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12802397 | Antimutagenic and antioxidant activities of crown compounds in comparison with the effects of garlic extract. | Antimutagenic activity of N-carboxyalkyl derivatives of aza- and benzoazacrown compounds was revealed and antimutagenic activity of garlic extract was confirmed. Specific genoprotective effect of crown compounds towards the effects of various mutagens was demonstrated. The antimutagenic effect of these compounds was no... |
12799065 | The acid phosphatase positive organelles of the Giardia lamblia trophozoite contain a membrane bound cathepsin C activity. | We found a dipeptidyl aminopeptidase activity in the parasitic protozoan Giardia lamblia with properties similar to the lysosomal cathepsin C of rat-liver lysosomes. Subcellular fractionation of this parasite indicated that the cathepsin C activity is located in organelles not distinguishable from the ones containing a... |
12761167 | Biochemical and genetic analyses of a novel gamma-cyclodextrin glucanotransferase from an alkalophilic Bacillus clarkii 7364. | On screening for microorganisms in soil obtained in Japan that produce large amounts of gamma-cyclodextrin (gamma-CD), we identified a novel alkalophilic bacterium, Bacillus clarkii 7364. The cyclodextrin glucanotransferase (CGTase) secreted into the culture medium by this bacterium was purified by affinity chromatogra... |
12700943 | Antibody therapy of non-Hodgkin's B-cell lymphoma. | Engineering antibodies with reduced immunogenicity and enhanced effector functions, and selecting antigen targets with the appropriate specificity, density, and/or functionality, have contributed to the recent clinical successes in using unconjugated "naked" antibody therapies of B-cell lymphoma (rituximab) and breast ... |
12611902 | Regulation of the SHP-2 tyrosine phosphatase by a novel cholesterol- and cell confluence-dependent mechanism. | Endothelial cells approaching confluence exhibit marked decreases in tyrosine phosphorylation of receptor tyrosine kinases and adherens junctions proteins, required for cell cycle arrest and adherens junctions stability. Recently, we demonstrated a close correlation in endothelial cells between membrane cholesterol and... |
12610209 | A rhodium(III) complex for high-affinity DNA base-pair mismatch recognition. | A rhodium(III) complex, rac-[Rh(bpy)(2)phzi](3+) (bpy, 2,2'-bipyridine; phzi, benzo[a]phenazine-5,6-quinone diimine) has been designed as a sterically demanding intercalator targeted to destabilized mismatched sites in double-helical DNA. The complex is readily synthesized by condensation of the phenazine quinone with ... |
12669249 | A phase 2 study of the cytotoxic immunoconjugate CMB-401 (hCTM01-calicheamicin) in patients with platinum-sensitive recurrent epithelial ovarian carcinoma. | The compound CMB-401 is an immunoconjugate consisting of the monoclonal antibody (MAb) hCTM01 directed against polymorphic epithelial mucin covalently bound to the cytotoxic antibiotic calicheamicin by an amide linker. We evaluated CMB-401 as monotherapy for the treatment of recurrent platinum-sensitive epithelial ovar... |
12604782 | Colocalization and nonrandom distribution of Kv1.3 potassium channels and CD3 molecules in the plasma membrane of human T lymphocytes. | Distribution and lateral organization of Kv1.3 potassium channels and CD3 molecules were studied by using electron microscopy, confocal laser scanning microscopy, and fluorescence resonance energy transfer. Immunogold labeling and electron microscopy showed that the distribution of FLAG epitope-tagged Kv1.3 channels (K... |
12604590 | A role of topoisomerase II in linking DNA replication to chromosome condensation. | The condensin complex and topoisomerase II (topo II) have different biochemical activities in vitro, and both are required for mitotic chromosome condensation. We have used Xenopus egg extracts to investigate the functional interplay between condensin and topo II in chromosome condensation. When unreplicated chromatin ... |
12601166 | Quantitative proteomic analysis indicates increased synthesis of a quinolone by Pseudomonas aeruginosa isolates from cystic fibrosis airways. | The opportunistic bacterial pathogen Pseudomonas aeruginosa colonizes airways of individuals with cystic fibrosis (CF) with resultant chronic destructive lung disease. P. aeruginosa adaptation to the CF airway includes biofilm formation and antibiotic resistance. Isolates from asymptomatic individuals in the first 3 ye... |
12601148 | DNA molecule provides a computing machine with both data and fuel. | The unique properties of DNA make it a fundamental building block in the fields of supramolecular chemistry, nanotechnology, nano-circuits, molecular switches, molecular devices, and molecular computing. In our recently introduced autonomous molecular automaton, DNA molecules serve as input, output, and software, and t... |
12598659 | Non-heme iron enzymes: contrasts to heme catalysis. | Non-heme iron enzymes catalyze a wide range of O(2) reactions, paralleling those of heme systems. Non-heme iron active sites are, however, much more difficult to study because they do not exhibit the intense spectral features characteristic of the porphyrin ligand. A spectroscopic methodology was developed that provide... |
