Biochemistry, Biophysics, and Structural Biology Commons^™

The Characterization Of A Novel Petite Phenotype In Transgenic Arabidopsis Thaliana And The Examination Of The Expression Patterns Of A Gamma Carbonic Anhydrase Homologue In Arabidopsis Thaliana, Sumeet K. Asrani

Honors Capstones

No abstract provided.

Evidence For Two Mechanisms Of Amino Acid Osmolyte Release From Hippocampal Slices, R. Franco, M. E. Torres-Marquez, H. Pasantes-Morales

School of Veterinary and Biomedical Sciences: Faculty Publications

A 30% decrease in osmolarity stimulated ³H-taurine, ³H-GABA and glutamate (followed as ³H-D-aspartate) efflux from rat hippocampal slices. ³H-taurine efflux was activated rapidly but inactivated slowly. It was decreased markedly by 100 μM 5-nitro-(3-phenylpropylamino) benzoic acid (NPPB) and 600 μM niflumic acid and inhibited strongly by tyrphostins AG18, AG879 and AG112 (25–100 μM), suggesting a tyrosine kinase-mediated mechanism. Hyposmolarity activated the mitogen-activated protein kinases (MAPK) extracellular-signal-related kinase-1/2 (ERK1/ERK2) and p38, but blockade of this reaction did not affect ³H-taurine efflux. Hyposmosis also activated phosphatidyl-inositide 3-kinase (PI3K) and its prevention by wortmannin (100 nM) essentially abolished …

The Examination Of The Expression Patterns Of A Gamma Carbonic Anhydrase Homologue In Arabidopsis Thaliana, Eric Thomas Dane Nielsen Iii

Honors Capstones

No abstract provided.

Detection Of Aneuploidy For Chromosomes 7 And 8 Using Fluorescence In Situ Hybridization In Patients With Aplastic Anemia And Sequencing Of The Mitotic Checkpoint Gene Hbub1, Laura Jane Aridgides

Theses and Dissertations in Biomedical Sciences

Aplastic anemia (AA) is characterized by complete bone marrow failure. Progression to myelodysplastic syndromes (MDS) and acute nonlymphocytic leukemia (ANLL) occurs frequently. At the time of transformation, cytogenetic abnormalities are common. Detection of cytogenetic abnormalities prior to leukemic transformation may indicate future disease progression. Karyotype analysis is the current method of choice to evaluate chromosome aberrations. However, fluorescence in situ hybridization (FISH) is more sensitive in detecting these abnormalities.

hBUB1, a mitotic spindle checkpoint gene, was shown to be mutated in two colorectal cancer cell lines with high levels of aneuploidy (Cahill, et al., 1998). Although theoretically possible, conclusive …

Phase Modulation At 125 Khz In A Michelson Interferometer Using An Inexpensive Piezoelectric Stack Driven At Resonance, Barbara M. Hoeling, Andrew D. Fernandez, Richard C. Haskell, Daniel C. Petersen

All HMC Faculty Publications and Research

Fast phase modulation has been achieved in a Michelson interferometer by attaching a lightweight reference mirror to a piezoelectric stack and driving the stack at a resonance frequency of about 125 kHz. The electrical behavior of the piezo stack and the mechanical properties of the piezo-mirror arrangement are described. A displacement amplitude at resonance of about 350 nm was achieved using a standard function generator. Phase drift in the interferometer and piezo wobble were readily circumvented. This approach to phase modulation is less expensive by a factor of roughly 50 than one based on an electro-optic effect.

Structural Studies Of Scallop Abductin, A Compressible Elastomer That Translates Hydrophobic Interactions To Elasticity, Felipe Jimenez Jr.

Loma Linda University Electronic Theses, Dissertations & Projects

Abductin is a natural elastomer found as the major component of the elastic hinge ligament in marine scallops. Until now, very little was known about the structure and function of this compressible elastomer. Biochemical studies of a synthetic 25 amino acid peptide of abductin produces fibers that assemble into a gel matrix at room temperature. Further investigation of this phenomenon via temperature-dependent turbidimetry revealed that this peptide self-assembles or aggregates at 23 °C. Secondary structural studies of this peptide at different temperatures revealed that it undergoes an inverse temperature transition much like soluble elastin peptides. Replacing phenylalanine with alanine in …

