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Genomic and Co-expression Analyses Predict Multiple Genes Involved in Triterpene Saponin Biosynthesis in Medicago truncatula

Description: Article discusses genomic and coexpression analyses predicting multiple genes involved in triterpene saponin biosynthesis in Medicago truncatula.
Date: March 9, 2010
Creator: Naoumkina, Marina A.; Modolo, Luzia V.; Huhman, David; Urbanczyk-Wochniak, Ewa; Tang, Yuhong; Sumner, Lloyd W. et al.
Partner: UNT College of Arts and Sciences

Studies on carotenoid biosynthesis and carotenoproteins of Corynebacterium poinsettiae ATCC 9682

Description: Thin layer chromatography and high performance liquid chromatography were used to compare pigments of the wild type streptomycin resistant strain of C. poinsettiae with those of mutants derived from it. Possible biosynthetic pathways in carotenoid biosynthesis of the wild type were postulated on the basis of observed blocks in pigment synthesis.
Date: August 1983
Creator: Wariso, Benjamin A.
Partner: UNT Libraries

Isolation and Partial Characterization of Pigment Mutants of Corynebacterium poinsettie ATCC 9682

Description: Carotenoid pigments were extracted from Corynebacteriuma poinsettiae (wild type) ATCC 9682, and from 108 mutants obtained by exposure of a streptomycin resistant strain of C. poinsettiae to ultra-violet light irradiation and N-methyl- N'-nitro-N-nitrosoguanidine. The pigments were characterized by their absorption maxima, Rf-values, and partition ratios in petroleum ether and methanol. Thin layer chromatography was used to compare pigments of the wild type with those of the mutants. Possible biosynthetic pathways in carotenoid synthesis of the wild type were postulated on the basis of the observed genetic blocks. Mutants were found which suggested the existence of a linear pathway in carotenoid synthesis from the aliphatic C4 0 molecule to the bi-cyclic C50-diol. Other mutants suggested possible alternative pathways in the biosynthesis of these pigments or the presence of intermediates not detectable by thin layer chromatography.
Date: August 1980
Creator: Wariso, Benjamin A.
Partner: UNT Libraries

The Magnesium Chelation Step in Chlorophyll Biosynthesis

Description: The progress described in this report encompasses work supported by DOE grant DE-FG09-89ER13989 for the period 2/15/92 to the present 6/14/94. The goals of the project were to continue investigating the enzymology of Mg-chelatase and to investigate the co-regulation of heme and chlorophyll formation in intact plastids. During this period the laboratory had additional support (two years) from USDA to investigate heme metabolism in chloroplasts. This report is arranged so that the progress is described by reference to manuscripts which are published, under review or in preparation.
Date: January 17, 2001
Creator: Dilworth, Gregory L.
Partner: UNT Libraries Government Documents Department

Glucose or Altered Ceramide Biosynthesis Mediate Oxygen Deprivation Sensitivity Through Novel Pathways Revealed by Transcriptome Analysis in Caenorhabditis elegans

Description: This article discusses how RNA-sequencing analysis was performed to assess how a glucose-supplemented diet and/or a hyl-2 mutation altered the transcriptome.
Date: August 5, 2016
Creator: Ladage, Mary L.; King, Skylar D.; Burks, David J.; Quan, Daniel L.; Garcia, Anastacia M.; Azad, Rajeev K. et al.
Partner: UNT College of Arts and Sciences

Genomic Characterization of Methanomicrobiales Reveals Three Classes of Methanogens