12598654 | Crystal structure of the retinoblastoma tumor suppressor protein bound to E2F and the molecular basis of its regulation. | The retinoblastoma tumor suppressor protein (pRb) regulates the cell cycle, facilitates differentiation, and restrains apoptosis. Furthermore, dysfunctional pRb is thought to be involved in the development of most human malignancies. Many of the functions of pRb are mediated by its regulation of the E2F transcription f... |
12594203 | Synergy of silent and hot spot mutations in importin beta reveals a dynamic mechanism for recognition of a nuclear localization signal. | Molecular recognition of the importin beta-binding (IBB) domain of importin alpha by importin beta is critical for the nuclear import of protein cargoes containing a classical nuclear localization signal. We have studied the function of four conserved tryptophans of importin beta (Trp-342, Trp-430, Trp-472, and Trp-864... |
12594172 | Transport of plasma membrane-derived cholesterol and the function of Niemann-Pick C1 Protein. | To visualize the intracellular transport of plasma membrane-derived cholesterol under physiological and pathophysiological conditions, a novel fluorescent cholesterol analog, 6-dansyl cholestanol (DChol), has been synthesized. We present several lines of evidence that DChol mimics cholesterol. The cholesterol probe cou... |
12594333 | An affibody in complex with a target protein: structure and coupled folding. | Combinatorial protein engineering provides powerful means for functional selection of novel binding proteins. One class of engineered binding proteins, denoted affibodies, is based on the three-helix scaffold of the Z domain derived from staphylococcal protein A. The Z(SPA-1) affibody has been selected from a phage-dis... |
12591922 | The transport of low density lipoprotein-derived cholesterol to the plasma membrane is defective in NPC1 cells. | Niemann-Pick disease type C (NPC) is characterized by lysosomal storage of cholesterol and gangliosides, which results from defects in intracellular lipid trafficking. Most studies of NPC1 have focused on its role in intracellular cholesterol movement. Our hypothesis is that NPC1 facilitates the egress of cholesterol f... |
12591960 | Proteins with H-bond packing defects are highly interactive with lipid bilayers: Implications for amyloidogenesis. | We noticed that disease-related amyloidogenic proteins and especially cellular prion proteins have the highest proportion of incompletely desolvated backbone H bonds among soluble proteins. Such bonds are vulnerable to water attack and thus represent structural weaknesses. We have measured the adsorption of proteins on... |
12591949 | The integrity of a cholesterol-binding pocket in Niemann-Pick C2 protein is necessary to control lysosome cholesterol levels. | The neurodegenerative disease Niemann-Pick Type C2 (NPC2) results from mutations in the NPC2 (HE1) gene that cause abnormally high cholesterol accumulation in cells. We find that purified NPC2, a secreted soluble protein, binds cholesterol specifically with a much higher affinity (K(d) = 30-50 nM) than previously repor... |
12638047 | Separation of positional isomers by the use of coupled shape-selective stationary phase columns. | The successful separation of 2- and 3-methyl-substituted positional isomers of butanol, butyl acetate, and butanoic acid and its ethyl ester, is reported. These compounds are of interest in the study of wine flavour, however the separation of the 2- and 3-methyl isomers may present problems, and more so in the presence... |
12649743 | Induction of cellular immunity by anti-idiotypic antibodies mimicking GD2 ganglioside. | Gangliosides are potentially useful targets for tumor destruction by antibodies. However, the role of gangliosides in T cell-mediated immunity to tumors is unclear. We produced three murine monoclonal anti-idiotypic antibodies (Ab2) against a monoclonal antibody (Ab1) that binds strongly to melanoma-associated GD2 gang... |
12655396 | Effects of selective inactivation of individual genes for low-molecular-mass subunits on the assembly of photosystem II, as revealed by chloroplast transformation: the psbEFLJoperon in Nicotiana tabacum. | Photosystem (PSII) is a supramolecular polypeptide complex found in oxygenic photosynthetic membranes, which is capable of extracting electrons from water for the reduction of plastoquinone. An intriguing feature of this assembly is the fact that it includes more than a dozen low-mass polypeptides of generally unknown ... |
12576549 | Suberoylanilide hydroxamic acid, a histone deacetylase inhibitor, ameliorates motor deficits in a mouse model of Huntington's disease. | Huntington's disease (HD) is an inherited, progressive neurological disorder that is caused by a CAG/polyglutamine repeat expansion and for which there is no effective therapy. Recent evidence indicates that transcriptional dysregulation may contribute to the molecular pathogenesis of this disease. Supporting this view... |
12574521 | DNA duplex-quadruplex exchange as the basis for a nanomolecular machine. | There is currently great interest in the design of nanodevices that are capable of performing linear or rotary movements. Protein molecular machines are abundant in biology but it has recently been proposed that nucleic acids could also act as nanomolecular machines in model systems. Several types of movements have bee... |
12574504 | Nanodissection and high-resolution imaging of the Rhodopseudomonas viridis photosynthetic core complex in native membranes by AFM. Atomic force microscopy. | In photosynthesis, highly organized multiprotein assemblies convert sunlight into biochemical energy with high efficiency. A challenge in structural biology is to analyze such supramolecular complexes in native membranes. Atomic force microscopy (AFM) with high lateral resolution, high signal-to-noise ratio, and the po... |
