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11559790 | Interaction of classical swine fever virus with membrane-associated heparan sulfate: role for virus replication in vivo and virulence. | Passage of native classical swine fever virus (CSFV) in cultured swine kidney cells (SK6 cells) selects virus variants that attach to the surface of cells by interaction with membrane-associated heparan sulfate (HS). A Ser-to-Arg change in the C terminus of envelope glycoprotein E(rns) (amino acid 476 in the open readi... |
11559649 | Homing commitment of lymphocytes activated in the human gastric and intestinal mucosa. | <h4>Background</h4>Gastric infection with the human pathogen Helicobacter pylori results in a large accumulation of IgA and IgM secreting cells in the gastric mucosa. The molecular mechanisms resulting in B cell migration to the gastric mucosa in H pylori infection are however not known.<h4>Aims</h4>To examine expressi... |
11557472 | Cellular uptake of two fluoroketolides, HMR 3562 and HMR 3787, by human polymorphonuclear neutrophils in vitro. | We analyzed the cellular accumulation of two new fluoroketolides, HMR 3562 and HMR 3787, by human polymorphonuclear neutrophils (PMN) in vitro. Both compounds were rapidly taken up by PMN, with a cellular-to-extracellular concentration ratio (C/E) of about 141 (HMR 3562) and 117 (HMR 3787) at 5 min, and this was follow... |
11557457 | RL-37, an alpha-helical antimicrobial peptide of the rhesus monkey. | Rhesus monkey bone marrow expresses a cathelicidin whose C-terminal domain comprises a 37-residue alpha-helical peptide (RL-37) that resembles human LL-37. Like its human counterpart, RL-37 rapidly permeabilized the membranes of Escherichia coli ML-35p and lysed liposomes that simulated bacterial membranes. When tested... |
11553572 | Epidemic population structure of Pseudomonas aeruginosa: evidence for a clone that is pathogenic to the eye and that has a distinct combination of virulence factors. | The genetic structure of a population of Pseudomonas aeruginosa, isolated from patients with keratitis, endophthalmitis, and contact lens-associated red eye, contact lens storage cases, urine, ear, blood, lungs, wounds, feces, and the environment was determined by multilocus enzyme electrophoresis. The presence and cha... |
11553541 | Role of ADP-ribosyltransferase activity of pertussis toxin in toxin-adhesin redundancy with filamentous hemagglutinin during Bordetella pertussis infection. | Pertussis toxin (PT) and filamentous hemagglutinin (FHA) are two major virulence factors of Bordetella pertussis. FHA is the main adhesin, whereas PT is a toxin with an A-B structure, in which the A protomer expresses ADP-ribosyltransferase activity and the B moiety is responsible for binding to the target cells. Here,... |
11553025 | Metalloendopeptidases EC 3.4.24.15 and EC 3.4.24.16 and bradykinin B2 receptors do not play important roles in renal wrap hypertension in rabbits. | 1. The aim of the present study was to determine the effects of the metalloendopeptidase (EP) 24.15 and 24.16 inhibitor N-[1-(R,S)-carboxy-3-phenylpropyl]-Ala-Aib-Tyr-p-aminobenzoate (JA-2) on haemodynamics and renal function in conscious rabbits with two-kidney, two-wrapped hypertension. We have also examined the role... |
11547852 | Cucurbituril for water treatment. Part II: Ozonation and oxidative regeneration of cucurbituril. | In Part I it was shown, that cucurbituril has high sorption capacities for the removal of reactive dyes from textile wastewater; despite the partial dissolution of this sorbent. Ozonation has been suggested as a regeneration step for loaded cucurbituril. Ozonation of loaded and pure cucurbituril was therefore evaluated... |
11547851 | Cucurbituril for water treatment. Part I: Solubility of cucurbituril and sorption of reactive dyes. | Cucurbituril was investigated regarding its potential as a sorbent for the removal of reactive dyes from model solutions and authentic wastewaters. The solubility of cucurbituril is low in pure water but increases in the presence of salts. When dyes sorbing onto cucurbituril are present, solubility is drastically decre... |
11544222 | Binding specificity of the Porphyromonas gingivalis heme and hemoglobin receptor HmuR, gingipain K, and gingipain R1 for heme, porphyrins, and metalloporphyrins. | Previous genetic and biochemical studies have confirmed that hemoglobin and hemin utilization in Porphyromonas gingivalis is mediated by the outer membrane hemoglobin and heme receptor HmuR, as well as gingipain K (Kgp), a lysine-specific cysteine protease, and gingipain R1 (HRgpA), one of two arginine-specific cystein... |
11536146 | Water-based nanoparticulate polymeric system for protein delivery. | This article features a new production technology for nanoparticles comprised of multicomponent polymeric complexes that are candidates for delivery vehicles of biological molecules such as proteins and drugs. Biocompatible and mostly natural polymers are fabricated into thermodynamically stable nanoparticles insoluble... |
11536137 | Sol-gel immobilization of serine proteases for application in organic solvents. | The serine proteases alpha-chymotrypsin, trypsin, and subtilisin Carlsberg were immobilized in a sol-gel matrix and the effects on the enzyme activity in organic media are evaluated. The percentage of immobilized enzyme is 90% in the case of alpha-chymotrypsin and the resulting specific enzyme activity in the transeste... |
