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2011

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Articles 151 - 180 of 466

Full-Text Articles in Biochemistry, Biophysics, and Structural Biology

Caspase-1 Dependent Il-1Β Secretion Is Critical For Host Defense In A Mouse Model Of Chlamydia Pneumoniae Lung Infection, Kenichi Shimada, Timothy R. Crother, Justin Karlin, Shuang Chen, Norika Chiba, V. Krishnan Ramanujan, Laurent Vergnes, David M. Ojcius, Moshe Arditi Jun 2011

Caspase-1 Dependent Il-1Β Secretion Is Critical For Host Defense In A Mouse Model Of Chlamydia Pneumoniae Lung Infection, Kenichi Shimada, Timothy R. Crother, Justin Karlin, Shuang Chen, Norika Chiba, V. Krishnan Ramanujan, Laurent Vergnes, David M. Ojcius, Moshe Arditi

All Dugoni School of Dentistry Faculty Articles

Chlamydia pneumoniae (CP) is an important human pathogen that causes atypical pneumonia and is associated with various chronic inflammatory disorders. Caspase-1 is a key component of the ‘inflammasome’, and is required to cleave pro-IL-1β to bioactive IL-1β. Here we demonstrate for the first time a critical requirement for IL-1β in response to CP infection. Caspase-1−/− mice exhibit delayed cytokine production, defective clearance of pulmonary bacteria and higher mortality in response to CP infection. Alveolar macrophages harbored increased bacterial numbers due to reduced iNOS levels in Caspase-1−/− mice. Pharmacological blockade of the IL-1 receptor in CP infected wild-type mice …


What Is New For An Old Molecule? Systematic Review And Recommendations On The Use Of Resveratrol, Ole Vang, Nihal Ahmad, Karen Brown, Anna Csiszar, Thomas Szekeres, Thomas Walle, Joseph M. Wu Jun 2011

What Is New For An Old Molecule? Systematic Review And Recommendations On The Use Of Resveratrol, Ole Vang, Nihal Ahmad, Karen Brown, Anna Csiszar, Thomas Szekeres, Thomas Walle, Joseph M. Wu

NYMC Faculty Publications

BACKGROUND: Resveratrol is a natural compound suggested to have beneficial health effects. However, people are consuming resveratrol for this reason without having the adequate scientific evidence for its effects in humans. Therefore, scientific valid recommendations concerning the human intake of resveratrol based on available published scientific data are necessary. Such recommendations were formulated after the Resveratrol 2010 conference, held in September 2010 in Helsingør, Denmark.

METHODOLOGY: Literature search in databases as PUBMED and ISI Web of Science in combination with manual search was used to answer the following five questions: (1)Can resveratrol be recommended in the prevention or treatment of …


Sonic Hedgehog Dependent Phosphorylation By Ck1Α And Grk2 Is Required For Ciliary Accumulation And Activation Of Smoothened, Yongbin Chen, Noriaki Sasai, Guoqiang Ma, Tao Yue, Jianhang Jia, James Briscoe, Jin Jiang Jun 2011

Sonic Hedgehog Dependent Phosphorylation By Ck1Α And Grk2 Is Required For Ciliary Accumulation And Activation Of Smoothened, Yongbin Chen, Noriaki Sasai, Guoqiang Ma, Tao Yue, Jianhang Jia, James Briscoe, Jin Jiang

Markey Cancer Center Faculty Publications

Hedgehog (Hh) signaling regulates embryonic development and adult tissue homeostasis through the GPCR-like protein Smoothened (Smo), but how vertebrate Smo is activated remains poorly understood. In Drosophila, Hh dependent phosphorylation activates Smo. Whether this is also the case in vertebrates is unclear, owing to the marked sequence divergence between vertebrate and Drosophila Smo (dSmo) and the involvement of primary cilia in vertebrate Hh signaling. Here we demonstrate that mammalian Smo (mSmo) is activated through multi-site phosphorylation of its carboxyl-terminal tail by CK1α and GRK2. Phosphorylation of mSmo induces its active conformation and simultaneously promotes its ciliary accumulation. We demonstrate that …