12574502 | Repression of the HIV-1 5' LTR promoter and inhibition of HIV-1 replication by using engineered zinc-finger transcription factors. | Zinc finger domains are small DNA-binding modules that can be engineered to bind desired target sequences. Functional transcription factors can be made from these DNA-binding modules, by fusion with an appropriate effector domain. In this study, eight three-zinc-finger proteins (ZFPs) that bound HIV-1 sequences in vitr... |
12574501 | Inhibition of herpes simplex virus 1 gene expression by designer zinc-finger transcription factors. | The herpes simplex virus 1 (HSV-1) replicative cycle begins by binding of the viral activator, VP16, to a set of sequences in the immediate-early (IE) gene promoters. With the aim of inhibiting this cycle, we have constructed a number of synthetic zinc-finger DNA-binding peptides by using recently reported methods. Pep... |
12488511 | Efficient large-scale production and concentration of HIV-1-based lentiviral vectors for use in vivo. | The aim of this study was to develop an efficient method for packaging and concentrating lentiviral vectors that consistently yields high-titer virus on a scale suitable for in vivo applications. Transient cotransfection of 293T packaging cells with DNA plasmids encoding lentiviral vector components was optimized using... |
12566443 | A ligand-induced conformational change in apolipoprotein(a) enhances covalent Lp(a) formation. | Lipoprotein(a) (Lp(a)) assembly proceeds via a two-step mechanism in which initial non-covalent interactions between apolipoprotein(a) (apo(a)) and low density lipoprotein precede disulfide bond formation. In this study, we used analytical ultracentrifugation, differential scanning calorimetry, and intrinsic fluorescen... |
12563314 | Host defense against Pseudomonas aeruginosa requires ceramide-rich membrane rafts. | Pseudomonas aeruginosa infection is a serious complication in patients with cystic fibrosis and in immunocompromised individuals. Here we show that P. aeruginosa infection triggers activation of the acid sphingomyelinase and the release of ceramide in sphingolipid-rich rafts. Ceramide reorganizes these rafts into large... |
12566569 | Dynamic recruitment of dynamin for final mitochondrial severance in a primitive red alga. | Dynamins are a eukaryote-specific family of GTPases. Some family members are involved in diverse and varied cellular activities. Here, we report that the primitive red alga Cyanidioschyzon merolae retains only one dynamin homolog, CmDnm1, belonging to the mitochondrial division subfamily. Previously, the bacterial cell... |
12747579 | Effects of dietary beta-cyclodextrin in hypercholesterolaemic rats. | Beta-cyclodextrin is a compound that forms inclusion complexes with a variety of molecules, specially bile acids and sterols. This study examines the effects of beta-cyclodextrin on cholesterol and bile acid metabolism in hypercholesterolaemic rats. Male Wistar rats were divided into 4 groups that received during 7 wee... |
12562855 | Biotinylated theta-toxin derivative as a probe to examine intracellular cholesterol-rich domains in normal and Niemann-Pick type C1 cells. | BCtheta is a proteolytically nicked and biotinylated derivative of a cholesterol binding protein perfringolysin O (theta-toxin), and has been used to detect cholesterol-rich domains at the plasma membrane (PM). Here we show that by modifying the cell fixation condition, BCtheta can also be used to detect cholesterol-ri... |
12729014 | Release characteristics of flavor from spray-dried powder in boiling water and during rice cooking. | The release characteristics of flavor in boiling water and the flavor retention in the rice after cooking were investigated by using spray dried powder in encapsulated in or emulsified with d-limonene or ethyl n-hexanoate in cyclodextrin and maltodextrin, or in gum arabic and maltodextrin. The behavior of flavor releas... |
12728995 | Isolation of Paenibacillus illinoisensis that produces cyclodextrin glucanotransferase resistant to organic solvents. | A bacterium that secreted cyclodextrin glucanotransferase (CGTase) in a medium overlaid with n-hexane was isolated and identified as Paenibacillus illinoisensis strain ST-12 K. The CGTase of the strain was purified from the culture supernatant. The molecular mass was 70 kDa. The enzyme was stable at pH 6 to 10 and acti... |
12697168 | Stereo- and regiospecificity of yeast phytases-chemical synthesis and enzymatic conversion of the substrate analogues neo- and L-chiro-inositol hexakisphosphate. | Phytases are enzymes that catalyze the hydrolysis of phosphate esters in myo-inositol hexakisphosphate (phytic acid). The precise routes of enzymatic dephosphorylation by phytases of the yeast strains Saccharomyces cerevisiae and Pichia rhodanensis have been investigated up to the myo-inositol trisphosphate level, incl... |
12697166 | Selective binding of chiral molecules of cinchona alkaloid by beta- and gamma-cyclodextrins and organoselenium-bridged bis(beta-cyclodextrin)s. | The inclusion complexation behavior of chiral members of cinchona alkaloid with beta- and gamma-cyclodextrins (1 and 2) and 6,6(')-trimethylenediseleno-bridged bis(beta-cyclodextrin) (3) was assessed by means of fluorescence and 2D-NMR spectroscopy. The spectrofluorometric titrations have been performed in aqueous buff... |