11533201 | The pathogenicity of human immunodeficiency virus (HIV) type 1 Nef in CD4C/HIV transgenic mice is abolished by mutation of its SH3-binding domain, and disease development is delayed in the absence of Hck. | The human immunodeficiency virus type 1 (HIV-1) Nef protein is an important determinant of AIDS pathogenesis. We have previously reported that HIV-1 Nef is responsible for the induction of a severe AIDS-like disease in CD4C/HIV transgenic (Tg) mice. To understand the molecular mechanisms of this Nef-induced disease, we... |
11533193 | Displacement of YY1 by differentiation-specific transcription factor hSkn-1a activates the P(670) promoter of human papillomavirus type 16. | Transcription from human papillomavirus type 16 (HPV16) P(670), a promoter in the E7 open reading frame, is repressed in undifferentiated keratinocytes but becomes activated upon differentiation. We showed that the transient luciferase expression driven by P(670) was markedly enhanced in HeLa cells cotransfected with a... |
11533173 | Receptor binding transforms the surface subunit of the mammalian C-type retrovirus envelope protein from an inhibitor to an activator of fusion. | The envelope protein (Env) of murine leukemia viruses (MLVs) is composed of a surface subunit (SU) and a transmembrane subunit (TM), which mediates membrane fusion, resulting in infection. SU contains a discrete N-terminal receptor binding domain (RBD) that is connected to the remainder of Env by a short, proline-rich ... |
11533171 | A novel nonnucleoside inhibitor specifically targets cytomegalovirus DNA maturation via the UL89 and UL56 gene products. | 3-Hydroxy-2,2-dimethyl-N-[4([[5-(dimethylamino)-1-naphthyl]sulfonyl]amino)-phenyl]propanamide (BAY 38-4766) is a novel selective nonnucleoside inhibitor of cytomegalovirus (CMV) replication with an excellent safety profile. This compound and structural analogues inhibit neither viral DNA synthesis nor viral transcripti... |
11519784 | Influence of betacyclodextrin on the release of poorly soluble drugs from inert and hydrophilic heterogeneous polymeric matrices. | The release behavior of poorly soluble drugs (naproxen and ketoprofen) from inert (acrylic resins) and hydrophilic swellable (high-viscosity hydroxypropylmethylcellulose) tableted matrices containing betacyclodextrin (betaCD) was investigated. The results demonstrated that, in both cases, betaCD can enhance the rate of... |
11489387 | A stability study of tetracycline and tetracycline cyclodextrins in tablets using a new HPLC method. | A sensitive, rapid, reproducible, easy and precise reverse-phase high-performance liquid chromatographic assay for stability studies of tetracycline hydrochloride (TC.HCl) formulated with different excipients and techniques without using gradient elution, extraction methods, and at ambient temperature has been develope... |
11473349 | Structure and topology of a peptide segment of the 6th transmembrane domain of the Saccharomyces cerevisae alpha-factor receptor in phospholipid bilayers. | A detailed analysis of the structure of an 18-residue peptide AQSLLVPSIIFILAYSLK [M6(252-269, C252A)] in 1,2-dimyristoyl-sn-glycero-phosphocholine bilayers was carried out using solid state NMR and attenuated total reflection Fourier transform infrared spectroscopy. The peptide corresponds to a portion of the 6th trans... |
11574726 | Polymorphism of maleic hydrazide. I. | The third polymorph (denoted MH3) of maleic hydrazide (3,6-dihydroxypyridazine in the monolactim form, 6-hydroxy-3-pyridazinone, C4H4N2O2) has been studied by X-ray diffraction and shown to be monoclinic, space group P2(1)/n. Polymorph MH3 was found as the prevailing form along with the rare triclinic polymorph MH1, sp... |
11690058 | Self-assembly of amphiphiles into vesicles: a Brownian dynamics simulation. | We studied the vesicles of amphiphilic molecules using a Brownian dynamics simulation. An amphiphilic molecule is modeled as the rigid rod, and the hydrophobic interaction is mimicked by the local density potential of the hydrophobic particles. The amphiphilic molecules self-assemble into vesicles with bilayer structur... |
11567020 | Probing the effects of membrane cholesterol in the Torpedo californica acetylcholine receptor and the novel lipid-exposed mutation alpha C418W in Xenopus oocytes. | The effects of cholesterol on the ion-channel function of the Torpedo acetylcholine receptor (nAChR) and the novel lipid-exposed gain in function alpha C418W mutation have been investigated in Xenopus laevis oocytes. We found conditions to increase the cholesterol/phospholipid (C/P) molar ratio on the plasma membrane o... |
11562479 | Supramolecular chemistry: functional structures on the mesoscale. | Supramolecular chemistry deals with the chemistry and collective behavior of organized ensembles of molecules. In this so-called mesoscale regime, molecular building blocks are organized into longer-range order and higher-order functional structures via comparatively weak forces. As one of the modern frontiers in chemi... |
11557756 | Unhydroxylated triple helical collagen I produced in transgenic plants provides new clues on the role of hydroxyproline in collagen folding and fibril formation. | Human unhydroxylated homotrimeric triple-helical collagen I produced in transgenic plants was used as an experimental model to provide insights into the role of hydroxyproline in molecular folding and fibril formation. By using chemically cross-linked molecules, we show here that the absence of hydroxyproline residues ... |
