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 Department: Department of Biology
 Collection: UNT Theses and Dissertations
Assimilation of Inorganic Nitrogen by Aquatic Actinomycetes
It was the purpose of this investigation to present laboratory data concerning the assimilation of inorganic nitrogen by the aquatic actinomycetes. The strains of aquatic actinomycetes under consideration represented a cross section of those currently under culture at North Texas State University. digital.library.unt.edu/ark:/67531/metadc108150/
Assimilation of Organic Carbon by Aquatic Actinomycetes
There were two purposes of this investigation: the first was to develop a method for studying spore germination, hyphal growth and mycelial development of the aquatic actinomycetes under the microscope so that the life cycle of this organism could be continuously followed. The second purpose was to determine the rate of carbon utilization from various types of nutritional sources, and to correlate this with the colony development and spore formation. digital.library.unt.edu/ark:/67531/metadc163851/
The Autecology of Celtis Laevigata in Flood Plain Forests of Denton County, Texas
This thesis describes the present nature of one facet of some of the flood plain forest stands in Denton County, Texas. The specific purpose was to demonstrate the presence or absence of difference between the Celtis laevigata (commonly known as the hackberry, southern hackberry or sugarberry) populations in stands on Denton Creek and Elm Fork of the Trinity River. digital.library.unt.edu/ark:/67531/metadc163960/
Autoimmunity of Periodontitis
The purpose of this investigation is to determine if auto-antibodies are demonstrable in inflammatory periodontal disease using methods other than those of Novotny. digital.library.unt.edu/ark:/67531/metadc108240/
Bacterial Antibiotic Properties of the Oleoresins of Thirty Summer Flowering Spermatophytes
The purpose of this investigation is to add to the present day knowledge concerning the presence of antibiotics in additional members of the spermatophyte group of plants. digital.library.unt.edu/ark:/67531/metadc83741/
A Bacterial Spectrum of Antibiotic "S"
This thesis is an investigation of Antibiotic "S" with the purpose of determining which organisms it has a marked effect on, the amount required to cause inhibition, its action in blood, and its therapeutic effect and toxicity in laboratory animals. digital.library.unt.edu/ark:/67531/metadc83589/
Bacterial Survey of Representative Denton County Wells with Special Reference to Sanitation
This thesis aimed to study the seventy-two representative wells of Denton County and to determine the possibilities of infection with typhoid organism. The sanitary survey and the test for Colon-Aerogenes bacteria show that 55% of the 72 wells studied are unsanitary, 27% are sanitary, and 18% are doubtful. digital.library.unt.edu/ark:/67531/metadc29851/
Bacterial Survey of Representative Wells of Canyon, Texas, with Special Emphasis on Sanitation
The problem of this thesis consists of a bacterial analysis of twenty-five representative wells within a radius of thirty miles of Canyon, Texas. An attempt has been made to determine the possible presence of the typhoid organism in these wells. digital.library.unt.edu/ark:/67531/metadc75367/
Bacterial Survey of the Sources of Drinking Water of Trinidad, Texas, with Special Reference to Sanitation
A bacterial analysis of the water from thirty-six sources of consumption by the white population of Trinidad, Henderson County, Texas, was made to determine the potability of each of these in regard to infection from typhoid or related organisms. digital.library.unt.edu/ark:/67531/metadc75382/
Bacterial Utilization of Volatile Substances Produced by Streptomyces Lavendulae
The purpose of this investigation is to attempt to learn something of the biochemical ecology of volatile substances produced by actinomycetes. digital.library.unt.edu/ark:/67531/metadc130845/
A Bacteriological Survey of a Freshwater Reservoir
In this study organisms that can be subcultured from lake water, using a prescribed procedure, limit, to an extent, the population, or portions of the population, that can be monitored. In essence, what is taking place is that a set of conditions is set forth and a study is made of the bacteria that will grow under these prescribed conditions. digital.library.unt.edu/ark:/67531/metadc130924/
Bentric Algae of Selected Thermal Springs of Yellowstone National Park
The purpose of this investigation was to characterize the population dynamics of the benthos of selected pristine thermal springs. digital.library.unt.edu/ark:/67531/metadc130511/
A Bio-Chemical Comparative Study of the Plankton in Lake Dallas and Pecan Creek
The purpose of this investigation is to compare the dissolved and suspended organic material in Lake Dallas to that coming into the lake through Pecan Creek. digital.library.unt.edu/ark:/67531/metadc75591/
The Biological Elimination of Phenols in the Effluent of a Wood Preserving Plant