Investigating A Model Reversed-Phase Liquid Chromatography Stationary Phase With Vibrationally Resonant Sum Frequency Generation Spectroscopy, Arthur D. Quast Jun 2011

Investigating A Model Reversed-Phase Liquid Chromatography Stationary Phase With Vibrationally Resonant Sum Frequency Generation Spectroscopy, Arthur D. Quast

Theses and Dissertations

Reversed-phase liquid chromatography (RPLC) is a widely used technique for analytical separations but routinely requires empirical optimization. Gaining a better understanding of the molecular reasons for retention may mean more efficient separations with fewer trial and error runs to obtain optimized separations. Vibrationally resonant sum frequency generation (VR-SFG) is a surface specific technique that has allowed for in situ examination of model RPLC stationary phases under various solvent and pressure conditions. In order to improve on past work with model RPLC stationary phases two challenges had to be overcome. First, improved vibrational mode assignments of the C18 stationary phase were …


Direct Imaging Of Two-State Dynamics On The Amorphous Silicon Surface, S. Ashtekar, Gregory E. Scott, J. Lyding, M. Gruebele Jun 2011

Direct Imaging Of Two-State Dynamics On The Amorphous Silicon Surface, S. Ashtekar, Gregory E. Scott, J. Lyding, M. Gruebele

Chemistry and Biochemistry

Amorphous silicon is an important material, amidst a debate whether or not it is a glass. We produce amorphous Si surfaces by ion bombardment and vapor growth, and image discrete Si clusters which hop by two-state dynamics at 295 K. Independent of surface preparation, these clusters have an average diameter of ~5 atoms. Given prior results for metallic glasses, we suggest that this cluster size is a universal feature. The hopping activation free energy of 0.93 ± 0.15 eV is rather small, in agreement with a previously untested surface glass model. Hydrogenation quenches the two-state dynamics, apparently by increasing surface …


Progress Toward Theonellamide F, Jennifer Dawn Bettale Jun 2011

Progress Toward Theonellamide F, Jennifer Dawn Bettale

Theses and Dissertations

Theonellamide is a bicyclic peptide isolated from a marine sponge, which shows interesting biological activity. It contains several unnatural amino acids, among which are (2S,3R)-3-hydroxyasparagine (L-erythro-β-hydroxyasparagine) (β-OHAsn) and τ-L-histindino-D-alanine (τ-HAL). Although there were previous synthetic efforts toward each of these unnatural amino acids, the efforts were not ideal due to expensive starting material, time-consuming steps, and poor regioselectivity. The presented work demonstrates an inexpensive, enantioselective synthesis of β-OHAsn, which can be completed in a matter of weeks, as well as several attempts at a novel regiospecific approach toward τ-HAL, including work on a model study.


Sweet Sorghum As An Alternative Cellulosic Biofuel In Eastern Kentucky, Sarah A. Hazenfield Jun 2011

Sweet Sorghum As An Alternative Cellulosic Biofuel In Eastern Kentucky, Sarah A. Hazenfield

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Sarah A. Hazenfield in June of 2011.


Lipid Peroxidation And Neurodegenerative Disease, Tanea Reed Jun 2011

Lipid Peroxidation And Neurodegenerative Disease, Tanea Reed

Chemistry Faculty and Staff Scholarship

Lipid peroxidation is a complex process involving the interaction of oxygen-derived free radicals with polyunsaturated fatty acids, resulting in a variety of highly reactive electrophilic aldehydes. Since 1975, lipid peroxidation has been extensively studied in a variety of organisms. As neurodegenerative diseases became better understood, research establishing a link between this form of oxidative damage, neurodegeneration, and disease has provided a wealth of knowledge to the scientific community. With the advent of proteomics in 1995, the identification of biomarkers for neurodegenerative disorders became of paramount importance to better understand disease pathogenesis and develop potential therapeutic strategies. This review focuses on …


Effects Of Canola And Corn Oil Mimetic On Jurkat Cells, Gabriela Ion, Kayla Fazio, Juliana A. Akinsete, W. Elaine Hardman Jun 2011

