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Characterization of the Aspartate Transcarbamoylase that is Found in the pyrBC’ Complex of Bordetella Pertussis

Description: 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-… more
Date: December 2001
Creator: Dill, Michael T
Partner: UNT Libraries

BioInformatics, Phylogenetics, and Aspartate Transcarbamoylase

Description: In this research, the necessity of understanding and using bioinformatics is demonstrated using the enzyme aspartate transcarbamoylase (ATCase) as the model enzyme. The first portion of this research focuses on the use of bioinformatics. A partial sequence of the pyrB gene found in Enterococcus faecalis was submitted to GenBank and was analyzed against the contiguous sequence from its own genome project. A BLAST (Basic Local Alignment Search Tool; Atschul, et al., 1990) was performed in or… more
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Date: August 2000
Creator: Cooke, Patrick Alan
Partner: UNT Libraries
open access

Carbachol- and ACPD-Induced Phosphoinositide Responses in the Developing Rat Neocortex

Description: Signal transduction via the phosphoinositide (PI) second messenger system has key roles in the development and plasticity of the neocortex. The present study localized PI responses to individual cortical layers in slices of developing rat somatosensory cortex. The acetylcholine agonist carbachol and the glutamate agonist trans-1-amino-1,3-cyclopentanedicarboxylic acid (ACPD) were used to stimulate PI turnover. The PI responses were compared to the distribution of the corresponding PI-linked rec… more
Date: August 2000
Creator: Hartgraves, Morri D.
Partner: UNT Libraries
open access

Requirements for Cell-Free Cyanide Oxidation by Pseudomonas Fluorescens NCIMB 11764

Description: The involvement of cyanide oxygenase in the metabolism of pyruvate and a-ketoglutarate-cyanohydrin was investigated and shown to occur indirectly by the consumption of free cyanide arising from the cyanohydrins via chemical dissociation. Thus, free cyanide remains the substrate, for which the enzyme displays a remarkably high affinity (Kmapp,4 mM). A model for cyanide utilization is therefore envisioned in which the substrate is initially detoxified by complexation to an appropriate lig… more
Date: August 2000
Creator: Parab, Preeti
Partner: UNT Libraries
open access

Scientific Considerations of Olestra as a Fat Substitute

Description: Olestra is, a sucrose polyester, a noncaloric fat substitute, made from sucrose and several fatty acid esters. It has been approved by the FDA as a food additive used in preparing low-fat deep-frying foods such as savory snacks. Available literature on olestra was evaluated that had both positive and negative connotations. Clinical trials in numerous species of animals including humans were conducted to determine if olestra would affect the utilization and absorption of macro- and micronutrient… more
Date: December 1999
Creator: Rattagool, Kullakan
Partner: UNT Libraries
open access

Comparative Biochemistry and Evolution of Aspartate Transcarbamoylase from Diverse Bacteria

Description: Aspartate transcarbamoylase (ATCase) catalyzes the first committed step in pyrimidine biosynthesis. Bacterial ATCases are divided into three classes, A, B and C. Class A ATCases are largest at 450-500, are. dodecamers and represented by Pseudomonas ATCase. The overlapping pyrBC' genes encode the Pseudomonases ATCase, which is active only as a 480 kDa dodecamer and requires an inactive pyrC'-encoded DHOase for ATCase activity. ATCase has been studied in two non-pathogenic members of Mycobacteriu… more
Date: May 1999
Creator: Hooshdaran, Massoumeh Ziba
Partner: UNT Libraries
open access

Biodegradation of Certain Petroleum Product Contaminants in Soil and Water By Selected Bacteria

Description: Soil contamination by gasoline underground storage tanks is a critical environmental problem. The results herein show that in situ bioremediation using indigenous soil microorganisms is the method of choice. Five sites were selected for bioremediation based on the levels of benzene, toluene, ethylbenzene and xylene and the amount of total petroleum hydrocarbons in the soil. Bacteria capable of degrading these contaminants were selected from the contaminated sites and grown in 1,200 I mass cultu… more
Date: December 1995
Creator: Nevárez-Moorillón, Guadalupe Virginia
Partner: UNT Libraries
open access

