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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
Item Type: Refine your search to only Thesis or Dissertation
open access

Changes in Gene Expression Levels of the Ecf Sigma Factor Bov1605 Under Ph Shift and Oxidative Stress in the Sheep Pathogen Brucella Ovis

Description: 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… more
Date: December 2012
Creator: Kiehler, Brittany Elaine
Item Type: Refine your search to only Thesis or Dissertation
open access

Multiple Activities of Aspartate Transcarbamoylase in Burkholderia cepacia: Requirement for an Active Dihydroorotase for Assembly into the Dodecameric Holoenzyme

Description: The aspartate transcarbamoylase (ATCase) was purified from Burkholderia cepacia 25416. In the course of purification, three different ATCase activities appeared namely dodecameric 550 kDa holoenzyme, and two trimeric ATCases of 140 kDa (consists of 47 kDa PyrB subunits) and 120 kDa (consists of 40 kDa PyrB subunits) each. The 120 kDa PyrB polypeptide arose by specific cleavage of the PyrB polypeptide between Ser74 and Val75 creating an active polypeptide short by 74 amino acids. Both the 40 and… more
Date: December 2010
Creator: Kim, Hyunju
Item Type: Refine your search to only Thesis or Dissertation
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
Item Type: Refine your search to only Thesis or Dissertation
open access

Genetic Characterization of Central and South American Populations of Scarlet Macaw (Ara macao)

Description: The wild populations of the Scarlet Macaw subspecies native to southern Mexico and Central America, A. m. cyanoptera, have been drastically reduced over the last half century and are now a major concern to local governments and conservation groups. Programs to rebuild these local populations using captive bred specimens must be careful to reintroduce the native A. m. cyanoptera, as opposed to the South American nominate subspecies (A. m. macao) or hybrids of the two subspecies. Molecular marker… more
Date: May 2016
Creator: Kim, Tracy Ann
Item Type: Refine your search to only Thesis or Dissertation
open access

Isolation and analysis of cotton genomic clones encompassing a fatty acid desaturase (FAD2) gene

Description: Polyunsaturated fatty acids are major structural components of plant chloroplast and endoplasmic reticulum membranes. Two fatty acid desaturases (designated FAD2 and FAD3) desaturate 75% of the fatty acids in the endoplasmic reticulum. The w -6 fatty acid desaturase (FAD2) may be responsible for cold acclimation response, since polyunsaturated phospholipids are important in helping maintain plant viability at lowered temperatures. To study regulation of FAD2 gene expression in cotton, a FAD2 g… more
Date: May 2001
Creator: Kongcharoensuntorn, Wisatre
Item Type: Refine your search to only Thesis or Dissertation
open access

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

Structure-Function Studies on Aspartate Transcarbamoylase and Regulation of Pyrimidine Biosynthesis by a Positive Activator Protein, PyrR in Pseudomonas putida

Description: The regulation of pyrimidine biosynthesis was studied in Pseudomonas putida. The biosynthetic and salvage pathways provide pyrimidine nucleotides for RNA, DNA, cell membrane and cell wall biosynthesis. Pyrimidine metabolism is intensely studied because many of its enzymes are targets for chemotheraphy. Four aspects of pyrimidine regulation are described in this dissertation. Chapter I compares the salvage pathways of Escherichia coli and P. putida. Surprisingly, P. putida lacks several salvag… more
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Date: December 2003
Creator: Kumar, Alan P.
Item Type: Refine your search to only Thesis or Dissertation
open access

Genetic and Environmental Factors that Mediate Survival of Prolonged Oxygen Deprivation in the Nematode Caenorhabditis Elegans

Description: Ischemic events of even a very short duration are not tolerated Ill in humans. The human cost of ischemia, when looked at as combined cardiovascular disease, dwarfs all other causes of death in the United States. Annually, CVD kills as many people in the US as does cancer, chronic lower respiratory disease, accidents, and diabetes mellitus combined. In 2005 (the latest year for which final statistics are available), CVD was responsible for 864,480 deaths or 35.3 percent of total deaths for t… more
Date: August 2010
Creator: LaRue, Bobby Lee, Jr.
Item Type: Refine your search to only Thesis or Dissertation
open access

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
Item Type: Refine your search to only Thesis or Dissertation
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
Item Type: Refine your search to only Thesis or Dissertation
open access

Effects of a Methylcholanthrene-Induced Lymphosarcoma on the Blood of DBA/1J Mice

Description: This investigation was concerned with characterizing a tumor line induced and maintained in this laboratory. Various chemical assays, cell counts, and electron microscopy were the methods employed to characterize the blood of mice bearing the tumor at days 3, 6, 9, and 12 after injection of the 1.2 x 10^8 tumor cells.
Date: May 1972
Creator: Lindsey, Jerri Kay
Item Type: Refine your search to only Thesis or Dissertation
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
Item Type: Refine your search to only Thesis or Dissertation
open access

Genetic Analysis of Development and Behavior in Hypoxia and Cellular Characterization of Anoxia Induced Meiotic Prophase Arrest in Caenorhabditis Elegans

Description: It was hypothesized that chronic hypoxia will affect various biological processes including developmental trajectory and behavior. To test this hypothesis, embryos were raised to adulthood in severe hypoxic environments (0.5% O2 or 1% O2, 22°C) and analyzed for survival rate, developmental progression, and altered behaviors. Wildtype hermaphrodites survive chronic hypoxia yet developmental trajectory is slowed. The hermaphrodites raised in chronic hypoxia had different phenotypes in comparison… more
Date: August 2011
Creator: Little, Brent Ashley
Item Type: Refine your search to only Thesis or Dissertation
open access

