Normal modes of prion proteins: from native to infectious particle.


:Prion proteins (PrP) are the infectious agent in transmissible spongiform encephalopathies (i.e., mad cow disease). To be infectious, prion proteins must undergo a conformational change involving a decrease in α-helical content along with an increase in β-strand content. This conformational change was evaluated by means of elastic normal modes. Elastic normal modes show a diminution of two α-helices by one and two residues, as well as an extension of two β-strands by three residues each, which could instigate the conformational change. The conformational change occurs in a region that is compatible with immunological studies, and it is observed more frequently in mutant prions that are prone to conversion than in wild-type prions because of differences in their starting structures, which are amplified through normal modes. These findings are valuable for our comprehension of the conversion mechanism associated with the conformational change in prion proteins.






Samson AO,Levitt M




Has Abstract


2011-03-29 00:00:00












  • Internal dynamics of the tryptophan repressor (TrpR) and two functionally distinct TrpR variants, L75F-TrpR and A77V-TrpR, in their l-Trp-bound forms.

    abstract::Backbone amide dynamics of the Escherichia coli tryptophan repressor protein (WT-TrpR) and two functionally distinct variants, L75F-TrpR and A77V-TrpR, in their holo (l-tryptophan corepressor-bound) form have been characterized using (15)N nuclear magnetic resonance (NMR) relaxation. The three proteins possess very si...


    pub_type: 杂志文章


    authors: Tripet BP,Goel A,Copie V

    更新日期:2011-06-14 00:00:00

  • An Enzyme-Directed Imidazoquinoline Activated by Drug Resistance.

    abstract::Drug efflux and enzymatic drug degradation are two cellular mechanisms that contribute to drug resistance in many cancers. Herein, we report the synthesis and in vitro activity of a pro-immunostimulant that exploits both processes in tandem to selectively confer cancer-mediated immunogenicity. We demonstrate that an i...


    pub_type: 杂志文章


    authors: Burt AJ,Hantho JD,Nielsen AE,Mancini RJ

    更新日期:2018-04-17 00:00:00

  • Conservation of electrostatic properties within enzyme families and superfamilies.

    abstract::Electrostatic interactions play a key role in enzyme catalytic function. At long range, electrostatics steer the incoming ligand/substrate to the active site, and at short distances, electrostatics provide the specific local interactions for catalysis. In cases in which electrostatics determine enzyme function, orthol...


    pub_type: 杂志文章


    authors: Livesay DR,Jambeck P,Rojnuckarin A,Subramaniam S

    更新日期:2003-04-01 00:00:00

  • Multiple replacements of glutamine 143 in human manganese superoxide dismutase: effects on structure, stability, and catalysis.

    abstract::Glutamine 143 in human manganese superoxide dismutase (MnSOD) forms a hydrogen bond with the manganese-bound solvent molecule and is investigated by replacement using site-specific mutagenesis. Crystal structures showed that the replacement of Gln 143 with Ala made no significant change in the overall structure of the...


    pub_type: 杂志文章


    authors: Lévêque VJ,Stroupe ME,Lepock JR,Cabelli DE,Tainer JA,Nick HS,Silverman DN

    更新日期:2000-06-20 00:00:00

  • Overexpression and divalent metal binding properties of the methionyl aminopeptidase from Pyrococcus furiosus.

    abstract::The gene encoding for the methionyl aminopeptidase from the hyperthermophilic archaeon Pyrococcus furiosus (PfMetAP-II; EC has been inserted into a pET 27b(+) vector and overexpressed in Escherichia coli. The new expression system resulted in a 5-fold increase in purified enzyme obtained from a 5 L fermento...


    pub_type: 杂志文章


    authors: Meng L,Ruebush S,D'souza VM,Copik AJ,Tsunasawa S,Holz RC

    更新日期:2002-06-11 00:00:00

  • The activities of recombinant gamma-carboxyglutamic-acid-deficient mutants of activated human protein C toward human coagulation factor Va and factor VIII in purified systems and in plasma.

    abstract::The dependence of the activity of recombinant activated human protein C (r-APC) on each of its nine gamma-carboxyglutamic (Gla) residues (sequence positions 6, 7, 14, 16, 19, 20, 25, 26, and 29) has been assessed in purified systems and in plasma using r-mutants in which each Gla residue of r-APC was individually alte...


    pub_type: 杂志文章


    authors: Jhingan A,Zhang L,Christiansen WT,Castellino FJ

    更新日期:1994-02-22 00:00:00

  • Hydrogen exchange of individual amide protons in the F helix of cyanometmyoglobin.