Description: Methanomicrobiales is the least studied order of methanogens. While these organisms appear to be more closely related to the Methanosarcinales in ribosomal-based phylogenetic analyses, they are metabolically more similar to Class I methanogens. In order to improve our understanding of this lineage, we have completely sequenced the genomes of two members of this order, Methanocorpusculum labreanum Z and Methanoculleus marisnigri JR1, and compared them with the genome of a third, Methanospirillum hungatei JF-1. Similar to Class I methanogens, Methanomicrobiales use a partial reductive citric acid cycle for 2-oxoglutarate biosynthesis, and they have the Eha energy-converting hydrogenase. In common with Methanosarcinales, Methanomicrobiales possess the Ech hydrogenase and at least some of them may couple formylmethanofuran formation and heterodisulfide reduction to transmembrane ion gradients. Uniquely, M. labreanum and M. hungatei contain hydrogenases similar to the Pyrococcus furiosus Mbh hydrogenase, and all three Methanomicrobiales have anti-sigma factor and anti-anti-sigma factor regulatory proteins not found in other methanogens. Phylogenetic analysis based on seven core proteins of methanogenesis and cofactor biosynthesis places the Methanomicrobiales equidistant from Class I methanogens and Methanosarcinales. Our results indicate that Methanomicrobiales, rather than being similar to Class I methanogens or Methanomicrobiales, share some features of both and have some unique properties. We find that there are three distinct classes of methanogens: the Class I methanogens, the Methanomicrobiales (Class II), and the Methanosarcinales (Class III).
Date: May 1, 2009
Creator: Anderson, Iain; Ulrich, Luke E.; Lupa, Boguslaw; Susanti, Dwi; Porat, Iris; Hooper, Sean D. et al.
Partner: UNT Libraries Government Documents Department

Identification and Characterization of the Pyrimidine Biosynthetic Operon in Streptomyces griseus

Description: To further understand the ATCase/DHOase bifunctional complex formed in Streptomyces, the genes encoding these and other pyrimidine enzymes were identified and characterized. Polymerase chain reaction (PCR) was utilized in this effort. Primers were constructed by selecting conserved regions of pyrimidine genes from known gene and protein sequences of a wide variety of organisms. These sequences were then optimized to Streptomyces codon usage. PCR products were obtained from internal sites within pyrimidine genes and also from primer combinations of different genes. The size, orientation, and partial sequence of the resulting products shows that Streptomyces has a gene organization of pyrR followed by pyrB, pyrC, carA, carB, and pyrF in an operon similar to that found in other Gram-positive bacteria.
Date: May 1998
Creator: Hooten, Jody J. (Jody Jeran)
Partner: UNT Libraries

Investigation of Pyrimidine Salvage Pathways to Categorize Indigenous Soil Bacteria of Agricultural and Medical Importance and Analysis of the Pyrimidine Biosynthetic Pathway's Enzyme Properties for Correlating Cell Morphology to Function in All Phases of Growth

Description: This dissertation comprises three parts and is presented in two chapters. Chapter 1 concerns Arthrobacter, a bacterium with an intriguing growth cycle. Whereas most bacteria exist as either a rod or coccus, this bacterium shares the rod/coccus lifestyle. It therefore seemed important to examine the growth regulatory pathways from the rod and coccus. The committed step, that catalyzed by aspartate transcarbamoylase (ATCase), in the pyrimidine biosynthetic pathway was chosen. The ATCase in Arthrobacter is like the well known Pseudomonas enzyme except that it has an active dihydroorotase (DHOase) associated. Included in Chapter 1 is the description of a microorganism, Burkholderia cepacia, whose ATCase has characteristics that are at once reminiscent of bacteria, mammals, and fungi. It differs in size or aggregation based on environmental conditions. In addition, it has an active DHOase associated with the ATCase, like Arthrobacter. B. cepacia is important both medically and for bioremediation. Since B. cepacia is resistant to most antibiotics, its unique ATCase is a prime target for inhibition. Whereas the first chapter deals with the de novo pathway to making pyrimidines, which is found mainly in the lag and log phase, Chapter 2 addresses the salvage pathway, which comes more into play during the stationary phase. This section focuses on the isolation, identification, and grouping of a number of natural soil bacteria from various soil locations. These organisms are important agriculturally, medically, and industrially. Addition of these soil isolates to poor soils has been found to improve the soil. In a previous study by D.A. Beck, the salvage schemes for a number of laboratory strains of microorganisms were determined. Nine separate classes of salvage were designated by determining the salvage enzymes present. In this study emphasis has been placed on soil bacteria, which had not previously been analyzed. A number of species of soil ...
Date: May 2003
Creator: Meixner, Jeffery Andrew
Partner: UNT Libraries

