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8613385 | Coordinate synthesis and turnover of heat shock proteins in Borrelia burgdorferi: degradation of DnaK during recovery from heat shock. | The synthesis and turnover of heat shock proteins (Hsps) by Borrelia burgdorferi, the Lyme disease spirochete, was investigated by radiolabeling of whole spirochetes and spheroplasts, comparison of one- and two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and use of immunochemistry. The approx... |
8626329 | Sequence, expression in Escherichia coli, and analysis of the gene encoding a novel intracellular protease (PfpI) from the hyperthermophilic archaeon Pyrococcus furiosus. | A previously identified intracellular proteolytic activity in the hyperthermophilic archaeon Pyrococcus furiosus (I. I. Blumentals, A. S. Robinson, and R. M. Kelly, Appl. Environ. Microbiol. 56:1992-1998, 1990) was found to be a homomultimer consisting of 18.8-kDa subunits. Dissociation of this native P. furiosus prote... |
8610899 | The effect of a cyclodextrin vehicle on the cardiovascular profile of propofol in rats. | We studied the aqueous solution of propofol dissolved in hydroxypropyl-beta-cyclodextrin (HP beta CD) 20% to determine whether the cardiovascular profile differed from that measured for propofol prepared in Intralipid 10% (Diprivan). Conscious male rats were given an intravenous bolus of propofol, 5.0 mg/kg, the minimu... |
8628299 | Interactions among SR proteins, an exonic splicing enhancer, and a lentivirus Rev protein regulate alternative splicing. | We examine here the roles of cellular splicing factors and virus regulatory proteins in coordinately regulating alternative splicing of the tat/rev mRNA of equine infectious anemia virus (EIAV). This bicistronic mRNA contains four exons; exons 1 and 2 encode Tat, and exons 3 and 4 encode Rev. In the absence of Rev expr... |
8627814 | Assessment of the serological relatedness of genital human papillomaviruses by hemagglutination inhibition. | To assess the potential for cross-protection among genital human papillomavirus (HPV) types in virus-like particle (VLP)-based vaccinations, inhibition of HPV VLP-mediated hemagglutination by rabbit antisera raised against HPV type 6b (HPV-6b), HPV-11, HPV-16, HPV-18, HPV-31, HPV-33, and HPV-45 was analyzed. Only highl... |
8627805 | Subcellular localization of Aleutian mink disease parvovirus proteins and DNA during permissive infection of Crandell feline kidney cells. | Confocal microscopy allowed us to localize viral nonstructural (NS) and capsid (VP) proteins and DNA simultaneously in cells permissively infected with Aleutian mink disease parvovirus (ADV). Early after infection, NS proteins colocalized with viral DNA to form intranuclear inclusions, whereas VP proteins formed hollow... |
8627748 | Nuclear trafficking of influenza virus ribonuleoproteins in heterokaryons. | The influenza virus nucleoprotein (NP), matrix protein (M1), and ribonucleoproteins (vRNPs) undergo regulated nuclear import and export during infection. Their trafficking was analyzed by using interspecies heterokaryons containing nuclei from infected and uninfected cells. Under normal conditions, it was demonstrated ... |
27715034 | A Switchable Hybrid [2]-Catenane Based on Transition Metal Complexation and π-Electron Donor-Acceptor Interactions. | A bimodal [2]-catenane has been synthesized via a copper(I) templated synthesis. The compound contains both a transition metal coordination site and a set of π-electron rich and π-electron deficient aromatic units suitable for the formation of acceptor-donor complexes. Each constituent ring is thus different from the o... |
21619151 | Extraction of Volatile PAHs from Air by Use of Solid Cyclodextrin. | An approach for extraction of polycyclic aromatic hydrocarbons (PAHs) from air using solid cyclodextrin is presented. A comparison study in which β-cyclodextrin is replaced by α-cyclodextrin provides evidence that β-cyclodextrin extracts vapor phase PAHs by formation of inclusion complexes rather than by association or... |
16535286 | Characterization of Tetragenococcus halophila Populations in Indonesian Soy Mash (Kecap) Fermentation. | Chinese- and Japanese-type fermented soy sauces are made of different plant materials. The lactic acid bacterium Tetragenococcus halophila is present and grows in both types. On the basis of the difference in sugar composition and content in the plant materials, differences in the populations of T. halophila bacteria w... |
11666483 | Structural Criteria for the Rational Design of Selective Ligands. 2. Effect of Alkyl Substitution on Metal Ion Complex Stability with Ligands Bearing Ethylene-Bridged Ether Donors. | A novel approach is presented for the application and interpretation of molecular mechanics calculations in ligand structural design. The methodology yields strain energies that (i) provide a yardstick for the measurement of ligand binding site organization for metal ion complexation and (ii) allow the comparison of an... |
11666475 | Transition Metal Complexes of p-Sulfonatocalix[5]arene. | The X-ray crystal structure of the p-sulfonatocalix[5]arene(5)(-) anion (1b) in the form of the dimeric hydrate Na(10)[p-sulfonatocalix[5]arene](2).33.5H(2)O (2) is reported. The reactions of 1b with a number of transition metal salts to form transition metal bridged bis(calixarene) inclusion complexes have also been i... |