11557754 | Enrichment of G-protein palmitoyltransferase activity in low density membranes: in vitro reconstitution of Galphai to these domains requires palmitoyltransferase activity. | Many signaling proteins are targeted to low density, sphingomyelin- and cholesterol-enriched membranes, also called lipid rafts. These domains organize receptor-mediated signaling events at the plasma membrane. Fatty acylation is one mechanism for targeting proteins to rafts. It was therefore of interest to determine i... |
11555657 | Hydrophobic amino acid residues in the acceptor binding site are main determinants for reaction mechanism and specificity of cyclodextrin-glycosyltransferase. | Cyclodextrin-glycosyltransferases (CGTases) (EC ) preferably catalyze transglycosylation reactions with glucosyl residues as acceptor, whereas the homologous alpha-amylases catalyze hydrolysis reactions using water as acceptor. This difference in reaction specificity is most likely caused by the acceptor binding site. ... |
11553636 | Folding and subunit assembly of photoreceptor peripherin/rds is mediated by determinants within the extracellular/intradiskal EC2 domain: implications for heterogeneous molecular pathologies. | Peripherin/rds is an integral membrane protein required for the elaboration of rod and cone photoreceptor outer segments in the vertebrate retina; it causes a surprising variety of progressive retinal degenerations in humans and dysmorphic photoreceptors in murine models if defective or absent. (Peripherin/rds is also ... |
11588385 | Ethyl 6-amino-2-methoxypyridine-3-carboxylate, interplay of molecular and supramolecular structure. | The title compound, C(9)H(12)N(2)O(3), crystallizes with two molecules in the asymmetric unit. There is extensive hydrogen bonding which results in the formation of a two-dimensional corrugated sheet. This supramolecular structure is determined by the formation of hydrogen-bonded chains resulting from the presence of a... |
11588373 | Host-guest-like thiamine-anion complexation in thiaminium bis(tetrafluoroborate). | In the title compound, 3-[(4-amino-2-methyl-5-pyrimidin-1-io)methyl]-5-(2-hydroxyethyl)-4-methylthiazolium(2+) bis(tetrafluoroborate), C(12)H(18)N(4)OS(2+).2BF(4)(-), the divalent thiamine cation (in the F conformation) is associated with BF(4)(-) anions via two characteristic bridging interactions between the thiazoli... |
11553774 | Characterization of the nucleotide-binding capacity and the ATPase activity of the PIP3-binding protein JFC1. | In this work, we demonstrate that the phosphatidylinositol 3,4,5-trisphosphate-binding protein JFC1 is an ATP-binding protein with magnesium-dependent ATPase activity. We show that JFC1 specifically binds to the ATP analog 8-azido-[alpha-(32)P]ATP. The affinity of JFC1 for [alpha-(32)P]ATP was 10x greater than its affi... |
11535830 | Functionalized xenon as a biosensor. | The detection of biological molecules and their interactions is a significant component of modern biomedical research. In current biosensor technologies, simultaneous detection is limited to a small number of analytes by the spectral overlap of their signals. We have developed an NMR-based xenon biosensor that capitali... |
11535827 | Dominant/recessive behavior in the expression of molecular information: self-assembly of inorganic macrocyclic architectures containing coordinatively unsaturated ligands. | The polytopic ligand 1 contains three different metal ion binding subunits forming two substructures that code for the self-assembly of two different coordination structures (helicate and grid type) under metal ion complexation. Reaction with Cu(II) and Zn(II) ions generates the coordinatively unsaturated architectures... |
11535814 | Partitioning of Thy-1, GM1, and cross-linked phospholipid analogs into lipid rafts reconstituted in supported model membrane monolayers. | As shown earlier, raft-like domains resembling those thought to be present in natural cell membranes can be formed in supported planar lipid monolayers. These liquid-ordered domains coexist with a liquid-disordered phase and form in monolayers prepared both from synthetic lipid mixtures and lipid extracts of the brush ... |
11535811 | Crystal structure of the human CD4 N-terminal two-domain fragment complexed to a class II MHC molecule. | The structural basis of the interaction between the CD4 coreceptor and a class II major histocompatibility complex (MHC) is described. The crystal structure of a complex containing the human CD4 N-terminal two-domain fragment and the murine I-A(k) class II MHC molecule with associated peptide (pMHCII) shows that only t... |
11535804 | Compaction of single DNA molecules induced by binding of integration host factor (IHF). | We studied the interaction between the integration host factor (IHF), a major nucleoid-associated protein in bacteria, and single DNA molecules. Force-extension measurements of lambda DNA and an analysis of the Brownian motion of small beads tethered to a surface by single short DNA molecules, in equilibrium with an IH... |
29712077 | Coil-Ring-Coil Block Copolymers as Building Blocks for Supramolecular Hollow Cylindrical Brushes. | Solvent-induced self-assembly of oligomer-substituted shape-persistent macrocycles leads to the formation of cylindrical aggregates, which have been fully characterized in solution. These aggregates, bound by nonspecific interactions, can be described as supramolecular hollow polymer brushes. |
29712078 | Towards Synthetic Adrenaline Receptors-Shape-Selective Adrenaline Recognition in Water. | A new rationally designed receptor molecule binds adrenaline derivatives in water. Its binding pattern imitates the interplay of noncovalent interactions operating in the natural receptor. High shape selectivity is achieved for the slim dopamine skeleton, and leads to rejection of substrates with an α-substituent, such... |