    abstract::Hydrogen exchange of the individual amide protons of alanine-90 (F5), glutamine-91 (F6), serine-92 (F7), and histidine-93 (F8) residues in cyanometmyoglobin of sperm whale has been studied by 1H nuclear magnetic resonance spectroscopy at 360 MHz. The amide proton resonance of F5, F6, and F7 have been assigned by use o...


    pub_type: 杂志文章


    authors: Kumar NV,Kallenbach NR

    更新日期:1985-12-17 00:00:00

  • Slow refolding kinetics in yeast iso-2 cytochrome c.

    abstract::In refolding of iso-2 cytochrome c from Saccharomyces cerevisiae, there are two slow folding reactions, tau 1a and tau 1b. The slower of the slow reactions, tau 1a = 100-200 s, is observed only by absorbance changes, while tau 1b (10-20-fold faster) is detected by fluorescence changes. The temperature dependence of th...


    pub_type: 杂志文章


    authors: Osterhout JJ Jr,Nall BT

    更新日期:1985-12-31 00:00:00

  • Cadmium-113 nuclear magnetic resonance studies of cadmium-substituted derivatives of bovine superoxide dismutase.

    abstract::We have prepared the following cadmium-113-substituted derivatives of bovine superoxide dismutase and recorded the nuclear magnetic resonance (NMR) spectrum of the cadmium: 2Cd(II), in which Cd(II) is presumed to bind to the Zn(II) site and the copper site is unoccupied, and 2Cd(II)--2Cu(I), which is analogous to the ...


    pub_type: 杂志文章


    authors: Bailey DB,Ellis PD,Fee JA

    更新日期:1980-02-05 00:00:00

  • Electrostatic effects in myoglobin. Application of the modified Tanford-Kirkwood theory to myoglobins from horse, California grey whale, harbor seal, and California sea lion.

    abstract::The modified Tanford-Kirkwood electrostatic theory (Shire et al., 1974a) was applied to ferrimyoglobins from the following animal species: sperm whale (Physeter catodon), horse, California grey whale (Eschrichtius gibbosus), harbor seal (Phoca vitulina), and California sea lion (Zalophus californianus). Computations w...


    pub_type: 杂志文章


    authors: Shire SJ,Hanania GI,Gurd FR

    更新日期:1975-04-08 00:00:00

  • Minor influence of sialic acid on conformation of a membrane-bound oligosaccharide recognition site.

    abstract::Wideline 2H NMR spectroscopy was used to assess the conformational and orientational effects of N-acetylneuraminic acid (NeuAc) (sialic acid) as a component of a particular oligosaccharide chain at a bilayer membrane surface. For this purpose, three glycosphingolipids, sharing a neutral core tetrasaccharide and differ...


    pub_type: 杂志文章


    authors: Jones DH,Barber KR,Grant CW

    更新日期:1996-04-16 00:00:00

  • Probing Proline Residues in the Prokaryotic Ligand-Gated Ion Channel, ELIC.

    abstract::Erwinia ligand-gated ion channel (ELIC) is a bacterial homologue of vertebrate pentameric ligand-gated ion channels (pLGICs) and has proven to be a valuable model for understanding the structure and function of this important protein family. There is nevertheless still a question about whether molecular details can be...


    pub_type: 杂志文章


    authors: Mosesso R,Dougherty DA,Lummis SCR

    更新日期:2018-07-10 00:00:00

  • Effects of the N-terminal acylamido group of imidazole- and pyrrole-containing polyamides on DNA sequence specificity and binding affinity.

    abstract::The N-terminal formamido group on imidazole- and pyrrole-containing polyamides causes stacked polyamides to bind in the minor groove of DNA in the staggered motif, and it also increases the binding affinity compared to those of non-formamido compounds. To further investigate the role of the N-terminal acylamido in aff...


    pub_type: 杂志文章


    authors: Westrate L,Mackay H,Brown T,Nguyen B,Kluza J,Wilson WD,Lee M,Hartley JA

    更新日期:2009-06-23 00:00:00

  • GrpE accelerates nucleotide exchange of the molecular chaperone DnaK with an associative displacement mechanism.

    abstract::The ATP hydrolysis and protein-binding and release cycle of the molecular chaperone DnaK is regulated by the accessory proteins GrpE and DnaJ. Here we describe a study of the formation of complexes between the molecular chaperone DnaK, its nucleotide exchange factor GrpE, and the fluorescent ADP analog N8-[4-[(N'-meth...


    pub_type: 杂志文章


    authors: Packschies L,Theyssen H,Buchberger A,Bukau B,Goody RS,Reinstein J

    更新日期:1997-03-25 00:00:00

  • A structure-based approach to a synthetic vaccine for HIV-1.

