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10681500 | Relative orientation of the hemes of the cytochrome bc(1) complexes from Rhodobacter sphaeroides, Rhodospirillum rubrum, and beef heart mitochondria. A linear dichroism study. | The orientation of the chromophores in the cytochrome bc(1) of Rhodospirillum rubrum, Rhodobacter sphaeroides, and beef heart mitochondria is reported. The combination of redox-resolved absorption spectrophotometry and linear dichroism experiments at low temperature allows the determination of the orientation of the th... |
10679379 | Biocatalysis in low-water media: understanding effects of reaction conditions. | The key role played by counter-ions with enzymes in low-water systems has become better appreciated with, for example, large effects on enantioselectivity. In low-dielectric media, counter-ions will associate strongly with charges in the protein or its substrates. Studies of temperature dependence have shown that hard-... |
10679191 | Mode of molecular recognition of L-fucose by fucose-binding legume lectins. | Recognition of cell surface carbohydrate moieties by lectins plays a vital role in many a biological process. Fucosyated residues are often implicated as key recognition markers in many cellular processes. In particular, the aspects of molecular recognition of fucose by fucose-bindinglectins UEA 1 and LTA pose a specia... |
10677502 | Survival function of ERK1/2 as IL-3-activated, staurosporine-resistant Bcl2 kinases. | Bcl2 phosphorylation at Ser-70 may be required for the full and potent suppression of apoptosis in IL-3-dependent myeloid cells and can result from agonist activation of mitochondrial protein kinase C (PKC). Paradoxically, expression of exogenous Bcl2 can protect parental cells from apoptosis induced by the potent PKC ... |
10660685 | Femtosecond resolution of ligand-heme interactions in the high-affinity quinol oxidase bd: A di-heme active site? | Interaction of the two high-spin hemes in the oxygen reduction site of the bd-type quinol oxidase from Escherichia coli has been studied by femtosecond multicolor transient absorption spectroscopy. The previously unidentified Soret band of ferrous heme b(595) was determined to be centered around 440 nm by selective exc... |
10677486 | Self-assembly of large, ordered lamellae from non-bilayer lipids and integral membrane proteins in vitro. | In many biological membranes, the major lipids are "non-bilayer lipids," which in purified form cannot be arranged in a lamellar structure. The structural and functional roles of these lipids are poorly understood. This work demonstrates that the in vitro association of the two main components of a membrane, the non-bi... |
10677288 | Crystal structure of amylomaltase from thermus aquaticus, a glycosyltransferase catalysing the production of large cyclic glucans. | Amylomaltase is involved in the metabolism of starch, one of the most important polysaccharides in nature. A unique feature of amylomaltase is its ability to catalyze the formation of cyclic amylose. In contrast to the well studied cyclodextrin glucanotransferases (CGTases), which synthesize cycloamylose with a ring si... |
10679025 | Monoclonal antibodies to NTF2 inhibit nuclear protein import by preventing nuclear translocation of the GTPase Ran. | Nuclear transport factor 2 (NTF2) is a soluble transport protein originally identified by its ability to stimulate nuclear localization signal (NLS)-dependent protein import in digitonin-permeabilized cells. NTF2 has been shown to bind nuclear pore complex proteins and the GDP form of Ran in vitro. Recently, it has bee... |
10679012 | Detergent-insoluble GPI-anchored proteins are apically sorted in fischer rat thyroid cells, but interference with cholesterol or sphingolipids differentially affects detergent insolubility and apical sorting. | In contrast to Madin-Darby canine kidney cells, Fischer rat thyroid cells deliver the majority of endogenous glycosylphosphatidyl inositol (GPI)-anchored proteins to the basolateral surface. However, we report here that the GPI proteins Placental Alkaline Phosphatase (PLAP) and Neurotrophin Receptor-Placental Alkaline ... |
10679011 | Functional elements within the dynein microtubule-binding domain. | Dynein interacts with microtubules through an ATP-sensitive linkage mapped to a structurally complex region of the heavy chain following the fourth P-loop motif. Virtually nothing is known regarding how binding affinity is achieved and modulated during ATP hydrolysis. We have performed a detailed dissection of the micr... |
10678739 | Calcium, ATP and nuclear pore channel gating. | Nuclear envelope (NE) cisternal Ca2+ and cytosolic ATP are required for nuclear-pore-complex-(NPC-) mediated transport of DNAs, RNAs, transcription factors and other large molecules. Isolated cardiomyocyte nuclei, capable of macromolecular transport (MMT), have intrinsic NPC ion channel behavior. The large ion conducta... |
10675685 | Interaction of p-hydroxybenzoic esters with beta-cyclodextrin. | In the present investigation, the complex formation of beta-cyclodextrin (betaCD) with p-hydroxybenzoic esters (parabens) was studied by mixing betaCD with methyl, ethyl, propyl and butyl parabens, respectively, in aqueous solutions and subjecting the resultant mixtures individually to the following processes: occasion... |
10675681 | Pharmaceutical applications for molecularly imprinted polymers. | Molecular imprinting is a means of introducing sites of specific molecular arrangement into an otherwise uniform polymeric matrix. This is achieved by formation of a pre-polymerisation complex between complementary monomers and the template molecule. Subsequent polymerisation in the presence of a crosslinker, in a poro... |
