WWW.DISSERTATION.XLIBX.INFO
FREE ELECTRONIC LIBRARY - Dissertations, online materials
 
<< HOME
CONTACTS



Pages:     | 1 |   ...   | 4 | 5 || 7 | 8 |   ...   | 112 |

«Strengthening the Nation through Diversity, Innovation & Leadership in STEM San Antonio,Texas · October 3-6, 2013 Get Connected! Connect with the ...»

-- [ Page 6 ] --

Amyloid fibrils have gained much attention recently within the scientific community. Amyloids are insoluble protein aggregates composed of polymerized cross-linked β sheets that are typically between 5 to 12 nm in width and have variable lengths. Amyolids have properties that make them ideal candidates for use in bionanotechnology, namely their exceptional strength, elasticity, and stability as well as their ability to self assemble. In particular, our research is interested in amyloids and their potential use in the assembly of hybrid peptide-polymer supramolecular nanostructures via noncovalent interactions. Studies are being carried out using KLVFFAE, the amyloidogenic peptide sequence of Aβ protein associated with Alzheimer’s disease. These studies focus on the effects of polyethylene glycol (PEG) modification on the amyloid self-assembly process: specifically, the modulation of nanostructures of varying sizes and configurations. Solid-phase synthesis has been used to prepare modified peptides that contain functional amino acids to enable site-specific PEGylation. Maldi-TOF was used to confirm the molecular weight of the synthesized peptides. Peptides were conjugated to PEG using carbodiimide or maleimide-thiol chemistry.

Self assembly of these conjugates into amyloid-like structures was investigated under varying temperature and shaking conditions. The resulting nanostructures were characterized using TEM and fluorescence spectroscopy.

Results indicate that the presence of PEG alters the properties of the peptide aggregates. While our initial goal is to investigate the self-assembly of hybrid bionanomaterials, we expect these efforts will contribute to a better understanding of the amyloidogenesis processes related to amyloid-related diseases and to the development of selfassembled biomaterials for various applications.

FRI-125

THE EFFECT OF SILVER NANOPARTICLES ON PLANT GROWTH PATTERNS

Cailin Jones1, Kwok-Tuen (Raymond) Tse2.

DePaul University, Chicago, IL, 2Harold Washington College, Chicago, IL.

1 Nanoparticles (NPs) are constantly consumed both voluntarily and involuntarily by living organisms and are used to make everyday products such as make up, medicines, and pesticides. Although bulk material (≥ 100 nm) and NPs ( 100 nm) are made from the same metal, NPs differ not only in size but chemical properties as well, which could pose a potential threat to an organism’s health. Metal NPs are insoluble and can easily enter a human’s body by inhalation, ingestion, or penetration through the skin. They travel through the blood stream and attach themselves to key organs. The proposed experiment entails preparing NPs and testing their effects on plant-life. It is hypothesized that silver nanoparticles (Ag-NP) will affect seed germination and growth patterns of a plant. The Ag-NPs will be

27 UNDERGRADUATE POSTER ABSTRACTS

prepared using chemical reduction to precipitate out the solid Ag-NPs. Radish and mustard-green seeds will be used for this experiment because they are easy to grow and will germinate within a short time. The seeds are cultivated in a Petri dish on a moist paper towel to observe germination rate. To analyze growth patterns, the seeds will be grown in soil and watered with water containing various concentrations of the Ag-NPs. Signs of plant abnormalities will help determine which concentration causes the most damage. The experiment with the plants has not been conducted yet, but silver nanoparticles have been successfully prepared.

SAT-119

CRYSTALLIZATION OF THE HETERODIMERIC 220KDA NUP84-NUP133 NUCLEAR PORE SCAFFOLDING UNIT

Marc Gancayco, Kevin Knockenhauer, Thomas Schwartz.

Massachusetts Institute of Technology, Cambridge, MA.

