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11829517 | New basic membrane-destabilizing peptides for plasmid-based gene delivery in vitro and in vivo. | We have designed new basic amphiphilic peptides, ppTG1 and ppTG20 (20 amino acids), and evaluated their efficiencies in vitro and in vivo as single-component gene transfer vectors. ppTG1 and ppTG20 bind to nucleic acids and destabilize liposomes consisting of 1-palmitoyl-2-oleoylphosphatidylcholine (POPC) and cholester... |
11829509 | Structural clusters of evolutionary trace residues are statistically significant and common in proteins. | Given the massive increase in the number of new sequences and structures, a critical problem is how to integrate these raw data into meaningful biological information. One approach, the Evolutionary Trace, or ET, uses phylogenetic information to rank the residues in a protein sequence by evolutionary importance and the... |
11829616 | Selective detection and assignment of the solution NMR signals of bacteriochlorophyll a in a reconstituted subunit of a light-harvesting complex. | High-resolution solution NMR spectra have been obtained for bacteriochlorophyll (BChl) a molecules in a biologically functional subunit of a bacterial core light-harvesting complex based on a modified reconstitution method. The reconstituted subunit of pigment-integral membrane polypeptides is stable and homogeneous at... |
11829609 | Metallacycles of porphyrins as building blocks in the construction of higher order assemblies through axial coordination of bridging ligands: solution- and solid-state characterization of molecular sandwiches and molecular wires. | Treatment of the octahedral Ru(II)-dimethyl sulfoxide complexes trans-RuCl(2)(dmso-S)(4) (1), trans-RuCl(2)(dmso-O)(2)(CO)(2) (2), and trans-RuCl(2)(dmso)(3)(CO) (3) with a stoichiometric amount of 5,10-bis(4'-pyridyl)-15,20-diphenylporphyrin (4'-cis-DPyP) yields, after chromatographic purification, the novel 2+2 molec... |
11829585 | Novel isomerically pure tetrasubstituted allylboronates: stereocontrolled synthesis of alpha-exomethylene gamma-lactones as aldol-like adducts with a stereogenic quaternary carbon center. | In spite of their inherent isomerization tendency and low reactivity, 1-alkoxycarbonyl vinylcopper(I) intermediates from the conjugate addition of organocuprates onto acetylenic esters were trapped with very high cis-addition selectivity with iodomethylboronic esters in the presence of HMPA. The resulting isomerically ... |
11829583 | From achiral porphyrins to template-imprinted chiral aggregates and further. Self-replication of chiral memory from scratch. | The presence of 10-13 M of chiral clusters of aromatic amino acids addresses aggregation of opposite-charged achiral porphyrin towards the formation of smart chiral assemblies. The latter supramolecular complexes are able to self-propagate and transfer their chiral information with a 100% yield. The chiral bias occurs ... |
11829643 | Behaviors of D- and L-lactic acids during the brewing process of sake (Japanese rice wine). | The amounts of D- and L-lactic acids during the brewing process of sake were determined by capillary electrophoresis using 2-hydroxypropyl-beta-cyclodextrin as a chiral selector. Because L-lactic acid, which prevents the growth of nonuseful microorganisms, is a raw material of sake, the ratio of L-lactic acid to total ... |
11829764 | Effect of C-domain N-glycosylation and deletion on rat pancreatic alpha-amylase secretion and activity. | Even though all animal alpha-amylases include glycosylation sequons (Asn-Xaa-Thr/Ser) in their sequences, amylases purified from natural sources are not quantitatively glycosylated. When wild-type rat pancreatic alpha-amylase, which contains two glycosylation sequons, was expressed in animal cell lines the protein disp... |
11829758 | Complete sequence, recombinant analysis and binding to laminins and sulphated ligands of the N-terminal domains of laminin alpha3B and alpha5 chains. | The N-terminal sequences of mouse laminin alpha3B and alpha5 chains have been completed and demonstrate the presence of a signal peptide followed by a complete laminin N-terminal (LN) module (domain VI). These signal peptides were released after recombinant production of larger fragments comprising domains VI/V (45-65 ... |
11829742 | Lipid deprivation increases surfactant phosphatidylcholine synthesis via a sterol-sensitive regulatory element within the CTP:phosphocholine cytidylyltransferase promoter. | Lipid-deprived mice increase alveolar surfactant disaturated phosphatidylcholine (DSPtdCho) synthesis compared with mice fed a standard diet by increasing expression of CTP:phosphocholine cytidylyltransferase (CCT), the rate-limiting enzyme for DSPtdCho synthesis. We previously observed that lipid deprivation increases... |
11827830 | One from column A and two from column B: the benefits of phage display in molecular-recognition studies. | Recent uses of phage-displayed combinatorial peptide and cDNA libraries have proven invaluable in mapping protein-protein interactions, protein-drug interactions, and the generation of 'molecular therapeutics'. This article reviews some of the findings of the past year and points out some of the pros and cons of phage ... |
11826114 | Repellent guidance of regenerating optic axons by chondroitin sulfate glycosaminoglycans in zebrafish. | We analyzed the role of chondroitin sulfate (CS) glycosaminoglycans, putative inhibitors of axonal regeneration in mammals, in the regenerating visual pathway of adult zebrafish. In the adult, CS immunoreactivity was not detectable before or after an optic nerve crush in the optic nerve and tract but was constitutively... |
