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Sample records for acyl groups separated

  1. Preparation of Polybutylene Oxides Bearing Terminal Ester Groups by Treatment of H[(CH_2)_4O]_nSiR_3 with Acyl Halides

    OpenAIRE

    Iura, Takafumi; Matsubara, Kouki; Nagashima,Hideo

    2000-01-01

    Treatment of H[(CH_2)_4O]_nSiR_3, which were prepared by the silane induced polymerization of THF with acyl halides catalyzed by (μ_3:η^2:η^3:η^5-acenaphthylene)Ru_3(CO)_7, provides a novel synthetic method for polybutylene oxides bearing terminal ester groups. Various acyl halides such as acetyl chloride, benzoyl bromide, adipoyl chloride, acryloyl chloride, and 2-bromoisobutyryl bromide could be used as the acyl halide component; the reactivity of acyl halides increased in the order RCOBr>R...

  2. The Enantiomer Separations of Allethrone and Propargyllone Using Two Long Chain Acylated β-Cyclodextrin Derivatives as CGC Capillary Stationary Phases

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Using two β-cyclodextrin derivatives (CDs) with long chain of acyl groups as chiral stationary phases (CSPs) of capillary gas chromatography (CGC), the enantiomers of racemic allethrone and propargyllone were well resolved after derived with acetyl chloride. The enantiomer excess values (e.e.%) of 1S-allethrone and 1S-propargyllone were also determined successfully using these CDs.

  3. Separation of isomeric short-chain acyl-CoAs in plant matrices using ultra-performance liquid chromatography coupled with tandem mass spectrometry.

    Science.gov (United States)

    Purves, Randy W; Ambrose, Stephen J; Clark, Shawn M; Stout, Jake M; Page, Jonathan E

    2015-02-01

    Acyl coenzyme A (acyl-CoA) thioesters are important intermediates in cellular metabolism and being able to distinguish among them is critical to fully understanding metabolic pathways in plants. Although significant advances have been made in the identification and quantification of acyl-CoAs using liquid chromatography tandem mass spectrometry (LC-MS/MS), separation of isomeric species such as isobutyryl- and n-butyrl-CoA has remained elusive. Here we report an ultra-performance liquid chromatography (UPLC)-MS/MS method for quantifying short-chain acyl-CoAs including isomeric species n-butyryl-CoA and isobutyryl-CoA as well as n-valeryl-CoA and isovaleryl-CoA. The method was applied to the analysis of extracts of hop (Humulus lupulus) and provided strong evidence for the existence of an additional structural isomer of valeryl-CoA, 2-methylbutyryl-CoA, as well as an unexpected isomer of hexanoyl-CoA. The results showed differences in the acyl-CoA composition among varieties of Humulus lupulus, both in glandular trichomes and cone tissues. When compared with the analysis of hemp (Cannabis sativa) extracts, the contribution of isobutyryl-CoAs in hop was greater as would be expected based on the downstream polyketide products. Surprisingly, branched chain valeryl-CoAs (isovaleryl-CoA and 2-methylbutyryl-CoA) were the dominant form of valeryl-CoAs in both hop and hemp. The capability to separate these isomeric forms will help to understand biochemical pathways leading to specialized metabolites in plants.

  4. Acyl-coenzyme A binding protein (ACBP)

    DEFF Research Database (Denmark)

    Kragelund, B B; Knudsen, J; Poulsen, F M

    1999-01-01

    Acyl-coenzyme A binding proteins are known from a large group of eukaryote species and to bind a long chain length acyl-CoA ester with very high affinity. Detailed biochemical mapping of ligand binding properties has been obtained as well as in-depth structural studies on the bovine apo-protein...... and of the complex with palmitoyl-CoA using NMR spectroscopy. In the four alpha-helix bundle structure, a set of 21 highly conserved residues present in more that 90% of all known sequences of acyl-coenzyme A binding proteins constitutes three separate mini-cores. These residues are predominantly located...... at the helix-helix interfaces. From studies of a large set of mutant proteins the role of the conserved residues has been related to structure, function, folding and stability....

  5. Acyl-coenzyme A binding protein, ACBP

    DEFF Research Database (Denmark)

    Kragelund, Birthe Brandt; Knudsen, J.; Poulsen, Flemming

    1999-01-01

    Acyl-coenzyme A binding proteins are known from a large group of eukaryote species and to bind a long chain length acyl-CoA ester with very high affinity. Detailed biochemical mapping of ligand binding properties has been obtained as well as in-depth structural studies on the bovine apo-protein...... and of the complex with palmitoyl-CoA using NMR spectroscopy. In the four a-helix bundle structure, a set of 21 highly conserved residues present in more that 90% of all known sequences of acyl-coenzyme A binding proteins constitutes three separate mini-cores. These residues are predominantly located at the helix......-helix interfaces. From studies of a large set of mutant proteins the role of the conserved residues has been related to structure, function, folding and stability....

  6. Stability-increasing effects of anthocyanin glycosyl acylation.

    Science.gov (United States)

    Zhao, Chang-Ling; Yu, Yu-Qi; Chen, Zhong-Jian; Wen, Guo-Song; Wei, Fu-Gang; Zheng, Quan; Wang, Chong-De; Xiao, Xing-Lei

    2017-01-01

    This review comprehensively summarizes the existing knowledge regarding the chemical implications of anthocyanin glycosyl acylation, the effects of acylation on the stability of acylated anthocyanins and the corresponding mechanisms. Anthocyanin glycosyl acylation commonly refers to the phenomenon in which the hydroxyl groups of anthocyanin glycosyls are esterified by aliphatic or aromatic acids, which is synthetically represented by the acylation sites as well as the types and numbers of acyl groups. Generally, glycosyl acylation increases the in vitro and in vivo chemical stability of acylated anthocyanins, and the mechanisms primarily involve physicochemical, stereochemical, photochemical, biochemical or environmental aspects under specific conditions. Additionally, the acylation sites as well as the types and numbers of acyl groups influence the stability of acylated anthocyanins to different degrees. This review could provide insight into the optimization of the stability of anthocyanins as well as the application of suitable anthocyanins in food, pharmaceutical and cosmetic industries. PMID:27507456

  7. Acylation of Antioxidant of Bamboo Leaves with Fatty Acids by Lipase and the Acylated Derivatives' Efficiency in the Inhibition of Acrylamide Formation in Fried Potato Crisps.

    Directory of Open Access Journals (Sweden)

    Xiang Ma

    Full Text Available This study selectively acylated the primary hydroxyl groups on flavonoids in antioxidant of bamboo leaves (AOB using lauric acid with Candida antarctica lipase B in tert-amyl-alcohol. The separation and isolation of acylated derivatives were performed using silica gel column chromatography with a mixture of dichloromethane/diethyl ether/methanol as eluents. Both thin layer chromatography and high-performance liquid chromatography analyses confirmed the high efficiency of the isolation process with the purified orientin-6″-laurate, isoorientin-6″-laurate, vitexin-6″-laurate, and isovitexin-6″-laurate that were obtained. The addition of AOB and acylated AOB reduced acrylamide formation in fried potato crisps. Results showed that 0.05% AOB and 0.05% and 0.1% acylated AOB groups significantly (p < 0.05 reduced the content of acrylamide in potato crisps by 30.7%, 44.5%, and 46.9%, respectively.

  8. Intramolecular coupling of eta/sup 2/-iminoacyl and eta/sup 2/-acyl functions at group 4 and group 5 metal centers: structure and spectroscopic properties of the resulting enamidolate and enediamide complexes

    Energy Technology Data Exchange (ETDEWEB)

    Chamberlain, L.R.; Durfee, L.D.; Fanwick, P.E.; Kobriger, L.M.; Latesky, S.L.; McMullen, A.K.; Steffey, B.D.; Rothwell, I.P.; Folting, K.; Huffman, J.C.

    1987-09-30

    During their studies of the early d-block metal chemistry associated with aryloxide ligation they have examined the reactivity of a series of mixed alkyl, aryloxide compounds toward CO and the isoelectronic organic isocyanide molecule. This has allowed them to isolate and study in detail a series of compounds containing a number of eta/sup 2/-iminoacyl functions. Furthermore they have demonstrated that intramolecular coupling of iminoacyl groups to produce enediamido ligands can take place, as well as the related coupling of iminoacyl and acyl groups. They report here in detail the synthesis of a number of enamidolate and enediamido complexes using this synthetic method and also report in detail on the coordination properties of the resulting metallacycles, an area that has received recent theoretical interest. In a subsequent paper they report a kinetic investigation of these carbon-carbon bond-forming processes.

  9. Interaction of bovine serum albumin with N-acyl amino acid based anionic surfactants: Effect of head-group hydrophobicity.

    Science.gov (United States)

    Ghosh, Subhajit; Dey, Joykrishna

    2015-11-15

    The function of a protein depends upon its structure and surfactant molecules are known to alter protein structure. For this reason protein-surfactant interaction is important in biological, pharmaceutical, and cosmetic industries. In the present work, interactions of a series of anionic surfactants having the same hydrocarbon chain length, but different amino acid head group, such as l-alanine, l-valine, l-leucine, and l-phenylalanine with the transport protein, bovine serum albumin (BSA), were studied at low surfactant concentrations using fluorescence and circular dichroism (CD) spectroscopy, and isothermal titration calorimetry (ITC). The results of fluorescence measurements suggest that the surfactant molecules bind simultaneously to the drug binding site I and II of the protein subdomain IIA and IIIA, respectively. The fluorescence as well as CD spectra suggest that the conformation of BSA goes to a more structured state upon surfactant binding at low concentrations. The binding constants of the surfactants were determined by the use of fluorescence as well as ITC measurements and were compared with that of the corresponding glycine-derived surfactant. The binding constant values clearly indicate a significant head-group effect on the BSA-surfactant interaction and the interaction is mainly hydrophobic in nature.

  10. Calcium-myristoyl Tug is a new mechanism for intramolecular tuning of calcium sensitivity and target enzyme interaction for guanylyl cyclase-activating protein 1: dynamic connection between N-fatty acyl group and EF-hand controls calcium sensitivity.

    Science.gov (United States)

    Peshenko, Igor V; Olshevskaya, Elena V; Lim, Sunghyuk; Ames, James B; Dizhoor, Alexander M

    2012-04-20

    Guanylyl cyclase-activating protein 1 (GCAP1), a myristoylated Ca(2+) sensor in vision, regulates retinal guanylyl cyclase (RetGC). We show that protein-myristoyl group interactions control Ca(2+) sensitivity, apparent affinity for RetGC, and maximal level of cyclase activation. Mutating residues near the myristoyl moiety affected the affinity of Ca(2+) binding to EF-hand 4. Inserting Phe residues in the cavity around the myristoyl group increased both the affinity of GCAP1 for RetGC and maximal activation of the cyclase. NMR spectra show that the myristoyl group in the L80F/L176F/V180F mutant remained sequestered inside GCAP1 in both Ca(2+)-bound and Mg(2+)-bound states. This mutant displayed much higher affinity for the cyclase but reduced Ca(2+) sensitivity of the cyclase regulation. The L176F substitution improved affinity of myristoylated and non-acylated GCAP1 for the cyclase but simultaneously reduced the affinity of Ca(2+) binding to EF-hand 4 and Ca(2+) sensitivity of the cyclase regulation by acylated GCAP1. The replacement of amino acids near both ends of the myristoyl moiety (Leu(80) and Val(180)) minimally affected regulatory properties of GCAP1. N-Lauryl- and N-myristoyl-GCAP1 activated RetGC in a similar fashion. Thus, protein interactions with the central region of the fatty acyl chain optimize GCAP1 binding to RetGC and maximize activation of the cyclase. We propose a dynamic connection (or "tug") between the fatty acyl group and EF-hand 4 via the C-terminal helix that attenuates the efficiency of RetGC activation in exchange for optimal Ca(2+) sensitivity. PMID:22383530

  11. Site-Selective Acylations with Tailor-Made Catalysts.

    Science.gov (United States)

    Huber, Florian; Kirsch, Stefan F

    2016-04-18

    The acylation of alcohols catalyzed by N,N-dimethylamino pyridine (DMAP) is, despite its widespread use, sometimes confronted with substrate-specific problems: For example, target compounds with multiple hydroxy groups may show insufficient selectivity for one hydroxyl, and the resulting product mixtures are hardly separable. Here we describe a concept that aims at tailor-made catalysts for the site-specific acylation. To this end, we introduce a catalyst library where each entry is constructed by connecting a variable and readily tuned peptide scaffold with a catalytically active unit based on DMAP. For selected examples, we demonstrate how library screening leads to the identification of optimized catalysts, and the substrates of interest can be converted with a markedly enhanced site-selectivity compared with only DMAP. Furthermore, substrate-optimized catalysts of this type can be used to selectively convert "their" substrate in the presence of structurally similar compounds, an important requisite for reactions with mixtures of substances. PMID:26970553

  12. Sulfide precipitation method of separating uranium from group II and group III metal ions

    International Nuclear Information System (INIS)

    Uranium is separated from analytical Group II and Group III metal ions in an aqueous liquor containing uranyl ions. The liquor is extracted with a non-interfering, water-immiscible, organic solvent containing a reagent which will react with the uranyl ions to form a complex soluble in the solvent. If the liquor is acidic, the solvent is washed with water. Then to the solvent is added an aqueous solution containing about 0.5 to 1.0 mole per liter of (NH4)2CO3 or NH4HCO3 ions and sufficient sulfide ions to precipitate the metal ions as sulfides. The solvent and the aqueous solution are separated and the sulfides filtered from the aqueous solution. The ammonium-uranyl-tricarbonate in the aqueous solution can then be precipitated by increasing the concentration of (NH4)2CO3 or NH4HCO3 ions to about 1.5 to 2.5 moles per liter. The precipitate is filtered and calcined to obtain U3O8 or UO2. (author)

  13. Oxidative acylation using thioacids

    Science.gov (United States)

    Liu, R.; Orgel, L. E.

    1997-01-01

    Several important prebiotic reactions, including the coupling of amino acids into polypeptides by the formation of amide linkages, involve acylation. Theae reactions present a challenge to the understanding of prebiotic synthesis. Condensation reactions relying on dehydrating agents are either inefficient in aqueous solution or require strongly acidic conditions and high temperatures. Activated amino acids such as thioester derivatives have therefore been suggested as likely substrates for prebiotic peptide synthesis. Here we propose a closely related route to amide bond formation involving oxidative acylation by thioacids. We find that phenylalanine, leucine and phenylphosphate are acylated efficiently in aqueous solution by thioacetic acid and an oxidizing agent. From a prebiotic point of view, oxidative acylation has the advantage of proceeding efficiently in solution and under mild conditions. We anticipate that oxidative acylation should prove to be a general method for activating carboxylic acids, including amino acids.

  14. Group Foliation Method and Functional Separation of Variables to Nonlinear Diffusion Equations

    Institute of Scientific and Technical Information of China (English)

    QU Chang-Zheng; ZHANG Shun-Li

    2005-01-01

    @@ Generalized functional separation of variables to nonlinear diffusion equations is studied in terms of the extended group foliation method. A complete classification for the nonlinear diffusion equation with source term which admits functional separable solutions is presented.

  15. Selective acylation of primary amines in peptides and proteins

    NARCIS (Netherlands)

    Abello, N.; Kerstjens, H.A.M.; Postma, D.S; Bischoff, Rainer

    2007-01-01

    N-hydroxysuccinimide (NHS) esters are derivatizing agents that target primary amine groups. However, even a small molar excess of NHS may lead to acylation of hydroxyl-containing amino acids as a side reaction. We report a straightforward method for the selective removal of ester-linked acyl groups

  16. Characterization of the "Escherichia Coli" Acyl Carrier Protein Phosphodiesterase

    Science.gov (United States)

    Thomas, Jacob

    2009-01-01

    Acyl carrier protein (ACP) is a small essential protein that functions as a carrier of the acyl intermediates of fatty acid synthesis. ACP requires the posttranslational attachment of a 4'phosphopantetheine functional group, derived from CoA, in order to perform its metabolic function. A Mn[superscript 2+] dependent enzymatic activity that removes…

  17. Enzymatic acylation of starch.

    Science.gov (United States)

    Alissandratos, Apostolos; Halling, Peter J

    2012-07-01

    Starch a cheap, abundant and renewable natural material has been chemically modified for many years. The popular modification acylation has been used to adjust rheological properties as well as deliver polymers with internal plasticizers and other potential uses. However the harsh reaction conditions required to produce these esters may limit their use, especially in sensitive applications (foods, pharmaceuticals, etc.). The use of enzymes to catalyse acylation may provide a suitable alternative due to high selectivities and mild reaction conditions. Traditional hydrolase-catalysed synthesis in non-aqueous apolar media is hard due to lack of polysaccharide solubility. However, acylated starch derivatives have recently been successfully produced in other non-conventional systems: (a) surfactant-solubilised subtilisin and suspended amylose in organic media; (b) starch nanoparticles dispersed in organic medium with immobilised lipase; (c) aqueous starch gels with lipase and dispersed fatty acids. We attempt a systematic review that draws parallels between the seemingly unrelated approaches described. PMID:22138593

  18. Restriction Fragment Length Polymorphism Separates Species of the Xiphinema americanum Group.

    Science.gov (United States)

    Vrain, T C

    1993-09-01

    The Xiphinema americanum group of species is responsible for vectoring several important virus diseases to perennial crops. Variability of transmission of viruses by different species, and difficulties in separating species by morphometric measurements alone, make it essential to reassess the taxonomic position of several species in the group. The measurement of DNA sequence variability is a sensitive assay that can re-evaluate the separation of species and populations from each other. This study describes how an RFLP approach, in which the restriction sites in transcribed spacers of ribosomal repeats were detected, confirmed the separation of 16 populations of these species into X. americanum, X. rivesi, X. pacificum, and X. bricolensis.

  19. Extended Group Foliation Method and Functional Separation of Variables to Nonlinear Wave Equations

    Institute of Scientific and Technical Information of China (English)

    QU Chang-Zheng; ZHANG Shun-Li

    2005-01-01

    Generalized functional separation of variables to nonlinear evolution equations is studied in terms of the extended group foliation method, which is based on the Lie point symmetry method. The approach is applied to nonlinear wave equations with variable speed and external force. A complete classification for the wave equation which admits functional separable solutions is presented. Some known results can be recovered by this approach.

  20. Enrichment and separation of rebaudioside A from stevia glycosides by a novel adsorbent with pyridyl group

    Institute of Scientific and Technical Information of China (English)

    陈天红; 张杨; 刘晓航; 史作清; 孙君坦; 何炳林

    1999-01-01

    The adsorptive capacity and selectivity of a novel adsorbent with pyridyl group toward stevia glycosides were studied. The effect of polarity and physical structure of the sorbent on the selectivity was investigated in detail. Two separation methods were applied in the enrichment of rebaudioside A(RA). They were selective elution using methanol or ethanol solution as solvent, and dynamic chromatographic separation using pyridyl resin with high selectivity. Results show that the chromatographic separation method can effectively enrich RA from stevia glycoside with high content of stevioside.

  1. Density matrix renormalization group with efficient dynamical electron correlation through range separation

    DEFF Research Database (Denmark)

    Hedegård, Erik D.; Knecht, Stefan; Kielberg, Jesper Skau;

    2015-01-01

    We present a new hybrid multiconfigurational method based on the concept of range-separation that combines the density matrix renormalization group approach with density functional theory. This new method is designed for the simultaneous description of dynamical and static electroncorrelation...

  2. Density matrix renormalization group with efficient dynamical electron correlation through range separation

    Energy Technology Data Exchange (ETDEWEB)

    Hedegård, Erik Donovan, E-mail: erik.hedegard@phys.chem.ethz.ch; Knecht, Stefan; Reiher, Markus, E-mail: markus.reiher@phys.chem.ethz.ch [Laboratorium für Physikalische Chemie, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich (Switzerland); Kielberg, Jesper Skau; Jensen, Hans Jørgen Aagaard, E-mail: hjj@sdu.dk [Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, Odense (Denmark)

    2015-06-14

    We present a new hybrid multiconfigurational method based on the concept of range-separation that combines the density matrix renormalization group approach with density functional theory. This new method is designed for the simultaneous description of dynamical and static electron-correlation effects in multiconfigurational electronic structure problems.

  3. Group Treatment of Foster Children to Reduce Separation Conflicts Associated with Placement Breakdown.

    Science.gov (United States)

    Palmer, Sally E.

    1990-01-01

    Tested the hypothesis that placement stability for foster children would improve if they received help in resolving separation conflicts with their biological families from a group treatment program under the leadership of the child's caseworker. Important lacks in agency practice were revealed. (BB)

  4. Regioselective Acylation of Diols and Triols: The Cyanide Effect.

    Science.gov (United States)

    Peng, Peng; Linseis, Michael; Winter, Rainer F; Schmidt, Richard R

    2016-05-11

    Central topics of carbohydrate chemistry embrace structural modifications of carbohydrates and oligosaccharide synthesis. Both require regioselectively protected building blocks that are mainly available via indirect multistep procedures. Hence, direct protection methods targeting a specific hydroxy group are demanded. Dual hydrogen bonding will eventually differentiate between differently positioned hydroxy groups. As cyanide is capable of various kinds of hydrogen bonding and as it is a quite strong sterically nondemanding base, regioselective O-acylations should be possible at low temperatures even at sterically congested positions, thus permitting formation and also isolation of the kinetic product. Indeed, 1,2-cis-diols, having an equatorial and an axial hydroxy group, benzoyl cyanide or acetyl cyanide as an acylating agent, and DMAP as a catalyst yield at -78 °C the thermodynamically unfavorable axial O-acylation product; acyl migration is not observed under these conditions. This phenomenon was substantiated with 3,4-O-unproteced galacto- and fucopyranosides and 2,3-O-unprotected mannopyranosides. Even for 3,4,6-O-unprotected galactopyranosides as triols, axial 4-O-acylation is appreciably faster than O-acylation of the primary 6-hydroxy group. The importance of hydrogen bonding for this unusual regioselectivity could be confirmed by NMR studies and DFT calculations, which indicate favorable hydrogen bonding of cyanide to the most acidic axial hydroxy group supported by hydrogen bonding of the equatorial hydroxy group to the axial oxygen. Thus, the "cyanide effect" is due to dual hydrogen bonding of the axial hydroxy group which enhances the nucleophilicity of the respective oxygen atom, permitting an even faster reaction for diols than for mono-ols. In contrast, fluoride as a counterion favors dual hydrogen bonding to both hydroxy groups leading to equatorial O-acylation. PMID:27104625

  5. Group separation of coal components and new ideas of coal utilization as petroleum

    Institute of Scientific and Technical Information of China (English)

    QIN Zhi-hong; HOU Cui-li; CHEN Juan; ZHANG Li-ying; MA Jie-qiong

    2009-01-01

    Four different groups of components were separated from coal under mild conditions of extraction and stripping process. Within these groups, and with pre-separation, individual utilization of all coal components can be realized, similar to petroleum components and enhance the inherent value and utilization value of coal, as well as increase environmental benefits. The characteristics of each component were analyzed with measurements by FTIR, GC/MS, TEM and the establishment of caking properties. The results show that coal can be separated into residues, ultra-pure coal, asphaltene components and light components by adding solvents for stripping into the CS2/NMP mixed extraction solution. Those four groups of components present great differences in the presence of carbon and hydrogen elements, in the structure of functional groups, in their macroscopic structure and micro-morphology and caking properties. Every component possesses its own inherent values and approaches. A new idea of coal processes and utilization, similar to the use of petroleum is proposed.

  6. Acylated ghrelin and unacylated ghrelin inhibit INS-1 pancreas β-cell injury induced by sustained high glucose

    Institute of Scientific and Technical Information of China (English)

    王勇

    2014-01-01

    Objective To examine whether ghrelin has beneficial effect on survival of pancreatic INS-1 beta cell.Methods Rat INS-1 cells were cultured separately in 5.6mmol/L glucose(NG group),33.3 mmol/L glucose(HG group),33.3 mmol/L glucose plus 10 nmol/L acylated ghrelin(HG+AG group),and 33.3 mmol/L glucose plus 10μmol/L unacylated ghrelin(HG+UG group).After being incubated for different hours,cell survival rate was determined by MTT.Activity of caspase-3 was estimated by spectrophotometry,activity

  7. METHOD OF SEPARATING TETRAVALENT PLUTONIUM VALUES FROM CERIUM SUB-GROUP RARE EARTH VALUES

    Science.gov (United States)

    Duffield, R.B.; Stoughton, R.W.

    1959-02-01

    A method is presented for separating plutonium from the cerium sub-group of rare earths when both are present in an aqueous solution. The method consists in adding an excess of alkali metal carbonate to the solution, which causes the formation of a soluble plutonium carbonate precipitate and at the same time forms an insoluble cerium-group rare earth carbonate. The pH value must be adjusted to bctween 5.5 and 7.5, and prior to the precipitation step the plutonium must be reduced to the tetravalent state since only tetravalent plutonium will form the soluble carbonate complex.

  8. A covalent adduct of MbtN, an acyl-ACP dehydrogenase from Mycobacterium tuberculosis, reveals an unusual acyl-binding pocket.

    Science.gov (United States)

    Chai, Ai-Fen; Bulloch, Esther M M; Evans, Genevieve L; Lott, J Shaun; Baker, Edward N; Johnston, Jodie M

    2015-04-01

    Mycobacterium tuberculosis (Mtb) is the causative agent of tuberculosis. Access to iron in host macrophages depends on iron-chelating siderophores called mycobactins and is strongly correlated with Mtb virulence. Here, the crystal structure of an Mtb enzyme involved in mycobactin biosynthesis, MbtN, in complex with its FAD cofactor is presented at 2.30 Å resolution. The polypeptide fold of MbtN conforms to that of the acyl-CoA dehydrogenase (ACAD) family, consistent with its predicted role of introducing a double bond into the acyl chain of mycobactin. Structural comparisons and the presence of an acyl carrier protein, MbtL, in the same gene locus suggest that MbtN acts on an acyl-(acyl carrier protein) rather than an acyl-CoA. A notable feature of the crystal structure is the tubular density projecting from N(5) of FAD. This was interpreted as a covalently bound polyethylene glycol (PEG) fragment and resides in a hydrophobic pocket where the substrate acyl group is likely to bind. The pocket could accommodate an acyl chain of 14-21 C atoms, consistent with the expected length of the mycobactin acyl chain. Supporting this, steady-state kinetics show that MbtN has ACAD activity, preferring acyl chains of at least 16 C atoms. The acyl-binding pocket adopts a different orientation (relative to the FAD) to other structurally characterized ACADs. This difference may be correlated with the apparent ability of MbtN to catalyse the formation of an unusual cis double bond in the mycobactin acyl chain.

  9. The Brauer Group of Central Separable Monoids in a Braided Monoidal Category

    Institute of Scientific and Technical Information of China (English)

    J.M. Fernández Vilaboa; R. González Rodríguez; E. Villanueva Novoa

    2002-01-01

    For a braided monoidal category (C,(○×), K, c), in a previous paper, we construct a Brauer group B1,c(C) for the 1-Azumaya monoids in C. In this paper,we investigate separability and centrality properties for 1-Azumaya monoids when the coequalizers in C are stable. This leads to the notion of 2-Azumaya monoids,and to a new subgroup B2,c(C) of the Brauer group B1,c(C) that generalizes the analogous groups in the symmetric case. Finally, we prove that B2,c(C) and B1,c(C) are equal if the base object of the category is projective.

  10. Separations on a cellulose exchanger with salicylic acid as functional group

    International Nuclear Information System (INIS)

    The use of a cellulose compound containing salicylic acid as functional group (capacity 0.6 mequ./g) for different problems is described. The seperations Fe3+/Cu2+ and Cu2+/Ni2+ in aqueous solutions are achieved smoothly at pH 2 and 2.5 resp. In organic solvents (pyridine) copper ions are separated from copper complexes as shown by the examples Cu2+/[Cu(mnt)2]2- (mnt = maleonitril-1,2-dithiolate) and Cu2+/dibenzo[b.i.][5.9.14.18]tetraazacyclotetradecene-copper [Cu(chel)]. The complex [Cu(mnt)2]2- can be labelled with Cu-64 on a separation column, whereas [Cu-(chel)] is substition inert. (orig.)

  11. Characterization of new glycolipid biosurfactants, tri-acylated mannosylerythritol lipids, produced by Pseudozyma yeasts.

    Science.gov (United States)

    Fukuoka, Tokuma; Morita, Tomotake; Konishi, Masaaki; Imura, Tomohiro; Kitamoto, Dai

    2007-07-01

    Mannosylerythritol lipids (MELs) are glycolipid biosurfactants produced by Pseudozyma yeasts. They show not only the excellent interfacial properties but also versatile biochemical actions. In the course of MEL production from soybean oil by P. antarctica and P. rugulosa, some new extracellular glycolipids (more hydrophobic than the previously reported di-acylated MELs) were found in the culture medium. The most hydrophobic one was identified as 1-O-alka(e)noyl-4-O-[(4',6'-di-O-acetyl-2',3'-di-O-alka(e)noyl)-beta-D-mannopyranosyl]-D-erythritol, namely tri-acylated MEL. Others were tri-acylated MELs bearing only one acetyl group. The tri-acylated MEL could be prepared by the lipase-catalyzed esterification of a di-acylated MEL with oleic acid implying that the new glycolipids are synthesized from di-acylated MELs in the culture medium containing the residual fatty acids. PMID:17417694

  12. Separate groups of dopamine neurons innervate caudate head and tail encoding flexible and stable value memories

    Directory of Open Access Journals (Sweden)

    Hyoung F Kim

    2014-10-01

    Full Text Available Dopamine neurons are thought to be critical for reward value-based learning by modifying synaptic transmissions in the striatum. Yet, different regions of the striatum seem to guide different kinds of learning. Do dopamine neurons contribute to the regional differences of the striatum in learning? As a first step to answer this question, we examined whether the head and tail of the caudate nucleus of the monkey (Macaca mulatta receive inputs from the same or different dopamine neurons. We chose these caudate regions because we previously showed that caudate head neurons learn values of visual objects quickly and flexibly, whereas caudate tail neurons learn object values slowly but retain them stably. Here we confirmed the functional difference by recording single neuronal activity while the monkey performed the flexible and stable value tasks, and then injected retrograde tracers in the functional domains of caudate head and tail. The projecting dopaminergic neurons were identified using tyrosine hydroxylase immunohistochemistry. We found that two groups of dopamine neurons in the substantia nigra pars compacta project largely separately to the caudate head and tail. These groups of dopamine neurons were mostly separated topographically: head-projecting neurons were located in the rostral-ventral-medial region, while tail-projecting neurons were located in the caudal-dorsal-lateral regions of the substantia nigra. Furthermore, they showed different morphological features: tail-projecting neurons were larger and less circular than head-projecting neurons. Our data raise the possibility that different groups of dopamine neurons selectively guide learning of flexible (short-term and stable (long-term memories of object values.

  13. Regioselective self-acylating cyclodextrins in organic solvent

    Science.gov (United States)

    Cho, Eunae; Yun, Deokgyu; Jeong, Daham; Im, Jieun; Kim, Hyunki; Dindulkar, Someshwar D.; Choi, Youngjin; Jung, Seunho

    2016-03-01

    Amphiphilic cyclodextrins have been synthesized with self-acylating reaction using vinyl esters in dimethylformamide. In the present study no base, catalyst, or enzyme was used, and the structural analyses using thin layer chromatography, nuclear magnetic resonance spectroscopy and mass spectrometry show that the cyclodextrin is substituted preferentially by one acyl moiety at the C2 position of the glucose unit, suggesting that cyclodextrin functions as a regioselective catalytic carbohydrate in organic solvent. In the self-acylation, the most acidic OH group at the 2-position and the inclusion complexing ability of cyclodextrin were considered to be significant. The substrate preference was also observed in favor of the long-chain acyl group, which could be attributed to the inclusion ability of cyclodextrin cavity. Furthermore, using the model amphiphilic building block, 2-O-mono-lauryl β-cyclodextrin, the self-organized supramolecular architecture with nano-vesicular morphology in water was investigated by fluorescence spectroscopy, dynamic light scattering and transmission electron microscopy. The cavity-type nano-assembled vesicle and the novel synthetic methods for the preparation of mono-acylated cyclodextrin should be of great interest with regard to drug/gene delivery systems, functional surfactants, and carbohydrate derivatization methods.

  14. Structural properties of pepsin-solubilized collagen acylated by lauroyl chloride along with succinic anhydride

    Energy Technology Data Exchange (ETDEWEB)

    Li, Conghu [The Key Laboratory of Leather Chemistry and Engineering of Ministry of Education, Sichuan University, Chengdu 610065 (China); College of Life Sciences, Anqing Normal University, Anqing 246011 (China); Tian, Zhenhua; Liu, Wentao [The Key Laboratory of Leather Chemistry and Engineering of Ministry of Education, Sichuan University, Chengdu 610065 (China); Li, Guoying, E-mail: liguoyings@163.com [The Key Laboratory of Leather Chemistry and Engineering of Ministry of Education, Sichuan University, Chengdu 610065 (China)

    2015-10-01

    The structural properties of pepsin-solubilized calf skin collagen acylated by lauroyl chloride along with succinic anhydride were investigated in this paper. Compared with native collagen, acylated collagen retained the unique triple helix conformation, as determined by amino acid analysis, circular dichroism and X-ray diffraction. Meanwhile, the thermostability of acylated collagen using thermogravimetric measurements was enhanced as the residual weight increased by 5%. With the temperature increased from 25 to 115 °C, the secondary structure of native and acylated collagens using Fourier transform infrared spectroscopy measurements was destroyed since the intensity of the major amide bands decreased and the positions of the major amide bands shifted to lower wavenumber, respectively. Meanwhile, two-dimensional correlation spectroscopy revealed that the most sensitive bands for acylated and native collagens were amide I and II bands, respectively. Additionally, the corresponding order of the groups between native and acylated collagens was different and the correlation degree for acylated collagen was weaker than that of native collagen, suggesting that temperature played a small influence on the conformation of acylated collagen, which might be concluded that the hydrophobic interaction improved the thermostability of collagen. - Highlights: • Acylated collagen retained the unique triple helix conformation. • Acylated collagen had stronger thermostability than native collagen. • Amide I was the most sensitive band to the temperature for acylated collagen. • Amide II was the most sensitive band to the temperature for native collagen. • Auto-peak at 1680 cm{sup −1} for acylated collagen disappeared at higher temperature.

  15. Separation of compounds with multiple -OH groups from dilute aqueous solutions via complexation with organoboronate

    Energy Technology Data Exchange (ETDEWEB)

    Chow, Tina Kuo Fung

    1992-05-01

    The complexing extractant agent investigated in this work is 3-nitrophenylboronic acid (NPBA) in its anionic form (NPB). NPBA and Aliquat 336 (quaternary amine) is dissolved in 2-ethyl-l-hexanol, and the extractant is contacted with aq. NaOH. Solutes investigated were 1,2-propanediol, glycerol, fructose, sorbitol and lactic acid. Batch extraction experiments were performed at 25{degree}C. Partition coefficients, distribution ratios and loadings are reported for varying concentrations of solute and NPB. All solutes complexed with NPB{sup {minus}}, with all complexes containing only one NPB{sup {minus}} per complex. The 1:1 complexation constants for the solutes glycerol, fructose and sorbitol follow trends similar to complexation with B(OH){sub 4}{sup {minus}} (aq.), i.e. the complexation constants increase with increasing number of {minus}OH groups available for complexation. Assumption of 1:1 complex is not valid for 1, 2-propanediol, which showed overloading (more than one mole of solute complexed to one mole NPB{sup {minus}}) at higher concentrations. The {minus}OH group on the NPB{sup {minus}} which is left uncomplexed after one solute molecule had bound to the other two {minus}OH groups may be responsible for the overloading. Overloading is also observed in extraction of tactic acid, but through a different mechanism. It was found that TOMA{sup +} can extract lactic acid to an extent comparable to the uptake of lactic acid by NPB{sup {minus}}. The complexation is probably through formation of an acid-base ion pair. Losses of NPBA into the aqueous phase could lead to problems, poor economics in industrial separation processes. One way of overcoming this problem would be to incorporate the NPBA onto a solid support.

  16. Group separation and analysis of a carbon disulfide-soluble fraction from Shenfu coal by column chromatography

    Institute of Scientific and Technical Information of China (English)

    DING Ming-jie; WEI Xian-yong; ZONG Zhi-min; ZONG Ying; OUYANG Xiao-dong; HUANG Yao-guo; ZHOU Lei; ZHENG Yu-xuan; ZHOU Xiao; WEI Yan-bin

    2008-01-01

    A carbon disulfide-soluble fraction (CDSSF) from Shenfu coal was separated into five fractions by silica-gel column chromatography using hexane and n-hexane/ethyl acetate binary eluent. The five fractions include four clear group fractions and a nonpolar fraction. All the fractions were analyzed by GC/MS. A total of 204 compounds were detected from the original CDSSF and its further separated fractions, with 173 compounds more than those detected by studying the original CDSSF directly. The results demonstrate a clear group separation by column chromatography in coal organic components and a more accessibility to coal components compared with the solvent extraction only.

  17. Minor modifications to the phosphate groups and the C3' acyl chain length of lipid A in two Bordetella pertussis strains, BP338 and 18-323, independently affect Toll-like receptor 4 protein activation.

    Science.gov (United States)

    Shah, Nita R; Albitar-Nehme, Sami; Kim, Emma; Marr, Nico; Novikov, Alexey; Caroff, Martine; Fernandez, Rachel C

    2013-04-26

    Lipopolysaccharides (LPS) of Bordetella pertussis are important modulators of the immune system. Interaction of the lipid A region of LPS with the Toll-like receptor 4 (TLR4) complex causes dimerization of TLR4 and activation of downstream nuclear factor κB (NFκB), which can lead to inflammation. We have previously shown that two strains of B. pertussis, BP338 (a Tohama I-derivative) and 18-323, display two differences in lipid A structure. 1) BP338 can modify the 1- and 4'-phosphates by the addition of glucosamine (GlcN), whereas 18-323 cannot, and 2) the C3' acyl chain in BP338 is 14 carbons long, but only 10 or 12 carbons long in 18-323. In addition, BP338 lipid A can activate TLR4 to a greater extent than 18-323 lipid A. Here we set out to determine the genetic reasons for the differences in these lipid A structures and the contribution of each structural difference to the ability of lipid A to activate TLR4. We show that three genes of the lipid A GlcN modification (Lgm) locus, lgmA, lgmB, and lgmC (previously locus tags BP0399-BP0397), are required for GlcN modification and a single amino acid difference in LpxA is responsible for the difference in C3' acyl chain length. Furthermore, by introducing lipid A-modifying genes into 18-323 to generate isogenic strains with varying penta-acyl lipid A structures, we determined that both modifications increase TLR4 activation, although the GlcN modification plays a dominant role. These results shed light on how TLR4 may interact with penta-acyl lipid A species.

  18. Chemically modified polymeric resins for solid-phase extraction and group separation prior to analysis by liquid or gas chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, L.W.

    1993-07-01

    Polystyrene divinylbenzene was modified by acetyl, sulfonic acid, and quaternary ammonium groups. A resin functionalized with an acetyl group was impregnated in a PTFE membrane and used to extract and concentrate phenolic compounds from aqueous samples. The acetyl group created a surface easily wetted, making it an efficient adsorbent for polar compounds in water. The membrane stabilized the resin bed. Partially sulfonated high surface area resins are used to extract and group separate an aqueous mixture of neutral and basic organics; the bases are adsorbed electrostatically to the sulfonic acid groups, while the neutraons are adsorbed hydrophobically. A two-step elution is then used to separate the two fractions. A partially functionalized anion exchange resin is used to separate organic acids and phenols from neutrals in a similar way. Carboxylic acids are analyzed by HPLC and phenols by GC.

  19. Chlamydia trachomatis Scavenges Host Fatty Acids for Phospholipid Synthesis via an Acyl-Acyl Carrier Protein Synthetase.

    Science.gov (United States)

    Yao, Jiangwei; Dodson, V Joshua; Frank, Matthew W; Rock, Charles O

    2015-09-01

    The obligate intracellular parasite Chlamydia trachomatis has a reduced genome but relies on de novo fatty acid and phospholipid biosynthesis to produce its membrane phospholipids. Lipidomic analyses showed that 8% of the phospholipid molecular species synthesized by C. trachomatis contained oleic acid, an abundant host fatty acid that cannot be made by the bacterium. Mass tracing experiments showed that isotopically labeled palmitic, myristic, and lauric acids added to the medium were incorporated into C. trachomatis-derived phospholipid molecular species. HeLa cells did not elongate lauric acid, but infected HeLa cell cultures elongated laurate to myristate and palmitate. The elongated fatty acids were incorporated exclusively into C. trachomatis-produced phospholipid molecular species. C. trachomatis has adjacent genes encoding the separate domains of the bifunctional acyl-acyl carrier protein (ACP) synthetase/2-acylglycerolphosphoethanolamine acyltransferase gene (aas) of Escherichia coli. The CT775 gene encodes an acyltransferase (LpaT) that selectively transfers fatty acids from acyl-ACP to the 1-position of 2-acyl-glycerophospholipids. The CT776 gene encodes an acyl-ACP synthetase (AasC) with a substrate preference for palmitic compared with oleic acid in vitro. Exogenous fatty acids were elongated and incorporated into phospholipids by Escherichia coli-expressing AasC, illustrating its function as an acyl-ACP synthetase in vivo. These data point to an AasC-dependent pathway in C. trachomatis that selectively scavenges host saturated fatty acids to be used for the de novo synthesis of its membrane constituents. PMID:26195634

  20. Preparation and Characterization of Acylated Chitosan

    Institute of Scientific and Technical Information of China (English)

    LI Ming-chun; LIU Chao; XIN Mei-hua; ZHAO Huang; WANG Min; FENG Zhen; SUN Xiao-li

    2005-01-01

    Fully acylated chitosan and N, N-diacyl chitosan were prepared. The products were characterized by elemental analysis, FTIR and 1H NMR. The experimental results indicate that the average degree of acylation depends on the volume ratio of pyridine to chloroform in the reaction medium, the chain length of the acylation agent used, and the molecular weight of chitosan raw materials. The XRD measurements were carried out for pure chitosan, fully acylated chitosan and N, N-diacyl chitosan to verify the crystallinity change caused by the acylation.

  1. Antileishmanial Activity of Aldonamides and N-Acyl-Diamine Derivatives

    Directory of Open Access Journals (Sweden)

    Elaine S. Coimbra

    2008-01-01

    Full Text Available A number of lipophilic N-acyl-diamines and aldonamides have been synthesized and tested for their in vitro antiproliferative activity against Leishmania amazonensis and L. chagasi. Ribonamides, having one amino group, displayed good to moderate inhibition of parasite growth. The best result was obtained for compounds 10 and 15 with IC50 against L. chagasi below 5 μM.

  2. Efficient free fatty acid production in Escherichia coli using plant acyl-ACP thioesterases.

    Science.gov (United States)

    Zhang, Xiujun; Li, Mai; Agrawal, Arpita; San, Ka-Yiu

    2011-11-01

    Microbial biosynthesis of fatty acid-like chemicals from renewable carbon sources has attracted significant attention in recent years. Free fatty acids can be used as precursors for the production of fuels or chemicals. Free fatty acids can be produced by introducing an acyl-acyl carrier protein thioesterase gene into Escherichia coli. The presence of the acyl-ACP thioesterase will break the fatty acid elongation cycle and release free fatty acid. Depending on their sequence similarity and substrate specificity, class FatA thioesterase is active on unsaturated acyl-ACPs and class FatB prefers saturated acyl group. Different acyl-ACP thioesterases have different degrees of chain length specificity. Although some of these enzymes have been characterized from a number of sources, information on their ability to produce free fatty acid in microbial cells has not been extensively examined until recently. In this study, we examined the effect of the overexpression of acyl-ACP thioesterase genes from Diploknema butyracea, Gossypium hirsutum, Ricinus communis and Jatropha curcas on free fatty acid production. In particular, we are interested in studying the effect of different acyl-ACP thioesterase on the quantities and compositions of free fatty acid produced by an E. coli strain ML103 carrying these constructs. It is shown that the accumulation of free fatty acid depends on the acyl-ACP thioesterase used. The strain carrying the acyl-ACP thioesterase gene from D. butyracea produced approximately 0.2g/L of free fatty acid while the strains carrying the acyl-ACP thioesterase genes from R. communis and J. curcas produced the most free fatty acid at a high level of more than 2.0 g/L at 48 h. These two strains accumulated three major straight chain free fatty acids, C14, C16:1 and C16 at levels about 40%, 35% and 20%, respectively. PMID:22001432

  3. Palladium-Catalyzed Environmentally Benign Acylation.

    Science.gov (United States)

    Suchand, Basuli; Satyanarayana, Gedu

    2016-08-01

    Recent trends in research have gained an orientation toward developing efficient strategies using innocuous reagents. The earlier reported transition-metal-catalyzed carbonylations involved either toxic carbon monoxide (CO) gas as carbonylating agent or functional-group-assisted ortho sp(2) C-H activation (i.e., ortho acylation) or carbonylation by activation of the carbonyl group (i.e., via the formation of enamines). Contradicting these methods, here we describe an environmentally benign process, [Pd]-catalyzed direct carbonylation starting from simple and commercially available iodo arenes and aldehydes, for the synthesis of a wide variety of ketones. Moreover, this method comprises direct coupling of iodoarenes with aldehydes without activation of the carbonyl and also without directing group assistance. Significantly, the strategy was successfully applied to the synthesis n-butylphthalide and pitofenone. PMID:27377566

  4. Fatty acyl-CoA reductases of birds

    Directory of Open Access Journals (Sweden)

    Hellenbrand Janine

    2011-12-01

    Full Text Available Abstract Background Birds clean and lubricate their feathers with waxes that are produced in the uropygial gland, a holocrine gland located on their back above the tail. The type and the composition of the secreted wax esters are dependent on the bird species, for instance the wax ester secretion of goose contains branched-chain fatty acids and unbranched fatty alcohols, whereas that of barn owl contains fatty acids and alcohols both of which are branched. Alcohol-forming fatty acyl-CoA reductases (FAR catalyze the reduction of activated acyl groups to fatty alcohols that can be esterified with acyl-CoA thioesters forming wax esters. Results cDNA sequences encoding fatty acyl-CoA reductases were cloned from the uropygial glands of barn owl (Tyto alba, domestic chicken (Gallus gallus domesticus and domestic goose (Anser anser domesticus. Heterologous expression in Saccharomyces cerevisiae showed that they encode membrane associated enzymes which catalyze a NADPH dependent reduction of acyl-CoA thioesters to fatty alcohols. By feeding studies of transgenic yeast cultures and in vitro enzyme assays with membrane fractions of transgenic yeast cells two groups of isozymes with different properties were identified, termed FAR1 and FAR2. The FAR1 group mainly synthesized 1-hexadecanol and accepted substrates in the range between 14 and 18 carbon atoms, whereas the FAR2 group preferred stearoyl-CoA and accepted substrates between 16 and 20 carbon atoms. Expression studies with tissues of domestic chicken indicated that FAR transcripts were not restricted to the uropygial gland. Conclusion The data of our study suggest that the identified and characterized avian FAR isozymes, FAR1 and FAR2, can be involved in wax ester biosynthesis and in other pathways like ether lipid synthesis.

  5. Renormalization-group study of superfluidity and phase separation of helium mixtures immersed in a disordered porous medium

    International Nuclear Information System (INIS)

    Superfluidity and phase separation in 3He-4He mixtures immersed in aerogel are studied by renormalization-group theory. The quenched disorder imposed by aerogel, both at the atomic level and at the geometric level, is included. The calculation is conducted via the coupled renormalization-group mappings, near and away from aerogel, of the quenched probability distributions of random interactions. Random-bond effects on the onset of superfluidity and random-field effects on superfluid-superfluid phase separation are seen. The quenched randomness causes the λ line of second-order phase transitions of superfluidity onset to reach zero temperature, in agreement with general predictions and experiments. The effects of the atomic and geometric randomness of aerogel are investigated separately and jointly. copyright 1997 The American Physical Society

  6. Grafting of chitosan with fatty acyl derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Chiandotti, Roberto S.; Rodrigues, Paula C.; Akcelrud, Leni, E-mail: leni@leniak.ne [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Dept de Quimica

    2010-07-01

    The internal plasticization of chitosan with covalently linked long aliphatic branches, typically 12C, was accomplished through the condensation of the amino groups of chitosan with acidic derivatives of lauric acid, as lauroyl anhydride or lauroyl chloride, that are more reactive than the fatty acid itself. The chemical pathway led to selective N-acylation. The degree of substitution was quantitatively determined by FTIR and {sup 1}H NMR and varied between 3 and 35%. The FTIR quantitative analysis was based in a calibration method with good accuracy. The modified chitosan products were soluble in neutral water and/or DMF according to the degree of substitution. The modified chitosan films were more flexible than the pristine, non-modified ones. (author)

  7. An Evaluation of School-Based Support Groups for Children of Divorced or Separated Parents. No. 195.

    Science.gov (United States)

    Rosenstein-Manner, Merle

    In the 1989-90 school year, POINT (Parents and Organizations in North Toronto) and Social Work Services, Toronto (Ontario) Board of Education, conducted six peer-support groups for those elementary school children (grades 5-8) in North Toronto whose parents were divorced or separated. Topics covered in 10 weekly 1-hour sessions included parental…

  8. Validation of limited sampling models (LSM) for estimating AUC in therapeutic drug monitoring - is a separate validation group required?

    NARCIS (Netherlands)

    Proost, J. H.

    2007-01-01

    Objective: Limited sampling models (LSM) for estimating AUC in therapeutic drug monitoring are usually validated in a separate group of patients, according to published guidelines. The aim of this study is to evaluate the validation of LSM by comparing independent validation with cross-validation us

  9. Versatility of acyl-acyl carrier protein synthetases.

    Science.gov (United States)

    Beld, Joris; Finzel, Kara; Burkart, Michael D

    2014-10-23

    The acyl carrier protein (ACP) requires posttranslational modification with a 4'-phosphopantetheine arm for activity, and this thiol-terminated modification carries cargo between enzymes in ACP-dependent metabolic pathways. We show that acyl-ACP synthetases (AasSs) from different organisms are able to load even, odd, and unnatural fatty acids onto E. coli ACP in vitro. Vibrio harveyi AasS not only shows promiscuity for the acid substrate, but also is active upon various alternate carrier proteins. AasS activity also extends to functional activation in living organisms. We show that exogenously supplied carboxylic acids are loaded onto ACP and extended by the E. coli fatty acid synthase, including unnatural fatty acid analogs. These analogs are further integrated into cellular lipids. In vitro characterization of four different adenylate-forming enzymes allowed us to disambiguate CoA-ligases and AasSs, and further in vivo studies show the potential for functional application in other organisms. PMID:25308274

  10. Renormalization-Group Theory Study of Superfluidity and Phase Separation of Helium Mixtures Immersed in Jungle-Gym Aerogel

    Science.gov (United States)

    Lopatnikova, Anna; Berker, A. Nihat

    1997-03-01

    Superfluidity and phase separation in ^3He-^4He mixtures immersed in jungle-gym (non-random) aerogel are studied by renormalization-group theory.(Phys. Rev. B, in press (1996)) Phase diagrams are calculated for a variety of aerogel concentrations. Superfluidity at very low ^4He concentrations and a depressed tricritical temperature are found at the onset of superfluidity. A superfluid-superfluid phase separation, terminating at an isolated critical point, is found entirely within the superfluid phase. These phenomena, and trends with respect to aerogel concentration, are explained by the connectivity and tenuousness of jungle-gym aerogel.

  11. Degrees of Separation--Balancing Intervention and Independence in Group Work Assignments

    Science.gov (United States)

    Burdett, Jane

    2007-01-01

    Group work is a widely used learning approach in higher education where it is seen as encouraging the development of collaborative skills and attitudes while producing an assessable product. Group assignments can, however, create dilemmas and tensions for both staff and students. Students often seek academic intervention in the form of support and…

  12. Acylated flavone glycosides from Veronica

    DEFF Research Database (Denmark)

    Albach, Dirk C.; Grayer, Renée J.; Jensen, Søren Rosendal;

    2003-01-01

    A survey of the flavonoid glycosides of selected taxa in the genus Veronica yielded two new acylated 5,6,7,3',4'-pentahydroxyflavone (6-hydroxyluteolin) glycosides and two rare allose-containing acylated 5,7,8,4'-tetrahydroxyflavone (isoscutellarein) glycosides. The new compounds were isolated from...... Veronica (melittoside and globularifolin) were also isolated from V. intercedens....

  13. Acyl-CoA metabolism and partitioning

    DEFF Research Database (Denmark)

    Grevengoed, Trisha J; Klett, Eric L; Coleman, Rosalind A

    2014-01-01

    Long-chain fatty acyl-coenzyme As (CoAs) are critical regulatory molecules and metabolic intermediates. The initial step in their synthesis is the activation of fatty acids by one of 13 long-chain acyl-CoA synthetase isoforms. These isoforms are regulated independently and have different tissue e...

  14. Report of the Energy Research Advisory Board study group on advanced isotope separation

    International Nuclear Information System (INIS)

    The Panel reviewed Advanced Isotope Separation (AIS) technology and Advanced Gas Centrifuge (AGC) programs in the context of potential needs and costs for uranium enrichment. The benefit of a successful AIS or AGC program would be a substantial reduction in enrichment costs below those of current centrifuge plants or below the power cost alone for gaseous diffusion plants. This report attempts to provide firm guidance for the next 2 to 3 years, at which time a further evaluation should guide decisions in regard to enrichment supply and development choices. On the basis of our perception of the long-term economic benefits of a successful AIS development, we support the continued pursuit of this option. In the interim, major requirements for enrichment must be satisfied. We assume that DOE will develop a firm funding plan for gaseous diffusion operations and power contracting to assure that the necessary supply of power will be available to meet the separative work commitments of the US enrichment enterprise. We recommend that the AIS program office further identify the key technical uncertainties of the various programs, thereby establishing the basis for near-term R and D leading to a decision whether and when to proceed with full-scale development. We believe that a stronger atomic vapor laser isotope separation (AVLIS) program would result from a consolidation of the Lawrence Livermore National Laboratory (LLNL) and Jersey Nuclear Avco Isotopes (JNAI) teams, leading to a more competitive AVLIS process. Hence, we recommend that DOE attempt to negotiate with JNAI to form a single, integrated, government-funded AVLIS program with appropriate elements of LLNL, JNAI and UCC-ND. We further recommend that JNAI be designated as lead laboratory in this program. We recommend that the DOE: continue with the first 2.2 million SWU increment of the gas centrifuge program, and continue the Advanced Gas Centrifuge development program, with high priority

  15. Reaching the boundary between stellar kinematic groups and very wide binaries. The Washington Double Stars with the widest angular separations

    CERN Document Server

    Caballero, Jose A

    2009-01-01

    Aims. I look for and characterise very wide binaries and multiple systems with projected physical separations larger than s = 0.1 pc, which is generally believed to be a sharp upper limit to the distribution of wide binay semimajor axes. Methods. I investigated in detail 30 Washington Double Stars with angular separations rho > 1000 arcsec. I discarded 23 of them as probably unbound systems based on discordant astrometry, photometry, spectral types, and radial velocities. The remaining seven systems were subject to a comprehensive data compilation and derivation (multi-wavelength photometry, heliocentric distance, multiplicity, age, mass, metallicity, membership in young kinematic group). Results. Of the seven very wide systems, six have projected physical separations larger than the hypothetical cutoff at s = 0.1 pc; four of them have separations s > 0.2 pc. Although there are two systems in young kinematic groups (namely HD 136654 and BD+32 2572 in the Hyades Supercluster, and AU Mic and AT Mic AB in the be...

  16. A Simple, Rapid and Mild One Pot Synthesis of Benzene Ring Acylated and Demethylated Analogues of Harmine under Solvent-free Conditions

    OpenAIRE

    Siddiqui, Bina S.; Syed Imran Hassan; Farhat Farhat; Syed Nawazish Ali; Sabira Begum

    2008-01-01

    A simple, rapid, solvent-free, room temperature one pot synthesis of benzene ring acylated and demethylated analogues of harmine using acyl halides/acid anhydrides and AlCl3 has been developed. Eight different acyl halides/acid anhydrides were used in the synthesis. The resulting mixture of products was separated by column chromatography to afford 10- and 12-monoacyl analogues, along with 10,12-diacyl-11-hydroxy products. In five cases the corresponding 10-acyl-11-hydroxy analogues were also ...

  17. A Simple, Rapid and Mild One Pot Synthesis of Benzene Ring Acylated and Demethylated Analogues of Harmine under Solvent-free Conditions

    Directory of Open Access Journals (Sweden)

    Bina S. Siddiqui

    2008-08-01

    Full Text Available A simple, rapid, solvent-free, room temperature one pot synthesis of benzene ring acylated and demethylated analogues of harmine using acyl halides/acid anhydrides and AlCl3 has been developed. Eight different acyl halides/acid anhydrides were used in the synthesis. The resulting mixture of products was separated by column chromatography to afford 10- and 12-monoacyl analogues, along with 10,12-diacyl-11-hydroxy products. In five cases the corresponding 10-acyl-11-hydroxy analogues were also obtained. Yields from the eight syntheses (29 products in total were in the 6-34% range and all compounds were fully characterized.

  18. Variables separated equations: Strikingly different roles for the Branch Cycle Lemma and the Finite Simple Group Classification

    CERN Document Server

    Fried, Michael d

    2010-01-01

    H. Davenport's Problem asks: What can we expect of two polynomials, over the integers, with the same ranges on almost all residue class fields? This stood out among many separated variable problems posed by Davenport, D.J. Lewis and A. Schinzel. By bounding the degrees, but expanding the maps and variables in Davenport's Problem, Galois stratification enhanced the separated variable theme, solving an Ax and Kochen problem from their Artin Conjecture work. J. Denef and F. Loeser applied this to add Chow motive coefficients to previously introduced zeta functions on a diophantine statement. By restricting the variables, but leaving the degrees unbounded, we found the striking distinction between Davenport's problem over the rationals, solved by applying the Branch Cycle Lemma, and its generalization over any number field, solved using the simple group classification. This encouraged J. Thompson to formulate the genus 0 problem on rational function monodromy groups. R. Guralnick and Thompson led its solution in ...

  19. The effective comparison between emotion-focused cognitive behavioral group therapy and cognitive behavioral group therapy in children with separation anxiety disorder

    Directory of Open Access Journals (Sweden)

    Afrooz Afshari

    2014-01-01

    Full Text Available Background: Emotion-focused cognitive behavioral therapy (ECBT is a new form of CBT with emotion regulation components. This form of treatment is suggested to be employed to improve dysregulation of anxiety and other kind of emotions in anxious children. This study observed and compared the effectiveness of CBT and ECBT on anxiety symptoms; sadness and anger management; and cognitive emotion regulation strategies in children with separation anxiety disorder (SAD. Materials and Methods: This study is a randomized clinical trial. Subjects were 30 children from 9 to 13-years-old (15 girls and 15 boys with diagnosis of SAD, being randomly assigned to CBT, ECBT, and control groups (five girls and five boys in each group. Subject children in CBT group participated in 10-h weekly sessions within Coping Cat manual; whereas, subject children in ECBT group contributed in 12-h weekly sessions within ECBT. The control group received no treatment. The Screen for Child Anxiety Related Emotional Disorders (SCARED; child and parent forms, Children′s Emotion Management Scale (CEMS; anger and sadness forms, and Cognitive Emotion Regulation Questionnaire (CERQ tests administered to all subjects in pretest, posttest, and the follow-up measurement (3 months later. Analysis of covariance (ANCOVA repeated measure and Kruskal-Wallis were applied to analyze data by Statistical Package for Social Sciences (SPSS software package (v. 20. Results: CBT and ECBT; demonstrated no significant difference in reducing separation anxiety and total anxiety symptoms from parent and children′s reports. ECBT effectively increased anger coping and decreased negative cognitive strategies and dysregulation of anger in children, both in posttest and follow-up. Also, ECBT reduced sadness dysregulation and increased sadness coping, though these significant advantages were lost in 3 months later follow-up. CBT reduced negative cognitive strategies in follow-up and increased sadness coping

  20. Xeroderma pigmentosum group A protein loads as a separate factor onto DNA lesions

    NARCIS (Netherlands)

    S. Rademakers (Suzanne); M. Volker (Marcel); D. Hoogstraten (Deborah); A.L. Nigg (Alex); M.J. Mone; A.A. van Zeeland; A.B. Houtsmuller (Adriaan); W. Vermeulen (Wim); J.H.J. Hoeijmakers (Jan)

    2003-01-01

    textabstractNucleotide excision repair (NER) is the main DNA repair pathway in mammals for removal of UV-induced lesions. NER involves the concerted action of more than 25 polypeptides in a coordinated fashion. The xeroderma pigmentosum group A protein (XPA) has been suggested to function as a centr

  1. Structural relationship of the lipid A acyl groups to activation of murine Toll-like receptor 4 by lipopolysaccharides from pathogenic strains of Burkholderia mallei, Acinetobacter baumannii and Pseudomonas aeruginosa

    Directory of Open Access Journals (Sweden)

    Kirill V Korneev

    2015-11-01

    Full Text Available Toll-like receptor 4 (TLR4 is required for activation of innate immunity upon recognition of lipopolysaccharide (LPS of Gram-negative bacteria. The ability of TLR4 to respond to a particular LPS species is important since insufficient activation may not prevent bacterial growth while excessive immune reaction may lead to immunopathology associated with sepsis. Here we investigated the biological activity of LPS from Burkholderia mallei that causes glanders, and from the two well-known opportunistic pathogens Acinetobacter baumannii and Pseudomonas aeruginosa (causative agents of nosocomial infections. For each bacterial strain, R-form LPS preparations were purified by hydrophobic chromatography and the chemical structure of lipid A, an LPS structural component, was elucidated by HR-MALDI-TOF mass spectrometry. The biological activity of LPS samples was evaluated by their ability to induce production of proinflammatory cytokines, such as IL-6 and TNF, by bone marrow-derived macrophages (BMDM. Our results demonstrate direct correlation between the biological activity of LPS from these pathogenic bacteria and the extent of their lipid A acylation.