The nuclear pore complex (NPC) is a 40 to 60 MDa protein complex that coats circular openings in the nuclear envelope and serves as the main conduit for molecular transport into and out of the nucleus of the eukaryotic cell. In an effort to understand the atomic structure of the NPC, a divide-and-conquer strategy is applied. The entire NPC is a modular structure built from multiple copies of biochemically defined subassemblies that are individually amenable to structural characterization. The scaffold ring of the NPC coats the nuclear envelope and is characterized by two major subcomplexes: the heptameric Y- or Nup84-complex and the heteromeric Nic96 complex. The Y-complex has 7 universally conserved components: Nup84, Nup85, Nup120, Nup133, Nup145C, Sec13, and Seh1. Crystal structures of many Y-complex fragments are available, making it the best-characterized subcomplex of the NPC. Our work focused on solving the structure of the Nup84-Nup133 complex from yeast. The human homolog has already been characterized in part to high resolution and was used to model the interaction site for the yeast Nup84-Nup133 complex based on sequence conservation. Nup133 truncations were designed based on homology modeling to produce a minimal interacting complex ideal for crystallization. Full length Nup84 was coexpressed with truncations of Nup133 in E. coli. The complex was copurified via nickel affinity, ion exchange, and size-exclusion chromatography.

Crystallization studies are currently under way with the goal of completing a composite structure of the entire universally conserved heptameric Y-complex.





FRI-107

ER STRESS: A POSSIBLE MECHANISM FOR CLOZAPINE-INDUCED METABOLIC SYNDROME

Uche Ozoemena1, Dina Attia1, Consuelo Walss-Bass2, Veronica Contreras-Shannon1.

St. Mary’s University, San Antonio, TX, 2University of Texas, Health Science Center at San Antonio, San Antonio, TX.

1 The atypical,antipsychotic drug clozapine causes metabolic syndrome as a side effect in some patients. The mechanism through which these side effects come about is unknown. It has been suggested that clozapine could cause mitochondrial dysfunction and endoplasmic reticulum (ER) stress, both of which are known to cause metabolic syndrome. In this study, we are exploring the effects of clozapine on ER stress. We hypothesized that treating cells with clozapine would induce ER stress. The ER is responsible for proper folding and secretion of proteins in normal cellular conditions. Under stressful conditions, however, the ER may initiate the unfolded protein response (UPR) which is intended to minimize the production of misfolded or unfolded proteins. This is accomplished by changes in gene expression and cell death in extreme cases. To test our hypothesis, we measured the expression of ER stress response genes Gadd34, Chop10, and Hspa5 in cultured mouse adipocytes (3T3-L1), myoblasts (C2C12), and monocytes (RAW 264.7) treated with increasing concentrations of clozapine: 0, 25, 50, and 75 uM, for 24 hours.

After 24 hours, RNA was isolated for qRT-PCR. In 3T3 cells, increasing concentrations of clozapine led to significant upregulation of both Chop10 and Gadd34 genes (p values of 0.0199 and 0.0097, respectively). These initial results suggest that clozapine does cause ER stress, and this may be one mechanism by which clozapine causes its adverse effects.

FRI-117

CHARACTERIZATION OF CHEMOTAXIS CLUSTER EXPERIMENTS

Erenis Lemus1, Steve Smriga2.

University of California, Santa Barbara, Santa Barbara, CA, 2Massachusetts Institute of Technology, Cambridge, MA.

1 Microscale interactions among marine microbes drive carbon and nutrient cycles in the global ocean. The ecological activities of bacteria and phytoplankton are critical to biogeochemical cycles, yet we lack a fundamental understanding of the physical behaviors that underpin the interactions between these two groups. The focus of this project will be on the physical interactions between two model organisms, the bacterium Marinobacter adherens and the diatom

–  –  –

SAT-116

SECOND GENERATION ANTIPSYCHOTIC ASENAPINE AS A POTENTIAL ADJUVANT TO CIPROFLOXACIN

THROUGH BINDING OF EFFLUX PUMP NORA IN STAPHYLOCOCCUS AUREUS

Stephan Kudlacek, Luis Mota-Bravo.

Biological Sciences, University of California, Irvine, Irvine, CA.