10675555 | X-ray crystal structure of the YM210W mutant reaction centre from Rhodobacter sphaeroides. | The X-ray crystal structure of a reaction centre from Rhodobacter sphaeroides with a mutation of tyrosine M210 to tryptophan (YM210W) has been determined to a resolution of 2.5 A. Structural conservation is very good throughout the body of the protein, with the tryptophan side chain adopting a position in the mutant co... |
10675332 | N-acyl homoserine lactone binding to the CarR receptor determines quorum-sensing specificity in Erwinia. | Quorum sensing via an N-acyl homoserine lactone (HSL) pheromone controls the biosynthesis of a carbapenem antibiotic in Erwinia carotovora. Transcription of the carbapenem biosynthetic genes is dependent on the LuxR-type activator protein, CarR. Equilibrium binding of a range of HSL molecules, which are thought to acti... |
10675512 | A peptide analogue to a fusion domain within photoreceptor peripherin/rds promotes membrane adhesion and depolarization. | Photoreceptor peripherin/rds promotes membrane fusion, through a putative fusion domain located within the C-terminus (Boesze-Battaglia et al., Biochemistry 37 (1998) 9477-9487). A peptide analogue to this region, PP-5, competitively inhibits peripherin/rds mediated fusion in a cell free assay system. To characterize h... |
10675509 | Cardiolipin, alpha-D-glucopyranosyl, and L-lysylcardiolipin from gram-positive bacteria: FAB MS, monofilm and X-ray powder diffraction studies. | Cardiolipin preparations from Streptococcus B, Listeria welshimeri, Staphylococcus aureus, and a glucosyl and lysyl derivative of cardiolipin were analysed for fatty acid composition and fatty acid combinations. Three different fatty acid patterns are described and up to 17 molecular species were identified in Streptoc... |
10671559 | Cholesterol depletion of enterocytes. Effect on the Golgi complex and apical membrane trafficking. | Intestinal brush border enzymes, including aminopeptidase N and sucrase-isomaltase, are associated with "rafts" (membrane microdomains rich in cholesterol and sphingoglycolipids). To assess the functional role of rafts in the present work, we studied the effect of cholesterol depletion on apical membrane trafficking in... |
10674475 | c-fos expression and redox state of cytochrome oxidase of rat brain in hypoxia. | Hypoxic induction of c-fos was studied in rat brains as a function of the cerebral oxygenation state using near-infrared spectroscopy by which the hemoglobin oxygenation state and redox state of mitochondrial cytochrome oxidase could be monitored noninvasively. Following reoxygenation after hypoxia, the expression of c... |
10674395 | Transcription factors Oct-1 and C/EBPbeta (CCAAT/enhancer-binding protein-beta) are involved in the glutamate/nitric oxide/cyclic-guanosine 5'-monophosphate-mediated repression of mediated repression of gonadotropin-releasing hormone gene expression. | The physiological actions of nitric oxide (NO) as a signaling molecule in endothelial and brain cells and as a toxic molecule used by activated immune cells have been the focus of a wide range of studies. Nevertheless, the downstream effector molecules of this important neuromodulator are not well understood. We have p... |
10669594 | Salmonella enteritidis fimbriae displaying a heterologous epitope reveal a uniquely flexible structure and assembly mechanism. | Two distinct Salmonella fimbrins, AgfA and SefA, comprising thin aggregative fimbriae SEF17 and SEF14, respectively, were each genetically engineered to carry PT3, an alpha-helical 16-amino acid Leishmania T-cell epitope derived from the metalloprotease gp63. To identify regions within AgfA and SefA fimbrins amenable t... |
10666593 | The molecular structure and structural transition of the alpha-helical capsid in filamentous bacteriophage Pf1. | The major coat protein in the capsid of Pf1 filamentous bacteriophage (Inovirus) forms a helical assembly of about 7000 identical protein subunits, each of which contains 46 amino-acid residues and can be closely approximated by a single gently curved alpha-helix. Since the viral DNA occupies the core of the tubular ca... |
10664478 | Complexation of the interferon inducer, bropirimine, with hydroxypropyl-beta-cyclodextrin. | Bropirimine (ABPP) is an orally active immunomodulator that increases endogenous alpha-interferon and other cytokines used clinically against carcinoma in situ of the bladder. The oral absorption of ABPP is poor because its low solubility in water. The purpose of this study is to develop a technological procedure usefu... |
10664477 | Chitosan microspheres with hydrocortisone and hydrocortisone-hydroxypropyl-beta-cyclodextrin inclusion complex. | In the present study, an inclusion complex composed of hydrocortisone acetate (HC) and hydroxypropyl-beta-cyclodextrin (HPbetaCD) was prepared by the spray-drying method. HC alone, HC inclusion complex or HC with HPbetaCD as a physical mixture were incorporated into chitosan microspheres by spray-drying. The inclusion ... |
10662803 | A broad spectrum secreted chemokine binding protein encoded by a herpesvirus. | Chemokines are a family of small proteins that interact with seven-transmembrane domain receptors and modulate the migration of immune cells into sites of inflammation and infection. The murine gammaherpesvirus 68 M3 gene encodes a secreted 44-kD protein with no sequence similarity to known chemokine receptors. We show... |