  2. Structural Relationship of the Lipid A Acyl Groups to Activation of Murine Toll-Like Receptor 4 by Lipopolysaccharides from Pathogenic Strains of Burkholderia mallei, Acinetobacter baumannii, and Pseudomonas aeruginosa

    Science.gov (United States)

    Korneev, Kirill V.; Arbatsky, Nikolay P.; Molinaro, Antonio; Palmigiano, Angelo; Shaikhutdinova, Rima Z.; Shneider, Mikhail M.; Pier, Gerald B.; Kondakova, Anna N.; Sviriaeva, Ekaterina N.; Sturiale, Luisa; Garozzo, Domenico; Kruglov, Andrey A.; Nedospasov, Sergei A.; Drutskaya, Marina S.; Knirel, Yuriy A.; Kuprash, Dmitry V.

    2015-01-01

    Toll-like receptor 4 (TLR4) is required for activation of innate immunity upon recognition of lipopolysaccharide (LPS) of Gram-negative bacteria. The ability of TLR4 to respond to a particular LPS species is important since insufficient activation may not prevent bacterial growth while excessive immune reaction may lead to immunopathology associated with sepsis. Here, we investigated the biological activity of LPS from Burkholderia mallei that causes glanders, and from the two well-known opportunistic pathogens Acinetobacter baumannii and Pseudomonas aeruginosa (causative agents of nosocomial infections). For each bacterial strain, R-form LPS preparations were purified by hydrophobic chromatography and the chemical structure of lipid A, an LPS structural component, was elucidated by HR-MALDI-TOF mass spectrometry. The biological activity of LPS samples was evaluated by their ability to induce production of proinflammatory cytokines, such as IL-6 and TNF, by bone marrow-derived macrophages. Our results demonstrate direct correlation between the biological activity of LPS from these pathogenic bacteria and the extent of their lipid A acylation. PMID:26635809

  3. Xeroderma pigmentosum group A protein loads as a separate factor onto DNA lesions

    OpenAIRE

    Rademakers, Suzanne; Volker, Marcel; Hoogstraten, Deborah; Nigg, Alex; Mone, M.J.; van Zeeland, A A; Houtsmuller, Adriaan; Vermeulen, Wim; Hoeijmakers, Jan

    2003-01-01

    textabstractNucleotide excision repair (NER) is the main DNA repair pathway in mammals for removal of UV-induced lesions. NER involves the concerted action of more than 25 polypeptides in a coordinated fashion. The xeroderma pigmentosum group A protein (XPA) has been suggested to function as a central organizer and damage verifier in NER. How XPA reaches DNA lesions and how the protein is distributed in time and space in living cells are unknown. Here we studied XPA in vivo by using a cell li...

  4. Fatty acyl-CoA reductase

    Energy Technology Data Exchange (ETDEWEB)

    Reiser, Steven E.; Somerville, Chris R.

    1998-12-01

    The present invention relates to bacterial enzymes, in particular to an acyl-CoA reductase and a gene encoding an acyl-CoA reductase, the amino acid and nucleic acid sequences corresponding to the reductase polypeptide and gene, respectively, and to methods of obtaining such enzymes, amino acid sequences and nucleic acid sequences. The invention also relates to the use of such sequences to provide transgenic host cells capable of producing fatty alcohols and fatty aldehydes.

  5. Catalytic Acylation of Anisole over Some Zeolites

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    4-Methoxyacetophenone(4-MAP) was synthesized by the acylation of anisole with acetic anhydride in the presence of HY zeolite.The addition of an appropriate amount of some solvent such as dichloromethane,chloroform,carbon disulfide or chlorobenzene to the reaction system can improve the yield of the acylated product to a certain extent.HY zeolite used can be recovered,and reused after being regenerated,obtaining almost the same yield of 4-MAP as the fresh zeolite.

  6. Novel endogenous N-acyl amides activate TRPV1-4 receptors, BV-2 microglia, and are regulated in brain in an acute model of inflammation

    Directory of Open Access Journals (Sweden)

    Siham eRaboune

    2014-08-01

    Full Text Available A family of endogenous lipids, structurally analogous to the endogenous cannabinoid, N-arachidonoyl ethanolamine (Anandamide, and called N-acyl amides have emerged as a family of biologically active compounds at TRP receptors. N-acyl amides are constructed from an acyl group and an amine via an amide bond. This same structure can be modified by changing either the fatty acid or the amide to form potentially hundreds of lipids. More than 70 N-acyl amides have been identified in nature. We have ongoing studies aimed at isolating and characterizing additional members of the family of N-acyl amides in both central and peripheral tissues in mammalian systems. Here, using a unique in-house library of over 70 N-acyl amides we tested the following three hypotheses: 1 Additional N-acyl amides will have activity at TRPV1-4, 2 Acute peripheral injury will drive changes in CNS levels of N-acyl amides, and 3 N-acyl amides will regulate calcium in CNS-derived microglia. Through these studies, we have identified 20 novel N-acyl amides that collectively activate (stimulating or inhibiting TRPV1-4. Using lipid extraction and HPLC coupled to tandem mass spectrometry we showed that levels of at least 10 of these N-acyl amides that activate TRPVs are regulated in brain after intraplantar carrageenan injection. We then screened the BV2 microglial cell line for activity with this N-acyl amide library and found overlap with TRPV receptor activity as well as additional activators of calcium mobilization from these lipids. Together these data provide new insight into the family of N-acyl amides and their roles as signaling molecules at ion channels, in microglia, and in the brain in the context of inflammation.

  7. Synthesis and biological activities of turkesterone 11?-acyl derivatives

    Directory of Open Access Journals (Sweden)

    Laurence Dinan

    2003-02-01

    Full Text Available Turkesterone is a phytoecdysteroid possessing an 11alpha-hydroxyl group. It is an analogue of the insect steroid hormone 20-hydroxyecdysone. Previous ecdysteroid QSAR and molecular modelling studies predicted that the cavity of the ligand-binding domain of the ecdysteroid receptor would possess space in the vicinity of C-11/C-12 of the ecdysteroid. We report the regioselective synthesis of a series of turkesterone 11alpha-acyl derivatives in order to explore this possibility. The structures of the analogues have been unambiguously determined by spectroscopic means (NMR and low-resolution mass spectrometry. Purity was verified by HPLC. Biological activities have been determined in Drosophila melanogaster BII cell-based bioassay for ecdysteroid agonists and in an in vitro radioligand-displacement assay using bacterially expressed D. melanogaster EcR/USP receptor proteins. The 11alpha-acyl derivatives do retain a significant amount of biological activity relative to the parent ecdysteroid. Further, although activity initially drops with the extension of the acyl chain length (C2 to C4, it then increases (C6 to C10, before decreasing again (C14 and C20. The implications of these findings for the interaction of ecdysteroids with the ecdysteroid receptor and potential applications in the generation of affinity-labelled and fluorescently-tagged ecdysteroids are discussed.

  8. Muoniated acyl and thioacyl radicals

    Energy Technology Data Exchange (ETDEWEB)

    McKenzie, Iain [TRIUMF and Department of Chemistry, 8888 University Drive, Simon Fraser University, Burnaby B.C., V5A 1S6 (Canada); Brodovitch, Jean-Claude [TRIUMF and Department of Chemistry, 8888 University Drive, Simon Fraser University, Burnaby B.C., V5A 1S6 (Canada); Ghandi, Khashayar [TRIUMF and Department of Chemistry, 8888 University Drive, Simon Fraser University, Burnaby B.C., V5A 1S6 (Canada); Percival, Paul W. [TRIUMF and Department of Chemistry, 8888 University Drive, Simon Fraser University, Burnaby B.C., V5A 1S6 (Canada)]. E-mail: percival@sfu.ca

    2006-03-31

    The product of the reaction of muonium with tert-butylisocyanate was previously assigned as the muoniated tert-butylaminyl radical (I. McKenzie, J.-C. Brodovitch, K. Ghandi, S. Kecman, P. W. Percival, Physica B 326 (2003) 76). This assignment is incorrect since the muon and {sup 14}N hyperfine-coupling constants (hfcc) of this radical would have the opposite sign, which is in conflict with the experimental results. The radical is now reassigned as the muoniated N-tert-butylcarbamoyl radical, based on the similarities between the experimental muon and {sup 14}N hfcc and hfcc calculated at the UB3LYP/6-311G(d,p)//UB3LYP/EPR-III level. The large zero-point energy in the N-Mu bond results in the dissociation barrier of the muoniated N-tert-butylcarbamoyl radical being above the combined energy of the reactants, in contrast to the N-tert-butylcarbamoyl radical where the dissociation barrier lies below the combined energy of the reactants. The reaction of muonium with tert-butylisothiocyanate produced both conformers of the muoniated N-tert-butylthiocarbamoyl radical and their assignment was based on the similarities between the experimental and calculated muon hfcc. These are the first acyl and thioacyl radicals to be directly detected by muon spin spectroscopy.

  9. Nieuwe N-acyl-anthranilzuurverbindingen en toepassing van N-anthranilzuur-verbindingen bij de bestrijding van insecten.

    NARCIS (Netherlands)

    Blaakmeer, A.; Beek, van T.A.; Groot, de Ae.; Loon, van J.J.A.; Schoonhoven, L.M.

    1992-01-01

    The invention relates to the use of an N-acyl-anthranilic acid compound of the formula 1, where: R1 to R9 inclusive represent a hydrogen atom, halogen atom, alkyl group, phenyl group, hydroxyl group, alkoxy group, acyloxy group or a sugar radical, with the option of two adjacent groups out of R1 to

  10. Proteomic Analysis of a Poplar Cell Suspension Culture Suggests a Major Role of Protein S-Acylation in Diverse Cellular Processes.

    Science.gov (United States)

    Srivastava, Vaibhav; Weber, Joseph R; Malm, Erik; Fouke, Bruce W; Bulone, Vincent

    2016-01-01

    S-acylation is a reversible post-translational modification of proteins known to be involved in membrane targeting, subcellular trafficking, and the determination of a great variety of functional properties of proteins. The aim of this work was to identify S-acylated proteins in poplar. The use of an acyl-biotin exchange method and mass spectrometry allowed the identification of around 450 S-acylated proteins, which were subdivided into three major groups of proteins involved in transport, signal transduction, and response to stress, respectively. The largest group of S-acylated proteins was the protein kinase superfamily. Soluble N-ethylmaleimide-sensitive factor-activating protein receptors, band 7 family proteins and tetraspanins, all primarily related to intracellular trafficking, were also identified. In addition, cell wall related proteins, including cellulose synthases and other glucan synthases, were found to be S-acylated. Twenty four of the identified S-acylated proteins were also enriched in detergent-resistant membrane microdomains, suggesting S-acylation plays a key role in the localization of proteins to specialized plasma membrane subdomains. This dataset promises to enhance our current understanding of the various functions of S-acylated proteins in plants. PMID:27148305

  11. Natural variability in acyl moieties of sugar esters produced by certain tobacco and other Solanaceae species.

    Science.gov (United States)

    Kroumova, Antoaneta B M; Zaitlin, Dave; Wagner, George J

    2016-10-01

    A unique feature of glandular trichomes of plants in the botanical family Solanaceae is that they produce sugar esters (SE), chemicals that have been shown to possess insecticidal, antifungal, and antibacterial properties. Sugar esters of tobacco (Nicotiana tabacum) provide pest resistance, and are important flavor precursors in oriental tobacco cultivars. Acyl moieties of SEs in Nicotiana spp., petunia, and tomato are shown to vary with respect to carbon length and isomer structure (2-12 carbon chain length; anteiso-, iso-, and straight-chain). Sugar esters and their acyl groups could serve as a model to explore the basis of phenotypic diversity and adaptation to natural and agricultural environments. However, information on the diversity of acyl composition among species, cultivars, and accessions is lacking. Herein, described is the analysis of SE acyl groups found in 21 accessions of Nicotiana obtusifolia (desert tobacco), six of Nicotiana occidentalis subsp. hesperis, three of Nicotiana alata, two of N. occidentalis, four modern tobacco cultivars, five petunia hybrids, and one accession each of a primitive potato (Solanum berthaultii) and tomato (Solanum pennellii). A total of 20 different acyl groups was observed that were represented differently among cultivars, species, and accessions. In Nicotiana species, acetate and iso- and anteiso-branched acids prevailed. Straight-chain groups (2-8 carbons) were prominent in petunias, while octanoic acid was prominent in N. alata and N. × sanderae. Two unexpected acyl groups, 8-methyl nonanoate and decanoate were found in N. occidentalis subsp. hesperis. Longer chain groups were found in the petunia, tomato, and potato species studied. PMID:27262877

  12. II-VI oxides phase separate whereas the corresponding carbonates order: The stabilizing role of anionic groups

    Science.gov (United States)

    Chan, J. A.; Zunger, Alex

    2009-10-01

    The formation enthalpies of isovalent, isostructural rocksalt alloys, (A,B) , where X=O such as (Ca,Mg)O, are typically unfavorable (positive) for both ordered and random phases. Simple replacement of the single-atom anion, X , by a larger anionic group, such as CO3 or SO4 , is able to induce a favorable (negative) formation enthalpy, leading to the formation of the ordered alternate monolayer, (CaCO3)1/(MgCO3)1 , dolomite structure. The underlying cause of this behavior is analyzed by breaking down the formation process in a Born-Haber-like cycle into volume and cell-shape deformation, chemical exchange, and cell-internal relaxation using first-principles density-functional theory calculations in the generalized gradient approximation. It is found that when the anion is a group (CO3) , rather than a single atom (O), the energy gained from the internal relaxation overcomes the energy required to compensate the volume mismatch. This explains the general experimental trends of phase separation in isovalent, isostructural alloys without internal-anion structure, compared to ordering tendencies when the anionic group removes internal strain. The importance of obtaining structural ideality in the design of stable solid solutions is highlighted.

  13. Action of N-acylated ambroxol derivatives on secretion of chloride ions in human airway epithelia.

    Science.gov (United States)

    Yamada, Takahiro; Takemura, Yoshizumi; Niisato, Naomi; Mitsuyama, Etsuko; Iwasaki, Yoshinobu; Marunaka, Yoshinori

    2009-03-13

    We report the effects of new N-acylated ambroxol derivatives (TEI-588a, TEI-588b, TEI-589a, TEI-589b, TEI-602a and TEI-602b: a, aromatic amine-acylated derivative; b, aliphatic amine-acylated derivative) induced from ambroxol (a mucolytic agent to treat human lung diseases) on Cl(-) secretion in human submucosal serous Calu-3 cells under a Na(+)/K(+)/2Cl(-) cotransporter-1 (NKCC1)-mediated hyper-secreting condition. TEI-589a, TEI-589b and TEI-602a diminished hyper-secretion of Cl(-) by diminishing the activity of NKCC1 without blockade of apical Cl(-) channel (TEI-589a>TEI-602a>TEI-589b), while any other tested compounds including ambroxol had no effects on Cl(-) secretion. These indicate that the inhibitory action of an aromatic amine-acylated derivative on Cl(-) secretion is stronger that that of an aliphatic amine-acylated derivative, and that 3-(2,5-dimethyl)furoyl group has a strong action in inhibition of Cl(-) secretion than cyclopropanoyl group. We here indicate that TEI-589a, TEI-589b and TEI-602a reduce hyper-secretion to an appropriate level in the airway, providing a possibility that the compound can be an effective drug in airway obstructive diseases including COPD by reducing the airway resistance under a hyper-secreting condition.

  14. Catalytic Acylation of Ethylidenecyclohexane over Zeolite Catalysts

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Some environmentally friendly catalysts such as HY and H-β zeolites,various cation-exchanged β zeolites,and some other solids have been used in the acylation reaction of ethylidenecyclohexane with acetic anhydride at room temperature to synthesize 3-(1-cyclohexenyl)-2-butanone instead of conventional catalysts.The effect of the amount of HY zeolite used on the acylation reaction was investigated.The yield of the acylated product was 72% in the case of n(ethylidenecyclohexane)∶n(acetic anhydride)∶m(HY zeolite)=1 mmol∶10 mmol∶0.100 g,reaction temperature:25 ℃,and reaction time:2 h.The regenerated HY zeolite showed almost the same catalytic activity as the fresh zeolite.

  15. Putative neuroprotective actions of N-acyl-ethanolamines

    DEFF Research Database (Denmark)

    Hansen, Harald S.; Moesgaard, B.; Petersen, G.;

    2002-01-01

    particular attention since it is a partial agonist for the cannabinoid receptors, for which 2-arachidonoylglycerol is the full agonist. In addition, anandamide may also activate the vanilloid receptor. Anandamide usually amounts to 1-10% of NAEs, as the vast majority of N-acyl groups are saturated...... when other phospholipids are subjected to rapid degradation. This is an important biosynthetic aspect of NAPE and NAE, as NAEs may be neuroprotective by a number of different mechanisms involving both receptor activation and non-receptor-mediated effects, e.g. by binding to cannabinoid receptors...

  16. Minimizing acylation of peptides in PLGA microspheres

    OpenAIRE

    Zhang, Ying; Schwendeman, Steven P.

    2012-01-01

    The main objective of this study was to characterize and find mechanisms to prevent acylation of therapeutic peptides encapsulated in glucose-star poly(D,L-lactic-co-glycolic acid) (PLGA) microspheres. The effect of addition of divalent cation salts CaCl2, MnCl2 as well as carboxymethyl chitosan (CMCS) on inhibition of acylation of octreotide (Oct), salmon calcitonin (sCT), and human parathyroid hormone (hPTH) was evaluated. Peptide content and integrity inside the degrading microspheres was ...

  17. Separation of compounds with multiple -OH groups from dilute aqueous solutions via complexation with organoboronate. [1,2-propanediol

    Energy Technology Data Exchange (ETDEWEB)

    Chow, Tina Kuo Fung.

    1992-05-01

    The complexing extractant agent investigated in this work is 3-nitrophenylboronic acid (NPBA) in its anionic form (NPB). NPBA and Aliquat 336 (quaternary amine) is dissolved in 2-ethyl-l-hexanol, and the extractant is contacted with aq. NaOH. Solutes investigated were 1,2-propanediol, glycerol, fructose, sorbitol and lactic acid. Batch extraction experiments were performed at 25{degree}C. Partition coefficients, distribution ratios and loadings are reported for varying concentrations of solute and NPB. All solutes complexed with NPB{sup {minus}}, with all complexes containing only one NPB{sup {minus}} per complex. The 1:1 complexation constants for the solutes glycerol, fructose and sorbitol follow trends similar to complexation with B(OH){sub 4}{sup {minus}} (aq.), i.e. the complexation constants increase with increasing number of {minus}OH groups available for complexation. Assumption of 1:1 complex is not valid for 1, 2-propanediol, which showed overloading (more than one mole of solute complexed to one mole NPB{sup {minus}}) at higher concentrations. The {minus}OH group on the NPB{sup {minus}} which is left uncomplexed after one solute molecule had bound to the other two {minus}OH groups may be responsible for the overloading. Overloading is also observed in extraction of tactic acid, but through a different mechanism. It was found that TOMA{sup +} can extract lactic acid to an extent comparable to the uptake of lactic acid by NPB{sup {minus}}. The complexation is probably through formation of an acid-base ion pair. Losses of NPBA into the aqueous phase could lead to problems, poor economics in industrial separation processes. One way of overcoming this problem would be to incorporate the NPBA onto a solid support.

  18. Generation of fatty acids by an acyl esterase in the bioluminescent system of Photobacterium phosphoreum

    International Nuclear Information System (INIS)

    The fatty acid reductase complex from Photobacterium phosphoreum has been discovered to have a long chain ester hydrolase activity associated with the 34K protein component of the complex. This protein has been resolved from the other components (50K and 58K) of the fatty acid reductase complex with a purity of > 95% and found to catalyze the transfer of acyl groups from acyl-CoA primarily to thiol acceptors with a low level of transfer to glycerol and water. Addition of the 50K protein of the complex caused a dramatic change in specificity increasing the transfer to oxygen acceptors. The acyl-CoA hydrolase activity increased almost 10-fold, and hence free fatty acids can be generated by the 34K protein when it is present in the fatty acid reductase complex. Hydrolysis of acyl-S-mercaptoethanol and acyl-1-glycerol and the ATP-dependent reduction of the released fatty acids to aldehyde for the luminescent reaction were also demonstrated for the reconstituted fatty acid reductase complex, raising the possibility that the immediate source of fatty acids for this reaction in vivo could be the membrane lipids and/or the fatty acid synthetase system

  19. Synthesis of N-Acylated Amino Acid Surfactant from L-Proline and Palmitoyl Chloride

    International Nuclear Information System (INIS)

    A biodegradable, less toxic and environmentally friendly N-acylated amino acid surfactant was prepared from the amino acid L-proline and palmitoyl chloride through acylation reaction using the Schotten-Baumann reaction condition. The reaction result was a white flake form and the percentage of the crude yield was 72 % with melting point in range of 52 - 58 degree Celsius. Functional group of amide which was detected using Fourier Transform Infrared method showed the presence of N-palmitoyl proline. The purity analysis using High Performance Liquid Chromatography and Thin Layer Chromatography showed the result was a mixture compound. (author)

  20. S-Acylation of the cellulose synthase complex is essential for its plasma membrane localization.

    Science.gov (United States)

    Kumar, Manoj; Wightman, Raymond; Atanassov, Ivan; Gupta, Anjali; Hurst, Charlotte H; Hemsley, Piers A; Turner, Simon

    2016-07-01

    Plant cellulose microfibrils are synthesized by a process that propels the cellulose synthase complex (CSC) through the plane of the plasma membrane. How interactions between membranes and the CSC are regulated is currently unknown. Here, we demonstrate that all catalytic subunits of the CSC, known as cellulose synthase A (CESA) proteins, are S-acylated. Analysis of Arabidopsis CESA7 reveals four cysteines in variable region 2 (VR2) and two cysteines at the carboxy terminus (CT) as S-acylation sites. Mutating both the VR2 and CT cysteines permits CSC assembly and trafficking to the Golgi but prevents localization to the plasma membrane. Estimates suggest that a single CSC contains more than 100 S-acyl groups, which greatly increase the hydrophobic nature of the CSC and likely influence its immediate membrane environment. PMID:27387950

  1. Synthesis, Surface Active Properties and Cytotoxicity of Sodium N-Acyl Prolines.

    Science.gov (United States)

    Sreenu, Madhumanchi; Narayana Prasad, Rachapudi Badari; Sujitha, Pombala; Kumar, Chityal Ganesh

    2015-01-01

    Sodium N-acyl prolines (NaNAPro) were synthesized using mixture of fatty acids obtained from coconut, palm, karanja, Sterculia foetida and high oleic sunflower oils via Schotten-Baumann reaction in 58-75% yields to study the synergetic effect of mixture of hydrophobic fatty acyl functionalities like saturation, unsaturation and cyclopropene fatty acids with different chain lengths and aliphatic hetero cyclic proline head group on their surface and cytotoxicity activities. The products were characterized by chromatographic and spectral techniques. The synthesized products were evaluated for their surface active properties such as surface tension, wetting power, foaming characteristics, emulsion stability, calcium tolerance, critical micelle concentration (CMC) and thermodynamic properties. The results revealed that all the products exhibited superior surface active properties like CMC, calcium tolerance and emulsion stability as compared to the standard surfactant, sodium lauryl sulphate (SLS). In addition, palm, Sterculia foetida and high oleic sunflower fatty N-acyl prolines exhibited promising cytotoxicity against different tumor cell lines.

  2. Role of acylCoA binding protein in acylCoA transport, metabolism and cell signaling

    DEFF Research Database (Denmark)

    Knudsen, J; Jensen, M V; Hansen, J K;

    1999-01-01

    Long chain acylCoA esters (LCAs) act both as substrates and intermediates in intermediary metabolism and as regulators in various intracellular functions. AcylCoA binding protein (ACBP) binds LCAs with high affinity and is believed to play an important role in intracellular acylCoA transport...

  3. P53 Mutations Change Phosphatidylinositol Acyl Chain Composition

    Directory of Open Access Journals (Sweden)

    Adam Naguib

    2015-01-01

    Full Text Available Phosphatidylinositol phosphate (PIP second messengers relay extracellular growth cues through the phosphorylation status of the inositol sugar, a signal transduction system that is deregulated in cancer. In stark contrast to PIP inositol head-group phosphorylation, changes in phosphatidylinositol (PI lipid acyl chains in cancer have remained ill-defined. Here, we apply a mass-spectrometry-based method capable of unbiased high-throughput identification and quantification of cellular PI acyl chain composition. Using this approach, we find that PI lipid chains represent a cell-specific fingerprint and are unperturbed by serum-mediated signaling in contrast to the inositol head group. We find that mutation of Trp53 results in PIs containing reduced-length fatty acid moieties. Our results suggest that the anchoring tails of lipid second messengers form an additional layer of PIP signaling in cancer that operates independently of PTEN/PI3-kinase activity but is instead linked to p53.

  4. Tailoring the separation behavior of hybrid organosilica membranes by adjusting the structure of the organic bridging group

    NARCIS (Netherlands)

    H.L. Castricum; G.G. Paradis; M.C. Mittelmeijer-Hazeleger; R. Kreiter; J.F. Vente; J.E. ten Elshof

    2011-01-01

    Hybrid organically linked silica is a highly promising class of materials for the application in energy-efficient molecular separation membranes. Its high stability allows operation under aggressive working conditions. Herein is reported the tailoring of the separation performance of these hybrid si

  5. Hyphenation of supercritical fluid chromatography and two-dimensional gas chromatography-mass spectrometry for group type separations.

    Science.gov (United States)

    Potgieter, H; van der Westhuizen, R; Rohwer, E; Malan, D

    2013-06-14

    The Fischer-Tropsch (FT) process produces a variety of compounds over a wide carbon number range and the synthetic crude oil produced by this process is rich in highly valuable olefins and oxygenates, which crude oil only contains at trace levels. The characterization of these products is very challenging even when using comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GC×GC-TOF-MS). The separation between cyclic paraffins and olefins is especially difficult since they elute in similar positions on the GC×GC chromatogram and since they have identical molecular masses with indistinguishable fragmentation patterns. Previously, a high performance liquid chromatography (HPLC) fractionation procedure was used prior to GC×GC-TOF-MS analysis to distinguish between alkenes and alkanes, both cyclic and non-cyclic, however, there was co-elution of the solvents used in the HPLC fractionation procedure, and the volatile components in the gasoline sample and the dilution introduced by the off-line fractionation procedure made it very difficult to investigate components present at very low concentrations. The hyphenation of supercritical fluid chromatography (SFC) to GC×GC is less complicated and the removal of the supercritical CO2 can be easily achieved without any loss of the volatile sample components, eliminating the introduction of co-eluting solvents as well as the dilution effect. This paper describes the on-line hyphenation of SFC to a GC×GC system in order to comprehensively characterize the chemical groups (saturates, unsaturates, oxygenates and aromatics) in an FT sample. PMID:23647609

  6. Enzymatic Acylation of Anthocyanin Isolated from Black Rice with Methyl Aromatic Acid Ester as Donor: Stability of the Acylated Derivatives.

    Science.gov (United States)

    Yan, Zheng; Li, Chunyang; Zhang, Lixia; Liu, Qin; Ou, Shiyi; Zeng, Xiaoxiong

    2016-02-10

    The enzymatic acylation of anthocyanin from black rice with aromatic acid methyl esters as acyl donors and Candida antarctica lipase B was carried out under reduced pressure. The highest conversion of 91% was obtained with benzoic acid methyl ester as acyl donor; cyanidin 3-(6″-benzoyl)-glucoside, cyanidin 3-(6″-salicyloyl)-glucoside, and cyanidin 3-(6″-cinnamoyl)-glucoside were successfully synthesized. This is the first report on the enzymatic acylation of anthocyanin from black rice with methyl aromatic esters as acyl donors and lipase as biocatalyst. Furthermore, the acylation with aromatic carboxylic acids enhanced both the thermostability and light resistivity of anthocyanin. In particular, cyanidin 3-(6″-cinnamoyl)-glucoside was the most stable among the three acylated anthocyanins synthesized. PMID:26766135

  7. Problems concerning the accumulation of separated plutonium. Report of an advisory group meeting held in Vienna, 26-29 April 1993

    International Nuclear Information System (INIS)

    Due to the delays worldwide in the development and starting up of fast breeder reactors (which require large amounts of plutonium at startup) and the ongoing reprocessing of spent fuel (which produces separated plutonium), significant quantities of separated plutonium are being created. An Advisory Group meeting was held in April 1993 to consider this situation. The meeting had two primary objectives: to determine the magnitude of the plutonium accumulations and to identify potential problems related to this accumulation of separated plutonium. In this document IAEA estimates of present and projected inventories of separated plutonium are presented and discussed. Document also contains presentations from representatives of Member States on national programmes for production and utilization of separated plutonium. Refs, figs and tabs

  8. Serum acylated ghrelin concentrations in response to short-term overfeeding in normal weight, overweight, and obese men.

    Directory of Open Access Journals (Sweden)

    Danny Wadden

    Full Text Available BACKGROUND: Ghrelin, an orexigenic gut hormone secreted primarily from the stomach, is involved in energy homeostasis. However, little data is available regarding its response to energy surplus and the development of human obesity. OBJECTIVE: The present study investigated the response of circulating acylated ghrelin to a 7-day positive energy challenge. DESIGN: A total of 68 healthy young men were overfed 70% more calories than required, for 1-week. Subjects were classified based on percent body fat (measured by dual-energy X-ray absorptiometry as normal weight, overweight, and obese. Serum acylated ghrelin concentration was measured before and after the positive energy challenge. Additionally, the relationship between acylated ghrelin and obesity-related phenotypes including weight, body mass index, percent body fat, cholesterol, HDL-c, LDL-c, glucose, insulin and homeostasis model assessment of insulin resistance and β-cell function at baseline and change due to overfeeding, were assessed. RESULTS: Contrary to our expectations, serum acylated ghrelin was significantly increased in response to overfeeding and the increase was independent of obesity status. There was no significant difference in fasting acylated ghrelin between normal weight, overweight, and obese men at baseline. Acylated ghrelin was negatively correlated with weight and BMI for normal weight and with BMI in overweight men. Also ghrelin was correlated with change in weight and BMI in overweight (negative relationship and obese (positive relationship groups. CONCLUSION: Our results showed that circulating acylated ghrelin was increased after a 7-day positive energy challenge regardless of adiposity status. However, acylated ghrelin was correlated with change in weight and BMI in opposing directions, in overweight and obese subjects respectively, thus dependent on obesity status.

  9. Applying Acylated Fucose Analogues to Metabolic Glycoengineering

    OpenAIRE

    Julia Rosenlöcher; Verena Böhrsch; Michael Sacharjat; Véronique Blanchard; Christoph Giese; Volker Sandig; Christian P R Hackenberger; Stephan Hinderlich

    2015-01-01

    Manipulations of cell surface glycosylation or glycan decoration of selected proteins hold immense potential for exploring structure-activity relations or increasing glycoprotein quality. Metabolic glycoengineering describes the strategy where exogenously supplied sugar analogues intercept biosynthetic pathways and are incorporated into glycoconjugates. Low membrane permeability, which so far limited the large-scale adaption of this technology, can be addressed by the introduction of acylated...

  10. Concentrations of long-chain acyl-acyl carrier proteins during fatty acid synthesis by chloroplasts isolated from pea (Pisum sativum), safflower (Carthamus tinctoris), and amaranthus (Amaranthus lividus) leaves

    International Nuclear Information System (INIS)

    Fatty acid synthesis from [1-14C]acetate by chloroplasts isolated from peas and amaranthus was linear for at least 15 min, whereas incorporation of the tracer into long-chain acyl-acyl carrier protein (ACP) did not increase after 2-3 min. When reactions were transferred to the dark after 3-5 min, long-chain acyl-ACPs lost about 90% of their radioactivity and total fatty acids retained all of theirs. Half-lives of the long-chain acyl-ACPs were estimated to be 10-15 s. Concentrations of palmitoyl-, stearoyl-, and oleoyl-ACP as indicated by equilibrium labeling during steady-state fatty acid synthesis, ranged from 0.6-1.1, 0.2-0.7, and 0.4-1.6 microM, respectively, for peas and from 1.6-1.9, 1.3-2.6, and 0.6-1.4 microM, respectively, for amaranthus. These values are based on a chloroplast volume of 47 microliters/mg chlorophyll and varied according to the mode of the incubation. A slow increase in activity of the fatty acid synthetase in safflower chloroplasts resulted in long-chain acyl-ACPs continuing to incorporate labeled acetate for 10 min. Upon re-illumination following a dark break, however, both fatty acid synthetase activity and acyl-ACP concentrations increased very rapidly. Palmitoyl-ACP was present at concentrations up to 2.5 microM in safflower chloroplasts, whereas those of stearoyl- and oleoyl-ACPs were in the lower ranges measured for peas. Acyl-ACPs were routinely separated from extracts of chloroplasts that had been synthesising long-chain fatty acids from labeled acetate by a minor modification of the method of Mancha et al. The results compared favorably with those obtained using alternative analytical methods such as adsorption to filter paper and partition chromatography on silicic acid columns

  11. The effective comparison between emotion-focused cognitive behavioral group therapy and cognitive behavioral group therapy in children with separation anxiety disorder

    OpenAIRE

    Afshari, Afrooz; Neshat-Doost, Hamid Taher; Maracy, Mohammad Reza; Ahmady, Mozhgan Kar; Amiri, Shole

    2014-01-01

    Background: Emotion-focused cognitive behavioral therapy (ECBT) is a new form of CBT with emotion regulation components. This form of treatment is suggested to be employed to improve dysregulation of anxiety and other kind of emotions in anxious children. This study observed and compared the effectiveness of CBT and ECBT on anxiety symptoms; sadness and anger management; and cognitive emotion regulation strategies in children with separation anxiety disorder (SAD). Materials and Methods: This...

  12. N-acylation of ethanolamine using lipase: a chemoselective catalyst

    OpenAIRE

    Mazaahir Kidwai; Roona Poddar; Poonam Mothsra

    2009-01-01

    The N-acylation of ethanolamine (2) with various fatty acids 1a–d and esters of fatty acids 1e–h using Candida antarctica B lipase (Novozym® 435) are described and optimum conditions for selective N-acylation rather than O-acylation are also discussed. Microwave assisted solution phase, solid supported and conventional methods were investigated and results were compared. There is a synergy between the enzyme catalysis and microwave irradiation.

  13. N-acylation of ethanolamine using lipase: a chemoselective catalyst

    Directory of Open Access Journals (Sweden)

    Mazaahir Kidwai

    2009-03-01

    Full Text Available The N-acylation of ethanolamine (2 with various fatty acids 1a–d and esters of fatty acids 1e–h using Candida antarctica B lipase (Novozym® 435 are described and optimum conditions for selective N-acylation rather than O-acylation are also discussed. Microwave assisted solution phase, solid supported and conventional methods were investigated and results were compared. There is a synergy between the enzyme catalysis and microwave irradiation.

  14. Identification of Variables Associated with Group Separation in Descriptive Discriminant Analysis: Comparison of Methods for Interpreting Structure Coefficients

    Science.gov (United States)

    Finch, Holmes

    2010-01-01

    Discriminant Analysis (DA) is a tool commonly used for differentiating among 2 or more groups based on 2 or more predictor variables. DA works by finding 1 or more linear combinations of the predictors that yield maximal difference among the groups. One common goal of researchers using DA is to characterize the nature of group difference by…

  15. Combination of electromembrane extraction and liquid-phase microextraction in a single step: Simultaneous group separation of acidic and basic drugs

    DEFF Research Database (Denmark)

    Huang, Chuixiu; Seip, Knut Fredrik; Gjelstad, Astrid;

    2015-01-01

    in the range of 76%-86%. Longer extraction time provided higher recoveries for the acidic drugs, but this somewhat deteriorated the group separation. Matrices effects from the coexisting acidic drugs/basic drugs were tested, and we observed that simultaneous EME/LPME was not affected by coexisting drugs...

  16. Plasma levels of acylated ghrelin in patients with functional dyspepsia

    Institute of Scientific and Technical Information of China (English)

    Yeon Soo Kim; Joon Seong Lee; Tae Hee Lee; Joo Young Cho; Jin Oh Kim; Wan Jung Kim; Hyun Gun Kim; Seong Ran Jeon; Hoe Su Jeong

    2012-01-01

    AIM:To investigate the relationship between plasma acylated ghrelin levels and the pathophysiology of functional dyspepsia.METHODS:Twenty-two female patients with functional dyspepsia and twelve healthy volunteers were recruited for the study.The functional dyspepsia patients were each diagnosed based on the Rome Ⅲ criteria.Eligible patients completed a questionnaire concerning the severity of 10 symptoms.Plasma acylated ghrelin levels before and after a meal were determined in the study participants using a commercial human acylated enzyme immunoassay kit; electrogastrograms were performed for 50 min before and after a standardized 10-min meal containing 265 kcal.RESULTS:There were no significant differences in plasma acylated ghrelin levels between healthy volunteers and patients with functional dyspepsia.However,in patients with functional dyspepsia,there was a negative correlation between fasting plasma acylated ghrelin levels and the sum score of epigastric pain (r =-0.427,P =0.047) and a positive correlation between the postprandial/fasting plasma acylated ghrelin ratio and the sum score of early satiety (r =0.428,P =0.047).Additionally,there was a negative correlation between fasting acylated ghrelin plasma levels and fasting normogastria (%) (r =-0.522,P =0.013).Interestingly,two functional dyspepsia patients showed paradoxically elevated plasma acylated ghrelin levels after the meal.CONCLUSION:Abnormal plasma acylated ghrelin levels before or after a meal may be related to several of the dyspeptic symptoms seen in patients with functional dyspepsia.

  17. Acyl-acyl carrier protein as a source of fatty acids for bacterial bioluminescence

    International Nuclear Information System (INIS)

    Pulse-chase experiments with [3H]tetradecanoic acid and ATP showed that the bioluminescence-related 32-kDa acyltransferase from Vibrio harveyi can specifically catalyze the deacylation of a 3H-labeled 18-kDa protein observed in extracts of this bacterium. The 18-kDa protein has been partially purified and its physical and chemical properties strongly indicate that it is fatty acyl-acyl carrier protein (acyl-ACP). Both this V. harveyi [3H]acylprotein and [3H]palmitoyl-ACP from Escherichia coli were substrates in vitro for either the V. harveyi 32-kDa acyltransferase or the analogous enzyme (34K) from Photobacterium phosphoreum. TLC analysis indicated that the hexane-soluble product of the reaction is fatty acid. No significant cleavage of either E. coli or V. harveyi tetradecanoyl-ACP was observed in extracts of these bacteria unless the 32-kDa or 34K acyltransferase was present. Since these enzymes are believed to be responsible for the supply of fatty acids for reduction to form the aldehyde substrate of luciferase, the above results suggest that long-chain acyl-ACP is the source of fatty acids for bioluminescence

  18. Veronica: Acylated flavone glycosides as chemosystematic markers

    DEFF Research Database (Denmark)

    Albach, Dirk C.; Grayer, Renée J.; Kite, Geoffrey C.;

    2005-01-01

    HPLC/DAD and LCeMS of an extract of Veronica spicata subgenus Pseudolysimachium, Plantaginaceae) revealed the presence of six 6-hydroxyluteolin glycosides acylated with phenolic acids, three of which are new compounds and which we called spicosides. A flavonoid survey of seven more species...... instead. Spicosides appeared to be common in subgenus Pseudolysimachium (detected in five out of eight species), but we did not find them in subgenus Pentasepalae. Previously, acetylated 8-hydroxyflavone glycosides have been isolated from or detected in eight species of V. subgenus Pentasepalae (in 13...

  19. Novel Structural Components Contribute to the High Thermal Stability of Acyl Carrier Protein from Enterococcus faecalis.

    Science.gov (United States)

    Park, Young-Guen; Jung, Min-Cheol; Song, Heesang; Jeong, Ki-Woong; Bang, Eunjung; Hwang, Geum-Sook; Kim, Yangmee

    2016-01-22

    Enterococcus faecalis is a Gram-positive, commensal bacterium that lives in the gastrointestinal tracts of humans and other mammals. It causes severe infections because of high antibiotic resistance. E. faecalis can endure extremes of temperature and pH. Acyl carrier protein (ACP) is a key element in the biosynthesis of fatty acids responsible for acyl group shuttling and delivery. In this study, to understand the origin of high thermal stabilities of E. faecalis ACP (Ef-ACP), its solution structure was investigated for the first time. CD experiments showed that the melting temperature of Ef-ACP is 78.8 °C, which is much higher than that of Escherichia coli ACP (67.2 °C). The overall structure of Ef-ACP shows the common ACP folding pattern consisting of four α-helices (helix I (residues 3-17), helix II (residues 39-53), helix III (residues 60-64), and helix IV (residues 68-78)) connected by three loops. Unique Ef-ACP structural features include a hydrophobic interaction between Phe(45) in helix II and Phe(18) in the α1α2 loop and a hydrogen bonding between Ser(15) in helix I and Ile(20) in the α1α2 loop, resulting in its high thermal stability. Phe(45)-mediated hydrophobic packing may block acyl chain binding subpocket II entry. Furthermore, Ser(58) in the α2α3 loop in Ef-ACP, which usually constitutes a proline in other ACPs, exhibited slow conformational exchanges, resulting in the movement of the helix III outside the structure to accommodate a longer acyl chain in the acyl binding cavity. These results might provide insights into the development of antibiotics against pathogenic drug-resistant E. faecalis strains.

  20. Serum Levels of Acyl-Carnitines along the Continuum from Normal to Alzheimer's Dementia.

    Directory of Open Access Journals (Sweden)

    Adriana Cristofano

    Full Text Available This study aimed to determine the serum levels of free L-carnitine, acetyl-L-carnitine and 34 acyl-L-carnitine in healthy subjects and in patients with or at risk of Alzheimer's disease. Twenty-nine patients with probable Alzheimer's disease, 18 with mild cognitive impairment of the amnestic type, 24 with subjective memory complaint and 46 healthy subjects were enrolled in the study, and the levels of carnitine and acyl-carnitines were measured by tandem mass spectrometry. The concentrations of acetyl-L-carnitine progressively decreased passing from healthy subjects group (mean±SD, 5.6±1.3 μmol/L to subjective memory complaint (4.3±0.9 μmol/L, mild cognitive impairment (4.0±0.53 μmol/L, up to Alzheimer's disease (3.5±0.6 μmol/L group (p<0.001. The differences were significant for the comparisons: healthy subjects vs. subjective memory complaint, mild cognitive impairment or Alzheimer's disease group; and subjective memory complaint vs. Alzheimer's disease group. Other acyl-carnitines, such as malonyl-, 3-hydroxyisovaleryl-, hexenoyl-, decanoyl-, dodecanoyl-, dodecenoyl-, myristoyl-, tetradecenoyl-, hexadecenoyl-, stearoyl-, oleyl- and linoleyl-L-carnitine, showed a similar decreasing trend, passing from healthy subjects to patients at risk of or with Alzheimer's disease. These results suggest that serum acetyl-L-carnitine and other acyl-L-carnitine levels decrease along the continuum from healthy subjects to subjective memory complaint and mild cognitive impairment subjects, up to patients with Alzheimer's disease, and that the metabolism of some acyl-carnitines is finely connected among them. These findings also suggest that the serum levels of acetyl-L-carnitine and other acyl-L-carnitines could help to identify the patients before the phenotype conversion to Alzheimer's disease and the patients who would benefit from the treatment with acetyl-L-carnitine. However, further validation on a larger number of samples in a longitudinal

  1. Serum Levels of Acyl-Carnitines along the Continuum from Normal to Alzheimer's Dementia

    Science.gov (United States)

    Sapere, Nadia; La Marca, Giancarlo; Angiolillo, Antonella; Vitale, Michela; Corbi, Graziamaria; Scapagnini, Giovanni; Intrieri, Mariano; Russo, Claudio

    2016-01-01

    This study aimed to determine the serum levels of free L-carnitine, acetyl-L-carnitine and 34 acyl-L-carnitine in healthy subjects and in patients with or at risk of Alzheimer’s disease. Twenty-nine patients with probable Alzheimer’s disease, 18 with mild cognitive impairment of the amnestic type, 24 with subjective memory complaint and 46 healthy subjects were enrolled in the study, and the levels of carnitine and acyl-carnitines were measured by tandem mass spectrometry. The concentrations of acetyl-L-carnitine progressively decreased passing from healthy subjects group (mean±SD, 5.6±1.3 μmol/L) to subjective memory complaint (4.3±0.9 μmol/L), mild cognitive impairment (4.0±0.53 μmol/L), up to Alzheimer’s disease (3.5±0.6 μmol/L) group (p<0.001). The differences were significant for the comparisons: healthy subjects vs. subjective memory complaint, mild cognitive impairment or Alzheimer’s disease group; and subjective memory complaint vs. Alzheimer’s disease group. Other acyl-carnitines, such as malonyl-, 3-hydroxyisovaleryl-, hexenoyl-, decanoyl-, dodecanoyl-, dodecenoyl-, myristoyl-, tetradecenoyl-, hexadecenoyl-, stearoyl-, oleyl- and linoleyl-L-carnitine, showed a similar decreasing trend, passing from healthy subjects to patients at risk of or with Alzheimer’s disease. These results suggest that serum acetyl-L-carnitine and other acyl-L-carnitine levels decrease along the continuum from healthy subjects to subjective memory complaint and mild cognitive impairment subjects, up to patients with Alzheimer’s disease, and that the metabolism of some acyl-carnitines is finely connected among them. These findings also suggest that the serum levels of acetyl-L-carnitine and other acyl-L-carnitines could help to identify the patients before the phenotype conversion to Alzheimer’s disease and the patients who would benefit from the treatment with acetyl-L-carnitine. However, further validation on a larger number of samples in a longitudinal

  2. Group vs. single mindfulness meditation: exploring avoidance, impulsivity, and weight management in two separate mindfulness meditation settings.

    Science.gov (United States)

    Mantzios, Michail; Giannou, Kyriaki

    2014-07-01

    Recent research has identified that mindfulness meditation in group settings supports people who are trying to lose weight. The present research investigated mindfulness meditation in group and individual settings, and explored the potential impact on weight loss and other factors (i.e. mindfulness, impulsivity, and avoidance) that may assist or hinder weight loss. Specifically, the hypotheses tested were that the group setting assisted dieters more than the individual setting by reducing weight, cognitive-behavioral avoidance, and impulsivity and by increasing mindfulness. Participants (n = 170) who were trying to lose weight were randomly assigned to practice meditation for 6 weeks within a group or independently. Measurements in mindfulness, cognitive-behavioral avoidance, impulsivity, and weight occurred twice (pre- and post-intervention). Results indicated that participants in the group setting lost weight and lowered their levels of cognitive-behavioral avoidance, while impulsivity and mindfulness remained stable. On the other hand, participants in the individual condition lost less weight, while there was an increase in cognitive-behavioral avoidance and mindfulness scores, but a decrease in impulsivity. Seeing that benefits and limitations observed in group settings are not replicated when people meditate alone, this study concluded that mindfulness meditation in individual settings needs to be used with caution, although there are some potential benefits that could aid future weight loss research. PMID:24585500

  3. Understanding Acyl Chain and Glycerolipid Metabolism in Plants

    Energy Technology Data Exchange (ETDEWEB)

    Ohlrogge, John B.

    2013-11-05

    Progress is reported in these areas: acyl-editing in initial eukaryotic lipid assembly in soybean seeds; identification and characterization of two Arabidopsis thaliana lysophosphatidyl acyltransferases with preference for lysophosphatidylethanolamine; and characterization and subcellular distribution of lysolipid acyl transferase activity of pea leaves.

  4. Enzymatic synthesis and NMR studies of acylated sucrose acetates

    NARCIS (Netherlands)

    Steverink-De Zoete, M.C.; Kneepkens, M.F.M.; Waard, de P.; Woudenberg-van Oosterom, M.; Gotlieb, K.F.; Slaghek, T.

    1999-01-01

    The lipase-catalyzed esterification of partially acetylated sucrose has been studied. It was shown that the chemical acetylation increased the reaction rate of the subsequent enzymatic acylation. Thus it was possible to perform the enzymatic acylation in the absence of solvents while underivatized s

  5. Oxidative activation of dihydropyridine amides to reactive acyl donors

    DEFF Research Database (Denmark)

    Funder, Erik Daa; Trads, Julie Brender; Gothelf, Kurt Vesterager

    2015-01-01

    Amides of 1,4-dihydropyridine (DHP) are activated by oxidation for acyl transfer to amines, alcohols and thiols. In the reduced form the DHP amide is stable towards reaction with amines at room temperature. However, upon oxidation with DDQ the acyl donor is activated via a proposed pyridinium...

  6. Improvement of separation efficiencies of anion-exchange chromatography using monolithic silica capillary columns modified with polyacrylates and polymethacrylates containing tertiary amino or quaternary ammonium groups.

    Science.gov (United States)

    Watanabe, Yuta; Ikegami, Tohru; Horie, Kanta; Hara, Takeshi; Jaafar, Jafariah; Tanaka, Nobuo

    2009-10-30

    Anion-exchange (AEX) columns were prepared by on-column polymerization of acrylates and methacrylates containing tertiary amino or quaternary ammonium groups on monolithic silica in a fused silica capillary modified with anchor groups. The columns provided a plate height (H) of less than 10 microm at optimum linear velocity (u) with keeping their high permeability (K=9-12 x 10(-14) m2). Among seven kinds of AEX columns, a monolithic silica column modified with poly(2-hydroxy-3-(4-methylpiperazin-1-yl)propyl methacrylates) (HMPMA) showed larger retentions and better selectivities for nucleotides and inorganic anions than the others. The HMPMA column of 410 mm length produced 42,000-55,000 theoretical plates (N) at a linear velocity of 0.97 mm/s with a backpressure of 3.8 MPa. The same column could be employed for a fast separation of inorganic anions in 1.8 min at a linear velocity of 5.3 mm/s with a backpressure of 20 MPa. In terms of van Deemter plot and separation impedance, the HMPMA column showed higher performance than a conventional particle-packed AEX column. The HMPMA column showed good recovery of a protein, trypsin inhibitor, and it was applied to the separation of proteins and tryptic digest of bovine serum albumin (BSA) in a gradient elution, to provide better separation compared to a conventional particle-packed AEX column. PMID:19683243

  7. Dynamics of the separation of amino acid and mineral salt in the stationary dialysis of solutions with an MK-40 profiled sulfo group cation exchange membrane

    Science.gov (United States)

    Vasil'eva, V. I.; Vorob'eva, E. A.

    2012-11-01

    The conjugated diffusion transport of amino acid and mineral salt through a profiled sulfo group cation exchange membrane that simulates the extraction of amino acid from wash waters of microbiological production containing mineral components not used in synthesis is studied. The competitive nature of the conjugation of flows resulting in a decrease in the rate of the mass transfer of components and their separation factor is established from a comparative analysis of experimental data on the diffusion transfer of phenylalanine and sodium chloride in the form of hydrogen from individual and mixed solutions through a profiled sulfo group cation exchange membrane. The range of concentrations and the ratio of components in solution corresponding to the effective separation of phenylalanine and sodium chloride are determined.

  8. ACCEPTABILITY EVALUATION FOR USING ICRP TISSUE WEIGHTING FACTORS TO CALCULATE EFFECTIVE DOSE VALUE FOR SEPARATE GENDER-AGE GROUPS OF RUSSIAN FEDERATION

    Directory of Open Access Journals (Sweden)

    L. V. Repin

    2013-01-01

    Full Text Available An article describes radiation risk factors for several gender-age population groups according to Russian statistical and medical-demographic data, evaluates the lethality rate for separate nosologic forms of malignant neoplasms based on Russian cancer registries according to the method of the International Agency for Cancer Research. Relative damage factors are calculated for the gender-age groups under consideration. The tissue weighting factors recommended by ICRP to calculate effective doses are compared with relative damage factors calculated by ICRP for the nominal population and with similar factors calculated in this work for separate population cohorts in theRussian Federation. The significance of differences and the feasibility of using tissue weighting factors adapted for the Russian population in assessing population risks in cohorts of different gender-age compositions have been assessed.

  9. Erbium trifluoromethanesulfonate-catalyzed Friedel–Crafts acylation using aromatic carboxylic acids as acylating agents under monomode-microwave irradiation

    DEFF Research Database (Denmark)

    Tran, Phuong Hoang; Hansen, Poul Erik; Nguyen, Hai Truong;

    2015-01-01

    Erbium trifluoromethanesulfonate is found to be a good catalyst for the Friedel–Crafts acylation of arenes containing electron-donating substituents using aromatic carboxylic acids as the acylating agents under microwave irradiation. An effective, rapid and waste-free method allows the preparation...... of a wide range of aryl ketones in good yields and in short reaction times with minimum amounts of waste...

  10. Fast Color Grouping and Slow Color Inhibition: Evidence for Distinct Temporal Windows for Separate Processes in Preview Search

    Science.gov (United States)

    Braithwaite, Jason J.; Humphreys, Glyn W.; Hulleman, Johan; Watson, Derrick G.

    2007-01-01

    The authors report 4 experiments that examined color grouping and negative carryover effects in preview search via a probe detection task (J. J. Braithwaite, G. W. Humphreys, & J. Hodsoll, 2003). In Experiment 1, there was evidence of a negative color carryover from the preview to new items, using both search and probe detection measures. There…

  11. Friedel-Craft Acylation of ar-Himachalene: Synthesis of Acyl-ar-Himachalene and a New Acyl-Hydroperoxide

    Directory of Open Access Journals (Sweden)

    Abdallah Karim

    2011-07-01

    Full Text Available Friedel-Craft acylation at 100 °C of 2,5,9,9-tetramethyl-6,7,8,9-tetrahydro-5H-benzocycloheptene [ar-himachalene (1], a sesquiterpenic hydrocarbon obtained by catalytic dehydrogenation of α-, β- and γ-himachalenes, produces a mixture of two compounds: (3,5,5,9-tetramethyl-6,7,8,9-tetrahydro-5H-benzocyclohepten-2-yl-ethanone (2, in 69% yield, with a conserved reactant backbone, and 3, with a different skeleton, in 21% yield. The crystal structure of 3 reveals it to be 1-(8-ethyl-8-hydroperoxy-3,5,5-trimethyl-5,6,7,8-tetrahydronaphthalen-2-yl-ethanone. In this compound O-H…O bonds form dimers. These hydrogen-bonds, in conjunction with weaker C-H…O interactions, form a more extended supramolecular arrangement in the crystal.

  12. Preparation of a technology development roadmap for the Accelerator Transmutation of Waste (ATW) System : report of the ATW separations technologies and waste forms technical working group

    International Nuclear Information System (INIS)

    In response to a Congressional mandate to prepare a roadmap for the development of Accelerator Transmutation of Waste (ATW) technology, a Technical Working Group comprised of members from various DOE laboratories was convened in March 1999 for the purpose of preparing that part of the technology development roadmap dealing with the separation of certain radionuclides for transmutation and the disposal of residual radioactive wastes from these partitioning operations. The Technical Working Group for ATW Separations Technologies and Waste Forms completed its work in June 1999, having carefully considered the technology options available. A baseline process flowsheet and backup process were identified for initial emphasis in a future research, development and demonstration program. The baseline process combines aqueous and pyrochemical processes to permit the efficient separation of the uranium, technetium, iodine and transuranic elements from the light water reactor (LWR) fuel in the head-end step. The backup process is an all- pyrochemical system. In conjunction with the aqueous process, the baseline flowsheet includes a pyrochemical process to prepare the transuranic material for fabrication of the ATW fuel assemblies. For the internal ATW fuel cycle the baseline process specifies another pyrochemical process to extract the transuranic elements, Tc and 1 from the ATW fuel. Fission products not separated for transmutation and trace amounts of actinide elements would be directed to two high-level waste forms, one a zirconium-based alloy and the other a glass/sodalite composite. Baseline cost and schedule estimates are provided for a RD and D program that would provide a full-scale demonstration of the complete separations and waste production flowsheet within 20 years

  13. Preparation of a technology development roadmap for the Accelerator Transmutation of Waste (ATW) System : report of the ATW separations technologies and waste forms technical working group.

    Energy Technology Data Exchange (ETDEWEB)

    Collins, E.; Duguid, J.; Henry, R.; Karell, E.; Laidler, J.; McDeavitt, S.; Thompson, M.; Toth, M.; Williamson, M.; Willit, J.

    1999-08-12

    In response to a Congressional mandate to prepare a roadmap for the development of Accelerator Transmutation of Waste (ATW) technology, a Technical Working Group comprised of members from various DOE laboratories was convened in March 1999 for the purpose of preparing that part of the technology development roadmap dealing with the separation of certain radionuclides for transmutation and the disposal of residual radioactive wastes from these partitioning operations. The Technical Working Group for ATW Separations Technologies and Waste Forms completed its work in June 1999, having carefully considered the technology options available. A baseline process flowsheet and backup process were identified for initial emphasis in a future research, development and demonstration program. The baseline process combines aqueous and pyrochemical processes to permit the efficient separation of the uranium, technetium, iodine and transuranic elements from the light water reactor (LWR) fuel in the head-end step. The backup process is an all- pyrochemical system. In conjunction with the aqueous process, the baseline flowsheet includes a pyrochemical process to prepare the transuranic material for fabrication of the ATW fuel assemblies. For the internal ATW fuel cycle the baseline process specifies another pyrochemical process to extract the transuranic elements, Tc and 1 from the ATW fuel. Fission products not separated for transmutation and trace amounts of actinide elements would be directed to two high-level waste forms, one a zirconium-based alloy and the other a glass/sodalite composite. Baseline cost and schedule estimates are provided for a RD&D program that would provide a full-scale demonstration of the complete separations and waste production flowsheet within 20 years.

  14. Sterically-controlled intermolecular Friedel-Crafts acylation with twisted amides via selective N-C cleavage under mild conditions.

    Science.gov (United States)

    Liu, Yongmei; Meng, Guangrong; Liu, Ruzhang; Szostak, Michal

    2016-05-21

    Highly chemoselective Friedel-Crafts acylation with twisted amides under mild conditions is reported for the first time. The reaction shows high functional group tolerance, obviating the need for preformed sensitive organometallic reagents and expensive transition metal catalysts. The high reactivity of amides is switched on by ground-state steric distortion to disrupt the amide bond nN→πCO* resonance as a critical design feature. Conceptually, this new acid-promoted mechanism of twisted amides provides direct access to bench-stable acylating reagents under mild, metal-free conditions. PMID:27139813

  15. Merging Photoredox with Palladium Catalysis: Decarboxylative ortho-Acylation of Acetanilides with α-Oxocarboxylic Acids under Mild Reaction Conditions.

    Science.gov (United States)

    Zhou, Chao; Li, Pinhua; Zhu, Xianjin; Wang, Lei

    2015-12-18

    A room temperature decarboxylative ortho-acylation of acetanilides with α-oxocarboxylic acids has been developed via a novel Eosin Y with Pd dual catalytic system. This dual catalytic reaction shows a broad substrate scope and good functional group tolerance, and an array of ortho-acylacetanilides can be afforded in high yields under mild conditions.

  16. Acyl-acyl carrier protein thioesterase activity from sunflower (Helianthus annuus L.) seeds.

    Science.gov (United States)

    Martínez-Force, E; Cantisán, S; Serrano-Vega, M J; Garcés, R

    2000-10-01

    During sunflower (Helianthus annuus L.) seed formation there was an active period of lipid biosynthesis between 12 and 28 days after flowering (DAF). The maximum in-vitro acyl-acyl carrier protein (ACP) thioesterase activities (EC 3.1.2.14) were found at 15 DAF, preceding the largest accumulation of lipid in the seed. Data from the apparent kinetic parameters, Vmax and Km, from seeds of 15 and 30 DAF, showed that changes in acyl-ACP thioesterase activity are not only quantitative, but also qualitative, since, although the preferred substrate was always oleoyl-ACP, the affinity for palmitoyl-ACP decreased, whereas that for stearoyl-ACP increased with seed maturation. Bisubstrate assays carried out at 30 DAF seemed to indicate that the total activity found in mature seeds is due to a single enzyme with 100/75/15 affinity for oleoyl-ACP/stearoyl-ACP/ palmitoyl-ACP. In contrast, at 15 DAF, enzymatic data together with partial sequences from cDNAs indicated the presence of at least two enzymes with different properties, a FatA-like thioesterase, with a high affinity for oleoyl-ACP, plus a FatB-like enzyme, with preference for long-chain saturated fatty acids, both being expressed during the active lipid biosynthesis period. Competition assays carried out with CAS-5, a mutant with a higher content of palmitic acid in the seed oil, indicated that a modified FatA-type thioesterase is involved in the mutant phenotype.

  17. Polymorphism of CRISPR shows separated natural groupings of Shigella subtypes and evidence of horizontal transfer of CRISPR.

    Science.gov (United States)

    Yang, Chaojie; Li, Peng; Su, Wenli; Li, Hao; Liu, Hongbo; Yang, Guang; Xie, Jing; Yi, Shengjie; Wang, Jian; Cui, Xianyan; Wu, Zhihao; Wang, Ligui; Hao, Rongzhang; Jia, Leili; Qiu, Shaofu; Song, Hongbin

    2015-01-01

    Clustered, regularly interspaced, short palindromic repeats (CRISPR) act as an adaptive RNA-mediated immune mechanism in bacteria. They can also be used for identification and evolutionary studies based on polymorphisms within the CRISPR locus. We amplified and analyzed 6 CRISPR loci from 237 Shigella strains belonging to the 4 species groups, as well as 13 Escherichia coli strains. The CRISPR-associated (cas) gene sequence arrays of these strains were screened and compared. The CRISPR sequences from Shigella were conserved among subtypes, suggesting that CRISPR may represent a new identification tool for the detection and discrimination of Shigella species. Secondary structure analysis showed a different stem-loop structure at the terminal repeat, suggesting a distinct recognition mechanism in the formation of crRNA. In addition, the presence of "self-target" spacers and polymorphisms within CRISPR in Shigella indicated a selective pressure for inhibition of this system, which has the potential to damage "self DNA." Homology analysis of spacers showed that CRISPR might be involved in the regulation of virulence transmission. Phylogenetic analysis based on CRISPR sequences from Shigella and E. coli indicated that although phenotypic properties maintain convergent evolution, the 4 Shigella species do not represent natural groupings. Surprisingly, comparative analysis of Shigella repeats with other species provided new evidence for CRISPR horizontal transfer. Our results suggested that CRISPR analysis is applicable for the detection of Shigella species and for investigation of evolutionary relationships.