Knowledge of efflux-pump inhibition in Staphylococcus aureus by the antipsychotic drug chlorpromazine has led to testing of efflux-pump inhibition with the recently FDA approved second-generation antipsychotic asenapine (ASEN). The objective of this study is to determine the capability and potential mechanism of ASEN inhibition of NorA efflux pump activity in S. aureus. We determined the following: synergistic growth-inhibitory activity was seen with a treatment of ASEN at 50 ug/mL and 1 ug/mL of ciprofloxacin (CIP); ethidium bromide (EtBr) efflux inhibition was observed with the addition of ASEN at 50 and 100 ug/mL; growth suppression was observed with treatment of ASEN at 50 ug/mL and 2ug/mL of CIP, which led to a bacteriostatic effect after 24 hours; ASEN at 50 - 200 ug/mL with or without CIP at 2 ug/mL did not cause membrane potential perturbation; and in silico docking study revealed an ASEN binding site in a predicted NorA model. In conclusion, we propose that ASEN binds to NorA to exert synergistic effects with CIP and EtBr. This warrants further investigation of ASEN as a potential adjuvant with CIP in the management of staphylococcal infections. (Supported by NIH-MBRS-IMSD Grant GM-55246 and Minority Access to Research Careers (MARC) Program, NIH Grant GM-69337.) FRI-118

DISSECTING THE PROTEIN FEATURES THAT CONTROL SUBSTRATE SPECIFICITY OF AAA+ PROTEASES

Tania Gonzalez-Robles, Izarys Rivera-Rivera, Amaris Torres-Delgado, Tania A. Baker.

Massachusetts Institute of Technology, Cambridge, Cambridge, MA.

AAA+ proteases are critical in all cells as they are involved in protein quality control and in regulatory circuits. They are composed of a compartmental peptidase (e.g., ClpP14) with active sites sequestered in an interior chamber, and a hexameric ring of an AAA+ unfoldase. E. coli ClpX and ClpA are two of the best characterized AAA+ unfoldases;

these enzymes contain one or two AAA+ rings, respectively, and each has a unique N-domain that is important for substrate recognition and adaptor protein interaction. ClpS, an adaptor protein that binds the ClpA N-domain, enhances N-end rule substrate recognition and simultaneously inhibits ssrA-tagged substrate degradation. To dissect mechanisms responsible for substrate specificity, we engineered a chimeric AAA+ protease that consists of the ClpA N-domain and the AAA+ ring of ClpX (ClpANX). This chimera carries the major determinants needed for the enzyme to bind the ClpA adaptor ClpS fused to the protein-unfolding/ATPase domain of the ClpX enzyme. With this chimera, we intend to answer whether the adaptor-binding domain of ClpA is sufficient to communicate information about substrate specificity and catalytic activity to the unrelated partner enzyme ClpX. ATP hydrolysis experiments with ClpANX will show if the N-domain of ClpA affects the ATPase rate of the ClpX AAA+ ring. Fluorescent anisotropy with labeled peptide or protein substrates will allow investigation of substrate-binding affinity and specificity. Lastly, degradation experiments with differently controlled classes of substrates (e.g., N-end rule and ssrA substrates) will reveal the degree to which the N-domain rules substrate choice and delivery.

29 UNDERGRADUATE POSTER ABSTRACTS

SAT-113

DETERMINATION OF OXIDATION SUSCEPTIBLE CYSTEINES WITHIN MAIZE PHOSPHOENOLPYRUVATE

CARBOXYLASE

Fernando Vargas, Gregory Kanzaki, Scott Grover, Jamil Momand.

California State University, Los Angeles, Los Angeles, CA.

Phosphoenolpyruvate carboxylase (PEPC) is an enzyme that is critical for the fixation of carbon dioxide within C4 plants. Evidence from thiol-reactive inhibitors suggests that PEPC is regulated by reversible oxidation of the cysteine thiols. The Km of the enzyme increases 2-3 fold when treated with a thiol-reactive agent. It is not known which cysteines are responsible for altering PEPC activity. The cysteine oxidation prediction algorithm (COPA) was used to predict the PEPC cysteines that are susceptible to redox-mediated regulation. COPA predicted three sites of oxidation in PEPC (C308, C335, and C424). The goal of our experiment is to map the redox-regulated cysteines within PEPC to give us insight into mechanisms of regulation. Methoxypolyethylene glycol-maleimide (MAL-PEG), a 5000 dal thiol-reactive agent, allowed us to determine the number of cysteines per PEPC that are exposed to oxidant. Mutant forms of PEPC, where cysteines are replaced with serines, were used to map sites that are MAL-PEG reactive. Such cysteines would be predicted to be sensitive to oxidants and downregulate PEPC activity. By exposing the enzyme with a thiol-reactive agent and systematically mutating cysteines into serines, we will gain the ability to predict both the amount and site of redox-regulated cysteines within PEPC. Redox regulation at cysteine residues is a novel way to regulate PEPC. Our research will give us insight into this regulatory mechanism.