11826063 | Modeling the excitability of mammalian nerve fibers: influence of afterpotentials on the recovery cycle. | Human nerve fibers exhibit a distinct pattern of threshold fluctuation following a single action potential known as the recovery cycle. We developed geometrically and electrically accurate models of mammalian motor nerve fibers to gain insight into the biophysical mechanisms that underlie the changes in axonal excitabi... |
11823431 | Modular self-assembly of a Y-shaped multiprotein complex from seven nucleoporins. | Now that it is likely that all yeast nucleoporins are known, one of the ultimate goals is the in vitro assembly of the entire nuclear pore complex from its approximately 30 individual components. Here, we report the reconstitution of seven proteins (Nup133p, Nup145p-C, Nup120p, Nup85p, Nup84p, Seh1p and Sec13p) into a ... |
11823417 | The dynamin A ring complex: molecular organization and nucleotide-dependent conformational changes. | Here we show that Dictyostelium discoideum dynamin A is a fast GTPase, binds to negatively charged lipids, and self-assembles into rings and helices in a nucleotide-dependent manner, similar to human dynamin-1. Chemical modification of two cysteine residues, positioned in the middle domain and GTPase effector domain (G... |
11820897 | Surprises in the energetics of host-guest anion binding to calix[4]pyrrole. | Contrary to common expectation, calorimetric measurements do not corroborate the preference of calix[4]pyrrole for fluoride over chloride in acetonitrile solution. |
11820889 | Predicting experimental complexation-induced changes in (1)H NMR chemical shift for complexes between zinc-porphyrins and amines using the ab initio/GIAO-HF methodology. | Ab initio calculations were carried out on zinc-porphyrins complexed to several amines: N-(3,5-dimethyl-pyridin-4-yl)-formamide, 1,4-diazabiciclo[2.2.2]octane (DABCO), and 1-azabiciclo[2.2.2]octane (quinuclidine). The proton chemical shifts of these complexes were calculated ab initio at the GIAO-HF/6-311G//HF/3-21G le... |
11820932 | Kinetic studies of novel di- and tri-propionate substrates for the chicken red blood cell enzyme coproporphyrinogen oxidase. | Coproporphyrinogen oxidase is an important enzyme in heme biosynthesis and catalyses the sequential oxidative decarboxylation of propionates on the A and B rings of the porphyrinogen ring. The effects of substituents on the C and D rings have not been systematically evaluated for their effects on the kinetic constants,... |
11817961 | Ferrocene encapsulated within symmetric dendrimers: a deeper understanding of dendritic effects on redox potential. | Ferrocene has been encapsulated within a symmetric ether-amide dendritic shell and its redox potential monitored in a variety of solvents. The dendritic effect generated by the branched shell is different in different solvents. In less polar, non hydrogen bond donor solvents, attachment of the branched shell to ferroce... |
11817957 | Complexation and chiral recognition thermodynamics of 6-amino-6-deoxy-beta-cyclodextrin with anionic, cationic, and neutral chiral guests: counterbalance between van der Waals and coulombic interactions. | The stability constant (K), standard free energy (Delta G degrees), enthalpy (Delta H degrees), and entropy changes (T Delta S degrees) for the complexation of 6-amino-6-deoxy-beta-cyclodextrin with more than 50 negatively or positively charged as well as neutral guests, including 22 enantiomer pairs, have been determi... |
11818382 | Effect of the enzyme inhibitor, phenylmethylsulfonyl fluoride, on the IOP profiles of topical anandamides. | <h4>Purpose</h4>Earlier studies have suggested that the intraocular pressure (IOP) effects of topical arachidonylethanolamide (AEA) are mediated through its fatty acid metabolite, rather than through AEA, per se. The purpose of this study was to investigate whether the topical anandamides AEA and arachidonyl propionitr... |
11814440 | Mixed acetals of cyclodextrins. Preparation of hexakis-, heptakis- and octakis[2,6-di-O-(methoxydimethyl)methyl]-alpha-, beta- and gamma-cyclodextrins. | The proton-catalyzed addition of 2-methoxypropene to alpha-, beta- and gamma-cyclodextrins resulted in hexakis-, heptakis-, and octakis[2,6-di-O-(methoxydimethyl)methyl]-alpha-, beta- and gamma-cyclodextrins, but no reaction was observed of CD-s with 2,2-dimethoxypropane. The mixed acetal-type compounds can be alkylate... |
11813199 | Human immunodeficiency virus envelope-dependent cell-cell fusion: a quantitative fluorescence cytometric assay. | <h4>Background</h4>In vitro fusion of transfected cells expressing the human immunodeficiency virus (HIV) envelope proteins gp120/gp41, with target cells expressing CD4, and a suitable chemokine coreceptor is used widely to investigate the mechanisms of molecular recognition and membrane fusion involved in the entry of... |
11809900 | Padlock oligonucleotides as a tool for labeling superhelical DNA. | Labeling of a covalently closed circular double-stranded DNA was achieved using a so-called 'padlock oligonucleotide'. The oligonucleotide was targeted to a sequence which is present in the replication origin of phage f1 and thus in numerous commonly used plasmids. After winding around the double-stranded target DNA se... |