Intracellular Location of Carotenoid Pigments in Yeast-Phase Cells of Wangiella Dermatitidis and Cell Wall Morphology After Enzyme Treatment

Description: Carotenoid pigments in W. dermatitidis, the first pathogenic, dematiaceous fungus in which carotenoid pigments nave been reported, are located primarily (81%) in lipid organelles which floated on the surface of the supernatant fraction of lysed cells. Pigment in this fraction could be extracted with ethyl ether without prior treatment with acetone indicating the pigment is unbound in the lipid organelle. Eight percent remains after exhaustive ether extraction and is recovered after the sample i… more
Date: December 1991
Creator: Foster, Linda Ann
Partner: UNT Libraries
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Studies of the Membrane and DNA Gyrase Inhibiting Antibiotics on Pigment Synthesis in Corynebacterium Poinsettiae

Description: The purpose of this study was (1) to determine whether a correlation exists among the protein profiles, extracted from cell membranes of mutants belonging to five pigment cluster groups, (2) to locate the protein moiety and cartenoprotein complex in the membranes of wild type and colorless mutant (designated W-19) of C. poinsettae and to show whether there are any structural differences between cell membranes of the wild type and a colorless mutant, (3) to determine the effect of six antibioti… more
Date: August 1988
Creator: Tabarya, Daniel
Partner: UNT Libraries
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Characterization of the Pigment-Protein and Pigment-ester of Xanthomonas Campestris Pv. Juglandis

Description: The objectives of this project were to develop a high performance liquid chromatographic method for separating the pigment esters mixture, to determine the locations of the pigment moiety in the isolated esters using pholosiphases, and to characterize the pigment-protein complex and determine its distribution in other bacteria. Saponification of the two pigment esters 1 and 2 with aqueous KOH yielded two free pigments on TLC plates developed by two solvent systems. The fasters moving of these t… more
Date: May 1987
Creator: Lawani, Leonard Olu
Partner: UNT Libraries
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Induction of Interferon Messenger RNA and Expression of Cellular Oncogenes in Human Lymphoblastoid Cells

Description: The purposes of this study was to demonstrate the induction of alpha interferon mRNA in Sendai virus-induced Namalava cells, to follow the level of alpha interferon mRNA synthesis at the transcriptional level, and to determine whether the Namalava cell line expresses the c-myc oncogene and to what degree. The amount of c-myc message deteted in Namalva cell RNA was about one-tenth that of Daudi cell RNA, whereas no difference in the amount of the c-Ha-ras message was observed between the two cel… more
Date: December 1986
Creator: Mahmoudi, Massoud
Partner: UNT Libraries
open access

Characterization of the Pigment-Protein Complex in Corynebacterium Poinsettiae

Description: The purpose of this study was to completely characterize the protein moiety in the caroteno complex in C. poinsettae, determine if the distribution and level of protein in the pigment-protein complex in membranes of the wild type and in a colorless mutant could account for the differences in the stability of the membrane, and to determine if this protein is common to other pigmented and non-pigmented organisms. Also, electron microscopy of cell membranes of C. poinsettiae which had been exposed… more
Date: May 1986
Creator: Ebadati, Nasrollah D.
Partner: UNT Libraries
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Aquatic Heterotrophic Bacteria Active in the Biotransformation of Anthracene and Pentachlorophenol

Description: Dominant genera of bacteria were isolated from three river waters during anthracene and pentachlorophenol biotransformation studies. The genera Pseudomonas, Acinetobacter, Micrococcus, Chromobacterium, Alcaligenes, Azomonos, Bacillus, and Flavobacterium were capable of biotransforming one or both of these compounds. These isolates were subjected to further biotransformation tests, including river water and a basal salt medium with and without additional glucose. The results of these experiments… more
Date: August 1985
Creator: Entezami, Azam A. (Azam Alsadat)
Partner: UNT Libraries
open access