12693815 | Functional stabilization of trypsin by conjugation with beta-cyclodextrin-modified carboxymethylcellulose. | Bovine pancreatic trypsin was chemically modified by a beta-cyclodextrin-carboxymethylcellulose polymer using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide as coupling agent. The conjugate retained 110% and 95% of the initial esterolytic and proteolytic activity, respectively, and contained about 2 mol of polymer per ... |
12680592 | Pharmacological characterization of mammalian D1 and D2 dopamine receptors expressed in Drosophila Schneider-2 cells. | Mammalian D1 and D2 dopamine receptors were stably expressed in Drosophila Schneider-2 (S2) cells and screened for their pharmacological properties. Saturable, dose-dependent, high affinity binding of the D1-selective antagonist [3H]SCH-23390 was detected only in membranes from S2 cells induced to express rat dopamine ... |
12678493 | Cyanovirin-N: a sugar-binding antiviral protein with a new twist. | Cyanovirin-N (CV-N), an 11-kDa protein from the cyanobacterium Nostoc ellipsosporum, is a highly potent virucidal agent that has generated interest as a lead natural product for the prevention and chemotherapy of human immunodeficiency virus infection. The antiviral activity of CV-N is mediated through specific, high-a... |
12678488 | Evolutionary and functional implications of the complex glycosylation of Skp1, a cytoplasmic/nuclear glycoprotein associated with polyubiquitination. | Protein degradation is regulatory for the cell cycle, signal transduction and gene transcription. A critical step is the selective marking of the target protein, resulting in polyubiquitination by one of a large number of E3-ubiquitin ligases. Both target marking and E3-ubiquitin ligase activity are associated with com... |
12664979 | Degradation of supramolecular complexes photoinduced by iron(III): the influence of the host on the reactivity of the guest. | Fe(III)-photoinduced degradation of two different supramolecular host-guest complexes, naphthalene with alpha-cyclodextrin and 4-chloroaniline with p-sulfonic-calix[4]arene; was studied in aqueous solution. The stoichiometries, equilibrium constants and conformations of these complexes were characterized. In both cases... |
12664965 | From metal complexes to fullerene arrays: exploring the exciting world of supramolecular photochemistry fifteen years after its birth. | After over 15 years of extensive research work in many laboratories worldwide, supramolecular photochemistry is a well-established and highly recognized branch of science. A brief retrospective view on the birth and infancy of this research area is given and some of the latest developments are discussed. In supramolecu... |
12648019 | Influence of hydroxypropyl beta-cyclodextrin on the corneal permeation of pilocarpine. | The influence of hydroxypropyl beta-cyclodextrin (HPbetaCD) on the corneal permeation of pilocarpine nitrate was investigated by an in vitro permeability study using isolated rabbit cornea. Pupillary-response pattern to pilocarpine nitrate with and without HPbetaCD was examined in rabbit eye. Corneal permeation of pilo... |
12648011 | Carbamazepine/betaCD/HPMC solid dispersions. II. Physical characterization. | Solid dispersions containing carbamazepine (CBZ) associated with beta-cyclodextrin (betaCD) and/or hydroxypropyl methylcellulose were prepared by two different methods, spray-drying or physical mixture, and characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), infrared (IR) spect... |
12648010 | Carbamazepine/betaCD/HPMC solid dispersions. I. Influence of the spray-drying process and betaCD/HPMC on the drug dissolution profile. | The aim of this study was to compare carbamazepine (CBZ) solid dispersions prepared by spray-drying of aqueous dispersions with the corresponding physical mixtures. The influence of the association of beta-cyclodextrin (betaCD) and hydroxypropyl methylcellulose (HPMC) on the CBZ dissolution profile of the preparations ... |
12647828 | Quantitation of the enantiomers of ofloxacin by capillary electrophoresis in the parts per billion concentration range for in vitro drug absorption studies. | Ofloxacin, a chiral fluoroquinolone, possesses two optical isomers. The antibacterial activity of S-(-)-ofloxacin is reported to be 8-128 times higher than that of R-(+)-ofloxacin. A capillary zone electrophoresis method has been developed to quantify the enantiomers of ofloxacin in high diluted samples (20-700 ng/ml f... |
12645944 | T cell costimulation by the hepatitis C virus envelope protein E2 binding to CD81 is mediated by Lck. | Binding of the hepatitis C virus (HCV) envelope protein E2 to CD81 provides a costimulatory signal for human T cells. This phenomenon may play a role in liver damage and autoimmune manifestations associated with HCV infection. Here we show that cross-linking of CD81 by HCV E2 induced a calcium flux in T cells that depe... |
12643586 | Determination of terbutaline enantiomers in human urine by capillary electrophoresis using hydroxypropyl-beta-cyclodextrin as a chiral selector. | A method for the determination of terbutaline enantiomers in human urine by capillary electrophoresis has been developed. Optimum resolution was achieved using 50 mM phosphate buffer, pH 2.5, containing 15 mM of hydroxypropyl-beta-cyclodextrin as a chiral selector. Urine samples were prepared by solid-phase extraction ... |
