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open access

In Situ Hybridization of 70 kD Heat Shock Protein mRNA in a Rat Model of Ethanol Self-Administration

Description: Sucrose fading was used to initiate self-administration of ethanol on an FR4 schedule in male Fischer 344 rats. Rats showed low response rates for ethanol alone. After administration of liquid diet containing ethanol, ethanol intake increased over levels prior to administration of the liquid diet. In situ hybridization compared mRNA for the inducible or constitutive 70 kD heat shock proteins in ethanol and nonethanol rats. Both inducible and constitutive mRNAs were found in nonethanol and ethan… more
Date: December 1994
Creator: Ott-Reeves, Ellen (Ellen Theresa)
Partner: UNT Libraries
open access

Mutation Rate Analysis of the Human Mitochondrial D-loop and its Implications for Forensic Identity Testing

Description: To further facilitate mitochondrial DNA (mtDNA) sequence analysis for human identity testing, a better understanding of its mutation rate is needed. Prior to the middle 1990's the mutation rate applied to a forensic or evolutionary analysis was determined by phylogenetic means, This method involved calculating genetic distances as determined by amino acid or DNA sequence variability within or between species. The mutation rate as determined by this method ranged from 0.025-0.26 nucleotide subst… more
Date: May 2000
Creator: Warren, Joseph E.
Partner: UNT Libraries
open access

Cassette Systems for Creating Intergeneric Hybrid ATCases

Description: Cassette systems for creating intergeneric hybrid ATCases were constructed. An MluI restriction enzyme site was introduced at the carbamoylphosphate binding site within the pyrB genes of both Pseudomonas putida and Escherichia coli. Two hybrids, E. coli pyrB polar domain fused with P. putida pyrB equatorial domain and P. putida pyrB polar domain fused with E. coli pyrB equatorial domain, are possible. The intergeneric E. coli-P. putida hybrid pyrB gene was constructed and found to encode an a… more
Date: December 1999
Creator: Simpson, Luci N.
Partner: UNT Libraries
open access

Biochemical Systematics of the Genus Sophora

Description: Three unusual amino acids, y-amino-n-butyric acid, pipecolic acid, and 4-hydroxypipecolic acid, and an uncommon dipeptide, y-glutamyltyrosine, have been isolated and characterized from the seeds of members of the genus Sophora. Structural proof of these compounds was carried out by paper chromatography, thin-layer chromatography, column chromatography on amino acid analyzer, infrared, nuclear magnetic resonance, mass spectrometry, and C, H, N analysis. The presence and absence of these compound… more
Date: December 1973
Creator: Izaddoost, Mohamed
Partner: UNT Libraries
open access

Mutagenized HLA DNA Constructs: Tools for Validating Molecular HLA Typing Methodologies

Description: This study describes the development and validation of mutagenized cloned DNA constructs, which correspond to the polymorphic regions of the class II region of the HLA complex. The constructs were used to verify the allelic specificity of primers and probes in polymerase chain reaction (PCR)-based HLA typing assays such as Sequence Specific Primers (SSP) and Sequence Specific Oligonucleotide Probes (SSOP). The constructs consisted of the entire polymorphic region of exon 2 of class II HLA allel… more
Date: May 1999
Creator: Schulte, Kathleen Q.
Partner: UNT Libraries
open access

Genetic and Cellular Analysis of Anoxia-Induced Cell Cycle Arrest in Caenorhabditis elegans

Description: The soil-nematode Caenorhabditis elegans survives oxygen deprivation (anoxia < 0.001 kPa of O2, 0% O2) by entering into a state of suspended animation during which cell cycle progression at interphase, prophase and metaphase stage of mitosis is arrested. I conducted cell biological characterization of embryos exposed to various anoxia exposure times, to demonstrate the requirement and functional role of spindle checkpoint gene san-1 during brief anoxia exposure. I conducted a synthetic lethal s… more
Date: December 2008
Creator: Hajeri, Vinita A.
Partner: UNT Libraries
open access