11809877 | Supercoiling, knotting and replication fork reversal in partially replicated plasmids. | To study the structure of partially replicated plasmids, we cloned the Escherichia coli polar replication terminator TerE in its active orientation at different locations in the ColE1 vector pBR18. The resulting plasmids, pBR18-TerE@StyI and pBR18-TerE@EcoRI, were analyzed by neutral/neutral two-dimensional agarose gel... |
11809793 | Rap1 functions as a key regulator of T-cell and antigen-presenting cell interactions and modulates T-cell responses. | Activation of T cells by antigen requires adhesive interactions with antigen-presenting cells (APC) in which leukocyte function-associated antigen 1 (LFA-1) and intercellular adhesion molecules (ICAMs) are important. However, it is not well understood what signaling molecules regulate this process and how the modulatio... |
11805232 | Heteromultimeric P2X(1/2) receptors show a novel sensitivity to extracellular pH. | Rat P2X(1) and P2X(2) subunits were coexpressed in defolliculated Xenopus oocytes and the resultant P2X receptors studied under voltage-clamp conditions. Extracellular ATP elicited biphasic inward currents, involving an initial rapidly inactivating (P2X(1)-like) component and a later slowly inactivating (P2X(2)-like) c... |
11807082 | In vitro identification of Rns-regulated genes. | To identify Rns-regulated genes, a maltose binding protein (MBP)-Rns fusion protein was used to isolate DNA fragments from enterotoxigenic Escherichia coli genomic DNA that carry Rns binding sites. In vivo transcription fusion analysis shows that Rns positively regulates the expression of the open reading frame of yiiS... |
11806946 | C-deuterated alanine: a new label to study membrane protein structure using site-specific infrared dichroism. | The helix tilt and rotational orientation of the transmembrane segment of M2, a 97-residue protein from the Influenza A virus that forms H(+)-selective ion channels, have been determined by attenuated total reflection site-specific infrared dichroism using a novel labeling approach. Triple C-deuteration of the methyl g... |
11806944 | Protonation and stability of the globular domain of influenza virus hemagglutinin. | A partial dissociation of the HA1 subunits of influenza virus hemagglutinin (HA) is considered to be the initial step of conformational changes of the HA ectodomain leading to a membrane fusion active conformation (L. Godley, J. Pfeifer, D. Steinhauer, B. Ely, G. Shaw, R. Kaufman, E. Suchanek, C. Pabo, J.J. Skehel, D.C... |
11806939 | Orientation distributions for cytochrome c on polar and nonpolar interfaces by total internal reflection fluorescence. | The formation of chemisorbed monolayers of yeast cytochrome c on both uncharged polar and nonpolar soft surfaces of organic self-assembled monolayers (SAM) on solid inorganic substrates was followed in situ by polarized total internal reflection fluorescence. Two types of nonpolar surfaces and one type of uncharged pol... |
11806936 | The 7.5-A electron density and spectroscopic properties of a novel low-light B800 LH2 from Rhodopseudomonas palustris. | A novel low-light (LL) adapted light-harvesting complex II has been isolated from Rhodopseudomonas palustris. Previous work has identified a LL B800-850 complex with a heterogeneous peptide composition and reduced absorption at 850 nm. The work presented here shows the 850 nm absorption to be contamination from a high-... |
11806930 | Stalk model of membrane fusion: solution of energy crisis. | Membrane fusion proceeds via formation of intermediate nonbilayer structures. The stalk model of fusion intermediate is commonly recognized to account for the major phenomenology of the fusion process. However, in its current form, the stalk model poses a challenge. On one hand, it is able to describe qualitatively the... |
11806923 | Cyclodextrin-induced lipid lateral separation in DMPC membranes: (2)H nuclear magnetic resonance study. | Cholesteryl cyclodextrins, obtained by grafting a cholesterol moiety on the oligosaccharide core, combine the size selectivity of the cyclodextrin cavity with the carrier properties of model membrane systems such as micelles or liposomes. The cholesteryl cyclodextrins were incorporated as guests in chain perdeuterated ... |
11806917 | Reticulated lipid probe fluorescence reveals MDCK cell apical membrane topography. | High spatial resolution confocal microscopy of young MDCK cells stained with the lipophilic probe 1,1'-dihexadecyl-3,3,3',3'- tetramethylindocarbocyanine perchlorate (DiIC(16)) revealed a reticulated fluorescence pattern on the apical membrane. DiIC(16) was delivered as crystals to live cells to minimize possible solve... |
11806905 | Clamped-filament elongation model for actin-based motors. | Although actin-based motility drives cell crawling and intracellular locomotion of organelles and certain pathogens, the underlying mechanism of force generation remains a mystery. Recent experiments demonstrated that Listeria exhibit episodes of 5.4-nm stepwise motion corresponding to the periodicity of the actin fila... |
11803134 | Physicochemical characterization and in vitro dissolution behavior of nicardipine-cyclodextrins inclusion compounds. | Inclusion complexation between nicardipine hydrochloride (NC), a calcium-channel antagonist, and beta-cyclodextrin (beta-CD) or hydroxypropyl-beta-cyclodextrin (HPbetaCD) was evaluated in aqueous environment and in solid state. The phase solubility profiles with both cyclodextrins (CDs) were classified as A(L)-type, in... |