Degradation of Humic Substances by Aquatic Bacteria

Description: A variety of aquatic bacteria were isolated and tested for their ability to degrade humic substances and their aromatic residues/monomers which serve as precursors of the trihalomethanes (THMs) found in chlorinated drinking waters. The majority of them were Gram-negative, oxidative types dominated by pseudomonads. Most of the 146 isolates were found to utilize as their sole source of carbon several or more of ten aromatic compounds known to be products of degradation of humus and also to be pre… more
Date: August 1985
Creator: Baiu, Saleh Hamed Salem
Partner: UNT Libraries
open access

Immune Response of the Rat to Outer Membrane Proteins of Legionella Pneumophila

Description: Outer membrane proteins (OMPs) were recovered from eleven strains (eight serogroups) of Legionella pneumophila by sequential treatment with Tris buffer (pH 8), citrate buffer(pH 2.75) and Tris buffer (pH 8). Transmission electron microscopy revealed clearly the separation of the outer membrane from the bacteria. The development of delayed hypersensitivity was also noted by measuring the area of arythema and induration produced by intradermal injections of the MPSs from Chicago 8 strain. The adj… more
Date: August 1985
Creator: Ahanotu, Ejemihu Ndu
Partner: UNT Libraries
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L-asparaginase II Production by Escherichia coli

Description: Growth of Escherichia coli A-l under aerobic conditions in an enriched medium with a total amount of 0.2 per cent glucose was biphasic and asparaginase II activity was detected after depletion of ammonia from the growth medium in the second phase of growth. Glucose was exhausted two hours before ammonia and three hours before asparaginase II activity was detected. The concentration of 3',5'-cyclic adenosine monophosphate was found to fluctuate when the dissolved oxygen in the medium reached a l… more
Date: May 1985
Creator: Johnson, Terrance L. (Terrance Lewyne), 1950-
Partner: UNT Libraries
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Discovery of a Thermophilic Nitrogen Fixing Bacterium

Description: The thermophilic bacterium designated NT-7 was shown to reduce acetylene to ethylene at 35 C. It was found that the organism does not reduce acetylene when it is grown in Burk's medium with 0.3 per cent (w/v) NH4 N0 3 . Reduction of acetylene at 55 C could not be demonstrated due to insolubility of acetylene in Burk's medium at this temperature. It was shown that the bacterium NT-7 can not grow in the absence of atmospheric nitrogen at 55 C when combined nitrogen is not supplied with the nutrie… more
Date: August 1977
Creator: Tabarya, Daniel
Partner: UNT Libraries
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A Study of the Water-Soluble Antigens from Virulent and Attenuated Biotypes of Brucella abortus

Description: Through chemical analysis and ion exchange chromatography of watersoluble antigens, this investigation supports the view that the majority of differences between the biotypes are quantitative. It was also found that strains demonstrate distinct, qualitative differences when compared to the attenuated strain 19 by immunodiffusion and thin-layer polyacrylamide gel, isoelectric focusing. These differences include the presence of antigens on virulent strains that are absent on strain 19. In additio… more
Date: May 1977
Creator: Brodeur, Richard D.
Partner: UNT Libraries
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The Detection of Poliovirus in Denton Sewage by Immunofluorescence and Immunodiffusion Techniques

Description: Several final sewage effluents from the Denton Disposal Plant were demonstrated to contain Poliovirus types II and III. Pleated encapsulated filters at pH3.5 enhanced the recovery of the Poliovirus at a higher tier in comparison with nitrocellulose filter (Millipore) and glass fiber filter of pore size 0.45u. This thesis explores problems that face us today in our quest to eliminate viral pathogens from the natural and waste water needed for human, domestic, and industrial consumption. Prelimin… more
Date: August 1975
Creator: Olaiya, Felix Ayodele
Partner: UNT Libraries
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