12641325 | Coupled column chromatography for separation and determination of enantiomers of phenylcarbamic acid derivatives in serum. | Columns packed with vancomycin coupled to an achiral C18 column and beta-cyclodextrin were used for the separation and the determination of enantiomers of alkoxysubstituted esters of phenylcarbamic acid in blood serum. The method involves off-line SPE, the separation of the racemate on a reversed-phase stationary phase... |
12638971 | Transformation of a C-methylcalix[4]resorcinarene-based host-guest complex from a wave-like to a novel triangular brick-wall architecture. | A novel 2D triangular brick-wall framework based on CMCR and bpe with included ruthenocene guest molecules is formed with time by conversion of a 1D wave-like polymer structure with an accompanying bowl-to-boat conformational change of the CMCR molecules. |
12638967 | A novel approach to polymeric hollow nanospheres with stabilized structure. | Polymeric hollow nanospheres with stabilized structure have been realized by self-assembly of crosslinkable rigid poly(amic acid) ester (PAE) oligomer and coil-like poly(4-vinylpyridine) (PVPy) via hydrogen bonding in their common solvent and subsequent photo-crosslinking of the PAE. |
12638951 | Redox-robust pentamethylamidoferrocenyl metallodendrimers that cleanly and selectively recognize the H2PO4- anion. | The first pentamethylferrocenyl (Fc*) dendrimers are synthesized from DSM polyamine dendrimers (generations 1 to 5) and cleanly and selectively recognize the H2PO4- anion. |
12636162 | Ligand-specific targeting of microspheres to phagocytes by surface modification with poly(L-lysine)-grafted poly(ethylene glycol) conjugate. | <h4>Purpose</h4>The purpose of this study was to demonstrate specific receptor-mediated targeting of phagocytes by functional surface coatings of microparticles, shielding from nonspecific phagocytosis and allowing ligand-specific interactions via molecular recognition.<h4>Methods</h4>Coatings of the comb polymer poly(... |
12631118 | Induction of DNA synthesis by ligation of the CD53 tetraspanin antigen in primary cultures of mesangial cells. | <h4>Background</h4>The interaction of mesangial cells with the extracellular matrix plays a major role in kidney biology. Tetraspanin proteins modulate cell interaction with the extracellular matrix. Tetraspanins form supramolecular structures on the cell membrane that send signals after engagement by unknown ligands, ... |
12631411 | Therapeutic equivalence of a low dose artemisinin formulation in falciparum malaria patients. | We have evaluated the therapeutic equivalence of a beta-cyclodextrin-artemisinin complex at an artemisinin dose of 150 mg, with a commercial reference preparation, Artemisinin 250 at a recommended dose of 250 mg. One hundred uncomplicated falciparum malarial patients were randomly assigned to orally receive either beta... |
12625553 | Assessment of the cross-reactivity and binding sites characterisation of a propazine-imprinted polymer using the Langmuir-Freundlich isotherm. | In this paper, the Langmuir-Freundlich isotherm is used to model the interaction of several triazines (desethylatrazine, desisopropylatrazine, simazine, atrazine, propazine and prometryn) with a propazine-imprinted polymer and to explain the observed cross-reactivity. Different rebinding experiments (each herbicide alo... |
12625552 | Ligand exchange chiral separations by cyclodextrin derivatives in capillary electrophoresis. | A beta-cyclodextrin substituted by an imidazole-bound histamine (CDmh) was successfully used to separate underivatised tryptophan racemate in capillary electrophoresis in the presence of copper(II) ion by the ligand exchange mechanism. To the best of our knowledge, this is the first example of a cyclodextrin derivative... |
12620810 | Four-gene-combination DNA vaccine protects mice against a lethal vaccinia virus challenge and elicits appropriate antibody responses in nonhuman primates. | Two major infectious forms of vaccinia virus (VACV) have been described: the intracellular mature virion (IMV), and the extracellular enveloped virion (EEV). Due to their stability in the environment, IMVs play a predominant role in host-to-host transmission, whereas EEVs play an important role in dissemination within ... |
12620618 | Cloning and expression of a putative cyclodextrin glucosyltransferase from the symbiotically competent cyanobacterium Nostoc sp. PCC 9229. | A polymerase chain reaction-based method was used to isolate a Nostoc sp. PCC 9229 cDNA from infected glands of Gunnera chilensis. The complete gene sequence was isolated from a genomic Nostoc sp. PCC 9229 library. Sequence analysis showed 84% amino acid similarity to a putative cyclodextrin glycosyltransferase from No... |
12618190 | Encapsulating streptomycin within a small 40-mer RNA. | We describe a 2.9 A X-ray structure of a complex between the aminocyclitol antibiotic streptomycin and an in vitro selected RNA aptamer, solved using the anomalous diffraction properties of Ba cations. The RNA aptamer, which contains two asymmetric internal loops, adopts a distinct cation-stabilized fold involving a se... |
12618188 | EF-Tu binding peptides identified, dissected, and affinity optimized by phage display. | The highly abundant GTP binding protein elongation factor Tu (EF-Tu) fulfills multiple roles in bacterial protein biosynthesis. Phage-displayed peptides with high affinity for EF-Tu were selected from a library of approximately 4.7 x 10(11) different peptides. The lack of sequence homology among the identified EF-Tu li... |