11803128 | Interaction of naproxen with noncrystalline acetyl beta- and acetyl gamma-cyclodextrins in the solid and liquid state. | Randomly acetylated, amorphous beta-cyclodextrin (AcbetaCd) and gamma-cyclodextrin (AcgammaCd), having an average substitution degree per anhydroglucose unit, respectively, of 1.1 and 0.95 (approximately 7.7 acetyl residues per macrocycle), were investigated for their interactions in the solid and liquid state with nap... |
11801652 | Induction of MHC class I presentation of exogenous antigen by dendritic cells is controlled by CD4+ T cells engaging class II molecules in cholesterol-rich domains. | We investigated interactions between CD4+ T cells and dendritic cells (DC) necessary for presentation of exogenous Ag by DC to CD8+ T cells. CD4+ T cells responding to their cognate Ag presented by MHC class II molecules of DC were necessary for induction of CD8+ T cell responses to MHC class I-associated Ag, but their... |
11799188 | Single mutation in the flavivirus envelope protein hinge region increases neurovirulence for mice and monkeys but decreases viscerotropism for monkeys: relevance to development and safety testing of live, attenuated vaccines. | A chimeric yellow fever (YF) virus/Japanese encephalitis (JE) virus vaccine (ChimeriVax-JE) was constructed by insertion of the prM-E genes from the attenuated JE virus SA14-14-2 vaccine strain into a full-length cDNA clone of YF 17D virus. Passage in fetal rhesus lung (FRhL) cells led to the emergence of a small-plaqu... |
11799182 | Structure of equine infectious anemia virus matrix protein. | The Gag polyprotein is key to the budding of retroviruses from host cells and is cleaved upon virion maturation, the N-terminal membrane-binding domain forming the matrix protein (MA). The 2.8-A resolution crystal structure of MA of equine infectious anemia virus (EIAV), a lentivirus, reveals that, despite showing no s... |
11799180 | Internalization of echovirus 1 in caveolae. | Echovirus 1 (EV1) is a human pathogen which belongs to the Picornaviridae family of RNA viruses. We have analyzed the early events of infection after EV1 binding to its receptor alpha 2 beta 1 integrin and elucidated the route by which EV1 gains access to the host cell. EV1 binding onto the cell surface and subsequent ... |
11799176 | Segregation of CD4 and CXCR4 into distinct lipid microdomains in T lymphocytes suggests a mechanism for membrane destabilization by human immunodeficiency virus. | Recent evidence has suggested that plasma membrane sphingolipids and cholesterol spontaneously coalesce into raft-like microdomains and that specific proteins, including CD4 and some other T-cell signaling molecules, sequester into these rafts. In agreement with these results, we found that CD4 and the associated Lck t... |
11799153 | Properties of the surface envelope glycoprotein associated with virulence of simian-human immunodeficiency virus SHIV(SF33A) molecular clones. | In vivo adaptation of simian-human immunodeficiency virus (SHIV) clone SHIV(SF33) resulted in the emergence of pathogenic isolate SHIV(SF33A), which caused a rapid and severe CD4(+) T-cell depletion when inoculated into rhesus macaques. Two molecular clones generated by inserting the env V1-to-V5 region amplified from ... |
11799137 | Caveolae and cholesterol distribution in vascular smooth muscle cells of different phenotypes. | Vascular smooth muscle cells (SMCs) grown in primary culture are converted from a contractile to a synthetic phenotype. This includes a marked morphological reorganization, with loss of myofilaments and formation of a large ER-Golgi complex. In addition, the number of cell surface caveolae is distinctly reduced and the... |
11796764 | Protein aggregates and dementia: is there a common toxicity? | This review considers some of the recent advances made in the understanding of the pathogenic proteins known to aggregate and be implicated in neurodegenerative dementing disorders. It concentrates on the two most obvious candidates for the role of toxic protein in Alzheimer's disease (AD)--beta-amyloid peptide and tau... |
11796583 | Porins from Salmonella enterica serovar Typhimurium activate the transcription factors activating protein 1 and NF-kappaB through the Raf-1-mitogen-activated protein kinase cascade. | In this study we examined the ability of Salmonella enterica serovar Typhimurium porins to activate activating protein 1 (AP-1) and nuclear factor kappaB (NF-kappaB) through the mitogen-activated protein kinase (MAPK) cascade, and we identified the AP-1-induced protein subunits. Our results demonstrate that these enzym... |
11796335 | Strong antifungal activity of SS750, a new triazole derivative, is based on its selective binding affinity to cytochrome P450 of fungi. | SS750 [(R)-(-)-2-(2,4-difluorophenyl)-1-(ethylsulfonyl)-1,1-difluoro-3-(1H-1,2,4-triazol-1-yl)-2-propanol] is a new triazole, and its potential as an antifungal agent was evaluated by in vitro and in vivo studies. In a comparison of the MICs at which 50% of isolates are inhibited (MIC(50)s) for all strains of Candida s... |
11790842 | Side-chain modeling with an optimized scoring function. | Modeling side-chain conformations on a fixed protein backbone has a wide application in structure prediction and molecular design. Each effort in this field requires decisions about a rotamer set, scoring function, and search strategy. We have developed a new and simple scoring function, which operates on side-chain ro... |