11666435 | Second-Sphere Coordination of Ferrioxamine B and Association of Deferriferrioxamine B, CH(3)(CH(2))(4)NH(3)(+), NH(4)(+), K(+), and Mg(2+) with Synthetic Crown Ethers and the Natural Ionophores Valinomycin and Nonactin in Chloroform. | The interaction of ferrioxamine B, FeHDFB(+), through a protonated amine side chain, with various host ionophore structures to form a host-guest complex in the second coordination shell has been investigated. Host-guest association constants (K(a)) in water saturated chloroform are reported for synthetic crown ethers w... |
11666414 | Lanthanide Structures, Coordination, and Extraction Investigations of a 1,3-Bis(diethyl amide)-Substituted Calix[4]arene Ligand. | The synthesis and structure determinations of lanthanum, samarium, ytterbium, and lutetium complexes of 5,11,17,23-tetra-tert-butyl-25,27-bis((diethylcarbamoyl)methoxy)-26,28-dihydroxycalix[4]arene (L) are described. The four structures display similar characteristics with the trivalent lanthanide cation being encapsul... |
15045463 | Simultaneous determination of In(III) and Cd(II) by differential pulse polarography in the presence of poly beta-cyclodextrin. | The difference in the peak potentials of In(III) and Cd(II), whose reduction potentials are very close to each other, becomes large in the presence of poly beta-cyclodextrin in sodium perchlorate medium. The relationships between the peak currents for these two ions and their concentrations are linear, suggesting that ... |
8835775 | Molecular recognition via face center representation of a molecular surface. | While docking methodologies are now frequently being developed, a careful examination of the molecular surface representation, which necessarily is employed by them, is largely overlooked. There are two important aspects here that need to be addressed: how the surface representation quantifies surface complementarity, ... |
8813717 | Hemolytic anemias due to disorders of red cell membrane skeleton. | During the past 10 years, knowledge of the composition, function and supramolecular assembly of the red cell membrane has been greatly expanded by progress in molecular and cell biology. Detailed information on the organization of membrane cytoskeletal proteins and their molecular characterization has allowed us to cor... |
8793210 | Electron microscopic in situ hybridization (EMISH) against synaptonemal complex-associated chromatin. | Mouse synaptonemal complexes (SCs) were hybridized with a telomeric DNA probe. The biotinylated probe was detected with antibodies conjugated to 5-nm colloidal gold and observed in the transmission electron microscope. The distribution of the probe was clearly marked by clusters of the gold particles and the ultrastruc... |
8793209 | Evidence for a megareplicon covering megabases of centromeric chromosome segments. | We have analysed the replication of the heterochromatic megachromosome that was formed de novo by a large-scale amplification process initiated in the centromeric region of mouse chromosome 7. The megachromosome is organized into amplicons approximately 30 Mb in size, and each amplicon consists of two large inverted re... |
8793208 | De novo chromosome formations by large-scale amplification of the centromeric region of mouse chromosomes. | Chromosomes formed de novo which originated from the centromeric region of mouse chromosome 7, have been analysed. These new chromosomes were formed by apparently similar large-scale amplification processes, and are organized into amplicons of approximately 30 Mb. Centromeric satellite DNA was found to be the constant ... |
8793207 | Zoo-FISH delineates conserved chromosomal segments in horse and man. | Human chromosome specific libraries (CSLs) were individually applied to equine metaphase chromosomes using the fluorescence in situ hybridization (FISH) technique. All CSLs, except Y, showed painting signals on one or several horse chromosomes. In total 43 conserved chromosomal segments were painted. Homoeology could n... |
8793206 | Comparative FISH mapping of bovine cosmids to reindeer chromosomes demonstrates conservation of the X-chromosome. | Three X chromosome-specific bovine cosmids were used for fluorescence in situ hybridization mapping on reindeer (Rangifer tarandus) chromosomes, to test whether such large genomic clones could be used for comparative mapping across distantly related species. All three cosmids showed distinct unique hybridization sites ... |
8793205 | How do Alliaceae stabilize their chromosome ends in the absence of TTTAGGG sequences? | The Arabidopsis-type telomeric repeats (5'-TTTAGGG-3) are highly conserved. In most families of different plant phyla they represent the basic sequence of telomeres that stabilize and protect the chromosome termini. The results presented here show that Alliaceae and some related liliaceous species have no tandemly repe... |
8793204 | High-resolution fluorescence in situ hybridization of RBM- and TSPY-related cosmids on released Y chromatin in humans and pygmy chimpanzees. | Applying two-colour fluorescence in situ hybridization (FISH) we simultaneously hybridized RBM- and TSPY-related cosmids to Y chromosomes in prophase and to released Y chromatin in interphase nuclei of man and pygmy chimpanzee. Whereas, even on prophasic Y chromosomes, no resolution of the overlapping RBM and TSPY sign... |
8793203 | Painting rye B chromosomes in wheat: interphase chromatin organization, nuclear disposition and association in plants with two, three or four Bs. | The B chromosomes (Bs) of rye (Secale cereale) have been studied at interphase in terms of their chromatin organization, patterns of nuclear disposition and physical association in plants with two, three, and four Bs. The study was made in the Lindström strain of hexaploid wheat, which carries the rye Bs as an addition... |