Effects Of Canola And Corn Oil Mimetic On Jurkat Cells, Gabriela Ion, Kayla Fazio, Juliana A. Akinsete, W. Elaine Hardman

Biochemistry and Microbiology

BACKGROUND: The Western diet is high in omega-6 fatty acids and low in omega-3 fatty acids. Canola oil contains a healthier omega 3 to omega 6 ratio than corn oil. Jurkat T leukemia cells were treated with free fatty acids mixtures in ratios mimicking that found in commercially available canola oil (7% α-linolenic, 30% linoleic, 54% oleic) or corn oil (59% linoleic, 24% oleic) to determine the cell survival or cell death and changes in expression levels of inflammatory cytokines and receptors following oil treatment.

METHODS: Fatty acid uptake was assessed by gas chromatography. Cell survival and cell death were …


Determining A Method For Rendering Low Cost Cdse(Zns) Core(Shell) Quantum Dots Aqueous Soluble Via Amphiphilic Polymer Wrapping, Patrick Mcbride Jun 2011

Determining A Method For Rendering Low Cost Cdse(Zns) Core(Shell) Quantum Dots Aqueous Soluble Via Amphiphilic Polymer Wrapping, Patrick Mcbride

Materials Engineering

Herein is described the procedure of two amphiphilic polymer wrapping techniques that may be employed for obtaining aqueous soluble quantum dots (QDs) for use in biological fluorescent imaging applications. The advent of QDs has led to new nanoscale fluorescent materials that exhibit unparalleled quantum yields (QYs), high resistance to photobleaching, tunable emissions, and
absorption over a large optical range. However, the QD synthesis employed here at Cal Poly to obtain bright, photostable CdSe(ZnS) core(shell) QDs involves the use of organic solvents and surfactants, leading to hydrophobic QDs. Since all of biology relies on aqueous solubility, this hydrophobicity creates a major …


Applications Of Argentation Solid Phase Extraction To The Capsaicinoids: Purification Of Commercial Standards And Isolation Of Homodihydrocapsaicin (8-Methyl) From 'Bhut Jolokia', Robert Q. Thompson, Kathleen Loa Jun 2011

Applications Of Argentation Solid Phase Extraction To The Capsaicinoids: Purification Of Commercial Standards And Isolation Of Homodihydrocapsaicin (8-Methyl) From 'Bhut Jolokia', Robert Q. Thompson, Kathleen Loa

Faculty & Staff Scholarship

Argentation solid phase extraction was employed to purify commercial standards of capsaicin (6-ene-8-methyl) and dihydrocapsaicin (8-methyl). The purity was improved from 96.7% to 99.6% and from 89% to 96%, respectively, with 75% and 60% yield, respectively. Reversed phase solid phase extraction, argentation solid phase extraction, and preparative liquid chromatography with a C30 phase were used to isolate capsaicinoids from the fruits of 'Bhut Jolokia' peppers. The compounds capsaicin (6-ene-8-methyl) and dihydrocapsaicin (8-methyl) comprised 74% and 21% of the total mass of capsaicinoids. respectively. The remaining 5% of the capsaicinoids mass included the compounds: nordihydrocapsaicin (7-methyl), N-vanillylnonanamide, two homocapsaicin isomers, N …


Sphingolipids Containing Very-Long-Chain Fatty Acids Define A Secretory Pathway For Specific Polar Plasma Membrane Protein Targeting In Arabidopsis, Jennifer E. Markham, Diana Molino, Lionel Gissot, Yannick Bellec, Kian Hématy, Jessica Marion, Katia Belcram, Jean-Christophe Palauqui, Béatrice Satiat-Jeunemaître, Jean-Denis Faure Jun 2011

Sphingolipids Containing Very-Long-Chain Fatty Acids Define A Secretory Pathway For Specific Polar Plasma Membrane Protein Targeting In Arabidopsis, Jennifer E. Markham, Diana Molino, Lionel Gissot, Yannick Bellec, Kian Hématy, Jessica Marion, Katia Belcram, Jean-Christophe Palauqui, Béatrice Satiat-Jeunemaître, Jean-Denis Faure