10662769 | Organization of the yeast Zip1 protein within the central region of the synaptonemal complex. | The yeast Zip1 protein is a component of the central region of the synaptonemal complex (SC). Zip1 is predicted to form an alpha-helical coiled coil, flanked by globular domains at the NH(2) and COOH termini. Immunogold labeling with domain-specific anti-Zip1 antibodies demonstrates that the NH(2)-terminal domain of Zi... |
10660600 | PSK, a novel STE20-like kinase derived from prostatic carcinoma that activates the c-Jun N-terminal kinase mitogen-activated protein kinase pathway and regulates actin cytoskeletal organization. | Degenerate polymerase chain reaction against conserved kinase catalytic subdomains identified 15 tyrosine and serine-threonine kinases expressed in surgically removed prostatic carcinoma tissues, including six receptor kinases (PDGFBR, IGF1-R, VEGFR2, MET, RYK, and EPH-A1), six non-receptor kinases (ABL, JAK1, JAK2, TY... |
10660588 | Structure of the influenza C virus CM2 protein transmembrane domain obtained by site-specific infrared dichroism and global molecular dynamics searching. | The 115-residue protein CM2 from Influenza C virus has been recently characterized as a tetrameric integral membrane glycoprotein. Infrared spectroscopy and site-directed infrared dichroism were utilized here to determine its transmembrane structure. The transmembrane domain of CM2 is alpha-helical, and the helices are... |
10657258 | Crystal structures of human pancreatic alpha-amylase in complex with carbohydrate and proteinaceous inhibitors. | Crystal structures of human pancreatic alpha-amylase (HPA) in complex with naturally occurring inhibitors have been solved. The tetrasaccharide acarbose and a pseudo-pentasaccharide of the trestatin family produced identical continuous electron densities corresponding to a pentasaccharide species, spanning the -3 to +2... |
10657250 | Purification and inhibitory profile of phospholipase A2 inhibitors from Australian elapid sera. | Although the resistance of snakes to their own venom is well known, until now no investigators have examined the serum of Australian snakes. Here we describe the identification and purification of a range of phospholipase A(2) (PLA(2)) inhibitors from the serum of Australian elapids. All PLA(2) inhibitors were composed... |
10657247 | A general kinetic approach to investigation of active-site availability in macromolecular catalysts. | A potentially general kinetic method for the investigation of active-site availability in preparations of macromolecular catalysts was developed. Three kinetic models were considered: (a) the conventional two-step model of enzyme catalysis, where the preparation contains only active catalyst (E(a)) and inert (i.e. non-... |
10657237 | Dye-ligand chromatographic purification of intact multisubunit membrane protein complexes: application to the chloroplast H+-FoF1-ATP synthase. | n-Dodecyl-beta-D-maltoside was used as a detergent to solubilize the ammonium sulphate precipitate of chloroplast F(O)F(1)-ATP synthase, which was purified further by dye-ligand chromatography. Upon reconstitution of the purified protein complex into phosphatidylcholine/phosphatidic acid liposomes, ATP synthesis, drive... |
10657126 | Synthesis of positional-scanning libraries of fluorogenic peptide substrates to define the extended substrate specificity of plasmin and thrombin. | We have developed a strategy for the synthesis of positional-scanning synthetic combinatorial libraries (PS-SCL) that does not depend on the identity of the P1 substituent. To demonstrate the strategy, we synthesized a tetrapeptide positional library in which the P1 amino acid is held constant as a lysine and the P4-P3... |
10656826 | Exploring local and non-local interactions for protein stability by structural motif engineering. | In order to probe the relative contribution of local and non-local interactions to the thermodynamic stability of proteins, we have devised an experimental approach based on a combination of motif engineering and sequence shuffling. Candidate chain segments in an immunoglobulin V(L) domain were identified whose conform... |
10655519 | Tyrosine phosphorylation of the Helicobacter pylori CagA antigen after cag-driven host cell translocation. | Helicobacter pylori strains associated with severe tissue damage and inflammation possess a unique genetic locus, cag, containing 31 genes originating from a distant event of horizontal transfer and retained as a pathogenicity island. The cag system is an Helicobacter-specific type IV secretion engine involved in cellu... |
10655470 | A relation between the principal axes of inertia and ligand binding. | The principal axes of inertia are eigenvectors that can be calculated for any rigid body. We report studies of the position of the principal axes in crystallographically solved protein molecules. We find with high frequency that at least one principal axis penetrates the surface of the respective protein in a region us... |
10653702 | Orienting domains in proteins using dipolar couplings measured by liquid-state NMR: differences in solution and crystal forms of maltodextrin binding protein loaded with beta-cyclodextrin. | Protein function is often regulated by conformational changes that occur in response to ligand binding or covalent modification such as phosphorylation. In many multidomain proteins these conformational changes involve reorientation of domains within the protein. Although X-ray crystallography can be used to determine ... |