29712075 | Two Mechanisms of Slow Host-Guest Complexation between Cucurbit[6]uril and Cyclohexylmethylamine: pH-Responsive Supramolecular Kinetics. | 20 times more rapid is the complexation of the organic ammonium ion receptor cucurbit[6]uril (CB6) with cyclohexylmethylamine than with the cyclohexylmethylammonium species. Within the narrow pH region around the pK<sub>a</sub> value of the amine, the complexation kinetics are accelerated but the binding constant remai... |
29712070 | Metal-Mediated Self-Assembly of π-Bonded Benzoquinone Complexes into Polymers with Tunable Geometries. | Coordination of Mn(CO)<sub>3</sub><sup>+</sup> to the π system in hydroquinone facilitates proton loss to afford benzoquinone complexes. Subsequent σ coordination of the benzoquinone oxygen atoms to added metal ions results in neutral one-, two-, or three-dimensional quinoid polymers. The geometrical requirements of th... |
29712060 | From Structure to Function: A New Approach to Detect Functional Similarity among Proteins Independent from Sequence and Fold Homology. | Protein function is almost invariably linked with the specific recognition of substrates or endogenous ligands in particular binding pockets; proteins of related function should, therefore, share comparable recognition pockets. On the basis of this idea a new computer method has been developed to detect functional rela... |
29712056 | "Total Synthesis" Supramolecular Style: Design and Hydrogen-Bond-Directed Assembly of Ternary Supermolecules. | Getting the right balance between intermolecular interactions is crucial for the synthesis of supermolecules in a preconceived manner. The three-component supermolecule in the ternary cocrystal of 3,5-dinitrobenzoic acid, isonicotinamide, and 4-(dimethylamino)benzoic acid (1:1:1) assembles through a "primary" (between ... |
29712052 | Rational Design of Low Molecular Mass Organogelators: Toward a Library of Functional N-Acyl-1,ω-Amino Acid Derivatives. | N-Acyl amino acids RCONH(CH<sub>2</sub> )<sub>n</sub> COOR<sup>1</sup> represent a new family of organogelators that can be obtained in a combinatorial approach from libraries of activated acids and amino acids. The amounts required for gel formation in solvents such as DMF are less than 1 mg mL<sup>-1</sup> and the ge... |
29712044 | Hapten-Functionalized DNA-Streptavidin Nanocircles as Supramolecular Reagents in a Competitive Immuno-PCR Assay. | Analysis with nanorings: The endogeneous proteins of supramolecular DNA nanocircles, obtained in high yields from oligomeric precursors containing bisbiotinylated DNA and streptavidin, are conveniently functionalized with biotinylated hapten moieties. These modular conjugates can be used as reagents in a novel competit... |
29712042 | Sensing A Paradigm Shift in the Field of Molecular Recognition: From Selective to Differential Receptors. | Molecular recognition has evolved from a science designed to understand biological systems into a much more diverse area of research. While work continues to elucidate "nature's tricks" with respect to intermolecular interactions, much attention has turned to the perspective that molecular recognition, by design, can l... |
29712040 | A Large Dendritic Multiporphyrin Array as a Mimic of the Bacterial Light-Harvesting Antenna Complex: Molecular Design of an Efficient Energy Funnel for Visible Photons. | π-Electronic conjugation is not necessary to facilitate long-range energy migration and transfer: A rapid (k<sub>ENT</sub> =1.04×10<sup>9</sup> s<sup>-1</sup> ) and efficient (Φ<sub>EXT</sub> =71 %) energy transfer from the 28 photoexcited zinc porphyrin units to the focal free-base porphyrin unit occurs in a large, st... |
29712038 | Homo- and Heterochiral Supramolecular Tapes from Achiral, Enantiopure, and Racemic Promesogenic Formamides: Expression of Molecular Chirality in Two and Three Dimensions. | Enantiomorphous monolayers of enantiopure formamides form on a graphite surface, while the racemic compound does not undergo a spontaneous resolution under similar conditions. This difference in the two-dimensional behavior has been studied by scanning tunneling microscopy (see image of the racemate adsorbed on graphit... |
12914068 | Nanofabrication of helical peptide-shelled dendrimers. | This study describes nanofabrication of helical peptide-shelled dendrimers using a Langmuir monolayer technique. Poly(amido amine) dendrimers (G3) modified with poly(gamma-benzyl-L-glutamate) [number averaged degree of polymerization, n = 12, 17, and 34 (G3-PBLGs hereafter)] were newly prepared by graft polymerization ... |
12580105 | [Selective isolation of anethole from volatile oil of Foeniculum vulgare Mill by inclusion crystalline with chela-shape host]. | <h4>Aim</h4>To isolate the components from the volatile oil of Foeniculum vulgare Mill.<h4>Methods</h4>According to the function of molecular recognition of supramolecular chemistry, chela shape molecule, trans-1, 2-biphenyl-1, 2-acenaphthendiol was used as host molecule and the volatile oil of Foeniculum vulgare Mill ... |
12240414 | An ab initio study of the influence of crystal packing on the host-guest interactions of calix[4]arene crystal structures. | We report the first quantum mechanical calculations of p-tert-butylcalix[4]arene inclusion complexes in the crystalline state with geometrical aspects demonstrating good agreement with experiment, while comparison of the configurations calculated for an isolated complex and in the crystal, illustrate that crystal packi... |