Plant-Based Multicomponent Vaccines Against Enteric Diseases, Jie Yu

Loma Linda University Electronic Theses, Dissertations & Projects

To generate a plant-based multicomponent oral vaccine against cholera, rotavirus and enterotoxigenic E.coli (ETEC), we have constructed transgenic potato plants that synthesize the cholera toxin B and A2 subunits, the rotavirus enterotoxin NSP4 22 amino acid epitope and the ETEC fimbrial antigen CFA/L To use cholera toxin as a carrier molecule for delivery of multiple antigens to the gut-associated lymphoid tissues, the rotavirus NSP4 epitope was linked to the cholera toxin B subunit (CTB) and the ETEC fimbrial antigen CFA/I was linked to the cholera toxin A2 subunit. Cholera toxin-antigen fusion proteins were detected in transformed tuber tissues by immunoblot …

Nuclear Export Of 60s Ribosomal Subunits Depends On Xpo1p And Requires A Nuclear Export Sequence-Containing Factor, Nmd3p, That Associates With The Large Subunit Protein Rpl10p, Olivier Gadal, Daniela Strau, Jacques Kessl, Bernard Trumpower

Dartmouth Scholarship

Nuclear export of ribosomes requires a subset of nucleoporins and the Ran system, but specific transport factors have not been identified. Using a large subunit reporter (Rpl25p-eGFP), we have isolated several temperature-sensitive ribosomal export (rix) mutants. One of these corresponds to the ribosomal protein Rpl10p, which interacts directly with Nmd3p, a conserved and essential protein associated with 60S subunits. We find that thermosensitive nmd3 mutants are impaired in large subunit export. Strikingly, Nmd3p shuttles between the nucleus and cytoplasm and is exported by the nuclear export receptor Xpo1p. Moreover, we show that export of 60S subunits is Xpo1p dependent. We …

Heterogeneity Within Animal Thioredoxin Reductases, Qi-An Sun, Francesca Zappacosta, Valentina M. Factor, Peter J. Wirth, Dolph L. Hatfield, Vadim N. Gladyshev

Vadim Gladyshev Publications

Animal thioredoxin reductases (TRs) are selenocysteine- containing flavoenzymes that utilize NADPH for reduction of thioredoxins and other protein and nonprotein substrates. Three types of mammalian TRs are known, with TR1 being a cytosolic enzyme, and TR3, a mitochondrial enzyme. Previously characterized TR1 and TR3 occurred as homodimers of 55–57-kDa subunits. We report here that TR1 isolated from mouse liver, mouse liver tumor, and a human T-cell line exhibited extensive heterogeneity as detected by electrophoretic, immunoblot, and mass spectrometry analyses. In particular, a 67-kDa band of TR1 was detected. Furthermore, a novel form of mouse TR1 cDNA encoding a 67-kDa selenoprotein …

Induction Of White Cell Proliferation Due To Haematopoietic Growth Factors Is Associated With An Increase In Multiple Forms Of Dihydrofolate Reductase In Non-Neutropenic Cancer Patients, M P. Iqbal, I A. Burney, F Sultana, N Mehboobali

Department of Biological & Biomedical Sciences

Objective: Granulocyte-colony stimulating factor (G-CSF) and granulocyte macrophage-colony stimulating factor (GM-CSF) are frequently used in cancer patients to overcome the granulocytopenic effects of chemotherapy, and also to mobilize the stem cells. The mobilized stem cells are collected from the peripheral blood and used for transplantation following high doses of chemotherapy. However, the molecular mechanism by which these colony stimulating factors (CSFs) bring about proliferation of myeloid precursor cells is not clearly known. Dihydrofolate reductase (DHFR), which has an established role in DNA synthesis, could be a link between administration of CSF and stem cell proliferation. The purpose of this study …

Process For Immobilizing Waste Using Bagasse (Us Patent 6174275), Michael A. Janusa

Faculty Publications

No abstract provided.

Genomic Diversity Of Pseudomonas Aeruginosa In Cystic Fibrosis, Nathaniel Edwards Head

Theses, Dissertations and Capstones

Pseudomonas aeruginosa is a common environmental microorganism. However, it has the genetic capacity to cause diseases in patients with compromised host defense systems. Cystic fibrosis (CF) is one of the major hereditary diseases among Caucasian populations. CF patients are born with a defective chloride channel that is responsible for maintaining fluid and electrolyte balance across the lumen of the lung. This imbalance leads to the production of an abnormal dehydrated viscous mucous, prohibiting the patient from normally clearing the respiratory airway. Chronic pulmonary infections with P. aeruginosa are the major causes of high morbidity and mortality in CF. Two of …

Methods Development For The Identification Of Unknown Proteins, Laura Brumfield Neal

Theses, Dissertations and Capstones

The chemistry of transport, storage, energy production, and reproduction in physiological systems is controlled by the actions and interactions of proteins. A species full complement of these amazing machines is often referred to as its proteome. The new science of proteomics utilizes a set of powerful and evolving tools to characterize the nature of the proteome, and further to fully elucidate the functional attributes of the proteins and their associations.

