Basidiomycete Psilocybe mutans have been found to germinate only in the presence of water extracts of animal dung. The chemical nature of the factor present in the dung that induces germination is not known, nor has it ever been isolated· Experiments showed that extracts of bile salts cause the basidiospores to germinate, indicating that since bile salts are found in dung, they may be the factor which stimulates the spores to germinate. Investigations of the properties of the factor in dung show that the factor has solubility properties that are similar to those of the bile acids. …

A Comparative Survey Of Soil Microfungi From Three Vegetation Types In Cedar Valley, Utah, Brent T. Wahlquist

Theses and Dissertations

Microfungi were isolated from soil samples by the soil plate method. Soil samples were collected at depths of 0-1", 1-4", and 4-8" both between and beneath the canopy of the dominant vegetation in stands of greasewood, sagebrush, and pinyon-juniper. Salinity, pH, and percent organic matter were measured for each soil sample. A total of 148 strains of fungi representing 141 species and 46 genera were isolated and identified from these alkaline soils, Few strains, including some Aspergilli, occurred only in the more saline greasewood soils, while many strains, including several Penicillia, occurred in both sagebrush and piny-on-juniper soils but were …

A Study Of Aquatic Fungi In Powell's Slough, Chao-Chih Hsiao

Theses and Dissertations

Aquatic fungi in-Powell's Slough were.studied in 1967 & 1968. Collections were made and water temperature, oxygen content & pH values were measured at weekly intervals. For collections, wire baskets containing substrata were submerged in water for one month. After collecting, substrata were brought to the laboratory. Identification was based on the keys of Sparrow, 1960. Aquatic fungi identified included seven orders, nine families, fifteen genera, and thirty species, from thirty-three collections of fifteen types of substrata. The substrata used in this study were: (i) fruits: apples, rose hips, plums, pears, haws; (ii) twigs: poplar, weeping willow, river birch, weeping white …

Ultrastructural Investigations Of Powdery Mildew Of Rose Caused By Sphaerotheca Pannosa (Wallr.) Lev, Ani Clipper Watene

Theses and Dissertations

The purpose of this study was to evaluate the ultrastructural aspects of the host-pathogen relationship between the fungus Sphaerotheca pannosa (Wallr.) Lev. and a susceptible horticultural variety of floribunda rose "Eutin". Attention was given to the penetration of hyphal tubes, and their subsequent development into: haustorial elements in epidermal cells of rose. In addition, changes in the morphology of infected epidermal cells were described. Thin sections of rose leaves infected with S. pannosa were examined in a Hitachi electron microscope, model HS-7, after glutaraldehyde-acrolein fixation, OsO4-uranyl acetate staining, and embedding in Epon plastic. The components of S. pannosa haustoria consisted …

The Taxonomy And Ecology Of The Fleshy Fungus Flora Of The Snowbanks In The Mirror Lake Region Of The Uinta Mountains, Mary Virginia Charlton Dublin

Theses and Dissertations

The ecology and taxonomy of the snowbank fleshy fungi in the vicinity of Mirror Lake, Uinta Mountains, Utah were investigated during 1963, 1964, and 1965. A total of 59 speciaes, representing the Agaricales, Polyporales, Thelephorales, Gastromycestes, Myxomycetes, Dacrymycetales, and Ascomycetes, were found associated with the snowbanks. Four of these species (Geupiniopsis alpinus, Polyporus alboluteus, Polyporus leucospongia and Sterile myclium I) have presence percentages of 100% and three (Stereum Rugisporum, Dasyscypha arida and Herpotichia nigra) had presence percentages of 90%. The lignicolous fungi were found to be more frequent around the snowbanks than either the terrestrial or coprophilous fungi. No fleshy …

Aquatic Phycomycetes Of Lily Lake, Hugh Macmillan Rooney

Theses and Dissertations

Lily Lake, a subalpine lake in the Wasatch National Forest Tl5, R9E, S31, of the Uinta Mountain Region, Utah, is located about one-half mile west of Trial Lake at an elevation of 10,000 feet. This Lake, which is one of the acidic, cold, lentic bogs characteristic of this area, has been selected for a taxonomic and seasonal distribution study of acquatic phycomycetes. This study is a beginning to our knowledge of the role of the fungi in the hydrobiology of Lily Lake and will supply the first information on record of the water molds of this area. The study identifies …