12240400 | Intercalation of a pendant-arm tetraazamacrocycle into molybdenum disulfide. | A novel macrocycle-MoS2 nanocomposite has been synthesized and characterized using the exfoliation/restacking properties of LiMoS2, providing the first of a new family of intercalation compounds. |
12240397 | Self-assembly of a bis-urea macrocycle into a columnar nanotube. | A bis-urea macrocycle 1 was synthesized and shown to form extended nanotubular columns by X-ray crystallography. |
12240385 | Rhodizonate and croconate dianions as divergent hydrogen-bond acceptors in the self-assembly of supramolecular structures. | The C5O5(2-) and relatively unstable C6O6(2-) dianions, each serving as a hub for binding with a set of convergent NH donor groups of four phenylurea molecules, have been generated in situ and stabilized in nearly isostructural hydrogen-bonded host lattices. |
12240378 | Self-assembled nanoscale capsules between resorcin[4]arene derivatives and Pd(II) Pt(II) complexes. | Nanoscale molecular capsules have been prepared by self-assembly of resorcin[4]-arene derivatives and Pd(II) or Pt(II) complexes; the positively charged N-alkylpyridinium derivatives are encapsulated inside capsules due to strong cation-pi interactions. |
12240365 | Hydrogen bonded calixarene capsules kinetically stable in DMSO. | Half-life times up to 4 days in DMSO at room temperature are observed for the decomposition of dimeric capsules of urea substituted calix[4]arenes held together by a combination of hydrogen bonds, mechanical entanglement and cation-pi interactions. |
12240352 | First photosensitized enantiodifferentiating isomerization by optically active sensitizer immobilized in zeolite supercages. | Enantiodifferentiating photoisomerization of (Z)-cyclooctene sensitized by (R)- or (S)-1-methylheptyl benzoate immobilized in zeolite supercages afforded the respective enantiomer pair, (-)- and (+)-(E)-isomer (1E) in 5% enantiomeric excess, whilst racemic 1E was obtained upon homogeneous-phase photosensitization with ... |
12240348 | Interpenetration in [Cd(isonicotinate)2(1,2-bis(4-pyridyl)-ethane)0.5(H2O)]n, a novel octahedral polymer containing an unusual two-dimensional bilayer motif generated by self-assembly of rectangle building blocks. | A hydrothermally synthesized mixed-ligand molecular solid composed of pillared bilayers has been formulated; it presents a new remarkable three-dimensional architecture sustained by the catenation of two-fold decked layers, and exhibits intense photoluminescence upon photoexcitation at 314 nm. |
12240346 | A 3,12-connected vertice sharing adamantoid hydrogen bonded network featuring tetrameric clusters of cyclotriveratrylene. | The crystalline supramolecular complex [Sr(H2O)8][(CH3CN) [symbol: see text] (CTV)]4(H2O)4[Co(C2B9H11)2]2 features [(CH3CN) [symbol: see text] (CTV)] host-guest interactions, back-to-back tetrameric clusters of CTV host molecules and an extensive hydrogen bonding giving a 3,12-connected net. |
12240334 | Design, fabrication, and properties of macroscale supramolecular fibers consisted of fully hydrogen-bonded pseudo-polymer chains. | Macro-scale supramolecular fibers composed of hydrogen bonded pseudo-polymer chains of guanosine derivatives were fibricated, and physical properties of the fibers were investigated. |
12240322 | Synthesis of alkenylene-bridged macrocyclic silsesquioxanes by ruthenium or rhodium-catalyzed ring-closing reactions of bis(allyldimethylsilyl) groups. | Novel alkenylene-bridged oligosilsesquioxanes composed of half-caged structures with 16- or 17-membered rings as well as a titanium-containing molecule with a twisted 21-membered macrocycle have been synthesized by ruthenium or rhodium-catalyzed ring-closing reactions of silsesquioxanes with bis(allyldimethylsilyl) gro... |
12240298 | Characterisation of a hydroxymandelate oxidase involved in the biosynthesis of two unusual amino acids occurring in the vancomycin group of antibiotics. | ORF22 from the chloroeremomycin gene cluster has been cloned, expressed and characterised as a hydroxymandelate oxidase (HmO) that is involved in the formation of both (S)-4-hydroxyphenylglycine and (S)-3,5-dihydroxyphenylglycine. |
11948654 | Molecular recognition and supramolecular chemistry in the gas phase. | Supramolecular chemistry, in particular, the fields of molecular recognition and self-assembly, profit much from the development of soft ionization techniques and advanced methods for mass analysis and gas-phase chemistry. Vice versa, weakly bonded architectures and host-guest complexes represent a veritable challenge ... |
11828505 | Dendrimer-activated solid supports for nucleic acid and protein microarrays. | The generation of chemically activated glass surfaces is of increasing interest for the production of microarrays containing DNA, proteins, and low-molecular-weight components. We here report on a novel surface chemistry for highly efficient activation of glass slides. Our method is based on the initial modification of... |
11774841 | 1,4,7,10-tetrakis(2,2'-bipyridyl-5-ylmethyl-bis(2,2'-bipyridine) ruthenium(II))-1,4,7,10-tetraazacyclododecane, a macrocyclic sensor for positively charged species. | The luminescent behavior of the cyclen-based macrocycle L1 was investigated to establish its sensing ability for protons and transition metal ions. It acts as a good pH sensor in the neutral region. Its interaction with Cu (II) and Ni (II) is accompanied by quenching. The rate data for the interaction with Cu (II) were... |