A methodology was developed by combining several proteomic techniques, such as electrophoresis, RP-HPLC, and mass spectrometry, to correctly identity proteins. Three known proteins (myoglobin, albumin, and actin) were employed for …

Characterization And Regulation Of Skn-Directed Autoimmune Skin Lesions, Pamela Jane Staton

Theses, Dissertations and Capstones

In the Skn model of autoimmunity, pathogenic T cells sensitized to Skn epidermal antigens (Skn-immune spleen cells or SIS cells) elicited disease in the form of skin lesions when adoptively transferred into shaved immunoincompetent syngeneic adult recipients (‘lesion-forming animals’) while concomitant injection of immunoregulatory normal spleen cells at twice the concentration (2 x normal spleen cells or 2XNS cells) of SIS cells significantly lessened lesion development (‘lesion-controlling animals’) by Day 7 post cell transfer. In a time-course RT-PCR cytokine analysis of skin from lesion-forming and lesion-controlling animals, IL-7 mRNA was significantly elevated in lesion-controlling skin on Day 7 while no …

The Algebraic Application Of Lewis Structures In Conjunction With Combinatorial Analysis In Global Molecular Identification From Graphs, Jonathan Geach

Capstone Research Projects

Closed shell bonding can be described by a theory that relates the manner that atoms fill their outer shells to algebraic formulas. Equations can be derived that are capable of deciding whether a given electron configuration gives a closed shell electron structure or not. A combinatorial analysis can be used to try every possible electron configuration for a given structure. The equations are then used to determine whether each structure gives a closed shell electron configuration. Some of these molecules may be considered impossible because they are bonded to noble gases. However, a list of molecules that contain a noble …

Antifungal Activity Of Substituted 8-Quinolinol-5- And 7-Sulfonic Acids: A Mechanism Of Action Is Suggested Based On Intramolecular Synergism / Hermon Gershon, Muriel Gershon, & Donald D. Clarke Harding Laboratory, The New York Botanical Garden, Bronx, New York 10458, Usa; Department Of Chemistry, Fordham University, Bronx, New York 10458, Usa, Herman Gershon, Muriel Gershon, Donald Dudley Clarke Phd

Chemistry Faculty Publications

8-Quinolinol-5-sulfonic acid was nearly devoid of antimicrobial activity, due to what was believed to be an unfavorable partition coefficient. Since twenty six 8-quinolinol-5- and 7 -sulfonic acids were available from our previous work, they were tested against six fungi. The 7 -chloro and 7 -bromo-5-sulfonic acids and the 5-chloro and 5-bromo-7 -sulfonic acids showed fungal inhibition within one order of magnitude of that of 8-quinolinol. It is suggested that a nonchelating mechanism is in part responsible for this fungitoxicity. Five additional 5-sulfonic acids with chlorine in positions 3-, 6-, 3,6-, 3,7-, and 6,7- that were suitable for studies in synergism …

Preparation And Fungitoxicity Of Some Trichloro-, Tribromo-, Tetrachloro-, And Tetrabromo-8-Quinolinols / Herman Gershon, Donald D. Clarke, And Muriel Gershon Department Of Chemistry, Fordham University, Bronx, New York 10458-9993 Usa, New York Botanical Garden, Bronx, New York 10458-9993 Usa, Herman Gershon, Donald Dudley Clarke Phd, Muriel Gershon

Chemistry Faculty Publications

3,5,6-, 3,5,7-, 4,5,7-, and 5,6,7-trichloro- and -tribromo-8-quinolinols as well as 3,5,6,7- tetrachloro- and -tetrabromo-8-quinolinols were prepared and tested against six fungi (Aspergillus niger, Aspergillus oryzae, Myrothecium verrucaria, Trichoderma viride, Mucor cirinelloides, and Trichophyton mentagrophytes) in Sabouraud dextrose broth. The compounds strongly inhibit five fungi but not M. cirinelloides. They are less active than the related dichloro-8-quinolinols which is attributed to steric hindrance