8793202 | Differential immunostaining of plant chromosomes by antibodies recognizing acetylated histone H4 variants. | Metaphase chromosomes of Vicia faba were exposed to antibodies recognizing defined acetylated isoforms of histone H4. After indirect immunostaining with antibodies directed against H4 acetylated on lysines 5, 8 and 12 respectively, the entire chromosome complement was labelled. The brightest signal appeared at the nucl... |
8793201 | Evolution of dosage compensation. | In polytene chromosome squashes from the fruit fly Drosophila melanogaster, the single, dosage-compensated X chromosome in males can be distinguished from the autosomes by the presence of an isoform of histone H4 acetylated at lysine 16, H4.Ac16. We have used H4.Ac16 as a marker to examine the evolving relationship bet... |
8793200 | Labelling telomeres of cereals, grasses and clover by primed in situ DNA labelling. | Primed in situ DNA labelling (PRINS) labels the telomeres of Avena, Triticum, Secale, Hordeum, Lolium, Festuca and Trifolium when primers are used that correspond to the repeat unit of Arabidopsis telomeres. There are interstitial sites labelled in a Lolium x Festuca hybrid. |
8793199 | Heterochromatin and ribosomal genes in Asellus aquaticus (Crust. Isop.). | In the present investigation chromosomal preparations of Asellus aquaticus were sequentially stained with chromomycin A3 to reveal the heterochromatic areas, hybridized in situ with rDNA probes in order to map the ribosomal genes and finally silver stained to check the transcriptional activity of these genes. The resul... |
8790990 | Reduction of postischemic brain damage and memory deficits following treatment with the selective adenosine A1 receptor agonist. | Agonists of adenosine A1 receptors have been frequently proposed as candidates for clinical development in treatment of cerebral ischemia and stroke. Numerous experimental studies have shown that pre- and postischemic administration of these drugs results in a very significant reduction of postischemic brain damage. Ho... |
8743969 | The modulation of brain dopamine and GABAA receptors by estradiol: a clue for CNS changes occurring at menopause. | 1. Tardive dyskinesia is more important in postmenopausal women than men of comparable age and a peak of first episodes of schizophrenia is observed in postmenopausal women. The effect of ovariectomy (2 weeks or 3 months) in rats was investigated as a model of decreased gonadal function associated with menopause. 2. Fr... |
8740367 | Pigment-pigment interactions and energy transfer in the antenna complex of the photosynthetic bacterium Rhodopseudomonas acidophila. | <h4>Background</h4>Photosynthesis starts with the absorption of solar radiation by antenna pigment molecules. In purple bacteria these chromophores, (bacteriochlorophyll a and carotenoid) are embedded in the membrane; they are non-covalently bound to apoproteins which have the ability to modulate the chromophores' abso... |
8740526 | Molecular dissection of the nuclear pore complex. | The nuclear pore complex (NPC) is an approximately 120 megadalton (MDa) supramolecular assembly embedded in the double-membraned nuclear envelope (NE) that mediates bidirectional molecular trafficking between the cytoplasm and the nucleus of interphase eukaryotic cells. The structure of the NPC has been studied extensi... |
8741211 | Integration of titin into the sarcomeres of cultured differentiating human skeletal muscle cells. | Titin is amongst the first sarcomeric proteins to be detected in the process of myofibrillogenesis of striated muscle. During embryogenesis this high molecular weight protein is initially observed in a punctate staining pattern in immunohistochemical studies, while during maturation titin organizes into a cross-striate... |
8718673 | The relative roles of specific N- and C-terminal phosphorylation sites in the disassembly of intermediate filament in mitotic BHK-21 cells. | Previously we identified p34cdc2 as one of two protein kinases mediating the hyperphosphorylation and disassembly of vimentin in mitotic BHK-21 cells. In this paper, we identify the second kinase as a 37 kDa protein. This p37 protein kinase phosphorylates vimentin on two adjacent residues (thr-457 and ser-458) which ar... |
8728650 | Use of macromolecular assemblies as expression systems for peptides and synthetic vaccines. | The past decade has witnessed the development of numerous systems for the presentation of antigens on the surface of self-assembling macromolecules. Although the sites for insertion were initially chosen empirically, the determination of the three-dimensional structures of a number of carrier macromolecules has enabled... |
8785722 | Evaluation of plasma alpha-2-macroglobulin and interactions with tumour necrosis factor-alpha in horses with endotoxemic signs. | The electrophoretic position and behavior of the native and activated forms of equine plasma alpha-2-macroglobulin (alpha 2M) were characterized and compared to human alpha 2M by nondenaturing polyacrylamide-gel electrophoresis (PAGE). Plasma alpha 2M was also compared between 6 normal horses and 6 horses with clinical... |
8672460 | Structure of cyclodextrin glycosyltransferase complexed with a maltononaose inhibitor at 2.6 angstrom resolution. Implications for product specificity. | Crystals of the Y195F mutant of cyclodextrin glycosyltransferase from Bacillus circulans strain 251 were subjected to a double soaking procedure, in which they were first soaked in a solution containing the inhibitor acarbose and subsequently in a solution containing maltohexaose. The refined structure of the resulting... |