11746952 | 1-X-3 motif in inter-protein recognition: structures, widespreading and possible practical application. | Similarities in the discrete mode and size of contact areas of a wide range of protein complexes allows us to suggest the existence of a limited number of types of inter-protein interactions. Comparison of structures of bound determinants indicates that the double-module, 1-X-3 type of motif is widespread in recognitio... |
11746951 | Exploration of sequence space for protein engineering. | The process of protein engineering is currently evolving towards a heuristic understanding of the sequence-function relationship. Improved DNA sequencing capacity, efficient protein function characterization and improved quality of data points in conjunction with well-established statistical tools from other industries... |
11746950 | Fine structural recognition specificities of IgE antibodies distinguishing amoxicilloyl and amoxicillanyl determinants in allergic subjects. | IgE antibodies in the sera of subjects allergic to beta-lactam antibiotics detect a spectrum of specificities ranging from side-chain groups to an entire penicillin or cephalosporin molecule. In addition to such structural heterogeneity of allergenic determinants, IgE antibodies in the sera of different allergic subjec... |
11746949 | One-step purification of glucoamylase by affinity precipitation with alginate. | It was found that alginate binds to glucoamylase, presumably through the recognition of starch binding domain of the latter. The present work exploits this for purification of glucoamylases from commercial preparation of Aspergillus niger and crude culture filtrate of Bacillus amyloliquefaciens by affinity precipitatio... |
11746948 | Survey of the year 2000 commercial optical biosensor literature. | We have compiled a comprehensive list of the articles published in the year 2000 that describe work employing commercial optical biosensors. Selected reviews of interest for the general biosensor user are highlighted. Emerging applications in areas of drug discovery, clinical support, food and environment monitoring, a... |
11746947 | The hidden code in genomics: a tool for gene discovery. | Among new insights coming from the completion of sequencing of the human genome, reported in Nature and Science, are clues of how evolution has increased the complexity of species, and in particular how the genetic code has enabled this process. It is clear that life has not only evolved by increasing the number of gen... |
11746946 | Current and emerging commercial optical biosensors. | The field of commercial optical biosensors is rapidly evolving, with new systems and detection methods being developed each year. This review outlines the currently available biosensor hardware and highlights unique features of each platform. Affinity-based biosensor technology, with its high sensitivity, wide versatil... |
11724384 | Effect of alpha-, beta- and gamma-cyclodextrins on oxygen evolution by the thylakoid membrane. influence of pH and temperature. | The present work investigates the effect of alpha-, beta- and gamma-cyclodextrins (CD), i.e., alpha-CD, beta-CD and gamma-CD, on the oxygen evolution activity, the protein content and the uv-vis spectroscopic characteristics of thylakoid membranes. To study the pH-dependence, the thylakoids were incubated with the cycl... |
11699838 | Terfenadine-beta-Cyclodextrin inclusion complex with antihistaminic activity enhancement. | Terfenadine, an antihistaminic drug, has relatively low bioavailability after oral administration due to its limited solubility in water. To enhance the antihistaminic activity of terfenadine, the terfenadine-beta-cyclodextrin (1:2) inclusion complex was prepared by the neutralization method. The solubility and dissolu... |
11699826 | Transdermal lontophoresis and skin retention of piroxicam from gels containing piroxicam: hydroxypropyl-beta-cyclodextrin complexes. | Iontophoretic transport of piroxicam (Px) across porcine ear skin in vitro was investigated. Cathodal iontophoresis of negatively charged Px was carried out from gel formulations containing Px as an inclusion complex with hydroxypropl-beta-cyclodextrin (HP-beta-CD). From the gels, following a 7h application period at 0... |
11693566 | Direct structure refinement of high molecular weight proteins against residual dipolar couplings and carbonyl chemical shift changes upon alignment: an application to maltose binding protein. | The global fold of maltose binding protein in complex with beta-cyclodextrin has been determined using a CNS-based torsion angle molecular dynamics protocol involving direct refinement against dipolar couplings and carbonyl chemical shift changes that occur upon alignment. The shift changes have been included as struct... |
11693529 | Transthyretin: a review from a structural perspective. | Transthyretin (formerly called prealbumin) plays important physiological roles as a transporter of thyroxine and retinol-binding protein. X-ray structural studies have provided information on the active conformation of the protein and the site of binding of both ligands. Transthyretin is also one of the precursor prote... |
11693527 | Polyisoprenyl glycolipids as targets of CD1-mediated T cell responses. | T cells are well known to recognize peptide antigens presented by major histocompatibility (MHC) class I or class II molecules. More recently, the CD1 family of antigen-presenting molecules has been shown to present both mammalian and microbial glycolipid antigens for specific recognition by T cells. Human CD1c protein... |