Department of Biochemistry: Faculty Publications

Sphingolipids are a class of structural membrane lipids involved in membrane trafficking and cell polarity. Functional analysis of the ceramide synthase family in Arabidopsis thaliana demonstrates the existence of two activities selective for the length of the acyl chains. Very-long-acyl-chain (C > 18 carbons) but not long-chain sphingolipids are essential for plant development. Reduction of very-long-chain fatty acid sphingolipid levels leads in particular to auxin-dependent inhibition of lateral root emergence that is associated with selective aggregation of the plasma membrane auxin carriers AUX1 and PIN1 in the cytosol. Defective targeting of polar auxin carriers is characterized by specific aggregation of Rab-A2a– …


The Role Of Protein Kinase C Epsilon In Hydrogen Peroxide And Nitric Oxide Release During Oxidative Stress Caused By Extracorporeal Shockwave Lithotripsy, Edward S. Iames Jun 2011

The Role Of Protein Kinase C Epsilon In Hydrogen Peroxide And Nitric Oxide Release During Oxidative Stress Caused By Extracorporeal Shockwave Lithotripsy, Edward S. Iames

PCOM Biomedical Studies Student Scholarship

Clinical extracorporeal shock wave lithotripsy (ESWL) treatment to ablate kidney stones can cause acute damage to the renal microvasculature. Accumulation of continued treatment with shockwave therapy can lead to chronic damage to the kidney, and lead to clinical hypertension. Shockwaves have been shown to stimulate endothelial cells to release superoxide (SO), which is converted to hydrogen peroxide (H2O2), and reacts with nitric oxide (NO) to produce peroxynitrite anion (OONO-), creating a powerful oxidant that increases oxidative stress while simultaneously reducing NO bioavailability. Increased oxidative stress during events such as ESWL, also uncouples NO production …


Immune Evasion Of Porcine Reproductive And Respiratory Syndrome Virus Through Glycan Shielding Involves Both Glycoprotein 5 As Well As Glycoprotein 3, Hiep Vu, Byungjoon Kwon, Kyoung-Jin Yoon, William W. Laegreid, Asit K. Pattnaik, Fernando A. Osorio Jun 2011

Immune Evasion Of Porcine Reproductive And Respiratory Syndrome Virus Through Glycan Shielding Involves Both Glycoprotein 5 As Well As Glycoprotein 3, Hiep Vu, Byungjoon Kwon, Kyoung-Jin Yoon, William W. Laegreid, Asit K. Pattnaik, Fernando A. Osorio

School of Veterinary and Biomedical Sciences: Faculty Publications

Passive administration of porcine reproductive and respiratory syndrome virus (PRRSV) neutralizing antibodies (NAbs) can effectively protect pigs against PRRSV infection. However, after PRRSV infection, pigs typically develop a weak and deferred NAb response. One major reason for such a meager NAb response is the phenomenon of glycan shielding involving GP5, a major glycoprotein carrying one major neutralizing epitope. We describe here a type II PRRSV field isolate (PRRSV-01) that is highly susceptible to neutralization and induces an atypically rapid, robust NAb response in vivo. Sequence analysis shows that PRRSV-01 lacks two N-glycosylation sites, normally present in wild-type (wt) PRRSV strains, …


Tension Directly Stabilizes Reconstituted Kinetochore-Microtubule Attachments, Bungo Akiyoshi, Krishna K. Sarangapani, Andrew F. Powers, Christian R. Nelson, Steve Reichow, Hugo Arellano-Santoyo, Tamir Gonen, Jeffrey A. Ranish, Charles L. Asbury, Sue Biggins Jun 2011

Tension Directly Stabilizes Reconstituted Kinetochore-Microtubule Attachments, Bungo Akiyoshi, Krishna K. Sarangapani, Andrew F. Powers, Christian R. Nelson, Steve Reichow, Hugo Arellano-Santoyo, Tamir Gonen, Jeffrey A. Ranish, Charles L. Asbury, Sue Biggins