The removal of phenols from the waste waters of wood preserving plants has always presented problems. The purpose of this paper is to investigate the possibility of employing a biological system to reduce the phenol content of effluent from these plants. digital.library.unt.edu/ark:/67531/metadc131445/
Biological Indices of Stream Pollution
A thorough biological survey and evaluation is a lengthy and expensive project. The number of technically trained persons required prevent its use by most public agencies. Since public health departments are the groups most frequently concerned with measuring the effects of pollution in streams, a need exists for a simplified method of sanitary survey. Recognizing this need, the Texas Heal Department assigned the writer the problem of devising a method of survey which would require a field party of two and could be conducted entirely from a mobile field laboratory. digital.library.unt.edu/ark:/67531/metadc130298/
Capillary Permeability to Macromolecules at Normal and Hypobaric Pressure
The purpose of this investigation was to study the effects of decreased barometric pressure on the transcapillary movement of molecules by monitoring the macromolecular capillary permeability with lymph derived primarily from the hepatic and gastrointestinal regions of the dog. digital.library.unt.edu/ark:/67531/metadc131162/
Capillary Permeability to Narrow-Range Macromolecular Dextrans at Normal and Hypobaric Pressures
In view of its varied concepts and interpretations, and because of the discrepancies produced by the previous utilization of polydispersed dextrans, a study using extremely narrow-range molecular weight dextran fractions was initiated to reevaluate and consolidate some of the aspects of capillary permeability. A portion of the study was performed under decreased barometric pressure in order to clarify further some of the mechanisms involved in particulate transfer across the capillary endothelial membranes. Gel filtration procedures augmented the study as an assessment of the polydispersity effects of the dextrans employed. digital.library.unt.edu/ark:/67531/metadc164035/
Changes in Gene Expression Levels of the Ecf Sigma Factor Bov1605 Under Ph Shift and Oxidative Stress in the Sheep Pathogen Brucella Ovis
Brucella ovis is a sexually transmitted, facultatively anaerobic, intracellular bacterial pathogen of sheep (Ovis aries) and red deer (Cervus elaphus). Brucella spp. infect primarily by penetrating the mucosa and are phagocytized by host macrophages, where survival and replication occurs. At least in some species, it has been shown that entry into stationary phase is necessary for successful infection. Brucella, like other alphaproteobacteria, lack the canonical stationary phase sigma factor ?s. Research on diverse members of this large phylogenetic group indicate the widespread presence of a conserved four-gene set including an alternative ECF sigma factor, an anti-sigma factor, a response regulator (RR), and a histidine kinase (HK). The first description of the system was made in Methylobacterium extorquens where the RR, named PhyR, was found to regulate the sigma factor activity by sequestering the anti-sigma factor in a process termed "sigma factor mimicry." These systems have been associated with various types of extracellular stress responses in a number of environmental bacteria. I hypothesized that homologous genetic sequences (Bov_1604-1607), which are similarly found among all Brucella species, may regulate survival functions during pathogenesis. To further explore the involvement of this system to conditions analogous to those occurring during infection, pure cultures of B. ovis cells were subjected to environments of pH (5 and 7) for 15, 30, and 45 minutes and oxidative (50mM H2O2) stress, or Spermine NONOate for 60 minutes. RNA was extracted and converted to cDNA andchanges in transcript levels of the sigma factor Bov1605 were measured using qPCR. Preliminary results indicate that under the exposure to Spermine NONOate there was little change in expression, but under oxidative stress expression of the sigma factor Bov1605 was 4.68-fold higher than that expressed under normal conditions. These results suggest that the sigma factor Bov1605 may be involved in oxidative stress defense during infection. Under acid stress (pH5), Bov1605 was found to be upregulated at 15 and 30 minutes, but after 45 and 60 minutes the time decreased. digital.library.unt.edu/ark:/67531/metadc177218/
Changes which Occur in Components C'3 and C'4 in Guinea Pig Complement after Injection of an Antigen
This thesis describes an experiment involving guinea pigs' blood and the changes that occurred in the serum with the injection of an antigen. The serum was analyzed in complement titration tests. digital.library.unt.edu/ark:/67531/metadc107964/
Characterization of Moraxella bovis Aspartate Transcarbamoylase