12615539 | The native-like conformation of Ure2p in fibrils assembled under physiologically relevant conditions switches to an amyloid-like conformation upon heat-treatment of the fibrils. | The [URE3] phenotype in the yeast Saccharomyces cerevisiae is inherited by a prion mechanism involving self-propagating Ure2p aggregates. It is believed that assembly of intact Ure2p into fibrillar polymers that bind Congo Red and show yellow-green birefringence upon staining and are resistant to proteolysis is the con... |
12615152 | The new HMQC-based technique for the quantitative determination of heteronuclear coupling constants. Application for the measurement of 3J(H'(i),P(i+1)) in DNA oligomers. | A new general J-HMQC-based technique is presented, which allows an accurate determination of heteronuclear coupling constants. The most important feature of this new approach includes acquisition of the two data sets with and without the additional pi(S)-pulse at the end of coupling evolution period. This enables prese... |
12613845 | Indirect capillary electrophoresis with 8-anilino-1-naphthalenesulfonic acid as a fluorescence probe for determining the apparent stability constant of an inclusion complex formed between a cyclodextrin and a solute. | An indirect capillary electrophoresis (CE) method was developed based on two competitive chemical equilibria for determining the stability constant of an inclusion complex formed between a cyclodextrin and a solute. 8-Anilino-1-naphthalenesulfonic acid was employed as a fluorescence probe. A linear relationship between... |
12613842 | Capillary electrophoretic separation of enantiomers in a high-pH background electrolyte by means of the single-isomer chiral resolving agent octa(6-O-sulfo)-gamma-cyclodextrin. | The new, alkali-stable, single-isomer, sulfated gamma-cyclodextrin, the sodium salt of octa(6-O-sulfo)-gamma-cyclodextrin (OS) was used for the first time to separate the enantiomers of non-ionic, acidic, basic and ampholytic analytes by capillary electrophoresis in high-pH aqueous background electrolytes. The effectiv... |
12613836 | Mechanistic study of enantiomeric recognition with native gamma-cyclodextrin by capillary electrophoresis, reversed-phase liquid chromatography, nuclear magnetic resonance spectroscopy, electrospray mass spectrometry and circular dichroism techniques. | The possible mechanisms for the chiral recognition of 2(S)-(3,5-bis-trifluoromethyl-phenyl)-2-[3(S)-(4-fluorophenyl)-4-(1H-[1,2,4]triazol-3-ylmethyl)-morpholin-2(R)-yloxy]-ethanol (compound A) and its enantiomer with native gamma-cyclodextrin (gamma-CD) were investigated using capillary electrophoresis (CE), reversed-p... |
12613802 | Preparation of a molecularly imprinted polymer for the solid-phase extraction of scopolamine with hyoscyamine as a dummy template molecule. | Molecularly imprinted polymers (MIPs) selective for scopolamine were produced using hyoscyamine (a close structural analogue) as template molecule. The produced polymers were used as media for solid-phase extraction, exhibiting selective binding properties for the analyte from biological samples. Human and calf urine a... |
12613649 | Acoustic wave sensor for barium based on poly[Ni(salen)(crown)] recognition chemistry. | Interfacial recognition of barium by a crown ether receptor is quantified using an acoustic wave sensor, and the isotherm characteristics rationalized in terms of solution complexation chemistry and polymer materials properties. |
12613644 | Novel supramolecular architectures in group 13 perfluoroaryl complexes. Synthesis and structures of [AlMe(C6F5)(mu-Me)]2 and GaMe(C6F5)2. | Novel supramolecular architectures are observed in the solid state structures of [AlMe(C6F5)(mu-Me)]2 (1) and Ga(C6F5)2Me (2) via pi-pi stacking between C6F5 rings and intermolecular aryl-F-->Ga interactions, respectively. |
12613640 | Fluorophore-capped cyclodextrins as efficient chemical-to-light energy converters. | Bisbenzimidazole-capped cyclodextrins, capable of forming supramolecules, harvest chemical energy from the oxidation reaction of a bis(aryl)oxalate and emit light two orders of magnitude more efficiently than fluorescein does. |
12613628 | Molecular recognition. Electrostatic effects in supramolecular self-assembly. | A di-positively charged metal-based receptor is shown to form 1:1 or 2:1 association complexes with rigid, linear two-site guests depending on the site separation, suggesting that electrostatic repulsion controls the association nuclearity. |
12613626 | Modulating the efficiency of Ru(II) luminescence via ion binding-induced conformational restriction of bipyridyl ligands. | Conformational restriction imposed upon Ru(bpy)32+ crown ether complexes by metal ion binding leads to enhanced luminescence. |
12613620 | 'Nucleo-nanocages': designed ternary oligodeoxyribonucleotides spontaneously form nanosized DNA cages. | DNA three-way junctions formed from three 30-mer oligonucleotides that contain single-chained self-complementary sticky ends spontaneously self-assemble into 'nucleo-nanocages': the exo- and endo-nuclease digestion experiments indicate that defects such as the single and double strand end structures are absent on the s... |
12613608 | Growth of individual hydrogen-bonded nanostructures on gold monolayers. | The growth of individual nanometer-sized (3.4 +/- 1.4 nm) hydrogen bonded assemblies 1(2) x (DEB)6 on gold monolayers was achieved through an exchange reaction between single isolated calix[4]arene dimelamine 2 (1.1 +/- 0.2 nm) embedded in hexanethiol monolayers and double rosette hydrogen bonded assembly 1(3) x (DEB)6... |