Cloning And Expression Analysis Of Hemoglobin Genes From Maize (Zea Mays Ssp. Mays) And Teosinte (Zea Mays Ssp. Parviglumis), Elena Aréchaga-Ocampo, Juan Saenz-Rivera, Gautam Sarath, Robert V. Klucas, Raúl Arredondo-Peter

Gautam Sarath Publications

With the exception of barley and rice, little is known about the existence of hemoglobins (Hbs) in cereals. This work reports the cloning and analysis of hb genes from maize (Zea mays ssp. mays) and teosinte (Zea mays ssp. parviglumis). Coding sequences of maize and teosinte hb genes (hbm and hbt, respectively) are highly similar to each other and are interrupted by three introns located at identical positions as other plant hb genes. Sequences of predicted Hbm and Hbt proteins are identical. The hydropathic profile of Hbm and Hbt is highly similar to that …

Effect Of Forskolin On Actin Polymerization In Cultured Vascular Smooth Muscle, Mary Janay Bailey

Theses, Dissertations and Capstones

Increases in intracellular cyclic AMP levels have been shown to affect vascular smooth muscle morphology. In the present study, effects of elevated cyclic AMP levels on actin polymerization were assessed to determine whether cyclic AMP induces specific changes in cytoskeletal proteins of vascular smooth muscle cells. Forskolin was used to increase intracellular cyclic AMP levels through direct activation of adenylate cyclase. Light and Electron microscopy was employed to appraise changes in the shape of vascular smooth muscle cells. Confocal microscopy was used to reveal cytoskeletal changes after exposure to M forskolin for increasing intervals of time. Differences in the expression …

Voltage Gating Of A Model Membrane Spanning Channel, Eric Miller

Inquiry: The University of Arkansas Undergraduate Research Journal

Channels in cell membranes are important for intercellular communication and especially for the function of the nervous system in higher vertebrates. These channels consist of proteins made from the 20 common amino acids. Channel proteins are embedded into the lipid bilayer membranes of living cells and function by allowing the specific passage of a positively charged material such as sodium or potassium ions across the membrane in response to an external signal. The external signaloeither a chemical signal or a voltageoregulates the opening and closing of channels. In an attempt to understand the voltage-dependent opening of channels (igatingi), we are …

X-Ray Diffraction Structures Of Some Phosphatidylethanolamine Lamellar And Inverted Hexagonal Phases, Paul E. Harper, David A. Mannock, Ruthven Lewis, Ronald N. Mcelhaney

University Faculty Publications and Creative Works

X-ray diffraction is used to solve the low-resolution structures of fully hydrated aqueous dispersions of seven different diacyl phosphatidylethanolamines (PEs) whose hydrocarbon chains have the same effective chain length but whose structures vary widely. Both the lower-temperature, liquid-crystalline lamellar (Lα) and the higher-temperature, inverted hexagonal (H11) phase structures are solved, and the resultant internal dimensions (d-spacing, water layer thickness, average lipid length, and headgroup area at the lipid-water interface) of each phase are determined as a function of temperature. The magnitude of the Lα and H11 phase d-spacings on either side of the Lα/H11 phase transition temperature (Tη) depends significantly …

Cationic Surfactant Mediated Hybridization And Hydrophobization Of Dna Molecules At The Liquid/Liquid Interface And Their Phase Transfer, Murali Sastry, Ashavani Kumar, Mrunalini Pattarkine, Vidya Ramakrishnan, Krishna N. Ganesh

Faculty Works

Hybridization of complementary oligonucleotides mediated by a cationic surfactant at the water/hexane interface leads to hydrophobic, double-helical DNA which may be readily phase transferred to the organic phase and cast into thin films on solid substrates.

A Crystallographic Map Of The Transition From B-Dna To A-Dna, Jeff Vargason, Keith Henderson, P. Shing Ho

Faculty Publications - Department of Biological & Molecular Science

No abstract provided.

C3 Origins Of The C4 Pathway Regulatory Enzyme, Ppdk-Rp, C. J. Chastain, Gautam Sarath, Raymond Chollet

Gautam Sarath Publications

A current view of C₄ and CAM evolution holds that all of the constituent enzymes of the C₄ pathway preexisted in C₃ plants, albeit functioning in nonphotosynthetic capacities.