SAT-115

STRUCTURAL AND BIOCHEMICAL CHARACTERIZATION OF A UNIQUE SHELL PROTEIN FROM GLYCYL

RADICAL ENZYME BACTERIAL MICROCOMPARTMENTS

Hoda Ahmed, Michael Thompson, Krystal McCarty, Todd Yeates.

University of California, Los Angeles, Los Angeles, CA.

Bacterial microcompartments (MCPs) are giant protein complexes that range from 80 to 150 nm in diameter. A thin protein shell surrounds their inner contents similar to a viral capsid. Shell protein monomers of the BMC type oligomerize to form hexamers which typically bear a narrow central pore. Hexamers align tightly together forming flat surfaces that make the flat facets of the polyhedral shell. MCPs encapsulate enzymes and cofactors that are involved in specific metabolic processes. Throughout the years, MCPs have been associated with various metabolic functions.



Pages:     | 1 |   ...   | 4 | 5 || 7 | 8 |   ...   | 112 |


Similar works:

«Information bulletin on July 6, 2007 ship demolition #9 from March 16 to June 28, 2007 Ship-Breaking.com Escaped from breaking Tahoma Reefer. The Estonian reefer immobilized since August 2006 after a fire in Monrovia had been sold for demolition in September 2006 to India for $283/ton. Anchored outside of the port, at the request of the local port authorities, she has been resold in March 2007 to a Bulgarian owner but then was stolen by pirates in mid-May. Her fate today is unknown. (see the...»

«Amended Newsletter 29 “This Gospel of the Kingdom will be preached to all the world as a witness to all nations, and then the end will come.” Alpha and Omega Christian Foundation, Telephone: 0416 295 270; E-mail: aocf at optusnet.com.au; www.thechristianherald.info Newsletter 29 (07/2015) 1 Friends And Leaders Around the World, Greetings Again A year ago we informed you that we were curtailing the publication of Newsletters and concentrate on The Christian Herald magazines only. We took...»

«UNIVERSIDADE CATÓLICA DE ANGOLA CENTRO DE ESTUDOS E INVESTIGAÇÃO CIENTÍFICA REVISTA ACADÉMICA LUCERE OUTUBRO DE 2012 UNIVERSIDADE CATÓLICA DE ANGOLA REVISTA ACADÉMICA LUCERE Índice APRESENTAÇÃO IDENTIDADE E PERFIL DO INSTITUTO SUPERIOR CATÓLICO DE BENGUELA 3. Universidade Católica: natureza e missão A) Natureza Renewable Energy in Angola: A New Paradigm Economic and Sectoral Context Meeting the Challenge of an Energy Crisis Taking Advantage of Solar Resources Attracting Private...»

«ALSTONFINANCE.COM Finance ADVISORY n SEPTEMBER 18, 2014 New Securitization Rules for Third-Party Due Diligence Reports Adopted Introduction and Executive Summary On August 27, 2014, the U.S. Securities and Exchange Commission (SEC) adopted a number of highly anticipated rules related to securitization and nationally recognized statistical rating organizations (NRSROs). The SEC board approved the rules and issued a release (the “NRSRO Release”).1 The rules regarding third-party due diligence...»

«NEW STINGER SYSTEM 1 INTRODUCTION | Alstom Transport SUMMARY 1. INTRODUCTION 2. APPLICATION PURPOSE 3. PRODUCT DESCRIPTION 3.1. INSULATED CONDUCTOR RAIL SYSTEM FOR ENERGY SUPPLY 3.1.1. SUPPORT HANGERS 3.1.2. CONTACT RAILS 3.1.3. RIGID JOINT CLAMPS 3.1.4. FEEDER CLAMPS 3.1.5. FIXED POINT HANGERS 3.1.6. END CAP 3.2. CURRENT COLLECTORS 3.3. TROLLEY ON STEEL TRACK RAIL 3.4. ELECTRICAL AND CONTROL PANEL WITH CABLES 3.5. SOCKET FOR POWER TRANSMISSION TO THE VEHICLE AND RAPID SECURE LINK (ON DEMAND)....»