  18. Experimental and theoretical rearrangement of N-acyl-2,2-dimethylaziridines in acidic medium

    Indian Academy of Sciences (India)

    Madiha Kamoun Mhiri; Firas Aboumessaad; Mohamed Lotfi Efrit; Youssef Arfaoui; Néji Besbes

    2016-02-01

    The acid isomerization of N-acyl-2,2-dimethylaziridines 1 in concentrated sulfuric acid at room temperature leads to oxazolines 2 but the neutral hydrolysis of 1 in pure water at room temperature leads to amidoalcohols 3. However, the use of aqueous solutions of H2SO4 at different concentrations at room temperature leads to a mixture of oxazolines 2, amidoalcohols 3 and allylamides 4 with yields depending on the acidity of the medium and the nature of the acyl group. A mechanism has been suggested to explain the formation of these three products. DFT calculations employing the Gaussian 09 program with DFT/B3LYP methods and 6-311++G(2d,2p) basis set were carried out which gave the most stable geometry as well as their atomic charge distributions of compounds 1-4.

  19. Thermodynamics of ligand binding to acyl-coenzyme A binding protein studied by titration calorimetry

    DEFF Research Database (Denmark)

    Færgeman, Nils J.; Sigurskjold, B W; Kragelund, B B;

    1996-01-01

    Ligand binding to recombinant bovine acyl-CoA binding protein (ACBP) was examined using isothermal microcalorimetry. Microcalorimetric measurements confirm that the binding affinity of acyl-CoA esters for ACBP is strongly dependent on the length of the acyl chain with a clear preference for acyl-...

  20. Evolution of the acyl-CoA binding protein (ACBP)

    DEFF Research Database (Denmark)

    Burton, Mark; Rose, Timothy M; Faergeman, Nils J;

    2005-01-01

    Acyl-CoA-binding protein (ACBP) is a 10 kDa protein that binds C12-C22 acyl-CoA esters with high affinity. In vitro and in vivo experiments suggest that it is involved in multiple cellular tasks including modulation of fatty acid biosynthesis, enzyme regulation, regulation of the intracellular ac......-specific paralogues have evolved altered functions. The appearance of ACBP very early on in evolution points towards a fundamental role of ACBP in acyl-CoA metabolism, including ceramide synthesis and in signalling....

  1. On Hermitian separability of the next-to-leading order BFKL kernel for the adjoint representation of the gauge group in the planar N = 4 SYM

    Energy Technology Data Exchange (ETDEWEB)

    Fadin, V.S. [Budker Institute of Nuclear Physics, SD RAS, Novosibirsk (Russian Federation); Novosibirsk State University, Novosibirsk (Russian Federation); Fiore, R. [Universita della Calabria, Dipartimento di Fisica, Cosenza (Italy); Istituto Nazionale di Fisica, Nucleare Gruppo Collegato di Cosenza (Italy)

    2016-05-15

    We analyze a modification of the BFKL kernel for the adjoint representation of the color group in the maximally supersymmetric (N = 4) Yang-Mills theory in the limit of a large number of colors, related to the modification of the eigenvalues of the kernel suggested by Bondarenko and Prygarin in order to obtain Hermitian separability of the eigenvalues. We restore the modified kernel in the momentum space. It turns out that the modification is related only to the real part of the kernel and that the correction to the kernel cannot be presented by a single analytic function in the entire momentum region, which contradicts the known properties of the kernel. (orig.)

  2. On Hermitian separability of the next-to-leading order BFKL kernel for the adjoint representation of the gauge group in the planar N=4 SYM

    Science.gov (United States)

    Fadin, V. S.; Fiore, R.

    2016-05-01

    We analyze a modification of the BFKL kernel for the adjoint representation of the color group in the maximally supersymmetric (N=4) Yang-Mills theory in the limit of a large number of colors, related to the modification of the eigenvalues of the kernel suggested by Bondarenko and Prygarin in order to obtain Hermitian separability of the eigenvalues. We restore the modified kernel in the momentum space. It turns out that the modification is related only to the real part of the kernel and that the correction to the kernel cannot be presented by a single analytic function in the entire momentum region, which contradicts the known properties of the kernel.

  3. A New Acylated Flavonoid from Anaphalis aureo-punctata

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    A new acylated tlavonoid glycoside, 3-O-kaempferol-3-O-acetyl-6-O-(P-coumaroyl)-β-D-glucopyranoside 1 was isolated from the whole plant of Anaphalis aureo-punctata. The structure was established by spectral methods.

  4. Regioselective self-acylating cyclodextrins in organic solvent

    OpenAIRE

    Eunae Cho; Deokgyu Yun; Daham Jeong; Jieun Im; Hyunki Kim; Dindulkar, Someshwar D.; Youngjin Choi; Seunho Jung

    2016-01-01

    Amphiphilic cyclodextrins have been synthesized with self-acylating reaction using vinyl esters in dimethylformamide. In the present study no base, catalyst, or enzyme was used, and the structural analyses using thin layer chromatography, nuclear magnetic resonance spectroscopy and mass spectrometry show that the cyclodextrin is substituted preferentially by one acyl moiety at the C2 position of the glucose unit, suggesting that cyclodextrin functions as a regioselective catalytic carbohydrat...

  5. Arabidopsis acyl-acyl carrier protein synthetase AAE15 with medium chain fatty acid specificity is functional in cyanobacteria

    OpenAIRE

    Kaczmarzyk, Danuta; Hudson, Elton P.; Fulda, Martin

    2016-01-01

    Cyanobacteria are potential hosts for the biosynthesis of oleochemical compounds. The metabolic precursors for such compounds are fatty acids and their derivatives, which require chemical activation to become substrates in further conversion steps. We characterized the acyl activating enzyme AAE15 of Arabidopsis encoded by At4g14070, which is a homologue of a cyanobacterial acyl-ACP synthetase (AAS). We expressed AAE15 in insect cells and demonstrated its AAS activity with medium chain fatty ...

  6. Yeast acyl-CoA-binding protein: acyl-CoA-binding affinity and effect on intracellular acyl-CoA pool size

    DEFF Research Database (Denmark)

    Knudsen, J; Faergeman, N J; Skøtt, H;

    1994-01-01

    Acyl-CoA-binding protein (ACBP) is a 10 kDa protein characterized in vertebrates. We have isolated two ACBP homologues from the yeast Saccharomyces carlsbergensis, named yeast ACBP types 1 and 2. Both proteins contain 86 amino acid residues and are identical except for four conservative substitut...... resulted in a significant expansion of the intracellular acyl-CoA pool. Finally, Southern-blotting analysis of the two genes encoding ACBP types 1 and 2 in S. carlsbergensis strongly indicated that this species is a hybrid between S. cerevisiae and Saccharomyces monacensis....

  7. 压缩感知分组分离语音增强%Speech enhancement based on group-separable compressed sensing

    Institute of Scientific and Technical Information of China (English)

    宁矿凤; 王景芳

    2014-01-01

    压缩感知(Compressive Sensing,CS)是一种基于信号稀疏性的采样方法,可以有效提取信号中所包含的信息。提出了一种分组分离压缩感知语音增强新算法。算法利用语音在离散快速傅里叶变换(Fast Fourier Transform, FFT)域下的稀疏性,设计复域观测矩阵与软阈值对带噪语音进行压缩测量与去噪,通过可分组分离逼近稀疏重建(Sparse Reconstruction by Separable Approximation,SpaRSA)算法恢复语音信号,实现语音增强。实验表明:该算法对含噪信号压缩重构,信噪比幅度较大提高,能更有效地抑制背景噪声。%Compressed Sensing(CS)which is a signal sparsity-based sampling method, can effectively extract the infor-mation contained in the signal. A new method is designed for noisy speech enhancement based on the grouping separation of compressed sensing. Speech sparse expression is used in discrete Fast Fourier Transform(FFT)domain. The algorithm can implement compression measurement and denoising in noisy speech by the design of the complex domain observation matrix and soft threshold. Sparse Reconstruction by Separable Approximation, SpaRSA algorithm is used to restore the speech signal, to achieve speech enhancement. The experiments show that the denoising signal can be compressed and recon-structed for noise signal compression refactoring. The signal-to-noise ratio can be improved greatly. The background noise can be more effectively suppressed.

  8. Enhanced production of branched-chain fatty acids by replacing β-ketoacyl-(acyl-carrier-protein) synthase III (FabH).

    Science.gov (United States)

    Jiang, Wen; Jiang, Yanfang; Bentley, Gayle J; Liu, Di; Xiao, Yi; Zhang, Fuzhong

    2015-08-01

    Branched-chain fatty acids (BCFAs) are important precursors for the production of advanced biofuels with improved cold-flow properties. Previous efforts in engineering type II fatty acid synthase (FAS) for BCFA production suffered from low titers and/or the co-production of a large amount of straight-chain fatty acids (SCFAs), making it nearly impossible for further conversion of BCFAs to branched biofuels. Synthesis of both SCFAs and BCFAs requires FabH, the only β-ketoacyl-(acyl-carrier-protein) synthase in Escherichia coli that catalyzes the initial condensation reaction between malonyl-ACP and a short-chain acyl-CoA. In this study, we demonstrated that replacement of the acetyl-CoA-specific E. coli FabH with a branched-chain-acyl-CoA-specific FabH directed the flux to the synthesis of BCFAs, resulting in a significant enhancement in BCFA titer compared to a strain containing both acetyl-CoA- and branched-chain-acyl-CoA-specific FabHs. We further demonstrated that the composition of BCFAs can be tuned by engineering the upstream pathway to control the supply of different branched-chain acyl-CoAs, leading to the production either even-chain-iso-, odd-chain-iso-, or odd-chain-anteiso-BCFAs separately. Overall, the top-performing strain from this study produced BCFAs at 126 mg/L, comprising 52% of the total free fatty acids. PMID:25788017

  9. Characterization of the structure and immunostimulatory activity of a vaccine adjuvant, de-O-acylated lipooligosaccharide.

    Directory of Open Access Journals (Sweden)

    Ji Eun Han

    Full Text Available Lipopolysaccharide (LPS is a major component of the outer membrane of Gram-negative bacteria. LPS elicits strong immunopathological responses during bacterial infection, and the lipid A moiety of LPS is responsible for this immunostimulatory activity. Lipid A exerts its biological activity by sending signals via TLR4 present on immune cells, and TLR4 agonists have been a target for vaccine adjuvant. Previously, we demonstrated an adjuvant activity of deacylated lipooligosaccharide (dLOS to viral and bacterial antigens. In this study, we characterized the chemical structure of dLOS and evaluated its immunostimulatory activity on mouse and human immune cells in comparison with monophosphoryl lipid A (MPL. dLOS consists of the R3-type core, a glucosamine disaccharide with two phosphate groups, and two N-linked acyl groups [corrected], and two N-linked acyl groups. dLOS was similar to MPL in induction of cytokine production in mouse peritoneal macrophages, but was a more potent activator in human monocytes and dendritic cells (DCs. Results of an analysis of allogeneic T cell responses revealed that dLOS induces Th1, Th2, and Th17-type immune responses in a dose-dependent manner. The immunostimulatory activities of dLOS were completely abrogated in TLR4(-/- mice, which confirms its TLR4-dependency. These results suggest that in the presence of the core oligosaccharide, O-linked acyl groups of LPS are dispensable for activating the TLR4 signaling pathway. dLOS did not cause any pathological effects or death at 0.25, 0.5, or 1 mg per kg body weight in mice in the acute toxicity tests. This result suggests that dLOS has a low toxicity. dLOS should be considered for further development as a safe and effective adjuvant for human vaccines.

  10. On Hermitian separability of the next-to-leading order BFKL kernel for the adjoint representation of the gauge group in the planar N = 4 SYM

    CERN Document Server

    Fadin, V S

    2015-01-01

    We analyze a modification of the BFKL kernel for the adjoint representation of the colour group in the maximally supersymmetric (N=4) Yang-Mills theory in the limit of a large number of colours, related to the modification of the eigenvalues of the kernel suggested by S. Bondarenko and A. Prygarin in order to reach the Hermitian separability of the eigenvalues. We restore the modified kernel in the momentum space. It turns out that the modification is related only to the real part of the kernel and that the correction to the kernel can not be presented by a single analytic function in the entire momentum region, which contradicts the known properties of the kernel.

  11. Crystallization of the C-terminal domain of the mouse brain cytosolic long-chain acyl-CoA thioesterase

    Energy Technology Data Exchange (ETDEWEB)

    Serek, Robert; Forwood, Jade K. [School of Molecular and Microbial Sciences, University of Queensland, Brisbane, Queensland 4072 (Australia); Hume, David A. [School of Molecular and Microbial Sciences, University of Queensland, Brisbane, Queensland 4072 (Australia); Institute for Molecular Bioscience, University of Queensland, Brisbane, Queensland 4072 (Australia); Cooperative Research Centre for Chronic Inflammatory Diseases, University of Queensland, Brisbane, Queensland 4072 (Australia); Special Research Centre for Functional and Applied Genomics, University of Queensland, Brisbane, Queensland 4072 (Australia); Martin, Jennifer L.; Kobe, Bostjan, E-mail: b.kobe@uq.edu.au [School of Molecular and Microbial Sciences, University of Queensland, Brisbane, Queensland 4072 (Australia); Institute for Molecular Bioscience, University of Queensland, Brisbane, Queensland 4072 (Australia); Special Research Centre for Functional and Applied Genomics, University of Queensland, Brisbane, Queensland 4072 (Australia)

    2006-02-01

    The C-terminal domain of the mouse long-chain acyl-CoA thioesterase has been expressed in bacteria and crystallized by vapour diffusion. The crystals diffract to 2.4 Å resolution. The mammalian long-chain acyl-CoA thioesterase, the enzyme that catalyses the hydrolysis of acyl-CoAs to free fatty acids, contains two fused 4HBT (4-hydroxybenzoyl-CoA thioesterase) motifs. The C-terminal domain of the mouse long-chain acyl-CoA thioesterase (Acot7) has been expressed in bacteria and crystallized. The crystals were obtained by vapour diffusion using PEG 2000 MME as precipitant at pH 7.0 and 290 K. The crystals have the symmetry of space group R32 (unit-cell parameters a = b = 136.83, c = 99.82 Å, γ = 120°). Two molecules are expected in the asymmetric unit. The crystals diffract to 2.4 Å resolution using the laboratory X-ray source and are suitable for crystal structure determination.

  12. Ontogenic development of the fatty acyl chain composition of the turkey (Meleagris gallopavo) pectoralis superficialis muscle membranes: an allometric approach.

    Science.gov (United States)

    Szabó, A; Fébel, Hedvig; Horn, P; Andrássy-Baka, G; Bázár, Gy; Romvári, R

    2006-06-01

    The growth-associated development of the m. pectoralis superficialis (MPS) phospholipid (PL) and triacylglycerol (TAG) fatty acyl (FA) chain composition was determined in BUT8 meat-type turkeys. Samples (3 d, 8, 12, 16 and 20 wk) of each 6 males were analysed by lipid fractionation and subsequent gas chromatography. Results were interpreted on an allometric basis. The MPS mass increased linearly (MPS weight = 0.2787 BW- 123.67; R2 = 0.9935, P<0.001, n = 30). In the total phospholipids 62-63% unsaturated fatty acids were found irrespective of the diet. A negative allometric alteration was found for the total saturated acyl chains (B = -0.012), while a positive value for the calculated unsaturation index (B = 0.026) was obtained. Within the PUFA chains, the n3- n6 balance was markedly changed, on the favour of the n3 fatty acyl chains, namely competitive allometric trends were found for the total n3 (B = 0.087) and n6 (B = 0.032) fatty acid groups. The alterations of the TAG FA chain composition were diet-dependent. The serum creatine kinase activity increased by over one class of magnitude during the trial. The allometric approach was found to be powerful in the characterization of the basic, non diet-dependent ontogenic alterations of the phospholipid fatty acyl chain composition.

  13. Acyl chain length and charge effect on Tamoxifen-lipid model membrane interactions

    Science.gov (United States)

    Bilge, Duygu; Kazanci, Nadide; Severcan, Feride

    2013-05-01

    Tamoxifen (TAM), which is an antiestrogenic agent, is widely used during chemotherapy of breast, pancreas, brain and liver cancers. In this study, TAM and model membrane interactions in the form of multilamellar vesicles (MLVs) were studied for lipids containing different acyl chain length and different charge status as a function of different TAM (1, 6, 9 and 15 mol%) concentrations. Zwitterionic lipids namely dipalmitoyl phosphatidylcholine (DPPC), and dimyristoylphosphatidylcholine (DMPC) lipids were used to see the acyl chain length effect and anionic dipalmitoyl phosphtidylglycerol (DPPG) lipid was used to see the charge effect. For this purpose Fourier transform-infrared (FTIR) spectroscopic and differential scanning calorimetric (DSC) techniques have been conducted. For zwitterionic lipid, concentration dependent different action of TAM was observed both in the gel and liquid crystalline phases by significantly increasing the lipid order and decreasing the dynamics for 1 mol% TAM, while decreasing the lipid order and increasing the dynamics of the lipids for higher concentrations (6, 9 and 15 mol%). However, different than neutral lipids, the dynamics and disorder of DPPG liposome increased for all TAM concentrations. The interactions between TAM and head group of multilamellar liposomes was monitored by analyzing the Cdbnd O stretching and PO2- antisymmetric double bond stretching bands. Increasing Tamoxifen concentrations led to a dehydration around these functional groups in the polar part of the lipids. DSC studies showed that for all types of lipids, TAM eliminates the pre-transition, shifts the main phase transition to lower temperatures and broadened the phase transition curve. The results indicate that not the acyl chain length but the charge status of the polar head group induces different effects on lipid membranes order and dynamics.

  14. Trapping of the Enoyl-Acyl Carrier Protein Reductase-Acyl Carrier Protein Interaction.

    Science.gov (United States)

    Tallorin, Lorillee; Finzel, Kara; Nguyen, Quynh G; Beld, Joris; La Clair, James J; Burkart, Michael D

    2016-03-30

    An ideal target for metabolic engineering, fatty acid biosynthesis remains poorly understood on a molecular level. These carrier protein-dependent pathways require fundamental protein-protein interactions to guide reactivity and processivity, and their control has become one of the major hurdles in successfully adapting these biological machines. Our laboratory has developed methods to prepare acyl carrier proteins (ACPs) loaded with substrate mimetics and cross-linkers to visualize and trap interactions with partner enzymes, and we continue to expand the tools for studying these pathways. We now describe application of the slow-onset, tight-binding inhibitor triclosan to explore the interactions between the type II fatty acid ACP from Escherichia coli, AcpP, and its corresponding enoyl-ACP reductase, FabI. We show that the AcpP-triclosan complex demonstrates nM binding, inhibits in vitro activity, and can be used to isolate FabI in complex proteomes. PMID:26938266

  15. Ghrelin O-Acyl Transferase: Bridging Ghrelin and Energy Homeostasis

    Directory of Open Access Journals (Sweden)

    Andrew Shlimun

    2011-01-01

    Full Text Available Ghrelin O-acyl transferase (GOAT is a recently identified enzyme responsible for the unique n-acyl modification of ghrelin, a multifunctional metabolic hormone. GOAT structure and activity appears to be conserved from fish to man. Since the acyl modification is critical for most of the biological actions of ghrelin, especially metabolic functions, GOAT emerged as a very important molecule of interest. The research on GOAT is on the rise, and several important results reiterating its significance have been reported. Notable among these discoveries are the identification of GOAT tissue expression patterns, effects on insulin secretion, blood glucose levels, feeding, body weight, and metabolism. Several attempts have been made to design and test synthetic compounds that can modulate endogenous GOAT, which could turn beneficial in favorably regulating whole body energy homeostasis. This paper will focus to provide an update on recent advances in GOAT research and its broader implications in the regulation of energy balance.

  16. Acylation and deacylation mechanism of Helicobacter pylori AmiF formamidase: A computational DFT study

    Science.gov (United States)

    He, Rongxing; Yang, Qinlei; Li, Ming

    2014-04-01

    The acylation and deacylation mechanisms of Helicobacter pylori AmiF formamidase were investigated using DFT method. In the constructed active site, residues Glu60, Glu141 and His167 were taken into account besides Lys133 and Cys166. Calculations provided insight on the details of mechanism and explained crucial roles played by Glu60, Glu141 and His167. For acetylation, we proposed a new stepwise mechanism in which the thiol group first attacks the carbon atom of formamide and produces tetrahedral intermediate. In deacylation, Glu60 activates a water molecule to perform nucleophilic attack and then forms an intermediate, which is different from the usually suggested mechanism.

  17. An Evaluation of Acylated Ghrelin and Obestatin Levels in Childhood Obesity and Their Association with Insulin Resistance, Metabolic Syndrome, and Oxidative Stress

    Science.gov (United States)

    Razzaghy-Azar, Maryam; Nourbakhsh, Mitra; Pourmoteabed, Abdolreza; Nourbakhsh, Mona; Ilbeigi, Davod; Khosravi, Mohsen

    2016-01-01

    Background: Ghrelin is a 28-amino acid peptide with an orexigenic property, which is predominantly produced by the stomach. Acylated ghrelin is the active form of this hormone. Obestatin is a 23-amino acid peptide which is produced by post-translational modification of a protein precursor that also produces ghrelin. Obestatin has the opposite effect of ghrelin on food intake. The aim of this study was to evaluate acylated ghrelin and obestatin levels and their ratio in obese and normal-weight children and adolescents, and their association with metabolic syndrome (MetS) parameters. Methods: Serum acyl-ghrelin, obestatin, leptin, insulin, fasting plasma glucose (FPG), lipid profile, and malondialdehyde (MDA) were evaluated in 73 children and adolescents (42 obese and 31 control). Insulin resistance was calculated by a homeostasis model assessment of insulin resistance (HOMA-IR). MetS was determined according to IDF criteria. Results: Acyl-ghrelin levels were significantly lower in obese subjects compared to the control group and lower in obese children with MetS compared to obese subjects without MetS. Obestatin was significantly higher in obese subjects compared to that of the control, but it did not differ significantly among those with or without MetS. Acyl-ghrelin to obestatin ratio was significantly lower in obese subjects compared to that in normal subjects. Acyl-ghrelin showed significant negative and obestatin showed significant positive correlations with body mass index (BMI), BMI Z-score, leptin, insulin, and HOMA-IR. Acyl-ghrelin had a significant negative correlation with MDA as an index of oxidative stress. Conclusion: Ghrelin is decreased and obestatin is elevated in obesity. Both of these hormones are associated with insulin resistance, and ghrelin is associated with oxidative stress. The balance between ghrelin and obestatin seems to be disturbed in obesity. PMID:27348010

  18. Infrared and Fluorescence Spectroscopic Investigations of the Acyl Surface Modification of Hydrogel Beads for the Deposition of a Phospholipid Coating.

    Science.gov (United States)

    Grossutti, Michael; Seenath, Ryan; Lipkowski, Jacek

    2015-10-27

    The scaffolded vesicle has been employed as an alternative means of developing natural model membranes and envisioned as a potential nutraceutical transporter. Furthering the research of the scaffolded vesicle system, a nucleophilic substitution reaction was implemented to form an ester linkage between palmitate and terminal hydroxyl groups of dextran in order to hydrophobically modify the hydrogel scaffold. An average tilt angle of 38° of the hydrophobic palmitate modifying layer on the surface of the hydrogel was determined from dichroic ratios obtained from infrared spectra collected in the attenuated total reflection (ATR) configuration. ATR-IR studies of the DMPC-coated acylated hydrogel demonstrated that the hydrocarbon chains of the DMPC coating was similar to those of the DMPC bilayers and that the underlying palmitate layer had a negligible effect on the average tilt angle (26°) of the DMPC coating. The permeability of this acylated hydrogel was investigated with fluorescence spectroscopy and the terbium/dipicolinic acid assay. The hydrophobic modification on the surface of the hydrogel bead allowed for an efficient deposition of a DMPC layer that served as an impermeable barrier to terbium efflux. About 72% of DMPC-coated acylated hydrogel beads showed ideal barrier properties. The remaining 28% were leaking, but the half-life of terbium efflux of the DMPC-coated acylated hydrogel was increasing, and the total amount of leaked terbium was decreasing with the incubation time. The half-life time and the retention were considered a marked improvement relative to past scaffolded vesicle preparations. The process of acylating hydrogel beads for efficient DMPC deposition has been identified as another viable method for controlling the permeability of the scaffolded vesicle.

  19. Caveolar fatty acids and acylation of caveolin-1.

    Directory of Open Access Journals (Sweden)

    Qian Cai

    Full Text Available PURPOSE: Caveolae are cholesterol and sphingolipids rich subcellular domains on plasma membrane. Caveolae contain a variety of signaling proteins which provide platforms for signaling transduction. In addition to enriched with cholesterol and sphingolipids, caveolae also contain a variety of fatty acids. It has been well-established that acylation of protein plays a pivotal role in subcellular location including targeting to caveolae. However, the fatty acid compositions of caveolae and the type of acylation of caveolar proteins remain largely unknown. In this study, we investigated the fatty acids in caveolae and caveolin-1 bound fatty acids. METHODS: Caveolae were isolated from Chinese hamster ovary (CHO cells. The caveolar fatty acids were extracted with Folch reagent, methyl esterificated with BF3, and analyzed by gas chromatograph-mass spectrometer (GC/MS. The caveolin-1 bound fatty acids were immunoprecipitated by anti-caveolin-1 IgG and analyzed with GC/MS. RESULTS: In contrast to the whole CHO cell lysate which contained a variety of fatty acids, caveolae mainly contained three types of fatty acids, 0.48 µg palmitic acid, 0.61 µg stearic acid and 0.83 µg oleic acid/caveolae preparation/5 × 10(7 cells. Unexpectedly, GC/MS analysis indicated that caveolin-1 was not acylated by myristic acid; instead, it was acylated by palmitic acid and stearic acid. CONCLUSION: Caveolae contained a special set of fatty acids, highly enriched with saturated fatty acids, and caveolin-1 was acylated by palmitic acid and stearic acid. The unique fatty acid compositions of caveolae and acylation of caveolin-1 may be important for caveolae formation and for maintaining the function of caveolae.

  20. Identification of unusual phospholipid fatty acyl compositions of Acanthamoeba castellanii.

    Directory of Open Access Journals (Sweden)

    Marta Palusinska-Szysz

    Full Text Available Acanthamoeba are opportunistic protozoan pathogens that may lead to sight-threatening keratitis and fatal granulomatous encephalitis. The successful prognosis requires early diagnosis and differentiation of pathogenic Acanthamoeba followed by aggressive treatment regimen. The plasma membrane of Acanthamoeba consists of 25% phospholipids (PL. The presence of C20 and, recently reported, 28- and 30-carbon fatty acyl residues is characteristic of amoeba PL. A detailed knowledge about this unusual PL composition could help to differentiate Acanthamoeba from other parasites, e.g. bacteria and develop more efficient treatment strategies. Therefore, the detailed PL composition of Acanthamoeba castellanii was investigated by 31P nuclear magnetic resonance spectroscopy, thin-layer chromatography, gas chromatography, high performance liquid chromatography and liquid chromatography-mass spectrometry. Normal and reversed phase liquid chromatography coupled with mass spectrometric detection was used for detailed characterization of the fatty acyl composition of each detected PL. The most abundant fatty acyl residues in each PL class were octadecanoyl (18∶0, octadecenoyl (18∶1 Δ9 and hexadecanoyl (16∶0. However, some selected PLs contained also very long fatty acyl chains: the presence of 28- and 30-carbon fatty acyl residues was confirmed in phosphatidylethanolamine (PE, phosphatidylserine, phosphatidic acid and cardiolipin. The majority of these fatty acyl residues were also identified in PE that resulted in the following composition: 28∶1/20∶2, 30∶2/18∶1, 28∶0/20∶2, 30∶2/20∶4 and 30∶3/20∶3. The PL of amoebae are significantly different in comparison to other cells: we describe here for the first time unusual, very long chain fatty acids with Δ5-unsaturation (30∶35,21,24 and 30∶221,24 localized exclusively in specific phospholipid classes of A. castellanii protozoa that could serve as specific biomarkers for the presence of

  1. Phase behavior and nanoscale structure of phospholipid membranes incorporated with acylated C-14-peptides

    DEFF Research Database (Denmark)

    Pedersen, T.B.; Kaasgaard, Thomas; Jensen, M.O.;

    2005-01-01

    The thermotropic phase behavior and lateral structure of dipalmitoylphosphatidylcholine (DPPC) lipid bilayers containing an acylated peptide has been characterized by differential scanning calorimetry (DSC) on vesicles and atomic force microscopy (AFM) on mica-supported bilayers. The acylated...

  2. Fluorescently labelled bovine acyl-CoA-binding protein acting as an acyl-CoA sensor: interaction with CoA and acyl-CoA esters and its use in measuring free acyl-CoA esters and non-esterified fatty acids

    DEFF Research Database (Denmark)

    Wadum, M.C.; Villadsen, J.K.; Feddersen, S.;

    2002-01-01

    Long-chain acyl-CoA esters are key metabolites in lipid synthesis and b-oxidation but, at the same time, are important regulators of intermediate metabolism, insulin secretion, vesicular trafficking and gene expression. Key tools in studying the regulatory functions of acyl-CoA esters are reliable...... methods for the determination of free acyl-CoA concentrations. No such method is presently available. In the present study, we describe the synthesis of two acyl-CoA sensors for measuring free acyl-CoA concentrations using acyl-CoA-binding protein as a scaffold. Met24 and Ala53 of bovine acyl......-CoA-binding protein were replaced by cysteine residues, which were covalently modified with 6-bromoacetyl-2-dimethylaminonaphthalene to make the two fluorescent acyl-CoA indicators (FACIs) FACI-24 and FACI-53. FACI-24 and FACI-53 showed fluorescence emission maximum at 510 and 525nm respectively, in the absence of...

  3. Studies on acylation of lysolecithin in chicken intestine

    International Nuclear Information System (INIS)

    The enzymatic acylation of lysolecithin to lecithin is shown to occur in the brush border-free particulate fraction of the small intestines of neonatal chicken. It requires ATP, coenzyme A and Mg2+ or Mn2+ for maximal activity. The system is specific for oleic acid. The fatty acid composition at the α-position of lysolecithin does not seem to influence the rate of acylation. The fatty acid incorporated into lysolecithin is shown to occupy exclusively, the β-position. [32P]lecithin and [1-14C]oleic acid has been used as tracers in the studies. (author)

  4. Funktionelle Analysen zum Acyl-CoA-Bindeprotein (ACBP)

    OpenAIRE

    Klausz, Katja

    2009-01-01

    Das Fettsäurebindeprotein mit der höchsten Spezifität für langkettige, Acyl-CoA ist das Acyl-CoA-Bindeprotein (ACBP). Der Vergleich transgener, ACBP-überexprimierender Ratten mit Wildtypen nach einmonatiger Fütterung einer Niedrig- (LFD) bzw. Hochfettdiät (HFD) zeigt bei den transgenen Tieren höhere Konzentrationen an freien Fettsäuren und Triglyzeriden, sowie veränderte Glukose- und Insulinwerte. Zudem führt die ACBP-Überexpression unter LFD in der Leber zur verringerten SREBP-1c- und L-FABP...

  5. Acyl-CoA Dehydrogenase 9 Is Required for the Biogenesis of Oxidative Phosphorylation Complex I

    NARCIS (Netherlands)

    J. Nouws; L. Nijtmans; S.M. Houten; M. Brand; M. Huynen; H. Venselaar; S. Hoefs; J. Gloerich; J. Kronick; T. Hutchin; P. Willems; R. Rodenburg; R. Wanders; L. van den Heuvel; J. Smeitink; R.O. Vogel

    2010-01-01

    Acyl-CoA dehydrogenase 9 (ACAD9) is a recently identified member of the acyl-CoA dehydrogenase family. It closely resembles very long-chain acyl-CoA dehydrogenase (VLCAD), involved in mitochondria! (3 oxidation of long-chain fatty acids. Contrary to its previously proposed involvement in fatty acid

  6. Influence of acylation on the adsorption of GLP-2 to hydrophobic surfaces

    DEFF Research Database (Denmark)

    Pinholt, Charlotte; Kapp, Sebastian J; Bukrinsky, Jens T;

    2013-01-01

    of this work was to study the effect of acylation on the adsorption of GLP-2 from aqueous solution to a hydrophobic surface by comparing the adsorption of the 3766 Da GLP-2 with that of a GLP-2 variant acylated with a 16-carbon fatty acid chain through a ß-alanine linker. Adsorption of GLP-2 and acylated GLP-2...

  7. Separations of flavan-3-ols and dimeric proanthocyanidins by capillary electrophoresis.

    Science.gov (United States)

    Kreimeyer, J; Petereit, F; Nahrstedt, A

    1998-02-01

    Micellar electrokinetic capillary chromatography (MECC), using a phosphate buffer pH 7.0 and sodium dodecyl sulfate as the surfactant, was found suitable for the separation of structurally similar flavan-3-ols and related dimeric proanthocyanidins. A total of 20 substances has been tested, 17 of which were successfully separated simultaneously in less than 7 minutes. Retention of the investigated compounds by the SDS micelles is affected by (i) the stereochemistry of the heterocycle of the flavan-3-ol skeleton, (ii) the molecular size, the number and position of free phenolic hydroxy groups, and (iii) the type of acyl residues attached at the C-3 hydroxy function. The method was successfully applied to the phytochemical analysis of tannin enriched extracts of Cistus incanus L. ssp. incanus and C. salvifolius L. (Cistaceae), two traditionally used medicinal plants. PMID:17253220

  8. A new acylated isoflavone glucoside from Pterocarpus santalinus.

    Science.gov (United States)

    Krishnaveni, K S; Srinivasa Rao, J V

    2000-09-01

    Phytochemical investigation on the constituents of heartwood of Pterocarpus santalinus resulted in the isolation of a new acylated isoflavone glucoside. The structure of the new compound was elucidated on the basis of spectral studies as 4',5-dihydroxy-7-O-methyl isoflavone 3'-O-D-(3''-E-cinnamoyl)glucoside. PMID:10993243

  9. Acyl migration kinetics of vegetable oil 1,2-diacylglycerols

    Science.gov (United States)

    The acyl migration kinetics of long-chain 1,2-diacylglycerol (1,2-DAG) to form 1,3-diacylglycerol (1,3-DAG) over the temperature range of 25 to 80 degrees Celsius were examined using proton NMR spectroscopy. The 1,2-DAG mole fraction of 0.32 at equilibrium was found to be insensitive to temperature...

  10. Enzymatic process for acylation of resveratrol at position 3

    OpenAIRE

    Torres, Pamela; Plou Gasca, Francisco José; Ballesteros Olmo, Antonio

    2008-01-01

    [EN] Enzymatic procedure for the regioselective acylation at position 3 of resveratrol utilising a vinyl ester and specific fungal and bacterial lipases, immobilised, as biocatalyst. The lipases utilised in said procedure come from bacteria or fungi selected from among Alcaligenes, Pseudomonas or Thermomyces.

  11. Fatty Acyl-CoA Reductase 1 Deficiency

    Directory of Open Access Journals (Sweden)

    Charles N Swisher

    2015-01-01

    Full Text Available Investigators from Erlangen, Germany; Calgary, CA; and Kafranbel, Syria, identified mutations in the gene, fatty acyl-CoA reductase 1 (FAR1 deficiency, adding to three other genes involved in plasmalogen biosynthesis, in two families affected by severe intellectual disability, early-onset epilepsy, microcephaly, congenital cataracts, growth retardation, and spasticity.

  12. Specificity of Acyl-Homoserine Lactone Synthases Examined by Mass Spectrometry

    OpenAIRE

    Gould, Ty A.; Herman, Jake; Krank, Jessica; Robert C. Murphy; Mair E A Churchill

    2006-01-01

    Many gram-negative bacteria produce a specific set of N-acyl-l-homoserine-lactone (AHL) signaling molecules for the purpose of quorum sensing, which is a means of regulating coordinated gene expression in a cell-density-dependent manner. AHLs are produced from acylated acyl-carrier protein (acyl-ACP) and S-adenosyl-l-methionine by the AHL synthase enzyme. The appearance of specific AHLs is due in large part to the intrinsic specificity of the enzyme for subsets of acyl-ACP substrates. Structu...

  13. Ethanol metabolism modifies hepatic protein acylation in mice.

    Directory of Open Access Journals (Sweden)

    Kristofer S Fritz

    Full Text Available Mitochondrial protein acetylation increases in response to chronic ethanol ingestion in mice, and is thought to reduce mitochondrial function and contribute to the pathogenesis of alcoholic liver disease. The mitochondrial deacetylase SIRT3 regulates the acetylation status of several mitochondrial proteins, including those involved in ethanol metabolism. The newly discovered desuccinylase activity of the mitochondrial sirtuin SIRT5 suggests that protein succinylation could be an important post-translational modification regulating mitochondrial metabolism. To assess the possible role of protein succinylation in ethanol metabolism, we surveyed hepatic sub-cellular protein fractions from mice fed a control or ethanol-supplemented diet for succinyl-lysine, as well as acetyl-, propionyl-, and butyryl-lysine post-translational modifications. We found mitochondrial protein propionylation increases, similar to mitochondrial protein acetylation. In contrast, mitochondrial protein succinylation is reduced. These mitochondrial protein modifications appear to be primarily driven by ethanol metabolism, and not by changes in mitochondrial sirtuin levels. Similar trends in acyl modifications were observed in the nucleus. However, comparatively fewer acyl modifications were observed in the cytoplasmic or the microsomal compartments, and were generally unchanged by ethanol metabolism. Using a mass spectrometry proteomics approach, we identified several candidate acetylated, propionylated, and succinylated proteins, which were enriched using antibodies against each modification. Additionally, we identified several acetyl and propionyl lysine residues on the same sites for a number of proteins and supports the idea of the overlapping nature of lysine-specific acylation. Thus, we show that novel post-translational modifications are present in hepatic mitochondrial, nuclear, cytoplasmic, and microsomal compartments and ethanol ingestion, and its associated

  14. Ethanol Metabolism Modifies Hepatic Protein Acylation in Mice

    Science.gov (United States)

    Fritz, Kristofer S.; Green, Michelle F.; Petersen, Dennis R.; Hirschey, Matthew D.

    2013-01-01

    Mitochondrial protein acetylation increases in response to chronic ethanol ingestion in mice, and is thought to reduce mitochondrial function and contribute to the pathogenesis of alcoholic liver disease. The mitochondrial deacetylase SIRT3 regulates the acetylation status of several mitochondrial proteins, including those involved in ethanol metabolism. The newly discovered desuccinylase activity of the mitochondrial sirtuin SIRT5 suggests that protein succinylation could be an important post-translational modification regulating mitochondrial metabolism. To assess the possible role of protein succinylation in ethanol metabolism, we surveyed hepatic sub-cellular protein fractions from mice fed a control or ethanol-supplemented diet for succinyl-lysine, as well as acetyl-, propionyl-, and butyryl-lysine post-translational modifications. We found mitochondrial protein propionylation increases, similar to mitochondrial protein acetylation. In contrast, mitochondrial protein succinylation is reduced. These mitochondrial protein modifications appear to be primarily driven by ethanol metabolism, and not by changes in mitochondrial sirtuin levels. Similar trends in acyl modifications were observed in the nucleus. However, comparatively fewer acyl modifications were observed in the cytoplasmic or the microsomal compartments, and were generally unchanged by ethanol metabolism. Using a mass spectrometry proteomics approach, we identified several candidate acetylated, propionylated, and succinylated proteins, which were enriched using antibodies against each modification. Additionally, we identified several acetyl and propionyl lysine residues on the same sites for a number of proteins and supports the idea of the overlapping nature of lysine-specific acylation. Thus, we show that novel post-translational modifications are present in hepatic mitochondrial, nuclear, cytoplasmic, and microsomal compartments and ethanol ingestion, and its associated metabolism, induce specific

  15. C8-Selective Acylation of Quinoline N-Oxides with α-Oxocarboxylic Acids via Palladium-Catalyzed Regioselective C-H Bond Activation.

    Science.gov (United States)

    Chen, Xiaopei; Cui, Xiuling; Wu, Yangjie

    2016-08-01

    A facile and efficient protocol for palladium-catalyzed C8-selective acylation of quinoline N-oxides with α-oxocarboxylic acids has been developed. In this approach, N-oxide was utilized as a stepping stone for the remote C-H functionalization. The reactions proceeded efficiently under mild reaction conditions with excellent regioselectivity and broad functional group tolerance. PMID:27441527

  16. Hierarchy of N-acylation Sites in Human Insulin Studied by RP-HPLC and Mass Spectrometry

    International Nuclear Information System (INIS)

    Acylation of human insulin was studied using, C/sub 2/ and C/sub 12/ transfer reagents, N-succinimidyl acetate and N-succinimidyl dodecanoate (lauryl) respectively. In general, the acylation reaction was more specific at high pH values (12.00) for the modification of the epsilon-amino group of K/sup 29B/. At pH around 8.5, multiple modifications occurred at other sites, in particular the N-terminal glycine of A-chain (G/sup 1A/). With N-succinimidyl dodecanoate, about 88 percent of the acylation was established to be at the epsilon-amino of K/sup 29B/, as shown using tryptic digestion and identification of the products by mass spectrometry. While with N-succinimidyl acetate, singly acetylated product with acetyl group at the epsilon-amino of K/sup 29B/, as well as doubly modified species containing acetyl group in the epsilon-amino group and the amino-terminal of G/sup 1A/ were produced in equal amounts. The high regiospecificity of modification at the epsilon-amino group, by the C/sub 12/ reagent, is attributed to steric factors. Moreover, the above investigation also highlights the purification regime of singly and doubly acetylated products on RP-HPLC using a shallow gradient, though the difference between two species, in the case of acetyl group, is of 43 Da. The overall results allow us to establish the hierarchy of accessibility of the three amino group; epsilon-amino group K/sup 29B/ is the least hindered and accessible to C/sub 2/ as well as C/sub 12/ reagents, then is the amino group of G/sup 1A/ which is accessible to the C/sub 2/ but not the C/sub 12/ reagent, finally that of F/sup 1B/ is most hindered and accessible to neither. (author)

  17. Quantitation of acyl migration during lipase-catalyzed acidolysis, and of the regioisomers of structured triacylglycerols formed

    DEFF Research Database (Denmark)

    Mu, Huiling; Kurvinen, J.P.; Kallio, H.;

    2001-01-01

    degradation, and ranged from 39.0 to 48.7% and 0.6 to 9.3%, respectively. Quantitation of triacylglycerol molecular species was performed by ammonia negative ion chemical ionization (NICI) mass spectrometry (MS). The proportion of ACN (acyl carbon number) 34 species that contained one C-18 fatty acid and two...... C-8:0, in samples analyzed, varied from 12.5 to 23.2%. The selected regioisomers MLM and MML within the ACN 34 species group were quantified by NICI tandem MS (MS/MS) and were in the range of 97.1 to 98.4% and 1.6 to 2.9%, respectively. There was no correlation between the level of acyl migration...

  18. A Zeolite Imidazolate Framework ZIF-8 Catalyst for Friedel-Crafts Acylation

    Institute of Scientific and Technical Information of China (English)

    LienT.L.NGUYEN; Ky K.A.LE; Nam T.S.PHAN

    2012-01-01

    A zeolite imidazolate framework,ZIF-8,was synthesized and characterized by dynamic laser light scattering,X-ray powder diffraction,scanning electron microscopy,transmission electron microscopy,thermogravimetric analysis,Fourier transform infrared,atomic absorption spectrophotometry,and nitrogen adsorption measurements.The ZIF-8 was highly crystalline and porous with a surface area of over 1600 m2/g.Friedel-Crafts acylation of anisole and benzoyl chloride proceeded well in the presence of ZIF-8 (2-6 mol%) without the need for an inert atmosphere.The reaction afforded a selectivity of 93%-95% to the p-isomer.The solid catalyst can be separated from the reaction mixture by simple centrifugation and reused without significant degradation in catalytic activity.There was no leaching of active acid species into the reaction solution.

  19. Acylated glucosylflavones as α-glucosidase inhibitors from Tinospora crispa leaf.

    Science.gov (United States)

    Chang, Chi-Chih; Ho, Sheau Ling; Lee, Shoei-Sheng

    2015-07-01

    The ethanolic extract of Tinospora crispa leaf had shown inhibitory activity toward α-glucosidase. Bioassay guided fractionation and separation of this extract led to the isolation of 17 flavonoids. Among them, four acylated glycosylflavonoids (6, 8, 9, 15) are new compounds. Their structures were elucidated on the basis of spectroscopic analysis. Among the isolated compounds, isovitexin 2″-(E)-p-coumarate (8) showed the best activity against α-glucosidase with an IC50 value of 4.3±1.4μM. However, isoorientin 2″-(E)-p-coumarate (7), the 3'-hydroxylated 8, is much less active (IC50 35.7μM). Such significant difference was rationalized by CAD study on α-glucosidase. PMID:25999202

  20. Silica gel-Supported Palladium Catalyst for the Acyl Sonogashira Reaction

    Energy Technology Data Exchange (ETDEWEB)

    Hossain, Shahin; Park, Jihoon; Park, Minkyu; Jin, Myungjong [Inha Univ., Incheon (Korea, Republic of)

    2013-06-15

    We have demonstrated an efficient and eco-friendly procedure for the synthesis of ynones using silica supported thiol-palladium complex as a recyclable catalyst under copper free mild reaction conditions. The material was synthesized by post grafting of 3-mercaptopropyltrimethoxysilane on amorphous silica and subsequently Pd(II) attached onto thiol groups. This synthetic method has notable advantages because it involves easily available, less costly and produces an easily recyclable catalyst in high yields of the products. The mild reaction conditions encouraged us to further extension for the development of novel multicomponent reactions. Thus we have explained the three component synthesis of pyrazoles in one-pot fashion with good yields. Specifically, this simple procedure for the ynone synthesis and this approach to synthesize N-containing heterocycles may be valuable tool in future. The acyl Sonogashira reaction between acyl chlorides and terminal alkynes is one of the most useful method for the preparation of ynones which are important intermediates to prepare versatile pharmaceutically and biologically active heterocyclic compounds such as pyrroles, pyrazoles, furans, furanones, isoxazoles, pyrimidines, quinolines, indolizidinones.

  1. Acyl-CoA-binding protein (ACBP) can mediate intermembrane acyl-CoA transport and donate acyl-CoA for beta-oxidation and glycerolipid synthesis

    DEFF Research Database (Denmark)

    Rasmussen, J T; Færgeman, Nils J.; Kristiansen, K;

    1994-01-01

    The dissociation constants for octanoyl-CoA, dodecanoyl-CoA and hexadecanoyl-CoA binding to acyl-CoA-binding protein (ACBP) were determined by using titration microcalorimetry. The KD values obtained, (0.24 +/- 0.02) x 10(-6) M, (0.65 +/- 0.2) x 10(-8) M and (0.45 +/- 0.2) x 10(-13) M respectivel...... on a nitrocellulose membrane, and to donate them to beta-oxidation or glycerolipid synthesis in mitochondria or microsomes, respectively....

  2. Lipase-catalyzed biodiesel synthesis with different acyl acceptors

    Directory of Open Access Journals (Sweden)

    Ognjanović Nevena D.

    2008-01-01

    Full Text Available Biodiesel is an alternative fuel for diesel engine that is environmentally acceptable. Conventionally, biodiesel is produced by transesterification of triglycerides and short alcohols in the presence of an acid or an alkaline catalyst. There are several problems associated with this kind of production that can be resolved by using lipase as the biocatalyst. The aim of the present work was to investigate novel acyl acceptors for biodiesel production. 2-Propanol and n-butanol have a less negative effect on lipase stability, and they also improve low temperature properties of the fuel. However, excess alcohol leads to inactivation of the enzyme, and glycerol, a major byproduct, can block the immobilized enzyme, resulting in low enzymatic activity. This problem was solved by using methyl acetate as acyl acceptor. Triacetylglycerol is produced instead of glycerol, and it has no negative effect on the activity of the lipase.

  3. A New Acylated Iridoid Glucoside from Avicennia marina

    Institute of Scientific and Technical Information of China (English)

    Yan FENG; Xiao Ming LI; Xiao Juan DUAN; Bin Gui WANG

    2006-01-01

    A new acylated iridoid glucoside, namely, 2'-O-(5-phenyl-2E, 4E-pentadienoyl)-mussaenosidic acid, was isolated from the aerial parts of the mangrove plant Avicennia marina.The structure of the new compound was established on the basis of various NMR spectroscopic analyses, including 2D NMR techniques (1H-1H COSY, HMQC, and HMBC) and HR-FAB-MS.This compound displayed moderate antioxidant activity.

  4. Synthesis and characterization of new amino acyl-4-thiazolidones

    Directory of Open Access Journals (Sweden)

    Ana Cristina Lima Leite

    2007-04-01

    Full Text Available A series of heterocyclic compounds with a 4-thiazolidone nucleus and amino acyl moiety were synthesized by protection reaction of thiosemicarbazide using the symmetrical anhydride (Boc2O and cyclization with chloroacetic acid under mild conditions. Trifluoroacetic acid was used to obtain 4-thiazolidone and the alpha-amino acid condensation reactions were carried out using strategies for peptide synthesis. The characterization of this new class of compounds was performed using IR and ¹H-NMR spectroscopy.

  5. Glycosyltransferases from oat (Avena) implicated in the acylation of avenacins.

    Science.gov (United States)

    Owatworakit, Amorn; Townsend, Belinda; Louveau, Thomas; Jenner, Helen; Rejzek, Martin; Hughes, Richard K; Saalbach, Gerhard; Qi, Xiaoquan; Bakht, Saleha; Roy, Abhijeet Deb; Mugford, Sam T; Goss, Rebecca J M; Field, Robert A; Osbourn, Anne

    2013-02-01

    Plants produce a huge array of specialized metabolites that have important functions in defense against biotic and abiotic stresses. Many of these compounds are glycosylated by family 1 glycosyltransferases (GTs). Oats (Avena spp.) make root-derived antimicrobial triterpenes (avenacins) that provide protection against soil-borne diseases. The ability to synthesize avenacins has evolved since the divergence of oats from other cereals and grasses. The major avenacin, A-1, is acylated with N-methylanthranilic acid. Previously, we have cloned and characterized three genes for avenacin synthesis (for the triterpene synthase SAD1, a triterpene-modifying cytochrome P450 SAD2, and the serine carboxypeptidase-like acyl transferase SAD7), which form part of a biosynthetic gene cluster. Here, we identify a fourth member of this gene cluster encoding a GT belonging to clade L of family 1 (UGT74H5), and show that this enzyme is an N-methylanthranilic acid O-glucosyltransferase implicated in the synthesis of avenacin A-1. Two other closely related family 1 GTs (UGT74H6 and UGT74H7) are also expressed in oat roots. One of these (UGT74H6) is able to glucosylate both N-methylanthranilic acid and benzoic acid, whereas the function of the other (UGT74H7) remains unknown. Our investigations indicate that UGT74H5 is likely to be key for the generation of the activated acyl donor used by SAD7 in the synthesis of the major avenacin, A-1, whereas UGT74H6 may contribute to the synthesis of other forms of avenacin that are acylated with benzoic acid.

  6. Enzymatic regioselective acylation of nucleosides in biomass-derived 2-methyltetrahydrofuran: kinetic study and enzyme substrate recognition.

    Science.gov (United States)

    Gao, Wen-Li; Li, Ning; Zong, Min-Hua

    2013-03-10

    Enzymatic regioselective acylation of pyrimidine nucleosides was mediated by immobilized lipase from Penicillium expansum in 2-methyltetrahydrofuran (MeTHF), a bio-solvent derived from biomass. Despite of the moderate dissolution ability of MeTHF toward nucleosides, the initial enzymatic reaction rate was much higher in this eco-friendly solvent than in other commonly used organic solvents. This could be explained by the lower apparent activation energy of the enzymatic reaction (24.5 vs. 43.3-57.1kJ/mol) and the higher catalytic efficiency of the enzyme (Vmax/Km, 5.8 vs. 1.1-2.9h(-1)) in MeTHF. The enzymatic acylation of a group of ribonucleosides afforded the desirable 5'-esters with the conversions of 96-99% and 5'-regioselectivities of 96 to >99%. In enzymatic acylation of 2'-deoxynucleosides, however, 5'-regioselectivities showed a clear dependence on the 5-substituents present in the base moiety although the substrate conversions reached >98% within 1-3h. In the cases of 2',3'-dideoxynucleoside analogs, the reaction rate decreased markedly due to the lack of 3'-hydroxyl. PMID:23337886

  7. Metabolism of acyl-lipids in Chlamydomonas reinhardtii.

    Science.gov (United States)

    Li-Beisson, Yonghua; Beisson, Fred; Riekhof, Wayne

    2015-05-01

    Microalgae are emerging platforms for production of a suite of compounds targeting several markets, including food, nutraceuticals, green chemicals, and biofuels. Many of these products, such as biodiesel or polyunsaturated fatty acids (PUFAs), derive from lipid metabolism. A general picture of lipid metabolism in microalgae has been deduced from well characterized pathways of fungi and land plants, but recent advances in molecular and genetic analyses of microalgae have uncovered unique features, pointing out the necessity to study lipid metabolism in microalgae themselves. In the past 10 years, in addition to its traditional role as a model for photosynthetic and flagellar motility processes, Chlamydomonas reinhardtii has emerged as a model organism to study lipid metabolism in green microalgae. Here, after summarizing data on total fatty acid composition, distribution of acyl-lipid classes, and major acyl-lipid molecular species found in C. reinhardtii, we review the current knowledge on the known or putative steps for fatty acid synthesis, glycerolipid desaturation and assembly, membrane lipid turnover, and oil remobilization. A list of characterized or putative enzymes for the major steps of acyl-lipid metabolism in C. reinhardtii is included, and subcellular localizations and phenotypes of associated mutants are discussed. Biogenesis and composition of Chlamydomonas lipid droplets and the potential importance of lipolytic processes in increasing cellular oil content are also highlighted. PMID:25660108

  8. Cardiolipin molecular species with shorter acyl chains accumulate in Saccharomyces cerevisiae mutants lacking the acyl coenzyme A-binding protein Acb1p: new insights into acyl chain remodeling of cardiolipin.

    Science.gov (United States)

    Rijken, Pieter J; Houtkooper, Riekelt H; Akbari, Hana; Brouwers, Jos F; Koorengevel, Martijn C; de Kruijff, Ben; Frentzen, Margrit; Vaz, Frédéric M; de Kroon, Anton I P M

    2009-10-01

    The function of the mitochondrial phospholipid cardiolipin (CL) is thought to depend on its acyl chain composition. The present study aims at a better understanding of the way the CL species profile is established in Saccharomyces cerevisiae by using depletion of the acyl-CoA-binding protein Acb1p as a tool to modulate the cellular acyl chain content. Despite the presence of an intact CL remodeling system, acyl chains shorter than 16 carbon atoms (C16) were found to accumulate in CL in cells lacking Acb1p. Further experiments revealed that Taz1p, a key CL remodeling enzyme, was not responsible for the shortening of CL in the absence of Acb1p. This left de novo CL synthesis as the only possible source of acyl chains shorter than C16 in CL. Experiments in which the substrate specificity of the yeast cardiolipin synthase Crd1p and the acyl chain composition of individual short CL species were investigated, indicated that both CL precursors (i.e. phosphatidylglycerol and CDP-diacylglycerol) contribute to comparable extents to the shorter acyl chains in CL in acb1 mutants. Based on the findings, we conclude that the fatty acid composition of mature CL in yeast is governed by the substrate specificity of the CL-specific lipase Cld1p and the fatty acid composition of the Taz1p substrates. PMID:19656950

  9. Development and modification of glass membranes for aggressive gas separations

    Energy Technology Data Exchange (ETDEWEB)

    Lindbraaten, Arne

    2004-07-01

    Chlorine as a chemical is widespread in industry and found in a great variety of processes ranging from water purification to plastic production. In this thesis, a magnesium production factory was chosen as an example because it involved both chlorine - air separation and hydrogen -hydrogen chloride separation. Previously, various types of membrane materials have been tested out for their applicability in the chosen process. The materials previously tested either lacked sufficient membrane performance or sufficient membrane stability. As an attempt to improve both the membrane performance and stability, glass membranes are used in this thesis. Glass membranes are prepared from a borosilicate glass, via a phase separation followed by an acid leaching route. By choosing the appropriate phase separation temperature and acid to glass ratio, the membrane can be produced with an average pore diameter of 2 nm (or 4 nm). However, the 2 nm average pore size is still too large to separate gases with separation selectivities beyond the selectivities predicted from Knudsen diffusion theory. If the pores are narrowed, the selectivity may be raised while the flux hopefully is maintained. The narrowing of the pores was done by a silane coupling to the surface OH-groups on the glass. The silane coupling agent is of the dimethyl-acyl-chlorosilane type, where the length of the acyl chain varies from 1 carbon up to 18 carbons. Glass fibres are also tested in this work, which are produced without phase separation and their average pore size is smaller than the surface-modified glasses. To be able to compare the performance of the various membranes, performance measurements are performed and these measurements are evaluated by the separation power (product of the selectivity and the permeability of the fastest permeating compound). Because of the harsh chlorine or hydrogen chloride environment, to which the membranes are exposed in this work, the membrane stability is at least as

  10. N-Acyl amino acids and N-acyl neurotransmitter conjugates: neuromodulators and probes for new drug targets

    OpenAIRE

    Connor, Mark; Vaughan, Chris W; Vandenberg, Robert J.

    2010-01-01

    The myriad functions of lipids as signalling molecules is one of the most interesting fields in contemporary pharmacology, with a host of compounds recognized as mediators of communication within and between cells. The N-acyl conjugates of amino acids and neurotransmitters (NAANs) have recently come to prominence because of their potential roles in the nervous system, vasculature and the immune system. NAAN are compounds such as glycine, GABA or dopamine conjugated with long chain fatty acids...

  11. Novel cinchona carbamate selectors with complementary enantioseparation characteristics for N-acylated amino acids.

    Science.gov (United States)

    Krawinkler, Karl Heinz; Maier, Norbert M; Ungaro, Rocco; Sansone, Francesco; Casnati, Alessandro; Lindner, Wolfgang

    2003-01-01

    The synthesis and chromatographic evaluation of the enantiomer separation capabilities of covalently immobilized calix[4]arene-cinchona carbamate hybrid type receptors derived from quinine (QN) and its corresponding C9-epimer (eQN) in different solvents are reported. The receptors display complementary enantiomer separation profiles in terms of elution order, chiral substrate specificity, and mobile phase characteristics, indicating the existence of two distinct chiral recognition mechanisms. The QN-derived receptor binds the (S)-enantiomers of N-acylated amino acids more strongly, shows preferential recognition of open-chained amino acids, and superior enantioselectivity in polar media such as methanol/acetic acid. In contrast, the eQN congener preferentially recognizes the corresponding (R)-enantiomers, displays good enantioselectivity (alpha up to 1.74) for cyclic amino acids, and enhanced stereodiscriminating properties in apolar mobile phases, e.g., chloroform/acetic acid. A comparison of the enantiomer separation profiles with those of the corresponding QN and eQN tert-butyl carbamate congeners indicates no significant level of cooperativity between the calix[4]arene module and the cinchona units in terms of overall chiral recognition, most probably as a consequence of residual conformational flexibility of the calixarene module and the carbamate linkage.

  12. Chemoselective O-acylation of hydroxyamino acids and amino alcohols under acidic reaction conditions: History, scope and applications

    Directory of Open Access Journals (Sweden)

    Tor E. Kristensen

    2015-04-01

    Full Text Available Amino acids, whether natural, semisynthetic or synthetic, are among the most important and useful chiral building blocks available for organic chemical synthesis. In principle, they can function as inexpensive, chiral and densely functionalized starting materials. On the other hand, the use of amino acid starting materials routinely necessitates protective group chemistry, and in reality, large-scale preparations of even the simplest side-chain derivatives of many amino acids often become annoyingly strenuous due to the necessity of employing protecting groups, on one or more of the amino acid functionalities, during the synthetic sequence. However, in the case of hydroxyamino acids such as hydroxyproline, serine, threonine, tyrosine and 3,4-dihydroxyphenylalanine (DOPA, many O-acyl side-chain derivatives are directly accessible via a particularly expedient and scalable method not commonly applied until recently. Direct acylation of unprotected hydroxyamino acids with acyl halides or carboxylic anhydrides under appropriately acidic reaction conditions renders possible chemoselective O-acylation, furnishing the corresponding side-chain esters directly, on multigram-scale, in a single step, and without chromatographic purification. Assuming a certain degree of stability under acidic reaction conditions, the method is also applicable for a number of related compounds, such as various amino alcohols and the thiol-functional amino acid cysteine. While the basic methodology underlying this approach has been known for decades, it has evolved through recent developments connected to amino acid-derived chiral organocatalysts to become a more widely recognized procedure for large-scale preparation of many useful side-chain derivatives of hydroxyamino acids and related compounds. Such derivatives are useful in peptide chemistry and drug development, as amino acid amphiphiles for asymmetric catalysis, and as amino acid acrylic precursors for preparation of

  13. A polymorphic variant in the human electron transfer flavoprotein alpha-chain (alpha-T171) displays decreased thermal stability and is overrepresented in very-long-chain acyl-CoA dehydrogenase-deficient patients with mild childhood presentation

    DEFF Research Database (Denmark)

    Bross, P; Pedersen, P; Nyholm, M;

    1999-01-01

    , whereas the two variants of the beta-M/T154 polymorphism did not differ. We wished to test the hypothesis that these polymorphisms might constitute susceptibility factors and therefore determined their allele and genotype frequencies in (i) control individuals, (ii) medium-chain acyl-CoA dehydrogenase......-deficient patients homozygous for the K304E mutation (MCAD E304), (iii) a group of patients with elevated urinary excretion of ethylmalonic acid (EMA) possibly due to decreased short-chain acyl-CoA dehydrogenase activity, and (iv) in patients with proven deficiency of very-long-chain acyl-CoA dehydrogenase (VLCAD......). No significant overrepresentations or underrepresentations were found in the first two patient groups, suggesting that the polymorphisms studied are not significant susceptibility factors in either the MCAD E304 or the EMA patient group. However, in the VLCAD deficient patients the alpha-T171 variant (decreased...