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Aspartate transcarbamoylase (ATCase) catalyzes the first committed step in the pyrimidine biosynthetic pathway. Bacterial ATCases have been divided into three classes, class A, B, and C, based on their molecular weight, holoenzyme architecture, and enzyme kinetics. Moraxella bovis is a fastidious organism, the etiologic agent of infectious bovine keratoconjunctivitis (IBK). The M. bovis ATCase was purified and characterized for the first time. It is a class A enzyme with a molecular mass of 480 to 520 kDa. It has a pH optimum of 9.5 and is stable at high temperatures. The ATCase holoenzyme is inhibited by CTP > ATP > UTP. The Km for aspartate is 1.8 mM and the Vmax 1.04 µmol per min, where the Km for carbamoylphosphate is 1.05 mM and the Vmax 1.74 µmol per min. digital.library.unt.edu/ark:/67531/metadc3012/
Characterization of the aspartate transcarbamoylase (ATC2) that is found in the pyrBC’ complex of Bordetella pertussis
An aspartate transcarbamoylase (ATCase) gene from Bordetella pertussis was amplified by PCR and ligated into pT-ADV for expression in Escherichia coli. This particular ATCase (pyrB) was an inactive gene found adjacent to an inactive dihydroorotase (DHOase) gene (pyrC'). This experiment was undertaken to determine whether this pyrB gene was capable of expression alone or if it was capable of expression only when cotransformed with a functional pyrC'. When transformed into E. coli TB2 pyrB-, the gene did not produce any ATCase activity. The gene was then co-transformed into E. coli TB2 pyrB- along with a plasmid containing the pyrC' gene from Pseudomonas aeruginosa and assayed for ATCase activity. Negative results were again recorded. digital.library.unt.edu/ark:/67531/metadc3057/
Chemical and Physiological Properties of an Antibiotic Produced by a Variant of the Penicillium Notatum-Chrysogenum Group
The present study of the production and properties of an antibiotic was undertaken in the hope that some useful information could be contributed to a long-range investigation program being carried on at North Texas State Teachers College. This program is concerned with the production of a useful antibiotic from a variant of the Penicillium notatum-chysogenum group of molds. digital.library.unt.edu/ark:/67531/metadc70386/
The Chemical Compounds Produced by Actinomycetes and Their Relation to Tastes and Odors in a Water Supply
The purpose of this problem was to determine the cause of tastes and odors in the Breckenridge water supply and to isolate and culture the organisms responsible for the offensive chemicals. digital.library.unt.edu/ark:/67531/metadc97004/
Chronic Acceleration and Osteogenesis
The effect of excess gravity on bone-forming elements of the growing perichondrial shaft of embryonic chicks was investigated through the use of the transmission electron microscope and various cytochemical techniques. digital.library.unt.edu/ark:/67531/metadc131630/
Colonial Variations of a Mucoid Strain of Staphylococcus Aureus
It was the purpose of the present investigation to demonstrate the selection of a variant of one strain of Staphylococcus aureus by altering certain environmental factors, and to study that variant as to biochemical activities and capsule formation. digital.library.unt.edu/ark:/67531/metadc108202/
A Comparative Study of Egg Media in the Primary Isolation of Mycobacterium Tuberculosis
The primary purpose of this investigation is not only to improve the present technique of culture of Mycobacterium tuberculosis, but also to make a comparative study of the media use, namely, Veterans Administration modification of Trudeau's medium, Lowenstein's egg medium, and that developed by the author, in order to find which, if any, of these will most easily and effectively meet the needs of the hospital laboratory. digital.library.unt.edu/ark:/67531/metadc83506/
A Comparative Study of Four Genealogies to Determine Predisposition to Cancer
This study was made in an effort first, to determine the mode of transmission of the inheritance of a predisposition to cancer as revealed through the analyses of four separate human genealogies, and second, to make a comparative study of the genealogies to determine whether the mode of transmission is the same. digital.library.unt.edu/ark:/67531/metadc75283/
A Comparative Study of the Bottom Fauna of four Texas Lakes
This thesis attempted to study the bottom productivity both qualitatively and quantitatively with reference to the distribution of bonthos. The study of the bottom fauna in large reservior lakes is a relatively new field. This work will give more information on an unknown field than previously existed, although its scope is not intend to be exhaustive. digital.library.unt.edu/ark:/67531/metadc29918/
A Comparative Study of the D Cells of Certain Mammalian Islets of Langerhans
The purpose of this study is to describe and compare the D cells of the islets of Langerhans in six different species of mammals. digital.library.unt.edu/ark:/67531/metadc163839/
Comparative Ultrastructural Study between Young and Adult forms of Trypanosoma Lewisi
The purpose of this study was to examine the ultrastructure of both young (dividing form) and adult (stationary form) of Trypanosoma lewisi. Changes observed between the two forms of the organism were related directly to data obtained from previous comparative biochemical studies conducted on these forms of Trypanosoma lewisi. digital.library.unt.edu/ark:/67531/metadc131627/