11790838 | Soft protein-protein docking in internal coordinates. | The association of two biological macromolecules is a fundamental biological phenomenon and an unsolved theoretical problem. Docking methods for ab initio prediction of association of two independently determined protein structures usually fail when they are applied to a large set of complexes, mostly because of inaccu... |
11790836 | Crystal structure of the collagen triple helix model [(Pro-Pro-Gly)(10)](3). | The first report of the full-length structure of the collagen-like polypeptide [(Pro-Pro-Gly)(10)](3) is given. This structure was obtained from crystals grown in a microgravity environment, which diffracted up to 1.3 A, using synchrotron radiation. The final model, which was refined to an R(factor) of 0.18, is the hig... |
11790828 | Multiple diverse ligands binding at a single protein site: a matter of pre-existing populations. | Here, we comment on the steadily increasing body of data showing that proteins with specificity actually bind ligands of diverse shapes, sizes, and composition. Such a phenomenon is not surprising when one considers that binding is a dynamic process with populations in equilibrium and that the shape of the binding site... |
11790748 | Characterization of an archaeal cyclodextrin glucanotransferase with a novel C-terminal domain. | A gene encoding a cyclodextrin glucanotransferase (CGTase) from Thermococcus kodakaraensis KOD1 (CGT(Tk)) was identified and characterized. The gene (cgt(Tk)) encoded a protein of 713 amino acid residues harboring the four conserved regions found in all members of the alpha-amylase family. However, the C-terminal domai... |
11790740 | Identification of the periplasmic cobalamin-binding protein BtuF of Escherichia coli. | Cells of Escherichia coli take up vitamin B(12) (cyano-cobalamin [CN-Cbl]) and iron chelates by use of sequential active transport processes. Transport of CN-Cbl across the outer membrane and its accumulation in the periplasm is mediated by the TonB-dependent transporter BtuB. Transport across the cytoplasmic membrane ... |
11753933 | Why do crown ethers activate enzymes in organic solvents? | One of the major drawbacks of enzymes in nonaqueous solvents is that their activity is often dramatically low compared to that in water. This limitation can be largely overcome by crown ether treatment of enzymes. In this paper, we describe a number of carefully designed new experiments that have improved the insights ... |
11981679 | Revision of the multiple organ failure score. | <h4>Background and aim</h4>The multiple organ failure (MOF) score published by Goris et al. in 1985 was one of the first attempts to quantify severity of organ dysfunction and failure based on expert opinion in surgical intensive care unit patients. Fifteen years later a reassessment of this score is mandatory.<h4>Pati... |
11828130 | 2-(4-Bromophenyl)-1,2-dihydropyrimido[1,2-a]benzimidazol-4(3H)-one and 4-(4-methylphenyl)-3,4-dihydropyrimido[1,2-a]benzimidazol-2(1H)-one form hydrogen-bonded base-paired dimers. | The title compounds, 2-(4-bromophenyl)-1,2-dihydropyrimido[1,2-a]benzimidazol-4-(3H)-one, C(16)H(12)BrN(3)O, (IVa), and 4-(4-methylphenyl)-3,4-dihydropyrimido[1,2-a]benzimidazol-2-(1H)-one, C(17)H(15)N(3)O, (Vb), both form R(2)(2)(8) centrosymmetric dimers via N-H...N hydrogen bonds. The N...N distance is 2.943(3)A for... |
11818332 | An essential role for membrane rafts in the initiation of Fas/CD95-triggered cell death in mouse thymocytes. | Fas, a member of the tumor necrosis factor receptor family, can upon ligation by its ligand or agonistic antibodies trigger signaling cascades leading to cell death in lymphocytes and other cell types. Such signaling cascades are initiated through the formation of a membrane death-inducing signaling complex (DISC) that... |
11818575 | Coherent infrared emission from myoglobin crystals: an electric field measurement. | We introduce coherent infrared emission interferometry as a chi(2) vibrational spectroscopy technique and apply it to studying the initial dynamics upon photoactivation of myoglobin (Mb). By impulsive excitation (using 11-fs pulses) of a Mb crystal, vibrations that couple to the optical excitation are set in motion coh... |
11846887 | The mechanisms responsible for 2-dimensional pattern formation in bacterial macrofiber populations grown on solid surfaces: fiber joining and the creation of exclusion zones. | <h4>Background</h4>When Bacillus subtilis is cultured in a complex fluid medium under conditions where cell separation is suppressed, populations of multicellular macrofibers arise that mature into ball-like structures. The final sedentary forms are found distributed in patterns on the floor of the growth chamber altho... |
11815625 | Cytokine signaling: STATS in plasma membrane rafts. | STAT transcription factors signal from the plasma membrane to the nucleus in response to growth factors and cytokines. We have investigated whether plasma membrane "rafts" are involved in cytokine-activated STAT signaling. Cytokine-free human hepatoma Hep3B cells or cells treated with interleukin-6 (IL-6) or orthovanad... |
11815635 | Acyl-CoA oxidase is imported as a heteropentameric, cofactor-containing complex into peroxisomes of Yarrowia lipolytica. | Five isoforms of acyl-CoA oxidase (Aox), designated Aox1p to Aox5p, constitute a 443-kD heteropentameric complex containing one polypeptide chain of each isoform within the peroxisomal matrix of the yeast Yarrowia lipolytica. Assembly of the Aox complex occurs in the cytosol and precedes its import into peroxisomes. Pe... |