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
open access

Molecular Basis of Plant Defense Against Aphids: Role of the Arabidopsis Thaliana PAD4 and MPL1 Genes

Description: Myzus persicae (Sülzer), commonly known as green peach aphid (GPA), utilizes its slender stylet to penetrate the plant tissues intercellularly and consume copious amounts of photoassimilates present in the phloem sap causing extensive damage to host plants. The compatible interaction between GPA and Arabidopsis thaliana enabled us to characterize plant response to aphid infestation. Upon GPA infestation, Arabidopsis PAD4 (PHYTOALEXIN DEFICIENT4) gene modulates premature leaf senescence, which i… more
Date: August 2011
Creator: Louis, Joe
Item Type: Refine your search to only Thesis or Dissertation
open access

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
open access

Stress Response by Alternative σ-factor, RpoH, and Analysis of Posttranslational Modification of the Heat Shock Protein, Dnak, in Escherichia coli

Description: Bacteria have developed specialized responses that involve the expression of particular genes present in a given regulon. Sigma factors provide regulatory mechanisms to respond to stress by acting as transcriptional initiation factors. This work focuses on σ32 during oxidative stress in Escherichia coli. The differential response of key heat shock (HS) genes was investigated during HS and oxidative stress using qPCR techniques. While groEL and dnaJ experienced increases in transcriptional respo… more
Date: May 2015
Creator: Martinez, Sarah N.
Item Type: Refine your search to only Thesis or Dissertation
open access

Map-based cloning of the NIP gene in model legume Medicago truncatula.

Description: Large amounts of industrial fertilizers are used to maximize crop yields. Unfortunately, they are not completely consumed by plants; consequently, this leads to soil pollution and negative effects on aquatic systems. An alternative to industrial fertilizers can be found in legume plants that provide a nitrogen source that is not harmful for the environment. Legume plants, through their symbiosis with soil bacteria called rhizobia, are able to reduce atmospheric nitrogen into ammonia, a biologic… more
Date: May 2007
Creator: Morris, Viktoriya
Item Type: Refine your search to only Thesis or Dissertation
open access

9-Lipoxygenase Oxylipin Pathway in Plant Response to Biotic Stress

Description: The activity of plant 9-lipoxygenases (LOXs) influences the outcome of Arabidopsis thaliana interaction with pathogen and insects. Evidence provided here indicates that in Arabidopsis, 9-LOXs facilitate infestation by Myzus persicae, commonly known as the green peach aphid (GPA), a sap-sucking insect, and infection by the fungal pathogen Fusarium graminearum. in comparison to the wild-type plant, lox5 mutants, which are deficient in a 9-lipoxygenase, GPA population was smaller and the insect sp… more
Date: May 2012
Creator: Nalam, Vamsi J.
Item Type: Refine your search to only Thesis or Dissertation
open access

Molecular cloning and analysis of the genes for cotton palmitoyl-acyl carrier protein thioesterase (PATE) and Δ-12 fatty acid desaturase (FAD2-3) and construction of sense and anti-sense PATE plasmid vectors for altering oilseed composition of transgenic cotton plants.

Description: A cotton PATE cDNA clone has a 1.7-kb insert with an coding region for 410 amino acids, lacking codons for the three N-terminal amino acids. The predicted amino acid sequence of the PATE preprotein has a characteristic stromal-targeting domain and a 63% identity to the Arabidopsis FatB1 thioesterase sequence. A cotton genomic clone containing a 17.4-kb DNA segment was found to encompass a palmitoyl-ACP thioesterase (FatB1) gene. The gene spans 3.6 kb with six exons and five introns. The six… more
Date: May 2002
Creator: Nampaisansuk, Mongkol
Item Type: Refine your search to only Thesis or Dissertation
open access

Investigating the Ability of Pseudomonas aeruginosa pyrE Mutants to Grow and Produce Virulence Factors

Description: Pseudomonas aeruginosa are medically important bacteria that are notorious for causing nosocomial infections. To gain more knowledge into understanding how this organism operates, it was decided to explore the pyrimidine biosynthetic pathway. Pyrimidine synthesis, being one half of the DNA structure, makes it a very important pathway to the organism’s survivability. With previous studies being done on various genes in the pathway, pyrE has not been studied to the fullest extent. To study the fu… more
Date: December 2014
Creator: Niazy, Abdurahman
Item Type: Refine your search to only Thesis or Dissertation
open access

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
Item Type: Refine your search to only Thesis or Dissertation
open access

Comparison of Aspartate Transcarbamoylase Activity Between Pseudomonas Aeruginosa Which Has One Chromosome and Burkholderia Cepacia Which Has Three Chromosomes

Description: The pyrimidine biosynthetic pathway is essential and similar in all bacteria. The pathway from Pseudomonas is regulated by nucleotides which bind to the upstream region of the pyrBC’ gene complex. Work in our lab mapped the genes and showed that the pyrB and pyrC’ were part of an overlap complex. The Pseudomonas aeruginosa has one circular chromosome. A former Pseudomonas now called Burkholderia cepacia is similar to P. aeruginosa except that it contains three circular chromosomes (CI, CII, … more
Date: August 2012
Creator: Nusair, Arwa Y.
Item Type: Refine your search to only Thesis or Dissertation
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