10653890 | The intrinsic electrostatic potential and the intermediate ring of charge in the acetylcholine receptor channel. | A ring of aligned glutamate residues named the intermediate ring of charge surrounds the intracellular end of the acetylcholine receptor channel and dominates cation conduction (Imoto et al. 1988). Four of the five subunits in mouse-muscle acetylcholine receptor contribute a glutamate to the ring. These glutamates were... |
10654942 | A recurrent RNA-binding domain is appended to eukaryotic aminoacyl-tRNA synthetases. | Aminoacyl-tRNA synthetases of higher eukaryotes possess polypeptide extensions in contrast to their prokaryotic counterparts. These extra domains of poorly understood function are believed to be involved in protein-protein or protein-RNA interactions. Here we showed by gel retardation and filter binding experiments tha... |
10654930 | Crystal structure of a fibrillarin homologue from Methanococcus jannaschii, a hyperthermophile, at 1.6 A resolution. | Fibrillarin is a phylogenetically conserved protein essential for efficient processing of pre-rRNA through its association with a class of small nucleolar RNAs during ribosomal biogenesis. The protein is the antigen for the autoimmune disease scleroderma. Here we report the crystal structure of the fibrillarin homologu... |
10653814 | Solvent effects on the conformation of the transmembrane peptide gramicidin A: insights from electrospray ionization mass spectrometry. | The binding of sodium ions to the transmembrane channel peptide gramicidin A has permitted the use of electrospray ionization mass spectrometry to study its conformation in different solvent environments. The mass spectra of the peptide in the various solvents suggest that different conformations of gramicidin A differ... |
10651801 | The three transglycosylation reactions catalyzed by cyclodextrin glycosyltransferase from Bacillus circulans (strain 251) proceed via different kinetic mechanisms. | Cyclodextrin glycosyltransferase (CGTase) catalyzes three transglycosylation reactions via a double displacement mechanism involving a covalent enzyme-intermediate complex (substituted-enzyme intermediate). Characterization of the three transglycosylation reactions, however, revealed that they differ in their kinetic m... |
10648594 | Kinetics of ribosomal pausing during programmed -1 translational frameshifting. | In the Saccharomyces cerevisiae double-stranded RNA virus, programmed -1 ribosomal frameshifting is responsible for translation of the second open reading frame of the essential viral RNA. A typical slippery site and downstream pseudoknot are necessary for this frameshifting event, and previous work has demonstrated th... |
10648728 | Chronic administration of the triazolobenzodiazepine alprazolam produces opposite effects on corticotropin-releasing factor and urocortin neuronal systems. | In view of the substantial preclinical evidence that supports a seminal role of central corticotropin-releasing factor (CRF) neuronal systems in the physiology and pathophysiology of stress and anxiety, it is reasonable to suggest that the anxiolytic properties of benzodiazepines are mediated, at least in part, via reg... |
10642535 | Direct and reversed amino acid sequence pattern analysis: structural reasons for activity of reversed sequence sites and results of kinase site mutagenesis. | During studies of kinase phosphorylation, not all functional kinase phosphorylation may be found using consensus sequence patterns. This type of phosphorylation is termed 'non-consensus' or 'cryptic' phosphorylation. Results presented here based on molecular dynamics of short peptides show that protein kinases may phos... |
10642531 | Differential recognition of snake venom proteins expressing specific Arg-Gly-Asp (RGD) sequence motifs by wild-type and variant integrin alphaIIbbeta3: further evidence for distinct sites of RGD ligand recognition exhibiting negative allostery. | Several studies have demonstrated that the amino acid residues flanking the Arg-Gly-Asp (RGD) sequence of high-affinity ligands modulate their specificity of interaction with integrin complexes. Because of the absence of structural data for integrin complexes with bound ligand, the molecular basis for this specificity ... |
10642529 | Mechanistic studies of morphine dehydrogenase and stabilization against covalent inactivation. | Morphine dehydrogenase (MDH) of Pseudomonas putida M10 catalyses the NADP(+)-dependent oxidation of morphine and codeine to morphinone and codeinone. This enzyme forms the basis of a sensitive detection and assay method for heroin metabolites and a biotransformation process for production of hydromorphone and hydrocodo... |
10642498 | Preliminary evidence for the existence of specific functional assemblies between enzymes of the beta-oxidation pathway and the respiratory chain. | The electron-transferring flavoprotein (ETF) has been detected in two large soluble-protein complexes partially purified from sonicated porcine liver mitochondria. Size-exclusion chromatography and sucrose-density ultracentrifugation suggested molecular masses in the region of 390 to 420 kDa for the two complexes. Acti... |
10644372 | Mutation of predicted virion pit residues alters binding of Theiler's murine encephalomyelitis virus to BHK-21 cells. | Theiler's murine encephalomyelitis virus (TMEV), a natural pathogen of mice, is a member of the genus Cardiovirus in the family Picornaviridae. Structural studies indicate that the cardiovirus pit, a deep depression on the surface of the virion, is involved in receptor attachment; however, this notion has never been sy... |