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, which are known to modify the Gᵢ and Gₛ proteins respectively, thus activating adenylate cyclase to release more cAMP. The toxin inactivation can be prevented by inhibitors of the ADP-ribosylation such as, benzamide and MBAMG. Addition of dibutyryl-cAMP inhibits the IL-1 induced CSF production. Both Theophylline and Forskolin which increase cAMP by inhibiting phosphodiesterase and stimulating adenylate cyclase respectively, also inhibit CSF-1 production. Results from these studies have shown that cAMP level inversely regulates the biosynthesis of CSF-1. Preincubation of MIA PaCa-2 cells with IL-1 and 5'- guanylylimidodiphosphate (GppNHp) prevents the inhibitory effect of pertussis toxin on CSF-1 production. These data are consistent with the hypothesis that IL-1 binds to its receptor and couples to Gᵢ∝ resulting in the inhibition of adenylate cyclase and reducing cAMP level. Lowering of the' cAMP level leads to the activation of CSF-1 gene expression. The activity of another inducer of CSF-1 production in this system, 12-0-tetradecanoylphorbol-13-acetate (TPA), can be abolished by 1- (5-isoquinolinesulfonyl)-2-methylpiperazine dihydrochloride (H-7), which is a specific inhibitor of protein kinase C. However, H-7 failed to inhibit IL-1 stimulated CSF-1 production. Other known activators of protein kinase C namely, Ca²⁺ and L-α-l-oleoyl-2-acetoyl-sn- 3-glycerol (OAG), also increase CSF production. On the other hand, Indomethacin which is known to inhibit prostaglandin E (PGE), stimulates CSF-1 production in MIA PaCa-2 cells. These data suggest that different mechanisms ...
Date: May 1990
Creator: Ku, Chun-Ying
Partner: UNT Libraries

The Calyptogena magnifica chemoautotrophic symbiont genome

Description: Chemoautotrophic endosymbionts are the metabolic cornerstone of hydrothermal vent communities, providing invertebrate hosts with nearly all of their nutrition. The Calyptogena magnifica (Bivalvia: Vesicomyidae) symbiont, Candidatus Ruthia magnifica, is the first intracellular sulfur-oxidizing endosymbiont to have its genome sequenced, revealing a suite of metabolic capabilities. The genome encodes major chemoautotrophic pathways as well as pathways for biosynthesis of vitamins, cofactors, and all 20 amino acids required by the clam.
Date: March 1, 2007
Creator: Newton, I.L.; Woyke, T.; Auchtung, T.A.; Dilly, G.F.; Dutton,R.J.; Fisher, M.C. et al.
Partner: UNT Libraries Government Documents Department

The PanK2 Genes of Mouse and Human Specify Proteins with DistinctSubcellular Locations

Description: Coenzyme A (CoA) biosynthesis is initiated by pantothenatekinase (PanK) and CoA levels are controlled through differentialexpression and feedback regulation of PanK isoforms. PanK2 is amitochondrial protein in humans, but comparative genomics revealed thatacquisition of a mitochondrial targeting signal was limited to primates.Human and mouse PanK2 possessed similar biochemical properties, withinhibition by acetylCoA and activation by palmitoylcarnitine. Mouse PanK2localized in the cytosol, and the expression of PanK2 was higher in humanbrain compared to mouse brain. Differences in expression and subcellularlocalization should be considered in developing a mouse model for humanPanK2 deficiency. (c) 2007 Federation of European Biochemical Societies.Published by Elsevier B.V.
Date: May 1, 2007
Creator: Leonardi, Roberta; Zhang, Yong-Mei; Lydikis, Athanasios; Stevens,Robert D.; Ilkayeva, Olga R.; Wenner, Brett R. et al.
Partner: UNT Libraries Government Documents Department