    abstract::The generation of neutralizing antibodies by peptide immunization is dependent on achieving conformational compatibility between antibodies and native protein. Consequently, approaches are needed for developing conformational mimics of protein neutralization sites. We replace putative main-chain hydrogen bonds (NH -->...


    pub_type: 杂志文章


    authors: Cabezas E,Wang M,Parren PW,Stanfield RL,Satterthwait AC

    更新日期:2000-11-28 00:00:00

  • Binding of the proline-rich segment of myelin basic protein to SH3 domains: spectroscopic, microarray, and modeling studies of ligand conformation and effects of posttranslational modifications.

    abstract::Myelin basic protein (MBP) is a multifunctional protein involved in maintaining the stability and integrity of the myelin sheath by a variety of interactions with membranes and with cytoskeletal and other proteins. A central segment of MBP is highly conserved in mammals and consists of a membrane surface-associated am...


    pub_type: 杂志文章


    authors: Polverini E,Rangaraj G,Libich DS,Boggs JM,Harauz G

    更新日期:2008-01-08 00:00:00

  • Effect of cholesterol on the membrane interaction of Modelin-5 isoforms.

    abstract::Modelin-5 isoforms were used to gain an insight into the effects of amidation on antimicrobial selectivity. When tested against Escherichia coli, amidation increased toxicity 10-fold (MIC = 31.25 μM) while showing limited increased hemolytic activity (2% lysis). Our results show that both the amidated and non-amidated...


    pub_type: 杂志文章


    authors: Dennison SR,Phoenix DA

    更新日期:2011-12-20 00:00:00

  • Conformational flexibility of PEP mutase.

    abstract::Previous work has indicated that PEP mutase catalyzes the rearrangement of phosphoenolpyruvate to phosphonopyruvate by a dissociative mechanism. The crystal structure of the mutase with Mg(II) and sulfopyruvate (a phosphonopyruvate analogue) bound showed that the substrate is anchored to the active site by the Mg(II),...


    pub_type: 杂志文章


    authors: Liu S,Lu Z,Han Y,Jia Y,Howard A,Dunaway-Mariano D,Herzberg O

    更新日期:2004-04-20 00:00:00

  • Inversion of the stereochemistry around the sulfur atom of the axial methionine side chain through alteration of amino acid side chain packing in Hydrogenobacter thermophilus cytochrome C552 and its functional consequences.

    abstract::In cytochrome c, the coordination of the axial Met Sδ atom to the heme Fe atom occurs in one of two distinctly different stereochemical manners, i.e., R and S configurations, depending upon which of the two lone pairs of the Sδ atom is involved in the bond; hence, the Fe-coordinated Sδ atom becomes a chiral center. In...


    pub_type: 杂志文章


    authors: Tai H,Tonegawa K,Shibata T,Hemmi H,Kobayashi N,Yamamoto Y

    更新日期:2013-07-16 00:00:00

  • Effects of the A.T/T.A degeneracy of pyrrole--imidazole polyamide recognition in the minor groove of DNA.

    abstract::Pairing rules have been developed to predict the sequence specificity of minor groove binding polyamides containing pyrrole (Py) and imidazole (Im) amino acids. An Im/Py pair distinguishes G.C from C.G and both of these from A.T/T.A base pairs. A Py/Py pair appears not to distinguish A.T from T.A base pairs. To test t...


    pub_type: 杂志文章


    authors: White S,Baird EE,Dervan PB

    更新日期:1996-09-24 00:00:00

  • Bound Compound, Interfacial Water, and Phenyl Ring Rotation Dynamics of a Compound in the DNA Minor Groove.

    abstract::DB2277, a heterocyclic diamidine, is a successful design for mixed base pair (bp) DNA sequence recognition. The compound has a central aza-benzimidazole group that forms two H-bonds with a GC bp that has flanking AT bps. The nuclear magnetic resonance structure of the DB2277-DNA complex with an AAGATA recognition site...


    pub_type: 杂志文章


    authors: Harika NK,Wilson WD

    更新日期:2018-08-21 00:00:00

  • Cytotoxic effects of inhibitors of de novo pyrimidine biosynthesis upon Plasmodium falciparum.

    abstract::The malarial parasite Plasmodium falciparum can only synthesize pyrimidine nucleotides via the de novo pathway which is therefore a suitable target for development of antimalarial drugs. New assay procedures have been developed using high-pressure liquid chromatography (HPLC) which enable concurrent measurement of pyr...


    pub_type: 杂志文章


    authors: Seymour KK,Lyons SD,Phillips L,Rieckmann KH,Christopherson RI

    更新日期:1994-05-03 00:00:00

  • Isolation and characterization of papaya peptidase A from commercial chymopapain.