Construction of a Cloning Vector Based upon a Rhizobium Plasmid Origin of Replication and its Application to Genetic Engineering of Rhizobium Strains

Description: Rhizobia are Gram-negative, rod-shaped, soil bacteria with the ability to fix atmospheric nitrogen into ammonia as symbiont bacteroids within nodules of leguminous plant roots. Here, resident Rhizobium plasmids were studied as possible sources of components for the construction of a cloning vector for Rhizobium species.
Date: May 1992
Creator: Jeong, Pyengsoo
Partner: UNT Libraries
open access

Effects of a Methylcholanthrene-Induced Lymphosarcoma on Various Tissues of DBA/1J and Swiss White Mice

Description: This investigation was concerned with characterizing effects of this tumor line on lipid metabolism in DBA/lJ mice and serum protein levels and cellular changes in DBA/lJ and Swiss white mice. Total lipids, lipid phosphorus, neutral lipids, and changes in fatty acids were determined in liver, spleen, skin, and tumor of DBA/lJ mice bearing the lymphosarcoma at various days after injection of tumor cells.
Date: May 1973
Creator: Lindsey, Terri Jay
Partner: UNT Libraries
open access

Subcloning and Nucleotide Sequence of Two Positive Acting Regulatory Genes, xy1R and xy1S, from the Pseudomonas putida HS1 TOL Plasmid PDK1

Description: TOL plasmids of Pseudomonas putida encode enzymes for the degradation of toluene and related aromatics. These genes are organized into two operons regulated by the Xy1R and Xy1S transcriptional activators. Previous analysis of the TOL pDK1 catechol-2,3-dioxygenase gene (xy1E) and a comparison of this gene to xy1E from the related TOL plasmid pWW0, revealed the existance of a substantial level of sequence homology (82%).
Date: May 1992
Creator: Chang, Teh-Tsai
Partner: UNT Libraries
open access

Nucleotide Sequence Determination, Subcloning, Expression and Characterization of the xy1LT Region of the Pseudomonas putida TOL Plasmid pDK1

Description: The complete nucleotide sequence of the region encoding the DHCDH function of the pDK1 lower operon was determined. DNA analysis has shown the presence of two open reading frames, one gene consisting of 777 nucleotides encoding a polypeptide of 27.85 kDa and another gene of 303 nucleotides encoding a polypeptide of 11.13 kDa. The results of enzymatic expression studies suggest that DHCDH activity is associated only with xy1L. However although the addition of xy1T cell-free extracts to xy1L cell… more
Date: December 1992
Creator: Baker, Ronald F. (Ronald Fredrick)
Partner: UNT Libraries
open access

Cell-Free Recovery and Isotopic Identification of Cyanide Degrading Enzymes from Pseudomonas Fluorescens

Description: Cell-free extracts from Pseudomonas fluorescens NCIMB 11764 catalyzed the degradation of cyanide into products that included C02, formic acid, formamide and ammonia. Cyanide-degrading activity was localized to cytosolic cell fractions and was observed at substrate concentrations as high as 100 mM. Two cyanide degrading activities were identified by: (i) the determination of reaction products stoichiometries, (ii) requirements for NADH and oxygen, and (iii) kinetic analysis. The first activity p… more
Date: December 1995
Creator: Wang, Chien-Sao
Partner: UNT Libraries
open access

Isolation and Characterization of the Operon Containing Aspartate Transcarbamoylase and Dihydroorotase from Pseudomonas aeruginosa

Description: The Pseudomonas aeruginosa ATCase was cloned and sequenced to determine the correct size, subunit composition and architecture of this pivotal enzyme in pyrimidine biosynthesis. During the course of this work, it was determined that the ATCase of Pseudomonas was not 360,000 Da but rather present in a complex of 484,000 Da consisting of two different polypeptides (36,000 Da and 44,000 Da) with an architecture similar to that of E. coli ATCase, 2(C3):3(r2). However, there was no regulatory polype… more
Date: May 1993
Creator: Vickrey, John F. (John Fredrick), 1959-
Partner: UNT Libraries
open access