11693521 | Synthetic genes for the elucidation of glycosylation codes for arabinogalactan-proteins and other hydroxyproline-rich glycoproteins. | Hydroxyproline-rich glycoproteins (HRGPs) are ubiquitous architectural components of the growing plant cell wall, accounting for as much as 10-20% of the dry weight. HRGPs are implicated in all aspects of plant growth and development, including responses to stress. The HRGP superfamily contains three major groups which... |
11693520 | Life behind cell walls: paradigm lost, paradigm regained. | This review of the living cell wall and its protein components is in two parts. The first is anecdotal. A personal account spanning over 40 years research may perhaps be an antidote to one stereotypical view of scientists as detached and humorless. The second part deals with the meaning of function, particularly as it ... |
11681704 | Factors that determine the unusually low reduction potential of cytochrome c550 in cyanobacterial photosystem II. | A new purification protocol for cytochrome c550 (cyt c550) from His-tagged SYnechocYstis PCC 6803 photosystem II (PSII) was developed which allows the protein to be isolated in high yield and purity. Electron paramagnetic resonance spectroscopy of cyt c550, both free in solution and in intact PSII preparations, yields ... |
11681573 | Enantioseparation of phenothiazines in capillary zone electrophoresis using cyclodextrins as chiral selectors. | In this study, enantioseparations of five phenothiazines, including promethazine, ethopropazine, trimeprazine, methotrimeprazine, and thioridazine, in cyclodextrin (CD)-modified capillary zone electrophoresis were investigated using a phosphate buffer (40 mM) at pH 3.0. We focussed on the separation of phenothiazines w... |
11681584 | Analysis of enantiomers giving partially overlapped peaks by using different treatments of the chromatographic ultraviolet signals: quantification of pseudoephedrine enantiomers. | Different strategies for the quantification of partially coeluting optical isomers have been investigated. The methods tested are based on the use of different features as the analytical UV signals: peak heights, perpendicular drop areas, first and second derivatives of the chromatograms, peak areas obtained by deconvo... |
11678194 | Enantioseparation of linear and cyclic chiral bis(phenethyl)amines by means of cyclodextrin-modified capillary electrophoresis. | For two years drugs introduced to the market have had- to be enantiomerically pure. Rapid and cheap methods of high reproducibility must, therefore, be available for evaluation of enantiomeric purity. Within the framework of a larger project dealing with chiral recognition of phenethylamines by means of native and deri... |
11676293 | Structural distribution of mutations associated with familial amyloidotic polyneuropathy in human transthyretin. | The human plasma protein transthyretin (TTR) is a highly stable soluble homotetrameric protein. Still, conformational changes in the wild type protein can lead to self-assembly into insoluble amyloid fibrils. In addition, 74 point mutations are known to enhance amyloid formation causing familial amyloidotic polyneuropa... |
11669455 | Pharmacokinetics of the beta-carboline norharman in man. | In healthy subjects, pharmacokinetics were characterised using single oral and sublingual administrations of the beta-carboline norharman. For this purpose, norharman levels in blood plasma were measured up to 90-105 min after both routes of administration. Dose proportionality of three different single oral doses of n... |
11605760 | Chiral discrimination of limonene by use of beta-cyclodextrin-coated quartz-crystal-microbalances (QCMs) and data evaluation by artificial neuronal networks. | The enantiomeric composition of the chiral flavoring agent limonene was analyzed by means of a quartz-crystal microbalance (QCM) sensor. As chiral selectors three different modified beta-cyclodextrins were investigated. The selector molecules were applied as mixtures in different polysiloxane matrices. The chiral separ... |
11605750 | Multidimensional on-line solid-phase extraction (SPE) using restricted access materials (RAM) in combination with molecular imprinted polymers (MIP). | A novel, multidimensional SPE sample-processing platform for complex fluids, which relies on the combination of small LC columns packed with restricted access materials (RAM) and molecular imprinted polymers (MIP) is described. It is called the Six-S ProcEdure (Six-SPE). Six-SPE involves a size-selective sample-separat... |
11604026 | A nonlinear group contribution method for predicting the free energies of inclusion complexation of organic molecules with alpha- and beta-cyclodextrins. | A group-contribution method was developed for calculating the binding constants or the free energies of complexation between native alpha- or beta-cyclodextrin (CD) and organic guest molecules. The nonlinear models for binary (1:1 stoichiometry) complexes of alpha- and beta-CDs were derived with squared correlation coe... |
11603839 | Control of electron transfer in supramolecular systems. | The fluorescence quantum yield of zinc porphyrin (ZnP) covalently linked to 9,10-bis(phenylethynyl)anthracene (AB) is strongly dependent upon the solvent properties. The bichromophoric system ZnP-AB exhibits 'normal' zinc porphyrin fluorescence in solvents that cannot coordinate to the central zinc atom. In contrast, i... |