Chemistry Faculty Publications and Presentations

Kinetochores are macromolecular machines that couple chromosomes to dynamic microtubule tips during cell division, thereby generating force to segregate the chromosomes. Accurate segregation depends on selective stabilization of correct ‘bi-oriented’ kinetochore-microtubule attachments, which come under tension due to opposing forces exerted by microtubules. Tension is thought to stabilize these bi-oriented attachments indirectly, by suppressing the destabilizing activity of a kinase, Aurora B. However, a complete mechanistic understanding of the role of tension requires reconstitution of kinetochore-microtubule attachments for biochemical and biophysical analyses in vitro. Here we show that native kinetochore particles retaining the majority of kinetochore proteins can be …


Oxidation Kinetics Of Silver Thin Films For Antimicrobial Applications In The Health Care Industry, Sean D. Morham Jun 2011

Oxidation Kinetics Of Silver Thin Films For Antimicrobial Applications In The Health Care Industry, Sean D. Morham

Materials Engineering

To determine if varying city water qualities from around the United States can support a developing “oxidation corrosion of silver thin films” method of creating aqueous ionic silver solutions for the anti-microbial treatment of healthcare linens, a test was devised holding all variables constant with the exception of water quality parameters. This corrosion style test was done in order to assess a pass/fail criteria of 25 ppb ionic silver concentration in the aqueous solutions which resulted from the corrosion of silver thin film coated substrates. Above 25 ppb being a pass, below 25 ppb being a fail. While varying the …


Examination Of Nak-Associated Protein-1 (Nap1) Homo And Hetero-Interactions In The Interferon Pathway”, Richard Call May 2011

Examination Of Nak-Associated Protein-1 (Nap1) Homo And Hetero-Interactions In The Interferon Pathway”, Richard Call

Theses and Dissertations

Double stranded RNA (dsRNA), the genomic material of some viruses and a replication intermediate in others, is recognized by multiple signaling receptors that initiate the anti-viral response1. Viruses have developed mechanisms to circumvent the anti-viral response by targeting components of the signaling pathway. An example of one such pathway is the TLR3 signaling pathway, which contains a kinase complex that activates interferon regulatory factor 3 (IRF3), leading to production of type I interferons. The kinase complex consists of a scaffold protein, NAK-associated protein 1 (NAP1), and two kinases, TANK-binding kinase 1 (TBK-1) and IκB kinase epsilon (IKKε). A fourty residue …


Hivtoolbox, An Integrated Web Application For Investigating Hiv, David P. Sargeant, Sandeep Deverasetty, Yang Luo, Angel Villahoz Baleta, Stephanie Zobrist, Viraj Rathnayake, Jacqueline C. Russo, Jay Vyas, Mark A. Muesing, Martin Schiller May 2011

Hivtoolbox, An Integrated Web Application For Investigating Hiv, David P. Sargeant, Sandeep Deverasetty, Yang Luo, Angel Villahoz Baleta, Stephanie Zobrist, Viraj Rathnayake, Jacqueline C. Russo, Jay Vyas, Mark A. Muesing, Martin Schiller

Life Sciences Faculty Research

Many bioinformatic databases and applications focus on a limited domain of knowledge federating links to information in other databases. This segregated data structure likely limits our ability to investigate and understand complex biological systems. To facilitate research, therefore, we have built HIVToolbox, which integrates much of the knowledge about HIV proteins and allows virologists and structural biologists to access sequence, structure, and functional relationships in an intuitive web application. HIV-1 integrase protein was used as a case study to show the utility of this application. We show how data integration facilitates identification of new questions and hypotheses much more rapid …


The Exonuclease Activity Of Hpmc2 Is Required For Transcriptional Regulation Of The Qr Gene And Repair Of Estrogen-Induced Abasic Sites, N. Krishnamurthy, C. R. Ngam, Anthony J. Berdis, M. M. Montano May 2011

The Exonuclease Activity Of Hpmc2 Is Required For Transcriptional Regulation Of The Qr Gene And Repair Of Estrogen-Induced Abasic Sites, N. Krishnamurthy, C. R. Ngam, Anthony J. Berdis, M. M. Montano