11815633 | A fluorescent resonant energy transfer-based biosensor reveals transient and regional myosin light chain kinase activation in lamella and cleavage furrows. | Approaches with high spatial and temporal resolution are required to understand the regulation of nonmuscle myosin II in vivo. Using fluorescence resonance energy transfer we have produced a novel biosensor allowing simultaneous determination of myosin light chain kinase (MLCK) localization and its [Ca2+]4/calmodulin-b... |
11815630 | The importin-beta binding domain of snurportin1 is responsible for the Ran- and energy-independent nuclear import of spliceosomal U snRNPs in vitro. | The nuclear localization signal (NLS) of spliceosomal U snRNPs is composed of the U snRNA's 2,2,7-trimethyl-guanosine (m3G)-cap and the Sm core domain. The m3G-cap is specifically bound by snurportin1, which contains an NH2-terminal importin-beta binding (IBB) domain and a COOH-terminal m3G-cap--binding region that bea... |
12806052 | Structural predestination of individual diversity in the course and severity of infectious diseases. | Infectious diseases can be manifested by a spectrum of clinical signs and resultant clinical courses that range from acute to chronic and possible persistence in the victim in a latent form. Until recently, the origins of this kind of biodiversity were poorly understood, but advances in immunology--especially in identi... |
11863828 | Field-dependent anisotropy change in a supramolecular Mn(II)- [3 x 3] grid. | The magnetic anisotropy of a novel Mn(II)- [3x3] grid complex was investigated by means of high-field torque magnetometry. Torque vs field curves at low temperatures demonstrates a ground state with S>0 and exhibits a torque step due to a field-induced level crossing at B(*) approximately 7.5 T, accompanied by an abrup... |
11828123 | Supramolecular hydrogen-bonded hexamers in two 5-aryl-3-methyl-1-phenyl-1,6,7,8-tetrahydropyrazolo[3,4-b][1,4]diazepines. | In both title compounds, i.e. 3-methyl-1,5-diphenyl-1,6,7,8-tetrahydropyrazolo[3,4-b][1,4]diazepine, C(19)H(18)N(4), (I), and 5-(4-chlorophenyl)-3-methyl-1-phenyl-1,6,7,8-tetrahydropyrazolo[3,4-b][1,4]diazepine, C(19)H(17)ClN(4), (II), an N-H...N hydrogen bond links six molecules to form an R(6)(6)(30) ring. Compound (... |
11828099 | [(1,4,8,11-Tetraazacyclotetradeca-1,4,8,11-tetrayl)tetraacetamide-kappa6N1,N4,N8,N11,O1,O8]copper(II) sulfate 4.5-hydrate. | The crystal structure of the title copper(II) complex, [Cu(C(18)H(36)N(8)O(4))]SO(4).4.5H(2)O, formed with the tetraamide cyclam derivative 2-(4,8,11-triscarbamoylmethyl-1,4,8,11-tetraazacyclotetradec-1-yl)acetamide (TETAM), is described. The macrocycle lies on an inversion centre occupied by the hexacoordinated Cu ato... |
11805290 | Type I collagen is thermally unstable at body temperature. | Measured by ultra-slow scanning calorimetry and isothermal circular dichroism, human lung collagen monomers denature at 37 degrees C within a couple of days. Their unfolding rate decreases exponentially at lower temperature, but complete unfolding is observed even below 36 degrees C. Refolding of full-length, native co... |
11807098 | Different splice variants of filamin-B affect myogenesis, subcellular distribution, and determine binding to integrin [beta] subunits. | Integrins connect the extracellular matrix with the cell interior, and transduce signals through interactions of their cytoplasmic tails with cytoskeletal and signaling proteins. Using the yeast two-hybrid system, we isolated a novel splice variant (filamin-Bvar-1) of the filamentous actin cross-linking protein, filami... |
11863551 | Disorder and funneling effects on exciton migration in treelike dendrimers. | The center-bound excitonic diffusion on dendrimers subjected to several types of nonhomogeneous funneling potentials is considered. We first study the mean first passage time (MFPT) for diffusion in a linear potential with different types of correlated and uncorrelated random perturbations. Increasing the funneling for... |
11828088 | First- and second- sphere coordination of the uranyl ion by bis[2-(2-hydroxyphenoxy)ethoxy]ethane. | Uranyl nitrate hexahydrate reacts with bis[2-(2-hydroxyphenoxy)ethoxy]ethane (C(18)H(22)O(6)), denoted LH(2) hereafter, in the presence of triethylamine to give triethylammonium aqua[2,2'-(3,6-dioxaoctane-1,8-diyldioxy)diphenolato-kappa(2)O,O'](nitrato-kappa(2)O,O')dioxouranium(VI), (Et(3)NH)[UO(2)(H(2)O)L(NO(3))], whi... |
11792838 | A stochastic algorithm for global optimization and for best populations: a test case of side chains in proteins. | The problem of global optimization is pivotal in a variety of scientific fields. Here, we present a robust stochastic search method that is able to find the global minimum for a given cost function, as well as, in most cases, any number of best solutions for very large combinatorial "explosive" systems. The algorithm i... |
11792829 | Self-assembly properties of a model RING domain. | RING domains act in a variety of essential cellular processes but have no general function ascribed to them. Here, we observe that purified arenaviral protein Z, constituted almost entirely by its RING domain, self-assembles in vitro into spherical structures that resemble functional bodies formed by Z in infected cell... |
11781337 | Smitin, a novel smooth muscle titin-like protein, interacts with myosin filaments in vivo and in vitro. | Smooth muscle cells use an actin-myosin II-based contractile apparatus to produce force for a variety of physiological functions, including blood pressure regulation and gut peristalsis. The organization of the smooth muscle contractile apparatus resembles that of striated skeletal and cardiac muscle, but remains much ... |