8672434 | Reversible oligonucleosome self-association: dependence on divalent cations and core histone tail domains. | Regularly spaced nucleosomal arrays equilibrate between unfolded and highly folded conformations in <2 mM MgCl2, and self-associate above 2 mM MgCl2 [Schwarz, P. M., & Hansen, J. C. (1994) J. Biol. Chem. 269, 16284-16289]. Here we use analytical and differential sedimentation techniques to characterize the molecular me... |
8666910 | Exochelins of Mycobacterium tuberculosis remove iron from human iron-binding proteins and donate iron to mycobactins in the M. tuberculosis cell wall. | To multiply and cause disease in the host, Mycobacterium tuberculosis must acquire iron from the extracellular environment at sites of replication. To do so, the bacterium releases high-affinity iron-binding siderophores called exochelins. In previous studies, we have described the purification and characterization of ... |
8845751 | Prediction of protein complexes using empirical free energy functions. | A long sought goal in the physical chemistry of macromolecular structure, and one directly relevant to understanding the molecular basis of biological recognition, is predicting the geometry of bimolecular complexes from the geometries of their free monomers. Even when the monomers remain relatively unchanged by comple... |
8845746 | Complement factor D, a novel serine protease. | Factor D is unique among serine proteases in that it requires neither enzymatic cleavage for expression of proteolytic activity nor inactivation by a serpin for its control. Regulation of factor D activity is instead attained by a novel mechanism that depends on reversible conformational changes for expression and cont... |
8694272 | Characterization of Meibomian gland innervation in the cynomolgus monkey (Macaca fascicularis). | To characterize the innervation of the cynomolgus monkey (Macaca fascicularis) Meibomian (tarsal) glands, upper lids of six cynomolgus monkeys were investigated with electronmicroscopical and double-labeling immunocytochemical methods. Antibodies against calcitonin gene-related peptide (CGRP), dopamine-beta-hydroxylase... |
8785357 | Surface engineering: optimization of antigen presentation in self-assembled monolayers. | The formation of self-assembled monolayers (SAMs) on gold surfaces containing an antigenic peptide (NANP)6 and HS(CH2)11OH, and the specific binding of a monoclonal antibody to these layers were investigated by surface plasmon resonance (SPR). Peptides were synthesized by solid-state phase synthesis and were linked eit... |
8785354 | Quaternary structure dynamics and carbon monoxide binding kinetics of hemoglobin valency hybrids. | The kinetics of CO binding and changes in quaternary structure for symmetric valency hybrids of human hemoglobin have been extensively studied by laser photolysis techniques. Both alpha+beta and alpha beta+ hybrids were studied with five different ferric ligands, over a broad range of CO concentrations and photolysis l... |
8785349 | Action at a distance in supercoiled DNA: effects of sequence on slither, branching, and intramolecular concentration. | We report a computer modeling study of DNA supercoiling in model plasmids over the size range of 140-1260 bp. We used a computer model with basepair resolution. Molecular dynamics was used to produce ensembles at 300 K and to investigate intramolecular motions. The plasmid models varied by their sequence. The sequence ... |
8785346 | Force generation, work, and coupling in molecular motors. | A mechanism is proposed for molecular motors in which force is generated by a protein conformational change driven by binding energy (in muscle, that of myosin with actin as well as with ATP, ADP, or Pi). Work, the product of the force generated by one myosin or kinesin molecule (F) and the distance over which it acts ... |
8785339 | Immuno-atomic force microscopy of purple membrane. | The atomic force microscope is a useful tool for imaging native biological structures at high resolution. In analogy to conventional immunolabeling techniques, we have used antibodies directed against the C-terminus of bacteriorhodopsin to distinguish the cytoplasmic and extracellular surface of purple membrane while i... |
8785337 | Hydrogen bond stabilities in membrane-reconstituted alamethicin from amide-resolved hydrogen-exchange measurements. | Amide-resolved hydrogen-deuterium exchange-rate constants were measured for backbone amides of alamethicin reconstituted in dioleoylphosphatidylcholine vesicles by an exchange-trapping method combined with high-resolution nuclear magnetic resonance spectroscopy. In vesicles containing alamethicin at molar ratios betwee... |
8785335 | Thermotropic phase behavior and stability of monosialoganglioside micelles in aqueous solution. | The thermotropic phase behavior of monosialoganglioside in a dilute aqueous dispersion at pH 6.8 was measured by using synchrotron radiation small-angle x-ray scattering and was analyzed by a shell-modeling method. Previous calorimetric studies on ganglioside systems have shown quite different thermotropic behaviors fr... |
8785325 | Ion channel stabilization of synthetic alamethicin analogs by rings of inter-helix H-bonds. | Rings of inter-helix H-bonds due to Gln at position 7, a highly conserved residue in all pore-forming peptaibols, have been suggested to play an important role in the stabilization of alamethicin channels. In an attempt to test this hypothesis, experimental studies have been undertaken on four synthetic alamethicin non... |