  14. Production of structured lipids: acyl migration during enzymatic interesterification and downstream processing

    DEFF Research Database (Denmark)

    Xu, Xuebing

    1997-01-01

    -2 position or sn-1,3 positions of glycerol backbone. These kinds of lipids are reported to be promising for both enteral and parenteral nutrition. However, acyl migration occurs in the reaction stage and downstream purification process. This side-reaction causes by-products which are harmful to the...... required products. In this paper, the reasons of acyl migration and factors affecting the acyl migration were reviewed and discussed. The possible solutions were also evaluated....

  15. Synthesis of a stationary phase based on silica modified with branched octadecyl groups by Michael addition and photoinduced thiol-yne click chemistry for the separation of basic compounds.

    Science.gov (United States)

    Huang, Guang; Ou, Junjie; Wang, Hongwei; Ji, Yongsheng; Wan, Hao; Zhang, Zhang; Peng, Xiaojun; Zou, Hanfa

    2016-04-01

    A novel silica-based stationary phase with branched octadecyl groups was prepared by the sequential employment of the Michael addition reaction and photoinduced thiol-yne click chemistry with 3-aminopropyl-functionalized silica microspheres as the initial material. The resulting stationary phase denoted as SiO2 -N(C18)4 was characterized by elemental analysis, FTIR spectroscopy and Raman spectroscopy, demonstrating the existence of branched octadecyl groups in silica microspheres. The separations of benzene homologous compounds, acid compounds and amine analogues were conducted, demonstrating mixed-mode separation mechanism on SiO2 -N(C18)4 . Baseline separation of basic drugs mixture was acquired with the mobile phase of acetonitrile/H2 O (5%, v/v). SiO2 -N(C18)4 was further applied to separate Corydalis yanhusuo Wang water extracts, and more baseline separation peaks were obtained for SiO2 -N(C18)4 than those on Atlantis dC18 column. It can be expected that this new silica-based stationary phase will exhibit great potential in the analysis of basic compounds. PMID:26910263

  16. A high-performance liquid chromatography-based radiometric assay for acyl-CoA:alcohol transacylase from jojoba.

    Science.gov (United States)

    Garver, W S; Kemp, J D; Kuehn, G D

    1992-12-01

    Acyl-CoA:alcohol transacylase catalyzes the final step in the biosynthesis of storage liquid wax esters from acyl-CoA fatty acids and fatty alcohols in a limited number of microbes, algae, and Simmondsia chinensis Link (jojoba). An improved and automated method of enzyme assay for this catalyst from cotyledons of jojoba is described. The assay method uses reversed-phase C18 high performance liquid chromatography (HPLC) to separate the labeled C30:1 liquid wax product, [14C]-dodecanyl-octadecenoate, from the unreacted substrate, [14C]octadecenoyl-CoA (oleyl-CoA), and other components produced from enzymes present in the crude homogenate of jojoba cotyledons, including [14C]-octadecenoic acid (oleic acid) and [14C]octadecenol (oleyol). Methods are also described for microscale chemical synthesis in one vessel of 14C-radiolabeled substrates and products for the transacylase. These labeled reagents are required to confirm the HPLC separations of reaction products. The radioactive components are quantitated using an on-line flow-through scintillation detector enabling sensitive and precise analysis of the reaction products.

  17. Ultracapacitor separator

    Science.gov (United States)

    Wei, Chang; Jerabek, Elihu Calvin; LeBlanc, Jr., Oliver Harris

    2001-03-06

    An ultracapacitor includes two solid, nonporous current collectors, two porous electrodes separating the collectors, a porous separator between the electrodes and an electrolyte occupying the pores in the electrodes and separator. The electrolyte is a polar aprotic organic solvent and a salt. The porous separator comprises a wet laid cellulosic material.

  18. Cardiolipin Molecular Species with Shorter Acyl Chains Accumulate in Saccharomyces cerevisiae Mutants Lacking the Acyl Coenzyme A-binding Protein Acb1p

    Science.gov (United States)

    Rijken, Pieter J.; Houtkooper, Riekelt H.; Akbari, Hana; Brouwers, Jos F.; Koorengevel, Martijn C.; de Kruijff, Ben; Frentzen, Margrit; Vaz, Frédéric M.; de Kroon, Anton I. P. M.

    2009-01-01

    The function of the mitochondrial phospholipid cardiolipin (CL) is thought to depend on its acyl chain composition. The present study aims at a better understanding of the way the CL species profile is established in Saccharomyces cerevisiae by using depletion of the acyl-CoA-binding protein Acb1p as a tool to modulate the cellular acyl chain content. Despite the presence of an intact CL remodeling system, acyl chains shorter than 16 carbon atoms (C16) were found to accumulate in CL in cells lacking Acb1p. Further experiments revealed that Taz1p, a key CL remodeling enzyme, was not responsible for the shortening of CL in the absence of Acb1p. This left de novo CL synthesis as the only possible source of acyl chains shorter than C16 in CL. Experiments in which the substrate specificity of the yeast cardiolipin synthase Crd1p and the acyl chain composition of individual short CL species were investigated, indicated that both CL precursors (i.e. phosphatidylglycerol and CDP-diacylglycerol) contribute to comparable extents to the shorter acyl chains in CL in acb1 mutants. Based on the findings, we conclude that the fatty acid composition of mature CL in yeast is governed by the substrate specificity of the CL-specific lipase Cld1p and the fatty acid composition of the Taz1p substrates. PMID:19656950

  19. Supramolecular arrangement in mono and bi-camphor acyl hydrazones: A structural study

    Science.gov (United States)

    Galvão, Adelino M.; Carvalho, M. Fernanda N. N.; Ferreira, Ana S. D.

    2016-03-01

    New acyl hydrazones were synthesized by condensation with camphorquinone aiming at extending the range of applications of the biologically active camphor compounds and structural studies by XRD, 1H-NMR and IR were used in conjunction with advanced computational methodologies to understand the new structural chemistry enabled by the conjugation of the camphor ketone group to the hydrazone Ndbnd C double bond. In particular, were analysed supramolecular arrangements either by hydrogen bonding to water molecules or electrostatic interactions with non protic solvents. The relative stability of all conformers (E/Z) prompted by the hydrazone bond was addressed by state of the art methods such as CR-CCSD(T) and their inter-conversion in both S0 and S1 by CR-EOM-CCSD(T).

  20. A multisubstrate assay for lipases/esterases: assessing acyl chain length selectivity by reverse-phase high-performance liquid chromatography.

    Science.gov (United States)

    Divakar, K; Gautam, Pennathur

    2014-03-01

    Lipases and esterases are hydrolytic enzymes and are known to hydrolyze esters with unique substrate specificity and acyl chain length selectivity. We have developed a simple competitive multiple substrate assay for determination of acyl chain length selectivity of lipases/esterases using RP-HPLC with UV detection. A method for separation and quantification of 4-nitrophenyl fatty acid esters (C4-C18) was developed and validated. The chain length selectivity of five lipases and two esterases was determined in a multisubstrate reaction system containing equimolar concentrations of 4-nitrophenyl esters (C4-C18). This assay is simple, reproducible, and a useful tool for determining chain length selectivity of lipases/esterases. PMID:24316114

  1. Small-molecule inhibitor binding to an N-acyl-homoserine lactone synthase.

    Science.gov (United States)

    Chung, Jiwoung; Goo, Eunhye; Yu, Sangheon; Choi, Okhee; Lee, Jeehyun; Kim, Jinwoo; Kim, Hongsup; Igarashi, Jun; Suga, Hiroaki; Moon, Jae Sun; Hwang, Ingyu; Rhee, Sangkee

    2011-07-19

    Quorum sensing (QS) controls certain behaviors of bacteria in response to population density. In gram-negative bacteria, QS is often mediated by N-acyl-L-homoserine lactones (acyl-HSLs). Because QS influences the virulence of many pathogenic bacteria, synthetic inhibitors of acyl-HSL synthases might be useful therapeutically for controlling pathogens. However, rational design of a potent QS antagonist has been thwarted by the lack of information concerning the binding interactions between acyl-HSL synthases and their ligands. In the gram-negative bacterium Burkholderia glumae, QS controls virulence, motility, and protein secretion and is mediated by the binding of N-octanoyl-L-HSL (C8-HSL) to its cognate receptor, TofR. C8-HSL is synthesized by the acyl-HSL synthase TofI. In this study, we characterized two previously unknown QS inhibitors identified in a focused library of acyl-HSL analogs. Our functional and X-ray crystal structure analyses show that the first inhibitor, J8-C8, binds to TofI, occupying the binding site for the acyl chain of the TofI cognate substrate, acylated acyl-carrier protein. Moreover, the reaction byproduct, 5'-methylthioadenosine, independently binds to the binding site for a second substrate, S-adenosyl-L-methionine. Closer inspection of the mode of J8-C8 binding to TofI provides a likely molecular basis for the various substrate specificities of acyl-HSL synthases. The second inhibitor, E9C-3oxoC6, competitively inhibits C8-HSL binding to TofR. Our analysis of the binding of an inhibitor and a reaction byproduct to an acyl-HSL synthase may facilitate the design of a new class of QS-inhibiting therapeutic agents.

  2. Imaging N-acyl homoserine lactone quorum sensing in vivo

    DEFF Research Database (Denmark)

    Christensen, Louise Dahl; van Gennip, Maria; Jakobsen, Tim Holm;

    2011-01-01

    In order to study N-acyl homoserine lactone (AHL)-based quorum sensing in vivo, we present a protocol using an Escherichia coli strain equipped with a luxR-based monitor system, which in the presence of exogenous AHL molecules expresses a green fluorescent protein (GFP). Lungs from mice challenged...... intratracheally with alginate beads containing both a P. aeruginosa strain together with the E. coli monitor strain can be investigated at different time points postinfection. Epifluorescent or confocal scanning laser microscopy (CSLM) is used to detect the GFP-expressing E. coli monitor strain in the lung...

  3. Acyl-CoA binding proteins; structural and functional conservation over 2000 MYA

    DEFF Research Database (Denmark)

    Faergeman, Nils J; Wadum, Majken; Feddersen, Søren;

    2007-01-01

    -CoA binding protein, ACBP, has been proposed to play a pivotal role in the intracellular trafficking and utilization of long-chain fatty acyl-CoA esters. Depletion of acyl-CoA binding protein in yeast results in aberrant organelle morphology incl. fragmented vacuoles, multi-layered plasma membranes...

  4. A simple, effective, green method for regioselective 3-acylation of unprotected indoles

    DEFF Research Database (Denmark)

    Tran, Phuong Huong; Tran, Hai N.; Hansen, Poul Erik;

    2015-01-01

    A fast and green method is developed for regioselective acylation of indoles in the 3-position without the need for protection of the NH position. The method is based on Friedel-Crafts acylation using acid anhydrides. The method has been optimized, and Y(OTf)3 in catalytic amounts is found...

  5. Influence of Lipid A Acylation Pattern on Membrane Permeability and Innate Immune Stimulation

    Directory of Open Access Journals (Sweden)

    Robert K. Ernst

    2013-08-01

    Full Text Available Lipid A, the hydrophobic anchor of lipopolysaccharide (LPS, is an essential component in the outer membrane of Gram-negative bacteria. It can stimulate the innate immune system via Toll-like receptor 4/myeloid differentiation factor 2 (TLR4/MD2, leading to the release of inflammatory cytokines. In this study, six Escherichia coli strains which can produce lipid A with different acylation patterns were constructed; the influence of lipid A acylation pattern on the membrane permeability and innate immune stimulation has been systematically investigated. The lipid A species were isolated and identified by matrix assisted laser ionization desorption-time of flight/tandem mass spectrometry. N-Phenyl naphthylamine uptake assay and antibiotic susceptibility test showed that membrane permeability of these strains were different. The lower the number of acyl chains in lipid A, the stronger the membrane permeability. LPS purified from these strains were used to stimulate human or mouse macrophage cells, and different levels of cytokines were induced. Compared with wild type hexa-acylated LPS, penta-acylated, tetra-acylated and tri-acylated LPS induced lower levels of cytokines. These results suggest that the lipid A acylation pattern influences both the bacterial membrane permeability and innate immune stimulation. The results would be useful for redesigning the bacterial membrane structure and for developing lipid A vaccine adjuvant.

  6. Suppression of acyl migration in enzymatic production of structured lipids through temperature programming

    DEFF Research Database (Denmark)

    Yang, Tiankui; Fruekilde, Maj-Britt; Xu, Xuebing

    2005-01-01

    the feasibility of suppressing acyl migration by a programmed change of reaction temperature without loss of reaction yield. The model reactions were the acidolysis of tripalmitin with conjugated linoleic acid (CLA) or with caprylic acid (CA) targeted for human milk fat substitutes. Acyl migration...

  7. Nitrite-Oxidizing Bacterium Nitrobacter winogradskyi Produces N-Acyl-Homoserine Lactone Autoinducers.

    Science.gov (United States)

    Mellbye, Brett L; Bottomley, Peter J; Sayavedra-Soto, Luis A

    2015-09-01

    Nitrobacter winogradskyi is a chemolithotrophic bacterium that plays a role in the nitrogen cycle by oxidizing nitrite to nitrate. Here, we demonstrate a functional N-acyl-homoserine lactone (acyl-HSL) synthase in this bacterium. The N. winogradskyi genome contains genes encoding a putative acyl-HSL autoinducer synthase (nwi0626, nwiI) and a putative acyl-HSL autoinducer receptor (nwi0627, nwiR) with amino acid sequences 38 to 78% identical to those in Rhodopseudomonas palustris and other Rhizobiales. Expression of nwiI and nwiR correlated with acyl-HSL production during culture. N. winogradskyi produces two distinct acyl-HSLs, N-decanoyl-l-homoserine lactone (C10-HSL) and a monounsaturated acyl-HSL (C10:1-HSL), in a cell-density- and growth phase-dependent manner, during batch and chemostat culture. The acyl-HSLs were detected by bioassay and identified by ultraperformance liquid chromatography with information-dependent acquisition mass spectrometry (UPLC-IDA-MS). The C=C bond in C10:1-HSL was confirmed by conversion into bromohydrin and detection by UPLC-IDA-MS.

  8. Acylation of aromatic alcohols and phenols over InCl3/montmorillonite K-10 catalysts

    Indian Academy of Sciences (India)

    Vasant R Choudhary; Kailash Y Patil; Suman K Jana

    2004-03-01

    Montmorillonite K-10 clay supported InCl3 is a highly active catalyst for the acylation of aromatic alcohols and phenols with different acyl chlorides. This catalyst can be reused in reactions a number of times without very significant loss of catalytic activity.

  9. Synthesis of photoactivatable azido-acyl caged oxazine fluorophores for live-cell imaging.

    Science.gov (United States)

    Anzalone, Andrew V; Chen, Zhixing; Cornish, Virginia W

    2016-07-19

    We report the design and synthesis of a photoactivatable azido-acyl oxazine fluorophore. Photoactivation is achieved cleanly and rapidly with UV light, producing a single fluorescent oxazine photoproduct. We demonstrate the utility of azido-acyl caged oxazines for protein specific labeling in living mammalian cells using the TMP-tag technology. PMID:27377037

  10. Acylation of salmon calcitonin modulates in vitro intestinal peptide flux through membrane permeability enhancement

    DEFF Research Database (Denmark)

    Trier, Sofie; Linderoth, Lars; Bjerregaard, Simon;

    2015-01-01

    Acylation of peptide drugs with fatty acid chains has proven beneficial for prolonging systemic circulation, as well as increasing enzymatic stability and interactions with lipid cell membranes. Thus, acylation offers several potential benefits for oral delivery of therapeutic peptides, and we hy...

  11. Separation and Identification of a Mixture of Group 6 Transition-Metal Carbonyl Compounds Using GC-MS in the General Chemistry Curriculum

    Science.gov (United States)

    Fong, Lawrence K.

    2004-01-01

    Students in the general chemistry course are advised to scrutinize data obtained by gas chromatograph (GC) for segregation, and mass spectroscopy (MS) for recognizing combination of group 6 transition-metal carbonyl compounds. The GC-MS method arouses students' interest, as it can be applied to real-world situations, such as the routine…

  12. 40 CFR 721.7270 - 1-propanaminium, 3-amino-, N,N,N-trimethyl-N-soya acyl derivs., chloride.

    Science.gov (United States)

    2010-07-01

    ...-trimethyl-N-soya acyl derivs., chloride. 721.7270 Section 721.7270 Protection of Environment ENVIRONMENTAL...-soya acyl derivs., chloride. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as 1-propanaminium, 3-amino-, N,N,N-trimethyl-N-soya acyl...

  13. 40 CFR 721.10056 - Benzenemethanaminium, N-(3-aminopropyl)-N,N-dimethyl-, N-soya acyl derivs., chlorides.

    Science.gov (United States)

    2010-07-01

    ...)-N,N-dimethyl-, N-soya acyl derivs., chlorides. 721.10056 Section 721.10056 Protection of Environment...-aminopropyl)-N,N-dimethyl-, N-soya acyl derivs., chlorides. (a) Chemical substance and significant new uses...-dimethyl-, N-soya acyl derivs., chlorides (PMN P-03-47; CAS No. 90194-13-1) is subject to reporting...

  14. Relationships between acylated ghrelin with growth hormone, insulin resistance, lipid profile, and cardio respiratory function in lean and obese men

    Directory of Open Access Journals (Sweden)

    Hasan Matin Homaee

    2011-01-01

    Conclusions: Obese and lean inactive young men had different levels of acylated ghrelin, GH, insulin, insulin resistance index, cardiorespiratory function and body fat percent. Body fat percent, insulin, and GH levels appear to be best determinant factors of acylated ghrelin levels. Also, in both obese and lean young men, higher levels of cardiovascular function were associated with higher levels of acylated ghrelin.

  15. Role of long-chain fatty acyl-CoA esters in the regulation of metabolism and in cell signalling

    DEFF Research Database (Denmark)

    Færgeman, Nils J.; Knudsen, J

    1997-01-01

    The intracellular concentration of free unbound acyl-CoA esters is tightly controlled by feedback inhibition of the acyl-CoA synthetase and is buffered by specific acyl-CoA binding proteins. Excessive increases in the concentration are expected to be prevented by conversion into acylcarnitines or...

  16. In vivo MRS assessment of altered fatty acyl unsaturation in liver tumor formation of a TGFα/c-myc transgenic mouse model*

    OpenAIRE

    Griffitts, J.; Tesiram, Y.; Reid, G. E.; Saunders, D; Floyd, R A; Towner, R. A.

    2009-01-01

    Current detection methods (computed tomography, ultrasound, and MRI) for hepatocarcinogenesis in humans rely on visual confirmation of neoplastic formations. A more effective early detection method is needed. Using in vivo magnetic resonance spectroscopy (MRS), we show that alterations in the integral ratios of the bis-allyl to vinyl hydrogen protons in unsaturated lipid fatty acyl groups correlate with the development of neoplastic formations in vivo in a TGFα/c-myc mouse hepatocellular carc...

  17. Central acylated ghrelin improves memory function and hippocampal AMPK activation and partly reverses the impairment of energy and glucose metabolism in rats infused with β-amyloid.

    Science.gov (United States)

    Kang, Suna; Moon, Na Rang; Kim, Da Sol; Kim, Sung Hoon; Park, Sunmin

    2015-09-01

    Ghrelin is a gastric hormone released during the fasting state that targets the hypothalamus where it induces hunger; however, emerging evidence suggests it may also affect memory function. We examined the effect of central acylated-ghrelin and DES-acetylated ghrelin (native ghrelin) on memory function and glucose metabolism in an experimentally induced Alzheimer's disease (AD) rat model. AD rats were divided into 3 groups and Non-AD rats were used as a normal-control group. Each rat in the AD groups had intracerebroventricular (ICV) infusion of β-amyloid (25-35; 16.8nmol/day) into the lateral ventricle for 3 days, and then the pumps were changed to infuse either acylated-ghrelin (0.2nmol/h; AD-G), DES-acylated ghrelin (0.2nmol/h; AD-DES-G), or saline (control; AD-C) for 3 weeks. The Non-AD group had ICV infusion of β-amyloid (35-25) which does not deposit in the hippocampus. During the next 3 weeks memory function, food intake, body weight gain, body fat composition, and glucose metabolism were measured. AD-C exhibited greater β-amyloid deposition compared to Non-AD-C, and AD-G suppressed the increased β-amyloid deposition and potentiated the phosphorylation AMPK. In addition, AD-G increased the phosphorylation GSK and decreased the phosphorylation of Tau in comparison to AD-C and AD-DES-G. Cognitive function, measured by passive avoidance and water maze tests, was much lower in AD-C than Non-AD-C whereas AD-G but not AD-DES-G prevented the decrease (pintermittent fasting to facilitate sustained elevations of acyl-ghrelin should be investigated for cognitive and metabolic benefits, especially in person with early symptoms of memory impairment. PMID:26188171

  18. Bioorthogonal mimetics of palmitoyl-CoA and myristoyl-CoA and their subsequent isolation by click chemistry and characterization by mass spectrometry reveal novel acylated host-proteins modified by HIV-1 infection.

    Science.gov (United States)

    Colquhoun, David R; Lyashkov, Alexey E; Ubaida Mohien, Ceereena; Aquino, Veronica N; Bullock, Brandon T; Dinglasan, Rhoel R; Agnew, Brian J; Graham, David R M

    2015-06-01

    Protein acylation plays a critical role in protein localization and function. Acylation is essential for human immunodeficiency virus 1 (HIV-1) assembly and budding of HIV-1 from the plasma membrane in lipid raft microdomains and is mediated by myristoylation of the Gag polyprotein and the copackaging of the envelope protein is facilitated by colocalization mediated by palmitoylation. Since the viral accessory protein NEF has been shown to alter the substrate specificity of myristoyl transferases, and alter cargo trafficking lipid rafts, we hypothesized that HIV-1 infection may alter protein acylation globally. To test this hypothesis, we labeled HIV-1 infected cells with biomimetics of acyl azides, which are incorporated in a manner analogous to natural acyl-Co-A. A terminal azide group allowed us to use a copper catalyzed click chemistry to conjugate the incorporated modifications to a number of substrates to carry out SDS-PAGE, fluorescence microscopy, and enrichment for LC-MS/MS. Using LC-MS/MS, we identified 103 and 174 proteins from the myristic and palmitic azide enrichments, with 27 and 45 proteins respectively that differentiated HIV-1 infected from uninfected cells. This approach has provided us with important insights into HIV-1 biology and is widely applicable to many virological systems.

  19. Heteropoly acid encapsulated into zeolite imidazolate framework (ZIF-67) cage as an efficient heterogeneous catalyst for Friedel-Crafts acylation

    Science.gov (United States)

    Ammar, Muhammad; Jiang, Sai; Ji, Shengfu

    2016-01-01

    A new strategy has been developed for the encapsulation of the phosphotungstic heteropoly acid (H3PW12O40 denoted as PTA) into zeolite imidazolate framework (ZIF-67) cage and the PTA@ZIF-67(ec) catalysts with different PTA content were prepared. The structure of the catalysts was characterized by XRD, BET, SEM, FT-IR, ICP-AES and TG. The catalytic activity and recovery properties of the catalysts for the Friedel-Crafts acylation of anisole with benzoyl chloride were evaluated. The results showed that 14.6-31.7 wt% PTA were encapsulated in the ZIF-67 cage. The PTA@ZIF-67(ec) catalysts had good catalytic activity for Friedel-Crafts acylation. The conversion of anisole can reach ~100% and the selectivity of the production can reach ~94% over 26.5 wt% PTA@ZIF-67(ec) catalyst under the reaction condition of 120 °C and 6 h. After reaction, the catalyst can be easily separated from the reaction mixture by the centrifugation. The recovered catalyst can be reused five times and the selectivity can be kept over 90%.

  20. Liquid-liquid extraction and separation of VIII group elements, especially ruthenium, by synergic combinations or aromatic polyimines and micellar cationic exchangers

    International Nuclear Information System (INIS)

    This thesis aims to characterize and to quantify the chemical equilibria involved in d-elements liquid-liquid extraction systems, especially elements belonging to the VIII group (Fe, Ni, Co, Ru, Rh, Pd, Pt). These systems are composed of synergic combination of aromatic polyimines and micellar cationic exchangers. Substitutions are first performed in aqueous acidic media by aromatic polyimines; then extractions are operated using micellic canionic exchangers. Chemical equilibria, selectivity effects, especially those due to ion-pair formations, kinetics, extractant behaviour are analysed and quantified

  1. Structure-activity relationship studies on acremomannolipin A, the potent calcium signal modulator with a novel glycolipid structure 4: Role of acyl side chains on d-mannose.

    Science.gov (United States)

    Tsutsui, Nozomi; Tanabe, Genzoh; Ikeda, Nami; Okamura, Saika; Ogawa, Marika; Miyazaki, Kuniko; Kita, Ayako; Sugiura, Reiko; Muraoka, Osamu

    2016-10-01

    As part of an ongoing study on the structure-activity relationship of acremomannolipin A (1)-the novel glycolipid isolated from Acremonium strictum possessing potent calcium signal-modulating activity-the role of acyl substituents on the d-mannose moiety was examined. Three partially deacylated homologs (2a-2c) and 20 homologs (2d-2w) bearing different acyloxy side chains were synthesized via the stereoselective β-mannosylation of appropriately protected mannosyl sulfoxides (3) with d-mannitol derivatives (4), and their calcium signal-modulating activities were examined. The activities of 2a-2c were completely lost. Homologs bearing relatively short acyloxy groups at C-3, C-4, and C-6 positions (2t-2v) exhibited less activity than 1, whereas a heptanoyl homolog (2w: C7) maintained activity nearly equal to that of 1. When the acyl groups at these three positions were substituted by an octanoyl group (2i: C8), the activity was completely lost. On the other hand, of the 10 homologs in which the octanoyl at C-2 was substituted by other acyloxy moieties (2j-2s), three (2m: C7, 2n: C9, 2o: C10) maintained potent activity. These results suggested that peracylated mannose structure is critical for calcium signal-modulating activity, and this activity is precisely dependent on the length of four acyl side chains on d-mannose. PMID:27243802

  2. Photoaffinity Labeling of Developing Jojoba Seed Microsomal Membranes with a Photoreactive Analog of Acyl-Coenzyme A (Acyl-CoA) (Identification of a Putative Acyl-CoA:Fatty Alcohol Acyltransferase.

    Science.gov (United States)

    Shockey, J. M.; Rajasekharan, R.; Kemp, J. D.

    1995-01-01

    Jojoba (Simmondsia chinensis, Link) is the only plant known that synthesizes liquid wax. The final step in liquid wax biosynthesis is catalyzed by an integral membrane enzyme, fatty acyl-coenzyme A (CoA):fatty alcohol acyltransferase, which transfers an acyl chain from acyl-CoA to a fatty alcohol to form the wax ester. To purify the acyltransferase, we have labeled the enzyme with a radioiodinated, photoreactive analog of acyl-CoA, 12-[N-(4-azidosalicyl)amino] dodecanoyl-CoA (ASD-CoA). This molecule acts as an inhibitor of acyltransferase activity in the dark and as an irreversible inhibitor upon exposure to ultraviolet light. Oleoyl-CoA protects enzymatic activity in a concentration-dependent manner. Photolysis of microsomal membranes with labeled ASD-CoA resulted in strong labeling of two polypeptides of 57 and 52 kD. Increasing concentrations of oleoyl-CoA reduced the labeling of the 57-kD polypeptide dramatically, whereas the labeling of the 52-kD polypeptide was much less responsive to oleoyl-CoA. Also, unlike the other polypeptide, the labeling of the 57-kD polypeptide was enhanced considerably when photolyzed in the presence of dodecanol. These results suggest that a 57-kD polypeptide from jojoba microsomes may be the acyl-CoA:fatty alcohol acyltransferase.

  3. Toxicity of Carboxylic Acid-Containing Drugs: The Role of Acyl Migration and CoA Conjugation Investigated.

    Science.gov (United States)

    Lassila, Toni; Hokkanen, Juho; Aatsinki, Sanna-Mari; Mattila, Sampo; Turpeinen, Miia; Tolonen, Ari

    2015-12-21

    Many carboxylic acid-containing drugs are associated with idiosyncratic drug toxicity (IDT), which may be caused by reactive acyl glucuronide metabolites. The rate of acyl migration has been earlier suggested as a predictor of acyl glucuronide reactivity. Additionally, acyl Coenzyme A (CoA) conjugates are known to be reactive. Here, 13 drugs with a carboxylic acid moiety were incubated with human liver microsomes to produce acyl glucuronide conjugates for the determination of acyl glucuronide half-lives by acyl migration and with HepaRG cells to monitor the formation of acyl CoA conjugates, their further conjugate metabolites, and trans-acylation products with glutathione. Additionally, in vitro cytotoxicity and mitochondrial toxicity experiments were performed with HepaRG cells to compare the predictability of toxicity. Clearly, longer acyl glucuronide half-lives were observed for safe drugs compared to drugs that can cause IDT. Correlation between half-lives and toxicity classification increased when "relative half-lives," taking into account the formation of isomeric AG-forms due to acyl migration and eliminating the effect of hydrolysis, were used instead of plain disappearance of the initial 1-O-β-AG-form. Correlation was improved further when a daily dose of the drug was taken into account. CoA and related conjugates were detected primarily for the drugs that have the capability to cause IDT, although some exceptions to this were observed. Cytotoxicity and mitochondrial toxicity did not correlate to drug safety. On the basis of the results, the short relative half-life of the acyl glucuronide (high acyl migration rate), high daily dose and detection of acyl CoA conjugates, or further metabolites derived from acyl CoA together seem to indicate that carboxylic acid-containing drugs have a higher probability to cause drug-induced liver injury (DILI). PMID:26558897

  4. Evolutionary view of acyl-CoA diacylglycerol acyltransferase (DGAT, a key enzyme in neutral lipid biosynthesis

    Directory of Open Access Journals (Sweden)

    Margis-Pinheiro Marcia

    2011-09-01

    Full Text Available Abstract Background Triacylglycerides (TAGs are a class of neutral lipids that represent the most important storage form of energy for eukaryotic cells. DGAT (acyl-CoA: diacylglycerol acyltransferase; EC 2.3.1.20 is a transmembrane enzyme that acts in the final and committed step of TAG synthesis, and it has been proposed to be the rate-limiting enzyme in plant storage lipid accumulation. In fact, two different enzymes identified in several eukaryotic species, DGAT1 and DGAT2, are the main enzymes responsible for TAG synthesis. These enzymes do not share high DNA or protein sequence similarities, and it has been suggested that they play non-redundant roles in different tissues and in some species in TAG synthesis. Despite a number of previous studies on the DGAT1 and DGAT2 genes, which have emphasized their importance as potential obesity treatment targets to increase triacylglycerol accumulation, little is known about their evolutionary timeline in eukaryotes. The goal of this study was to examine the evolutionary relationship of the DGAT1 and DGAT2 genes across eukaryotic organisms in order to infer their origin. Results We have conducted a broad survey of fully sequenced genomes, including representatives of Amoebozoa, yeasts, fungi, algae, musses, plants, vertebrate and invertebrate species, for the presence of DGAT1 and DGAT2 gene homologs. We found that the DGAT1 and DGAT2 genes are nearly ubiquitous in eukaryotes and are readily identifiable in all the major eukaryotic groups and genomes examined. Phylogenetic analyses of the DGAT1 and DGAT2 amino acid sequences revealed evolutionary partitioning of the DGAT protein family into two major DGAT1 and DGAT2 clades. Protein secondary structure and hydrophobic-transmembrane analysis also showed differences between these enzymes. The analysis also revealed that the MGAT2 and AWAT genes may have arisen from DGAT2 duplication events. Conclusions In this study, we identified several DGAT1 and DGAT2

  5. Acyl-CoA synthetase activity links wild-type but not mutant a-Synuclein to brain arachidonate metabolism

    DEFF Research Database (Denmark)

    Golovko, Mikhail; Rosenberger, Thad; Færgeman, Nils J.;

    2006-01-01

    Because alpha-synuclein (Snca) has a role in brain lipid metabolism, we determined the impact that the loss of alpha-synuclein had on brain arachidonic acid (20:4n-6) metabolism in vivo using Snca-/- mice. We measured [1-(14)C]20:4n-6 incorporation and turnover kinetics in brain phospholipids using...... an established steady-state kinetic model. Liver was used as a negative control, and no changes were observed between groups. In Snca-/- brains, there was a marked reduction in 20:4n-6-CoA mass and in microsomal acyl-CoA synthetase (Acsl) activity toward 20:4n-6. Microsomal Acsl activity was completely restored...... after the addition of exogenous wild-type mouse or human alpha-synuclein, but not by A30P, E46K, and A53T forms of alpha-synuclein. Acsl and acyl-CoA hydrolase expression was not different between groups. The incorporation and turnover of 20:4n-6 into brain phospholipid pools were markedly reduced...

  6. A New Acylated Flavonol Glycoside from Chenopodium foliosum

    Directory of Open Access Journals (Sweden)

    Zlatina Kokanova-Nedialkova, , , , , and

    2014-07-01

    Full Text Available A new acylated flavonol glycoside, namely gomphrenol-3-O-( 5 '''-O-E-feruloyl-β-D-apiofuranosyl-(1→2[β-D-glucopyranosyl-(1→6]-β-D-glucopyranoside (1 was isolated from the aerial parts of Chenopodium foliosum Asch. The structure of 1 was determined by means of spectroscopic methods (1D and 2D NMR, UV, IR, and HRESIMS. Radical scavenging and antioxidant activities of 1 were established using DPPH and ABTS radicals, FRAP assay and inhibition of lipid peroxidation (LP in linoleic acid system by the ferric thiocyanate method. Compound 1 showed low activity (DPPH and ABTS or lack of activity (FRAP and LP. In combination with CCl 4, 1 reduced the damage caused by the hepatotoxic agent and preserved cell viability and GSH level, decreased LDH leakage and reduced lipid damage. Effects were concentration dependent, most visible at the highest concentration (100 µg/m L , and similar to those of silymarin .

  7. An acylated phloroglucinol with antimicrobial properties from Helichrysum caespititium.

    Science.gov (United States)

    Mathekga, A D; Meyer, J J; Horn, M M; Drewes, S E

    2000-01-01

    A new acylated form of a phloroglucinol with significant antimicrobial properties was isolated by bioactivity guided fractionation from Helichrysum caespititium (Asteraceae). The structure elucidation, and conformation of the new phloroglucinol, 2-methyl-4-[2',4',6'-trihydroxy-3'-(2-methylpropanoyl) phenyl]but-2-enyl acetate, was established by high field NMR spectroscopic and MS data. The compound inhibited growth of Bacillus cereus, B. pumilus, B. subtilis and Micrococcus kristinae at the very low concentration of 0.5 microg/ml and Staphylococcus aureus at 5.0 microg/ml. Six fungi tested were similarly inhibited at low MICs, Aspergillus flavus and A. niger (1.0 microg/ml), Cladosporium chladosporioides (5 microg/ml), C. cucumerinum and C. sphaerospermum (0.5 microg/ml) and Phylophthora capsici at 1.0 microg/ml. PMID:10656414

  8. Acyl-Homoserine Lactone Quorum Sensing in the Roseobacter Clade

    Directory of Open Access Journals (Sweden)

    Jindong Zan

    2014-01-01

    Full Text Available Members of the Roseobacter clade are ecologically important and numerically abundant in coastal environments and can associate with marine invertebrates and nutrient-rich marine snow or organic particles, on which quorum sensing (QS may play an important role. In this review, we summarize current research progress on roseobacterial acyl-homoserine lactone-based QS, particularly focusing on three relatively well-studied representatives, Phaeobacter inhibens DSM17395, the marine sponge symbiont Ruegeria sp. KLH11 and the dinoflagellate symbiont Dinoroseobacter shibae. Bioinformatic survey of luxI homologues revealed that over 80% of available roseobacterial genomes encode at least one luxI homologue, reflecting the significance of QS controlled regulatory pathways in adapting to the relevant marine environments. We also discuss several areas that warrant further investigation, including studies on the ecological role of these diverse QS pathways in natural environments.

  9. Small Antimicrobial Agents Based on Acylated Reduced Amide Scaffold.

    Science.gov (United States)

    Teng, Peng; Huo, Da; Nimmagadda, Alekhya; Wu, Jianfeng; She, Fengyu; Su, Ma; Lin, Xiaoyang; Yan, Jiyu; Cao, Annie; Xi, Chuanwu; Hu, Yong; Cai, Jianfeng

    2016-09-01

    Prevalence of drug-resistant bacteria has emerged to be one of the greatest threats in the 21st century. Herein, we report the development of a series of small molecular antibacterial agents that are based on the acylated reduced amide scaffold. These molecules display good potency against a panel of multidrug-resistant Gram-positive and Gram-negative bacterial strains. Meanwhile, they also effectively inhibit the biofilm formation. Mechanistic studies suggest that these compounds kill bacteria by compromising bacterial membranes, a mechanism analogous to that of host-defense peptides (HDPs). The mechanism is further supported by the fact that the lead compounds do not induce resistance in MRSA bacteria even after 14 passages. Lastly, we also demonstrate that these molecules have therapeutic potential by preventing inflammation caused by MRSA induced pneumonia in a rat model. This class of compounds could lead to an appealing class of antibiotic agents combating drug-resistant bacterial strains. PMID:27526720

  10. Synthesis of acyl derivatives of salicin, salirepin, and arbutin.

    Science.gov (United States)

    Stepanova, Elena V; Belyanin, Maxim L; Filimonov, Victor D

    2014-03-31

    The total synthesis of two natural phenolglycosides of the family Salicaceae, namely: populoside and 2-(β-d-glucopyranosyloxy)-5-hydroxy benzyl (3-methoxy-4-hydroxy) cinnamoate and nine not found yet in plants acyl derivatives of phenoglycosides: 2-(β-d-glucopyranosyloxy)-benzylcinnamoate, 2-(β-d-glucopyranosyloxy)-benzyl (4-hydroxy) benzoate, 2-(β-d-glucopyranosyloxy)-benzyl (3-methoxy-4-hydroxy) benzoate, 2-(β-d-glucopyranosyloxy)-5-hydroxy benzyl (3,4-dihydroxy) cinnamoate, 2-(β-d-glucopyranosyloxy)-5-hydroxy benzylcinnamoate, 2-(β-d-glucopyranosyloxy)-5-hydroxy benzyl (4-hydroxy) benzoate, 2-(β-d-glucopyranosyloxy)-5-hydroxy benzyl (3-methoxy-4-hydroxy) benzoate, 2-(β-d-glucopyranosyloxy)-5-benzoyloxy benzylbenzoate and 4-(β-d-glucopyranosyloxy)-phenylbenzoate, starting from readily available phenols and glucose was developed for the first time.

  11. Synthesis of acyl derivatives of salicin, salirepin, and arbutin.

    Science.gov (United States)

    Stepanova, Elena V; Belyanin, Maxim L; Filimonov, Victor D

    2014-03-31

    The total synthesis of two natural phenolglycosides of the family Salicaceae, namely: populoside and 2-(β-d-glucopyranosyloxy)-5-hydroxy benzyl (3-methoxy-4-hydroxy) cinnamoate and nine not found yet in plants acyl derivatives of phenoglycosides: 2-(β-d-glucopyranosyloxy)-benzylcinnamoate, 2-(β-d-glucopyranosyloxy)-benzyl (4-hydroxy) benzoate, 2-(β-d-glucopyranosyloxy)-benzyl (3-methoxy-4-hydroxy) benzoate, 2-(β-d-glucopyranosyloxy)-5-hydroxy benzyl (3,4-dihydroxy) cinnamoate, 2-(β-d-glucopyranosyloxy)-5-hydroxy benzylcinnamoate, 2-(β-d-glucopyranosyloxy)-5-hydroxy benzyl (4-hydroxy) benzoate, 2-(β-d-glucopyranosyloxy)-5-hydroxy benzyl (3-methoxy-4-hydroxy) benzoate, 2-(β-d-glucopyranosyloxy)-5-benzoyloxy benzylbenzoate and 4-(β-d-glucopyranosyloxy)-phenylbenzoate, starting from readily available phenols and glucose was developed for the first time. PMID:24632218

  12. Study on Separation of Tapered Concentrators Using Shrinkage Chute Group%用尖缩溜槽组模拟圆锥选矿机的研究

    Institute of Scientific and Technical Information of China (English)

    张军; 汤玉和; 罗传胜; 张凤华

    2011-01-01

    圆锥选矿机处理量大,但试验条件比较复杂,制约了其推广应用.通过分析圆锥选矿机和尖缩溜槽的原理、特点,对尖缩溜槽进行优化,并将某钒钛磁铁矿选厂采用的3DS6FD圆锥选矿机与依照3DS6FD圆锥选矿机的内部流程段数配置优化后的尖缩溜槽组进行对比试验,结果表明在实验室中可以用优化的尖缩溜槽组替代圆锥选矿机进行模拟试验研究,用来分析、说明和研究某些低品位矿石是否适合采用圆锥选矿机来处理,以及探索、优化某些老厂推广应用圆锥选矿机的技术改造的可行性.%Big capacity is advantage of tapered concentrators, but one disadvantage of application of tapered concentrators.Analyzed the principle, characteristics of tapered concentrators and sharp shrinkage chute and optimized the sharp shrinkage chute.Comparative tests have been done between the optimized sharp shrinkage chute group according to the 3DS6FD tapered concentrators In the laboratory and 3DS6FD tapered concentrators in one titanium magnetite factory.Results indicate that in the lab the 3DS6FD tapered concentrators can be replaced with optimized sharp shrinkage chute group to study, analysis, description and study some minerals beneficiation of low grade ores being suitable or unsuitable for using tapered concentrators to handle.And whether apphcation of tapered concentrators could be used or not be used for optimizing and exploring mineral processing technology in some old plant.

  13. Emergence of a sylvatic enzootic formosan ferret badger-associated rabies in Taiwan and the geographical separation of two phylogenetic groups of rabies viruses.

    Science.gov (United States)

    Tsai, K J; Hsu, W C; Chuang, W C; Chang, J C; Tu, Y C; Tsai, H J; Liu, H F; Wang, F I; Lee, S H

    2016-01-15

    Taiwan had been declared rabies-free in humans and domestic animals for five decades until July 2013, when surprisingly, three Formosan ferret badgers (FB) were diagnosed with rabies. Since then, a variety of wild carnivores and other wildlife species have been found dead, neurologically ill, or exhibiting aggressive behaviors around the island. To determine the affected animal species, geographic areas, and environments, animal bodies were examined for rabies by direct fluorescent antibody test (FAT). The viral genomes from the brains of selected rabid animals were sequenced for the phylogeny of rabies viruses (RABV). Out of a total of 1016 wild carnivores, 276/831 (33.2%) Formosan FBs were FAT positive, with occasional biting incidents in 1 dog and suspected spillover in 1 house shrew. All other animals tested, including dogs, cats, bats, mice, house shrews, and squirrels, were rabies-negative. The rabies was badger-associated and confined to nine counties/cities in sylvatic environments. Phylogeny of nucleoprotein and glycoprotein genes from 59 Formosan FB-associated RABV revealed them to be clustered in two distinct groups, TWI and TWII, consistent with the geographic segregation into western and eastern Taiwan provided by the Central Mountain Range and into northern rabies-free and central-southern rabies-affected regions by a river bisecting western Taiwan. The unique features of geographic and genetic segregation, sylvatic enzooticity, and FB-association of RABV suggest a logical strategy for the control of rabies in this nation. PMID:26711025

  14. Interfacial Behavior of Fatty-Acylated Sericin Prepared by Lipase-Catalyzed Solid-Phase Synthesis

    OpenAIRE

    Ogino, Masato; Tanaka, Rie; 服部, 誠; Yoshida, Tadashi; 横手, よし子; 高橋, 幸資

    2006-01-01

    Fatty-acylated sericin {1:0.7 molar ratio of sericin (Mr 18,700) to oleic acid} was prepared by lipase-catalyzed solid-phase synthesis in n-hexane containing oleic acid to endow sericin with interfacial properties. Acylation with oleic acid was confirmed by 1H-NMR. The fatty-acylated sericin exhibited superior emulsifying activity index and emulsion stability in the presence of 0?0.5 M NaCl, in a temperature range of 30?80 °C and pH range of 2?7, as compared with the control sericin. The fatt...

  15. Accumulation of N-acyl-ethanolamine phospholipids in rat brains during post-decapitative ischemia

    DEFF Research Database (Denmark)

    Moesgaard, B.; Hansen, Harald S.; Jaroszewski, J.W.

    1999-01-01

    Phosphorus-31 nuclear magnetic resonance (P NMR) spectroscopy has been used to study accumulation of N-acyl-ethanolamine phospholipids in rat brains during post-decapitative ischemia. Lipids were extracted from rat brain homogenates and the extracts were thoroughly washed with aq. potassium......-phospho(N-acyl)-ethanolamine (NAPE(PLAS)), respectively, by spiking with authentic materials. Additionally, the identification was verified by thin-layer chromatography, which also showed the accumulation of N-acyl-ethanolamine phospholipids. The use of K-EDTA instead of the commonly used Cs...

  16. CENTRIFUGAL SEPARATORS

    Science.gov (United States)

    Skarstrom, C.

    1959-03-10

    A centrifugal separator is described for separating gaseous mixtures where the temperature gradients both longitudinally and radially of the centrifuge may be controlled effectively to produce a maximum separation of the process gases flowing through. Tbe invention provides for the balancing of increases and decreases in temperature in various zones of the centrifuge chamber as the result of compression and expansions respectively, of process gases and may be employed effectively both to neutralize harmful temperature gradients and to utilize beneficial temperaturc gradients within the centrifuge.

  17. 石家庄陕鼓2×40000m^3/h空分设备设计优化%Optimized design of Shijiazhuang Shaanxi Blower Group 2 ×40000m^3/h air separation plant

    Institute of Scientific and Technical Information of China (English)

    张岑; 卢子学

    2012-01-01

    At design stage of Shijiazhuang Shaanxi Blower Group 2 ×40000m^3/h air separation plants, it found unreasonable design in the nitrogen compression and supply system, air compressor vent silencer, and connection mode for feeding boosted air to plate-fin type heat exchanger, as well as the factors impairing stable and safe operation of the product continuous supply and air separation plant. Here, the optimization measures taken for the unreasonable factors are described, which puts a sound basis for stable run of the air separation plant.%在石家庄陕鼓2×40000m^3/h空分设备设计阶段,发现氮气压缩和供应系统、空压机放空消声器以及增压空气进板翅式换热器的连接方式设计不舍理,存在影响产品连续供应和空分设备稳定、安全运行的因素。介绍对这些不合理因素所采取的优化措施,为空分设备建成后稳定运行奠定基础。

  18. Group separation of transplutonium and rare earth elements by liquid chromatography with free stationary phase using 2,4,6-tris[ditolylphosphoryl] - 1,3,5 - triazine as extractant

    International Nuclear Information System (INIS)

    Methods of group separation of trace amounts of transplutonium elements (TPE) and weight amounts of rare earth elements (REE) in the systems on the basis of bifunctional neutral organophosphoric compounds by the method of liquid chromatography with a free stationary phase have been developed. When solution of 2,4,6 - tris[ditolylphosphoryl] - 1,3,5 - triazine in chloroform was used as stationary phase, REE were the first to be washed out by 0.5 mol/l NH4SCN-1 mol/l HCl solution, then TPE - by 0.025 mol/l of oxyethylidenediphosphonic acid in water. the fractions contained about 100% of one of the groups without impurity of the other. 7 refs.; 6 figs

  19. Antioxidant Potential of Anthrarobin (1, 2, 10 trihydroxy anthracene) and its Acyl Derivatives

    International Nuclear Information System (INIS)

    The current study explores the antioxidant potential of anthrarobin and its synthesized derivatives determined by various methods including DPPH radical scavenging ability, reducing power and superoxide scavenging activity. Anthrarobin was acetylated with acetic anhydride in the presence of pyridine to afford anthracen-1, 10-dihydroxy-2-acetate (1), anthracen-1-hydroxy-2, 10-diacetate (2) and anthracen-1, 2, 10-triacetate (3). Anthrarobin exhibited good antioxidant potential with 68 and 78% at 50 meuM and 100 meuM concentrations, respectively. Reducing power of anthrarobin increases with increase in concentration in a dose-dependent manner as could be seen from 37 and 54% activity at the concentration of 50 and 100 meuM, respectively. 3-Tetra-butyl-4-hydroxyanisole (BHA) used as standard showed 84 and 93% activities at 50 and 100 meuM, respectively. BHA and anthrarobin were compared to determine that how much superoxide radicals were scavenged in alkaline DMSO by different concentrations. It was found that 50 meuM of anthrarobin was needed to scavenge 50% radicals while 12.5 meuM of BHA scavenged 50% radicals in DMSO. It is concluded that anthrarobin has highest antioxidant potential as compared to its derivatives. It is postulated that position and numbers of hydroxyl group in anthrarobin are responsible for antioxidant potential and the activity decreases with the substitution of acyl groups at various positions in synthesized derivatives. (author)

  20. Separations chemistry

    International Nuclear Information System (INIS)

    Results of studies on the photochemistry of aqueous Pu solutions and the stability of iodine in liquid and gaseous CO2 are reported. Progress is reported in studies on: the preparation of macroporous bodies filled with oxides and sulfides to be used as adsorbents; the beneficiation of photographic wastes; the anion exchange adsorption of transition elements from thiosulfate solutions; advanced filtration applications of energy significance; high-resolution separations; and, the examination of the separation agents, octylphenylphosphoric acid (OPPA) and trihexyl phosphate (THP)

  1. Product separator

    Science.gov (United States)

    Welsh, Robert A.; Deurbrouck, Albert W.

    1976-01-20

    A secondary light sensitive photoelectric product separator for use with a primary product separator that concentrates a material so that it is visually distinguishable from adjacent materials. The concentrate separation is accomplished first by feeding the material onto a vibratory inclined surface with a liquid flow, such as a wet concentrating table. Vibrations generally perpendicular to the stream direction of flow cause the concentrate to separate from its mixture according to its color. When the concentrate and its surrounding stream reach the recovery end of the table, a detecting device notes the line of color demarcation and triggers a signal if it differs from a normal condition. If no difference is noted nothing moves on the second separator. However, if a difference is detected in the constant monitoring of the color line's location, a product splitter and recovery unit normally positioned near the color line at the recovery end, moves to a new position. In this manner the selected separated concentrate is recovered at a maximum rate regardless of variations in the flow stream or other conditions present.

  2. Vectorial acylation in Saccharomyces cerevisiae. Fat1p and fatty acyl-CoA synthetase are interacting components of a fatty acid import complex

    DEFF Research Database (Denmark)

    Zou, Zhiying; Tong, Fumin; Færgeman, Nils J.;

    2003-01-01

    In Saccharomyces cerevisiae Fat1p and fatty acyl-CoA synthetase (FACS) are hypothesized to couple import and activation of exogenous fatty acids by a process called vectorial acylation. Molecular genetic and biochemical studies were used to define further the functional and physical interactions...... and Fat1p play distinct roles in the fatty acid import process. When expressed from a 2-mu plasmid, Fat1p contributes significant oleoyl-CoA synthetase activity, which indicates vectorial esterification and metabolic trapping are the driving forces behind import. Evidence of a physical interaction between...... as trap were active when tested using the yeast two-hybrid system. Third, co-expressed, differentially tagged Fat1p and Faa1p or Faa4p were co-immunoprecipitated. Collectively, these data support the hypothesis that fatty acid import by vectorial acylation in yeast requires a multiprotein complex, which...

  3. Fat Metabolism in Higher Plants: LXII. Stearl-acyl Carrier Protein Desaturase from Spinach Chloroplasts.

    Science.gov (United States)

    Jacobson, B S; Jaworski, J G; Stumpf, P K

    1974-10-01

    Stearyl-acyl carrier protein desaturase (EC 1.14.99.6), present in the stroma fraction of spinach (Spinacia oleracea) chloroplasts, rapidly desaturated enzymatically prepared stearyl-acyl carrier protein to oleic acid. No other substrates were desaturated. In addition to stearyl-acyl carrier protein, reduced ferredoxin was an essential component of the system. The electron donor systems were either ascorbate, dichlorophenolindophenol, photosystem I and light, or NADPH and ferredoxin-NADP reductase. The desaturase was more active in extracts prepared from chloroplasts obtained from immature spinach leaves than from mature leaves. Stearyl-acyl carrier protein desaturase also occurs in soluble extracts of avocado (Persea americana Mill.) mesocarp and of developing safflower (Carthamus tinctorius) seeds.

  4. A Scalable Method for Regioselective 3-Acylation of 2-Substituted Indoles under Basic Conditions

    DEFF Research Database (Denmark)

    Johansson, Karl Henrik; Urruticoechea, Andoni; Larsen, Inna;

    2015-01-01

    Privileged structures such as 2-arylindoles are recurrent molecular scaffolds in bioactive molecules. We here present an operationally simple, high yielding and scalable method for regioselective 3-acylation of 2-substituted indoles under basic conditions using functionalized acid chlorides. The ...

  5. Long-chain acyl-homoserine lactones from Methylobacterium mesophilicum: synthesis and absolute configuration.

    Science.gov (United States)

    Pomini, Armando M; Cruz, Pedro L R; Gai, Cláudia; Araújo, Welington L; Marsaioli, Anita J

    2009-12-01

    The acyl-homoserine lactones (acyl-HSLs) produced by Methylobacterium mesophilicum isolated from orange trees infected with the citrus variegated chlorosis (CVC) disease have been studied, revealing the occurrence of six long-chain acyl-HSLs, i.e., the saturated homologues (S)-N-dodecanoyl (1) and (S)-N-tetradecanoyl-HSL (5), the uncommon odd-chain N-tridecanoyl-HSL (3), the new natural product (S)-N-(2E)-dodecenoyl-HSL (2), and the rare unsaturated homologues (S)-N-(7Z)-tetradecenoyl (4) and (S)-N-(2E,7Z)-tetradecadienyl-HSL (6). The absolute configurations of all HSLs were determined as 3S. Compounds 2 and 6 were synthesized for the first time. Antimicrobial assays with synthetic acyl-HSLs against Gram-positive bacterial endophytes co-isolated with M. mesophilicum from CVC-infected trees revealed low or no antibacterial activity. PMID:19919062

  6. Very long chain acyl-coenzyme A dehydrogenase deficiency with adult onset

    DEFF Research Database (Denmark)

    Smelt, A H; Poorthuis, B J; Onkenhout, W;

    1998-01-01

    Very long chain acyl-coenzyme A (acyl-CoA) dehydrogenase (VLCAD) deficiency is a severe disorder of mitochondrial beta-oxidation in infants. We report adult onset of attacks of painful rhabdomyolysis. Gas chromatography identified strongly elevated levels of tetradecenoic acid, 14:1(n-9), tetrade...... be due to residual enzyme activity as a consequence of the two missense mutations. Treatment with L-carnitine and medium chain triglycerides in the diet did not reduce the attacks of rhabdomyolysis.......Very long chain acyl-coenzyme A (acyl-CoA) dehydrogenase (VLCAD) deficiency is a severe disorder of mitochondrial beta-oxidation in infants. We report adult onset of attacks of painful rhabdomyolysis. Gas chromatography identified strongly elevated levels of tetradecenoic acid, 14:1(n-9...

  7. Selective Acylation Enhances Membrane Charge Sensitivity of the Antimicrobial Peptide Mastoparan-X

    DEFF Research Database (Denmark)

    Etzerodt, Thomas Povl; Henriksen, Jonas Rosager; Rasmussen, Palle;

    2011-01-01

    and positioning of the peptide in the membrane caused by either PA or OA acylation play a critical role in the fine-tuning of the effective charge of the peptide and thereby the fine-tuning of the peptide's selectivity between neutral and negatively charged lipid membranes. This finding is unique compared......The partitioning of the wasp venom peptide mastoparan-X (MPX) into neutral and negatively charged lipid membranes has been compared with two new synthetic analogs of MPX where the Nα-terminal of MPX was acylated with propanoic acid (PA) and octanoic acid (OA). The acylation caused a considerable...... change in the membrane partitioning properties of MPX and it was found that the shorter acylation with PA gave improved affinity and selectivity toward negatively charged membranes, whereas OA decreased the selectivity. Based on these findings, we hypothesize that minor differences in the embedding...

  8. The Acute Effects of Swimming on Appetite, Food Intake, and Plasma Acylated Ghrelin

    Directory of Open Access Journals (Sweden)

    James A. King

    2011-01-01

    Full Text Available Swimming may stimulate appetite and food intake but empirical data are lacking. This study examined appetite, food intake, and plasma acylated ghrelin responses to swimming. Fourteen healthy males completed a swimming trial and a control trial in a random order. Sixty min after breakfast participants swam for 60 min and then rested for six hours. Participants rested throughout the control trial. During trials appetite was measured at 30 min intervals and acylated ghrelin was assessed periodically (0, 1, 2, 3, 4, 6, and 7.5 h. =10. Appetite was suppressed during exercise before increasing in the hours after. Acylated ghrelin was suppressed during exercise. Swimming did not alter energy or macronutrient intake assessed at buffet meals (total trial energy intake: control 9161 kJ, swimming 9749 kJ. These findings suggest that swimming stimulates appetite but indicate that acylated ghrelin and food intake are resistant to change in the hours afterwards.

  9. Enhanced Activity of Nanocrystalline Beta Zeolite for Acylation of Veratrole with Acetic Anhydride.

    Science.gov (United States)

    Aisha Mahmood Abdulkareem, Al-Turkustani; Selvin, Rosilda

    2016-04-01

    Friedel-Craft acylation of veratrole using homogeneous acid catalysts such as AlCl3, FeCl3, ZnCl2, and HF etc. produces acetoveratrone, (3',4'-dimethoxyacetophenone), which is the intermediate for synthesis of papavarine alkaloids. The problems associated with these homogeneous catalysts can be overcome by using heterogeneous solid catalysts. Since acetoveratrone is a larger molecule, large pore Beta zeolites with smaller particle sizes are beneficial for the liquid-phase acylation of veratrole, for easy diffusion of reactants and products. The present study aims in the acylation of veratrole with acetic anhydride using nanocrystalline Beta Zeolite catalyst. A systematic investigation of the effects of various reaction parameters was done. The catalysts were characterized for their structural features by using XRD, TEM and DLS analyses. The catalytic activity of nanocrystalline Beta zeolite was compared with commercial Beta zeolite for the acylation and was found that nanocrystalline Beta zeolite possessed superior activity.

  10. Eradication of Helicobacter pylori increases childhood growth and serum acylated ghrelin levels

    OpenAIRE

    Yang, Yao-Jong; Sheu, Bor-Shyang; Yang, Hsiao-Bai; Lu, Cheng-Chan; Chuang, Ching-Chun

    2012-01-01

    AIM: To determine whether Helicobacter pylori (H. pylori)-infected children have reduced body weight (BW) and height (BH) growth, and if H. pylori eradication may restore growth while improving serum acylated ghrelin.

  11. A liver-specific defect of Acyl-CoA degradation produces hyperammonemia, hypoglycemia and a distinct hepatic Acyl-CoA pattern.

    Directory of Open Access Journals (Sweden)

    Nicolas Gauthier

    Full Text Available Most conditions detected by expanded newborn screening result from deficiency of one of the enzymes that degrade acyl-coenzyme A (CoA esters in mitochondria. The role of acyl-CoAs in the pathophysiology of these disorders is poorly understood, in part because CoA esters are intracellular and samples are not generally available from human patients. We created a mouse model of one such condition, deficiency of 3-hydroxy-3-methylglutaryl-CoA lyase (HL, in liver (HLLKO mice. HL catalyses a reaction of ketone body synthesis and of leucine degradation. Chronic HL deficiency and acute crises each produced distinct abnormal liver acyl-CoA patterns, which would not be predictable from levels of urine organic acids and plasma acylcarnitines. In HLLKO hepatocytes, ketogenesis was undetectable. Carboxylation of [2-(14C] pyruvate diminished following incubation of HLLKO hepatocytes with the leucine metabolite 2-ketoisocaproate (KIC. HLLKO mice also had suppression of the normal hyperglycemic response to a systemic pyruvate load, a measure of gluconeogenesis. Hyperammonemia and hypoglycemia, cardinal features of many inborn errors of acyl-CoA metabolism, occurred spontaneously in some HLLKO mice and were inducible by administering KIC. KIC loading also increased levels of several leucine-related acyl-CoAs and reduced acetyl-CoA levels. Ultrastructurally, hepatocyte mitochondria of KIC-treated HLLKO mice show marked swelling. KIC-induced hyperammonemia improved following administration of carglumate (N-carbamyl-L-glutamic acid, which substitutes for the product of an acetyl-CoA-dependent reaction essential for urea cycle function, demonstrating an acyl-CoA-related mechanism for this complication.