11773627 | Directed molecular evolution of ADP-glucose pyrophosphorylase. | ADP-glucose pyrophosphorylase catalyzes a rate-limiting reaction in prokaryotic glycogen and plant starch biosynthesis. Despite sharing similar molecular size and catalytic and allosteric regulatory properties, the prokaryotic and higher plant enzymes differ in higher-order protein structure. The bacterial enzyme is en... |
11773621 | The glycosynapse. | Physically distinguishable microdomains associated with various functional membrane proteins are one of the major current topics in cell biology. Glycosphingolipids present in such microdomains have been used as "markers;" however, the functional role of glycosyl epitopes in microdomains has received little attention. ... |
32214771 | Targeting and expression of antigenic proteins in transgenic plants for production of edible oral vaccines. | Exploiting plants as biological bioreactors for production and delivery of edible oral subunit vaccines is a promising application of biotechnology. Efforts to enhance expression levels of transgenes coding for antigenic proteins by exploiting promoters, targeting sequences, and enhancer elements have produced rather l... |
30449904 | Stereoselective Synthesis of the C<sub>11</sub>-N<sub>26</sub> Fragment of Griseoviridin. | The C<sub>11</sub>-N<sub>26</sub> fragment of griseoviridin has been prepared enantioselectively. The 1,3-<i>syn</i> diol synthon was derived from lipase-catalyzed selective acylation of(±)-1-(benzyloxy)pent-4-en-2-ol. The conjugated (<i>E</i>,<i>E</i>)-dienylmethyl azide functionality was installed by a Pd-catalyzed a... |
18924742 | Integrated luminometer for the determination of trace metals in seawater using fluorescence, phosphorescence and chemiluminescence detection. | The paper describes an integrated luminometer able to perform fluorescence (FL), room temperature phosphorescence (RTP) and chemiluminescence (CL) measurements on seawater samples. The technical details of the instrumentation are presented together with flow injection (FI) manifolds for the determination of cadmium and... |
18475426 | Facile Synthesis of cis-Dichloro-(1,4,7-Triazacyclononane) Platinum(II) and its Screening Against Human Ovarian Cancer (SK-OV-3) and Leukemia (K-562) Cell Lines. | A simple method for the preparation of cis-dichloro(1,4,7-triazacyclononane)platinum(II), cis-Pt(tacn)Cl(2) is presented, together with the results of screening the compound against the K-562 (leukemia) and SK-OV-3 (ovarian) human cancer cell lines. While the compound shows no activity against K-562 cells, there is evi... |
18475421 | Development of Functional Models for a SOD. | Superoxide dismutase (SOD) is the scavenger of superoxide anion (O2(-)) and functions as a protector of living bodies. Study of a model compound of SOD is important when searching for the relationship between functions and structures of enzymes. Furthermore, SOD model compounds have potential for therapeutic usefulness... |
18476017 | Antimicrobial, Antifertility and Antiinflammatory Approach to Tetradentate Macrocyclic Complexes of Iron(II) and Manganese(II). | Some antifertility inhibitors of 18 to 24-membered tetraazamacrocyclic complexes of iron(II) and manganese(II) have been synthesised by the template condensation using 1,3-phenylenediamine with malonic acid, succinic acid, glutaric acid and adipic acid. The reaction proceed smoothly to completion. The complexes were ch... |
18476012 | Txicological Aspects of Newly Designed Macrocyclic Complexes of Iron(II). | Brine shrimp lethality of a new series of 16 to 26-membered macrocycles of iron(II) containing tetraaza groups and prepared by the template condensation reaction of diacarboxylic acids (malonic, succinic, glutaric or adipic) with 2,6-diaminopyridine and diethylenetriamine in 1:2:2 molar ratios have been studied. Struct... |
16985646 | The future of bladder control-intravesical drug delivery, a pinch of pepper, and gene therapy. | The incidence of urinary incontinence and overactive bladder problems will continue to grow as the population ages. Future treatments are likely to include an implantable drug delivery system, gene therapy, and the intravesical use of the vallinoids capsaicin and resiniferatoxin (RTX). An understanding of the urotheliu... |
16290351 | Molecular recognition of avidin on biotin-functionalized gold surfaces detected by FT-IRRAS and use of metal carbonyl probes. | Fourier transform infrared reflection-absorption spectroscopy (FT-IRRAS) was successively used to monitor the covalent immobilization of biotin molecules onto a planar gold substrate covered with a self-assembled monolayer of cystamine and to transduce the molecular recognition of avidin and biotin. This detection was ... |
16245108 | Membrane biogenesis in anoxygenic photosynthetic prokaryotes. | Following the discovery of photosynthetic bacteria in the nineteenth century, technical developments of the 1950s led to their use in membrane biogenesis studies. These investigations had their origins in the isolation of subcellular particles designated as 'chromatophores' by Roger Stanier and colleagues, which were s... |