8651499 | A sulfated cyclodextrin chiral stationary phase for high-performance liquid chromatography. | A new sulfated beta-cyclodextrin (degree of substitution approximately 13-14/cyclodextrin) bonded chiral stationary phase (CSP) for high-performance liquid chromatography is introduced. The novel CSP was used to resolve a number of enantiomeric pairs, including antihistamines, antidepressants and phenylhydantoins, usin... |
8651498 | Application of sulfated cyclodextrins to chiral separations by capillary zone electrophoresis. | Mixtures of randomly substituted sulfated cyclodextrins (degree of substitution, approximately 7-10) were successfully used as chiral additives for the enantioseparation of 56 compounds of pharmaceutical interest, including anesthetics, antiarrhythmics, antidepressants, anticonvulsants, antihistamines, antihypertensive... |
8657101 | A novel interferon regulatory factor family transcription factor, ICSAT/Pip/LSIRF, that negatively regulates the activity of interferon-regulated genes. | We have isolated a novel cDNA clone encoding interferon (IFN) consensus sequence-binding protein in adult T-cell leukemia cell line or activated T cells (ICSAT); this protein is the human homolog of the recently cloned Pip/LSIRF. ICSAT is structurally most closely related to the previously cloned ICSBP, a member of the... |
8666866 | [Prognosis of the surgical treatment for non-Hodgkin lymphoma originating from chronic tuberculous empyema--analysis of 11 cases with pleuropneumonectomy]. | In total 19 cases of non-Hodgkin lymphoma originating from the wall of chronic tuberculous empyema, pleuropneumonectomeic were performed since 1979, with the aim of total cures for not only lymphoma but empyema in 11 cases. Of these cases extraresections (5 of thoracic cages, 4 of diaphragms, 2 of axillar lymph nodes, ... |
8644729 | Glycine substitutions in the triple-helical region of type VII collagen result in a spectrum of dystrophic epidermolysis bullosa phenotypes and patterns of inheritance. | The dystrophic forms of epidermolysis bullosa (DEB) are characterized by fragility of the skin and mucous membranes. DEB can be inherited in either an autosomal dominant or autosomal recessive pattern, and the spectrum of clinical severity is highly variable. The unifying diagnostic hallmark of DEB is abnormalities in ... |
8829532 | Synthesis of neohesperidin glycosides and naringin glycosides by cyclodextrin glucanotransferase from an alkalophilic Bacillus species. | Cyclodextrin glucanotransferase from an alkalophilic Bacillus species produced neohesperidin monoglucoside and a series of its maltooligoglucosides by transglycosylation with neohesperidin as an acceptor and soluble starch as a donor. As the reaction using beta-CD as a donor at an alkaline pH was very effective for sol... |
8636027 | Cell-associated glucans of Burkholderia solanacearum and Xanthomonas campestris pv. citri: a new family of periplasmic glucans. | The cell-associated glucans produced by Burkholderia solanacearum and Xanthomonas campestris pv. citri were isolated by trichloroacetic acid treatment and gel permeation chromatography. The compounds obtained were characterized by compositional analysis, matrix-assisted laser desorption ionization mass spectrometry, an... |
8633060 | Purified inositol hexakisphosphate kinase is an ATP synthase: diphosphoinositol pentakisphosphate as a high-energy phosphate donor. | Diphosphoinositol pentakisphosphate (PP-IP5) and bis(diphospho)inositol tetrakisphosphate (bis-PP-IP4) are recently identified inositol phosphates that possess pyrophosphate bonds. We have purified an inositol hexakisphosphate (IP6) kinase from rat brain supernatants. The pure protein, a monomer of 54 kDa, displays hig... |
8633016 | DNA transport by a type II topoisomerase: direct evidence for a two-gate mechanism. | Recent biochemical and crystallographic results suggest that a type II DNA topoisomerase acts as an ATP-modulated clamp with two sets of jaws at opposite ends: a DNA-bound enzyme can admit a second DNA through one set of jaws; upon binding ATP, this DNA is passed through an enzyme-mediated opening in the first DNA and ... |
8633009 | Mapping protein-protein interactions by affinity-directed mass spectrometry. | A precise and rapid method for identifying sites of interaction between proteins was demonstrated; the basis of the method is direct mass spectrometric readout from the complex to determine the specific components of the proteins that interact--a method termed affinity-directed mass spectrometry. The strategy was used ... |
8670127 | Evidence for an inhibitory feedback loop regulating simian virus 40 large T-antigen fusion protein nuclear transport. | Nuclear protein import is central to eukaryotic cell function. It is dependent on ATP, temperature and cytosolic factors, and requires specific targeting sequences called nuclear localization signals (NLSs). Nuclear import kinetics was studied in vitro using digitonin-permeabilized cells of the HTC rat hepatoma cell li... |
8611532 | Probing the function of Asp128 in the lower molecular weight protein-tyrosine phosphatase-catalyzed reaction. A pre-steady-state and steady-state kinetic investigation. | The role of Asp128 in the catalytic mechanism of the low Mr protein-tyrosine phosphatase (PTPase) from the fission yeast Schizosaccharomyces pombe has been investigated by a combination of site-directed mutagenesis and pre-steady-state and steady-state kinetic analysis. The corresponding aspartic acid in the bovine enz... |
