UNT Theses and Dissertations - 15 Matching Results

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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.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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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
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Cloning of Carbonic Anhydrase from Cotton (Gossypium hirsutum L.)

Description: Carbonic anhydrase is a ubiquitous zinc-metalloenzyme that catalyzes the interconversion of carbon dioxide and carbonate and has been found to play a wide range of roles in animals, plants and bacteria. Cotton genomic and cDNA libraries were screened for the plastidial isoform of carbonic anhydrase. The nucleotide sequences of two 1.2 Kb partial cDNA clones were determined. These clones exhibit high homology to carbonic anhydrases from other dicot plants and possess all the expected peptide mot… more
Date: December 1998
Creator: Local, Andrea
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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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
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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DNA Typing of HLA-B by PCR with Primer Mixes Utilizing Sequence-Specific Primers

Description: The aim of this study was to design a resolution typing system for the HLA-B gene. This technique involves a one-step PCR reaction utilizing genomic DNA and sequence-specific primers to determine the specificity of each allele and to produce a larger primer data base ideal for serological analysis. The application of this technique to serological analysis can improve serology detection which is currently hindered by antibody cross-reactivity and the unavailability of useful typing reagents.
Date: August 1997
Creator: Chiu, Angela Chen-Yen
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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How Do Enzymes Wear Out? Effects of Posttranslational Modifications on Structure and Stability of Proteins; The Triosephosphate Isomerase Model

Description: Triosephosphate isomerase (EC 5.3.1.1., TPI) undergoes specific posttranslational modifications (deamidation and oxidation) which are believed to initiate protein turnover by destabilization of the dimer. The crystal structures, amino acid sequences, and aging related changes of TPI from various species have been independently characterized by several laboratories. TPI has thus become the prototype enzyme for examining the initial steps in protein turnover. The binding of substrate enhances the… more
Date: December 1991
Creator: Sun, An Qiang
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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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)
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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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-
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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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.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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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)
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Phytoestrogens in Two Dioecious Species: Isolation, Characterization and Role in Plant Reproduction

Description: A highly specific steroid regulated transcription system system in Saccharomyces cerevisae was used to screen for phytoestrogens indioecious plants. Yeast cells were co-transformed with a human estrogen receptor expression plasmid and a reporter plasmid containing the E. coli β-galactosidase gene.
Date: May 1996
Creator: Maier, Camelia G. A. (Camelia Gabriela-Anca)
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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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
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Regulation of Colony-Stimulating Factor-1 Biosynthesis

Description: Recent studies suggest that synthesis of the Colony-stimulating factor (CSF) is a well regulated process. However, the molecular mechanisms of the signal transduction of the various inducers of CSF such as monokines and lymphokines are not well understood. Using Interleukin 1 (IL-1) stimulation of CSF-1 in the MIA PaCa-2 cell line as a model system, the involvement of G-protein has been studied. The IL-1 induction of CSF-1 synthesis can be inhibited by both Pertussis toxin and Cholera toxin, wh… more
Date: May 1990
Creator: Ku, Chun-Ying
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Subcloning and Nucleotide Sequence of the xylO/PUWCMA Region from the Pseudomonas putida TOL Plasmid pDK1

Description: The TOL plasmids of Pseudomonas putida encode enzymes required for the oxidation of toluene and other related aromatic compounds. These genes are organized into two operons, the xylUWCMABN operon (upper), and the xylXYZLTEGFJQKIH operon (lower). Here we report the nucleotide sequence of a 7107 bp segment of the TOL pDK1 plasmid encoding the region just upstream of the "upper" operon through the genes encoding xylUWCMA. Sequence analysis, comparison of base-usage patterns, codon-usage patterns, … more
Date: December 1997
Creator: Guigneaux, Michelle M. (Michelle Marie)
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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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
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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