Chemistry Faculty Publications

We have previously reported that the expression of antioxidative stress enzymes is upregulated by trans-hydroxytamoxifen (TOT) in breast epithelial cell lines providing protection against estrogen-induced DNA damage. This regulation involves Estrogen Receptor β (ERβ) recruitment to the Electrophile Response Element (EpRE) and a novel protein, human homolog of Xenopus gene which Prevents Mitotic Catastrophe (hPMC2). We have also demonstrated that ERβ and hPMC2 are required for TOT-dependent recruitment of poly (ADP-ribose) polymerase 1 (PARP-1) and Topoisomerase IIβ (Topo IIβ) to the EpRE. Sequence analysis reveals that the C-terminus of hPMC2 encodes a putative exonuclease domain. Using in vitro kinetic assays, …


Pcr Amplification Of Trypanosoma Cruzi - Specific Dna From Raccoon Blood Samples, Colin Moss May 2011

Pcr Amplification Of Trypanosoma Cruzi - Specific Dna From Raccoon Blood Samples, Colin Moss

Mahurin Honors College Capstone Experience/Thesis Projects

The parasitic protist Trypanosoma cruzi is the causative agent of Chagas Disease. Chagas Disease causes greater than 15,000 deaths each year, and nearly 28 million people are believed to be at risk of infection in Central and South America. This parasite has been described in many mammalian host species and has also been described in the United States. The purpose of this study was to attempt to use PCR to amplify T. cruzi-specific DNA directly from blood samples obtained from raccoons (Procyon lotor) trapped in Warren and Barren Counties of Kentucky in 2007 and 2008. DNA was …


Processing The Interspecies Quorum-Sensing Signal Autoinducer-2 (Ai-2) Characterization Of Phospho-(S)-4,5-Dihydroxy-2,3-Pentanedione Isomerization By Lsrg Protein, J. C. Marques, P. Lamosa, Caitlin Elizabeth Russell , '11, R. Ventura, C. D. Maycock, M. F. Semmelhack, Stephen T. Miller, K. B. Xavier May 2011

Processing The Interspecies Quorum-Sensing Signal Autoinducer-2 (Ai-2) Characterization Of Phospho-(S)-4,5-Dihydroxy-2,3-Pentanedione Isomerization By Lsrg Protein, J. C. Marques, P. Lamosa, Caitlin Elizabeth Russell , '11, R. Ventura, C. D. Maycock, M. F. Semmelhack, Stephen T. Miller, K. B. Xavier

Chemistry & Biochemistry Faculty Works

The molecule (S)-4,5-dihydroxy-2,3-pentanedione (DPD) is produced by many different species of bacteria and is the precursor of the signal molecule autoinducer-2 (AI-2). AI-2 mediates interspecies communication and facilitates regulation of bacterial behaviors such as biofilm formation and virulence. A variety of bacterial species have the ability to sequester and process the AI-2 present in their environment, thereby interfering with the cell-cell communication of other bacteria. This process involves the AI-2-regulated lsr operon, comprised of the Lsr transport system that facilitates uptake of the signal, a kinase that phosphorylates the signal to phospho-DPD (P-DPD), and enzymes (like LsrG) that are responsible …


Controlling The Activity Of A Phosphatase And Tensin Homolog (Pten) By Membrane Potential, Jérôme J. Lacroix, Christian R. Halaszovich, Daniela N. Schreiber, Michael G. Leitner, Francisco Bezanilla, Dominik Oliver, Carlos A. Villalba-Galea May 2011

Controlling The Activity Of A Phosphatase And Tensin Homolog (Pten) By Membrane Potential, Jérôme J. Lacroix, Christian R. Halaszovich, Daniela N. Schreiber, Michael G. Leitner, Francisco Bezanilla, Dominik Oliver, Carlos A. Villalba-Galea

School of Pharmacy Faculty Articles

The recently discovered voltage-sensitive phosphatases (VSPs) hydrolyze phosphoinositides upon depolarization of the membrane potential, thus representing a novel principle for the transduction of electrical activity into biochemical signals. Here, we demonstrate the possibility to confer voltage sensitivity to cytosolic enzymes. By fusing the tumor suppressor PTEN to the voltage sensor of the prototypic VSP from Ciona intestinalis, Ci-VSP, we generated chimeric proteins that are voltage-sensitive and display PTEN-like enzymatic activity in a strictly depolarization-dependent manner in vivo. Functional coupling of the exogenous enzymatic activity to the voltage sensor is mediated by a phospholipid-binding motif at the interface between voltage sensor …