A Phytosociological Study Of Coprophilous Ascomycete And Basidiomycete Communities From Santaquin Canyon, Utah, A. Clyde Blauer

Theses and Dissertations

Numerous reports have been published on the taxonomy and distribution of the coprophilous Ascomycetes and Basidiomycetes. No known quantitative work has been done, however, on the succession and structure of the communities formed by these higher fungi. This research was undertaken to study those two phases of the ascomycete and basidiomycete communities which grow and fruit on cow dung collected from Santaquin Canyon, Utah.

A Study Of Albinism, And Some Mating Reactions In Psilocybe Mutans, Henry L. Curtis

Theses and Dissertations

In recent taxonomic works albinism is not generally recognized as being present in the Agaricales. This study was made to find how albinism was inherited in Psilocybe mutans McKnight. Cultures of P. mutans were incubated in a constant temperature room at 20-22°C. With artificial lighting at 150 foot candles for 16 hours per day and on a laboratory bench at a comparable temperature with diffuse natural light of a lesser intensity. Numerous fruit-bodies were obtained from cultures which grew on substrates containing hot water extracts of rabbit fecal pellets and from cultures grown on substates containing no fecal extracts. In …

A Study Of The Coprophilous Ascomycetes Of Utah, David L. Hanks

Theses and Dissertations

Specimens of animal dung were collected from various areas of the state of Utah. These were cultured by placing a few small pieces in a culture dish over moistened sphagnum moss and filter paper. The cultures were observed periodically and specimens were studied as they matured upon the substratum. A total of eighty-four species representing three orders and fifteen genera are reported. Of these, nine species have not previously been described. Included is one species, Tripterospora erostrata, from the order Plectascales of the Series Plectomyceteae. Cited from the order Sphaeriales of the Series Pyrenomyceteae are forty-nine species as follow: Coniochaeta, …

A Study Of The Effects Of Different Substrates On Growth And Reproduction In Certain Coprophilic Agaricaceae, Raymond C. Brown

Theses and Dissertations

Psilocybe mutans sp. nov. had ceased fruiting consistently in artificial culture several years prior to the initiation of this study. In the couse of this study fruiting bodies were produced on a number of different substrates. All cultures were inoculated by mycelial transfer or by spraying with a suspension of pre-germinated spores. All cultrues were incubated for one to two weeks in a constant-temperature room at 70°F. on a shelf fourteen inches below a fluorescent lighting fixture. Lighting was continuous with an intensity at shelf level of approximately 3,000 foot-candles. Fruiting on any particular substrate was improved if the substrate …

A Study Of Physoderma On Three Species Of Portulacaceae, David L. Mumford

Theses and Dissertations

Three species of the Portulacaceae each infected by a Physoderma parasite were collected at several locations in Utah. The hosts have been identified as Claytonia lanceolata Pursh., Oreobroma pygmaeum (A. Gray) Howell, and Erocallis triphylla (S. Wats.) Rydb. Since our present knowledge of Physoderma on members of the Portulacaceae is meager, it seemed desirable to learn as much as possible about the parasite, its hosts, and the relationship between parasite and host. Plants of all three hosts activated from perennating organs were grown for extended periods of time under uniform conditions. Cold treatments were most successful in activating host perennating …

A Study Of The Fleshy Fungi Of Utah, Kent Howell Mcknight

Theses and Dissertations

It is the purpose of this study to further the ends of Mycology by presenting the fleshy fungi which are known to grow in Utah. The term fleshy fungi as used here shall include those Ascomycetes and Basidiomycetes which produce large or otherwise conspicuous sporocarps and their closely related forms. This includes portions of the sub-classes Pyrenomycetes and Discomycetes of the Ascomycetes; and portions of the Heterobasidiao and Eubasidiae of the Basidiomycetes (4). The sporocarps may be fleshy, woody, papery, leathery, carbonous or waxy in texture. This would exclude the Myxomycetes. However, since there have been no extensive studies of …