A Comparison of Specificity of Passive Transfer of Chemical Contact Hypersensitivity Following Different Methods of Sensitization
This thesis compares the specificity of passive transfer of chemical contact hypersensitivity following various methods of sensitization. digital.library.unt.edu/ark:/67531/metadc130801/
A Comparison of the Carbon Dioxide and Oxygen Rate of Change Methods for Measuring Primary Productivity
The purpose of this study was to demonstrate the variability of oxygen and carbon dioxide rate of change methods for measuring primary productivity and respiration in an aquatic environment. digital.library.unt.edu/ark:/67531/metadc131118/
Composition and Distribution of the Vegetation in Farm Pastures in Denton County, Texas
This investigation has for its aim the determination and the evaluation of the vegetational composition in certain farm pastures in Denton County, Texas. digital.library.unt.edu/ark:/67531/metadc53483/
Construction of a Pseudomonas aeruginosa Dihydroorotase Mutant and the Discovery of a Novel Link between Pyrimidine Biosynthetic Intermediates and the Ability to Produce Virulence Factors
The ability to synthesize pyrimidine nucleotides is essential for most organisms. Pyrimidines are required for RNA and DNA synthesis, as well as cell wall synthesis and the metabolism of certain carbohydrates. Recent findings, however, indicate that the pyrimidine biosynthetic pathway and its intermediates maybe more important for bacterial metabolism than originally thought. Maksimova et al., 1994, reported that a P. putida M, pyrimidine auxotroph in the third step of the pathway, dihydroorotase (DHOase), failed to produce the siderophore pyoverdin. We created a PAO1 DHOase pyrimidine auxotroph to determine if this was also true for P. aeruginosa. Creation of this mutant was a two-step process, as P. aeruginosa has two pyrC genes (pyrC and pyrC2), both of which encode active DHOase enzymes. The pyrC gene was inactivated by gene replacement with a truncated form of the gene. Next, the pyrC2 gene was insertionally inactivated with the aacC1 gentamicin resistance gene, isolated from pCGMW. The resulting pyrimidine auxotroph produced significantly less pyoverdin than did the wild type. In addition, the mutant produced 40% less of the phenazine antibiotic, pyocyanin, than did the wild type. As both of these compounds have been reported to be vital to the virulence response of P. aeruginosa, we decided to test the ability of the DHOase mutant strain to produce other virulence factors as well. Here we report that a block in the conversion of carbamoyl aspartate (CAA) to dihydroorotate significantly impairs the ability of P. aeruginosa to affect virulence. We believe that the accumulation of CAA in the cell is the root cause of this observed defect. This research demonstrates a potential role for pyrimidine intermediates in the virulence response of P. aeruginosa and may lead to novel targets for chemotherapy against P. aeruginosa infections. digital.library.unt.edu/ark:/67531/metadc4344/
Correlation of C'4 and Antibody Response to Antigen-Adjuvant Injections
This paper will attempt to determine whether the increased C'4 previously shown following antigen and adjuvant injection could be correlated to antibody increase following antigen injection. digital.library.unt.edu/ark:/67531/metadc130497/
A correlation of the Edaphic Factors with the Vegetation of the Woodbine sands, Denton County, Texas
The purpose of this study was to correlate the Vegetation of the Woodbine Sands with the edaphic factors. In the laboratory an analysis of the edephic factors was made of the twenty-two soil types collected from the three formations. The results of these and other analysis are shown in tables and graphs. The results indicate that the vegetational cover of an area that is uniform in its origin and in its resident soil factors is determined by the edaphic factors present. digital.library.unt.edu/ark:/67531/metadc29830/
A Correlation of the Habitat Factors with the Quantity of Bacterial Colonies as Observed by the Direct Microscopic Method on Twenty Soils of Denton County, Texas
The aim of this study is to determine what factors are most important in controlling the number of bacterial colonies found in twent represntative Denton County (Texas) soils during the growing season. digital.library.unt.edu/ark:/67531/metadc29869/
A Correlation of the Vegetation with the Soil Types of Haskell County, Texas
The problem has consisted, first, of a mapping of the soil types present in Haskell County; second, a collection of the existing vegetation of each soil type; third, an identification of the vegetation collected and observed; fourth, and lastly, a comparative study of the vegetation of each soil type in an effort to establish a correlation between the vegetation and the soil type. digital.library.unt.edu/ark:/67531/metadc96906/
The Cultural, Physiological, Morphological and Chemical Characteristics of an Actinomycete from Lake Waco, Texas