8620912 | An epidemiological investigation of Norwalk virus infection in South Africa. | A study was carried out to determine the incidence and seroprevalence of Norwalk virus (NV) in the Pretoria area, South Africa, using a recombinant NV (rNV) immunoassay for the detection of serum IgG antibodies. Maternal antibody was detectable in infants' sera up to approximately 6 months of age. Infection with NV was... |
8617245 | Transfer RNA-dependent cognate amino acid recognition by an aminoacyl-tRNA synthetase. | An investigation of the role of tRNA in the catalysis of aminoacylation of Escherichia coli glutaminyl-tRNA synthetase (GlnRS) has revealed that the accuracy of specific interactions between GlnRS and tRNAGln determines amino acid affinity. Mutations in GlnRS at D235, which makes contacts with nucleotides in the accept... |
8617242 | The human papillomavirus type 16 E7 gene product interacts with and trans-activates the AP1 family of transcription factors. | The E7 gene product of human papillomavirus type 16 (HPV16) binds to the retinoblastoma gene product (pRb) and dissociates pRb-E2F complexes. However, the observation that the ability of E7 to bind pRb is not required for the HPV16-induced immortalization of primary keratinocytes prompted a search for other cellular fa... |
8617220 | Muscle wasting and dedifferentiation induced by oxidative stress in a murine model of cachexia is prevented by inhibitors of nitric oxide synthesis and antioxidants. | Muscle wasting is a critical feature of patients afflicted by AIDS or cancer. In a murine model of muscle wasting, tumor necrosis factor alpha (TNF alpha) induces oxidative stress and nitric oxide synthase (NOS) in skeletal muscle, leading to decreased myosin creatinine phosphokinase (MCK) expression and binding activi... |
8612595 | A preference of histone H1 for methylated DNA. | We have identified a clear preference of histone H1 for CpG-methylated DNA, irrespective of DNA sequence. The conditions under which this preference is observed allowed cooperative binding of H1; the H1-DNA complexes formed were shown earlier to be 'tramlines' of two DNA duplexes bridged by an array of H1 molecules, an... |
8615827 | Structure of photosystem II in spinach thylakoid membranes: comparison of detergent-solubilized and native complexes by electron microscopy. | 1. Electron microscopy of solubilized photosystem II (PSII) complexes and PSII in spinach thylakoid membranes has been carried out and the results have been compared with data obtained from ordered two-dimensional arrays of PSII. Membrane-bound PSII is roughly rectangular (17.6 nm x 14.1 nm) with a central stain cavity... |
8615800 | Peptide models for membrane channels. | Peptides may be synthesized with sequences corresponding to putative transmembrane domains and/or pore-lining regions that are deduced from the primary structures of ion channel proteins. These can then be incorporated into lipid bilayer membranes for structural and functional studies. In addition to the ability to inv... |
8613986 | The solution structure of bovine ferricytochrome b5 determined using heteronuclear NMR methods. | The solution structure of a recombinant form of cytochrome b5 containing 104 amino acid residues has been determined using three-dimensional NMR spectroscopy. Using protein enriched in 15N the majority of the polypeptide backbone resonances have been assigned to reveal numerous chemical shift differences to those repor... |
8611420 | Characterisation of antimitotic products from marine organisms that disorganise the microtubule network: ecteinascidin 743, isohomohalichondrin-B and LL-15. | The effect of selected marine compounds with anti-tumoral activity on the cell microtubule network was tested by immunofluorescence analyses, or by other in vitro analyses involving competition with colchicine or with GTP for tubulin binding and tubulin polymerisation, studies that were carried out in parallel with oth... |
8627902 | Inhibition of vein graft intimal and medial thickening by periadventitial application of a sulfated carbohydrate polymer. | <h4>Purpose</h4>The purpose of this study was to determine whether the wall thickening observed in vein grafts after they were placed into the arterial circulation could be inhibited by periadventitial delivery of an insoluble sulfated polymer of beta-cyclodextrin (P-CDS) capable of tightly binding heparin binding grow... |
8925900 | Dependence of rat liver CMP-N-acetylneuraminate:GM1 sialyltransferase (SAT IV) activity on the ceramide composition of GM1 ganglioside. | The dependence of CMP-N-acetylneuraminate:GM1 sialyltransferase (SAT IV) activity of rat liver Golgi apparatus on GM1 ganglioside ceramide composition was evaluated. SAT IV activity was assayed on GM1 molecular species carrying homogeneous ceramide moieties containing long chain bases of different length (18 or 20 C at... |
8611495 | Solvation energies of amino acid side chains and backbone in a family of host-guest pentapeptides. | Octanol-to-water solvation free energies of acetyl amino amides (Ac-X-amides) [Fauchère, J.L., & Pliska, V. (1983) Eur. J. Med. Chem. --Chim. Ther. 18,369] form the basis for computational comparisons of protein stabilities by means of the atomic solvation parameter formalism of Eisenberg and McLachlan [(1986) Nature 3... |
8609173 | Inhibition of laminin alpha 1-chain expression leads to alteration of basement membrane assembly and cell differentiation. | The expression of the constituent alpha 1 chain of laminin-1, a major component of basement membranes, is markedly regulated during development and differentiation. We have designed an antisense RNA strategy to analyze the direct involvement of the alpha 1 chain in laminin assembly, basement membrane formation, and cel... |