  12. Specificity of acyl-homoserine lactone synthases examined by mass spectrometry.

    Science.gov (United States)

    Gould, Ty A; Herman, Jake; Krank, Jessica; Murphy, Robert C; Churchill, Mair E A

    2006-01-01

    Many gram-negative bacteria produce a specific set of N-acyl-L-homoserine-lactone (AHL) signaling molecules for the purpose of quorum sensing, which is a means of regulating coordinated gene expression in a cell-density-dependent manner. AHLs are produced from acylated acyl-carrier protein (acyl-ACP) and S-adenosyl-L-methionine by the AHL synthase enzyme. The appearance of specific AHLs is due in large part to the intrinsic specificity of the enzyme for subsets of acyl-ACP substrates. Structural studies of the Pantoea stewartii enzyme EsaI and AHL-sensitive bioassays revealed that threonine 140 in the acyl chain binding pocket directs the enzyme toward production of 3-oxo-homoserine lactones. Mass spectrometry was used to examine the range of AHL molecular species produced by AHL synthases under a variety of conditions. An AHL selective normal-phase chromatographic purification with addition of a deuterated AHL internal standard was followed by reverse-phase liquid chromatography-tandem mass spectrometry in order to obtain estimates of the relative amounts of different AHLs from biological samples. The AHLs produced by wild-type and engineered EsaI and LasI AHL synthases show that intrinsic specificity and different cellular conditions influence the production of AHLs. The threonine at position 140 in EsaI is important for the preference for 3-oxo-acyl-ACPs, but the role of the equivalent threonine in LasI is less clear. In addition, LasI expressed in Escherichia coli produces a high proportion of unusual AHLs with acyl chains consisting of an odd number of carbons. Furthermore, these studies offer additional methods that will be useful for surveying and quantitating AHLs from different sources. PMID:16385066

  13. LuxR homolog-independent gene regulation by acyl-homoserine lactones in Pseudomonas aeruginosa.

    Science.gov (United States)

    Chugani, Sudha; Greenberg, Everett Peter

    2010-06-01

    Pseudomonas aeruginosa quorum control of gene expression involves three LuxR-type signal receptors LasR, RhlR, and QscR that respond to the LasI- and RhlI-generated acyl-homoserine lactone (acyl-HSL) signals 3OC12-HSL and C4-HSL. We found that a LasR-RhlR-QscR triple mutant responds to acyl-HSLs by regulating at least 37 genes. LuxR homolog-independent activation of the representative genes antA and catB also occurs in the wild type. Expression of antA was influenced the most by C10-HSL and to a lesser extent by other acyl-HSLs, including the P. aeruginosa 3OC12-HSL and C4-HSL signals. The ant and cat operons encode enzymes for the degradation of anthranilate to tricarboxylic acid cycle intermediates. Our results indicate that LuxR homolog-independent acyl-HSL control of the ant and cat operons occurs via regulation of antR, which codes for the transcriptional activator of the ant operon. Although P. aeruginosa has multiple pathways for anthranilate synthesis, one pathway-the kynurenine pathway for tryptophan degradation-is required for acyl-HSL activation of the ant operon. The kynurenine pathway is also the critical source of anthranilate for energy metabolism via the antABC gene products, as well as the source of anthranilate for synthesis of the P. aeruginosa quinolone signal. Our discovery of LuxR homolog-independent responses to acyl-HSLs provides insight into acyl-HSL signaling. PMID:20498077

  14. Acyl Meldrum's acid derivatives: application in organic synthesis

    International Nuclear Information System (INIS)

    This review is focused on an important class of Meldrum's acid derivatives commonly known as acyl Meldrum's acids. The preparation methods of these compounds are considered including the recently proposed and rather rarely used ones. The chemical properties of acyl Meldrum's acids are described in detail, including thermal stability and reactions with various nucleophiles. The possible mechanisms of these transformations are analyzed. The bibliography includes 134 references

  15. Inhibition of DNA–Topoisomerase I by Acylated Triterpene Saponins from Pittosporum angustifolium Lodd.

    OpenAIRE

    Baecker, C; Drwal, M.N.; Preissner, R; Lindequist, U.

    2016-01-01

    Abstract Previous phytochemical investigation of the leaves and seeds of Pittosporum angustifolium Lodd. led to the isolation and structural elucidation of polyphenols and triterpene saponins. Evaluation for cytotoxicity of isolated saponins revealed that the predominant structural feature for a cytotoxic activity are acyl substituents at the oleanane aglycon backbone. The present work reports the results of a screening of 10 selected acylated saponins for their potential to inhibit the human...

  16. The Acute Effects of Swimming on Appetite, Food Intake, and Plasma Acylated Ghrelin

    OpenAIRE

    Stensel, David J.; Wasse, Lucy K.; King, James A

    2011-01-01

    Swimming may stimulate appetite and food intake but empirical data are lacking. This study examined appetite, food intake, and plasma acylated ghrelin responses to swimming. Fourteen healthy males completed a swimming trial and a control trial in a random order. Sixty min after breakfast participants swam for 60 min and then rested for six hours. Participants rested throughout the control trial. During trials appetite was measured at 30 min intervals and acylated ghrelin was assessed periodic...

  17. Fatty acid acylation of proteins: specific roles for palmitic, myristic and caprylic acids

    Directory of Open Access Journals (Sweden)

    Rioux Vincent

    2016-05-01

    Full Text Available Fatty acid acylation of proteins corresponds to the co- or post-translational covalent linkage of an acyl-CoA, derived from a fatty acid, to an amino-acid residue of the substrate protein. The cellular fatty acids which are involved in protein acylation are mainly saturated fatty acids. Palmitoylation (S-acylation corresponds to the reversible attachment of palmitic acid (C16:0 via a thioester bond to the side chain of a cysteine residue. N-terminal myristoylation refers to the covalent attachment of myristic acid (C14:0 by an amide bond to the N-terminal glycine of many eukaryotic and viral proteins. Octanoylation (O-acylation typically concerns the formation of an ester bond between octanoic acid (caprylic acid, C8:0 and the side chain of a serine residue of the stomach peptide ghrelin. An increasing number of proteins (enzymes, hormones, receptors, oncogenes, tumor suppressors, proteins involved in signal transduction, eukaryotic and viral structural proteins have been shown to undergo fatty acid acylation. The addition of the acyl moiety is required for the protein function and usually mediates protein subcellular localization, protein-protein interaction or protein-membrane interaction. Therefore, through the covalent modification of proteins, these saturated fatty acids exhibit emerging specific and important roles in modulating protein functions. This review provides an overview of the recent findings on the various classes of protein acylation leading to the biological ability of saturated fatty acids to regulate many pathways. Finally, the nutritional links between these elucidated biochemical mechanisms and the physiological roles of dietary saturated fatty acids are discussed.

  18. Pharmacokinetics of naproxen, its metabolite O-desmethylnaproxen, and their acyl glucuronides in humans.

    Science.gov (United States)

    Vree, T B; van den Biggelaar-Martea, M; Verwey-van Wissen, C P; Vree, J B; Guelen, P J

    1993-08-01

    The aim of this investigation was to assess the pharmacokinetics of naproxen in 10 human subjects after an oral dose of 500 mg using a direct HPLC analysis of the acyl glucuronide conjugates of naproxen and its metabolite O-desmethylnaproxen. The mean t1/2 of naproxen in 9 subjects was 24.7 +/- 6.4 h (range 16 to 36 h). The t1/2 of 7.4 as found in subject number 10 must, therefore, be regarded as an extraordinary case (p < 0.0153). Naproxen acyl glucuronide accounts for 50.8 +/- 7.32 per cent of the dose, its isomerized conjugate isoglucuronide for 6.5 +/- 2.0 per cent, O-desmethylnaproxen acyl glucuronide for 14.3 +/- 3.4 per cent, and its isoglucuronide for 5.5 +/- 1.3 per cent (n = 10; 100 h collection period). Naproxen and O-desmethylnaproxen are excreted in negligible amounts (< 1 per cent). Even though urine pH of the subjects was kept acid (range pH 5.0-5.5) in order to stabilize the acyl glucuronides, isomerization takes place in blood when the acyl glucuronide is released from the liver for excretion by the kidney. Binding to plasma proteins was measured as 98 per cent and 100 per cent, respectively for the unconjugated compounds naproxen and O-desmethylnaproxen. Binding of the acyl glucuronides was less, being 92 per cent; for naproxen acyl glucuronide, 66 per cent for naproxen isoglucuronide, 72 per cent for O-desmethylnaproxen acyl glucuronide and 42 per cent for O-desmethylnaproxen isoglucuronide. PMID:8218967

  19. New N-acyl taurine from the sea urchin Glyptocidaris crenularis.

    Science.gov (United States)

    Zhou, Xuefeng; Xu, Tunhai; Wen, Kewei; Yang, Xian-Wen; Xu, Shi-Hai; Liu, Yonghong

    2010-01-01

    A new N-acyl taurine (1), together with a new natural product, l-(beta-D-ribofuranosyl)-1,2,4-triazole (4), and two known compounds (2 and 3), were isolated from the sea urchin, Glyptocidaris crenularis. The new N-acyl taurine was elucidated as 2-(5R,15S-dihydroxyeicosanoylamino) ethanesulfonic acid on the basis of spectroscopic (NMR, MS) analyses and the modified Mosher ester method. Compound 2 showed significant toxicity against brine shrimp larvae.

  20. Deciphering the acylation pattern of Yersinia enterocolitica lipid A.

    Directory of Open Access Journals (Sweden)

    Mar Reinés

    Full Text Available Pathogenic bacteria may modify their surface to evade the host innate immune response. Yersinia enterocolitica modulates its lipopolysaccharide (LPS lipid A structure, and the key regulatory signal is temperature. At 21°C, lipid A is hexa-acylated and may be modified with aminoarabinose or palmitate. At 37°C, Y. enterocolitica expresses a tetra-acylated lipid A consistent with the 3'-O-deacylation of the molecule. In this work, by combining genetic and mass spectrometric analysis, we establish that Y. enterocolitica encodes a lipid A deacylase, LpxR, responsible for the lipid A structure observed at 37°C. Western blot analyses indicate that LpxR exhibits latency at 21°C, deacylation of lipid A is not observed despite the expression of LpxR in the membrane. Aminoarabinose-modified lipid A is involved in the latency. 3-D modelling, docking and site-directed mutagenesis experiments showed that LpxR D31 reduces the active site cavity volume so that aminoarabinose containing Kdo(2-lipid A cannot be accommodated and, therefore, not deacylated. Our data revealed that the expression of lpxR is negatively controlled by RovA and PhoPQ which are necessary for the lipid A modification with aminoarabinose. Next, we investigated the role of lipid A structural plasticity conferred by LpxR on the expression/function of Y. enterocolitica virulence factors. We present evidence that motility and invasion of eukaryotic cells were reduced in the lpxR mutant grown at 21°C. Mechanistically, our data revealed that the expressions of flhDC and rovA, regulators controlling the flagellar regulon and invasin respectively, were down-regulated in the mutant. In contrast, the levels of the virulence plasmid (pYV-encoded virulence factors Yops and YadA were not affected in the lpxR mutant. Finally, we establish that the low inflammatory response associated to Y. enterocolitica infections is the sum of the anti-inflammatory action exerted by pYV-encoded YopP and the

  1. Endogenous N-acyl taurines regulate skin wound healing.

    Science.gov (United States)

    Sasso, Oscar; Pontis, Silvia; Armirotti, Andrea; Cardinali, Giorgia; Kovacs, Daniela; Migliore, Marco; Summa, Maria; Moreno-Sanz, Guillermo; Picardo, Mauro; Piomelli, Daniele

    2016-07-26

    The intracellular serine amidase, fatty acid amide hydrolase (FAAH), degrades a heterogeneous family of lipid-derived bioactive molecules that include amides of long-chain fatty acids with taurine [N-acyl-taurines (NATs)]. The physiological functions of the NATs are unknown. Here we show that genetic or pharmacological disruption of FAAH activity accelerates skin wound healing in mice and stimulates motogenesis of human keratinocytes and differentiation of human fibroblasts in primary cultures. Using untargeted and targeted lipidomics strategies, we identify two long-chain saturated NATs-N-tetracosanoyl-taurine [NAT(24:0)] and N-eicosanoyl-taurine [NAT(20:0)]-as primary substrates for FAAH in mouse skin, and show that the levels of these substances sharply decrease at the margins of a freshly inflicted wound to increase again as healing begins. Additionally, we demonstrate that local administration of synthetic NATs accelerates wound closure in mice and stimulates repair-associated responses in primary cultures of human keratinocytes and fibroblasts, through a mechanism that involves tyrosine phosphorylation of the epidermal growth factor receptor and an increase in intracellular calcium levels, under the permissive control of transient receptor potential vanilloid-1 receptors. The results point to FAAH-regulated NAT signaling as an unprecedented lipid-based mechanism of wound-healing control in mammalian skin, which might be targeted for chronic wound therapy. PMID:27412859

  2. Enzymatic Transesterification of Kraft Lignin with Long Acyl Chains in Ionic Liquids

    Directory of Open Access Journals (Sweden)

    Lise Hulin

    2015-09-01

    Full Text Available Valorization of lignin is essential for the economic viability of the biorefinery concept. For example, the enhancement of lignin hydrophobicity by chemical esterification is known to improve its miscibility in apolar polyolefin matrices, thereby helping the production of bio-based composites. To this end and due to its many reactive hydroxyl groups, lignin is a challenging macromolecular substrate for biocatalyzed esterification in non-conventional media. The present work describes for the first time the lipase-catalyzed transesterification of Kraft lignin in ionic liquids (ILs. Three lipases, three 1-butyl-3-methylimidazolium based ILs and ethyl oleate as long chain acyl donor were selected. Best results were obtained with a hydrophilic/hydrophobic binary IL system (1-butyl-3-methylimidazolium trifluoromethanesulfonate/1-butyl-3-methylimidazolium hexafluoro- phosphate, 1/1 v/v and the immobilized lipase B from Candida antarctica (CALB that afforded a promising transesterification yield (ca. 30%. Similar performances were achieved by using 1-butyl-3-methylimidazolium hexafluorophosphate as a coating agent for CALB rather than as a co-solvent in 1-butyl-3-methylimidazolium trifluoromethane-sulfonate thus limiting the use of hydrophobic IL. Structural characterization of lignin oleate was performed by spectroscopic studies (FTIR and 1H-NMR. The synthesized lignin oleate exhibited interesting thermal and textural properties, different from those of the original Kraft lignin.

  3. Topical Administration of Acylated Homoserine Lactone Improves Epithelialization of Cutaneous Wounds in Hyperglycaemic Rats.

    Directory of Open Access Journals (Sweden)

    Lijuan Huang

    Full Text Available Clinicians often experience delayed epithelialization in diabetic patients, for which a high glucose condition is one of the causes. However, the mechanisms underlying delayed wound closure have not been fully elucidated, and effective treatments to enhance epithelialization in patients with hyperglycaemia have not been established. Here we propose a new reagent, acylated homoserine lactone (AHL, to improve the delayed epithelialization due to the disordered formation of a basement membrane of epidermis in hyperglycaemic rats. Acute hyperglycaemia was induced by streptozotocin injection in this experiment. Full thickness wounds were created on the flanks of hyperglycaemic or control rats. Histochemical and immunohistochemical analyses were performed to identify hyperglycaemia-specific abnormalities in epidermal regeneration by comparison between groups. We then examined the effects of AHL on delayed epithelialization in hyperglycaemic rats. Histological analysis showed the significantly shorter epithelializing tissue (P < 0.05, abnormal structure of basement membrane (fragmentation and immaturity, and hypo- and hyperproliferation of basal keratinocytes in hyperglycaemic rats. Treating the wound with AHL resulted in the decreased abnormalities of basement membrane, normal distribution of proliferating epidermal keratinocytes, and significantly promoted epithelialization (P < 0.05 in hyperglycemic rats, suggesting the improving effects of AHL on abnormal epithelialization due to hyperglycemia.

  4. Abelian Groups

    Energy Technology Data Exchange (ETDEWEB)

    Mishina, A.P.

    1995-10-15

    This fifth survey of reviews on abelian groups comprises papers reviewed in 1985-1992. Just as in the preceding surveys, the issues concerning finite abelian groups, topological groups, ordered groups, group algebras, modules (with rare exceptions), and topics on logic are not considered. The issues on the lattice of subgroups of an abelian group are included in Section 11. In contrast to the fourth survey, this one does not contain Sections 6 (N-high subgroups), 9 (rings with a given additive group), and 10 (valuated groups); since only a few papers treated these topics, the material discussed earlier in Sections 9, and 10 is now included in Section 11 and the material of the former Section 6 will be found in Sections 1, 7, 8, and 11 of this survey. On the other hand, the fifth survey has three new sections devoted to separable groups (a new Sect. 5), Butler groups (a new Sect. 6), and the endormorphism rings and automorphism groups of abelian groups (a new Sect. 9).

  5. Removal of the acyl donor residue allows the use of simple alkyl esters as acyl donors for the dynamic kinetic resolution of secondary alcohols

    NARCIS (Netherlands)

    Verzijl, Gerard K.M.; Vries, Johannes G. de; Broxterman, Quirinus B.

    2005-01-01

    The dynamic kinetic resolution of secondary alcohols using a lipase and a ruthenium catalyst required some improvements to make it suitable for its use in an industrial process. The use of p-chlorophenyl acetate as acyl donor is not desirable in view of the toxicity of the side product. We herein re

  6. Evolution of acyl-ACP-thioesterases and β-ketoacyl-ACP-synthases revealed by protein-protein interactions

    OpenAIRE

    Beld, Joris; Jillian L Blatti; Behnke, Craig; Mendez, Michael; Burkart, Michael D.

    2013-01-01

    The fatty acid synthase (FAS) is a conserved primary metabolic enzyme complex capable of tolerating cross-species engineering of domains for the development of modified and overproduced fatty acids. In eukaryotes, acyl-acyl carrier protein thioesterases (TEs) off-load mature cargo from the acyl carrier protein (ACP), and plants have developed TEs for short/medium-chain fatty acids. We showed that engineering plant TEs into the green microalga Chlamydomonas reinhardtii does not result in the p...

  7. GPS Separator

    CERN Multimedia

    2016-01-01

    Footage of the 70 degree ISOLDE GPS separator magnet MAG70 as well as the switchyard for the Central Mass and GLM (GPS Low Mass) and GHM (GPS High Mass) beamlines in the GPS separator zone. In the GPS20 vacuum sector equipment such as the long GPS scanner 482 / 483 unit, faraday cup FC 490, vacuum valves and wiregrid piston WG210 and WG475 and radiation monitors can also be seen. Also the RILIS laser guidance and trajectory can be seen, the GPS main beamgate switch box and the actual GLM, GHM and Central Beamline beamgates in the beamlines as well as the first electrostatic quadrupoles for the GPS lines. Close up of the GHM deflector plates motor and connections and the inspection glass at the GHM side of the switchyard.

  8. HRS Separator

    CERN Multimedia

    2016-01-01

    Footage of the 90 and 60 degree ISOLDE HRS separator magnets in the HRS separator zone. In the two vacuum sectors HRS20 and HRS30 equipment such as the HRS slits SL240, the HRS faraday cup FC300 and wiregrid WG210 can be spotted. Vacuum valves, turbo pumps, beamlines, quadrupoles, water and compressed air connections, DC and signal cabling can be seen throughout the video. The HRS main and user beamgate in the beamline between MAG90 and MAG60 and its switchboxes as well as all vacuum bellows and flanges are shown. Instrumentation such as the HRS scanner unit 482 / 483, the HRS WG470 wiregrid and slits piston can be seen. The different quadrupoles and supports are shown as well as the RILIS guidance tubes and installation at the magnets and the different radiation monitors.

  9. Protective actions of des-acylated ghrelin on brain injury and blood-brain barrier disruption after stroke in mice.

    Science.gov (United States)

    Ku, Jacqueline M; Taher, Mohammadali; Chin, Kai Yee; Barsby, Tom; Austin, Victoria; Wong, Connie H Y; Andrews, Zane B; Spencer, Sarah J; Miller, Alyson A

    2016-09-01

    The major ghrelin forms, acylated ghrelin and des-acylated ghrelin, are novel gastrointestinal hormones. Moreover, emerging evidence indicates that these peptides may have other functions including neuro- and vaso-protection. Here, we investigated whether post-stroke treatment with acylated ghrelin or des-acylated ghrelin could improve functional and histological endpoints of stroke outcome in mice after transient middle cerebral artery occlusion (tMCAo). We found that des-acylated ghrelin (1 mg/kg) improved neurological and functional performance, reduced infarct and swelling, and decreased apoptosis. In addition, it reduced blood-brain barrier (BBB) disruption in vivo and attenuated the hyper-permeability of mouse cerebral microvascular endothelial cells after oxygen glucose deprivation and reoxygenation (OGD + RO). By contrast, acylated ghrelin (1 mg/kg or 5 mg/kg) had no significant effect on these endpoints of stroke outcome. Next we found that des-acylated ghrelin's vasoprotective actions were associated with increased expression of tight junction proteins (occludin and claudin-5), and decreased cell death. Moreover, it attenuated superoxide production, Nox activity and expression of 3-nitrotyrosine. Collectively, these results demonstrate that post-stroke treatment with des-acylated ghrelin, but not acylated ghrelin, protects against ischaemia/reperfusion-induced brain injury and swelling, and BBB disruption, by reducing oxidative and/or nitrosative damage. PMID:27303049

  10. Component Separations

    OpenAIRE

    Heller, Lior; McNichols, Colton H.; Ramirez, Oscar M.

    2012-01-01

    Component separation is a technique used to provide adequate coverage for midline abdominal wall defects such as a large ventral hernia. This surgical technique is based on subcutaneous lateral dissection, fasciotomy lateral to the rectus abdominis muscle, and dissection on the plane between external and internal oblique muscles with medial advancement of the block that includes the rectus muscle and its fascia. This release allows for medial advancement of the fascia and closure of up to 20-...

  11. Component separations.

    Science.gov (United States)

    Heller, Lior; McNichols, Colton H; Ramirez, Oscar M

    2012-02-01

    Component separation is a technique used to provide adequate coverage for midline abdominal wall defects such as a large ventral hernia. This surgical technique is based on subcutaneous lateral dissection, fasciotomy lateral to the rectus abdominis muscle, and dissection on the plane between external and internal oblique muscles with medial advancement of the block that includes the rectus muscle and its fascia. This release allows for medial advancement of the fascia and closure of up to 20-cm wide defects in the midline area. Since its original description, components separation technique underwent multiple modifications with the ultimate goal to decrease the morbidity associated with the traditional procedure. The extensive subcutaneous lateral dissection had been associated with ischemia of the midline skin edges, wound dehiscence, infection, and seroma. Although the current trend is to proceed with minimally invasive component separation and to reinforce the fascia with mesh, the basic principles of the techniques as described by Ramirez et al in 1990 have not changed over the years. Surgeons who deal with the management of abdominal wall defects are highly encouraged to include this technique in their collection of treatment options. PMID:23372455

  12. Potential of acylated peptides to target the influenza A virus

    Directory of Open Access Journals (Sweden)

    Daniel Lauster

    2015-04-01

    Full Text Available For antiviral drug design, especially in the field of influenza virus research, potent multivalent inhibitors raise high expectations for combating epidemics and pandemics. Among a large variety of covalent and non-covalent scaffold systems for a multivalent display of inhibitors, we created a simple supramolecular platform to enhance the antiviral effect of our recently developed antiviral Peptide B (PeBGF, preventing binding of influenza virus to the host cell. By conjugating the peptide with stearic acid to create a higher-order structure with a multivalent display, we could significantly enhance the inhibitory effect against the serotypes of both human pathogenic influenza virus A/Aichi/2/1968 H3N2, and avian pathogenic A/FPV/Rostock/34 H7N1 in the hemagglutination inhibition assay. Further, the inhibitory potential of stearylated PeBGF (C18-PeBGF was investigated by infection inhibition assays, in which we achieved low micromolar inhibition constants against both viral strains. In addition, we compared C18-PeBGF to other published amphiphilic peptide inhibitors, such as the stearylated sugar receptor mimicking peptide (Matsubara et al. 2010, and the “Entry Blocker” (EB (Jones et al. 2006, with respect to their antiviral activity against infection by Influenza A Virus (IAV H3N2. However, while this strategy seems at a first glance promising, the native situation is quite different from our experimental model settings. First, we found a strong potential of those peptides to form large amyloid-like supramolecular assemblies. Second, in vivo, the large excess of cell surface membranes provides an unspecific target for the stearylated peptides. We show that acylated peptides insert into the lipid phase of such membranes. Eventually, our study reveals serious limitations of this type of self-assembling IAV inhibitors.

  13. Arabidopsis PIZZA has the capacity to acylate brassinosteroids.

    Science.gov (United States)

    Schneider, Katja; Breuer, Christian; Kawamura, Ayako; Jikumaru, Yusuke; Hanada, Atsushi; Fujioka, Shozo; Ichikawa, Takanari; Kondou, Youichi; Matsui, Minami; Kamiya, Yuji; Yamaguchi, Shinjiro; Sugimoto, Keiko

    2012-01-01

    Brassinosteroids (BRs) affect a wide range of developmental processes in plants and compromised production or signalling of BRs causes severe growth defects. To identify new regulators of plant organ growth, we searched the Arabidopsis FOX (Full-length cDNA Over-eXpressor gene) collection for mutants with altered organ size and isolated two overexpression lines that display typical BR deficient dwarf phenotypes. The phenotype of these lines, caused by an overexpression of a putative acyltransferase gene PIZZA (PIZ), was partly rescued by supplying exogenous brassinolide (BL) and castasterone (CS), indicating that endogenous BR levels are rate-limiting for the growth of PIZ overexpression lines. Our transcript analysis further showed that PIZ overexpression leads to an elevated expression of genes involved in BR biosynthesis and a reduced expression of BR inactivating hydroxylases, a transcriptional response typical to low BR levels. Taking the advantage of relatively high endogenous BR accumulation in a mild bri1-301 background, we found that overexpression of PIZ results in moderately reduced levels of BL and CS and a strong reduction of typhasterol (TY) and 6-deoxocastasterone (6-deoxoCS), suggesting a role of PIZ in BR metabolism. We tested a set of potential substrates in vitro for heterologously expressed PIZ and confirmed its acyltransferase activity with BL, CS and TY. The PIZ gene is expressed in various tissues but as reported for other genes involved in BR metabolism, the loss-of-function mutants did not display obvious growth phenotypes under standard growth conditions. Together, our data suggest that PIZ can modify BRs by acylation and that these properties might help modulating endogenous BR levels in Arabidopsis.

  14. Arabidopsis PIZZA has the capacity to acylate brassinosteroids.

    Directory of Open Access Journals (Sweden)

    Katja Schneider

    Full Text Available Brassinosteroids (BRs affect a wide range of developmental processes in plants and compromised production or signalling of BRs causes severe growth defects. To identify new regulators of plant organ growth, we searched the Arabidopsis FOX (Full-length cDNA Over-eXpressor gene collection for mutants with altered organ size and isolated two overexpression lines that display typical BR deficient dwarf phenotypes. The phenotype of these lines, caused by an overexpression of a putative acyltransferase gene PIZZA (PIZ, was partly rescued by supplying exogenous brassinolide (BL and castasterone (CS, indicating that endogenous BR levels are rate-limiting for the growth of PIZ overexpression lines. Our transcript analysis further showed that PIZ overexpression leads to an elevated expression of genes involved in BR biosynthesis and a reduced expression of BR inactivating hydroxylases, a transcriptional response typical to low BR levels. Taking the advantage of relatively high endogenous BR accumulation in a mild bri1-301 background, we found that overexpression of PIZ results in moderately reduced levels of BL and CS and a strong reduction of typhasterol (TY and 6-deoxocastasterone (6-deoxoCS, suggesting a role of PIZ in BR metabolism. We tested a set of potential substrates in vitro for heterologously expressed PIZ and confirmed its acyltransferase activity with BL, CS and TY. The PIZ gene is expressed in various tissues but as reported for other genes involved in BR metabolism, the loss-of-function mutants did not display obvious growth phenotypes under standard growth conditions. Together, our data suggest that PIZ can modify BRs by acylation and that these properties might help modulating endogenous BR levels in Arabidopsis.

  15. Fathering After Marital Separation

    Science.gov (United States)

    Keshet, Harry Finkelstein; Rosenthal, Kristine M.

    1978-01-01

    Deals with experiences of a group of separated or divorced fathers who chose to remain fully involved in the upbringing of their children. As they underwent transition from married parenthood to single fatherhood, these men learned that meeting demands of child care contributed to personal stability and growth. (Author)

  16. The separation of adult separation anxiety disorder.

    Science.gov (United States)

    Baldwin, David S; Gordon, Robert; Abelli, Marianna; Pini, Stefano

    2016-08-01

    The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) categorization of mental disorders places "separation anxiety disorder" within the broad group of anxiety disorders, and its diagnosis no longer rests on establishing an onset during childhood or adolescence. In previous editions of DSM, it was included within the disorders usually first diagnosed in infancy, childhood, or adolescence, with the requirement for an onset of symptoms before the age of 18 years: symptomatic adults could only receive a retrospective diagnosis, based on establishing this early onset. The new position of separation anxiety disorder is based upon the findings of epidemiological studies that revealed the unexpectedly high prevalence of the condition in adults, often in individuals with an onset of symptoms after the teenage years; its prominent place within the DSM-5 group of anxiety disorders should encourage further research into its epidemiology, etiology, and treatment. This review examines the clinical features and boundaries of the condition, and offers guidance on how it can be distinguished from other anxiety disorders and other mental disorders in which "separation anxiety" may be apparent.

  17. The separation of adult separation anxiety disorder.

    Science.gov (United States)

    Baldwin, David S; Gordon, Robert; Abelli, Marianna; Pini, Stefano

    2016-08-01

    The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) categorization of mental disorders places "separation anxiety disorder" within the broad group of anxiety disorders, and its diagnosis no longer rests on establishing an onset during childhood or adolescence. In previous editions of DSM, it was included within the disorders usually first diagnosed in infancy, childhood, or adolescence, with the requirement for an onset of symptoms before the age of 18 years: symptomatic adults could only receive a retrospective diagnosis, based on establishing this early onset. The new position of separation anxiety disorder is based upon the findings of epidemiological studies that revealed the unexpectedly high prevalence of the condition in adults, often in individuals with an onset of symptoms after the teenage years; its prominent place within the DSM-5 group of anxiety disorders should encourage further research into its epidemiology, etiology, and treatment. This review examines the clinical features and boundaries of the condition, and offers guidance on how it can be distinguished from other anxiety disorders and other mental disorders in which "separation anxiety" may be apparent. PMID:27503572

  18. Carbohydrate conformation and lipid condensation in monolayers containing glycosphingolipid Gb3: influence of acyl chain structure.

    Science.gov (United States)

    Watkins, Erik B; Gao, Haifei; Dennison, Andrew J C; Chopin, Nathalie; Struth, Bernd; Arnold, Thomas; Florent, Jean-Claude; Johannes, Ludger

    2014-09-01

    Globotriaosylceramide (Gb3), a glycosphingolipid found in the plasma membrane of animal cells, is the endocytic receptor of the bacterial Shiga toxin. Using x-ray reflectivity (XR) and grazing incidence x-ray diffraction (GIXD), lipid monolayers containing Gb3 were investigated at the air-water interface. XR probed Gb3 carbohydrate conformation normal to the interface, whereas GIXD precisely characterized Gb3's influence on acyl chain in-plane packing and area per molecule (APM). Two phospholipids, 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) and 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine (DPPE), were used to study Gb3 packing in different lipid environments. Furthermore, the impact on monolayer structure of a naturally extracted Gb3 mixture was compared to synthetic Gb3 species with uniquely defined acyl chain structures. XR results showed that lipid environment and Gb3 acyl chain structure impact carbohydrate conformation with greater solvent accessibility observed for smaller phospholipid headgroups and long Gb3 acyl chains. In general, GIXD showed that Gb3 condensed phospholipid packing resulting in smaller APM than predicted by ideal mixing. Gb3's capacity to condense APM was larger for DSPC monolayers and exhibited different dependencies on acyl chain structure depending on the lipid environment. The interplay between Gb3-induced changes in lipid packing and the lipid environment's impact on carbohydrate conformation has broad implications for glycosphingolipid macromolecule recognition and ligand binding.

  19. Topo-optical reactions for the identification of O-acyl sugars in amyloid deposits.

    Science.gov (United States)

    Richter, Susann; Makovitzky, Josef

    2009-01-01

    The aldehyde bisulfite toluidine blue (ABT) reaction with former saponification (KOH-ABT) and periodic acid-borohydride reduction-saponification (PB-KOH-ABT) were applied to sections of human amyloid deposits in the respiratory tract. The saponification-induced increase in ABT-reactivity was confined to the presence of O-acyl sugars associated with the amyloid fibrils. The anisotropic and metachromatic effect in the ABT and KOH-ABT reaction was reduced in the corresponding PB-KOH-ABT reaction, a difference attributed to the removal of staining due to neutral carbohydrate residues. Since the periodic acid-borohydride reduction abolishes all pre-existing ABT-reactivity of neutral sugar vicinal diols, the isolated KOH-effect could be shown using the PB-KOH-ABT reaction. By application of this sequence, the problem identifying small quantities of O-acyl sugars was solved. It is suggested that the KOH-effect depends upon the removal of O-acyl substituents located on the polyhydroxy side chain (C7, C8, C9) of sialic acid residues. An advantage of such topo-optical reactions over biochemical techniques is the exact localization of O-acyl sugars in tissue sites. By means of the KOH-ABT and PB-KOH-ABT reactions we have demonstrated, for the first time, that O-acyl sugars occur within amyloid deposits.

  20. THE EFFECTS OF EXERCISE ON FOOD INTAKE AND HUNGER: RELATIONSHIP WITH ACYLATED GHRELIN AND LEPTIN

    Directory of Open Access Journals (Sweden)

    Serife Vatansever-Ozen

    2011-06-01

    Full Text Available This study investigated the effects of a long bout of aerobic exercise on hunger and energy intake and circulating levels of leptin and acylated ghrelin. Ten healthy male subjects undertook two, 4 h trials in a randomized crossover design. In the exercise trial subjects ran for 105 min at 50% of maximal oxygen uptake and the last 15 min at 70% of maximal oxygen uptake followed by a 120 min rest period. In the control trial, subjects rested for 4 h. Subjects consumed a buffet test meal at 180 min during each trial. Hunger ratings, acylated ghrelin, leptin, glucose and insulin concentrations were measured at 0, 1, 2, 3 and 4 h. No differences were found at baseline values for hunger, acylated ghrelin, leptin, insulin and glucose for both trials (p > 0.05. The estimated energy expenditure of the exercise trial was 1550 ± 136 kcal. Exercise did not change subsequent absolute energy intake, but produced a significant decrease (p < 0.05 in relative energy intake. A two-way ANOVA revealed a significant (p < 0. 05 interaction effect for hunger and acylated ghrelin. In conclusion, this exercise regimen had a positive effect on reducing appetite which is related to reduced acylated ghrelin responses over time. This finding lends support for a role of exercise in weight management

  1. Rice bran extract containing acylated steryl glucoside fraction decreases elevated blood LDL cholesterol level in obese Japanese men.

    Science.gov (United States)

    Ito, Yukihiko; Nakashima, Yuri; Matsuoka, Sayuri

    2015-01-01

    People who frequently consume whole grains show a lower incidence of arteriosclerotic disease than people who consume primarily refined grains. We examined whether or not rice bran extract containing the acylated steryl glucosides (ASG) fraction decreases blood LDL cholesterol levels in obese Japanese men with high blood levels of LDL cholesterol. The study utilized a randomized, double-blind design. A total of 51 subjects were randomly allocated to either a rice bran extract containing ASG fraction (RB-ASG) group or a placebo group. Subjects in the RB-ASG group received 30-50 mg/day of RB-ASG, and the placebo group took 9 capsules/day for 12 weeks. Before and after intake, height, weight, body fat percentage, systolic and diastolic blood pressure were measured, blood was collected, and visceral fat area, subcutaneous fat area, and abdominal circumference were determined based on umbilical computed tomography. Percentage decreases in blood LDL cholesterol, non-HDL cholesterol, LDL/HDL ratio, abdominal circumference and subcutaneous fat area were significantly better in the RB-ASG group than in the placebo group. These findings suggest that RB-ASG fraction may reduce blood LDL cholesterol levels and the risk of arteriosclerosis in obese Japanese men with high LDL cholesterol levels.

  2. Profile of the culturable microbiome capable of producing acyl-homoserine lactone in the tobacco phyllosphere

    Institute of Scientific and Technical Information of China (English)

    Di Lv; Anzhou Ma; Xuanming Tang; Zhihui Bai; Hongyan Qi; Guoqiang Zhuang

    2013-01-01

    Bacterial populations coexisting in the phyllosphere niche have important effects on plant health.Quorum sensing (QS) allows bacteria to communicate via diffusible signal molecules,but QS-dependent behaviors in phyllosphere bacterial populations are poorly understood.We investigate the dense and diverse N-acyl-homoserine lactone (AHL)-producing phyllosphere bacteria living on tobacco leaf surfaces via a culture-dependent method and 16S rRNA gene sequencing.Our results indicated that approximately 7.9%-11.7%of the culturable leaf-associated bacteria have the ability to produce AHL based on the assays using whole-cell biosensors.Sequencing of the 16S rRNA gene assigned the AHL-producing strains to two phylogenetic groups,with Gammaproteobacteria (93%) as the predominant group,followed by Alphaproteobacteria.All of the AHL-producing Alphaproteobacteria were affiliated with the genus Rhizobium,whereas the AHL-producing bacteria belonging to the Gammaproteobacteria mainly fell within the genera Pseudomonas,Acinetobacter,Citrobacter,Enterobacter,Pantoea and Serratia.The bioassays of supernatant extracts revealed that a portion of the strains have a remarkable AHL profile for AHL induction activity using the two different biosensors,and one compound in the active extract of a representative isolate,NTL223,corresponded to 3-oxo-hexanoyl-homoserine lactone.A large population size and diversity of bacteria capable of AHL-driven QS were found to cohabit on leaves,implying that cross-communication based AHL-type QS may be common in the phyllosphere.Furthermore,this study provides a general snapshot of a potential valuable application of AHL-producing bacteria inhabiting leaves for their presumable ecological roles in the phyllosphere.

  3. Magnetic separator

    OpenAIRE

    Křupka, Jiří

    2015-01-01

    Cílem bakalářské práce je návrh konstrukčního řešení magnetického separátoru určeného k separaci drobného průmyslového odpadu. Tato zpráva obsahuje přehled zařízení světových výrobců, která slouží k magnetické separaci ocelového odpadu. Dále pak posouzení variant technických řešení konstrukčních uzlů magnetického separátoru a následný výběr konkrétního řešení. Dle vstupních parametrů jsou vypočteny všechny parametry potřebné ke správnému návrhu stroje. Ve výpočtech jsou zahrnuty i odůvodnění ...

  4. Proghrelin peptides: Desacyl ghrelin is a powerful inhibitor of acylated ghrelin, likely to impair physiological effects of acyl ghrelin but not of obestatin A study of pancreatic polypeptide secretion from mouse islets

    DEFF Research Database (Denmark)

    Kumar, Rajesh; Salehi, Albert; Rehfeld, Jens F;

    2010-01-01

    Proghrelin, produced by the ghrelin (A-like) cells of the gastric mucosa, gives rise to cleavage products, including desacyl ghrelin, acyl ghrelin and obestatin. The products are thought to be secreted concomitantly. In an earlier study we found acyl ghrelin and obestatin, but not desacyl ghrelin......, to suppress the release of hormones from isolated islets of mouse and rat pancreas....

  5. Proghrelin peptides: Desacyl ghrelin is a powerful inhibitor of acylated ghrelin, likely to impair physiological effects of acyl ghrelin but not of obestatin A study of pancreatic polypeptide secretion from mouse islets

    DEFF Research Database (Denmark)

    Kumar, Rajesh; Salehi, Albert; Rehfeld, Jens F;

    2010-01-01

    Proghrelin, produced by the ghrelin (A-like) cells of the gastric mucosa, gives rise to cleavage products, including desacyl ghrelin, acyl ghrelin and obestatin. The products are thought to be secreted concomitantly. In an earlier study we found acyl ghrelin and obestatin, but not desacyl ghrelin...

  6. The mitochondrial acyl carrier protein (ACP) coordinates mitochondrial fatty acid synthesis with iron sulfur cluster biogenesis.

    Science.gov (United States)

    Van Vranken, Jonathan G; Jeong, Mi-Young; Wei, Peng; Chen, Yu-Chan; Gygi, Steven P; Winge, Dennis R; Rutter, Jared

    2016-01-01

    Mitochondrial fatty acid synthesis (FASII) and iron sulfur cluster (FeS) biogenesis are both vital biosynthetic processes within mitochondria. In this study, we demonstrate that the mitochondrial acyl carrier protein (ACP), which has a well-known role in FASII, plays an unexpected and evolutionarily conserved role in FeS biogenesis. ACP is a stable and essential subunit of the eukaryotic FeS biogenesis complex. In the absence of ACP, the complex is destabilized resulting in a profound depletion of FeS throughout the cell. This role of ACP depends upon its covalently bound 4'-phosphopantetheine (4-PP)-conjugated acyl chain to support maximal cysteine desulfurase activity. Thus, it is likely that ACP is not simply an obligate subunit but also exploits the 4-PP-conjugated acyl chain to coordinate mitochondrial fatty acid and FeS biogenesis. PMID:27540631

  7. Long Chain N-acyl Homoserine Lactone Production by Enterobacter sp. Isolated from Human Tongue Surfaces

    Directory of Open Access Journals (Sweden)

    Kok-Gan Chan

    2012-10-01

    Full Text Available We report the isolation of N-acyl homoserine lactone-producing Enterobacter sp. isolate T1-1 from the posterior dorsal surfaces of the tongue of a healthy individual. Spent supernatants extract from Enterobacter sp. isolate T1-1 activated the biosensor Agrobacterium tumefaciens NTL4(pZLR4, suggesting production of long chain AHLs by these isolates. High resolution mass spectrometry analysis of these extracts confirmed that Enterobacter sp. isolate T1-1 produced a long chain N-acyl homoserine lactone, namely N-dodecanoyl-homoserine lactone (C12-HSL. To the best of our knowledge, this is the first isolation of Enterobacter sp., strain T1-1 from the posterior dorsal surface of the human tongue and N-acyl homoserine lactones production by this bacterium.

  8. Systems Analysis of Protein Fatty Acylation in Herpes Simplex Virus-Infected Cells Using Chemical Proteomics

    Science.gov (United States)

    Serwa, Remigiusz A.; Abaitua, Fernando; Krause, Eberhard; Tate, Edward W.; O’Hare, Peter

    2015-01-01

    Summary Protein fatty acylation regulates diverse aspects of cellular function and organization and plays a key role in host immune responses to infection. Acylation also modulates the function and localization of virus-encoded proteins. Here, we employ chemical proteomics tools, bio-orthogonal probes, and capture reagents to study myristoylation and palmitoylation during infection with herpes simplex virus (HSV). Using in-gel fluorescence imaging and quantitative mass spectrometry, we demonstrate a generalized reduction in myristoylation of host proteins, whereas palmitoylation of host proteins, including regulators of interferon and tetraspanin family proteins, was selectively repressed. Furthermore, we found that a significant fraction of the viral proteome undergoes palmitoylation; we identified a number of virus membrane glycoproteins, structural proteins, and kinases. Taken together, our results provide broad oversight of protein acylation during HSV infection, a roadmap for similar analysis in other systems, and a resource with which to pursue specific analysis of systems and functions. PMID:26256475

  9. Relationships Between Serum Interleukn-18 Concentration with Acylated Ghrelin, Growth Hormone, Insulin Resistance, and Lipid Profile in Obese and Lean Men

    Directory of Open Access Journals (Sweden)

    F Moradi

    2015-02-01

    Conclusions: The study findings revealed that in both groups of obese and lean men, serum levels of IL-18 positively correlated with insulin resistance and triglyceride, and negatively correlated with high-density lipoprotein. Furthermore, within obese individuals that have elevated IL-18 levels, this can be associated with disorder in glycemic control and lipid profile, and thus, with increased risk of cardiovascular and metabolic disorders. IL-18 levels do not appear to have any correlations with acylated ghrelin, growth hormone, total cholesterol, and low-density lipoprotein.

  10. Acyl lipidation of a peptide: effects on activity and epidermal permeability in vitro

    Science.gov (United States)

    Rocco, Daniel; Ross, James; Murray, Paul E; Caccetta, Rima

    2016-01-01

    Short-chain lipid conjugates can increase permeability of a small peptide across human epidermis; however, the emerging lipoaminoacid (LAA) conjugation technique is costly and can deliver mixed synthetic products of varied biological potential. LAA conjugation using a racemic mixture produces a mixture of D- and L-stereoisomers. Individual enantiomers can be produced at an extra cost. We investigated an affordable technique that produces only one synthetic product: short-chain (C7–C8) acyl lipidation. Acyl lipidation of Ala-Ala-Pro-Val, an inhibitor of human neutrophil elastase (HNE; believed to lead to abnormal tissue destruction and disease development), was investigated as an alternative to LAA conjugation. The current study aimed to assess the effects of acyl lipidation (either at the N-terminal or at the C-terminal) on neutrophil elastase activity in vitro and on transdermal delivery ex vivo. The inhibitory capacity of the acyl conjugates was compared to LAA conjugates (conjugated at the N-terminal) of the same peptide. The L-stereoisomer appears to rapidly degrade, but it represents a significantly (P<0.05) better inhibitor of HNE than the parent peptide (Ala-Ala-Pro-Val). Although the D-stereoisomer appears to permeate human epidermal skin sections in a better fashion than the L-stereoisomer, it is not a significantly better inhibitor of HNE than the parent peptide. Acyl lipidation (with a C7 lipid chain) at either end of the peptide substantially enhances the permeability of the peptide across human skin epidermis as well as significantly (P<0.005) increases its elastase inhibitory potential. Therefore, our current study indicates that acyl lipidation of a peptide is a more economical and effective alternative to LAA conjugation. PMID:27468224

  11. Kinetics of acyl transfer reactions in organic media catalysed by Candida antarctica lipase B.

    Science.gov (United States)

    Martinelle, M; Hult, K

    1995-09-01

    The acyl transfer reactions catalysed by Candida antartica lipase B in organic media followed a bi-bi ping-pong mechanism, with competitive substrate inhibition by the alcohols used as acyl acceptors. The effect of organic solvents on Vm and Km was investigated. The Vm values in acetonitrile was 40-50% of those in heptane. High Km values in acetonitrile compared to those in heptane could partly be explained by an increased solvation of the substrates in acetonitrile. Substrate solvation caused a 10-fold change in substrate specificity, defined as (Vm/Km)ethyl octanoate/(Vm/Km)octanoic acid, going from heptane to acetonitrile. Deacylation was the rate determining step for the acyl transfer in heptane with vinyl- and ethyl octanoate as acyl donors and (R)-2-octanol as acyl acceptor. With 1-octanol, a rate determining deacylation step in heptane was indicated using the same acyl donors. Using 1-octanol as acceptor in heptane, S-ethyl thiooctanoate had a 25- to 30-fold lower Vm/Km value and vinyl octanoate a 4-fold higher Vm/Km value than that for ethyl octanoate. The difference showed to be a Km effect for vinyl octanoate and mainly a Km effect for S-ethyl thiooctanoate. The Vm values of the esterification of octanoic acid with different alcohols was 10-30-times lower than those for the corresponding transesterification of ethyl octanoate. The low activity could be explained by a low pH around the enzyme caused by the acid or a withdrawing of active enzyme by nonproductive binding by the acid.

  12. An Efficient Method for the Synthesis of Acyl-diazenes Using NaNO2/NaHSO4·H2O

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    An efficient and convenient method for the synthesis of acyl-diazenes is reported. Ten acyl-diazenes have been synthesized from acylhydrazines in excellent yields under mild conditions. There are eight new substances among these compounds.

  13. Expression of acyl-CoA synthetase 5 reflects the state of villus architecture in human small intestine

    DEFF Research Database (Denmark)

    Gassler, Nikolaus; Kopitz, Jürgen; Tehrani, Arman;

    2004-01-01

    . Screening of antibodies from a hybridoma library led to the identification of an acyl-CoA synthetase 5-specific monoclonal antibody. Protein synthesis, mRNA expression, and the enzyme activity of acyl-CoA synthetase 5 were studied by several methods in human small intestinal tissues with Crohn's disease...

  14. Affinity of 3-acyl substituted 4-quinolones at the benzodiazepine site of GABAA receptors

    DEFF Research Database (Denmark)

    Lager, Erik; Nilsson, Jakob; Nielsen, Elsebet Østergaard;

    2008-01-01

    The finding that alkyl 1,4-dihydro-4-oxoquinoline-3-carboxylate and N-alkyl-1,4-dihydro-4-oxoquinoline-3-carboxamide derivatives may be high-affinity ligands at the benzodiazepine binding site of the GABA(A) receptor, prompted a study of 3-acyl-1,4-dihydro-4-oxoquinoline (3-acyl-4-quinolones). In...

  15. Long-chain acyl-CoA-dependent regulation of gene expression in bacteria, yeast and mammals

    DEFF Research Database (Denmark)

    Black, P N; Færgeman, Nils J.; DiRusso, C C

    2000-01-01

    Fatty acyl-CoA thioesters are essential intermediates in lipid metabolism. For many years there have been numerous conflicting reports concerning the possibility that these compounds also serve regulatory functions. In this review, we examine the evidence that long-chain acyl-CoA is a regulatory ...

  16. Production of specific-structured lipids by enzymatic interesterification: elucidation of acyl migration by response surface design

    DEFF Research Database (Denmark)

    Xu, Xuebing; Skands, Anja; Høy, Carl-Erik;

    1998-01-01

    Production of specific-structured lipids (SSL) by lipase-catalyzed interesterification has been attracting more and more attention recently. However, it was found that acyl migration occurs during the reaction and causes the production of by-products. In this paper, the elucidation of acyl migrat...

  17. Continuous recording of long-chain acyl-coenzyme A synthetase activity using fluorescently labeled bovine serum albumin

    DEFF Research Database (Denmark)

    Demant, Erland J.F.; Nystrøm, Birthe T.

    2001-01-01

    acyl-Coenzyme A, synthetase, activity assay, fluorescence recording, fatty acid probe, serum albumin, hydroxycoumarin, detergent, micelles, Pseudomonas fragi, rat liver microsomes......acyl-Coenzyme A, synthetase, activity assay, fluorescence recording, fatty acid probe, serum albumin, hydroxycoumarin, detergent, micelles, Pseudomonas fragi, rat liver microsomes...

  18. Acylation, Diastereoselective Alkylation, and Cleavage of an Oxazolidinone Chiral Auxiliary: A Multistep Asymmetric Synthesis Experiment for Advanced Undergraduates

    Science.gov (United States)

    Smith, Thomas E.; Richardson, David P.; Truran, George A.; Belecki, Katherine; Onishi, Megumi

    2008-01-01

    An introduction to the concepts and experimental techniques of diastereoselective synthesis using a chiral auxiliary is described. The 4-benzyl-2-oxazolidinone chiral auxiliary developed by Evans is acylated with propionic anhydride under mild conditions using DMAP as an acyl transfer catalyst. Deprotonation with NaN(TMS)[subscript 2] at -78…

  19. Purification of specific structured lipids by distillation: Effects on acyl migration

    DEFF Research Database (Denmark)

    Xu, Xuebing; Skands, A.; Adler-Nissen, Jens

    2001-01-01

    contained a large amount of free fatty acids and a small amount of partial acylglycerols besides triacylglycerols. Therefore, the effect of steam, free fatty acids, diacylglycerols, and monoacylglycerols on acyl migration was studied in a palm oil midfraction model. The results showed that all these factors......The cause and effects of acyl migration during the purification of specific structured lipids by distillation were studied in a conventional batch deodorizer with stripping steam. The mixture of specific structured lipids produced by lipase-catalyzed acidolysis between rapeseed oil and capric acid...

  20. Macrocyclic prolinyl acyl guanidines as inhibitors of β-secretase (BACE).

    Science.gov (United States)

    Boy, Kenneth M; Guernon, Jason M; Wu, Yong-Jin; Zhang, Yunhui; Shi, Joe; Zhai, Weixu; Zhu, Shirong; Gerritz, Samuel W; Toyn, Jeremy H; Meredith, Jere E; Barten, Donna M; Burton, Catherine R; Albright, Charles F; Good, Andrew C; Grace, James E; Lentz, Kimberley A; Olson, Richard E; Macor, John E; Thompson, Lorin A

    2015-11-15

    The synthesis, evaluation, and structure-activity relationships of a class of acyl guanidines which inhibit the BACE-1 enzyme are presented. The prolinyl acyl guanidine chemotype (7c), unlike compounds of the parent isothiazole chemotype (1), yielded compounds with good agreement between their enzymatic and cellular potency as well as a reduced susceptibility to P-gp efflux. Further improvements in potency and P-gp ratio were realized via a macrocyclization strategy. The in vivo profile in wild-type mice and P-gp effects for the macrocyclic analog 21c is presented.

  1. Synthesis and Biological Activity Evaluation of Schiff Bases of 5-Acyl-1,2,4-Triazine

    International Nuclear Information System (INIS)

    A simple and general method has been developed for the synthesis of various Schiff bases (oximes, hydrazones, semicarbazones and thiosemicarbazones) derived from 5-acyl-1,2,4-triazines. Some of the new synthesized Schiff bases were tested for biological activity but only oximes 2a-c shown poor antiviral activity. The oxime derivatives of 5-acyl-3-methylsulfanyl-1,2,4-triazine were tested with pea-seedling diamine oxidase as the enzyme is known to be inhibited by oxime compounds. However, only weak non-competitive inhibitory effects were observed (Ki of 10 /sup -2/ M). (author)

  2. Thermodynamically based solvent design for enzymatic saccharide acylation with hydroxycinnamic acids in non-conventional media.

    Science.gov (United States)

    Zeuner, Birgitte; Kontogeorgis, Georgios M; Riisager, Anders; Meyer, Anne S

    2012-02-15

    Enzyme-catalyzed synthesis has been widely studied with lipases (EC 3.1.1.3), but feruloyl esterases (FAEs; EC 3.1.1.73) may provide advantages such as higher substrate affinity and regioselectivity in the synthesis of hydroxycinnamate saccharide esters. These compounds are interesting because of their amphiphilicity and antioxidative potential. Synthetic reactions using mono- or disaccharides as one of the substrates may moreover direct new routes for biomass upgrading in the biorefinery. The paper reviews the available data for enzymatic hydroxycinnamate saccharide ester synthesis in organic solvent systems as well as other enzymatic hydroxycinnamate acylations in ionic liquid systems. The choice of solvent system is highly decisive for enzyme stability, selectivity, and reaction yields in these synthesis reactions. To increase the understanding of the reaction environment and to facilitate solvent screening as a crucial part of the reaction design, the review explores the use of activity coefficient models for describing these systems and - more importantly - the use of group contribution model UNIFAC and quantum chemistry based COSMO-RS for thermodynamic predictions and preliminary solvent screening. Surfactant-free microemulsions of a hydrocarbon, a polar alcohol, and water are interesting solvent systems because they accommodate different substrate and product solubilities and maintain enzyme stability. Ionic liquids may provide advantages as solvents in terms of increased substrate and product solubility, higher reactivity and selectivity, as well as tunable physicochemical properties, but their design should be carefully considered in relation to enzyme stability. The treatise shows that thermodynamic modeling tools for solvent design provide a new toolbox to design enzyme-catalyzed synthetic reactions from biomass sources. PMID:22154740

  3. 40 CFR 721.10055 - 1-Propanaminium, 3-amino-N-(carboxymethyl)-N,N-dimethyl-, N-soya acyl derivs., inner salts.

    Science.gov (United States)

    2010-07-01

    ...-(carboxymethyl)-N,N-dimethyl-, N-soya acyl derivs., inner salts. 721.10055 Section 721.10055 Protection of...-amino-N-(carboxymethyl)-N,N-dimethyl-, N-soya acyl derivs., inner salts. (a) Chemical substance and...-(carboxymethyl)-N,N-dimethyl-, N-soya acyl derivs., inner salts (PMN P-03-46; CAS No. 136504-87-5) is subject...

  4. 40 CFR 721.10193 - 1-Butanaminium, N-(3-aminopropyl)-N-butyl-N-(2-carboxyethyl)-, N-coco acyl derivs., inner salts.

    Science.gov (United States)

    2010-07-01

    ...-butyl-N-(2-carboxyethyl)-, N-coco acyl derivs., inner salts. 721.10193 Section 721.10193 Protection of...-aminopropyl)-N-butyl-N-(2-carboxyethyl)-, N-coco acyl derivs., inner salts. (a) Chemical substance and...-aminopropyl)-N-butyl-N-(2-carboxyethyl)-, N-coco acyl derivs., inner salts (PMN P-06-263, Chemical B; CAS...

  5. Iron-Catalyzed Acylation of Polyfunctionalized Aryl- and Benzylzinc Halides with Acid Chlorides.

    Science.gov (United States)

    Benischke, Andreas D; Leroux, Marcel; Knoll, Irina; Knochel, Paul

    2016-08-01

    FeCl2 (5 mol %) catalyzes a smooth and convenient acylation of functionalized arylzinc halides at 50 °C (2-4 h) and benzylic zinc chlorides at 25 °C (0.5-4 h) with a variety of acid chlorides leading to polyfunctionalized diaryl and aryl heteroaryl ketones. PMID:27457108

  6. NMR structure of an acyl-carrier protein from Borrelia burgdorferi

    International Nuclear Information System (INIS)

    The high-resolution NMR structure of the acyl-carrier protein from the pathogen B. burgdorferi determined to a r.m.s. deviation of 0.4 Å over the protein backbone is reported. The NMR structure was determined using multidimensional NMR spectroscopy and consists of four α-helices and two 310-helices. Structural comparison reveals that this protein is highly similar to the acyl-carrier protein from A. aeolicus. Nearly complete resonance assignment and the high-resolution NMR structure of the acyl-carrier protein from Borrelia burgdorferi, a target of the Seattle Structural Genomics Center for Infectious Disease (SSGCID) structure-determination pipeline, are reported. This protein was chosen as a potential target for drug-discovery efforts because of its involvement in fatty-acid biosynthesis, an essential metabolic pathway, in bacteria. It was possible to assign >98% of backbone resonances and >92% of side-chain resonances using multidimensional NMR spectroscopy. The NMR structure was determined to a backbone r.m.s.d. of 0.4 Å and contained four α-helices and two 310-helices. A structure-homology search revealed that this protein is highly similar to the acyl-carrier protein from Aquifex aeolicus

  7. Mutations in the medium chain acyl-CoA dehydrogenase (MCAD) gene

    DEFF Research Database (Denmark)

    Tanaka, K; Yokota, I; Coates, P M;

    1992-01-01

    Medium chain acyl-CoA dehydrogenase (MCAD) catalyzes the first reaction of the beta-oxidation cycle for 4-10-carbon fatty acids. MCAD deficiency is one of the most frequent inborn metabolic disorders in populations of northwestern European origin. In the compilation of data from a worldwide study...

  8. Acyl migration kinetics of 2-monoacylglycerols from soybean oil via 1 hour Nuclear Magnetic Resonance (NMR)

    Science.gov (United States)

    The acyl migration kinetics of neat 2-monoacylglycerol (2-MAG) to form 1-monoacylglycerol (1-MAG) was determined using proton NMR spectroscopy to monitor the beta-proton integration ratios of the two species over time. 2-MAG was synthesized by the Novozym 435-catalyzed alcoholysis of soybean oil an...

  9. Liver fatty acid binding protein (LFABP) transfers fatty acids and fatty acyl coas to membranes

    OpenAIRE

    De Gerónimo, Eduardo; Hagan, Robert M; Wilton, David C.; Córsico, Betina

    2010-01-01

    The objective of this work was to analyze LFABP´s capacity to transfer acyl CoAs to artificial membranes and compare it to LCFA transfer employing natural ligands, in order to better understand the specific physiological role of LFABP in the cell.

  10. Quorum quenching by an N-acyl-homoserine lactone acylase from Pseudomonas aeruginosa PAO1

    NARCIS (Netherlands)

    Sio, CF; Otten, LG; Cool, RH; Diggle, SP; Braun, PG; Daykin, M; Camara, M; Williams, P; Quax, WJ; Bos, R

    2006-01-01

    The virulence of the opportunistic human pathogen Pseudomonas aeruginosa PAO1 is controlled by an N-acyl-homoserine lactone (AHL)-dependent quorum-sensing system. During functional analysis of putative acylase genes in the P. aeruginosa PAO1 genome, the PA2385 gene was found to encode an acylase tha

  11. Acyl Radicals from Aromatic Carboxylic Acids by Means of Visible-Light Photoredox Catalysis

    OpenAIRE

    Bergonzini, Giulia; Cassani, Carlo; Wallentin, Carl-Johan

    2015-01-01

    Simple and abundant carboxylic acids have been used as acyl radical precursor by means of visible-light photoredox catalysis. By the transient generation of a reactive anhydride intermediate, this redox-neutral approach offers a mild and rapid entry to high-value heterocyclic compounds without the need of UV irradiation, high temperature, high CO pressure, tin reagents, or peroxides.

  12. Influence of fatty acid desaturation on spontaneous acyl migration in 2-monoacylglycerols

    Science.gov (United States)

    The effect of desaturation from the C9 to the C15 carbon of 2-monoacylglycerol (2-MAG) fatty acids on spontaneous acyl migration is described. Density functional calculations for 2-monooleoylglycerol (C18:cis-delta9), 2-monolinoleoylglycerol (C18:cis-delta9,12), and 2-monolinolenoylglycerol (C18:cis...

  13. TFFH as an excellent reagent for acylation of alcohols, thiols and dithiocarbamates

    DEFF Research Database (Denmark)

    Pittelkow, M.; Kamounah, F. S.; Boas, Ulrik;

    2004-01-01

    A convenient and easy procedure to synthesize esters and thioesters from the corresponding carboxylic acid using TFFH as the coupling reagent is described. The preparation of N-acyl-dithiocarbamates from carboxylic acids and 1,3-thiazolidine-2-thione with TFFH as the coupling reagent is also...

  14. Different effects of ghrelin, des-acyl ghrelin and obestatin on gastroduodenal motility in conscious rats

    Institute of Scientific and Technical Information of China (English)

    Mineko Fujimiya; Aldhiro Asakawa; Koji Ataka; Ikuo Kato; Akio Inui

    2008-01-01

    Three peptides, ghrelin, des-acyl ghrelin and obestatin are derived from a common prohormone, preproghre-lin by posttranslational processing, originating from endocrine cells in the stomach. To examine the effects of these peptides, we applied the manometric mea-surement of gastrointestinal motility in freely moving conscious rat models. Ghrelin exerts stimulatory ef-fects on the motility of antrum and duodenum in both fed and fasted state of animals. Des-acyl ghrelin exerts inhibitory effects on the motility of antrum, but not on the motility of duodenum in the fasted state of ani-mals. Obestatin exerts inhibitory effects on the motility of antrum and duodenum in the fed state, but not in the fasted state of animals. NPY Y2 or Y4 receptors in the brain may mediate the action of ghrelin, CRF type 2 receptors in the brain mediate the action of des-acyl ghrelin, whereas CRF type 1 and type 2 receptors in the brain mediate the action of obestatin. Vagal affer-ent pathways might be involved in the action of ghre-lin, but not involved in the action of des-acyl ghrelin, whereas vagal afferent pathways might be partially involved in the action of obestatin.