The purpose then of this paper has been to expand our knowledge of these aquatic forms by investigating the cultural, physiological, morphological, and chemical characteristics of an actinomycete isolated from the water supply, Lake Waco, of Waco, Texas. digital.library.unt.edu/ark:/67531/metadc130361/
Cytoplasmic Antigen Relationships among Streptomyces Species
The present study was concerned with the testing of antigenic material derived from a number of streptomycetes in an effort to establish an auxiliary taxonomic scheme based upon cytoplasmic antigen relationships among these organisms. digital.library.unt.edu/ark:/67531/metadc130701/
Degradation of Complex Carbon Compounds by Marine Actinomycetes
The purpose of this paper is to present a comparative study of marine bacteria, molds and actinomycetes in regard to their ability to degrade certain pure and mixed complex compounds possibly occurring in the lagoon waste traps of the Texas Gulf Coast. This comparison was made using a differential oxygen uptake as the index of specific compound utilization. digital.library.unt.edu/ark:/67531/metadc108067/
Degradation of Hexadecanol by Certain Bacterial Species
The purpose of this thesis is to determine the effect of hexadecanol on the populations of Pseudomonas and Alcaligenes species in reservoirs and determine their ability to utilize this compound as a carbon source. digital.library.unt.edu/ark:/67531/metadc107984/
Degradation of Homologous Polymerized Deoxyribonucleic Acid by Azotobacter Vinelandii ATCC 12837
The purpose of this study was twofold. The first was to isolate, purify, and characterize the deoxyribonucleic acid (DNA) of Azotobacter vinelandii ATCO 12837. The second was to determine if there was irreversible binding of homologous 32P labeled DNA to recipient A. vinelandii cells. digital.library.unt.edu/ark:/67531/metadc131569/
Density, Distribution, Production and Drift of Benthic Fauna in a Reservoir Receiving Thermal Discharges from a Steam Electric Generating Plant
The effects of thermal discharges on the density, distribution, production, and drift of benthic organisms were studied at North Lake reservoir. digital.library.unt.edu/ark:/67531/metadc131579/
The Destruction of Enterobacteriaceae by the Sewage Plants of Decatur, Texas.
The nature of this problem divides itself into two parts, that is, a study of the old sewage plants in operation through the summer of 1947 and a study of the new plant put in operation during the fall of the same year. digital.library.unt.edu/ark:/67531/metadc83559/
Detection of Mercury Among Avian Trophic Levels at Caddo Lake and Lake Lewisville, TX
Mercury (Hg) is a globally distributed toxicant that has been shown to have negative effects on birds. in the United States, avian taxa have been shown to possess high Hg concentrations in the northeast, Great Lakes and Everglades ecosystems; however, few studies have measured avian Hg concentrations in other geographic regions. Previous studies have documented high Hg concentrations in multiple organisms in east Texas, but birds were not included in these studies. the main objective of the present study was to quantify Hg concentrations in birds in differing trophic levels at Caddo Lake and Lake Lewisville, TX. Results suggest that Hg concentrations may be high enough to negatively impact some bird taxa, particularly those at high trophic levels, residing at both Caddo Lake and Lake Lewisville. digital.library.unt.edu/ark:/67531/metadc115153/
A Determination of the Effects of Various Concentrations of Sodium Chloride upon the Growth of Three Species of Bacteria
The problem in this investigation is to determine the effects of various concentrations of sodium chloride upon the growth of three species of bacteria. An effort has been made to solve this problem, not only by a study of the relevant literature, but also by laboratory research consisting of cultivation and observation of the three organisms which were arbitrarily chosen for this study. digital.library.unt.edu/ark:/67531/metadc70335/
Developing Range Condition Classes for the North Grand Prairie of Texas
This paper deals with a study of the ranch lands in Cooke, Wise, Denton, and Montague Counties, which are located in the North Grand Prairie of Texas. digital.library.unt.edu/ark:/67531/metadc53448/
The Dispersal of Algae and Protozoa by Selected Odonata
This study was designed to show what dissemules may be carried by selected genera of Odonata, where the dissemules may be predominantly carried on the selected insects and to relate the behavior of the selected Odonata to frequency of occurrence of micro-organisms on the insects. digital.library.unt.edu/ark:/67531/metadc163882/
Distribution of Phosphates in a Sewage Plant and its Receiving Waters
The purpose of this paper is to detail the distribution and quantity of soluble phosphates in an activated sludge plant, its discharge creek, and receiving reservoir. The resultant analyses and comparison of data should provide some better understanding of the fate of phosphorus in a Southwestern waterway system. digital.library.unt.edu/ark:/67531/metadc131093/