12613588 | Helical templating of polyiodide networks at a binuclear metallo complex. | A homobimetallic supramolecular helicate has been prepared from a new multimodal ligand, and used to template the formation of two polyiodide networks, one containing an unprecedented figure-of-eight polyiodide helix, the other dominated by peripheral C-H...I polyiodide chain interactions. |
12609735 | Translational machinery of channel catfish: II. Complementary DNA and expression of the complete set of 47 60S ribosomal proteins. | Ribosomal protein genes have become widely used as markers for phylogenetic studies and comparative genomics, but they have not been available in fish. We have cloned and sequenced a complete set of all 47 60S ribosomal protein cDNAs from channel catfish (Ictalurus punctatus), of which 43 included the complete protein ... |
12608748 | Hydrogen ion-selective poly(vinyl chloride) membrane electrode based on a calix[4]arene. | A hydrogen ion-selective poly(vinyl chloride) membrane electrode was constructed using 5,11,17,23-tetra-tert-butyl-25,26,27,28-tetracyanomethoxycalix[4]arene as a neutral carrier. The electrode showed an apparent Nernstian response in the 2-11.5 pH range with a slope of 54.0 +/- 0.2 mV/pH at 20 +/- degrees C. This elec... |
12606022 | Binding and retention of polycationic peptides and dendrimers in the vascular wall. | Extracellular matrix (ECM) of tissues, vascular tissue in particular, contains a high concentration of negatively charged glycosaminoglycans (GAGs), which are involved in the regulation of cell motility, cell proliferation and the regulation of enzyme activities. Previously, we have shown that the vascular ECM is capab... |
12598414 | Characterization of the anticonvulsant profile and enantioselective pharmacokinetics of the chiral valproylamide propylisopropyl acetamide in rodents. | 1. Propylisopropyl acetamide (PID) is a new chiral amide derivative of valproic acid. The purpose of this study was to evaluate the anticonvulsant activity of PID in rodent models of partial, secondarily generalized and sound-induced generalized seizures which focus on different methods of seizure induction, both acute... |
12598409 | Implication of nigral tachykinin NK3 receptors in the maintenance of hypertension in spontaneously hypertensive rats: a pharmacologic and autoradiographic study. | 1. The role of nigral tachykinin NK(1), NK(2) and NK(3) receptors in central cardiovascular regulation was studied by measuring the effects of selective agonists and antagonists on mean arterial pressure (MAP) and heart rate (HR) after bilateral microinjection into the substantia nigra of spontaneously hypertensive rat... |
12597494 | Application of a modified culture medium for the simultaneous counting of molds and yeasts and detection of aflatoxigenic strains of Aspergillus flavus and Aspergillus parasiticus. | Molds and yeasts from 91 samples of feed and raw materials used in feed formulation were enumerated on a new culture medium to which a beta cyclodextrin (beta-W7M 1.8-cyclodextrin) had been added. This medium was compared with other media normally used in laboratories for the routine analysis of fungi, such as Sabourau... |
12595686 | Giant supramolecular liquid crystal lattice. | Self-organized supramolecular organic nanostructures have potential applications that include molecular electronics, photonics, and precursors for nanoporous catalysts. Accordingly, understanding how self-assembly is controlled by molecular architecture will enable the design of increasingly complex structures. We repo... |
12595118 | Exploring the dynamic background of the developmental processes and cell reactions with the use of an ultraweak photon emission. | Any reactions of the living systems are to a great extent context-dependent. Meanwhile, the biological essence of a "context" remains to be obscure. We suggest that it may be based upon an ensemble of molecular-supramolecular oscillators, which have different characteristic times. For testing this hypothesis, we applie... |
12590566 | Memory effects based on intermolecular photoinduced proton transfer. | We have identified a strategy to communicate a chemical signal between two independent molecular components. One of them is a photoactive merocyanine that switches to a spiropyran, releasing a proton, when stimulated with visible light. The other is a 4,4'-pyridylpyridinium monocation that captures the released proton,... |
12590565 | Impact of multiple cation-pi interactions upon calix[4]arene substrate binding and specificity. | The cation-pi interaction influence on the conformation and binding of calix[4]arenes to alkali-metal cations has been studied using a dehydroxylated model. The model allows for the separation of cooperative cation-pi and electrostatic forces commonly found in the binding motifs found in calixarene complexes. Starting ... |
12590562 | Mechanism of charging and supercharging molecules in electrospray ionization. | The origin of the extent of charging and the mechanism by which multiply charged ions are formed in electrospray ionization have been hotly debated for over a decade. Many factors can affect the number of charges on an analyte ion. Here, we investigate the extent of charging of poly(propyleneimine) dendrimers (generati... |