Regulation, Evolution, and Properties of the ato Qperon and its Gene Products in Escherichia coli

Description: The regulation of short chain fatty acid metabolism has been examined. Metabolism of acetoacetate, and short chain fatty acids such as butyrate and valerate, is predicated upon the expression of genes of the ato operon. Acetoacetate induces expression of a CoA transferase (encoded by the atoDA genes) and expression of a thiolase (encoded by the atoB gene). Metabolism of saturated short chain fatty acids requires the activities of the transferase and thiolase and enzymes of 6-oxidation as well. … more
Date: August 1993
Creator: Chen, Chaw-Yuan
Partner: UNT Libraries
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Virulence Factor Production in PyrE Mutants of Pseudomonas Aeruginosa

Description: It has been shown previously in our lab that mutations in the pyrimidine pathway reduced the ability of Pseudomonas aeruginosa to produce virulence factors. Knockout mutations in pyrB, pyrC and pyrD genes of the pyrimidine pathway showed that virulence factor production was decreased. Pyoverdin, pyocyanin, hemolysin, iron chelation, motility, and adherence are all considered virulence factors. Here I further investigate the effects of mutations in the pyrimidine pathway by studying a pyrE mutan… more
Date: May 2010
Creator: Niazy, Abdurahman
Partner: UNT Libraries
open access

Bacterial Cyanide Assimilation: Pterin Cofactor and Enzymatic Requirements for Substrate Oxidation

Description: Utilization of cyanide as the sole nitrogen source by Pseudomonas fluorescens NCIMB 11764 (Pf11764) occurs via oxidative conversion to carbon dioxide and ammonia, the latter satisfying the nitrogen requirement. Substrate attack is initiated oxygenolytically by an enzyme referred to as cyanide oxygenase (CNO), which exhibits properties of a pterin-dependent hydroxylase. The pterin requirement for Pf11764 CNO was satisfied by supplying either the fully (tetrahydro) or partially (dihydro) reduced … more
Date: May 2004
Creator: Dolghih, Elena
Partner: UNT Libraries
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Isolation of a Pseudomonas aeruginosa Aspartate Transcarbamoylase Mutant and the Investigation of Its Growth Characteristics, Pyrimidine Biosynthetic Enzyme Activities, and Virulence Factor Production

Description: The pyrimidine biosynthetic pathway is an essential pathway for most organisms. Previous research on the pyrimidine pathway in Pseudomonas aeruginosa (PAO1) has shown that a block in the third step of the pathway resulted in both a requirement for exogenous pyrimidines and decreased ability to produce virulence factors. In this work an organism with a mutation in the second step of the pathway, aspartate transcarbamoylase (ATCase), was created. Assays for pyrimidine intermediates, and virule… more
Date: December 2004
Creator: Hammerstein, Heidi Carol
Partner: UNT Libraries
open access

Purification and Characterization of Proteolytic Aspartate Transcarbamoylase (ATCase) from Burkholderia cepacia 25416 and Construction of a pyrB1 Knock-out Mutant

Description: Burkholderia cepacia is a common soil bacterium of significance in agriculture and bioremediation. B. cepacia is also an opportunistic pathogen of humans causing highly communicable pulmonary infections in cystic fibrosis and immunocompromized patients. The pyrB gene encoding ATCase was cloned and ATCase was purified by the glutathione S-transferase gene fusion system. The ATCase in B. cepacia has been previously classified as a class A enzyme by Bethell and Jones. ATCase activity gels show… more
Date: December 2004
Creator: Kim, Seongcheol
Partner: UNT Libraries
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The regulatory roles of PyrR and Crc in pyrimidine metabolism in Pseudomonas aeruginosa

Description: The regulatory gene for pyrimidine biosynthesis has been identified and designated pyrR. The pyrR gene product was purified to homogeneity and found to have a monomeric molecular mass of 19 kDa. The pyrR gene is located directly upstream of the pyrBC' genes in the pyrRBC' operon. Insertional mutagenesis of pyrR led to a 50- 70% decrease in the expression of pyrBC', pyrD, pyrE and pyrF while pyrC was unchanged. This suggests that PyrR is a positive activator. The upstream regions of the pyrD, py… more
Date: August 2001
Creator: Patel, Monal V.
Partner: UNT Libraries
open access