  15. Isolation and Purification of a Novel Long-chain Acyl Catechin from Lipophilic Tea Polyphenols

    Institute of Scientific and Technical Information of China (English)

    陈平; 杜琪珍

    2003-01-01

    Llpophilic tea polyphenols (LTP) was prepared by esterification of green tea polyphenols (GTP) with hexadecanoyl chloride. A novel long-chaln acyl catechin was isolated and purified from LTP by high-speed countercurrent chromatography (HSCCC).Its molecular structure was elucidated as epigallocatechin-3-O-gallate-4'-O-hexadecanate by elemental analysis, IR, MS and 1H NMR spectra.

  16. An insight on acyl migration in solvent-free ethanolysis of model triglycerides using Novozym 435.

    Science.gov (United States)

    Sánchez, Daniel Alberto; Tonetto, Gabriela Marta; Ferreira, María Luján

    2016-02-20

    In this work, the ethanolysis of triglycerides catalyzed by immobilized lipase was studied, focusing on the secondary reaction of acyl migration. The catalytic tests were performed in a solvent-free reaction medium using Novozym 435 as biocatalyst. The selected experimental variables were biocatalyst loading (5-20mg), reaction time (30-90min), and chain length of the fatty acids in triglycerides with and without unsaturation (short (triacetin), medium (tricaprylin) and long (tripalmitin/triolein)). The formation of 2-monoglyceride by ethanolysis of triglycerides was favored by long reaction times and large biocatalyst loading with saturated short- to medium-chain triglycerides. In the case of long-chain triglycerides, the formation of this monoglyceride was widely limited by acyl migration. In turn, acyl migration increased the yield of ethyl esters and minimized the content of monoglycerides and diglycerides. Thus, the enzymatic synthesis of biodiesel was favored by long-chain triglycerides (which favor the acyl migration), long reaction times and large biocatalyst loading. The conversion of acylglycerides made from long-chain fatty acids with unsaturation was relatively low due to limitations in their access to the active site of the lipase. PMID:26795690

  17. Synthesis of new 3- and 4-substituted analogues of acyl homoserine lactone quorum sensing autoinducers

    DEFF Research Database (Denmark)

    Olsen, J. A.; Severinsen, R.; Rasmussen, T. B.;

    2002-01-01

    The quorum sensing mechanism in Gram-negative bacteria uses small intercellular signal molecules, N-acyl-homoserine lactones (AHLs), to control transcription of specific genes in relation to population density. In this communication, we describe the parallel synthesis of new AHL analogues, in whi...

  18. In vitro and in vivo aspects of N-acyl-phosphatidylethanolamine-containing liposomes

    DEFF Research Database (Denmark)

    Vermehren, C.; Clausen-Beck, B.; Frøkjær, S.;

    2003-01-01

    Incorporation of the phospholipid, N-acyl-phosphatidylethanolamine (NAPE), has shown to increase the liposomal stability towards plasma components in vitro. Besides increasing the circulation-time, NAPE has been shown to contain fusiogenic properties. Hence, fusion between NAPE-liposomes and targ...

  19. The acyl-CoA binding protein is required for normal epidermal barrier function in mice

    DEFF Research Database (Denmark)

    Bloksgaard, Maria; Bek, Signe; Marcher, Ann-Britt;

    2012-01-01

    The acyl-CoA binding protein (ACBP) is a 10 kDa intracellular protein expressed in all eukaryotic species. Mice with targeted disruption of Acbp (ACBP(-/-) mice) are viable and fertile but present a visible skin and fur phenotype characterized by greasy fur and development of alopecia and scaling...

  20. Identification and Assessment of Octreotide Acylation in Polyester Microspheres by LC-MS/MS

    NARCIS (Netherlands)

    Shirangi, Mehrnoosh; Hennink, Wim E.; Somsen, Govert W.; Van Nostrum, Cornelus F.

    2015-01-01

    Purpose: Polyesters with hydrophilic domains, i.e., poly(d,l-lactic-co-glycolic-co-hydroxymethyl glycolic acid) (PLGHMGA) and a multiblock copolymer of poly(ε-caprolactone)-PEG-poly(ε-caprolactone) and poly(l-lactide) ((PC-PEG-PC)-(PL)) are expected to cause less acylation of encapsulated peptides t

  1. REGIOSPECIFIC ANALYSIS OF DIRICINOLEOYL-ACYL-GLYCEROL IN CASTOR OIL USING ELECTROSPRAY IONIZATION-MASS SPECTROMETRY

    Science.gov (United States)

    HPLC fractions of castor oil were used to identify the regiospecific location of non-hydroxyl fatty acids on glycerol backbone in diricinoleoyl-acyl-glycerols using electrospray ionization MS3 of lithium adducts. The regiospecific ions in MS3 spectra were from the loss of 'a,B'-unsaturated fatty aci...

  2. Adult peroxisomal acyl-coenzyme A oxidase deficiency with cerebellar and brainstem atrophy

    NARCIS (Netherlands)

    S. Ferdinandusse; S. Barker; K. Lachlan; M. Duran; H.R. Waterham; R.J.A. Wanders; S. Hammans

    2010-01-01

    Peroxisomal acyl-coenzyme A oxidase deficiency ( formerly also called pseudoneonatal adrenoleucodystrophy) is a disorder of peroxisomal fatty acid oxidation with a severe presentation. Most patients present at birth or in early infancy, and the mean age of death was 5 years in a recently published c

  3. Medium chain acyl-CoA dehydrogenase deficiency and fatal valproate toxicity

    NARCIS (Netherlands)

    Njolstad, PR; Skjeldal, OH; Agsteribbe, E; Huckriede, A; Wannag, E; Sovik, O; Waaler, PE

    1997-01-01

    A boy with delayed psychomotor development, attention deficit disorder, and therapy-resistant epilepsy was treated with valproate. The patient died of liver failure after 4 months of valproate treatment. Postmortem investigation of cultured fibroblasts suggested medium chain acyl-CoA dehydrogenase d

  4. Proton NMR: a convenient method for determining 2-monoacylglycerol acyl migration

    Science.gov (United States)

    The acyl migration kinetics of neat (not exposed to solvent) 2-monoacylglycerol (2-MAG) to form 1-monoacylglycerol (1-MAG) was determined using proton NMR spectroscopy to monitor the B-proton integration ratios of the two species over time. 2-MAG was synthesized by the Novozym 435-catalyzed alcohol...

  5. Cortical dynamics of figure-ground separation in response to 2D pictures and 3D scenes:How V2 combines border ownership, stereoscopic cues, and Gestalt grouping rules

    Directory of Open Access Journals (Sweden)

    Stephen eGrossberg

    2016-01-01

    Full Text Available The FACADE model, and its laminar cortical realization and extension in the 3D LAMINART model, have explained, simulated, and predicted many perceptual and neurobiological data about how the visual cortex carries out 3D vision and figure-ground perception, and how these cortical mechanisms enable 2D pictures to generate 3D percepts of occluding and occluded objects. In particular, these models have proposed how border ownership occurs, but have not yet explicitly explained the correlation between multiple properties of border ownership neurons in cortical area V2 that were reported in a remarkable series of neurophysiological experiments by von der Heydt and his colleagues; namely, border ownership, contrast preference, binocular stereoscopic information, selectivity for side-of-figure, Gestalt rules, and strength of attentional modulation, as well as the time course during which such properties arise. This article shows how, by combining 3D LAMINART properties that were discovered in two parallel streams of research, a unified explanation of these properties emerges. This explanation proposes, moreover, how these properties contribute to the generation of consciously seen 3D surfaces. The first research stream models how processes like 3D boundary grouping and surface filling-in interact in multiple stages within and between the V1 interblob – V2 interstripe – V4 cortical stream and the V1 blob – V2 thin stripe – V4 cortical stream, respectively. Of particular importance for understanding figure-ground separation is how these cortical interactions convert computationally complementary boundary and surface mechanisms into a consistent conscious percept, including the critical use of surface contour feedback signals from surface representations in V2 thin stripes to boundary representations in V2 interstripes. Remarkably, key figure-ground properties emerge from these feedback interactions. The second research stream shows how cells that

  6. Localization of fatty acyl and double bond positions in phosphatidylcholines using a dual stage CID fragmentation coupled with ion mobility mass spectrometry.

    Science.gov (United States)

    Castro-Perez, Jose; Roddy, Thomas P; Nibbering, Nico M M; Shah, Vinit; McLaren, David G; Previs, Stephen; Attygalle, Athula B; Herath, Kithsiri; Chen, Zhu; Wang, Sheng-Ping; Mitnaul, Lyndon; Hubbard, Brian K; Vreeken, Rob J; Johns, Douglas G; Hankemeier, Thomas

    2011-09-01

    A high content molecular fragmentation for the analysis of phosphatidylcholines (PC) was achieved utilizing a two-stage [trap (first generation fragmentation) and transfer (second generation fragmentation)] collision-induced dissociation (CID) in combination with travelling-wave ion mobility spectrometry (TWIMS). The novel aspects of this work reside in the fact that a TWIMS arrangement was used to obtain a high level structural information including location of fatty acyl substituents and double bonds for PCs in plasma, and the presence of alkali metal adduct ions such as [M + Li](+) was not required to obtain double bond positions. Elemental compositions for fragment ions were confirmed by accurate mass measurements. A very specific first generation fragment ion m/z 577 (M-phosphoryl choline) from the PC [16:0/18:1 (9Z)] was produced, which by further CID generated acylium ions containing either the fatty acyl 16:0 (C(15)H(31)CO(+), m/z 239) or 18:1 (9Z) (C(17)H(33)CO(+), m/z 265) substituent. Subsequent water loss from these acylium ions was key in producing hydrocarbon fragment ions mainly from the α-proximal position of the carbonyl group such as the hydrocarbon ion m/z 67 (+H(2)C-HC = CH-CH = CH(2)). Formation of these ions was of important significance for determining double bonds in the fatty acyl chains. In addition to this, and with the aid of (13)C labeled lyso-phosphatidylcholine (LPC) 18:1 (9Z) in the ω-position (methyl) TAP fragmentation produced the ion at m/z 57. And was proven to be derived from the α-proximal (carboxylate) or distant ω-position (methyl) in the LPC.

  7. An orphan esterase ABHD10 modulates probenecid acyl glucuronidation in human liver.

    Science.gov (United States)

    Ito, Yusuke; Fukami, Tatsuki; Yokoi, Tsuyoshi; Nakajima, Miki

    2014-12-01

    Probenecid, a widely used uricosuric agent, is mainly metabolized to probenecid acyl glucuronide (PRAG), which is considered a causal substance of severe allergic or anaphylactoid reactions. PRAG can be hydrolyzed (deglucuronidated) to probenecid. The purpose of this study was to identify enzymes responsible for probenecid acyl glucuronidation and PRAG deglucuronidation in human livers and to examine the effect of deglucuronidation in PRAG formation. In human liver homogenates (HLHs), the intrinsic clearance (CLint) of PRAG deglucuronidation was much greater (497-fold) than that of probenecid acyl glucuronidation. Evaluation of PRAG formation by recombinant UDP-glucuronosyltransferase (UGT) isoforms and an inhibition study using HLHs as an enzyme source demonstrated that multiple UGT isoforms, including UGT1A1, UGT1A9, and UGT2B7, catalyzed probenecid acyl glucuronidation. We found that recombinant α/β hydrolase domain containing 10 (ABHD10) substantially catalyzed PRAG deglucuronidation activity, whereas carboxylesterases did not. Similar inhibitory patterns by chemicals between HLHs and recombinant ABHD10 supported the major contribution of ABHD10 to PRAG deglucuronidation in human liver. Interestingly, it was demonstrated that the CLint value of probenecid acyl glucuronidation in HLHs was increased by 1.7-fold in the presence of phenylmethylsulfonyl fluoride, which potently inhibited ABHD10 activity. In conclusion, we found that PRAG deglucuronidation catalyzed by ABHD10 suppressively regulates PRAG formation via multiple UGT enzymes in human liver. The balance of activities by these enzymes is important for the formation of PRAG, which may be associated with the adverse reactions observed after probenecid administration. PMID:25217485

  8. Acyl lipidation of a peptide: effects on activity and epidermal permeability in vitro.

    Science.gov (United States)

    Rocco, Daniel; Ross, James; Murray, Paul E; Caccetta, Rima

    2016-01-01

    Short-chain lipid conjugates can increase permeability of a small peptide across human epidermis; however, the emerging lipoaminoacid (LAA) conjugation technique is costly and can deliver mixed synthetic products of varied biological potential. LAA conjugation using a racemic mixture produces a mixture of D- and L-stereoisomers. Individual enantiomers can be produced at an extra cost. We investigated an affordable technique that produces only one synthetic product: short-chain (C7-C8) acyl lipidation. Acyl lipidation of Ala-Ala-Pro-Val, an inhibitor of human neutrophil elastase (HNE; believed to lead to abnormal tissue destruction and disease development), was investigated as an alternative to LAA conjugation. The current study aimed to assess the effects of acyl lipidation (either at the N-terminal or at the C-terminal) on neutrophil elastase activity in vitro and on transdermal delivery ex vivo. The inhibitory capacity of the acyl conjugates was compared to LAA conjugates (conjugated at the N-terminal) of the same peptide. The L-stereoisomer appears to rapidly degrade, but it represents a significantly (Ppeptide (Ala-Ala-Pro-Val). Although the D-stereoisomer appears to permeate human epidermal skin sections in a better fashion than the L-stereoisomer, it is not a significantly better inhibitor of HNE than the parent peptide. Acyl lipidation (with a C7 lipid chain) at either end of the peptide substantially enhances the permeability of the peptide across human skin epidermis as well as significantly (Ppeptide is a more economical and effective alternative to LAA conjugation. PMID:27468224

  9. Structural and Functional Studies of Fatty Acyl Adenylate Ligases from E. coli and L. pneumophila

    Energy Technology Data Exchange (ETDEWEB)

    Z Zhang; R Zhou; J Sauder; P Tonge; S Burley; S Swaminathan

    2011-12-31

    Fatty acyl-AMP ligase (FAAL) is a new member of a family of adenylate-forming enzymes that were recently discovered in Mycobacterium tuberculosis. They are similar in sequence to fatty acyl-coenzyme A (CoA) ligases (FACLs). However, while FACLs perform a two-step catalytic reaction, AMP ligation followed by CoA ligation using ATP and CoA as cofactors, FAALs produce only the acyl adenylate and are unable to perform the second step. We report X-ray crystal structures of full-length FAAL from Escherichia coli (EcFAAL) and FAAL from Legionella pneumophila (LpFAAL) bound to acyl adenylate, determined at resolution limits of 3.0 and 1.85 {angstrom}, respectively. The structures share a larger N-terminal domain and a smaller C-terminal domain, which together resemble the previously determined structures of FAAL and FACL proteins. Our two structures occur in quite different conformations. EcFAAL adopts the adenylate-forming conformation typical of FACLs, whereas LpFAAL exhibits a unique intermediate conformation. Both EcFAAL and LpFAAL have insertion motifs that distinguish them from the FACLs. Structures of EcFAAL and LpFAAL reveal detailed interactions between this insertion motif and the interdomain hinge region and with the C-terminal domain. We suggest that the insertion motifs support sufficient interdomain motions to allow substrate binding and product release during acyl adenylate formation, but they preclude CoA binding, thereby preventing CoA ligation.

  10. Efficient mono-acylation of fructose by lipase-catalyzed esterification in ionic liquid co-solvents.

    Science.gov (United States)

    Li, Lu; Ji, Fangling; Wang, Jingyun; Jiang, Bo; Li, Yachen; Bao, Yongming

    2015-10-30

    Fructose monoesters are eco-friendly nonionic surfactants in various applications. Selective preparation of mono-acylated fructose is challenging due to the multiple hydroxyl sites available for acylation both chemically and enzymatically. Ionic liquids (ILs) have profound impacts not only on the reaction media but also on the catalytic properties of enzymes in the acylation process. In this study, utilizing an IL co-solvent system, selective synthesis of mono-acylated fructose with lauric acid catalyzed by immobilized Candida antarctica lipase B (CALB) was investigated. The imidazolium-based ILs selected as co-solvents with 2-methyl-2-butanol (2M2B) markedly improved the ratios of monolauroyl fructose in the presence of 60% [BMIM][TfO] (v/v) and 20% [BMIM][BF4] (v/v), in which the mono-acylated fructose was 85% and 78% respectively. Based on a Ping-Pong Bi-Bi model, a kinetic equation was fitted, by which the kinetic parameters revealed that the affinity between fructose and acyl-enzyme intermediate was enhanced. The inhibition effect of fructose on free enzyme was weakened in the presence of IL co-solvents. The conformation of CALB binding substrates also changed in the co-solvent system as demonstrated by Fourier transform infrared spectra. These results demonstrated that the variation of CALB kinetic characteristics was a crucial factor for the selectivity of mono-acylation in ILs/2M2B co-solvents. PMID:26343327

  11. Mass-tag labeling reveals site-specific and endogenous levels of protein S-fatty acylation.

    Science.gov (United States)

    Percher, Avital; Ramakrishnan, Srinivasan; Thinon, Emmanuelle; Yuan, Xiaoqiu; Yount, Jacob S; Hang, Howard C

    2016-04-19

    Fatty acylation of cysteine residues provides spatial and temporal control of protein function in cells and regulates important biological pathways in eukaryotes. Although recent methods have improved the detection and proteomic analysis of cysteine fatty (S-fatty) acylated proteins, understanding how specific sites and quantitative levels of this posttranslational modification modulate cellular pathways are still challenging. To analyze the endogenous levels of protein S-fatty acylation in cells, we developed a mass-tag labeling method based on hydroxylamine-sensitivity of thioesters and selective maleimide-modification of cysteines, termed acyl-PEG exchange (APE). We demonstrate that APE enables sensitive detection of protein S-acylation levels and is broadly applicable to different classes of S-palmitoylated membrane proteins. Using APE, we show that endogenous interferon-induced transmembrane protein 3 is S-fatty acylated on three cysteine residues and site-specific modification of highly conserved cysteines are crucial for the antiviral activity of this IFN-stimulated immune effector. APE therefore provides a general and sensitive method for analyzing the endogenous levels of protein S-fatty acylation and should facilitate quantitative studies of this regulated and dynamic lipid modification in biological systems.

  12. S-naproxen-ss-1-O-acyl glucuronide degradation kinetic studies by stopped-flow high-performance liquid chromatography-H-1 NMR and high-performance liquid chromatography-UV

    DEFF Research Database (Denmark)

    Mortensen, R. W.; Corcoran, O.; Cornett, Claus;

    2001-01-01

    Acyl-migrated isomers of drug beta -1-O-acyl glucuronides have been implicated in drug toxicity because they can bind to proteins. The acyl migration and hydrolysis of S-naproxen-beta -1-O-acyl glucuronide (S-nap-g) was followed by dynamic stopped-flow HPLC-H-1 NMR and HPLC methods. Nine first or...

  13. The pharmacokinetics of naproxen, its metabolite O-desmethylnaproxen, and their acyl glucuronides in humans. Effect of cimetidine.

    OpenAIRE

    Vree, T.B.; van den Biggelaar-Martea, M; Verwey-Van Wissen, C P; Vree, M L; Guelen, P J

    1993-01-01

    1. The pharmacokinetics of 500 mg naproxen given orally were described in 10 subjects using a direct h.p.l.c. analysis of the acyl glucuronide conjugates of naproxen and its metabolite O-desmethylnaproxen. 2. The mean elimination half-life of naproxen was 24.7 +/- 6.4 h (range 7 to 36 h). 3. Naproxen acyl glucuronide accounted for 50.8 +/- 7.3% of the dose recovered in the urine, its isomerised conjugate isoglucuronide for 6.5 +/- 2.0%, O-desmethylnaproxen acyl glucuronide for 14.3 +/- 3.4%, ...

  14. 2,4-dimethoxybenzyl: An amide protecting group for 2-acetamido glycosyl donors

    DEFF Research Database (Denmark)

    Kelly, N.M.; Jensen, Knud Jørgen

    2001-01-01

    2,4-Dimethoxybenzyl (Dmob) was used as an amide protecting group for 2-acetamido glycosyl donors. The N-Dmob group was introduced by imine formation between 2,4-dimethoxybenzaldehyde and d-glucosamine, followed by per-O-acylation, reduction to form the amine, and finally N-acetylation to give 1...

  15. Separable subgroups have bounded packing

    CERN Document Server

    Yang, Wen-yuan

    2010-01-01

    In this note, we prove that separable subgroups have bounded packing in ambient groups. The notion bounded packing was introduced by Hruska-Wise \\cite{HrWi} and in particular, our result confirms a conjecture in \\cite{HrWi} which states each subgroup of a virtually polycyclic group has the bounded packing property.

  16. Cortical Dynamics of Figure-Ground Separation in Response to 2D Pictures and 3D Scenes: How V2 Combines Border Ownership, Stereoscopic Cues, and Gestalt Grouping Rules.

    Science.gov (United States)

    Grossberg, Stephen

    2015-01-01

    The FACADE model, and its laminar cortical realization and extension in the 3D LAMINART model, have explained, simulated, and predicted many perceptual and neurobiological data about how the visual cortex carries out 3D vision and figure-ground perception, and how these cortical mechanisms enable 2D pictures to generate 3D percepts of occluding and occluded objects. In particular, these models have proposed how border ownership occurs, but have not yet explicitly explained the correlation between multiple properties of border ownership neurons in cortical area V2 that were reported in a remarkable series of neurophysiological experiments by von der Heydt and his colleagues; namely, border ownership, contrast preference, binocular stereoscopic information, selectivity for side-of-figure, Gestalt rules, and strength of attentional modulation, as well as the time course during which such properties arise. This article shows how, by combining 3D LAMINART properties that were discovered in two parallel streams of research, a unified explanation of these properties emerges. This explanation proposes, moreover, how these properties contribute to the generation of consciously seen 3D surfaces. The first research stream models how processes like 3D boundary grouping and surface filling-in interact in multiple stages within and between the V1 interblob-V2 interstripe-V4 cortical stream and the V1 blob-V2 thin stripe-V4 cortical stream, respectively. Of particular importance for understanding figure-ground separation is how these cortical interactions convert computationally complementary boundary and surface mechanisms into a consistent conscious percept, including the critical use of surface contour feedback signals from surface representations in V2 thin stripes to boundary representations in V2 interstripes. Remarkably, key figure-ground properties emerge from these feedback interactions. The second research stream shows how cells that compute absolute disparity in

  17. Profiling acylated homoserine lactones in Yersinia ruckeri and influence of exogenous acyl homoserine lactones and known quorum-sensing inhibitors on protease production

    DEFF Research Database (Denmark)

    Kastbjerg, Vicky Gaedt; Nielsen, Kristian Fog; Dalsgaard, Inger;

    2007-01-01

    produced at least eight different acylated homoserine lactones (AHLs) with N-(3-oxooctanoyl)-l-homoserine lactone (3-oxo-C8-HSL) being the dominant molecule. Also, some uncommon AHL, N-(3-oxoheptanoyl)-l-homoserine lactone (3-oxo-C7-HSL) and N-(3-oxononanoyl)-l-homoserine lactone (3-oxo-C9-HSL), were...... produced. 3-oxo-C8-HSL was detected in organs from fish infected with Y. ruckeri. Protease production was significantly lower at temperatures above 23 degrees C than below although growth was faster at the higher temperatures. Neither addition of sterile filtered high-density Y. ruckeri culture supernatant...

  18. Structure-based analysis of the molecular interactions between acyltransferase and acyl carrier protein in vicenistatin biosynthesis.

    Science.gov (United States)

    Miyanaga, Akimasa; Iwasawa, Shohei; Shinohara, Yuji; Kudo, Fumitaka; Eguchi, Tadashi

    2016-02-16

    Acyltransferases (ATs) are key determinants of building block specificity in polyketide biosynthesis. Despite the importance of protein-protein interactions between AT and acyl carrier protein (ACP) during the acyltransfer reaction, the mechanism of ACP recognition by AT is not understood in detail. Herein, we report the crystal structure of AT VinK, which transfers a dipeptide group between two ACPs, VinL and VinP1LdACP, in vicenistatin biosynthesis. The isolated VinK structure showed a unique substrate-binding pocket for the dipeptide group linked to ACP. To gain greater insight into the mechanism of ACP recognition, we attempted to crystallize the VinK-ACP complexes. Because transient enzyme-ACP complexes are difficult to crystallize, we developed a covalent cross-linking strategy using a bifunctional maleimide reagent to trap the VinK-ACP complexes, allowing the determination of the crystal structure of the VinK-VinL complex. In the complex structure, Arg-153, Met-206, and Arg-299 of VinK interact with the negatively charged helix II region of VinL. The VinK-VinL complex structure allows, to our knowledge, the first visualization of the interaction between AT and ACP and provides detailed mechanistic insights into ACP recognition by AT. PMID:26831085

  19. Characterization of Two Members among the Five ADP-Forming Acyl Coenzyme A (Acyl-CoA) Synthetases Reveals the Presence of a 2-(Imidazol-4-yl)Acetyl-CoA Synthetase in Thermococcus kodakarensis

    OpenAIRE

    Awano, Tomotsugu; Wilming, Anja; Tomita, Hiroya; Yokooji, Yuusuke; Fukui, Toshiaki; Imanaka, Tadayuki; Atomi, Haruyuki

    2014-01-01

    The genome of Thermococcus kodakarensis, along with those of most Thermococcus and Pyrococcus species, harbors five paralogous genes encoding putative α subunits of nucleoside diphosphate (NDP)-forming acyl coenzyme A (acyl-CoA) synthetases. The substrate specificities of the protein products for three of these paralogs have been clarified through studies on the individual enzymes from Pyrococcus furiosus and T. kodakarensis. Here we have examined the biochemical properties of the remaining t...

  20. Crystallization and preliminary X-ray crystallographic studies of a new class of enoyl-(acyl-carrier protein) reductase, FabV, from Vibrio fischeri

    International Nuclear Information System (INIS)

    An orthorhombic crystal of an enoyl-(acyl-carrier protein) reductase from V. fischeri was obtained and diffraction data were collected to 2.7 Å resolution. Enoyl-(acyl-carrier protein) reductase (ENR) catalyzes the last step of the fatty-acid elongation cycle of the bacterial fatty-acid biosynthesis (FAS II) pathway. Recently, a new class of ENR has been identified from Vibrio cholerae and was named FabV. In order to understand the molecular mechanism of the new class of ENR at the structural level, FabV from V. fischeri was overexpressed, purified and crystallized. Diffraction data were collected to 2.7 Å resolution from a native crystal. The crystal belonged to the orthorhombic space group P21212, with unit-cell parameters a = 123.53, b = 164.14, c = 97.07 Å. The presence of four molecules of FabV in the asymmetric unit gave a VM value of 2.81 Å3 Da−1, with a corresponding solvent content of 54.5%

  1. Synthesis, Characterization and Biological Activities of N-Acyl-3-(3-pyridyl)-5-aryl-pyrazoles

    Institute of Scientific and Technical Information of China (English)

    KANG Yan-fang; WANG Dun-jia; XU Ben-po; WEI Xian-hong; ZHENG Jing

    2013-01-01

    Ten novel N-acyl-3-(3-pyridyl)-5-aryl-pyrazoles were synthesized by Claisen condensation of the aryl methyl ketones with ethyl nicotinate,the cyclization with hydrazine hydrate and the N-acylation with acyl chloride in turn.The structures of all the compounds synthesized were confirmed by means of Fourier transform infrared(FTIR),1H NMR,mass spectroscopy and elemental analysis.The biological activities of the title compounds were examined by disc diffusion method against Escherichia coli,Staphylococcus aureus,Pyricularia oryzae and Rhizoctnia solani.All the N-acyl-3-(3-pyridyl)-5-aryl-pyrazoles exhibited a certain degree of antibacterial and antifungal activities.Comparatively,compounds 3c and 3d exhibited much significant antibacterial and antifungal activities than the other pyrazole derivatives.

  2. First evidence of Okadaic acid acyl-derivative and Dinophysistoxin-3 in mussel samples collected in Chiloe Island, Southern Chile.

    Science.gov (United States)

    García, Carlos; Pruzzo, Matías; Rodríguez-Unda, Nelson; Contreras, Cristóbal; Lagos, Néstor

    2010-06-01

    This paper shows the detection of Diarrhetic Shellfish Poison (DSP) phycotoxins, using HPLC-FLD with pre-column derivatization procedure and HPLC-MS methods, in the analysis of shellfish extracts tested positive with the official DSP mouse bioassay. The shellfish samples were collected in Chiloe Island, Southern of Chile. The amount of Dinophysistoxin-3 (DTX-3) measured in the shellfish extracts were in average above the international safe limits for DSP content in the shellfish extracts analyzed. As internal control of detection and recovery, DTX-1 analytical standard was spiked into dichloromethane-clean shellfish extracts in order to calculate de extraction recovery of DTX-1. The average recovery was 97%. From all DSP toxins analyzed, the hydrolyzed extract samples appeared mainly DTX-3 in concentrations ranging from 99.40 +/- 1.22 to 257.73 +/- 12.46 ng/g digestive-glands. The acyl-Okadaic Acid (acyl-OA) was also detected in some samples, ranging from 1.02 +/- 1.4 to 3.07. +/- 1.6 ng of DSP toxin/g digestive-glands. This is the first report of acyl-OA ever found in Chilean shellfish samples. This data shows that shellfish samples were contaminated with a complex DSP toxins profile, in which DTX-3 is the major DSP toxin component, followed by DTX-1 and the acyl-OA as the minor one. The important findings showed in this study are the presence of both acyl-derivates (DTX-3 and Acyl-OA) which are the product of a main metabolic biotransformation that occurred inside the shellfish, in order to chelate DTX-1 and OA, transforming them into DTX-3 and the acyl-OA respectively. This metabolic biotransformation must be performed to avoid self-inhibition of their Protein Phosphatase 2A done by DTX-1 and OA, since both acyl-derivates (DTX-3 and acyl-OA) do not inhibit Protein Phosphatase 2A. This complex DSP toxins profile and the permanent presence of both acyl-derivates (DTX-3 and Acyl-OA) could explain the permanent diarrhea symptoms that experience patients who have

  3. Reactivity of TEMPO anion as a nucleophile and its applications for selective transformations of haloalkanes or acyl halides to aldehydes

    OpenAIRE

    Inokuchi, Tsutomu; Kawafuchi, Hiroyuki

    2004-01-01

    Sodium 2,2,6,6-tetramethylpiperidine-N-oxide (TEMPO−Na+), generated by reduction of TEMPO· with sodium naphthalenide in THF, reacted with alkyl halides or acyl halides to produce O-alkylated or acylated TEMPOs, which were in turn oxidized with mCPBA or reduced with DIBAL-H to afford the corresponding aldehydes, thus accomplishing a new protocol for the halides-carbonyls conversion.

  4. Acyl-chain remodeling of dioctanoyl-phosphatidylcholine in Saccharomyces cerevisiae mutant defective in de novo and salvage phosphatidylcholine synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Kishino, Hideyuki; Eguchi, Hiroki; Takagi, Keiko; Horiuchi, Hiroyuki; Fukuda, Ryouichi; Ohta, Akinori, E-mail: aaohta@isc.chubu.ac.jp

    2014-03-07

    Highlights: • Dioctanoyl-PC (diC8PC) supported growth of a yeast mutant defective in PC synthesis. • diC8PC was converted to PC species containing longer acyl residues in the mutant. • Both acyl residues of diC8PC were replaced by longer fatty acids in vitro. • This system will contribute to the elucidation of the acyl chain remodeling of PC. - Abstract: A yeast strain, in which endogenous phosphatidylcholine (PC) synthesis is controllable, was constructed by the replacement of the promoter of PCT1, encoding CTP:phosphocholine cytidylyltransferase, with GAL1 promoter in a double deletion mutant of PEM1 and PEM2, encoding phosphatidylethanolamine methyltransferase and phospholipid methyltransferase, respectively. This mutant did not grow in the glucose-containing medium, but the addition of dioctanoyl-phosphatidylcholine (diC8PC) supported its growth. Analyses of the metabolism of {sup 13}C-labeled diC8PC ((methyl-{sup 13}C){sub 3}-diC8PC) in this strain using electrospray ionization tandem mass spectrometry revealed that it was converted to PC species containing acyl residues of 16 or 18 carbons at both sn-1 and sn-2 positions. In addition, both acyl residues of (methyl-{sup 13}C){sub 3}-diC8PC were replaced with 16:1 acyl chains in the in vitro reaction using the yeast cell extract in the presence of palmitoleoyl-CoA. These results indicate that PC containing short acyl residues was remodeled to those with acyl chains of physiological length in yeast.

  5. Ethylene glycol causes acyl chain disordering in liquid-crystalline, unsaturated phospholipid model membranes, as measured by 2H NMR

    OpenAIRE

    NICOLAY K; Smaal, E B; de Kruijff, B.

    1986-01-01

    2H NMR has been used to probe the effects of ethylene glycol at the level of the acyl chains in liposomes prepared from dioleoylphosphatidic acid or dioleoylphosphatidylcholine, labeled with 2H at the 11-position of both oleic acid chains. Increasing concentrations of ethylene glycol lead to a proportional and substantial decrease in the quadrupolar splittings, measured from the 2H NMR spectra of both liposomal systems, indicative of acyl chain disordering.

  6. Ethylene glycol causes acyl chain disordering in liquid-crystalline, unsaturated phospholipid model membranes, as measured by 2H NMR

    International Nuclear Information System (INIS)

    2H NMR has been used to probe the effects of ethylene glycol at the level of the acyl chains in liposomes prepared from dioleoylphosphatidic acid or dioleoylphosphatidylcholine, labeled with 2H at the 11-position of both oleic acid chains. Increasing concentrations of ethylene glycol lead to a proportional and substantial decrease in the quadrupolar splittings, measured from the 2H NMR spectra of both liposomal system, indicative of acyl chain disordering. (Auth.)

  7. The pharmacokinetics of naproxen, its metabolite O-desmethylnaproxen, and their acyl glucuronides in humans. Effect of cimetidine.

    Science.gov (United States)

    Vree, T B; Van Den Biggelaar-Martea, M; Verwey-Van Wissen, C P; Vree, M L; Guelen, P J

    1993-05-01

    1. The pharmacokinetics of 500 mg naproxen given orally were described in 10 subjects using a direct h.p.l.c. analysis of the acyl glucuronide conjugates of naproxen and its metabolite O-desmethylnaproxen. 2. The mean elimination half-life of naproxen was 24.7 +/- 6.4 h (range 7 to 36 h). 3. Naproxen acyl glucuronide accounted for 50.8 +/- 7.3% of the dose recovered in the urine, its isomerised conjugate isoglucuronide for 6.5 +/- 2.0%, O-desmethylnaproxen acyl glucuronide for 14.3 +/- 3.4%, and its isoglucuronide for 5.5 +/- 1.3%. Naproxen and O-desmethylnaproxen were excreted in negligible amounts (< 1%). 4. Even though the urine pH of the subjects was kept acid in order to stabilize the acyl glucuronides, isomerisation took place in blood. 5. The extents of plasma binding of the unconjugated compounds were 98% (naproxen) and 100% (O-desmethylnaproxen), while naproxen acyl glucuronide binding was 92%; that of its isomer isoglucuronide 66%. O-desmethylnaproxen acyl glucuronide was 72% bound and its isoglucuronide was 42% bound. 6. Cimetidine (400 mg twice daily) decreased the t1/2 of naproxen by 39-60% (mean 47.3 +/- 11.5%; P = 0.0014) from 24.7 +/- 6.4 h to 13.2 +/- 1.0 h. It increased (10%) the urinary recovery of naproxen acyl glucuronide (P = 0.0492). The urinary recoveries of naproxen isoglucuronide and O-desmethylnaproxen acyl glucuronide remained unchanged. PMID:8512758

  8. Synthesis and characterization of Trichloroisocyanouric acid functionalized mesoporous silica nanocomposite (SBA/TCCA) for the Acylation of Indole

    Indian Academy of Sciences (India)

    G ROBIN WILSON; AMIT DUBEY

    2016-08-01

    Trichloroisocyanouric acid (TCCA)-functionalized mesoporous silica nanocomposites (SBA/TCCA) were synthesized and characterized for the acylation of indole. The uniform incorporation of TCCA inside the SBA-15 matrix was confirmed by standard characterization techniques (PXRD, Adsorption studies, FT-IR, etc.). The catalytic activity studies of SBA/TCCA nanocomposites for acylation of indole showed high selectivity (60–90%) of the 3-acetyl indole compared to homogeneous TCCA (50%). The advantage of solid support for higher selectivity is also explained.

  9. SEPARATION OF PLUTONIUM

    Science.gov (United States)

    Maddock, A.G.; Smith, F.

    1959-08-25

    A method is described for separating plutonium from uranium and fission products by treating a nitrate solution of fission products, uranium, and hexavalent plutonium with a relatively water-insoluble fluoride to adsorb fission products on the fluoride, treating the residual solution with a reducing agent for plutonium to reduce its valence to four and less, treating the reduced plutonium solution with a relatively insoluble fluoride to adsorb the plutonium on the fluoride, removing the solution, and subsequently treating the fluoride with its adsorbed plutonium with a concentrated aqueous solution of at least one of a group consisting of aluminum nitrate, ferric nitrate, and manganous nitrate to remove the plutonium from the fluoride.

  10. New acylated flavone and cyanogenic glycosides from Linum grandiflorum

    DEFF Research Database (Denmark)

    Mohammed, Magdy M. D.; Christensen, Lars Porskjær; Ibrahim, Nabaweya A.;

    2009-01-01

    The first investigation of Linum grandiflorum resulted in the isolation of one new acylated flavone O-diglycoside known as luteolin 7-O-a-D-(6000-E-feruloyl)glucopyranosyl (1!2)--D-glucopyranoside, and one new cyanogenic glycoside known as 2-[(30-isopropoxy-O--D-glucopyranosyl)oxy]-2-methylbutane......The first investigation of Linum grandiflorum resulted in the isolation of one new acylated flavone O-diglycoside known as luteolin 7-O-a-D-(6000-E-feruloyl)glucopyranosyl (1!2)--D-glucopyranoside, and one new cyanogenic glycoside known as 2-[(30-isopropoxy-O--D-glucopyranosyl)oxy]-2......-methylbutanenitrile, together with four known flavonoid glycosides, three known cyanogenic glycosides and one alkyl glycoside. The new compounds were structurally elucidated via the extensive 1D, 2D NMR and DIFNOE together with ESI-TOFCID-MS/MS and HR-MALDI/MS....

  11. Structure of armadillo ACBP: a new member of the acyl-CoA-binding protein family

    International Nuclear Information System (INIS)

    The X-ray structure of the tetragonal form of apo acyl-CoA-binding protein (ACBP) from the Harderian gland of the South American armadillo Chaetophractus villosus has been solved. The X-ray structure of the tetragonal form of apo acyl-CoA-binding protein (ACBP) from the Harderian gland of the South American armadillo Chaetophractus villosus has been solved. ACBP is a carrier for activated long-chain fatty acids and has been associated with many aspects of lipid metabolism. Its secondary structure is highly similar to that of the corresponding form of bovine ACBP and exhibits the unique flattened α-helical bundle (up–down–down–up) motif reported for animal, yeast and insect ACBPs. Conformational differences are located in loops and turns, although these structural differences do not suffice to account for features that could be related to the unusual biochemistry and lipid metabolism of the Harderian gland

  12. Effect of room temperature ionic liquid structure on the enzymatic acylation of flavonoids

    DEFF Research Database (Denmark)

    Lue, Bena-Marie; Guo, Zheng; Xu, Xuebing

    2010-01-01

    Enzymatic acylation reactions of flavonoids (rutin, esculin) with long chain fatty acids (palmitic, oleic acids) were carried out in 14 different ionic liquid media containing a range of cation and anion structures. Classification of RTILs according to flavonoid solubility (using COSMO-RS) was th......Enzymatic acylation reactions of flavonoids (rutin, esculin) with long chain fatty acids (palmitic, oleic acids) were carried out in 14 different ionic liquid media containing a range of cation and anion structures. Classification of RTILs according to flavonoid solubility (using COSMO......-bonding ability) resulted in decreased yields, likely due to increased interactions with the protein structure of the lipase. Biosynthesis of rutin proceeded much slower than of esculin. All-in-all, judicious selection of RTILs was central to achieving high yields (>98% after 6 days for TOMA·TF2N) since a balance...

  13. Structure of armadillo ACBP: a new member of the acyl-CoA-binding protein family

    Energy Technology Data Exchange (ETDEWEB)

    Costabel, Marcelo D., E-mail: costabel@criba.edu.ar [Grupo de Biofísica, Departamento de Física, Universidad Nacional del Sur, Bahía Blanca (Argentina); Ermácora, Mario R. [Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes, Bernal (Argentina); Santomé, José A. [Instituto de Química y Fisicoquímica Biológicas (IQUIFYB), Facultad de Farmacia y Bioquímica (UBA-CONICET), Buenos Aires (Argentina); Alzari, Pedro M. [Unité de Biochimie Structurale, Institut Pasteur, Paris (France); Guérin, Diego M. A. [Unidad de Biofisica (CSIC-UPV/EHU), PO Box 644, E-48080 Bilbao (Spain); Grupo de Biofísica, Departamento de Física, Universidad Nacional del Sur, Bahía Blanca (Argentina)

    2006-10-01

    The X-ray structure of the tetragonal form of apo acyl-CoA-binding protein (ACBP) from the Harderian gland of the South American armadillo Chaetophractus villosus has been solved. The X-ray structure of the tetragonal form of apo acyl-CoA-binding protein (ACBP) from the Harderian gland of the South American armadillo Chaetophractus villosus has been solved. ACBP is a carrier for activated long-chain fatty acids and has been associated with many aspects of lipid metabolism. Its secondary structure is highly similar to that of the corresponding form of bovine ACBP and exhibits the unique flattened α-helical bundle (up–down–down–up) motif reported for animal, yeast and insect ACBPs. Conformational differences are located in loops and turns, although these structural differences do not suffice to account for features that could be related to the unusual biochemistry and lipid metabolism of the Harderian gland.

  14. New Acylated Flavonol Glycosides and a Phenolic Profile of Pritzelago alpina, a Forgotten Edible Alpine Plant.

    Science.gov (United States)

    Corradi, Elisabetta; De Mieri, Maria; Cadisch, Larissa; Abbet, Christian; Hamburger, Matthias; Potterat, Olivier

    2016-02-01

    Thirteen acylated flavonoid glycosides, 1-13, including eleven new congeners, 3-13, were isolated from the aerial parts of Pritzelago alpina (Brassicaceae) by a combination of column chromatography on Sephadex LH-20, and preparative and semi-preparative HPLC. The structures were established by extensive NMR and MS experiments in combination with acid hydrolysis and sugar analysis by GC/MS. The new compounds were shown to be kaempferol and quercetin glycosides acylated for most of them by a branched short chain fatty acid or a hydroxycinnamic acid residue on the sugar portion. As shown by a HPLC-DAD analysis of a MeOH extract, these compounds are the main phenolic constituents in the aerial parts of the plant. PMID:26880431

  15. A severe genotype with favourable outcome in very long chain acyl-CoA dehydrogenase deficiency

    DEFF Research Database (Denmark)

    Touma, E H; Rashed, M S; Vianey-Saban, C;

    2001-01-01

    A patient with very long chain acyl-CoA dehydrogenase (VLCAD) deficiency is reported. He had a severe neonatal presentation and cardiomyopathy. He was found to be homozygous for a severe mutation with no residual enzyme activity. Tandem mass spectrometry on dried blood spots revealed increased lo...... chain acylcarnitines. VLCAD enzyme activity was severely decreased to 2% of control levels. Dietary management consisted of skimmed milk supplemented with medium chain triglycerides and L-carnitine. Outcome was good and there was no acute recurrence.......A patient with very long chain acyl-CoA dehydrogenase (VLCAD) deficiency is reported. He had a severe neonatal presentation and cardiomyopathy. He was found to be homozygous for a severe mutation with no residual enzyme activity. Tandem mass spectrometry on dried blood spots revealed increased long...

  16. Broad-range and binary-range acyl-acyl-carrier protein thioesterases suggest an alternative mechanism for medium-chain production in seeds.

    Science.gov (United States)

    Voelker, T A; Jones, A; Cranmer, A M; Davies, H M; Knutzon, D S

    1997-06-01

    In the current model of medium-chain (C8-14) fatty acid biosynthesis in seeds, specialized FatB acyl-acyl-carrier-protein (ACP) thioesterases are responsible for the production of medium chains. We have isolated and characterized FatB cDNAs from the maturing seeds of elm (Ulmus americana) and nutmeg (Myristica fragrans), which accumulate predominantly caprate (10:0)- and myristate (14:0)-containing oils, respectively. In neither species were we able to find cDNAs encoding enzymes specialized for these chain lengths. Nutmeg FatB hydrolyses C14-18 substrates in vitro and expression in Brassica napus seeds leads to an oil enriched in C14-18 saturates. Elm FatB1 displays a binary specificity: one activity is centered on 10:0-ACP, and a second is centered on palmitate (16:0)-ACP. After expression in B. napus seeds the oil is enriched in C10-18 saturates, predominantly 16:0, 14:0, and 10:0. The composition of free fatty acids produced by elm FatB1 in Escherichia coli shifts from C14-16 to mostly C8-10 by increasing the rate of chain termination by this enzyme. These results suggest the existence of an alternative mechanism used in the evolution of medium-chain production, a model of which is presented. PMID:9193098

  17. Density functional theory studies on the nano-scaled composites consisted of graphene and acyl hydrazone molecules

    Science.gov (United States)

    Ren, J. L.; Zhou, L.; Lv, Z. C.; Ding, C. H.; Wu, Y. H.; Bai, H. C.

    2016-07-01

    Graphene, which is the first obtained single atomic layer 2D materials, has drawn a great of concern in nano biotechnology due to the unique property. On one hand, acyl hydrazone compounds belonging to the Schif bases have aroused considerable attention in medicine, pharmacy, and analytical reagent. However, few understanding about the interaction between graphene and acyl hydrazone molecules is now available. And such investigations are much crucial for the applications of these new nano-scaled composites. The current work revealed theoretical investigations on the nano-scaled composites built by acyl hydrazone molecules loaded on the surface of graphene. The relative energy, electronic property and the interaction between the counterparts of graphene/acyl hydrazone composites are investigated based on the density functional theory calculations. According to the obtained adsorption energy, the formation of the nano-scaled composite from the isolated graphene and acyl hydrazone molecule is exothermic, and thus it is energetically favorable to form these nano composites in viewpoint of total energy change. The frontier molecular orbital for the nano composite is mainly distributed at the graphene part, leading to that the energy levels of the frontier molecular orbital of the nano composites are very close to that of isolated graphene. Moreover, the counterpart interaction for the graphene/acyl hydrazone composites is also explored based on the discussions of orbital hybridization, charge redistribution and Van der Waals interaction.

  18. Acyl-CoA binding protein is an essential protein in mammalian cell lines

    DEFF Research Database (Denmark)

    Faergeman, Nils J; Knudsen, Jens; Færgeman, Nils J.

    2002-01-01

    In the present work, small interference RNA was used to knock-down acyl-CoA binding protein (ACBP) in HeLa, HepG2 and Chang cells. Transfection with ACBP-specific siRNA stopped growth, detached cells from the growth surface and blocked thymidine and acetate incorporation. The results show...... that depletion of ACBP in mammalian cells results in lethality, suggesting that ACBP is an essential protein....

  19. NMR structure of an acyl-carrier protein from Borrelia burgdorferi

    OpenAIRE

    Barnwal, Ravi P.; Van Voorhis, Wesley C.; Varani, G

    2011-01-01

    Nearly complete resonance assignment and the high-resolution NMR structure of the acyl-carrier protein from Borrelia burgdorferi, a target of the Seattle Structural Genomics Center for Infectious Disease (SSGCID) structure-determination pipeline, are reported. This protein was chosen as a potential target for drug-discovery efforts because of its involvement in fatty-acid biosynthesis, an essential metabolic pathway, in bacteria. It was possible to assign >98% of backbone resonances and >92% ...

  20. Pantoea sp. Isolated from Tropical Fresh Water Exhibiting N-Acyl Homoserine Lactone Production

    OpenAIRE

    Wen-Si Tan; Nina Yusrina Muhamad Yunos; Pui-Wan Tan; Nur Izzati Mohamad; Tan-Guan-Sheng Adrian; Wai-Fong Yin; Kok-Gan Chan

    2014-01-01

    N-Acyl homoserine lactone (AHL) serves as signaling molecule for quorum sensing (QS) in Gram-negative bacteria to regulate various physiological activities including pathogenicity. With the aim of isolating freshwater-borne bacteria that can cause outbreak of disease in plants and portrayed QS properties, environmental water sampling was conducted. Here we report the preliminary screening of AHL production using Chromobacterium violaceum CV026 and Escherichia coli [pSB401] as AHL biosensors. ...

  1. Novel Synthesis and Characterization of Thiosemicarbazone Compounds Containing 4-Acyl-2-pyrazolin-5-ones

    OpenAIRE

    Arjun K. Rana; Parekh, Nayan R.; Dabhi, Harish R.; Nadkarni, Sunil S.

    2009-01-01

    A novel synthesis of 4-acylthiosemicarbazone-3-methyl-1-(4`-methylphenyl)-2-pyrazolin-5-one by condensation of 4-acyl-3-methyl-1-(4`-methylphenyl)-2-pyrazolin-5-one with thiosemicarbazide is carried out. The compounds were characterized on the basis of elemental analysis, IR, 1H NMR, Mass, DSC and 13C NMR spectral data. The structures were investigated for their antibacterial and antifungal activity. They are very essential to study on cerebral infarction (Free radical scavenger). A single cr...

  2. Reaction of /alpha/,/beta/-unsaturated acyl isothiocyanates with salts of dithiocarbamic acids

    Energy Technology Data Exchange (ETDEWEB)

    Krus, K.; Masias, A.; Beletskaya, I.P.

    1989-01-10

    The reaction of unsaturated isothiocyanates with the sodium and calcium salts of N-alkyl- and N,N-dialkyldithiocarbamic acids was studied. Depending on the structure of the dithiocarbamate, the reaction products are thiazines or acyl dithiocarbamates. For the salts of methyldithiocarbamic acid the effect of the concentration and the nature of the metal on the relative yields of 6-phenyl-3-methylpropiorhodanine and 6-phenylpropiorhodanine was studied. A method is proposed for the synthesis of 3-substituted propiorhodanines.

  3. Gmelinosides A-L, twelve acylated iridoid glycosides from Gmelina arborea.

    Science.gov (United States)

    Hosny, M; Rosazza, J P

    1998-06-26

    Besides the known iridoids 6-O-alpha-L-rhamnopyranosylcatalpol (1), 6-O-(3"-O-trans-feruloyl)-alpha-L-rhamnopyranosylcatalpol (14), 6-O-(2"-O-acetyl-3", 4"-O-di-trans-cinnamoyl)-alpha-L-rhamnopyranosylcatalpol (15) and the known phenylpropanoid glycosides verbascoside (acteoside) and martynoside, 12 new acylated iridoid glycosides named gmelinosides A-L (2-13) have been isolated from the leaves of Gmelina arborea. These compounds were structurally characterized using a variety of spectral methods. PMID:9644056

  4. Identification and Characterization of Inhibitors of Bacterial Enoyl-Acyl Carrier Protein Reductase

    OpenAIRE

    Ling, Losee L.; Xian, Jun; Ali, Syed; Geng, Bolin; Fan, Jun; Mills, Debra M.; Arvanites, Anthony C.; Orgueira, Hernan; Ashwell, Mark A.; Carmel, Gilles; Xiang, Yibin; Moir, Donald T.

    2004-01-01

    Bacterial enoyl-acyl carrier protein reductase (ENR) catalyzes an essential step in fatty acid biosynthesis. ENR is an attractive target for narrow-spectrum antibacterial drug discovery because of its essential role in metabolism and its sequence conservation across many bacterial species. In addition, the bacterial ENR sequence and structural organization are distinctly different from those of mammalian fatty acid biosynthesis enzymes. High-throughput screening to identify inhibitors of Esch...

  5. Rimonabant is a dual inhibitor of acyl CoA:cholesterol acyltransferases 1 and 2

    OpenAIRE

    Netherland, Courtney; Thewke, Douglas P.

    2010-01-01

    Acyl-coenzymeA:cholesterol acyltransferase (ACAT) catalyzes the intracellular synthesis of cholesteryl esters (CE). Both ACAT isoforms, ACAT1 and ACAT2, play key roles in the pathophysiology of atherosclerosis and ACAT inhibition retards atherosclerosis in animal models. Rimonabant, a type 1 cannabinoid receptor (CB1) antagonist, produces anti-atherosclerotic effects in humans and animals by mechanisms which are not completely understood. Rimonabant is structurally similar to two other cannab...

  6. Ruthenium(III Chloride Catalyzed Acylation of Alcohols, Phenols, and Thiols in Room Temperature Ionic Liquids

    Directory of Open Access Journals (Sweden)

    Mingzhong Cai

    2009-09-01

    Full Text Available Ruthenium(III chloride-catalyzed acylation of a variety of alcohols, phenols, and thiols was achieved in high yields under mild conditions (room temperature in the ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim][PF6]. The ionic liquid and ruthenium catalyst can be recycled at least 10 times. Our system not only solves the basic problem of ruthenium catalyst reuse, but also avoids the use of volatile acetonitrile as solvent.

  7. Modulating plant hormones by enzyme action: The GH3 family of acyl acid amido synthetases

    OpenAIRE

    Westfall, Corey S.; Herrmann, Jonathan; Chen, Qingfeng; Wang, Shiping; Jez, Joseph M.

    2010-01-01

    Plants respond to developmental cues and environmental stresses by controlling both the level and activity of various hormones. One mechanism of modulating hormone action involves amino acid conjugation. In plants, the GH3 family of enzymes conjugates various amino acids to jasmonates, auxins and benzoates. The effect of conjugation can lead to activation, inactivation or degradation of these molecules. Although the acyl acid and amino acid specificities of a few GH3 enzymes have been examine...

  8. Ruthenium(III) Chloride Catalyzed Acylation of Alcohols, Phenols, and Thiols in Room Temperature Ionic Liquids

    OpenAIRE

    Mingzhong Cai; Pingping Wang; Wenyan Hao; Zhiwen Xi

    2009-01-01

    Ruthenium(III) chloride-catalyzed acylation of a variety of alcohols, phenols, and thiols was achieved in high yields under mild conditions (room temperature) in the ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim][PF6]). The ionic liquid and ruthenium catalyst can be recycled at least 10 times. Our system not only solves the basic problem of ruthenium catalyst reuse, but also avoids the use of volatile acetonitrile as solvent.

  9. Changes in short-chain acyl-coA dehydrogenase during rat cardiac development and stress

    OpenAIRE

    Huang, Jinxian; Xu, Lipeng; Huang, Qiuju; Luo, Jiani; Liu, Peiqing; Chen, Shaorui; Yuan, Xi; Lu, Yao; Wang, Ping; Zhou, Sigui

    2015-01-01

    This study was designed to investigate the expression of short-chain acyl-CoA dehydrogenase (SCAD), a key enzyme of fatty acid β-oxidation, during rat heart development and the difference of SCAD between pathological and physiological cardiac hypertrophy. The expression of SCAD was lowest in the foetal and neonatal heart, which had time-dependent increase during normal heart development. In contrast, a significant decrease in SCAD expression was observed in different ages of spontaneously hyp...

  10. Acyl homoserine lactone-based quorum sensing in a methanogenic archaeon

    OpenAIRE

    Zhang, Guishan; Zhang, Fan; Ding, Gang; Li, Jie; Guo, Xiaopeng; Zhu, Jinxing; Zhou, Liguang; Cai, Shichun; Liu, Xiaoli; Luo, Yuanming; Zhang, Guifeng; Shi, Wenyuan; Dong, Xiuzhu

    2012-01-01

    Acyl homoserine lactone (AHL)-based quorum sensing commonly refers to cell density-dependent regulatory mechanisms found in bacteria. However, beyond bacteria, this cell-to-cell communication mechanism is poorly understood. Here we show that a methanogenic archaeon, Methanosaeta harundinacea 6Ac, encodes an active quorum sensing system that is used to regulate cell assembly and carbon metabolic flux. The methanogen 6Ac showed a cell density-dependent physiology transition, which was related t...

  11. Prolonged QTc Interval in Association With Medium-Chain Acyl-Coenzyme A Dehydrogenase Deficiency

    OpenAIRE

    Wiles, Jason R.; Leslie, Nancy; Knilans, Timothy K.; Akinbi, Henry

    2014-01-01

    Medium-chain acyl-coenzyme A dehydrogenase (MCAD) deficiency is the most common disorder of mitochondrial fatty acid oxidation. We report a term male infant who presented at 3 days of age with hypoglycemia, compensated metabolic acidosis, hypocalcemia, and prolonged QTc interval. Pregnancy was complicated by maternal premature atrial contractions and premature ventricular contractions. Prolongation of the QTc interval resolved after correction of metabolic derangements. The newborn screen was...

  12. Proposal to study $\\overline{p}$-nucleon interactions in the Cern 2m Hydrogen and deuterium BC, with $\\overline{p}$ at the highest energies alowed by the RF separators (10-15 GeV with the present PS intensity) by the Padua and Pisa TC Groups.

    CERN Document Server

    CERN. Geneva. Track Chamber Committee

    1966-01-01

    Proposal to study $\\overline{p}$-nucleon interactions in the Cern 2m Hydrogen and deuterium BC, with $\\overline{p}$ at the highest energies alowed by the RF separators (10-15 GeV with the present PS intensity) by the Padua and Pisa TC Groups.

  13. Cationic amphiphiles with fatty acyl chain asymmetry of coconut oil deliver genes selectively to mouse lung.

    Science.gov (United States)

    Chandrashekhar, Voshavar; Srujan, Marepally; Prabhakar, Rairala; Reddy, Rakesh C; Sreedhar, Bojja; Rentam, Kiran K R; Kanjilal, Sanjit; Chaudhuri, Arabinda

    2011-03-16

    Recent structure-activity studies have revealed a dramatic influence of hydrophobic chain asymmetry in enhancing gene delivery efficacies of synthetic cationic amphiphiles (Nantz, M. H. et al. Mol. Pharmaceutics2010, 7, 786-794; Koynova, R. et al. Mol. Pharmaceutics2009, 6, 951-958). The present findings demonstrate for the first time that such a transfection enhancing influence of asymmetric hydrocarbon chains observed in pure synthetic cationic amphiphiles also works for cationic amphiphiles designed with natural, asymmetric fatty acyl chains of a food-grade oil. Herein, we demonstrate that cationic amphiphiles designed with the natural fatty acyl chain asymmetry of food-grade coconut oil are less cytotoxic and deliver genes selectively to mouse lung. Despite lauroyl chains being the major fatty acyl chains of coconut oil, both the in vitro and In vivo gene transfer efficiencies of such cationic amphiphiles were found to be remarkably superior (>4-fold) to those of their pure dilauroyl analogue. Mechanistic studies involving the technique of fluorescence resonance energy transfer (FRET) revealed higher biomembrane fusibility of the cationic liposomes of the coconut amphiphiles than that of the symmetric dilauroyl analogue. AFM study revealed pronounced fusogenic nonlamellar structures of the liposomes of coconut amphiphiles. Findings in the FRET and cellular uptake study, taken together, support the notion that the higher cellular uptake resulting from the more fusogenic nature of the liposomes of coconut amphiphiles 1 are likely to play a dominant role in making the coconut amphiphiles transfection competent.

  14. Endophytic Actinomycetes: A Novel Source of Potential Acyl Homoserine Lactone Degrading Enzymes

    Directory of Open Access Journals (Sweden)

    Surang Chankhamhaengdecha

    2013-01-01

    Full Text Available Several Gram-negative pathogenic bacteria employ N-acyl-L-homoserine lactone (HSL quorum sensing (QS system to control their virulence traits. Degradation of acyl-HSL signal molecules by quorum quenching enzyme (QQE results in a loss of pathogenicity in QS-dependent organisms. The QQE activity of actinomycetes in rhizospheric soil and inside plant tissue was explored in order to obtain novel strains with high HSL-degrading activity. Among 344 rhizospheric and 132 endophytic isolates, 127 (36.9% and 68 (51.5% of them, respectively, possessed the QQE activity. The highest HSL-degrading activity was at 151.30±3.1 nmole/h/mL from an endophytic actinomycetes isolate, LPC029. The isolate was identified as Streptomyces based on 16S  rRNA gene sequence similarity. The QQE from LPC029 revealed HSL-acylase activity that was able to cleave an amide bond of acyl-side chain in HSL substrate as determined by HPLC. LPC029 HSL-acylase showed broad substrate specificity from C6- to C12-HSL in which C10HSL is the most favorable substrate for this enzyme. In an in vitro pathogenicity assay, the partially purified HSL-acylase efficiently suppressed soft rot of potato caused by Pectobacterium carotovorum ssp. carotovorum as demonstrated. To our knowledge, this is the first report of HSL-acylase activity derived from an endophytic Streptomyces.

  15. Endophytic actinomycetes: a novel source of potential acyl homoserine lactone degrading enzymes.

    Science.gov (United States)

    Chankhamhaengdecha, Surang; Hongvijit, Suphatra; Srichaisupakit, Akkaraphol; Charnchai, Pattra; Panbangred, Watanalai

    2013-01-01

    Several Gram-negative pathogenic bacteria employ N-acyl-L-homoserine lactone (HSL) quorum sensing (QS) system to control their virulence traits. Degradation of acyl-HSL signal molecules by quorum quenching enzyme (QQE) results in a loss of pathogenicity in QS-dependent organisms. The QQE activity of actinomycetes in rhizospheric soil and inside plant tissue was explored in order to obtain novel strains with high HSL-degrading activity. Among 344 rhizospheric and 132 endophytic isolates, 127 (36.9%) and 68 (51.5%) of them, respectively, possessed the QQE activity. The highest HSL-degrading activity was at 151.30 ± 3.1 nmole/h/mL from an endophytic actinomycetes isolate, LPC029. The isolate was identified as Streptomyces based on 16S  rRNA gene sequence similarity. The QQE from LPC029 revealed HSL-acylase activity that was able to cleave an amide bond of acyl-side chain in HSL substrate as determined by HPLC. LPC029 HSL-acylase showed broad substrate specificity from C6- to C12-HSL in which C10HSL is the most favorable substrate for this enzyme. In an in vitro pathogenicity assay, the partially purified HSL-acylase efficiently suppressed soft rot of potato caused by Pectobacterium carotovorum ssp. carotovorum as demonstrated. To our knowledge, this is the first report of HSL-acylase activity derived from an endophytic Streptomyces.