11603833 | Triplet states as non-radiative traps in multichromophoric entities: single molecule spectroscopy of an artificial and natural antenna system. | Energy transfer in antenna systems, ordered arrays of chromophores, is one of the key steps in the photosynthetic process. The photophysical processes taking place in such multichromophoric systems, even at the single molecule level, are complicated and not yet fully understood. Instead of directly studying individual ... |
11599082 | Charge-reduced nano electrospray ionization combined with differential mobility analysis of peptides, proteins, glycoproteins, noncovalent protein complexes and viruses. | This study explores the potential of a novel electrospray-based method, termed gas-phase electrophoretic mobility molecular analysis (GEMMA), allowing the molecular mass determination of peptides, proteins and noncovalent biocomplexes up to 2 MDa (dimer of immunglobulin M). The macromolecular ions were formed by nano e... |
11599077 | Study of gas-phase molecular recognition using Fourier transform ion cyclotron resonance mass spectrometry (FTICR/MS). | The application of Fourier transform ion cyclotron resonance (FTICR) mass spectrometry to the quantitative study of molecular recognition in the gas phase is reviewed. Because most quantitative measurements are dependent on accurate determination of the pressure of a neutral reagent, methods for accurate pressure measu... |
11596945 | Spirocyclopropanated bicyclopropylidenes: straightforward preparation, physical properites, and chemical transformations. | Perspirocyclopropanated bicyclopropylidene (6) was prepared in three steps from 7-cyclopropylidenedispiro[2.0.2.1]heptane (4) (24% overall) or, more efficiently, through dehalogenative coupling of 7,7-dibromo[3]triangulane (15) (82%). This type of reductive dimerization turned out to be successful for the synthesis of ... |
11596941 | Imprinting of chiral molecular recognition sites in thin TiO2 films associated with field-effect transistors: novel functionalized devices for chiroselective and chirospecific analyses. | (R)- or (S)-2-Methylferrocene carboxylic acids, (R)-1 or (S)-1, (R)- or (S)-2-phenylbutanoic acid, (R)-2 or (S)-2, and (R)- or (S)-2-propanoic acid, (R)-3 or (S)-3, can be imprinted in thin TiO2 films on the gate surface of ion-sensitive field-effect transistor (ISFET) devices. The imprinting is performed by hydrolyzin... |
11596935 | Olefin metatheses in metal coordination spheres: versatile new strategies for the construction of novel monohapto or polyhapto cyclic, macrocyclic, polymacrocyclic, and bridging ligands. | The broad applicability of the title reaction is established through studies of neutral and charged, coordinatively saturated and unsaturated, octahedral and square planar rhenium, platinum, rhodium, and tungsten complexes with cyclopentadienyl, phosphine, and thioether ligands which contain terminal olefins. Grubbs' c... |
11596855 | Polyamines and cell migration. | Leeuwenhoek first described polyamines in 1677, but active investigation did not begin until the 1970's. When intracellular polyamine levels are reduced by inhibitors, mutation, or transfection, severe reductions occur in cell division, cell differentiation, and cell migration. These effects are not difficult to demons... |
11594048 | Cationic dye-sensitized degradation of sodium hyaluronate through photoinduced electron transfer in the upper excited state. | The formation of ground-state complexes of methylene blue (MB) and thionine (TN) with sodium hyaluronate (NaHA) was clearly observed by means of absorption spectra in aqueous solution. Irradiation of the complexes using 313 nm light caused significant degradation of NaHA under oxygen and argon. However, the use of visi... |
11594391 | Chiral supercritical fluid chromatography on porous graphitic carbon using commercial dimethyl beta-cyclodextrins as mobile phase additive. | Using dimethylated-beta-cyclodextrin mixtures (MeCD) as chiral selectors in CO2-polar modifier mobile phase and porous graphitic carbon as solid-phase, chiral supercritical (or subcritical) fluid chromatography was performed. The adsorbed quantity of MeCD onto the porous graphitic carbon (Hypercarb) was measured for va... |
11592690 | Molecular dynamics simulation of n-dodecyl phosphate aggregate structures. | Aggregates of n-dodecyl phosphate present an attractive model system of simple phospholipid amphiphile supramolecular structures for study by molecular dynamics simulation, since these systems have previously been studied experimentally under various conditions. A detailed molecular dynamics description of the properti... |
11591811 | Mechanism and role of PDZ domains in signaling complex assembly. | PDZ domains are protein-protein recognition modules that play a central role in organizing diverse cell signaling assemblies. These domains specifically recognize short C-terminal peptide motifs, but can also recognize internal sequences that structurally mimic a terminus. PDZ domains can therefore be used in combinati... |
11589296 | Experimental designs to investigate capillary electrophoresis-electrospray ionization-mass spectrometry enantioseparation with the partial-filling technique. | An experimental design approach is described to evaluate the main electrophoretic parameters involved in the enantioseparation of pharmaceuticals by capillary electrophoresis (CE) coupled to electrospray ionization-mass spectrometry (ESI-MS). For all experiments, the partial-filling technique was applied to avoid the c... |
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