10644355 | Properties of the naturally occurring soluble surface glycoprotein of ecotropic murine leukemia virus: binding specificity and possible conformational change after binding to receptor. | Ecotropic murine leukemia virus (MuLV) infection is initiated by the interaction between the surface glycoprotein (SU) of the virus and its cell-surface receptor mCAT-1. We investigated the SU-receptor interaction by using a naturally occurring soluble SU which was encoded by the envelope (env) gene of a defective endo... |
10642576 | Cholesterol efflux promotes acrosome reaction in goat spermatozoa. | Cholesterol efflux and membrane destabilization play an important role in sperm capacitation and membrane fusion in the acrosome reaction (AR). In this study we establish the effect of cholesterol removal from spermatozoa on acrosomal responsiveness. Mature goat spermatozoa were incubated in BSA-free medium in the pres... |
10646937 | A study of the correlation between organic matrices and nanocomposite materials in oyster shell formation. | Calcium carbonate minerals are an integral part of many organisms. These biogenic minerals are all of original size, shape and high strength, and they are quite different from those found in their abiotic precipitates. It has been accepted that the formation, morphological development and crystallography of the biocomp... |
10640738 | Non-CD28 costimulatory molecules present in T cell rafts induce T cell costimulation by enhancing the association of TCR with rafts. | While CD28 functions as the major T cell costimulatory receptor, a number of other T cell molecules have also been described to induce T cell costimulation. Here, we investigated the mechanisms by which costimulatory molecules other than CD28 contribute to T cell activation. Non-CD28 costimulatory molecules such as CD5... |
10639463 | Identification of immunodominant antigens from Helicobacter pylori and evaluation of their reactivities with sera from patients with different gastroduodenal pathologies. | Colonization of the gastric mucosa by Helicobacter pylori is the major cause of gastroduodenal pathologies in humans. Studying the outcome of the humoral immune response directed against this gastric pathogen may contribute substantially to vaccine development and to the improvement of diagnostic techniques based on se... |
10639441 | The cytotoxic T-lymphocyte epitope of the Plasmodium falciparum circumsporozoite protein also modulates the efficiency of receptor-ligand interaction with hepatocytes. | Malaria sporozoites are transmitted from the mosquito salivary gland to host hepatocytes within minutes of an infectious bite. The circumsporozoite protein (CS), which covers the surface of Plasmodium sporozoites, functions during these minutes in the targeting of host liver cells. The protein's potentially important r... |
10639376 | Efficacy of the cyclodextrin liquid preparation of itraconazole in treatment of denture stomatitis: comparison with itraconazole capsules. | This study investigated the efficacy of a cyclodextrin solution of itraconazole in the treatment of Candida-associated denture stomatitis. It was found that the liquid and capsule preparations of itraconazole were equally effective adjuncts in the treatment of this condition. However, the side effect profile indicates ... |
10639355 | Substitutions in the eyelet region disrupt cefepime diffusion through the Escherichia coli OmpF channel. | The Escherichia coli OmpF porin is a nonspecific channel involved in the membrane translocation of small hydrophilic molecules and especially in the passage of beta-lactam antibiotics. In order to understand the dynamic of charged-compound uptake through bacterial porins, specific charges located in the E. coli OmpF ch... |
10637364 | Propofol in anesthesia. Mechanism of action, structure-activity relationships, and drug delivery. | Propofol (2,6-diisopropylphenol) is becoming the intravenous anesthetic of choice for ambulatory surgery in outpatients. It is extensively metabolized, with most of the administered dose appearing in the urine as glucuronide conjugates. Favorable operating conditions and rapid recovery are claimed as the main advantage... |
10637336 | Characterization of Drosophila OVO protein DNA binding specificity using random DNA oligomer selection suggests zinc finger degeneration. | The Drosophila melanogaster ovo locus codes for several tissue- and stage-specific proteins that all possess a common C-terminal array of four C(2)H(2)zinc fingers. Three fingers conform to the motif framework and are evolutionarily conserved; the fourth diverges considerably. The ovo genetic function affects germ cell... |
10637415 | Solid phase synthesis and biological evaluation of enantiomerically pure wasp toxin analogues PhTX-343 and PhTX-12. | PhTX-343 and PhTX-12, analogues of the natural polyamine wasp toxin PhTX-433, were synthesised in 40-60% yields as pure enantiomers using solid phase synthesis techniques. Capillary electrophoresis procedures were developed for chiral separation and determination of enantiomeric purity (ee) of the enantiomers of PhTX-3... |
10637413 | Regioselective template synthesis, X-ray structure, and chiroptical properties of a topologically chiral sulfonamide catenane. | The synthesis of a topologically chiral in,out-bis-sulfonamide catenane and its "dimer" are reported. The structures of the amide wheel and of the catenane were resolved by X-ray analysis. NMR-titration of the monosulfonamide-wheel yielded conclusive association constants supporting the proposed regioselective mechanis... |