  16. Role of acyl carrier protein isoforms in plant lipid metabolism: Progress report

    Energy Technology Data Exchange (ETDEWEB)

    Ohlrogge, J.B.

    1989-01-01

    Previous research from my lab has revealed that several higher plant species have multiple isoforms of acyl carrier protein (ACP) and therefore this trait appears highly conserved among higher plants. This level of conservation suggests that the existence of ACP isoforms is not merely the results of neutral gene duplications. We have developed techniques to examine a wider range of species. Acyl carrier proteins can be labelled very specifically and to high specific activity using H-palmitate and the E. coli enzyme acyl-ACP synthetase. Isoforms were then resolved by western blotting and native PAGE of H-palmitate labelled ACP's. Multiple isoforms of ACP were observed the leaf tissue of the monocots Avena sativa and Hordeum vulgare and dicots including Arabidopsis thallina, Cuphea wrightii, and Brassica napus. Lower vascular plants including the cycad, Dioon edule, Ginkgo biloba, the gymnosperm Pinus, the fern Anernia phyllitidis and Psilotum nudum, the most primitive known extant vascular plant, were also found to have multiple ACP isoforms as were the nonvascular liverwort, Marchantia and moss, Polytrichum. Therefore, the development of ACP isoforms occurred early in evolution. However, the uniellular alge Chlamydomonas and Dunaliella and the photosynthetic cyanobacteria Synechocystis and Agmnellum have only a single elecrophotetic form of ACP. Thus, multiple forms of ACP do not occur in all photosynthetic organisms but may be associated with multicellular plants.

  17. Exploring the Leishmania Hydrophilic Acylated Surface Protein B (HASPB) Export Pathway by Live Cell Imaging Methods.

    Science.gov (United States)

    MacLean, Lorna; Price, Helen; O'Toole, Peter

    2016-01-01

    Leishmania major is a human-infective protozoan parasite transmitted by the bite of the female phlebotomine sand fly. The L. major hydrophilic acylated surface protein B (HASPB) is only expressed in infective parasite stages suggesting a role in parasite virulence. HASPB is a "nonclassically" secreted protein that lacks a conventional signal peptide, reaching the cell surface by an alternative route to the classical ER-Golgi pathway. Instead HASPB trafficking to and exposure on the parasite plasma membrane requires dual N-terminal acylation. Here, we use live cell imaging methods to further explore this pathway allowing visualization of key events in real time at the individual cell level. These methods include live cell imaging using fluorescent reporters to determine the subcellular localization of wild type and acylation site mutation HASPB18-GFP fusion proteins, fluorescence recovery after photobleaching (FRAP) to analyze the dynamics of HASPB in live cells, and live antibody staining to detect surface exposure of HASPB by confocal microscopy. PMID:27665560

  18. Binding of acylated peptides and fatty acids to phospholipid vesicles: pertinence to myristoylated proteins.

    Science.gov (United States)

    Peitzsch, R M; McLaughlin, S

    1993-10-01

    We studied the binding of fatty acids and acylated peptides to phospholipid vesicles by making electrophoretic mobility and equilibrium dialysis measurements. The binding energies of the anionic form of the fatty acids and the corresponding acylated glycines were identical; the energies increased by 0.8 kcal/mol per number of carbons in the acyl chain (Ncarbon = 10, 12, 14, 16), a value identical to that for the classical entropy-driven hydrophobic effect discussed by Tanford [The Hydrophobic Effect (1980) Wiley, New York]. The unitary Gibbs free binding energy, delta Gou, of myristoylated glycine, 8 kcal/mol, is independent of the nature of the electrically neutral lipids used to form the vesicles. Similar binding energies were obtained with other myristoylated peptides (e.g., Gly-Ala, Gly-Ala-Ala). The 8 kcal/mol, which corresponds to an effective dissociation constant of 10(-4) M for myristoylated peptides with lipids, provides barely enough energy to attach a myristoylated protein in the cytoplasm to the plasma membrane. Thus, other factors that reduce (e.g., hydrophobic interaction of myristate with the covalently attached protein) or enhance (e.g., electrostatic interactions of basic residues with acidic lipids; protein-protein interactions with intrinsic receptor proteins) the interaction of myristoylated proteins with membranes are likely to be important and may cause reversible translocation of these proteins to the membrane.(ABSTRACT TRUNCATED AT 250 WORDS)

  19. In Vitro Acylation of Okadaic Acid in the Presence of Various Bivalves’ Extracts

    Directory of Open Access Journals (Sweden)

    Mari Yotsu-Yamashita

    2013-01-01

    Full Text Available The dinoflagellate Dinophysis spp. is responsible for diarrhetic shellfish poisoning (DSP. In the bivalves exposed to the toxic bloom of the dinoflagellate, dinophysistoxin 3 (DTX3, the 7-OH acylated form of either okadaic acid (OA or DTX1, is produced. We demonstrated in vitro acylation of OA with palmitoyl CoA in the presence of protein extract from the digestive gland, but not other tissues of the bivalve Mizuhopecten yessoensis. The yield of 7-O-palmitoyl OA reached its maximum within 2 h, was the highest at 37 °C followed by 28 °C, 16 °C and 4 °C and was the highest at pH 8 in comparison with the yields at pH 6 and pH 4. The transformation also proceeded when the protein extract was prepared from the bivalves Corbicula japonica and Crassostrea gigas. The OA binding protein OABP2 identified in the sponge Halichondria okadai was not detected in the bivalve M. yessoensis, the bivalve Mytilus galloprovincialis and the ascidian Halocynthia roretzi, though they are known to accumulate diarrhetic shellfish poisoning toxins. Since DTX3 does not bind to protein phosphatases 1 and 2A, the physiological target for OA and DTXs in mammalian cells, the acylation of DSP toxins would be related to a detoxification mechanism for the bivalve species.

  20. An oleate 12-hydroxylase from Ricinus communis L. is a fatty acyl desaturase homolog

    Energy Technology Data Exchange (ETDEWEB)

    Van De Loo, F.J. [Univ. of Kentucky, Lexington, KY (United States); Broun, P.; Turner, S.; Somerville, C. [Carnegie Institution of Washington, Stanford, CA (United States)

    1995-07-18

    Recent spectroscopic evidence implicating a binuclear iron site at the reaction center of fatty acyl desaturases suggested to us that certain fatty acyl hydroxylases may share significant amino acid sequence similarity with desaturases. To test this theory, we prepared a cDNA library from developing endosperm of the castor-oil plant (Ricinus communis L.) and obtained partial nucleotide sequences for 468 anonymous clones that were not expressed at high levels in leaves, a tissue deficient in 12-hydroxyoleic acid. This resulted in the identification of several cDNA clones encoding a polypeptide of 387 amino acids with a predicted molecular weight of 44,407 and with {approx}67% sequence homology to microsomal oleate desaturase from Arabidopsis. Expression of a full-length clone under control of the cauliflower mosaic virus 35S promoter in transgenic tobacco resulted in the accumulation of low levels of 12-hydroxyoleic acid in seeds, indicating that the clone encodes the castor oleate hydroxylase. These results suggest that fatty acyl desaturases and hydroxylases share similar reaction mechanisms and provide an example of enzyme evolution. 26 refs., 6 figs., 1 tab.

  1. Acyl Chain Disorder and Azelaoyl Orientation in Lipid Membranes Containing Oxidized Lipids.

    Science.gov (United States)

    Mendes Ferreira, Tiago; Sood, Rohit; Bärenwald, Ruth; Carlström, Göran; Topgaard, Daniel; Saalwächter, Kay; Kinnunen, Paavo K J; Ollila, O H Samuli

    2016-06-28

    Oxidized phospholipids occur naturally in conditions of oxidative stress and have been suggested to play an important role in a number of pathological conditions due to their effects on a lipid membrane acyl chain orientation, ordering, and permeability. Here we investigate the effect of the oxidized phospholipid 1-palmitoyl-2-azelaoyl-sn-glycero-3-phosphocholine (PazePC) on a model membrane of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) using a combination of (13)C-(1)H dipolar-recoupling nuclear magnetic resonance (NMR) experiments and united-atom molecular dynamics (MD) simulations. The obtained experimental order parameter SCH profiles show that the presence of 30 mol % PazePC in the bilayer significantly increases the gauche content of the POPC acyl chains, therefore decreasing the thickness of the bilayer, although with no stable bilayer pore formation. The MD simulations reproduce the disordering effect and indicate that the orientation of the azelaoyl chain is highly dependent on its protonation state with acyl chain reversal for fully deprotonated states and a parallel orientation along the interfacial plane for fully protonated states, deprotonated and protonated azelaoyl chains having negative and positive SCH profiles, respectively. Only fully or nearly fully protonated azelaoyl chain are observed in the (13)C-(1)H dipolar-recoupling NMR experiments. The experiments show positive SCH values for the azelaoyl segments confirming for the first time that oxidized chains with polar termini adopt a parallel orientation to the bilayer plane as predicted in MD simulations. PMID:27260273

  2. Cloning of a palmitoyl-acyl carrier protein thioesterase from oil palm.

    Science.gov (United States)

    Othman, A; Lazarus, C; Fraser, T; Stobart, K

    2000-12-01

    A palmitoyl-acyl carrier protein (ACP) thioesterase cDNA clone was isolated from an oil palm cDNA library. The cDNA was expressed in Escherichia coli as a glutathione S-transferase fusion protein and a crude bacterial extract was assayed for acyl-CoA-hydrolysing activity. The recombinant enzyme was able to hydrolyse medium- and long-chain acyl-CoAs. Northern-blot analysis showed a high level of gene expression in leaf, flower and 15-, 17- and 18-week mesocarp tissues. Low-level gene expression was detected in germinated seedlings and 8- and 12-week mesocarp tissues, but no transcript was detected in any kernel tissues. Southern-blot analysis indicated the presence of a single gene and we have also isolated a genomic clone using the cDNA as a probe. Two genomic fragments were subcloned and a 7 kb contiguous stretch of the oil palm genome was sequenced. Comparison of this sequence with the cDNA sequence identified a putative 93 amino acid transit peptide, most of which is missing from the cDNA. The coding region of the gene consisted of seven exons and six introns. PMID:11171146

  3. Gene cloning, expression analysis of JcACP (Acyl Carrier Protein) in Jatropha curcas L. and its prokaryotical expression

    Institute of Scientific and Technical Information of China (English)

    JIANG Lu-ding; LI Xiao-hui

    2008-01-01

    Objective To clone the ACP (acyl carrier protein) gene in Jatropha curcas L., a potential antitumour and anti-fungal plant. And to determinate the expression of ACP in Jatropha curcas L. Methods A cDNA clone encoding ACP (acyl carrier protein) was isolated from Jatropha curcas L. endosperm eDNA library by random sequencing. The expression of ACP gene was investigated by semi-quantitative RT-PCR in leaves, stems and seeds of J. curca. The expression of ACP was also investigated in germinating seeds. The fragment encoding ACP protein in J. curca, was inserted into a prokaryotic expression vector pET28a( + ). The gene was overexpressed in E. coli BL21 to produce abundant protein. Immunohistochemical analysis was used to detect the expression of ACP in different tissues of J. curca. Results The cDNA sequence was 806 bp in length and the ORF was 393 bp. The predicted molecular weight of the putative protein was 14.4 kD, pI = 5.2. It contained a 4'-phosphopantetheine-binding motif. This prosthetic group can be combined with Serine of ACP protein. Semi-quantitative RT-PCR analysis showed that ACP gene was expressed in leaves, stems and seeds of J. curcas. The expression level of ACP was the highest in seeds and it was not detected in roots. After seeds germinated, the expression level of ACP in seeds increased progressively and reached a peak at 96 h. After induced by IPTG, SDS-PAGE analysis showed that the ACP protein of 20 kD was expressed. Immunohistochemical analysis showed that ACP specifical expressed abundantly in embyo of the seeds, and it was not detected in roots and the emdosperm while expressed in leaves and stems. Conclusions A cDNA clone encoding ACP which had all the typical characteristics of ACPs was isolated. It was expressed successfully in E. coli. The results of semi-quantitative RT-PCR analysis and immunohistochemieal analysis were very similar, which showed that the expression of ACP in J. curcas, was abundant in seeds. The results indicated the

  4. Chelation-assisted Pd-catalysed ortho-selective oxidative C-H/C-H cross-coupling of aromatic carboxylic acids with arenes and intramolecular Friedel-Crafts acylation: one-pot formation of fluorenones.

    Science.gov (United States)

    Sun, Denan; Li, Bijin; Lan, Jingbo; Huang, Quan; You, Jingsong

    2016-03-01

    Pd-Catalysed ortho-selective oxidative C-H/C-H cross-coupling of aromatic carboxylic acids with arenes and subsequent intramolecular Friedel-Crafts acylation has been accomplished for the first time through a chelation-assisted C-H activation strategy. Starting from the readily available substrates, a variety of fluorenone derivatives are obtained in one pot. The direct use of naturally occurring carboxylic acid functionalities as directing groups avoids unnecessary steps for installation and removal of an extra directing group. PMID:26861768

  5. Cell adhesion, ammonia removal and granulation of autotrophic nitrifying sludge facilitated by N-acyl-homoserine lactones.

    Science.gov (United States)

    Li, An-Jie; Hou, Bao-Lian; Li, Mei-Xi

    2015-11-01

    In this study, six N-acyl-homoserine lactone (AHL) molecules (C6-HSL, C8-HSL, C10-HSL, 3-oxo-C6-HSL, 3-oxo-C8-HSL and 3-oxo-C10-HSL) were each dosed into a bioreactor and seeded using autotrophic nitrifying sludge (ANS). The effects of the AHLs on cell adhesion, nitrification and sludge granulation were investigated. The results indicated that the efficiencies of cell adhesion and ammonia removal both had a close correlation with the side chain length and β position substituent group of the AHLs. The best-performing AHL in terms of accelerating bacterial attached-growth was 3-oxo-C6-HSL, whereas C6-HSL outperformed the others in terms of the ammonia degradation rate. The addition of 3-oxo-C6-HSL or C6-HSL increased the biomass growth rate, microbial activity, extracellular proteins and nitrifying bacteria, which can accelerate the formation of nitrifying granules. Consequently, selecting AHL molecules that could improve bacteria in attached-growth mode and nitrification efficiency simultaneously will most likely facilitate the rapid granulation of nitrifying sludge.

  6. Interaction of O-acylated chitosans with biomembrane models: probing the effects from hydrophobic interactions and hydrogen bonding.

    Science.gov (United States)

    Pavinatto, Adriana; Souza, Adriano L; Delezuk, Jorge A M; Pavinatto, Felippe J; Campana-Filho, Sérgio P; Oliveira, Osvaldo N

    2014-02-01

    One of the major challenges in establishing the mechanisms responsible for the chitosan action in biomedical applications lies in the determination of the molecular-level interactions with the cell membrane. In this study, we probed hydrophobic interactions and H-bonding in experiments with O,O'-diacetylchitosan (DACT) and O,O'-dipropionylchitosan (DPPCT) incorporated into monolayers of distinct phospholipids, the zwitterionic dipalmitoyl phosphatidyl choline (DPPC), and the negatively charged dipalmitoyl phosphatidyl glycerol (DPPG) and dimyristoyl phosphatidic acid (DMPA). The importance of hydrophobic interactions was confirmed with the larger effects observed for DACT and DPPCT than for parent chitosan (Chi), particularly for the more hydrophobic DPPCT. Such larger effects were noted in surface pressure isotherms and elasticity of the monolayers. Since H-bonding is hampered for the chitosan derivatives, which have part of their hydroxyl groups shielded by O-acylation, these effects indicate that H-bonding does not play an important role in the chitosan-membrane interactions. Using polarization-modulated infrared reflection absorption (PM-IRRAS) spectroscopy, we found that the chitosan derivatives were incorporated into the hydrophobic chain of the phospholipids, even at high surface pressures comparable to those in a real cell membrane. Taken together, these results indicate that the chitosan derivatives containing hydrophobic moieties would probably be more efficient than parent chitosan as antimicrobial agents, where interaction with the cell membrane is crucial.

  7. The quorum sensing molecule N-acyl homoserine lactone produced by Acinetobacter baumannii displays antibacterial and anticancer properties.

    Science.gov (United States)

    John, James; Saranathan, Rajagopalan; Adigopula, Lakshmi Narayana; Thamodharan, Vasanth; Singh, Satya Prakash; Lakshmi, T Pragna; CharanTej, Mallu Abhiram; Rao, R Srinivasa; Krishna, R; Rao, H Surya Prakash; Prashanth, K

    2016-10-01

    Secretory N-acyl homoserine lactones (AHLs) mediate quorum sensing (QS) in bacteria. AHLs are shown to be inhibitory for an unrelated group of bacteria and might mimic host signalling elements, thereby subverting the regulatory events in host cells. This study investigated the AHL produced by Acinetobacter baumannii and analysed its effect on other bacterial species and mammalian cells. Chemically characterized AHL had an m/z value of 325 with a molecular formula C18H31NO4 and showed its inhibitory potential against Staphylococcus aureus. Molecular docking studies identified D-alanine-D-alanine synthetase A, a cell wall synthesizing enzyme of S. aureus having a strong binding affinity towards AHL. Electron microscopy showed the disruption and sloughing off of the S. aureus cell wall when treated with AHL. In vitro experiments revealed that this bacteriostatic AHL showed time-dependent activity and induced apoptosis in cancer cell lines. This compound could be a potential structural backbone for constructing new AHL analogues against S. aureus. The findings emphasize the need to re-evaluate all previously characterized AHLs for any additional new biological functions other than QS. PMID:27643959

  8. Separation anxiety in children

    Science.gov (United States)

    ... the child experiences anxiety when separated from the primary caregiver (usually the mother). ... Excessive distress when separated from the primary caregiver ... of separation Reluctance to go to sleep without the primary ...

  9. Separation Anxiety (For Parents)

    Science.gov (United States)

    ... 5 Things to Know About Zika & Pregnancy Separation Anxiety KidsHealth > For Parents > Separation Anxiety Print A A ... both of you get through it. How Separation Anxiety Develops Babies adapt pretty well to other caregivers. ...

  10. Fictional Separation Logic

    DEFF Research Database (Denmark)

    Jensen, Jonas Buhrkal; Birkedal, Lars

    2012-01-01

    Separation logic formalizes the idea of local reasoning for heap-manipulating programs via the frame rule and the separating conjunction P * Q, which describes states that can be split into \\emph{separate} parts, with one satisfying P and the other satisfying Q. In standard separation logic...... overlap. We demonstrate, via a range of examples, how fictional separation logic can be used to reason locally and modularly about mutable abstract data types, possibly implemented using sophisticated sharing. Fictional separation logic is defined on top of standard separation logic, and both the meta......, separation means physical separation. In this paper, we introduce \\emph{fictional separation logic}, which includes more general forms of fictional separating conjunctions P * Q, where "*" does not require physical separation, but may also be used in situations where the memory resources described by P and Q...

  11. Efficient production of di- and tri-acylated mannosylerythritol lipids as glycolipid biosurfactants by Pseudozyma parantarctica JCM 11752(T).

    Science.gov (United States)

    Morita, Tomotake; Konishi, Masaaki; Fukuoka, Tokuma; Imura, Tomohiro; Sakai, Hideki; Kitamoto, Dai

    2008-01-01

    Mannosylerythritol lipids (MELs) are one of the most promising biosurfactants known, because of their multifunctionality and biocompatibility. In order to attain an efficient production of MELs, Pseudozyma parantarctica JCM 11752(T), which is a newly identified strain of the genus, was examined for the productivity of MELs at different culture conditions. The yeast strain showed significant cell growth and production of di-acylated MELs even at 36 degrees C. In contrast, on conventional high-level MEL producers including P. rugulosa, the MEL yield considerably decreased with an increase of the cultivation temperature at over 30 degrees C. On P. parantarctica, soybean oil and sodium nitrate were the best carbon and nitrogen sources, respectively. Under the optimal conditions on a shake-flask culture at 34 degrees C, the amount of di-acylated MELs reached over 100 g/L by intermittent feeding of only soybean oil. Interestingly, the yeast strain produced tri-acylated MELs as well as di-acylated ones when grown on the medium containing higher soybean oil concentrations than 8% (vol/vol). The production of tri-acylated MELs was significantly accelerated at between 34 and 36 degrees C. With 20 % (vol/vol) of soybean oil at 34 degrees C, the yield of tri-acylated MELs reached 22.7 g/L. The extracellular lipase activity considerably depended on the culture temperature, and became the maximum at 34 degrees C; this would bring the accelerated production of tri-acylated MELs. Accordingly, the present strain of P. parantarctica provided high efficiency in MEL production at elevated temperatures compared to conventional MEL producers, and would thus be highly advantageous for the commercial production of the promising biosurfactants. PMID:18781056

  12. ACYL-ACYL CARRIER PROTEIN DESATURASE2 and 3 Are Responsible for Making Omega-7 Fatty Acids in the Arabidopsis Aleurone.

    Science.gov (United States)

    Bryant, Fiona M; Munoz-Azcarate, Olaya; Kelly, Amélie A; Beaudoin, Frédéric; Kurup, Smita; Eastmond, Peter J

    2016-09-01

    Omega-7 monounsaturated fatty acids (ω-7s) are specifically enriched in the aleurone of Arabidopsis (Arabidopsis thaliana) seeds. We found significant natural variation in seed ω-7 content and used a Multiparent Advanced Generation Inter-Cross population to fine-map a major quantitative trait loci to a region containing ACYL-ACYL CARRIER PROTEIN DESATURASE1 (AAD1) and AAD3 We found that AAD3 expression is localized to the aleurone where mutants show an approximately 50% reduction in ω-7 content. By contrast, AAD1 is localized to the embryo where mutants show a small reduction in ω-9 content. Enzymatic analysis has previously shown that AAD family members possess both stearoyl- and palmitoyl-ACP Δ(9) desaturase activity, including the predominant isoform SUPPRESSOR OF SALICYLIC ACID INSENSITIVE2. However, aad3 ssi2 aleurone contained the same amount of ω-7s as aad3 Within the AAD family, AAD3 shares the highest degree of sequence similarity with AAD2 and AAD4. Mutant analysis showed that AAD2 also contributes to ω-7 production in the aleurone, and aad3 aad2 exhibits an approximately 85% reduction in ω-7s Mutant analysis also showed that FATTY ACID ELONGASE1 is required for the production of very long chain ω-7s in the aleurone. Together, these data provide genetic evidence that the ω-7 pathway proceeds via Δ(9) desaturation of palmitoyl-ACP followed by elongation of the product. Interestingly, significant variation was also identified in the ω-7 content of Brassica napus aleurone, with the highest level detected being approximately 47% of total fatty acids. PMID:27462083

  13. ACYL-ACYL CARRIER PROTEIN DESATURASE2 and 3 Are Responsible for Making Omega-7 Fatty Acids in the Arabidopsis Aleurone.

    Science.gov (United States)

    Bryant, Fiona M; Munoz-Azcarate, Olaya; Kelly, Amélie A; Beaudoin, Frédéric; Kurup, Smita; Eastmond, Peter J

    2016-09-01

    Omega-7 monounsaturated fatty acids (ω-7s) are specifically enriched in the aleurone of Arabidopsis (Arabidopsis thaliana) seeds. We found significant natural variation in seed ω-7 content and used a Multiparent Advanced Generation Inter-Cross population to fine-map a major quantitative trait loci to a region containing ACYL-ACYL CARRIER PROTEIN DESATURASE1 (AAD1) and AAD3 We found that AAD3 expression is localized to the aleurone where mutants show an approximately 50% reduction in ω-7 content. By contrast, AAD1 is localized to the embryo where mutants show a small reduction in ω-9 content. Enzymatic analysis has previously shown that AAD family members possess both stearoyl- and palmitoyl-ACP Δ(9) desaturase activity, including the predominant isoform SUPPRESSOR OF SALICYLIC ACID INSENSITIVE2. However, aad3 ssi2 aleurone contained the same amount of ω-7s as aad3 Within the AAD family, AAD3 shares the highest degree of sequence similarity with AAD2 and AAD4. Mutant analysis showed that AAD2 also contributes to ω-7 production in the aleurone, and aad3 aad2 exhibits an approximately 85% reduction in ω-7s Mutant analysis also showed that FATTY ACID ELONGASE1 is required for the production of very long chain ω-7s in the aleurone. Together, these data provide genetic evidence that the ω-7 pathway proceeds via Δ(9) desaturation of palmitoyl-ACP followed by elongation of the product. Interestingly, significant variation was also identified in the ω-7 content of Brassica napus aleurone, with the highest level detected being approximately 47% of total fatty acids.

  14. Expression and induction of secretory phospholipase A2 group IB in brain

    DEFF Research Database (Denmark)

    Kolko, Miriam; Christoffersen, Nanna R; Varoqui, Hélène;

    2005-01-01

    Secretory phospholipases A2 (sPLA2) form a diverse family of enzymes involved in physiologic and pathologic processes. Common among all sPLA2 is the ability to cleave acyl groups of phospholipids at C2 of the glycerol backbone, thereby releasing fatty acid and a lysophospholipid. Several sPLA2 ha...

  15. Anti-cancer agents based on N-acyl-2, 3-dihydro-1H-pyrrolo[2,3-b] quinoline derivatives and a method of making

    Science.gov (United States)

    Gakh, Andrei; Krasavin, Mikhail; Karapetian, Ruben; Rufanov, Konstantin A; Konstantinov, Igor; Godovykh, Elena; Soldatkina, Olga; Sosnov, Andrey V

    2013-04-16

    The present disclosure relates to novel compounds that can be used as anti-cancer agents in the prostate cancer therapy. In particular, the invention relates to N-acyl derivatives of 2,3-dihydro-1H-pyrrolo[2,3-b]quinolines having the structural Formula (I), ##STR00001## stereoisomers, tautomers, racemics, prodrugs, metabolites thereof, or pharmaceutically acceptable salt and/or solvate thereof. The meaning of R1 is independently selected from H; C1-C6 Alkyl, cyclo-Alkyl or iso-Alkyl substituents; R2 is selected from C1-C6 Alkyl, cyclo-Alkyl or iso-Alkyl; substituted or non-substituted, fused or non-fused to substituted or non-substituted aromatic ring, aryl or heteroaryl groups. The invention also relates to methods for preparing said compounds, and to pharmaceutical compositions comprising said compounds.

  16. Acyl secoiridoids and antifungal constituents from Gentiana macrophylla.

    Science.gov (United States)

    Tan, R X; Wolfender, J L; Zhang, L X; Ma, W G; Fuzzati, N; Marston, A; Hostettmann, K

    1996-07-01

    LC-UV-mass spectrometry and bioassay co-directed fractionation of an aqueous acetone extract of the roots of Gentiana macrophylla gave three new chromene derivatives and two novel and six known secoiridoids, along with kurarinone, kushenol I, beta-sitosterol, stigmasterol, daucosterol, beta-sitosterol-3-O-gentiobioside, alpha-amyrin, oleanolic acid, isovitexin, gentiobiose and methyl 2-hydroxy-3-(1-beta-D-glucopyranosyl)oxybenzoate. The structures of the new products were established from spectral and chemical evidence as 2-methoxyanofinic acid and macrophyllosides A-D. The six known secoiridoids were gentiopicroside, sweroside, 6'-O-beta-D-glucosylgentiopicroside, 6'-O-beta-D-glucosylsweroside, trifloroside and rindoside. The new acid (2-methoxyanofinic acid), its methyl ester, kurarinone and kushenol I were shown to be active against the plant pathogenic fungus Cladosporium cucumerinum. The methyl ester and kurarinone inhibited also the growth of the human pathogenic yeast Candida albicans. Structure-activity relationships were studied. Thus, addition of a methoxyl group to the benzene nucleus of anofinic acid (2,2-dimethyl-2H-1-benzopyran-6-carboxylic acid) increased the antifungal activity remarkably whereas glycosylation at the carboxylic moiety was found to remove the activity. Esterification of the new acid induced its activity against C. albicans, but decreased its growth inhibition properties against C. cucumerinum. Hydroxylation of kurarinone at the 3 beta-position removed its activity against C. albicans and decreased the inhibition of C. cucumerinum. In addition, the chemotaxonomic significance of the identified constituents is discussed. PMID:9397205

  17. Fatty acyl chain-dependent but charge-independent association of the SH4 domain of Lck with lipid membranes

    Indian Academy of Sciences (India)

    Anoop Rawat; Avaronnan Harishchandran; Ramakrishnan Nagaraj

    2013-03-01

    The SH4 domain of Src family of nonreceptor protein tyrosine kinases represents the extreme N-terminal 1–16 amino acid region which mediates membrane association of these proteins and facilitates their functions. The SH4 domains among Src members lack well-defined sequence consensus and vary in the net charge. However, they readily anchor to the cytoplasmic face of the plasma membrane upon fatty acid acylation. Here, we report the membrane association of differentially acylated SH4 domain of Lck kinase, which has net negative charge at physiological pH. Our results suggest that despite the net negative charge, the SH4 domain of Lck associates with membranes upon fatty acid acylation. While myristoylation at the N-terminus is sufficient for providing membrane anchorage, multiple acylation determines orientation of the peptide chain with respect to the lipid bilayer. Hence, fatty acylation serves more than just a lipid anchor. It has an important role in regulating the spatial orientation of the peptide domain with respect to the lipid bilayer, which could be important for the interaction of the other domains of these kinases with their partners.

  18. Acyl-chain remodeling of dioctanoyl-phosphatidylcholine in Saccharomyces cerevisiae mutant defective in de novo and salvage phosphatidylcholine synthesis.

    Science.gov (United States)

    Kishino, Hideyuki; Eguchi, Hiroki; Takagi, Keiko; Horiuchi, Hiroyuki; Fukuda, Ryouichi; Ohta, Akinori

    2014-03-01

    A yeast strain, in which endogenous phosphatidylcholine (PC) synthesis is controllable, was constructed by the replacement of the promoter of PCT1, encoding CTP:phosphocholine cytidylyltransferase, with GAL1 promoter in a double deletion mutant of PEM1 and PEM2, encoding phosphatidylethanolamine methyltransferase and phospholipid methyltransferase, respectively. This mutant did not grow in the glucose-containing medium, but the addition of dioctanoyl-phosphatidylcholine (diC8PC) supported its growth. Analyses of the metabolism of (13)C-labeled diC8PC ((methyl-(13)C)3-diC8PC) in this strain using electrospray ionization tandem mass spectrometry revealed that it was converted to PC species containing acyl residues of 16 or 18 carbons at both sn-1 and sn-2 positions. In addition, both acyl residues of (methyl-(13)C)3-diC8PC were replaced with 16:1 acyl chains in the in vitro reaction using the yeast cell extract in the presence of palmitoleoyl-CoA. These results indicate that PC containing short acyl residues was remodeled to those with acyl chains of physiological length in yeast.

  19. Application of hydrogen recovery by membrane separation in Heihua Group%膜分离回收氢技术在黑化集团硝铵厂的应用

    Institute of Scientific and Technical Information of China (English)

    贾红

    2012-01-01

    In this paper, the important role of membrane separation technology for hydrogen recovery in the optimized process of synthetic ammonia production was described. To dissolve the problem such as the membrane separation system was flooded, the low recovery and concentration could not meet the design requirements and the requirement of hydrogen peroxide production should be followed, the process of the membrane system was changed and the operation parameters were optimized, which improve the recovery and concentration of hydrogen. Considerable economic benefits can be obtained after the implementation of this optimization.%介绍了膜分离回收氢气技术在优化合成氨生产工艺中的重要作用.针对膜分离系统被水淹泡,分离出渗透H2的浓度及回收率不能满足设计要求及H2O2生产需求问题,通过改造膜系统流程并优化操作指标,找出提高H2回收率及浓度方案,实施后,取得可观的经济效益.

  20. Expression and Characterization of a Thermostable Acyl-peptide Releasing Enzyme ST0779 from Sulfolobus tokodaii

    Institute of Scientific and Technical Information of China (English)

    LI Rong; ZHANG Fei; CAO Shu-gui; XIE Gui-qiu; GAO Ren-jun

    2012-01-01

    Acyl-peptide releasing enzyme(AARE) belongs to a serine peptidase family and catalyzes the NH2-terminal hydrolysis of Nα-acylpeptides to release Nα-acylated amino acids.ORF0779(ORF=open reading frame)from thermophilic archaea Sulfolobus tokodaii(ST0779) was cloned and expressed in E.coti BL21 and the expressed protein was identified as a thermostable AARE.The target protein could be optimally overexpressed in E.coli at 30 ℃ for 8 h with 0.1 mmol/L isopropyl β-dthiogalactoside(IPTG).The crude enzyme was heated at 70 ℃ for 30 min,and then the target protein could account for above 40% of the total protein.The purification fold was 27 and the enzyme showed both esterase activity and peptidase activity.The optimal temperature and pH for ST0779 were 70 ℃and 8.0 when Ac-Ala3 was used as substrate.The half-life of the enzyme(0.2 mg/mL) at 90 ℃ was about 16 h,indicating that the enzyme exhibits a favorable thermostability.The activity of ST0779 could still remain over 85% after being treated at 25 ℃ in different buffers with pH range from 6.0 to10.0 for 24 h,which indicates ST0779 is stable in neutral or slight alkali environment.Under neutral or slightly alkali conditions,the enzyme exhibits really high catalytic efficiency against acyl-peptide,and the optimal substrate is Ac-Ala3.Most metal ions have no inhibition effect on the activity of ST0779,while 4% activity of ST0779 is inhibited in the presence of K+.This enzyme was supposed to be applied in the analysis of protein sequencing and the synthesis of small peptides.

  1. Acyl-Homoserine Lactone Recognition and Response Hindering the Quorum-Sensing Regulator EsaR

    OpenAIRE

    Daniel J Schu; Scruggs, Jessica M.; Jared S Geissinger; Katherine G Michel; Stevens, Ann M.

    2014-01-01

    During quorum sensing in the plant pathogen Pantoea stewartii subsp. stewartii, EsaI, an acyl-homoserine lactone (AHL) synthase, and the transcription factor EsaR coordinately control capsular polysaccharide production. The capsule is expressed only at high cell density when AHL levels are high, leading to inactivation of EsaR. In lieu of detailed structural information, the precise mechanism whereby EsaR recognizes AHL and is hindered by it, in a response opposite to that of most other LuxR ...

  2. Very long-chain acyl CoA dehydrogenase deficiency which was accepted as infanticide.

    Science.gov (United States)

    Eminoglu, Tuba F; Tumer, Leyla; Okur, Ilyas; Ezgu, Fatih S; Biberoglu, Gursel; Hasanoglu, Alev

    2011-07-15

    Very-long-chain acyl-coenzyme A (CoA) dehydrogenase deficiency (VLCADD) (OMIM #201475) is an autosomal recessive disorder of fatty acid oxidation. Major phenotypic expressions are hypoketotic hypoglycemia, hepatomegaly, cardiomyopathy, myopathy, rhabdomyolysis, elevated creatinine kinase, and lipid infiltration of liver and muscle. At the same time, it is a rare cause of Sudden Infant Death Syndrome (SIDS) or unexplained death in the neonatal period [1-4]. We report a patient with VLCADD whose parents were investigated for infanticide because her three previous siblings had suddenly died after normal deliveries.

  3. Regulation of lipolytic activity by long-chain acyl-coenzyme A in islets and adipocytes

    DEFF Research Database (Denmark)

    Hu, Liping; Deeney, Jude T; Nolan, Christopher J;

    2005-01-01

    normal and hormone-sensitive lipase (HSL)-null mice and in phosphatase-treated islets, indicating that the stimulatory effect was neither on HSL nor phosphorylation dependent. In contrast, we reproduced the previously published observations showing inhibition of HSL activity by LC-CoA in adipocytes....... The inhibitory effect of LC-CoA on adipocyte HSL was dependent on phosphorylation and enhanced by acyl-CoA-binding protein (ACBP). In contrast, the stimulatory effect on islet lipase activity was blocked by ACBP, presumably due to binding and sequestration of LC-CoA. These data suggest the following intertissue...

  4. Synthesis of new 3-and 4-substituted analogues of acyl homoserine lactone quorum sensing autoinducers

    DEFF Research Database (Denmark)

    Olsen, Jacob Alsbæk; Severinsen, Rune Eg; Rasmussen, Thomas Bovbjerg;

    2002-01-01

    The quorum sensing mechanism in Gram-negative bacteria uses small intercellular signal molecules, N-acyl-homoserine lactones (AHLs), to control transcription of specific genes in relation to population density. In this communication, we describe the parallel synthesis of new AHL analogues, in which...... substituents have been introduced into the 3- and 4-positions of the lactone ring. These analogues have been screened for their ability to activate and inhibit a Vibrio fischeri LuxI/LuxR-derived quorum sensing reporter system....

  5. The Bacillus subtilis Acyl Lipid Desaturase Is a Δ5 Desaturase

    Science.gov (United States)

    Altabe, Silvia G.; Aguilar, Pablo; Caballero, Gerardo M.; de Mendoza, Diego

    2003-01-01

    Bacillus subtilis was recently reported to synthesize unsaturated fatty acids (UFAs) with a double bond at positions Δ5, Δ7, and Δ9 (M. H. Weber, W. Klein, L. Muller, U. M. Niess, and M. A. Marahiel, Mol. Microbiol. 39:1321-1329, 2001). Since this finding would have considerable importance in the double-bond positional specificity displayed by the B. subtilis acyl lipid desaturase, we have attempted to confirm this observation. We report that the double bond of UFAs synthesized by B. subtilis is located exclusively at the Δ5 position, regardless of the growth temperature and the length chain of the fatty acids. PMID:12730185

  6. Synthesis and Molecular Structure of Bis-Ferrocene-Containing Acyl Thiourea Derivatives

    Institute of Scientific and Technical Information of China (English)

    XU Yan; FU Yong; RAN Chun-Ling; SONG Mao-Ping

    2003-01-01

    @@ Ferrocene is a compound with excellent stability. In addition, it has very favourable electrochemical properties. So the synthesis, structure, electrochemistry and coordination behaviors of ferrocene-derivatives have attracted considerable attention in recent years.[1,2] Electrondonating atoms such as N, S, O in the derivatives are known for their coordination particularly with transition metals. [3] Two new bis-ferrocene-containing acyl thiourea derivatives are synthesized. The derivatives are confirmed by IR spectrum, 1H NMR and elemental analysis. These compoundshave many electrondonating atoms and two ferrocenes. The structure of one compound is shown below. The study onelectrochemistry and coordination behaviors is in the progress.

  7. Profiling Protein Kinases and Other ATP Binding Proteins in Arabidopsis Using Acyl-ATP Probes*

    OpenAIRE

    Villamor, J. G.; Kaschani, F.; Colby, T; Oeljeklaus, J.; Zhao, D; Kaiser, M.; Patricelli, M. P.; R. A. L. van der Hoorn

    2013-01-01

    Many protein activities are driven by ATP binding and hydrolysis. Here, we explore the ATP binding proteome of the model plant Arabidopsis thaliana using acyl-ATP (AcATP)1 probes. These probes target ATP binding sites and covalently label lysine residues in the ATP binding pocket. Gel-based profiling using biotinylated AcATP showed that labeling is dependent on pH and divalent ions and can be competed by nucleotides. The vast majority of these AcATP-labeled proteins are known ATP binding prot...

  8. Formation of upper rim acylated calix[4]arenes using a sacrifici al zinc anode

    OpenAIRE

    Louati, Alain; Vataj, Rame; Gabelica, Valérie; Lejeune, Manuel; MATT, DOMINIQUE

    2005-01-01

    A straightforward electrosynthetic method is described, which allows upper rim acylation of non-p-halogenated calix[4]-arenes. For example, a solution of tetrapropoxycalix[4]arene 4 was electrolysed in the presence of ZnBr2, in an undivided cell fitted with a sacrificial zinc anode using pure acetonitrile as solvent, yielding an organozinc species, which was then treated with acetyl chloride in the presence of a palladium catalyst to afford 5,11-diacety1-25,26,27,28-tetrapropoxycalix[4]arene ...

  9. Ground-State Distortion in N-Acyl-tert-butyl-carbamates (Boc) and N-Acyl-tosylamides (Ts): Twisted Amides of Relevance to Amide N-C Cross-Coupling.

    Science.gov (United States)

    Szostak, Roman; Shi, Shicheng; Meng, Guangrong; Lalancette, Roger; Szostak, Michal

    2016-09-01

    Amide N-C(O) bonds are generally unreactive in cross-coupling reactions employing low-valent transition metals due to nN → π*C═O resonance. Herein we demonstrate that N-acyl-tert-butyl-carbamates (Boc) and N-acyl-tosylamides (Ts), two classes of acyclic amides that have recently enabled the development of elusive amide bond N-C cross-coupling reactions with organometallic reagents, are intrinsically twisted around the N-C(O) axis. The data have important implications for the design of new amide cross-coupling reactions with the N-C(O) amide bond cleavage as a key step. PMID:27480938

  10. Fatty acid biosynthesis in Pseudomonas aeruginosa: cloning and characterization of the fabAB operon encoding beta-hydroxyacyl-acyl carrier protein dehydratase (FabA) and beta-ketoacyl-acyl carrier protein synthase I (FabB).

    OpenAIRE

    Hoang, T.T.; Schweizer, H P

    1997-01-01

    The Pseudomonas aeruginosa fabA and fabB genes, encoding beta-hydroxyacyl-acyl carrier protein dehydratase and beta-ketoacyl-acyl carrier protein synthase I, respectively, were cloned, sequenced, and expressed in Escherichia coli. Northern analysis demonstrated that fabA and fabB are cotranscribed and most probably form a fabAB operon. The FabA and FabB proteins were similar in size and amino acid composition to their counterparts from Escherichia coli and to the putative homologs from Haemop...

  11. Structural elucidation and biological activity of acyl-homoserine lactones from the phytopathogen Pantoea ananatis Serrano 1928.

    Science.gov (United States)

    Pomini, Armando M; Araújo, Welington L; Marsaioli, Anita J

    2006-08-01

    In Gram-negative bacteria, the acyl-homoserine lactones (acyl-HSLs) are the main signaling substances employed in cell-to-cell communication systems. This paper describes the chemical characterization of acyl-HSLs produced by the worldwide-spread phytopathogen Pantoea ananatis (Serrano 1928) by using gas chromatography-electron impact mass spectrometry. The absolute configuration of the major identified substance, (S)-(--)-N-hexanoyl-HSL, was determined with gas chromatography-flame ionization detection with a chiral capillary column. Biological activities of extracts, fractions, and synthetic products were evaluated with the specific reporter Agrobacterium tumefaciensNTL4(pZLR4) in beta-galactosidase expression assays. PMID:16900431

  12. Chemical probing of the human sirtuin 5 active site reveals its substrate acyl specificity and peptide-based inhibitors.

    Science.gov (United States)

    Roessler, Claudia; Nowak, Theresa; Pannek, Martin; Gertz, Melanie; Nguyen, Giang T T; Scharfe, Michael; Born, Ilona; Sippl, Wolfgang; Steegborn, Clemens; Schutkowski, Mike

    2014-09-26

    Sirtuins are NAD(+)-dependent deacetylases acting as sensors in metabolic pathways and stress response. In mammals there are seven isoforms. The mitochondrial sirtuin 5 is a weak deacetylase but a very efficient demalonylase and desuccinylase; however, its substrate acyl specificity has not been systematically analyzed. Herein, we investigated a carbamoyl phosphate synthetase 1 derived peptide substrate and modified the lysine side chain systematically to determine the acyl specificity of Sirt5. From that point we designed six potent peptide-based inhibitors that interact with the NAD(+) binding pocket. To characterize the interaction details causing the different substrate and inhibition properties we report several X-ray crystal structures of Sirt5 complexed with these peptides. Our results reveal the Sirt5 acyl selectivity and its molecular basis and enable the design of inhibitors for Sirt5. PMID:25111069

  13. Synthesis of Duloxetine Derivatives with Acyl%度洛西汀酰基衍生物的合成

    Institute of Scientific and Technical Information of China (English)

    章文军; 苑志忠; 张静

    2012-01-01

    抗抑郁药度洛西汀与取代酰氯反应合成了四个新的度洛西汀酰基衍生物——N-取代酰基-N-甲基-3-(1-萘氧基)-3-(2-噻吩基)丙胺,其结构经1 H NMR,IR和MS表征.%Four novel duloxetine derivatives with acyl, TV-(substituted acyl)-N-methyl-3-(l-naphtha lenyloxy)-3-(2-thienyl)propanamines, were synthesized by the reaction of duloxetine with substituted acyl chlorides. The structures were characterized by 1H NMR, IR and MS.

  14. Acylation Modification of Antheraea pernyi Silk Fibroin Using Succinic Anhydride and Its Effects on Enzymatic Degradation Behavior

    Directory of Open Access Journals (Sweden)

    Xiufang Li

    2013-01-01

    Full Text Available The degradation rate of tissue engineering scaffolds should match the regeneration rate of new tissues. Controlling the degradation behavior of silk fibroin is an important subject for silk-based tissue engineering scaffolds. In this study, Antheraea pernyi silk fibroin was successfully modified with succinic anhydride and then characterized by zeta potential, ninhydrin method, and FTIR. In vitro, three-dimensional scaffolds prepared with modified silk fibroin were incubated in collagenase IA solution for 18 days to evaluate the impact of acylation on the degradation behavior. The results demonstrated that the degradation rate of modified silk fibroin scaffolds was more rapid than unmodified ones. The content of the β-sheet structure in silk fibroin obviously decreased after acylation, resulting in a high degradation rate. Above all, the degradation behavior of silk fibroin scaffolds could be regulated by acylation to match the requirements of various tissues regeneration.

  15. Mimics of the self-assembling chlorosomal bacteriochlorophylls: regio- and stereoselective synthesis and stereoanalysis of acyl(1-hydroxyalkyl)porphyrins.

    Science.gov (United States)

    Balaban, Teodor Silviu; Bhise, Anil Dnyanoba; Bringmann, Gerhard; Bürck, Jochen; Chappaz-Gillot, Cyril; Eichhöfer, Andreas; Fenske, Dieter; Götz, Daniel C G; Knauer, Michael; Mizoguchi, Tadashi; Mössinger, Dennis; Rösner, Harald; Roussel, Christian; Schraut, Michaela; Tamiaki, Hitoshi; Vanthuyne, Nicolas

    2009-10-14

    Diacylation of copper 10,20-bis(3,5-di-tert-butylphenylporphyrin) using Friedel-Crafts conditions at short reaction times, high concentrations of catalyst, and 0-4 degrees C affords only the 3,17-diacyl-substituted porphyrins, out of the 12 possible regioisomers. At longer reaction times and higher temperatures, the 3,13-diacyl compounds are also formed, and the two isomers can be conveniently separated by normal chromatographic techniques. Monoreduction of these diketones affords in good yields the corresponding acyl(1-hydroxyalkyl)porphyrins, which after zinc metalation are mimics of the natural chlorosomal bacteriochlorophyll (BChl) d. Racemate resolution by HPLC on a variety of chiral columns was achieved and further optimized, thus permitting easy access to enantiopure porphyrins. Enantioselective reductions proved to be less effective in this respect, giving moderate yields and only 79% ee in the best case. The absolute configuration of the 3(1)-stereocenter was assigned by independent chemical and spectroscopic methods. Self-assembly of a variety of these zinc BChl d mimics proves that a collinear arrangement of the hydroxyalkyl substituent with the zinc atom and the carbonyl substituent is not a stringent requirement, since both the 3,13 and the 3,17 regioisomers self-assemble readily as the racemates. Interestingly, the separated enantiomers self-assemble less readily, as judged by absorption, fluorescence, and transmission electron microscopy studies. Circular dichroism spectra of the self-assemblies show intense Cotton effects, which are mirror-images for the two 3(1)-enantiomers, proving that the supramolecular chirality is dependent on the configuration at the 3(1)-stereocenter. Upon disruption of these self-assemblies with methanol, which competes with zinc ligation, only very weak monomeric Cotton effects are present. The favored heterochiral self-assembly process may also be encountered for the natural BChls. This touches upon the long

  16. Miniaturization of Separation Systems and Its Applications

    Institute of Scientific and Technical Information of China (English)

    Yoshihiro Saito

    2003-01-01

    Development of miniaturized separation system consisted of microscale extraction and liquid phase separation processes has been reviewed.Various types of novel bonded stationary phases have been developed on the basis of the systematic analysis for the retention behavior of polycyclic aromatic hydrocarbons on experimentally synthesized phases. In this review, the miniaturization of microscale sample preparation technique and the effective on-line coupling to microcolumn liquid phase separations are also described especially focusing on the approach by the author's group. The novel use of synthetic polymer filaments as the stationary phase and extraction media in those microscale separation systems will be introduced along with the applications in gas chromatographic separation.

  17. Plasma concentrations of acyl-ghrelin are associated with average daily gain and feeding behavior in grow-finish pigs.

    Science.gov (United States)

    Lents, C A; Brown-Brandl, T M; Rohrer, G A; Oliver, W T; Freking, B A

    2016-04-01

    The objectives of this study were to determine the effect of sex, sire line, and litter size on concentrations of acyl-ghrelin and total ghrelin in plasma of grow-finish pigs and to understand the relationship of plasma concentrations of ghrelin with feeding behavior, average daily gain (ADG), and back fat in grow-finish swine. Yorkshire-Landrace crossbred dams were inseminated with semen from Yorkshire, Landrace, or Duroc sires. Within 24 h of birth, pigs were cross-fostered into litter sizes of normal (N; >12 pigs/litter) or small (S; ≤ 9 pigs/litter). At 8 wk of age, pigs (n = 240) were blocked by sire breed, sex, and litter size and assigned to pens (n = 6) containing commercial feeders modified with a system to monitor feeding behavior. Total time eating, number of daily meals, and duration of meals were recorded for each individual pig. Body weight was recorded every 4 wk. Back fat and loin eye area were recorded at the conclusion of the 12-wk feeding study. A blood sample was collected at week 7 of the study to quantify concentrations of acyl- and total ghrelin in plasma. Pigs from small litters weighed more (P sires had lesser (P sires, but plasma concentrations of total ghrelin were not affected by sire breed. Concentrations of acyl-ghrelin were positively correlated with the number of meals and negatively correlated with meal length and ADG (P < 0.05). A larger number of short-duration meals may indicate that pigs with greater concentrations of acyl-ghrelin consumed less total feed, which likely explains why they were leaner and grew more slowly. Acyl-ghrelin is involved in regulating feeding behavior in pigs, and measuring acyl-ghrelin is important when trying to understand the role of this hormone in swine physiology. PMID:26808977

  18. DISTINCT TRANSCRIPTIONAL REGULATION OF LONG-CHAIN ACYL-COA SYNTHETASE ISOFORMS AND CYTOSOLIC THIOESTERASE 1 IN THE RODENT HEART BY FATTY ACIDS AND INSULIN

    Science.gov (United States)

    The molecular mechanism(s) responsible for channeling long-chain fatty acids (LCFAs) into oxidative versus nonoxidative pathways is (are) poorly understood in the heart. Intracellular LCFAs are converted to long-chain fatty acyl-CoAs (LCFA-CoAs) by a family of long-chain acyl-CoA synthetases (ACSLs)...

  19. Appearance and distribution of regioisomers in metallo- and serine-protease-catalysed acylation of sucrose in N,N-dimethylformamide

    DEFF Research Database (Denmark)

    Lie, Aleksander; Meyer, Anne S.; Pedersen, Lars Haastrup

    2014-01-01

    The appearance and distribution of monoester regioisomers were investigated in the virtually irreversible acylation of sucrose with the enol ester, vinyl laurate, as acyl donor catalysed by serine proteases and a metalloprotease in the hydrophilic, aprotic solvent N,N-dimethylformamide. Sucrose...

  20. Acyl-CoA-binding protein (ACBP) localizes to the endoplasmic reticulum and Golgi in a ligand-dependent manner in mammalian cells

    DEFF Research Database (Denmark)

    Hansen, Jesper S; Færgeman, Nils J; Kragelund, Birthe B;

    2008-01-01

    In the present study, we microinjected fluorescently labelled liver bovine ACBP (acyl-CoA-binding protein) [FACI-50 (fluorescent acyl-CoA indicator-50)] into HeLa and BMGE (bovine mammary gland epithelial) cell lines to characterize the localization and dynamics of ACBP in living cells. Results...... vesicular trafficking....

  1. Determination of hydrophobic coenzyme a esters and other lipids using a biosensor comprising a modified coenzyme a- and acyl-coa binding protein (acbp)

    DEFF Research Database (Denmark)

    2002-01-01

    , food and feed preparations, tissue extracts, acyl-CoA synthetase reaction media and various laboratory conditions using a modified Coenzyme A- and acyl-CoA binding protein (ACBP) is provided. Furthermore the invention relates to a construct comprising a peptide and a signal moiety for performing...

  2. Preparation of 5-acyl- and 5-aryl-substituted 1-(benzyloxy)pyrazoles via directed ortho-lithiation/transmetalation and palladium catalyzed cross- coupling

    DEFF Research Database (Denmark)

    Kristensen, Jesper Langgaard; Begtrup, M.; Vedsø, P.

    1998-01-01

    Palladium(0) catalyzed cross-coupling of 1-(benzyloxy)pyrazol-5-ylzinc halides 3a,b, prepared by transmetalation of 1-(benzyloxy)-5-lithiopyrazole (2), with acyl chlorides produced 5 acyl-1-(benzyloxy)pyrazoles 4a-d in high yields. Similar coupling of the pyrazol-5-ylzinc halide with amino...

  3. Bioconversion of α-linolenic acid to n-3 LCPUFA and expression of PPAR-alpha, acyl Coenzyme A oxidase 1 and carnitine acyl transferase I are incremented after feeding rats with α-linolenic acid-rich oils.

    Science.gov (United States)

    González-Mañán, Daniel; Tapia, Gladys; Gormaz, Juan Guillermo; D'Espessailles, Amanda; Espinosa, Alejandra; Masson, Lilia; Varela, Patricia; Valenzuela, Alfonso; Valenzuela, Rodrigo

    2012-07-01

    High dietary intake of n-6 fatty acids in relation to n-3 fatty acids may generate health disorders, such as cardiovascular and other chronic diseases. Fish consumption rich in n-3 fatty acids is low in Latin America, it being necessary to seek other alternatives to provide α-linolenic acid (ALA), precursor of n-3 LCPUFA (EPA and DHA). Two innovative oils were assayed, chia (Salvia hispanica) and rosa mosqueta (Rosa rubiginosa). This study evaluated hepatic bioconversion of ALA to EPA and DHA, expression of PPAR-α, acyl-Coenzyme A oxidase 1 (ACOX1) and carnitine acyltransferase I (CAT-I), and accumulation of EPA and DHA in plasma and adipose tissue in Sprague-Dawley rats. Three experimental groups were fed 21 days: sunflower oil (SFO, control); chia oil (CO); rosa mosqueta oil (RMO). Fatty acid composition of total lipids and phospholipids from plasma, hepatic and adipose tissue was assessed by gas-liquid chromatography and TLC. Expression of PPAR-α (RT-PCR) and ACOX1 and CAT-I (Western blot). CO and RMO increased plasma, hepatic and adipose tissue levels of ALA, EPA and DHA and decreased n-6:n-3 ratio compared to SFO (p < 0.05, One-way ANOVA and Newman-Keuls test). CO increased levels of ALA and EPA compared to RMO (p < 0.05). No significant differences were observed for DHA levels. CO also increased the expression of PPAR-α, ACOX1 and CAT-I. Only CAT-I levels were increased by RO. CO and RMO may be a nutritional alternative to provide ALA for its bioconversion to EPA and DHA, and to increase the expression of PPAR-α, ACOX1 and CAT-I, especially CO-oil.

  4. Separation and preconcentration of platinum-group metals from spent autocatalysts solutions using a hetero-polymeric S, N-containing sorbent and determination by high-resolution continuum source graphite furnace atomic absorption spectrometry.

    Science.gov (United States)

    Eskina, Vasilina V; Dalnova, Olga A; Filatova, Daria G; Baranovskaya, Vasilisa B; Karpov, Yuri A

    2016-10-01

    This paper describes the potential of high-resolution continuum source graphite furnace atomic absorption spectrometry for determination of Pt, Pd and Rh after separation and concentration by original in-house developed heterochain polymer S, N-containing sorbent. The methods of sample preparation of spent ceramic-based autocatalysts were considered, two of which were used: autoclave decomposition in mixture of acids HCl:HNO3 (3:1) and high-temperature melting with K2S2O7. Both methods anyway limit the direct determination of analytes by HR CS GFAAS. Using the first method it is an incomplete digestion of spent autocatalysts samples, since the precipitate is Si, and the rhodium metal dissolves with difficulty and partially passes into solution. In contrast to the first method, the second method allow to completely transfer analytes into solution, however, the background signal produced by the chemical composition of the flux, overlaps the analytical zone. It was found, that Pt, Pd and Rh contained in the spent ceramic automotive catalysts could be effectively separated and concentrated by heterochain polymer S, N-containing sorbent, which has high sorption capacity, selectivity and resistant to dilute acids. The chosen HR CS GFAAS analysis conditions enable us to determine Pt, Pd and Rh with good metrological characteristics. The concentrations of Pt, Pd and Rh in two samples of automobile exhaust catalysts were found in range of 0.00015-0.00050; 0.170-0.189; 0.0180-0.0210wt%, respectively. The relative standard deviation obtained by HR CS GFAAS was not more than 5%. Limits of detection by HR CS GFAAS achieved were 6.2·10(-6)wt% for Pt, 1.8·10(-6)wt% for Pd, and 3.4·10(-6)wt% for Rh. Limits of determination achieved by HR CS GFAAS were 1.1·10(-5)wt% for Pt, 6.9·10(-5)wt% for Pd, and 8.3·10(-5)wt% for Rh. To control the accuracy of PGM in sorption concentrates by HR CS GFAAS method, it was appropriate to conduct an inter-method comparative experiment. The

  5. Isotope separation principles

    Energy Technology Data Exchange (ETDEWEB)

    Benedict, Manson

    1963-03-15

    Isotope separation theory of ideal cascades is discussed. It is shown how the most important characteristics of an isotope separation process can be worked out from the compositions and flow rates of the feed and product streams. These characteristics include plant size, dependence of product rate on product purity, minimum power consumption, costs of isotope separation, minimum time for reaching steady production, and effect of third component on process performance and product costs. The concepts of value functions, separative power, and separative work are used to derive the characteristics, and the analogy between isotope separation theory and thermodynamics is emphasized. (D.L.C.)

  6. MAA-1, a novel acyl-CoA-binding protein involved in endosomal vesicle transport in Caenorhabditis elegans

    DEFF Research Database (Denmark)

    Larsen, Morten K; Tuck, Simon; Færgeman, Nils J.;

    2006-01-01

    membrane-associated member of the acyl-CoA-binding protein family. We show that in Caenorhabditis elegans, MAA-1 localizes to intracellular membrane organelles in the secretory and endocytic pathway and that mutations in maa-1 reduce the rate of endosomal recycling. A lack of maa-1 activity causes a change...... in endosomal morphology. Although in wild type, many endosomal organelles have long tubular protrusions, loss of MAA-1 activity results in loss of the tubular domains, suggesting the maa-1 is required for the generation or maintenance of these domains. Furthermore, we demonstrate that MAA-1 binds fatty acyl...

  7. Enhancement of E. coli acyl-CoA synthetase FadD activity on medium chain fatty acids

    OpenAIRE

    Ford, Tyler J.; Way, Jeffrey C

    2015-01-01

    FadD catalyses the first step in E. coli beta-oxidation, the activation of free fatty acids into acyl-CoA thioesters. This activation makes fatty acids competent for catabolism and reduction into derivatives like alcohols and alkanes. Alcohols and alkanes derived from medium chain fatty acids (MCFAs, 6–12 carbons) are potential biofuels; however, FadD has low activity on MCFAs. Herein, we generate mutations in fadD that enhance its acyl-CoA synthetase activity on MCFAs. Homology modeling reve...

  8. Functional Analysis of Long-chain Acyl-CoA Synthetase 1 in 3T3-L1 Adipocytes*

    OpenAIRE

    Lobo, Sandra; Wiczer, Brian M.; Bernlohr, David A

    2009-01-01

    ACSL1 (acyl-CoA synthetase 1), the major acyl-CoA synthetase of adipocytes, has been proposed to function in adipocytes as mediating free fatty acid influx, esterification, and storage as triglyceride. To test this hypothesis, ACSL1 was stably silenced (knockdown (kd)) in 3T3-L1 cells, differentiated into adipocytes, and evaluated for changes in lipid metabolism. Surprisingly, ACSL1-silenced adipocytes exhibited no significant changes in basal or insulin-stimulated long-chain fatty acid uptak...

  9. ADP-abhängige Acyl-CoA Synthetasen in Archaea, Bacteria und Eukarya: Charakterisierung, Funktion und Phylogenie

    OpenAIRE

    Schmidt, Marcel Clemens

    2013-01-01

    ADP-bildende Acetyl-CoA Synthetasen (ACD) gehören wie die Succinyl-CoA Synthetasen (SCS) zur Proteinfamilie der NDP-bildenden Acyl-CoA Synthetasen. Beide Enzyme sind ubiquitär in allen drei Domänen des Lebens vorhanden und katalysieren die NDP- und Pi-abhängige Umsetzung von Acyl-CoA Estern (Acetyl-CoA bzw. Succinyl-CoA) zu den kor-respondierenden Säuren unter der Bildung von NTP über Substratstufenphosphorylierung. Die ACD-Reaktion wurde erstmals in dem Acetat bildenden Protisten Entamo...

  10. Lipases in green chemistry: acylation and alcoholysis on steroids and nucleosides.

    Science.gov (United States)

    Baldessari, Alicia; Iglesias, Luis E

    2012-01-01

    In this article, we describe the application of lipases in acylation and alcoholysis reactions on steroids and nucleosides. In the field of steroids, a variety of acetyl and fatty acid derivatives of androstanes, pregnanes, and cholestanes have been prepared through lipase-catalyzed acylation and alcoholysis reactions taking advantage of the high regio- and stereoselectivity of these enzymes. The substrates as well as the products show a high degree of biological activity as neurosteroids, hormones, and glucocorticoids. The regioselective preparation of diacylated nucleosides by means of an enzymatic alcoholysis allowed the synthesis of nucleosides prodrugs or modified nucleosides. The quantitative full deacylation and dealkoxycarbonylation of nucleosides and steroids is a mild synthetic method for the deprotection of these labile compounds. Some of the reported steroid and nucleoside products are novel, and it is not possible to obtain them satisfactorily by following traditional synthetic procedures. The advantages presented by this methodology, such as selectivity, mild reaction conditions, and low environmental impact, make the lipases an important tool in the application of the principles of Green Chemistry, offering a convenient way to prepare derivatives of natural compounds with a great potential in the pharmaceutical industry.