    abstract::Chromatography on a column of SP-Sephadex shows that commercial chymopapain contains three components with proteolytic activity. Each behaves as a single protein upon rechromatography and electrophoresis on polyacrylamide gels. The major component, which represents 31% of the activity applied to the column and is the ...


    pub_type: 杂志文章


    authors: Robinson GW

    更新日期:1975-08-12 00:00:00

  • Eukaryotic Catalase-Peroxidase: The Role of the Trp-Tyr-Met Adduct in Protein Stability, Substrate Accessibility, and Catalysis of Hydrogen Peroxide Dismutation.

    abstract::Recently, it was demonstrated that bifunctional catalase-peroxidases (KatGs) are found not only in archaea and bacteria but also in lower eukaryotes. Structural studies and preliminary biochemical data of the secreted KatG from the rice pathogen Magnaporthe grisea (MagKatG2) suggested both similar and novel features w...


    pub_type: 杂志文章


    authors: Gasselhuber B,Carpena X,Graf MM,Pirker KF,Nicolussi A,Sündermann A,Hofbauer S,Zamocky M,Furtmüller PG,Jakopitsch C,Oostenbrink C,Fita I,Obinger C

    更新日期:2015-09-08 00:00:00

  • Neutral and Cationic Sulfonamido Derivatives of the Fluorescent Probe 2-p-Toluidinylnaphthalene-6-sulfonate. Properties and Mechanistic implications.

    abstract::The sensitivity of the fluorescence energy of 2-p-toluidinylnaphthalene-6-sulfonate (TNS) to apparent solvent polarity is considerably greater in methanol-water mixtures and lower primary alcohols than in higher primary alcohols or solvents containing no hydroxyl groups. It is suggested that the behavior of TNS in low...


    pub_type: 杂志文章


    authors: Greene FC

    更新日期:1975-02-25 00:00:00

  • Cysteine auxotrophy of human leukemic lymphoblasts is associated with decreased amounts of intracellular cystathionase protein.

    abstract::A series of human lymphoblastoid cell lines derived from nonleukemic donors are known to be cysteine prototrophs (cys+), while several lymphoblastoid lines derived from leukemic donors are cysteine auxotrophs (cys-). We have tested representative cell lines of each type for their content of cystathionase enzyme activi...


    pub_type: 杂志文章


    authors: Glode LM,Kriegler MP,Livingston DM

    更新日期:1981-03-03 00:00:00

  • Inactivation of photoexcited rhodopsin in retinal rods: the roles of rhodopsin kinase and 48-kDa protein (arrestin).

    abstract::The inactivation of excited rhodopsin in the presence of ATP, rhodopsin kinase, and/or arrestin has been studied from its effect on the two subsequent steps in the light-induced enzymatic cascade: metarhodopsin II catalyzed activation of G-protein and G-protein-dependent activation of cGMP phosphodiesterase. The inact...


    pub_type: 杂志文章


    authors: Bennett N,Sitaramayya A

    更新日期:1988-03-08 00:00:00

  • Heterogeneous glycosylation of immunoglobulin E constructs characterized by top-down high-resolution 2-D mass spectrometry.

    abstract::Posttranslational glycosylation is critical for biological function of many proteins, but its structural characterization is complicated by natural heterogeneity, multiple glycosylation sites, and different forms. Here, a top-down mass spectrometry (MS) characterization is applied to three constructs of the Fc segment...


    pub_type: 杂志文章


    authors: Fridriksson EK,Beavil A,Holowka D,Gould HJ,Baird B,McLafferty FW

    更新日期:2000-03-28 00:00:00

  • Akt-dependent antiapoptotic action of insulin is sensitive to farnesyltransferase inhibitor.

    abstract::CHO cells expressing the human insulin receptors (IR) were used to evaluate the effect of the potent farnesyltransferase inhibitor, manumycin, on insulin antiapoptotic function. Cell treatment with manumycin blocked insulin's ability to suppress pro-apoptotic caspase-3 activity which led to time-dependent proteolytic ...


    pub_type: 杂志文章


    authors: Park D,Pandey SK,Maksimova E,Kole S,Bernier M

    更新日期:2000-10-17 00:00:00

  • DNA binding properties and replication activity of the T antigen related D2 phosphoprotein.

    abstract::According to earlier genetic experiments, a region within the N-terminal 50-100 amino acids may be important for the replication function of T antigen, the initiator protein of simian virus 40 (SV40). We have investigated this possibility using the T antigen related D2 protein in several biochemical assay systems. D2 ...


    pub_type: 杂志文章


    authors: Klausing K,Scheffner M,Scheidtmann KH,Stahl H,Knippers R

    更新日期:1989-03-07 00:00:00