10633124 | Sequence variations within PrfA DNA binding sites and effects on Listeria monocytogenes virulence gene expression. | Reporter gene fusions were used to investigate the contributions of PrfA DNA binding sites to Listeria monocytogenes virulence gene expression. Our results suggest that the DNA sequence of PrfA binding sites determines the levels of expression of certain virulence genes, such as hly and mpl. Other virulence genes, such... |
10633109 | Two regions of EpsL involved in species-specific protein-protein interactions with EpsE and EpsM of the general secretion pathway in Vibrio cholerae. | Extracellular secretion of proteins via the type II or general secretion pathway in gram-negative bacteria requires the assistance of at least 12 gene products that are thought to form a complex apparatus through which secreted proteins are translocated. Although this apparatus is specifically required only for the out... |
10633101 | Bacteriophage T4 self-assembly: localization of gp3 and its role in determining tail length. | Gene 3 of bacteriophage T4 participates at a late stage in the T4 tail assembly pathway, but the hypothetical protein product, gp3, has never been identified in extracts of infected cells or in any tail assembly intermediate. In order to overcome this difficulty, we expressed gp3 in a high-efficiency plasmid expression... |
10633100 | Bacteriophage T4 self-assembly: in vitro reconstitution of recombinant gp2 into infectious phage. | T4 gene 2 mutants have a pleiotropic phenotype: degradation of injected phage DNA by exonuclease V (ExoV) in the recBCD(+) host cell cytoplasm and a low burst size due, at least in part, to a decreased ability for head-to-tail (H-T) joining. The more N terminal the mutation, the more pronounced is the H-T joining defec... |
10627544 | Two widely spaced initiator binding sites create an HMG1-dependent parvovirus rolling-hairpin replication origin. | Minute virus of mice (MVM) replicates via a linearized form of rolling-circle replication in which the viral nickase, NS1, initiates DNA synthesis by introducing a site-specific nick into either of two distinct origin sequences. In vitro nicking and replication assays with substrates that had deletions or mutations wer... |
10627522 | Possible involvement of the double-stranded RNA-binding core protein sigmaA in the resistance of avian reovirus to interferon. | Treatment of primary cultures of chicken embryo fibroblasts with a recombinant chicken alpha/beta interferon (rcIFN) induces an antiviral state that causes a strong inhibition of vaccinia virus and vesicular stomatitis virus replication but has no effect on avian reovirus S1133 replication. The fact that avian reovirus... |
30473624 | Antiangiogenic Gene Therapy in Cancer. | One of the most recent and exciting approaches in cancer gene therapy is the ability to target the developing blood supply of the tumor. An appealing feature of antiangiogenic gene therapy is that the tumor vasculature is a readily accessible target, particularly when the carrier and its gene are administered systemica... |
22607443 | Stabilization of Double Stranded Homologous Poly(dA)·Poly(dT) by Taxol. | Abstract The nucleic acid activity of taxol and paclitaxel was investigated with synthetic and natural oligo- and polynucleotides. The polynucleotides poly(dA)·poly(dT), poly(dG)·poly(dC), poly [d(A-T)]·poly[d(A-T)], poly[d(G-C)]·poly[d(G-C)] and calf thymus DNA were used. The oligonucleotides are 24-mers with d(puri... |
22607433 | Algorithmic Self-Assembly of DNA: Theoretical Motivations and 2D Assembly Experiments. | Abstract Biology makes things far smaller and more complex than anything produced by human engineering. The biotechnology revolution has for the first time given us the tools necessary to consider engineering on the molecular level. Research in DNA computation, launched by Len Adleman, has opened the door for experim... |
22607428 | An earring for the double helix: assembly of topological links comprising duplex DNA and a circular oligodeoxynucleotide. | Abstract Novel DNA nanostructures, locked pseudorotaxane and locked catenane were assembled through topological linkage of a double-stranded target to a circular oligodeoxyribonucleotide (cODN)(+). The formation of these supramolecular complexes occurs with remarkable sequence specificity and is accomplished via loca... |
22607411 | Modeling molecular recognition: theory and application. | Abstract Efficient, reliable methods for calculating the binding affinities of noncovalent complexes would allow advances in a variety of areas such as drug discovery and separation science. We have recently described a method that accommodates significant physical detail while remaining fast enough for use in molecu... |
21432480 | Policy functions of smoking control in Japan. | Analysis of policy functions, with a focus on their major participants, elicits a clear picture of the decision-making process for smoking control in Japan. Activities of various advocacy groups have affected the functions of policy, including: Intelligence, Promotion, Prescription, Invocation, Application and Appraisa... |
20681124 | Effect of cholesterol on the motility and plasma membrane integrity of frozen equine spermatozoa after thawing. | The aim of the present study was to investigate the cryoprotectant properties of cholesterol after incorporation into the plasma membranes of equine spermatozoa. A cholesterol-methyl-beta-cyclodextrin complex was used to alter sperm plasma membrane cholesterol content. Ejaculates from six stallions were centrifuged in ... |