8622970 | Creation of drug-specific herpes simplex virus type 1 thymidine kinase mutants for gene therapy. | Herpes simplex virus type 1 (HSV-1) thymidine kinase is currently used as a suicide agent in the gene therapy of cancer. This therapy is based on the preferential phosphorylation of nucleoside analogs by tumor cells expressing HSV-1 thymidine kinase. However, the use of HSV-1 thymidine kinase is limited in part by the ... |
8622961 | Detection and localization of individual antibody-antigen recognition events by atomic force microscopy. | A methodology has been developed for the study of molecular recognition at the level of single events and for the localization of sites on biosurfaces, in combining force microscopy with molecular recognition by specific ligands. For this goal, a sensor was designed by covalently linking an antibody (anti-human serum a... |
8622940 | Improved adenovirus packaging cell lines to support the growth of replication-defective gene-delivery vectors. | Adenovirus (Ad) vectors have been extensively used to deliver recombinant genes to a great variety of cell types in vitro and in vivo. Ad-based vectors are available that replace the Ad early region 1 (E1) with recombinant foreign genes. The resultant E1-deleted vectors can then be propagated on 293 cells, a human embr... |
8621779 | The urokinase receptor (CD87) facilitates CD11b/CD18-mediated adhesion of human monocytes. | Urokinase receptors (uPAR; CD87) from complexes with complement receptor 3 (CR3) (CD11b/CD18), a beta2 integrin. In this study, we sought to determine if this association modulates the adhesive function of CR3. Both CR3 and uPAR concentrate at the ventral surface of fibrinogen-adherent human monocytes, and CR3-uPAR cou... |
8614800 | Evaluating electrostatic contributions to binding with the use of protein charge ladders. | Electrostatic interactions between charges on ligands and charges on proteins that are remote from the binding interface can influence the free energy of binding (delta Gb). The binding affinities between charged ligands and the members of a charge ladder of bovine carbonic anhydrase (CAII) constructed by random acetyl... |
8611404 | Thrombin enhances the adhesion and migration of human colon adenocarcinoma cells via increased beta 3-integrin expression on the tumour cell surface and their inhibition by the snake venom peptide, rhodostomin. | The interactions between tumour cells and the microvasculature, including the adhesion of tumour cells to endothelium and extracellular matrix (ECM) as well as their migratory ability, are prerequisites for metastasis to occur. In this study we showed that thrombin is capable of enhancing in vitro tumour cell metastati... |
8614635 | Differential discrimination of DNA polymerase for variants of the non-standard nucleobase pair between xanthosine and 2,4-diaminopyrimidine, two components of an expanded genetic alphabet. | Mammalian DNA polymerases alpha and epsilon, the Klenow fragment of Escherichia coli DNA polymerase I and HIV-1 reverse transcriptase (RT) were examined for their ability to incorporate components of an expanded genetic alphabet in different forms. Experiments were performed with templates containing 2'-deoxyxanthosine... |
8614632 | The width of the minor groove affects the binding of the bisquaternary heterocycle SN-6999 to duplex DNA. | A complex between d(GGGAAAAACGG).d(CCGTTTTTCCC) and the minor groove binding drug SN-6999 has been studied by 1H nuclear magnetic resonance spectroscopy. The drug is found to bind in the d(A)5 tract, but with interactions extending one residue in the 3'-direction along each strand. Doubling of resonances in the complex... |
8614027 | Postinjury multiple organ failure: a bimodal phenomenon. | To better define the epidemiology of postinjury multiple organ failure (MOF), we prospectively evaluated 457 high-risk trauma patients who survived more than 48 hours. Overall, 70 (15%) developed MOF. In 27 (39%) patients, the occurrence was early, while in 43 (61%) patients the presentation was delayed. At presentatio... |
8613960 | Antithrombotic effects of TAK-029, a novel GPIIb/IIIa antagonist, in guinea pigs: comparative studies with ticlopidine, clopidogrel, aspirin, prostaglandin E1 and argatroban. | The antithrombotic and bleeding time (BT)-prolonging effects of TAK-029, a novel glycoprotein IIb/IIIa antagonist, were characterized and compared with those of conventional antithrombotic agents in guinea pigs. TAK-029 potently inhibited the binding of fibrinogen and von Willebrand factor to purified human GPIIb/IIIa ... |
8642690 | Effective ex vivo neutralization of human immunodeficiency virus type 1 in plasma by recombinant immunoglobulin molecules. | We tested the ability of human monoclonal antibodies (immunoglobulin G1b12 [IgG1b12] and 19b) and CD4-based molecules (CD4-IgG2 and soluble CD4 [sCD4]) to neutralize human immunodeficiency virus type 1 directly from the plasma of seropositive donors in an ex vivo neutralization assay. IgG1b12 and CD4-IgG2, at concentra... |
8642686 | The Epstein-Barr virus-encoded nuclear antigen EBNA-5 accumulates in PML-containing bodies. | EBNA-5 is one of the Epstein-Barr virus (EBV)-encoded nuclear proteins required for immortalization of human B lymphocytes. In the nuclei of EBV-transformed lymphoblastoid cell lines EBNA-5 is preferentially targetted to distinct nuclear foci. Previously we have shown (W.Q. Jiang, L. Szekely, V. Wendel-Hansen, N. Ringe... |