A New LC Column for the Separation and the Quantitation of Nucleotides

Description: A new column, Dionex AS4A, (polystyrenedivinylbenzene matrix) used for the separation of ribonucleotides and deoxyribonucleotides for the first time, and previously used for ion analysis was found superior to conventional silica columns because it separates ribonucleotides and deoxyribonucleotides. Resolution of dGTP was not possible with the Dionex column and CTP and GDP often co-eluted. Using conventional silica columns, monophosphates separated from diphosphates and diphosphates from triphos… more
Date: December 1987
Creator: Brock, Patricia C. (Patricia Charlene)
Partner: UNT Libraries
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A Study of the Interaction of Co-Insult Treatments with Methylmercuric Chloride and X-Irradiation and Demonstration of a Peroxide Induced Protective Mechanism

Description: The initial purpose of this work was to investigate the interaction of methylmercuric chloride (MMC) and X-irradiation given as a co-insult upon the rat blood-brain barrier (BBB). The indicators used to determine BBB alterations were mortality and the in vivo tissue uptake of radioactive sulfate administered as 3 5S-sodium sulfate. The results of the interaction studies indicated a neutralization of effects when MMC and X-irradiation were given together. X-irradiation as a single insult general… more
Date: August 1975
Creator: Earhart, James M.
Partner: UNT Libraries
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Physical Map between Marker 8O7 and 146O17 on the Medicago truncatula Linkage Group 1 that Contains the NIP Gene

Description: The Medicago truncatula NIP gene is located on M. truncatula Linkage Group 1. Informative recombinants showed crossovers that localize the NIP gene between markers 146O17 and 23C16D. Marker 164N9 co-segregates with the NIP gene, and the location of marker 164N9 is between markers 146O17 and 23C16D. Based upon data from the Medicago genome sequencing project, a subset of the model legume Medicago truncatula bacterial artificial chromosomes (BACs) were used to create a physical map on the DNA in … more
Date: December 2007
Creator: Lee, Yi-Ching
Partner: UNT Libraries
open access

Applications of Molecular Genetics to Human Identity.

Description: The primary objectives of this project were: 1. to develop improved methods for extraction of DNA from human skeletal remains, 2. to improve STR profiling success of low-copy DNA samples by employing whole genome amplification to amplify the total pool of DNA prior to STR analysis, and 3. to improve STR profiling success of damaged DNA templates by using DNA repair enzymes to reduce the number/severity of lesions that interfere with STR profiling. The data from this study support the following … more
Date: December 2008
Creator: Turnbough, Meredith A.
Partner: UNT Libraries
open access

Development of a Real-time Pcr Assay for the Detection of Campylobacter Jejuni and Campylobacter Coli.

Description: Campylobacter organisms are the most commonly reported bacterial causes of foodborne infection in the world, with Campylobacter jejuni and Campylobacter coli responsible for over 99% of reported infections. Traditionally, Campylobacter species detection is an arduous process, requiring a special incubation environment as well as specific growth media for an extended growth period. The development of a rapid and reliable diagnostic tool for the detection of Campylobacter species would be a valu… more
Date: May 2009
Creator: Lewis, Sally
Partner: UNT Libraries
open access

Origin and Role of Factor Viia

Description: Factor VII, the initiator of the extrinsic coagulation cascade, circulates in human plasma mainly in its zymogen form, Factor VII and in small amounts in its activated form, Factor VIIa. However, the mechanism of initial generation of Factor VIIa is not known despite intensive research using currently available model systems. Earlier findings suggested serine proteases Factor VII activating protease, and hepsin play a role in activating Factor VII, however, it has remained controversial. In thi… more
Date: December 2013
Creator: Khandekar, Gauri
Partner: UNT Libraries
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