The Csc Is Required For Complete Radial Spoke Assembly And Wild-Type Ciliary Motility, Erin E. Dymek, Thomas Heuser, Daniela Nicastro, Elizabeth F. Smith May 2011

The Csc Is Required For Complete Radial Spoke Assembly And Wild-Type Ciliary Motility, Erin E. Dymek, Thomas Heuser, Daniela Nicastro, Elizabeth F. Smith

Dartmouth Scholarship

The ubiquitous calcium binding protein, calmodulin (CaM), plays a major role in regulating the motility of all eukaryotic cilia and flagella. We previously identified a CaM and Spoke associated Complex (CSC) and provided evidence that this complex mediates regulatory signals between the radial spokes and dynein arms. We have now used an artificial microRNA (amiRNA) approach to reduce expression of two CSC subunits in Chlamydomonas. For all amiRNA mutants, the entire CSC is lacking or severely reduced in flagella. Structural studies of mutant axonemes revealed that assembly of radial spoke 2 is defective. Furthermore, analysis of both flagellar beating and …


Characterization Of Esterase Activity From The Bacteria, Francisella Tularensis, The Causative Agent Of Tularemia, Leigh Anna Weston May 2011

Characterization Of Esterase Activity From The Bacteria, Francisella Tularensis, The Causative Agent Of Tularemia, Leigh Anna Weston

Undergraduate Honors Thesis Collection

Francisella tularensis is the bacteria responsible for causing the disease tularemia and is listed as one of the top three-biowarfare agents. Among the proteins essential to the virulence and infectivity of F.tularensis are multiple esterases, which are enzymes that break down various ester, thioester, and amide bonds. In this project, the catalytic activity, substrate speci fi city, and structure of a putative esterase from F.tularensis was studied. Latent fluorophores based on the molecule, fluorescein, were unmasked by the enzymatic activity of the esterase and the increase in fluorescence was measured over time to determine how well the e tcrase recognized …


Chiral Recognition Study Of A Bimolecular Process In Amino Acid Chiral Ionic Liquids, Laurel Millikan Heckman May 2011

Chiral Recognition Study Of A Bimolecular Process In Amino Acid Chiral Ionic Liquids, Laurel Millikan Heckman

Undergraduate Honors Thesis Collection

In this study, chiral ionic liquid (CIL) solvents were prepared and tested for their chiral discrimination ability by probing with luminescence quenching. The CIL's were also tested for their impurities, viscosity and density. These experiments will help to determine the ability of CIL's to act as solvents in asymmetric catalysis. The chiral ionic liquids in this study were composed of amino acid methyl ester cations and bis(trifluoromethane) sulfonimide or bistri flimide anions (i.e. I-alanine methyl ester bistriflimid e, d-alanine methyl ester bistr iflim ide and I-leuci ne methyl ester bistriflimde). Circularly polarized luminescence (CPL) and its quenching in the chiral …


Digeorge Critical Region 8 (Dgcr8) Is A Double-Cysteine-Ligated Heme Protein., Ian Barr, Aaron T. Smith, Rachel Senturia, Yanqiu Chen, Brooke D. Scheidemantle, Judith N. Burstyn, Feng Guo May 2011

Digeorge Critical Region 8 (Dgcr8) Is A Double-Cysteine-Ligated Heme Protein., Ian Barr, Aaron T. Smith, Rachel Senturia, Yanqiu Chen, Brooke D. Scheidemantle, Judith N. Burstyn, Feng Guo

Natural Sciences and Mathematics | Faculty Scholarship

All known heme-thiolate proteins ligate the heme iron using one cysteine side chain. We previously found that DiGeorge Critical Region 8 (DGCR8), an essential microRNA processing factor, associates with heme of unknown redox state when overexpressed in Escherichia coli. On the basis of the similarity of the 450-nm Soret absorption peak of the DGCR8-heme complex to that of cytochrome P450 containing ferrous heme with CO bound, we identified cysteine 352 as a probable axial ligand in DGCR8. Here we further characterize the DGCR8-heme interaction using biochemical and spectroscopic methods. The DGCR8-heme complex is highly stable, with a half-life exceeding 4 …