19401746 | Two-photon holography in a 3D photopolymer host-guest matrix. | We demonstrate for the first time two-photon induced holographic recording at an arbitrary point in three dimensional photopolymeric cube by overlapping two coherent pulses from a 200 femtosecond Ti: Sapphire tunable laser operating at 710 nm. Spatial overlap is achieved by a novel pupil division method. The polymer ma... |
19096725 | The Genetic Basis of HIV-1 Resistance to Reverse Transcriptase and Protease Inhibitors. | HIV-1 drug resistance is caused by mutations in the reverse transcriptase (RT) and protease enzymes, the molecular targets of antiretroviral therapy. At the beginning of the year 2000, two expert panels recommended that HIV-1 RT and protease susceptibility testing be used to help select antiretroviral drugs for HIV-1-i... |
18475947 | Toxicity, Spectroscopic Characterization and Electrochemical Behaviour of New Macrocclic Complexes of Lead(II) and Palladium(II) Metals. | Tetraazamacrocyclie complexes of lead and palladium have been synthesized by the template process using the bis(benzil)ethylenediamine precursor. The tetradentate macrocycle (maL) reacts with PbCl(2), PdCl(2) and different diamines in a 1:1:1 molar ratio in methanol to give several solid complexes of the types [Pb(maL)... |
16232729 | Alteration of product specificity of cyclodextrin glucanotransferase from Thermococcus sp. B1001 by site-directed mutagenesis. | Cyclodextrin glucanotransferase (CGTase) from the hyperthermophilic archaeon Thermococcus sp. B1001 catalyzed the production predominantly of alpha-cyclodextrin (CD) from starch (Tachibana, Y. et al., Appl. Environ. Microbiol., 65, 1991-1997, 1999). The CGTase gene (cgtA) from this strain was cloned and sequenced. It w... |
16228417 | (18)O and mass spectrometry in chlorophyll research: Derivation and loss of oxygen atoms at the periphery of the chlorophyll macrocycle during biosynthesis, degradation and adaptation. | Chlorophylls, magnesium-containing tetrapyrrolic pigments of photosynthesis, are widely-distributed in Nature and participate in both light harvesting and in the transduction of light energy to chemical energy for the photosynthetic fixation of carbon dioxide. We briefly discuss the extensive role of various isotopic l... |
16228483 | Electric properties of thylakoid membranes from pea mutants with modified carotenoid and chlorophyll-protein complex composition. | Surface electric properties of thylakoid membranes from wild type and two mutant forms, Coeruleovireus 2/16 and Costata 2/133, of pea are investigated by electric light scattering and microelectrophoretic measurements. Characterization of the chlorophyll-protein complexes in thylakoid membranes reveals that the relativ... |
16228437 | The primary electron acceptor of green sulfur bacteria, bacteriochlorophyll 663, is chlorophyll a esterified with Delta2,6-phytadienol. | The primary electron acceptor of green sulfur bacteria, bacteriochlorophyll (BChl) 663, was isolated at high purity by an improved purification procedure from a crude reaction center complex, and the molecular structure was determined by fast atom bombardment mass spectroscopy (FAB-mass), (1)H- and (13)C-NMR spectromet... |
10932106 | Supramolecular photochemistry and solar cells | Supramolecular photochemistry as well as solar cells are fascinating topics of current interest in Inorganic Photochemistry and very active research fields which have attracted wide attention in last two decades. A brief outline of the investigations in these fields carried out in our Laboratory of Inorganic Photochemi... |
10932103 | Intercalation compounds involving inorganic layered structures | Two-dimensional inorganic networks can shown intracrystalline reactivity, i.e., simple ions, large species as Keggin ions, organic species, coordination compounds or organometallics can be incorporated in the interlayer region. The host-guest interaction usually causes changes in their chemical, catalytic, electronic a... |
10932101 | Supramolecular effects in dendritic systems containing photoactive groups | In this article are described dendritic structures containing photoactive groups at the surface or in the core. The observed supramolecular effects can be attributed to the nature of the photoactive group and their location in the dendritic architecture. The peripheric azobenzene groups in these dendrimeric compounds c... |
10932099 | Supramolecular chemistry and technology | Supramolecular chemistry deals with the association of several chemical species, in an organized way and according to well defined purposes. Based on a molecular engineering approach, supramolecular structures can be designed from pre-formed building blocks, providing a promising route from chemistry to molecular nanot... |
10813940 | Synthesis of thiamacrocycles and conformational studies on their precursors | 1-(4-Nitrophenyl)-7-phenylthioheptane (1) and -9-phenylthiononane (2) have been synthesized and their conformations studied in solution and in the solid state. MMX calculations suggest that the global energy minimum structures are bent in the gas phase, probably owing to edge-to-face intramolecular attractive interacti... |
10747388 | A new organic nanoporous architecture: dumb-bell-shaped molecules with guests in parallel channels | A new type of dumb-bell-shaped host molecule (6-8) has been synthesised, of which 1,8-bis((1)-adamantyl)-1,3,5,7-octatetrayne (8 = BAOT) forms an open porous architecture when cocrystallised with a number of typical solvent molecules. Adamantyl substituents attached to a tetraalkyne spacer build up the walls of paralle... |