«DEPARTMENT OF THE TREASURY Office of the Comptroller of the Currency [Docket ID OCC-2013-0005] Proposed Guidance on Deposit Advance Products; Withdrawal of Proposed Guidance on Deposit-Related Consumer Credit Products AGENCIES: Office of the Comptroller of the Currency, Treasury (OCC). ACTION: Proposed guidance with request for comment; withdrawal of proposed Guidance on Deposit-Related Consumer Credit Products. SUMMARY: The OCC is proposing guidance on safe and sound banking practices and...»

«TARİHİ KENTLER BİRLİĞİ HATAY VE ÇEVRESİ BÖLGE TOPLANTISI 18-19 NİSAN 2015 15.YILINDA TKB Yerel yönetimlerin doğa ve kültür öncelikli koruma çalışmalarında denedikleri yöntemler ve ulaşılan sonuçlar. Fevziye KÖKDİL Başkan Danışmanı Mimar GEÇMİŞİ KORUYOR GELECEĞE TAŞIYORUZ TARSUS, Türkiye’mizin güneyinde Adana ile Mersin arasında neredeyse insanlık tarihi ile yaşıt dünyanın en eski yerleşim yerlerinden birisidir. Geçmişi 10.000 yıl öncesine...»

«Lauren N. Thomas Innovative Oil Spill Remediation Spring 2012 Understanding the connection between the Alternative Response Tool Evaluation System and adoption of innovative oil spill remediation efforts Lauren Thomas ABSTRACT The National Oceanic and Atmospheric Administration developed the Alternative Response Tool Evaluation System (ARTES) as a tool to evaluate non-conventional oil spill response technologies. During the 2010 Deepwater Horizon oil spill in the Gulf of Mexico, ARTES was...»

«1 MEDIA EDUCATION FOUNDATION 60 Masonic St. Northampton, MA 01060 | TEL 800.897.0089 | info@mediaed.org | www.mediaed.org Generation M Misogyny in Media & Culture Transcript MALE STUDENT 1: Hey, what are you working on, man? MALE STUDENT 2: I got to write this paper for this one class I’m taking. I’m writing about sexism. MALE STUDENT 1: Dude, that sucks, man. Why are you taking a women’s studies class? I. INTRODUCTION TOM KEITH: You know, I’ve been asked by some people, including...»

«EARCH F ES RVER R OU NDATI ORF OCCASIONAL PAPER #56 E BS O N O JANUARY 2015 The Changing Global Trade Regime and Emergence of Mega FTAs: Strategy for India's External Sector Sustainability Geethanjali Nataraj Abhirup Bhunia Garima Sahdev OBSERVER RESEARCH FOUNDATION The Changing Global Trade Regime and Emergence of Mega FTAs: Strategy for India's External Sector Sustainability Geethanjali Nataraj Abhirup Bhunia Garima Sahdev OBSERVER RESEARCH FOUNDATION About the Authors Geethanjali Nataraj is...»

«Maejo Int. J. Sci. Technol. 2012, 6(03), 397-414 Maejo International Journal of Science and Technology ISSN 1905-7873 Available online at www.mijst.mju.ac.th Report Optimising steel hub location in Thailand Sakaradhorn Boontaveeyuwat* and Cherdvong Saengsupavanich International Maritime College, Kasetsart University, 199 Moo 6 Sukhumvit Rd., Tungsukla, Si Racha Chonburi, 20230, Thailand * Corresponding author, e-mail: sakaradhorn@gmail.com, imcskb@src.ku.ac.th Received: 6 October 2011 /...»

«Red de Información Jurídica LEGISLACION ANDINA Bolivia Derecho Procesal Civil CODIGO DE PROCEDIMIENTO CIVIL LIBRO PRIMERO DEL PROCESO EN GENERAL TITULO I DEL ORGANO JUDICIAL CAPITULO I DEL JUEZ Art. 1.(POTESTAD JUDICIAL) I. Los jueces y tribunales de justicia sustanciarán y resolverán, de acuerdo a las leyes de la República, las demandas sometidas a su jurisdicción. II. No podrán excusarse de fallas bajo pretexto de falta, oscuridad o insuficiencia de la ley, en las causas sometidas a su...»





 
<<  HOME   |    CONTACTS
2016 www.dissertation.xlibx.info - Dissertations, online materials

Materials of this site are available for review, all rights belong to their respective owners.
If you do not agree with the fact that your material is placed on this site, please, email us, we will within 1-2 business days delete him.