Nogo-B Receptor Is Necessary For Cellular Dolichol Biosynthesis And Protein N-Glycosylation., Kenneth D Harrison, Eon Joo Park, Ningguo Gao, Andrew Kuo, Jeffrey S. Rush, Charles J Waechter, Mark A Lehrman, William C Sessa May 2011

Nogo-B Receptor Is Necessary For Cellular Dolichol Biosynthesis And Protein N-Glycosylation., Kenneth D Harrison, Eon Joo Park, Ningguo Gao, Andrew Kuo, Jeffrey S. Rush, Charles J Waechter, Mark A Lehrman, William C Sessa

Molecular and Cellular Biochemistry Faculty Publications

Dolichol monophosphate (Dol-P) functions as an obligate glycosyl carrier lipid in protein glycosylation reactions. Dol-P is synthesized by the successive condensation of isopentenyl diphosphate (IPP), with farnesyl diphosphate catalysed by a cis-isoprenyltransferase (cis-IPTase) activity. Despite the recognition of cis-IPTase activity 40 years ago and the molecular cloning of the human cDNA encoding the mammalian enzyme, the molecular machinery responsible for regulating this activity remains incompletely understood. Here, we identify Nogo-B receptor (NgBR) as an essential component of the Dol-P biosynthetic machinery. Loss of NgBR results in a robust deficit in cis-IPTase activity and Dol-P production, leading to diminished levels of …


Quorum Sensing In Archaea, Charles Mackin May 2011

Quorum Sensing In Archaea, Charles Mackin

Honors Scholar Theses

Bacteria coordinate cell density dependent behaviors by communicating through chemical intermediaries in a process called quorum sensing. In a bacterial culture, individual cells will constitutively produce signal molecules, termed autoinducers, and export them into the environment. When the concentration of autoinducers reaches a threshold, the cells sense that they are in a specific situation, which requires the upregulation of certain genes. This upregulation causes the bacteria to produce proteins that allow them to take part in a coordinated population-wide behavior.

In bacteria that are naturally competent, or capable of importing DNA from the environment, the expression of competence genes is …


Design And Bio-Production Of A Nanoparticle Avian Influenza Vaccine, Kashif N. Ather May 2011

Design And Bio-Production Of A Nanoparticle Avian Influenza Vaccine, Kashif N. Ather

Honors Scholar Theses

Influenza is one of the most common diseases in the world and the cause for numerous deaths every year. The primary method of combating the disease is the influenza vaccine, which is produced by inoculating chicken eggs with inactivated virus. An emerging solution is to use Self-Assembling Polypeptide Nanoparticles (SAPN) to elicit an immune response in the body, rather than using inactivated viruses. This project focuses on the synthesis, purification, and refolding of two peptide constructs, BN5C and S43, which are specific protein sequences that under the right conditions will refold into the 3-dimensional structures necessary for producing an immune …


Characterizing The Role Of The Bacterial Metallothionein, Smta, In Mammalian Infection, Stephanie R. Davis May 2011

Characterizing The Role Of The Bacterial Metallothionein, Smta, In Mammalian Infection, Stephanie R. Davis

Honors Scholar Theses

Mammalian metallothioneins (MT) are induced by various immunomodulatory molecules and are involved in a spectrum of immune processes such as essential metal homeostasis, detoxification of certain heavy metals, inflammation, and immune cell trafficking [1-3]. A bacterial metallothionein, SmtA, shares some sequence homology with mammalian MT as well as its metal-binding capabilities [4]. In addition to its ability to sequester heavy metals, eukaryotic MT has also been shown to scavenge free radicals such as reactive oxygen and nitrogen species (ROS, RNS), interfering with their toxic effects on cells and potentially influencing their regulatory roles in cell proliferation and differentiation [5, 6]. …