10747384 | Templates, "wheeled reagents", and a new route to rotaxanes by anion complexation: the trapping method | The topological aspects of rotaxanes are compared with those of the other families of mechanically interlocked molecules: catenanes and molecular knots. The role of the different types of templates in the well-known threading and clipping procedures often used for rotaxane synthesis are discussed. Finally the conceptua... |
10654791 | Elution characteristics of natural cyclodextrins on porous graphitic carbon | The retention behavior of natural alpha-, beta-, and gamma-cyclodextrins on a porous graphitic carbon (PGC) stationary phase is investigated. Unusual retention properties for reversed-phase chromatographic conditions are observed with acetonitrile-methanol and water-methanol mixtures as mobile phases. It is assumed tha... |
10649420 | Molecular Dispersion of Chains in the Mixed-Valence Complexes | A way to prepare molecular electronic wires in organic media is the solubilization of one-dimensional mixed-valence complexes with varied metal species through the formation of amphiphilic supramolecular assemblies (see picture). Dissociation and reassembly of the complex was detected as thermochromism in the intervale... |
10649405 | Reducing Molecular Shuttling to a Single Dimension. | An analogy with a cart on a roller coaster partially explains the shuttling motion of macrocycles in peptide rotaxanes. Just above the barrier to shuttling, the macrocycle statistically populates the "track" rather than the low-energy "stations" (see the potential energy curve). The dynamics of the movement is describe... |
10649404 | 5-(beta-Cyclodextrinylamino)-5-Deoxy-alpha-D-Riboses as Models for Nuclease, Ligase, Phosphatase, and Phosphorylase. | beta-Cyclodextrin derivatives crowned with ribose rings (such as 1) catalyzed the hydrolysis, esterification, and phosphorylation of catechol-derived phosphate esters. The vicinal cis-diols on the ribose groups appear to play a major role in the catalytic activity of these enzyme models by the formation of hydrogen bon... |
10649386 | Encoded Helical Self-Organization and Self-Assembly into Helical Fibers of an Oligoheterocyclic Pyridine - Pyridazine Molecular Strand. | The conformational information of an oligoheterocyclic strand containing a repeating pyridine - pyridazine codon self-organizes into a helical molecular unit, which subsequently self-assembles into helical fibers and macrofibers in dichloromethane and pyridine. The spontaneous formation of helical structures is based o... |
10649375 | Investigations of Thin Films with Amphiphilic Dendrimers Bearing Peripheral Fullerene Subunits. | In spite of a molecular mass of 7704.6 g mol(-1), third-generation compound G3 (shown schematically; Z=C(8)H(17)) is able to form stable Langmuir films. In a systematic study, the amphiphilic properties of the corresponding dendrimers of first (G1) and second generation (G2), with one and two peripheral fullerene units... |
10649372 | Bis-Capsules: Cooperative Reversible Encapsulation of Two Molecules in Adjacent Separate Chambers. | Unprecedented communication takes place between guests G that are reversibly encapsulated in adjacent, but physically separate, chambers of a side-to-side bis-capsule (shown schematically). This was shown by neighbor-dependent NMR chemical shifts of the identical or nonidentical guest molecules. Furthermore, no 1:1 hos... |
10649366 | The "Dendritic Effect" in Homogeneous Catalysis with Carbosilane-Supported Arylnickel(II) Catalysts: Observation of Active-Site Proximity Effects in Atom-Transfer Radical Addition. | Advantages of homo- and heterogeneous catalysts are united in metallodendritic molecules where nickel-based catalysts are bound to carbosilane dendrimers. The first direct indication of a "dendritic effect" in the redox catalysis behavior is described: variation of the dendrimer support controls the proximity of the Ni... |
10649357 | A Self-Complexing | A supramolecular homodimer is formed in solution and in the solid state by a self-complementary [2]catenane incorporating a 1,5-dioxynaphthalene-based macrocyclic polyether interlocked with a bipyridinium-based tetracationic cyclophane (shown schematically). This unique example of self-recognition is the result of a co... |
10649355 | Thermoregulated Optical Properties of Peptidic Pseudorotaxanes. | Natural peptide spine and artificial crown ether are blended together to form a hybrid structure. A dicationic benzylammonium guest threads through the crown ether pendants and the resulting noncovalent, self-assembled pseudorotaxane complex, shown schematically in the picture, is both stable and has optical properties... |
10649353 | Resorcarene-Based Nanoarchitectures: Metal-Directed Assembly of a Molecular Loop and Tetrahedron. | Large cavities and portals are present in the nanoscale molecular architectures formed from dithiocarbamate-functionalized resorcarene ligands and zinc(II) or copper(III) ions. With Zn(II) a molecular loop based on a triangle of resorcarene cups is prepared-the cavity is circular (shown on the left). A molecular cage b... |
10646597 | Nanoscopic channel lattices with controlled anisotropic wetting | Engineered microscopic surface structures allow local control of physical surface properties such as adhesion, friction and wettability. These properties are related both to molecular interactions and the surface topology--for example, selective adsorption and molecular recognition capabilities require controlled aniso... |
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