8642641 | Identification of domains in rubella virus genomic RNA and capsid protein necessary for specific interaction. | In rubella virus-infected cells, genomic 40S and subgenomic 24S RNAs are present in the cytoplasm of infected cells. However, encapsidation by rubella virus capsid protein is specific for 40S genomic RNA. As a first step toward understanding the assembly of rubella virus nucleocapsid at the molecular level, the interac... |
8642633 | Identification and characterization of a small modular domain in the herpes simplex virus host shutoff protein sufficient for interaction with VP16. | The herpes simplex virus transactivator VP16 and the virion host shutoff protein vhs are viral structural components that direct the activation of immediate-early gene expression and the arrest of host protein synthesis, respectively, during an infection. Recent studies show that VP16 and vhs physically interact with e... |
8642632 | Adenovirus type 5 and 7 capsid chimera: fiber replacement alters receptor tropism without affecting primary immune neutralization epitopes. | The efficient uptake of adenovirus into a target cell is a function of adenovirus capsid proteins and their interaction with the host cell. The capsid protein fiber mediates high-affinity attachment of adenovirus to the target cell. Although the cellular receptor(s) for adenovirus is unknown, evidence indicates that a ... |
8609897 | Glutamate residues in the second extracellular loop of the human A2a adenosine receptor are required for ligand recognition. | The A2a adenosine receptor, a member of the G protein-coupled receptor family, is important in the regulation of dopaminergic pathways of the brain and in platelet and cardiovascular functions. In this study, the role of extracellular loops in ligand binding to the human A2a receptor was explored through site-directed ... |
8610155 | Direct measurement of salt-bridge solvation energies using a peptide model system: implications for protein stability. | The solvation energies of salt bridges formed between the terminal carboxyl of the host pentapeptide AcWL- X-LL and the side chains of Arg or Lys in the guest (X) position have been measured. The energies were derived from octanol-to-buffer transfer free energies determined between pH 1 and pH 9. 13C NMR measurements s... |
8610144 | Imaging of single molecule diffusion. | In recent years observations at the level of individual atoms and molecules became possible by microscopy and spectroscopy. Imaging of single fluorescence molecules has been achieved but has so far been restricted to molecules in the immobile state. Here we provide methodology for visualization of the motion of individ... |
8610143 | In vivo selection of basic region-leucine zipper proteins with altered DNA-binding specificities. | A transcription interference assay was used to generate mutant basic region-leucine zipper proteins with altered DNA-binding specificities. A library of mutants of a CCAAT/enhancer binding protein was constructed by randomizing five DNA-contacting amino acids in the basic region Asn-18, Ala-15, Val-14, Ser-11, and Arg-... |
8610093 | Spectroscopic recognition of guanine dimeric hairpin quadruplexes by a carbocyanine dye. | Isolated guanine quadruplex structures have been described at high resolution both in solution and in the solid state. The existence of this unusual DNA structure in vivo and its biological significance remain to be determined. We describe the binding of 3,3'-diethyloxadicarbocyanine to dimeric hairpin guanine quadrupl... |
8606191 | Dynamics in oxygen-induced changes in S-layer protein synthesis from Bacillus stearothermophilus PV72 and the S-layer-deficient variant T5 in continuous culture and studies of the cell wall composition. | Stable synthesis of the hexagonally ordered (p6) S-layer protein from the wild-type strain of Bacillus stearothermophilus PV72 could be achieved in continuous culture on complex medium only under oxygen-limited conditions when glucose was used as the sole carbon source. Depending on the adaptation of the wild-type stra... |
8606127 | Calixarenes with host-mediated potency in experimental tuberculosis: further evidence that macrophage lipids are involved in their mechanism of action. | Some time ago, it was found that attachment of hydrophilic polyoxyethylene chains to various hydrophobic phenols and alcohols gave water-soluble products which, although inactive in vitro, influenced and experimental tuberculous infection. With short chains the infection was suppressed, and with long chains it was prom... |
8606109 | Identification and characterization of epitopes on the 120-kilodalton surface protein antigen of Rickettsia prowazekii with synthetic peptides. | The 120-kDa surface protein antigens (SPAs) of typhus rickettsiae are highly immunogenic and have been shown to be responsible for the species-specific serological reactions of the typhus group rickettsiae. To study the immunochemistry of these proteins, overlapping decapeptides encompassing the whole protein were synt... |
24227484 | Pheromone specificity inEriocrania semipurpurella (Stephens) andE. sangii (Wood) (Lepidoptera: Eriocraniidae) based on chirality of semiochemicals. | The fifth abdominal segment of femaleEriocrania semipurpurella (Stephens) andE. sangii (Wood) contains a pair of exocrine glands. Hexane extracts of this segment were prepared from both species and analyzed by gas chromatography with simultaneous flame ionization and electroantennographic detection (EAD). For both spec... |
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