16233280 | Enzymatic synthesis of l-menthyl alpha-maltoside and l-menthyl alpha-maltooligosides from l-menthyl alpha-glucoside by cyclodextrin glucanotransferase. | l-Menthyl alpha-D-glucopyranosyl-(1-->4)-alpha-d-glucopyranoside (alpha-MenG2), a novel glycoside of l-menthol, was synthesized enzymatically and its physicochemical properties were characterized. Production of alpha-MenG2 from l-menthyl alpha-d-glucopyranoside (alpha-MenG) was attempted since we had already succeeded ... |
16228541 | Which side of the pi-macrocycle plane of (bacterio)chlorophylls is favored for binding of the fifth ligand? | Reported crystallographic data and calculated molecular models indicated that chlorophyll (Chl) a and bacteriochlorophyll (BChl) a tend to bind the fifth ligand on the side of the macrocycle where the C13(2)-(R)-methoxycarbonyl moiety protrudes (denoting the 'back' side). The crystal structures of 34 photosynthetic pro... |
14720074 | Delivery systems for pulmonary gene therapy. | Delivery of therapeutic genes to the lungs is an attractive strategy to correct a variety of pulmonary dysfunctions such as cystic fibrosis, alpha-1 antitrypsin deficiency, pulmonary hypertension, asthma, and lung cancer. Different delivery routes such as intratracheal instillation, aerosol and intravenous injection ha... |
14646042 | Intravital fluorescence facilitates measurement of multiple physiologic functions and gene expression in tumors of live animals. | The purpose of this report is to present an overview of the use of fluorescence imaging in vivo, with particular emphasis on oncology. It is important to note, however, that many of the methods described herein have been applied to the study of non-malignant tissues as well. Modern medicine and biology research has ben... |
12952069 | Signaling pathways regulating Dictyostelium myosin II. | Dictyostelium myosin II is a conventional, two-headed myosin that consists of two copies each of a myosin heavy chain (MHC), an essential light chain (ELC) and a regulatory light chain (RLC). The MHC is comprised of an amino-terminal motor domain, a neck region that binds the RLC and ELC and a carboxyl-terminal alpha-h... |
12952063 | Dynamic organization of the actin system in the motile cells of Dictyostelium. | The actin system forms a supramolecular, membrane-associated network that serves multiple functions in Dictyostelium cells, including cell motility controlled by chemoattractant, phagocytosis, macropinocytosis, and cytokinesis. In executing these functions the monomeric G-actin polymerizes reversibly, and the actin fil... |
12916923 | Crystal doping aided by rapid expansion of supercritical solutions. | The purpose of this study was to test the utility of rapid expansion of supercritical solution (RESS) based cocrystallizations in inducing polymorph conversion and crystal disruption of chlorpropamide (CPD). CPD crystals were recrystallized by the RESS process utilizing supercritical carbon dioxide as the solvent. The ... |
12916941 | Intercalation compounds of hydrotalcite-like anionic clays with anti-inflammatory agents, II: Uptake of diclofenac for a controlled release formulation. | The purpose of this study was to investigate whether hydrotalcite is able to intercalate diclofenac, a nonsteroidal anti-inflammatory drug, and release it in a controlled manner. Layered Mg-Al hydrotalcite in the chloride form was used as a host, and the intercalation compound was prepared by Cl-/diclofenac anionic exc... |
12916933 | Preparation of budesonide and budesonide-PLA microparticles using supercritical fluid precipitation technology. | The objective of this study was to prepare and characterize microparticles of budesonide alone and budesonide and polylactic acid (PLA) using supercritical fluid (SCF) technology. A precipitation with a compressed antisolvent (PCA) technique employing supercritical CO2 and a nozzle with 100- microm internal diameter wa... |
12916950 | Essential oil formulations useful as a new tool for insect pest control. | This study investigated the effects of some essential oils on Limantria dispar (Lepidoptera: Lymantridae, gypsy moth) larvae, one of the most serious pests of cork oak forests. The essential oils were first formulated as oil in water (o/w) emulsions and used in laboratory bioassays to assess their lethal concentration ... |
12916956 | Response surface methodology for the optimization of ubiquinone self-nanoemulsified drug delivery system. | The aim of the present study was to prepare and evaluate an optimized, self-nanoemulsified drug delivery system of ubiquinone. A 3-factor, 3-level Box-Behnken design was used for the optimization procedure with the amounts of Polyoxyl 35 castor oil (X1), medium-chain mono- and diglyceride (X2), and lemon oil (X3) as th... |
12903215 | DNA topology: topological transformation of DNA by reaction of cisplatin-DNA-core histone complexes with human DNA topoisomerase. | Cis-diamminedichloroplatinium(II), an active antitumor agent binds to core-histone -SV40 DNA complexes prepared by reaction of DNA with core-histone, and alters the fiber-like structure into the loosened structure. In order to model the cisplatin-modified chromatin complexes in cell, the complexes were reacted with hum... |
12903181 | Synthesis of adamantyl naphthalene diimide and its interaction with double stranded DNA. | An adamantyl naphthalene diimide derivative (AND) was synthesized as a highly selective double stranded DNA binding reagent. The binding studies with sonicated calf thymus DNA revealed that AND can bind to double stranded DNA by the threading mode, where the two adamantyl moieties are located in the major and minor gro... |
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