The Wasp-Like Protein Scar Regulates Macropinocytosis, Phagocytosis And Endosomal Membrane Flow In Dictyostelium, David J. Seastone, Ed Harris, Lesly A. Temesvari, James E. Bear, Charles L. Saxe, James Cardelli

Department of Biochemistry: Faculty Publications

Scar, a member of the WASp protein family, was discovered in Dictyostelium discoideum during a genetic screen for second-site mutations that suppressed a developmental defect. Disruption of the scar gene reduced the levels of cellular F-actin by 50%. To investigate the role of Scar in endocytosis, phagocytosis and endocytic membrane trafficking, processes that depend on actin polymerization, we have analyzed a Dictyostelium cell line that is genetically null for Scar. Rates of fluid phase macropinocytosis and phagocytosis are significantly reduced in the scar^- cell-line. In addition, exocytosis of fluid phase is delayed in these cells and movement of fluid …

Rab11-Like Gtpase Associates With And Regulates The Structure And Function Of The Contractile Vacuole System In Dictyostelium, Ed Harris, Kunito Yoshida, James Cardelli, John Bush

Department of Biochemistry: Faculty Publications

Screening of a cDNA library revealed the existence of a Dictyostelium cDNA encoding a protein 80% identical at the amino acid level to mammalian Rab11. Subcellular fractionation and immunofluorescence studies revealed that DdRab11 was exclusively associated with the ATPase proton pump-rich contractile vacuole membrane system, consisting of a reticular network and bladder-like vacuoles. Video microscopy of cells expressing GFP-DdRab11 revealed that this Rab was associated with contractile vacuolar bladders undergoing formation, fusion and expulsion of water. The association of DdRab11 with contractile vacuole membranes was disrupted when cells were exposed to either hypo-osmotic conditions or an inhibitor of the ATPase …

The Cia5 Gene Controls Formation Of The Carbon Concentrating Mechanism In Chlamydomonas Reinhardtii, Youbin Xiang, Jun Zhang, Donald P. Weeks

Department of Biochemistry: Faculty Publications

Wild-type Chlamydomonas reinhardtii cells shifted from high concentrations (5%) of CO2 to low, ambient levels (0.03%) rapidly increase transcription of mRNAs from several CO₂-responsive genes. Simultaneously, they develop a functional carbon concentrating mechanism that allows the cells to greatly increase internal levels of CO₂ and HCO₃. The cia5 mutant is defective in all of these phenotypes. A newly isolated gene, designated Cia5, restores transformed cia5 cells to the phenotype of wild-type cells. The 6,481-bp gene produces a 5.1-kb mRNA that is present constitutively in light in high and low CO₂ both in …

Selenoprotein Oxidoreductase With Specificity For Thioredoxin And Glutathione Systems, Qi-An Sun, Leo Kirnarsky, Simon Sherman, Vadim N. Gladyshev

Department of Biochemistry: Faculty Publications

Thioredoxin (Trx) and glutathione (GSH) systems are considered to be two major redox systems in animal cells. They are reduced by NADPH via Trx reductase (TR) or oxidized GSH (GSSG) reductase and further supply electrons for deoxyribonucleotide synthesis, antioxidant defense, and redox regulation of signal transduction, transcription, cell growth, and apoptosis. We cloned and characterized a pyridine nucleotide disulfide oxidoreductase, Trx and GSSG reductase (TGR), that exhibits specificity for both redox systems. This enzyme contains a selenocysteine residue encoded by the TGA codon. TGR can reduce Trx, GSSG, and a GSH-linked disulfide in in vitro assays. This unusual substrate specificity …

Effects Of Antimetabolites On Sclerotium Rolfsii Growth And Oxalic Acid Production, Ezikiel Okafor-Agilo

Seton Hall University Dissertations and Theses (ETDs)

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Nitric Oxide Mediated Effect Of Cyclo-Oxygenase Inhibitors, M Mahmood, H S. Zuberi, M K. Ashfaq

Department of Biological & Biomedical Sciences

Objectives: Non-Steroidal anti-inflammatory drugs (NSAIDS) have long been used as anti-inflammatory agents, yet their mode of action is not entirely clear. The inhibitory effects of NSAIDS on prostaglandin production can only partly explain their anti-inflammatory actions. This study was aimed at defining the role of cycl-oxygenase (COX) inhibitors on nitric oxide (NO) production in murine macrophages in vitro.
Methods: Murine macrophages were obtained from the peritoneum and after exposure, in vitro to lipopolysaccharide (LPS) produced nitrite, measured after 24 hours by Griess reaction. The macrophages were pre-incubated with aspirin or indomethacin before activation with LPS.
Results: Treatment with aspirin resulted …