12590551 | The bis-barium complex of a butterfly crown ether as a phototunable supramolecular catalyst. | Reversible phototuning of the catalytic efficiency of the bis-barium complex of azobis(benzo-18-crown-6) in the basic ethanolysis of anilide derivatives has been achieved by light-induced cis right arrow over left arrow trans interconversion of the azobenzene spacer unit of the catalyst. The geometry of the productive ... |
12590548 | Mechanically linked polycarbonate. | The synthesis, by solid-state copolymerization, and characterization of the first polycatenanes based on a commercial polymer are reported. Various amounts of a benzylic amide [2]catenane, the corresponding macrocycle, and a rigid bisphenol fluorene derivative have been quantitatively and homogeneously incorporated int... |
12590525 | Copper ion-induced activation and asymmetric benzoylation of 1,2-diols: kinetic chiral molecular recognition. | New catalytic ability of copper(II) ion has been exploited for monobenzoylation of 1,2-diols. The catalyst can be readily modified by ligation to acquire higher stereoselectivity. Highly effective kinetic resolution of dl-1,2-diols was achieved. The enantiodiscrimination process was clearly shown to be controlled by th... |
12590523 | Self-assembly of spherical colloids into helical chains with well-controlled handedness. | Physical constraint and capillary force have been combined to provide a generic approach to assemble achiral building blocks such as monodisperse spherical colloids into helical mesostructures. The key component of this process is an array of V-shaped grooves anisotropically etched in the surface of a Si(100) wafer. Th... |
12590507 | A [2]catenane constructed around a Ru(diimine)(3)(2+) complex used as a template. | A [2]catenane has been constructed using an octahedral complex of the Ru(diimine)( 2+)(3) family as a scaffold. Two diimine chelates have been incorporated in a ring prior to the ruthenium(II) complexation reaction. The macrocyclic complex thus obtained has been subsequently threaded by a long linear fragment containin... |
12589695 | End-grafted polysilane--an approach to single polymer science. | This Account describes our approach to single polymer science in which we use end-grafted polysilane. Single polymer science, by our definition, involves isolating and observing a single polymer chain and extracting its physical properties at the single molecule level. For this purpose, we developed the end-graft techn... |
12589694 | Solvation dynamics and proton transfer in supramolecular assemblies. | Water molecules confined in a supramolecular assembly control reactivity and dynamics of biological systems in a unique way. In a confined system, water molecules display an ultraslow component of solvation which is slower than that in bulk water by 2-4 orders of magnitude. The ultraslow component arises mainly from th... |
12588655 | Pharmacological disintegration of lipid rafts decreases specific tetramer binding and disrupts the CD3 complex and CD8 heterodimer in human cytotoxic T lymphocytes. | Accumulating evidence strongly supports the role of lipid rafts in the regulation of T-lymphocyte activation, but the organization and molecular composition of these cholesterol- and sphingolipid-rich membrane microdomains in different subsets of T cells remain poorly investigated. Here, we show that pharmacological di... |
12589029 | 17AAG: low target binding affinity and potent cell activity--finding an explanation. | The ansamycin geldanamycin (GM) and its derivative, 17AAG, now in early clinical trials in cancer patients, have potent activity against several cancer cells at low nanomolar concentrations. The main target of these drugs is the molecular chaperone heat shock protein 90. Contrary to the high antitumor potency, the affi... |
12589058 | Raft-mediated trafficking of apical resident proteins occurs in both direct and transcytotic pathways in polarized hepatic cells: role of distinct lipid microdomains. | In polarized hepatic cells, pathways and molecular principles mediating the flow of resident apical bile canalicular proteins have not yet been resolved. Herein, we have investigated apical trafficking of a glycosylphosphatidylinositol-linked and two single transmembrane domain proteins on the one hand, and two polytop... |
12589051 | Adaptor and clathrin exchange at the plasma membrane and trans-Golgi network. | We previously demonstrated, using fluorescence recovery after photobleaching, that clathrin in clathrin-coated pits at the plasma membrane exchanges with free clathrin in the cytosol, suggesting that clathrin-coated pits are dynamic structures. We now investigated whether clathrin at the trans-Golgi network as well as ... |
12589048 | Chemical genetic analysis of Apg1 reveals a non-kinase role in the induction of autophagy. | Macroautophagy is a catabolic membrane trafficking phenomenon that is observed in all eukaryotic cells in response to various stimuli, such as nitrogen starvation and challenge with specific hormones. In the yeast Saccharomyces cerevisiae, the induction of autophagy involves a direct signal transduction mechanism that ... |
12589047 | Chl4p and iml3p are two new members of the budding yeast outer kinetochore. | Kinetochore proteins contribute to the fidelity of chromosome transmission by mediating the attachment of a specialized chromosomal region, the centromere, to the mitotic spindle during mitosis. In budding yeast, a subset of kinetochore proteins, referred to as the outer kinetochore, provides a link between centromere ... |
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