  11. Deciphering the roles of acyl-CoA-binding proteins in plant cells.

    Science.gov (United States)

    Lung, Shiu-Cheung; Chye, Mee-Len

    2016-09-01

    Lipid trafficking is vital for metabolite exchange and signal communications between organelles and endomembranes. Acyl-CoA-binding proteins (ACBPs) are involved in the intracellular transport, protection, and pool formation of acyl-CoA esters, which are important intermediates and regulators in lipid metabolism and cellular signaling. In this review, we highlight recent advances in our understanding of plant ACBP families from a cellular and developmental perspective. Plant ACBPs have been extensively studied in Arabidopsis thaliana (a dicot) and to a lesser extent in Oryza sativa (a monocot). Thus far, they have been detected in the plasma membrane, vesicles, endoplasmic reticulum, Golgi apparatus, apoplast, cytosol, nuclear periphery, and peroxisomes. In combination with biochemical and molecular genetic tools, the widespread subcellular distribution of respective ACBP members has been explicitly linked to their functions in lipid metabolism during development and in response to stresses. At the cellular level, strong expression of specific ACBP homologs in specialized cells, such as embryos, stem epidermis, guard cells, male gametophytes, and phloem sap, is of relevance to their corresponding distinct roles in organ development and stress responses. Other interesting patterns in their subcellular localization and spatial expression that prompt new directions in future investigations are discussed. PMID:26340904

  12. Age dependent accumulation of N-acyl-ethanolamine phospholipids in ischemic rat brain

    DEFF Research Database (Denmark)

    Moesgaard, B.; Petersen, G.; Hansen, Harald S.;

    2000-01-01

    N-acyl-ethanolamine phospholipids (NAPE) can be formed as a stress response during neuronal injury, and they are precursors for N-acyl- ethanolamines (NAE), some of which are endocannabinoids. The levels of NAPE accumulated during post-decapitative ischemia (6 h at 37°C) were studied in rat brains...... of various age (1, 6, 12, 19, 30, and ~70 days) by the use of P NMR spectroscopy of lipid extracts. This ability to accumulate NAPE was compared with the activity of N-acyltransferase and of NAPE-hydrolyzing phospholipase D (NAPE-PLD) in brain microsomes. These two enzymes are involved in the formation...... and degradation of NAPE, respectively. The results showed that 1) the ability to accumulate NAPE during post-decapitative ischemia is especially high in the youngest rats and is markedly reduced in older brains [in 1-day-old rat brains NAPE accumulated to 1.5% of total phospholipids, while in 30-day-old rat...

  13. Lipases in green chemistry: acylation and alcoholysis on steroids and nucleosides.

    Science.gov (United States)

    Baldessari, Alicia; Iglesias, Luis E

    2012-01-01

    In this article, we describe the application of lipases in acylation and alcoholysis reactions on steroids and nucleosides. In the field of steroids, a variety of acetyl and fatty acid derivatives of androstanes, pregnanes, and cholestanes have been prepared through lipase-catalyzed acylation and alcoholysis reactions taking advantage of the high regio- and stereoselectivity of these enzymes. The substrates as well as the products show a high degree of biological activity as neurosteroids, hormones, and glucocorticoids. The regioselective preparation of diacylated nucleosides by means of an enzymatic alcoholysis allowed the synthesis of nucleosides prodrugs or modified nucleosides. The quantitative full deacylation and dealkoxycarbonylation of nucleosides and steroids is a mild synthetic method for the deprotection of these labile compounds. Some of the reported steroid and nucleoside products are novel, and it is not possible to obtain them satisfactorily by following traditional synthetic procedures. The advantages presented by this methodology, such as selectivity, mild reaction conditions, and low environmental impact, make the lipases an important tool in the application of the principles of Green Chemistry, offering a convenient way to prepare derivatives of natural compounds with a great potential in the pharmaceutical industry. PMID:22426734

  14. Metal Chlorides Supported Solid Catalysts for F-C Acylations of Arenes

    Institute of Scientific and Technical Information of China (English)

    李阳; 刘云龙; 穆曼曼; 陈立功

    2015-01-01

    A series of metal chlorides supported solid catalysts were prepared by simple wet impregnation method. Their catalytic performances for Friedel-Crafts acylation of toluene with benzoyl chloride were evaluated and the excellent results were obtained over FeCl3/SiO2. These catalysts were characterized by BET, NH3-TPD and FT-IR of pyridine adsorption to clarify the structure-activity relationship. It was found that FeCl3/SiO2 has larger pore size and pore volume than other catalysts, which increased the accessibility of the catalyst. In addition, FeCl3/SiO2 ex-hibited higher molar ratio of Lewis acid sites and Brφnsted acid sites, which might be another reason for the in-crease of toluene conversion. Furthermore, the reaction parameters, including temperature, time and molar ratio, were optimized. Under the optimized conditions, 91.2%, conversion and 82.0%, selectivity were obtained. Mean-while, the generality of the catalyst was demonstrated by the acylations of alkyl substituted aromatics. Finally, the catalyst was reused for four runs with slight loss in catalytic activity, which attributed to the drain of the active component.

  15. Carboxylic acid terminated, solution exfoliated graphite by organic acylation and its application in drug delivery

    Indian Academy of Sciences (India)

    KOUSHIK BHOWMIK; AMRITA CHAKRAVARTY; U MANJU; GOUTAM DE; ARNAB MUKHERJEE

    2016-09-01

    Graphite nanosheets are considered as a promising material for a range of applications from flexible electronics to functional nanodevices such as biosensors, intelligent coatings and drug delivery. Chemical functionalizationof graphite nanosheets with organic/inorganic materials offers an alternative approach to control the electronic properties of graphene, which is a zero band gap semiconductor in pristine form. In this paper, we report the aromatic electrophilic substitution of solution exfoliated graphite nanosheets (SEGn). The highly conjugated π-electronic system of graphite nanosheets enable it to have an amphiphilic characteristic in aromatic substitution reactions. The substitution was achieved through Friedel–Crafts (FC) acylation reaction under mild conditions using succinic anhydride as acylating agent and anhydrous aluminum chloride as Lewisacid. Such reaction renders towards the carboxylic acid terminated graphite nanosheets (SEGn–FC) that usually requires harsh reaction conditions. The product thus obtained was characterized using various spectroscopicand microscopic techniques. Highly stable water-dispersed sodium salt of carboxylic acid terminated graphite nanosheets (SEGn–FC-Na) was also prepared. A comparative sheet-resistance measurements of SEGn, SEGn–FC and SEGn–FC-Na were also done. Finally, the anticancer drug doxorubicin (DOX) was loaded on water dispersible SEGn–FC-Na with a loading capacity of 0.266 mg mg−1 of SEGn–FC-Na and the release of DOX from this water-soluble DOX-loaded SEGn–FC-Na at two different temperatures was found to be strongly pHdependent.

  16. Association of cord blood des-acyl ghrelin with birth weight, and placental GHS-R1 receptor expression in SGA, AGA, and LGA newborns.

    Science.gov (United States)

    González-Domínguez, Martha I; Lazo-de-la-Vega-Monroy, Maria-Luisa; Zaina, Silvio; Sabanero, Myrna; Daza-Benítez, Leonel; Malacara, Juan Manuel; Barbosa-Sabanero, Gloria

    2016-07-01

    Although ghrelin in cord blood has been associated to birth weight, its role in fetal and postnatal growth has not been elucidated. The aim of this study was to analyze total ghrelin, acyl ghrelin (AG), and des-acyl ghrelin (DAG) in cord blood of newborns with idiopathic birth weight alterations, and to evaluate protein expression of placental GHS-R1, in order to investigate their correlation with birth weight and placental weight. We performed a cross-sectional comparative study in umbilical cord blood and placentas from healthy mothers of SGA, AGA, and LGA (small, adequate and large for gestational age) term newborns (n = 20 per group). Cord blood total ghrelin, AG, and DAG were measured by ELISA, and placental GHS-R1 expression was evaluated by Western blot. Cord blood DAG was higher in SGA compared to AGA newborns (902.1 ± 109.1 and 597.4 ± 58.2 pg/ml, respectively, p = 0.01) while LGA and AGA showed similar values (627.2 ± 76.4 pg/ml for LGA, p = 0.80). DAG negatively correlated with birthweight (r = -0.31, p = 0.02) and placental weight (r = -0.33, p = 0.02). No differences in AG or total ghrelin were found. GHS-R1 protein in placenta was not differentially expressed among SGA, AGA, and LGA. Our results suggest a role of DAG in intrauterine growth. Further studies are needed in order to elucidate the mechanisms by which DAG participates in fetal growth. PMID:26754660

  17. Magnetic Separation in Romania

    OpenAIRE

    Rezlescu, Nicolae; Bradu, Elena-Brandusa; Iacob, Gheorghe; Badescu, Vasile; Iacob, Lavinia

    1986-01-01

    The utilization of the magnetic separators of foreign and Romanian source is presented and the most important achievements in research, engineering design and manufacturing activity concerning the magnetic separation in Romania are reviewed.

  18. Magnetic Separation in Czechoslovakia

    OpenAIRE

    Hencl, Vladimir

    1991-01-01

    The use of magnetic separation in various mineral processing facilities in Czechoslovakia is described. The manufacture of assorted types of magnetic separation machines is highlighted. Potential applications and research and development activities are discussed.

  19. Magnetic separation of algae

    Energy Technology Data Exchange (ETDEWEB)

    Nath, Pulak; Twary, Scott N.

    2016-04-26

    Described herein are methods and systems for harvesting, collecting, separating and/or dewatering algae using iron based salts combined with a magnetic field gradient to separate algae from an aqueous solution.

  20. Successive Administration of Streptococcus Type 5 Group A Antigens and S. typhimurium Antigenic Complex Corrects Elevation of Serum Cytokine Concentration and Number of Bone Marrow Stromal Pluripotent Cells in CBA Mice Induced by Each Antigen Separately.

    Science.gov (United States)

    Gorskaya, Yu F; Danilova, T A; Grabko, V I; Nesterenko, V G

    2015-12-01

    Administration of bacterial antigens to CBA mice induced an increase in serum concentration of virtually all cytokines with a peak in 4 h after administration of S. typhimurium antigens and in 7 h after administration of streptococcus antigens. In 20 h, cytokine concentrations returned to the control level or were slightly below it. In 4 h after administration of S. typhimurium antigens preceded 3 h before by administration of streptococcus antigens, we observed a significant decrease in serum concentrations of IFN-γ, IL-10, GM-CSF, IL-12, and TNF-α, in comparison with injection S. typhimurium antigens alone and IL-5, IL-10, GM-CSF, and TNF-α in comparison with injection of streptococcus antigens alone; the concentrations of IL-2 and IFN-γ, in contrast, increased by 1.5 times in this case. In 20 h after administration of S. typhimurium antigens, the number of multipotential stromal cells (MSC) in the bone marrow and their cloning efficiency (ECF-MSC) increased by 4.8 and 4.4 times, respectively, in comparison with the control, while after administration of streptococcus antigens by 2.6 and 2.4 times, respectively. In 20 h after administration of S. typhimurium antigens preceded 3 h before by administration of streptococcus antigens, these parameters increased by 3.2 and 2.9 times, respectively, in comparison with the control, i.e. the observed increase in the level of MSC count and ECF-MSC is more consistent with the response of the stromal tissue to streptococcus antigens. Thus, successive administration of two bacterial antigens corrected both serum cytokine profiles and MSC response to administration of each antigen separately, which indicates changeability of the stromal tissue in response to changes in the immune response.

  1. Measurement of short-chain acyl-CoA dehydrogenase (SCAD) in cultured skin fibroblasts with hexanoyl-CoA as a competitive inhibitor to eliminate the contribution of medium-chain acyl-CoA dehydrogenase

    NARCIS (Netherlands)

    Niezen-Koning, K E; Wanders, R J; Nagel, G T; Sewell, A C; Heijmans, Hugo

    1994-01-01

    Short-chain acyl-CoA dehydrogenase (SCAD) deficiency has so far been reported in only very few patients. This is due, in part, to the problems involved in measuring the activity of SCAD unequivocally. The main reason for this difficulty is that butyryl-CoA, the substrate preferably used for SCAD act

  2. Magnetic Carbon Nanotubes for Protein Separation

    OpenAIRE

    Xiaobin Fan; Fengbao Zhang; Guoliang Zhang; Xiuhui Diao; Hongyu Chen

    2012-01-01

    Magnetic separation is a promising strategy in protein separation. Owing to their unique one-dimensional structures and desired magnetic properties, stacked-cup carbon nanotubes (CSCNTs) with magnetic nanoparticles trapped in their tips can serve as train-like systems for protein separation. In this study, we functionalized the magnetic CSCNTs with high density of carboxyl groups by radical addition and then anchored 3-aminophenylboronic acid (APBA) through amidation reaction to achieve orien...

  3. Use of an apparatus for separating magnetic pieces of material

    NARCIS (Netherlands)

    Rem, P.C.; Berkhout, S.P.M.

    2010-01-01

    Using of an apparatus for separating magnetic pieces of scrap-material of a first group from magnetic pieces of scrap- material of a second group, wherein a mixture of pieces of scrap-material from the first group and from the second group is collectively transported with a conveyor to a separating

  4. Rapid chemical separations

    CERN Document Server

    Trautmann, N

    1976-01-01

    A survey is given on the progress of fast chemical separation procedures during the last few years. Fast, discontinuous separation techniques are illustrated by a procedure for niobium. The use of such techniques for the chemical characterization of the heaviest known elements is described. Other rapid separation methods from aqueous solutions are summarized. The application of the high speed liquid chromatography to the separation of chemically similar elements is outlined. The use of the gas jet recoil transport method for nuclear reaction products and its combination with a continuous solvent extraction technique and with a thermochromatographic separation is presented. Different separation methods in the gas phase are briefly discussed and the attachment of a thermochromatographic technique to an on-line mass separator is shown. (45 refs).

  5. Identification of four new mutations in the short-chain acyl-CoA dehydrogenase (SCAD) gene in two patients

    DEFF Research Database (Denmark)

    Gregersen, N; Winter, V S; Corydon, M J;

    1998-01-01

    We have shown previously that a variant allele of the short-chain acyl-CoA dehydrogenase ( SCAD ) gene, 625G-->A, is present in homozygous form in 7% of control individuals and in 60% of 135 patients with elevated urinary excretion of ethylmalonic acid (EMA). We have now characterized three disease...

  6. Long-chain Acyl-CoA is not primarily increased in myotubes established from type 2 diabetic subjects

    DEFF Research Database (Denmark)

    Just, Malene; Faergeman, Nils J; Knudsen, Jens;

    2006-01-01

    Accumulation of intramuscular long-chain acyl-CoA esters (LCACoA) has previously in animal and human models been suggested to play an important role in lipid induced insulin resistance. The aim of this study was to examine whether myotubes established from type 2 diabetic (T2D) subjects and lean ...

  7. ETFDH mutations as a major cause of riboflavin-responsive multiple acyl-CoA dehydrogenation deficiency

    DEFF Research Database (Denmark)

    Olsen, Rikke K J; Olpin, Simon E; Andresen, Brage S;

    2007-01-01

    Multiple acyl-CoA dehydrogenation deficiency (MADD) is a disorder of fatty acid, amino acid and choline metabolism that can result from defects in two flavoproteins, electron transfer flavoprotein (ETF) or ETF: ubiquinone oxidoreductase (ETF:QO). Some patients respond to pharmacological doses...

  8. Handling of human short-chain acyl-CoA dehydrogenase (SCAD) variant proteins in transgenic mice

    DEFF Research Database (Denmark)

    Kragh, Peter M; Pedersen, Christina B; Schmidt, Stine P;

    2007-01-01

    Abstract To investigate the in vivo handling of human short-chain acyl-CoA dehydrogenase (SCAD) variant proteins, three transgenic mouse lines were produced by pronuclear injection of cDNA encoding the wild-type, hSCAD-wt, and two disease causing folding variants hSCAD-319C > T and hSCAD-625G > A...

  9. DNA-based prenatal diagnosis for severe and variant forms of multiple acyl-CoA dehydrogenation deficiency

    DEFF Research Database (Denmark)

    Olsen, Rikke K J; Andresen, Brage S; Christensen, Ernst;

    2005-01-01

    OBJECTIVES: Multiple acyl-CoA dehydrogenation deficiency (MADD) is a clinically heterogeneous disorder of mitochondrial fatty acid, amino acid, and choline oxidation due to mutations in the genes encoding electron transfer flavoprotein (ETF) or ETF ubiquinone oxidoreductase (ETFQO). So far...

  10. Indium triflate in 1-isobutyl-3-methylimidazolium dihydrogenphosphate: an efficient and green catalytic system for Friedel-Crafts acylation

    DEFF Research Database (Denmark)

    Tran, Phuong Hoang; Hoang, Huy Manh; Chau, Duy-Khiem Nguyen;

    2015-01-01

    Indium triflate in the ionic liquid, 1-isobutyl-3-methylimidazolium dihydrogen phosphate ([i-BMIM]H2PO4), was found to show enhanced catalytic activity in the Friedel–Crafts acylation of various aromatic compounds with acid anhydrides. The catalytic system was easily recovered and reused without ...

  11. An efficient and green synthesis of 1-indanone and 1-tetralone via intramolecular Friedel-Crafts acylation reaction

    DEFF Research Database (Denmark)

    Tran, Phuong Hoang; Huynh, Vy Hieu; Hansen, Poul Erik;

    2015-01-01

    Metal-triflate-catalyzed intramolecular Friedel–Crafts acylation of 3-arylpropanoic and 4-arylbutanoic acids in triflate-anion ionic liquids under monomodal microwave irradiation is reported. The environmentally benign synthetic procedure allows the formation of cyclic ketones in good yields with...

  12. Production of N-acyl-L-homoserine lactones by P. aeruginosa isolates from chronic lung infections associated with cystic fibrosis

    DEFF Research Database (Denmark)

    Geisenberger, O; Givskov, M; Riedel, K;

    2000-01-01

    The N-acyl-L-homoserine lactones (AHLs) produced by sequential Pseudomonas aeruginosa isolates from chronically infected patients with cystic fibrosis were analyzed by thin-layer chromatography. It is demonstrated that both the amounts and the types of molecules synthesized by isolates from...

  13. Abnormal mitochondrial bioenergetics and heart rate dysfunction in mice lacking very-long-chain acyl-CoA dehydrogenase

    NARCIS (Netherlands)

    Exil, VJ; Gardner, CD; Rottman, JN; Sims, H; Bartelds, B; Khuchua, Z; Sindhal, R; Ni, GM; Strauss, AW

    2006-01-01

    Mitochondrial very-long-chain acyl-CoA dehydrogenase ( VLCAD) deficiency is associated with severe hypoglycemia, cardiac dysfunction, and sudden death in neonates and children. Sudden death is common, but the underlying mechanisms are not fully understood. We report on a mouse model of VLCAD deficie

  14. Securiosides A and B, novel acylated triterpene bisdesmosides with selective cytotoxic activity against M-CSF-stimulated macrophages.

    Science.gov (United States)

    Kuroda, M; Mimaki, Y; Sashida, Y; Kitahara, M; Yamazaki, M; Yui, S

    2001-02-12

    We report the discovery of securiosides A (1) and B (2), novel acylated triterpene bisdesmosides, isolated from the roots of Securidaca inappendiculata. Securiosides A and B showed potent selective cytotoxic activity against M-CSF-stimulated macrophages and were suggested to have potential as new agents for the treatment of inflammatory diseases such as RA and atherosclerosis. PMID:11212113

  15. Kinetics of enzyme acylation and deacylation in the penicillin acylase-catalyzed synthesis of beta-lactam antibiotics

    NARCIS (Netherlands)

    Alkema, WBL; de Vries, E; Floris, R; Janssen, DB

    2003-01-01

    Penicillin acylase catalyses the hydrolysis and synthesis of semisynthetic beta-lactam antibiotics via formation of a covalent acyl-enzyme intermediate. The kinetic and mechanistic aspects of these reactions were studied. Stopped-flow experiments with the penicillin and ampicillin analogues 2-nitro-

  16. Deficiency of acyl-CoA: Dihydroxyacetone phosphate acyltransferase in patients with Zellweger (cerebro-hepato-renal) syndrome

    NARCIS (Netherlands)

    Bosch, H. van den; Schutgens, R.B.H.; Romeyn, G.J.; Wanders, R.J.A.; Schrakamp, G.; Heymans, H.S.A.

    1984-01-01

    We have recently reported on plasmalogen deficiency in tissues and fibroblasts from patients with Zellweger syndrome. In this paper we have analyzed the activity of the first enzyme in the pathway leading to plasmalogen biosynthesis, i.e. acyl-CoA: dihydroxyacetone phosphate acyltransferase in liver

  17. 2',3'-cyclic nucleotide-3'-phosphodiesterase in the central nervous system is fatty-acylated by thioester linkage.

    Science.gov (United States)

    Agrawal, H C; Sprinkle, T J; Agrawal, D

    1990-07-15

    2',3'-Cyclic nucleotide-3'-phosphodiesterase (CNP1 and CNP2 with Mr of 46,000 and 48,000, respectively) is the major enzyme of central nervous system myelin. It is associated with oligodendroglial plasma membrane and uncompacted myelin (myelin-like fraction), which are in contact with glial cytoplasm. Proteins of the myelin-like fraction were labeled with [3H]palmitic acid in brain slices from 17-day-old rats and immunoprecipitated with anti-CNP antiserum. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and fluorography of immunoprecipitated material revealed intense acylation of CNP1 and CNP2, and radioactivity was released by hydroxylamine. Palmitic acid was covalently bound to CNP because radioactivity was not removed by extraction of immunoprecipitated CNP with organic solvent or by boiling in sodium dodecyl sulfate and dithiothreitol. However, treatment of immunoprecipitated CNP with (a) hydroxylamine-released palmitohydroxamate and palmitic acid, (b) sodium borohydride-released hexadecanol, and (c) methanolic-KOH-released methyl palmitate. Synthesis, acylation, or transport of CNP was not affected by monensin or colchicine. However, acylation of CNP was inhibited 24-32% by cycloheximide. These results provide conclusive evidence that CNP1 and CNP2 are fatty acid acylated with palmitate through a thioester linkage and is posttranslationally modified sometime after synthesis. PMID:2164018

  18. Intramolecular Acylation of Aryl- and Aroyl-Aliphatic Acids by the Action of Pyrophosphoryl Chloride and Phosphorus Oxychloride

    Directory of Open Access Journals (Sweden)

    Saleh Rayyan

    2001-03-01

    Full Text Available Both pyrophosphoryl chloride and phosphorus oxychloride react with aryl aliphatic acids to form mixed anhydrides which undergo intramolecular acylation to afford cyclic ketones without the addition of a Friedel-Crafts catalyst. Aryl and aroylbenzoic acids could be cyclized to the corresponding anthrones and anthraquinones respectively.

  19. Evaluation of Effect of Microwave Irradiation on Syntheses and Reactions of Some New 3-Acyl-methylchromones

    Directory of Open Access Journals (Sweden)

    Mikulas Furdik

    1998-03-01

    Full Text Available The 3-Acyl-2-R-methylchromones (R = H, ArO, C6H4(CO2N were prepared in good yields by different methods from 2-hydroxyaroylacetone derivatives. Some subsequent reactions of these compounds with hydroxylamine and 3-formylchromones are described. The effect of microwave irradation on some condensation reactions was studied.

  20. The molecular basis of medium-chain acyl-CoA dehydrogenase (MCAD) deficiency in compound heterozygous patients

    DEFF Research Database (Denmark)

    Andresen, B S; Bross, P; Udvari, S;

    1997-01-01

    Medium-chain acyl-CoA dehydrogenase (MCAD) deficiency is the most commonly recognized defect of mitochondrial beta-oxidation. It is potentially fatal, but shows a wide clinical spectrum. The aim of the present study was to investigate whether any correlation exists between MCAD genotype and disea...

  1. Characterization of a small acyl-CoA-binding protein (ACBP) from Helianthus annuus L. and its binding affinities.

    Science.gov (United States)

    Aznar-Moreno, Jose A; Venegas-Calerón, Mónica; Du, Zhi-Yan; Garcés, Rafael; Tanner, Julian A; Chye, Mee-Len; Martínez-Force, Enrique; Salas, Joaquín J

    2016-05-01

    Acyl-CoA-binding proteins (ACBPs) bind to acyl-CoA esters and promote their interaction with other proteins, lipids and cell structures. Small class I ACBPs have been identified in different plants, such as Arabidopsis thaliana (AtACBP6), Brassica napus (BnACBP) and Oryza sativa (OsACBP1, OsACBP2, OsACBP3), and they are capable of binding to different acyl-CoA esters and phospholipids. Here we characterize HaACBP6, a class I ACBP expressed in sunflower (Helianthus annuus) tissues, studying the specificity of its corresponding recombinant HaACBP6 protein towards various acyl-CoA esters and phospholipids in vitro, particularly using isothermal titration calorimetry and protein phospholipid binding assays. This protein binds with high affinity to de novo synthetized derivatives palmitoly-CoA, stearoyl-CoA and oleoyl-CoA (Kd 0.29, 0.14 and 0.15 μM respectively). On the contrary, it showed lower affinity towards linoleoyl-CoA (Kd 5.6 μM). Moreover, rHaACBP6 binds to different phosphatidylcholine species (dipalmitoyl-PC, dioleoyl-PC and dilinoleoyl-PC), yet it displays no affinity towards other phospholipids like lyso-PC, phosphatidic acid and lysophosphatidic acid derivatives. In the light of these results, the possible involvement of this protein in sunflower oil synthesis is considered. PMID:26938582

  2. Deficiency of cardiac Acyl-CoA synthetase-1 induces diastolic dysfunction, but pathologic hypertrophy is reversed by rapamycin

    DEFF Research Database (Denmark)

    Paul, David S; Grevengoed, Trisha J; Pascual, Florencia;

    2014-01-01

    In mice with temporally-induced cardiac-specific deficiency of acyl-CoA synthetase-1 (Acsl1(H-/-)), the heart is unable to oxidize long-chain fatty acids and relies primarily on glucose for energy. These metabolic changes result in the development of both a spontaneous cardiac hypertrophy and inc...

  3. The binding versatility of plant acyl-CoA-binding proteins and their significance in lipid metabolism.

    Science.gov (United States)

    Lung, Shiu-Cheung; Chye, Mee-Len

    2016-09-01

    Acyl-CoA esters are the activated form of fatty acids and play important roles in lipid metabolism and the regulation of cell functions. They are bound and transported by nonenzymic proteins such as the acyl-CoA-binding proteins (ACBPs). Although plant ACBPs were so named by virtue of amino acid homology to existing yeast and mammalian counterparts, recent studies revealed that ligand specificities of plant ACBPs are not restricted to acyl-CoA esters. Arabidopsis and rice ACBPs also interact with phospholipids, and their affinities to different acyl-CoA species and phospholipid classes vary amongst isoforms. Their ligands also include heavy metals. Interactors of plant ACBPs are further diversified due to the evolution of protein-protein interacting domains. This review summarizes our current understanding of plant ACBPs with a focus on their binding versatility. Their broad ligand range is of paramount significance in serving a multitude of functions during development and stress responses as discussed herein. This article is part of a Special Issue entitled: Plant Lipid Biology edited by Kent D. Chapman and Ivo Feussner. PMID:26747650

  4. Structural characterization and comparison of three acyl-carrier-protein synthases from pathogenic bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Halavaty, Andrei S. [Center for Structural Genomics of Infectious Diseases, (United States); Northwestern University, Chicago, IL 60611 (United States); Kim, Youngchang [Center for Structural Genomics of Infectious Diseases, (United States); Argonne National Laboratory, Argonne, IL 60439 (United States); University of Chicago, Chicago, IL 60637 (United States); Minasov, George; Shuvalova, Ludmilla; Dubrovska, Ievgeniia; Winsor, James [Center for Structural Genomics of Infectious Diseases, (United States); Northwestern University, Chicago, IL 60611 (United States); Zhou, Min [Center for Structural Genomics of Infectious Diseases, (United States); Argonne National Laboratory, Argonne, IL 60439 (United States); University of Chicago, Chicago, IL 60637 (United States); Onopriyenko, Olena; Skarina, Tatiana [Center for Structural Genomics of Infectious Diseases, (United States); University of Toronto, Toronto, Ontario M5G 1L6 (Canada); Papazisi, Leka; Kwon, Keehwan; Peterson, Scott N. [Center for Structural Genomics of Infectious Diseases, (United States); J. Craig Venter Institute, Rockville, MD 20850 (United States); Joachimiak, Andrzej [Center for Structural Genomics of Infectious Diseases, (United States); Argonne National Laboratory, Argonne, IL 60439 (United States); University of Chicago, Chicago, IL 60637 (United States); Savchenko, Alexei [Center for Structural Genomics of Infectious Diseases, (United States); University of Toronto, Toronto, Ontario M5G 1L6 (Canada); Anderson, Wayne F., E-mail: wf-anderson@northwestern.edu [Center for Structural Genomics of Infectious Diseases, (United States); Northwestern University, Chicago, IL 60611 (United States)

    2012-10-01

    The structural characterization of acyl-carrier-protein synthase (AcpS) from three different pathogenic microorganisms is reported. One interesting finding of the present work is a crystal artifact related to the activity of the enzyme, which fortuitously represents an opportunity for a strategy to design a potential inhibitor of a pathogenic AcpS. Some bacterial type II fatty-acid synthesis (FAS II) enzymes have been shown to be important candidates for drug discovery. The scientific and medical quest for new FAS II protein targets continues to stimulate research in this field. One of the possible additional candidates is the acyl-carrier-protein synthase (AcpS) enzyme. Its holo form post-translationally modifies the apo form of an acyl carrier protein (ACP), which assures the constant delivery of thioester intermediates to the discrete enzymes of FAS II. At the Center for Structural Genomics of Infectious Diseases (CSGID), AcpSs from Staphylococcus aureus (AcpS{sub SA}), Vibrio cholerae (AcpS{sub VC}) and Bacillus anthracis (AcpS{sub BA}) have been structurally characterized in their apo, holo and product-bound forms, respectively. The structure of AcpS{sub BA} is emphasized because of the two 3′, 5′-adenosine diphosphate (3′, 5′-ADP) product molecules that are found in each of the three coenzyme A (CoA) binding sites of the trimeric protein. One 3′, 5′-ADP is bound as the 3′, 5′-ADP part of CoA in the known structures of the CoA–AcpS and 3′, 5′-ADP–AcpS binary complexes. The position of the second 3′, 5′-ADP has never been described before. It is in close proximity to the first 3′, 5′-ADP and the ACP-binding site. The coordination of two ADPs in AcpS{sub BA} may possibly be exploited for the design of AcpS inhibitors that can block binding of both CoA and ACP.

  5. Outer automorphism groups of certain 1-relator groups

    Institute of Scientific and Technical Information of China (English)

    KIM; Goansu

    2010-01-01

    Grossman first showed that outer automorphism groups of 1-relator groups given by orientable surface groups are residually finite,whence mapping class groups of orientable surfaces are residually finite.Allenby,Kim and Tang showed that outer automorphism groups of cyclically pinched 1-relator groups are residually finite,whence mapping class groups of orientable and non-orientable surfaces are residually finite.In this paper we show that outer automorphism groups of certain conjugacy separable 1-relator groups are residually finite.

  6. Distribution and Spectroscopy of Green Fluorescent Protein and Acyl-CoA: Cholesterol Acytransferase in Sf21 Insect Cells

    Science.gov (United States)

    Richmond, R. C.; Mahtani, H.; Lu, X.; Chang, T. Y.; Malak, H.; Rose, M. Franklin (Technical Monitor)

    2001-01-01

    Acyl-CoA: cholesterol acyltransferase (ACAT) is thought to significantly participate in the pathway of cholesterol esterification that underlies the pathology of artherosclerosis. This enzyme is a membrane protein known to be preferentially bound within the endoplasmic reticulum of mammalian cells, from which location it esterifies cholesterol derived from low density lipoprotein. Cultures of insect cells were separately infected with baculovirus containing the gene for green fluroescent protein (GFP) and with baculovirus containing tandem genes for GFP and ACAT. These infected cultures expressed GFP and the fusion protein GCAT, respectively, with maximum expression occurring on the fourth day after infection. Extraction of GFP- and of GCAT-expressing cells with urea and detergent resulted in recovery of fluorescent protein in aqueous solution. Fluorescence spectra at neutral pH were identical for both GFP and GCAT extracts in aqueous solution, indicating unperturbed tertiary structure for the GFP moiety within GCAT. In a cholesterol esterification assay, GCAT demonstrated ACAT activity, but with less efficiency compared to native ACAT. It was hypothesized that the membrane protein ACAT would lead to differences in localization of GCAT compared to GFP within the respective expressing insect cells. The GFP marker directly and also within the fusion protein GCAT was accordingly used as the intracellular probe that was fluorescently analyzed by the new biophotonics technique of hyperspectral imaging. In that technique, fluorescence imaging was obtained from two dimensional arrays of cells, and regions of interest from within those images were then retrospectively analyzed for the emission spectra that comprises the image. Results of hyperspectral imaging of insect cells on day 4 postinfection showed that GCAT was preferentially localized to the cytoplasm of these cells compared to GFP. Furthermore, the emission spectra obtained for the localized GCAT displayed a peak

  7. Structure of YciA from Haemophilus influenzae (HI0827), a Hexameric Broad Specificity Acyl-Coenzyme A Thioesterase

    Energy Technology Data Exchange (ETDEWEB)

    Willis, Mark A.; Zhuang, Zhihao; Song, Feng; Howard, Andrew; Dunaway-Mariano, Debra; Herzberg, Osnat (UNM); (IIT); (UMBI)

    2008-04-02

    The crystal structure of HI0827 from Haemophilus influenzae Rd KW20, initially annotated 'hypothetical protein' in sequence databases, exhibits an acyl-coenzyme A (acyl-CoA) thioesterase 'hot dog' fold with a trimer of dimers oligomeric association, a novel assembly for this enzyme family. In studies described in the preceding paper [Zhuang, Z., Song, F., Zhao, H., Li, L., Cao, J., Eisenstein, E., Herzberg, O., and Dunaway-Mariano, D. (2008) Biochemistry 47, 2789-2796], HI0827 is shown to be an acyl-CoA thioesterase that acts on a wide range of acyl-CoA compounds. Two substrate binding sites are located across the dimer interface. The binding sites are occupied by two CoA molecules, one with full occupancy and the second only partially occupied. The CoA molecules, acquired from HI0827-expressing Escherichia coli cells, remained tightly bound to the enzyme through the protein purification steps. The difference in CoA occupancies indicates a different substrate affinity for each of the binding sites, which in turn implies that the enzyme might be subject to allosteric regulation. Mutagenesis studies have shown that the replacement of the putative catalytic carboxylate Asp44 with an alanine residue abolishes activity. The impact of this mutation is seen in the crystal structure of D44A HI0827. Whereas the overall fold and assembly of the mutant protein are the same as those of the wild-type enzyme, the CoA ligands are absent. The dimer interface is perturbed, and the channel that accommodates the thioester acyl chain is more open and wider than that observed in the wild-type enzyme. A model of intact substrate bound to wild-type HI0827 provides a structural rationale for the broad substrate range.

  8. Pantoea sp. isolated from tropical fresh water exhibiting N-acyl homoserine lactone production.

    Science.gov (United States)

    Tan, Wen-Si; Muhamad Yunos, Nina Yusrina; Tan, Pui-Wan; Mohamad, Nur Izzati; Adrian, Tan-Guan-Sheng; Yin, Wai-Fong; Chan, Kok-Gan

    2014-01-01

    N-Acyl homoserine lactone (AHL) serves as signaling molecule for quorum sensing (QS) in Gram-negative bacteria to regulate various physiological activities including pathogenicity. With the aim of isolating freshwater-borne bacteria that can cause outbreak of disease in plants and portrayed QS properties, environmental water sampling was conducted. Here we report the preliminary screening of AHL production using Chromobacterium violaceum CV026 and Escherichia coli [pSB401] as AHL biosensors. The 16S rDNA gene sequence of isolate M009 showed the highest sequence similarity to Pantoea stewartii S9-116, which is a plant pathogen. The isolated Pantoea sp. was confirmed to produce N-3-oxohexanoyl-L-HSL (3-oxo-C6-HSL) through analysis of high resolution mass tandem mass spectrometry. PMID:25197715

  9. Pantoea sp. Isolated from Tropical Fresh Water Exhibiting N-Acyl Homoserine Lactone Production

    Directory of Open Access Journals (Sweden)

    Wen-Si Tan

    2014-01-01

    Full Text Available N-Acyl homoserine lactone (AHL serves as signaling molecule for quorum sensing (QS in Gram-negative bacteria to regulate various physiological activities including pathogenicity. With the aim of isolating freshwater-borne bacteria that can cause outbreak of disease in plants and portrayed QS properties, environmental water sampling was conducted. Here we report the preliminary screening of AHL production using Chromobacterium violaceum CV026 and Escherichia coli [pSB401] as AHL biosensors. The 16S rDNA gene sequence of isolate M009 showed the highest sequence similarity to Pantoea stewartii S9-116, which is a plant pathogen. The isolated Pantoea sp. was confirmed to produce N-3-oxohexanoyl-L-HSL (3-oxo-C6-HSL through analysis of high resolution mass tandem mass spectrometry.

  10. Hydrophobic cellulose films with excellent strength and toughness via ball milling activated acylation of microfibrillated cellulose.

    Science.gov (United States)

    Deng, Sha; Huang, Rui; Zhou, Mi; Chen, Feng; Fu, Qiang

    2016-12-10

    Cellulose films with excellent mechanical strength are of interest to many researchers, but unfortunately they often lack the ductility and water resistance. This work demonstrates an efficient and easily industrialized method for hydrophobic cellulose films made of modified microfibrillated cellulose (MFC). Prior to film fabrication, the simultaneous exfoliation and acylation of MFC was achieved through the synergetic effect of mechanical and chemical actions generated from ball milling in the presence of hexanoyl chloride. Largely enhanced tensile strength and elongation at break have been achieved (4.98MPa, 4.37% for original MFC films, 140MPa, 21.3% for modified ones). Due to hydrophobicity and compact structure, modified films show excellent water resistance and decreased water vapor permeability. Moreover, optical performance of modified films is also improved compared with the original MFC films. Our work can largely expand the application of this biodegradable resource and ultimately reduce the need for petroleum-based plastics. PMID:27577904

  11. A new acylated flavonoid tetraglycoside with anti-inflammatory activity from Tipuana tipu leaves.

    Science.gov (United States)

    Amen, Yhiya M; Marzouk, Amani M; Zaghloul, Mona G; Afifi, Mohamed S

    2015-01-01

    A new acylated kaempferol glycoside, kaempferol 3-O-α-l-rhamnopyranosyl-(1 → 6)-O-[β-d-glucopyranosyl-(1 → 2)-4-O-acetyl-α-l-rhamnopyranosyl-(1 → 2)]-β-d-galactopyranoside, has been isolated from the leaves of Tipuana tipu (Benth.) Lillo growing in Egypt, along with three known flavonol glycosides, kaempferol 3-O-rutinoside, quercetin 3-O-rutinoside (rutin) and kaempferol 3-O-[α-l-rhamnopyranosyl-(1 → 6)]-[α-l-rhamnopyranosyl-(1 → 2]-β-d-glucopyranoside. Structure elucidation was achieved through different spectroscopic methods. Structure relationship with anti-inflammatory activity using carrageenin-induced rat paw oedema model is discussed.

  12. Pseudomonas cremoricolorata Strain ND07 Produces N-acyl Homoserine Lactones as Quorum Sensing Molecules

    Directory of Open Access Journals (Sweden)

    Nina Yusrina Muhamad Yunos

    2014-06-01

    Full Text Available Quorum sensing (QS is a bacterial cell-to-cell communication system controlling QS-mediated genes which is synchronized with the population density. The regulation of specific gene activity is dependent on the signaling molecules produced, namely N-acyl homoserine lactones (AHLs. We report here the identification and characterization of AHLs produced by bacterial strain ND07 isolated from a Malaysian fresh water sample. Molecular identification showed that strain ND07 is clustered closely to Pseudomonas cremoricolorata. Spent culture supernatant extract of P. cremoricolorata strain ND07 activated the AHL biosensor Chromobacterium violaceum CV026. Using high resolution triple quadrupole liquid chromatography-mass spectrometry, it was confirmed that P. cremoricolorata strain ND07 produced N-octanoyl-l-homoserine lactone (C8-HSL and N-decanoyl-l-homoserine lactone (C10-HSL. To the best of our knowledge, this is the first documentation on the production of C10-HSL in P. cremoricolorata strain ND07.

  13. An Acylated Kaempferol Glycoside from Flowers of Foeniculum vulgare and F. Dulce

    Directory of Open Access Journals (Sweden)

    Shahera M. Ezzat

    2002-02-01

    Full Text Available An acylated kaempferol glycoside, namely kaempferol-3-O-α-L-(2”,3”-di-E-pcoumaroyl-rhamnoside (1 was isolated from the flowers of Foeniculum vulgare Mill. and F. dulce DC. It is thus isolated for the first time from family Apiaceae. In addition, the different organs of both plants afforded six flavonoid glycosides - namely afzelin (kaempferol-3-O-α-L-rhamnoside (2, quercitrin (3, isorhamnetin-3-O-β-D-glucoside (4, isoquercitrin (5, rutin (6, and miquelianin (quercetin-3-O-β-D-glucuronide (7. Structure elucidation of the above mentioned flavonoids was achieved by UV, 1H- and 13C-NMR, 1H-1H COSY, HMQC and EI-MS.

  14. Dietary acylated starch improves performance and gut health in necrotic enteritis challenged broilers.

    Science.gov (United States)

    M'Sadeq, Shawkat A; Wu, Shu-Biao; Swick, Robert A; Choct, Mingan

    2015-10-01

    Resistant starch has been reported to act as a protective agent against pathogenic organisms in the gut and to encourage the proliferation of beneficial organisms. This study examined the efficacy of acetylated high amylose maize starch (SA) and butyralated high-amylose maize starch (SB) in reducing the severity of necrotic enteritis (NE) in broilers under experimental challenge. A total of 720 one-day-old male Ross 308 chicks were assigned to 48 floor pens with a 2 × 4 factorial arrangement of treatments. Factors were a) challenge: no or yes; and b) feed additive: control, antibiotics (AB), SA, or SB. Birds were challenged with Eimeria and C. perfringens according to a previously reported protocol. On d 24 and 35, challenged birds had lower (P enteritis. Depending on the acid used, starch acylation also offers a degree of specificity in short chain fatty acid (SCFA) delivery to the lower intestinal tract which improves gut health.

  15. Preparation of acetylsalicylic acid-acylated chitosan as a novel polymeric drug for drug controlled release.

    Science.gov (United States)

    Liu, Changkun; Wu, Yiguang; Zhao, Liyan; Huang, Xinzheng

    2015-01-01

    The acetylsalicylic acid-acylated chitosan (ASACTS) with high degree of substitution (DS) was successfully synthesized, and characterized with FTIR, (1)H NMR and elemental analysis methods. The optimum synthesis conditions were obtained which gave the highest DS (about 60%) for ASACTS. Its drug release experiments were carried out in simulated gastric and intestine fluids. The results show that the drugs in the form of acetylsalicylic acid (ASA) and salicylic acid (SA) were released in a controlled manner from ASACTS only in simulated gastric fluid. The release profile can be best fitted with logistic and Weibull model. The research results reveal that ASACTS can be a potential polymeric drug for the controlled release of ASA and SA in the targeted gastric environment.

  16. Understanding the control of acyl flux through the lipid metabolic network of plant oil biosynthesis.

    Science.gov (United States)

    Bates, Philip D

    2016-09-01

    Plant oil biosynthesis involves a complex metabolic network with multiple subcellular compartments, parallel pathways, cycles, and pathways that have a dual function to produce essential membrane lipids and triacylglycerol. Modern molecular biology techniques provide tools to alter plant oil compositions through bioengineering, however with few exceptions the final composition of triacylglycerol cannot be predicted. One reason for limited success in oilseed bioengineering is the inadequate understanding of how to control the flux of fatty acids through various fatty acid modification, and triacylglycerol assembly pathways of the lipid metabolic network. This review focuses on the mechanisms of acyl flux through the lipid metabolic network, and highlights where uncertainty resides in our understanding of seed oil biosynthesis. This article is part of a Special Issue entitled: Plant Lipid Biology edited by Kent D. Chapman and Ivo Feussner. PMID:27003249

  17. Medium-Chain Acyl-CoA Dehydrogenase Deficiency in Gene-Targeted Mice.

    Directory of Open Access Journals (Sweden)

    2005-08-01

    Full Text Available Medium-chain acyl-CoA dehydrogenase (MCAD deficiency is the most common inherited disorder of mitochondrial fatty acid beta-oxidation in humans. To better understand the pathogenesis of this disease, we developed a mouse model for MCAD deficiency (MCAD by gene targeting in embryonic stem (ES cells. The MCAD mice developed an organic aciduria and fatty liver, and showed profound cold intolerance at 4 degrees C with prior fasting. The sporadic cardiac lesions seen in MCAD mice have not been reported in human MCAD patients. There was significant neonatal mortality of MCAD pups demonstrating similarities to patterns of clinical episodes and mortality in MCAD-deficient patients. The MCAD-deficient mouse reproduced important aspects of human MCAD deficiency and is a valuable model for further analysis of the roles of fatty acid oxidation and pathogenesis of human diseases involving fatty acid oxidation.

  18. Acylated delphinidin glycosides from violet and violet-blue flowers of Clematis cultivars and their coloration.

    Science.gov (United States)

    Sakaguchi, Keisuke; Kitajima, Junichi; Iwashina, Tsukasa

    2013-11-01

    Three new acylated delphinidin glycosides, delphinidin 3-O-beta-[(2"-trans-caffeoylglucopyranosyl)-(1 --> 2)-(6"-succinylgalactopyranoside)]-7-O-beta-glucopyranoside (1), delphinidin 3-O-beta-[(2"-trans-caffeoylglucopyranosyl)-(1 --> 2)-(6"-trans-caffeoyl-tartaroyl-malonylgalactopyranoside)]-7-O-beta-glucopyranoside (2), and delphinidin 3-O-beta-[(2"-trans-caffeoylglucopyranosyl)-(1 --> 2)-(6"-trans-caffeoyl-tartaroyl-malonylgalactopyranoside)]-3'-O-beta-glucuronopyranoside (3), were isolated from the violet and violet-blue sepals of Clematis cultivars 'Jackmanii Superba' and 'Fujimusume'. The chemical structures of the isolated anthocyanins were determined by LC-MS, characterization of hydrolyzates, and UV, 1H and 13C NMR spectroscopy. The visible absorption spectra of these anthocyanins were compared with those of fresh sepals and crude extracts in pH 5.1 buffer solution. In addition, the co-pigment effect with some kaempferol glycosides and caffeoylglucose was examined. PMID:24427942

  19. Thermodynamically based solvent design for enzymatic saccharide acylation with hydroxycinnamic acids in non-conventional media

    DEFF Research Database (Denmark)

    Zeuner, Birgitte; Kontogeorgis, Georgios; Riisager, Anders;

    2012-01-01

    Enzyme-catalyzed synthesis has been widely studied with lipases (EC 3.1.1.3), but feruloyl esterases (FAEs; EC 3.1.1.73) may provide advantages such as higher substrate affinity and regioselectivity in the synthesis of hydroxycinnamate saccharide esters. These compounds are interesting because...... as well as other enzymatic hydroxycinnamate acylations in ionic liquid systems. The choice of solvent system is highly decisive for enzyme stability, selectivity, and reaction yields in these synthesis reactions. To increase the understanding of the reaction environment and to facilitate solvent screening......-free microemulsions of a hydrocarbon, a polar alcohol, and water are interesting solvent systems because they accommodate different substrate and product solubilities and maintain enzyme stability. Ionic liquids may provide advantages as solvents in terms of increased substrate and product solubility, higher...

  20. Biofilm activity and sludge characteristics affected by exogenous N-acyl homoserine lactones in biofilm reactors.

    Science.gov (United States)

    Hu, Huizhi; He, Junguo; Liu, Jian; Yu, Huarong; Zhang, Jie

    2016-07-01

    This study verified the effect of N-acyl homoserine lactone (AHL) concentrations on mature biofilm systems. Three concentrations of an AHL mixture were used in the batch test. Introducing of 5nM AHLs significantly increased biofilm activity and increased sludge characteristics, which resulted in better pollutant removal performance, whereas exogenous 50nM and 500nM AHLs limited pollutant removal, especially COD and nitrogen removal. To further identify how exogenous signal molecular affects biofilm system nitrogen removal, analyzing of nitrifying bacteria through real-time polymerase chain reaction (RT-PCR) revealed that these additional signal molecules affect nitrifying to total bacteria ratio. In addition, the running state of the system was stable during 15days of operation without an AHL dose, which suggests that the changes in the system due to AHL are irreversible. PMID:27030953

  1. SYNTHESIS OF 1,2-ACEANTHRYLENEDIONE THROUGH ACYLATION OF ANTHRACENE WITH OXALYL CHLORIDE

    Institute of Scientific and Technical Information of China (English)

    ZHANG Chunyan; CHEN Min; YU Long; JIANG Deli YAN Yongsheng

    2007-01-01

    Acylation of anthracene and oxalyl chloride in the presence of anhydrous AlCl3 was investigated. Pure 1,2-aceanthrylenedione, which is used as new functional macromolecule, was prepared by extraction and recrystallation. The structure of 1,2-aceanthrylenedione was identified by measure of melting point, GC/MS, FTIR and 1HNMR analyses. The influences of various parameters,such as solvent, dosage of catalyst, molar ratio of anthracene to oxalyl chloride, reaction temperature, and reaction time were studied. The anhydrous AlCl3 was found to catalyze the reaction with high yeild and good selectivity. When the reaction temperature is 303K, reaction time is 5h and molar ratio of anthracene to oxalyl chloride is 1:2, the yield and selectivity of 1,2-aceanthrylenedione is 83.8 % and 92.3% respectively.

  2. SYNTHESIS OF 1,2-ACEANTHRYLENEDIONE THROUGH ACYLATION OF ANTHRACENE WITH OXALYL CHLORIDE

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Acylation of anthracene and oxalyl chloride in the presence of anhydrous AlCl3 was investigated. Pure 1,2-aceanthrylenedione, which is used as new functional macromolecule, was prepared by extraction and recrystallation. The structure of 1,2-aceanthrylenedione was identified by measure of melting point, GC/MS, FTIR and 1HNMR analyses. The influences of various parameters, such as solvent, dosage of catalyst, molar ratio of anthracene to oxalyl chloride, reaction temperature, and reaction time were studied. The anhydrous AlCl3 was found to catalyze the reaction with high yeild and good selectivity. When the reaction temperature is 303K, reaction time is 5h and molar ratio of anthracene to oxalyl chloride is 1:2, the yield and selectivity of 1,2-aceanthrylenedione is 83.8 % and 92.3% respectively.

  3. N-Acyl Dehydrotyrosines, Tyrosinase Inhibitors from the Marine Bacterium Thalassotalea sp. PP2-459.

    Science.gov (United States)

    Deering, Robert W; Chen, Jianwei; Sun, Jiadong; Ma, Hang; Dubert, Javier; Barja, Juan L; Seeram, Navindra P; Wang, Hong; Rowley, David C

    2016-02-26

    Thalassotalic acids A-C and thalassotalamides A and B are new N-acyl dehydrotyrosine derivatives produced by Thalassotalea sp. PP2-459, a Gram-negative bacterium isolated from a marine bivalve aquaculture facility. The structures were elucidated via a combination of spectroscopic analyses emphasizing two-dimensional NMR and high-resolution mass spectrometric data. Thalassotalic acid A (1) displays in vitro inhibition of the enzyme tyrosinase with an IC50 value (130 μM) that compares favorably to the commercially used control compounds kojic acid (46 μM) and arbutin (100 μM). These are the first natural products reported from a bacterium belonging to the genus Thalassotalea. PMID:26824128

  4. Prolonged QTc interval in association with medium-chain acyl-coenzyme A dehydrogenase deficiency.

    Science.gov (United States)

    Wiles, Jason R; Leslie, Nancy; Knilans, Timothy K; Akinbi, Henry

    2014-06-01

    Medium-chain acyl-coenzyme A dehydrogenase (MCAD) deficiency is the most common disorder of mitochondrial fatty acid oxidation. We report a term male infant who presented at 3 days of age with hypoglycemia, compensated metabolic acidosis, hypocalcemia, and prolonged QTc interval. Pregnancy was complicated by maternal premature atrial contractions and premature ventricular contractions. Prolongation of the QTc interval resolved after correction of metabolic derangements. The newborn screen was suggestive for MCAD deficiency, a diagnosis that was confirmed on genetic analysis that showed homozygosity for the disease-associated missense A985G mutation in the ACADM gene. This is the first report of acquired prolonged QTc in a neonate with MCAD deficiency, and it suggests that MCAD deficiency should be considered in the differential diagnoses of acute neonatal illnesses associated with electrocardiographic abnormality. We review the clinical presentation and diagnosis of MCAD deficiency in neonates. PMID:24799540

  5. A group contribution method for estimating the vapour pressures of α-pinene oxidation products

    OpenAIRE

    J. F. Müller; Capouet, M.

    2005-01-01

    A prediction method based on group contribution principles is proposed for estimating the vapour pressure of α-pinene oxidation products. Temperature dependent contributions are provided for the following chemical groups: carbonyl, nitrate, hydroxy, hydroperoxide, acyl peroxy nitrate and acid. On the basis of observed vapour pressure differences between isomers of diols and dinitrates, a simple refinement is introduced in the method, which allows to account for the influence of the subs...

  6. Zomepirac Acyl Glucuronide Is Responsible for Zomepirac-Induced Acute Kidney Injury in Mice.

    Science.gov (United States)

    Iwamura, Atsushi; Watanabe, Katsuhito; Akai, Sho; Nishinosono, Tsubasa; Tsuneyama, Koichi; Oda, Shingo; Kume, Toshiyuki; Yokoi, Tsuyoshi

    2016-07-01

    Glucuronidation, an important phase II metabolic route, is generally considered to be a detoxification pathway. However, acyl glucuronides (AGs) have been implicated in the toxicity of carboxylic acid drugs due to their electrophilic reactivity. Zomepirac (ZP) was withdrawn from the market because of adverse effects such as renal toxicity. Although ZP is mainly metabolized to acyl glucuronide (ZP-AG) by UDP-glucuronosyltransferase, the role of ZP-AG in renal toxicity is unknown. In this study, we established a ZP-induced kidney injury mouse model by pretreatment with tri-o-tolyl phosphate (TOTP), a nonselective esterase inhibitor, and l-buthionine-(S,R)-sulfoximine (BSO), a glutathione synthesis inhibitor. The role of ZP-AG in renal toxicity was investigated using this model. The model showed significant increases in blood urea nitrogen (BUN) and creatinine (CRE), but not alanine aminotransferase. The ZP-AG concentrations were elevated by cotreatment with TOTP in the plasma and liver and especially in the kidney. The ZP-AG concentrations in the kidney correlated with values for BUN and CRE. Upon histopathological examination, vacuoles and infiltration of mononuclear cells were observed in the model mouse. In addition to immune-related responses, oxidative stress markers, such as the glutathione/disulfide glutathione ratio and malondialdehyde levels, were different in the mouse model. The suppression of ZP-induced kidney injury by tempol, an antioxidant agent, suggested the involvement of oxidative stress in ZP-induced kidney injury. This is the first study to demonstrate that AG accumulation in the kidney by TOTP and BSO treatment could explain renal toxicity and to show the in vivo toxicological potential of AGs. PMID:27112166

  7. Stem Cell Separation Technologies

    OpenAIRE

    Zhu, Beili; Murthy, Shashi K

    2013-01-01

    Stem cell therapy and translational stem cell research require large-scale supply of stem cells at high purity and viability, thus leading to the development of stem cell separation technologies. This review covers key technologies being applied to stem cell separation, and also highlights exciting new approaches in this field. First, we will cover conventional separation methods that are commercially available and have been widely adapted. These methods include Fluorescence-activated cell so...

  8. [Separation anxiety. Theoretical considerations].

    Science.gov (United States)

    Blandin, N; Parquet, P J; Bailly, D

    1994-01-01

    The interest in separation anxiety is nowadays increasing: this disorder appearing during childhood may predispose to the occurrence of anxiety disorders (such as panic disorder and agoraphobia) and major depression into adulthood. Psychoanalytic theories differ on the nature of separation anxiety and its place in child development. For some authors, separation anxiety must be understood as resulting from the unconscious internal conflicts inherent in the individuation process and gradual attainment of autonomy. From this point of view, the fear of loss of mother by separation is not regarded as resulting from a real danger. However, Freud considers the primary experience of separation from protecting mother as the prototype situation of anxiety and compares the situations generating fear to separation experiences. For him, anxiety originates from two factors: the physiological fact is initiated at the time of birth but the primary traumatic situation is the separation from mother. This point of view may be compared with behavioral theories. Behavioral theories suggest that separation anxiety may be conditioned or learned from innate fears. In Freud's theory, the primary situation of anxiety resulting from the separation from mother plays a role comparable to innate fears. Grappling with the problem of separation anxiety, Bowlby emphasizes then the importance of the child's attachment to one person (mother or primary caregiver) and the fact that this attachment is instinctive. This point of view, based on the watch of infants, is akin to ethological theories on behaviour of non human primates. Bowlby especially shows that the reactions of infant separated from mother evolve on three stages: the phase of protestation which may constitute the prototype of adulthood anxiety, the phase of desperation which may be the prototype of depression, and the phase of detachment. He emphasizes so the role of early separations in the development of vulnerability to depression

  9. A Historical Cohort Study on the Efficacy of Glucocorticoids and Riboflavin Among Patients with Late-onset Multiple Acyl-CoA Dehydrogenase Deficiency

    Institute of Scientific and Technical Information of China (English)

    Xin-Yi Liu; Zhi-Qiang Wang; Dan-Ni Wang; Min-Ting Lin; Ning Wang

    2016-01-01

    Background:Late-onset multiple acyl-CoA dehydrogenase deficiency (MADD) is the most common type of lipid storage myopathies in China.Most patients with late-onset MADD are well responsive to riboflavin.Up to now,these patients are often treated with glucocorticoids as the first-line drug because they are misdiagnosed as polymyositis without muscle biopsy or gene analysis.Although glucocorticoids seem to improve the fatty acid metabolism of late-onset MADD,the objective evaluation of their rationalization on this disorder and comparison with riboflavin treatment are unknown.Methods:We performed a historical cohort study on the efficacy of the two drugs among 45 patients with late-onset MADD,who were divided into glucocorticoids group and riboflavin group.Detailed clinical information of baseline and 1-month follow-up were collected.Results:After 1-month treatment,a dramatic improvement of muscle strength was found in riboflavin group (P < 0.05).There was no significant difference in muscle enzymes between the two groups.Significantly,the number of patients with full recovery in glucocorticoids group was less than the number in riboflavin group (P < 0.05).On the other hand,almost half of the patients in riboflavin group still presented high-level muscle enzymes and weak muscle strength after 1-month riboflavin treatment,meaning that 1-month treatment duration maybe insufficient and patients should keep on riboflavin supplement for a longer time.Conclusions:Our results provide credible evidences that the overall efficacy of riboflavin is superior to glucocorticoids,and a longer duration of riboflavin treatment is necessary for patients with late-onset MADD.

  10. Separation of flow

    CERN Document Server

    Chang, Paul K

    2014-01-01

    Interdisciplinary and Advanced Topics in Science and Engineering, Volume 3: Separation of Flow presents the problem of the separation of fluid flow. This book provides information covering the fields of basic physical processes, analyses, and experiments concerning flow separation.Organized into 12 chapters, this volume begins with an overview of the flow separation on the body surface as discusses in various classical examples. This text then examines the analytical and experimental results of the laminar boundary layer of steady, two-dimensional flows in the subsonic speed range. Other chapt

  11. Entrainment separator performance

    International Nuclear Information System (INIS)

    Clean and dust-loaded ACS entrainment separators mounted upstream of HEPA filters were exposed to a combination of fine water mist and steam at about 700C from one to four hours. In every trial, the ACS entrainment separator prevented measurable deterioration of performance in the following HEPA filter. Droplet size-efficiency evaluation of the ACS entrainment separators showed that, within the accuracy of the measurements, they meet all service requirements and are fully equal to the best separator units available for service on pressurized water reactors

  12. High resolution crystal structures of unliganded and liganded human liver ACBP reveal a new mode of binding for the acyl-CoA ligand

    DEFF Research Database (Denmark)

    Taskinen, Jukka P; van Aalten, Daan M; Knudsen, Jens;

    2007-01-01

    The acyl-CoA binding protein (ACBP) is essential for the fatty acid metabolism, membrane structure, membrane fusion, and ceramide synthesis. Here high resolution crystal structures of human cytosolic liver ACBP, unliganded and liganded with a physiological ligand, myristoyl-CoA are described...... are filled by other ligand fragments. This novel binding mode shows that the acyl moiety can flip out of its classical binding pocket and bind elsewhere, suggesting a mechanism for the acyl-CoA transfer between ACBP and the active site of a target enzyme. This mechanism is of possible relevance...

  13. Arabidopsis cytosolic acyl-CoA-binding proteins ACBP4, ACBP5 and ACBP6 have overlapping but distinct roles in seed development

    OpenAIRE

    Hsiao, An-Shan; Haslam, Richard P.; Michaelson, Louise V.; Liao, Pan; Chen, Qin-Fang; Sooriyaarachchi, Sanjeewani; Mowbray, Sherry L.; Napier, Johnathan A.; Tanner, Julian A.; Chye, Mee-Len

    2014-01-01

    Eukaryotic cytosolic ACBPs (acyl-CoA-binding proteins) bind acyl-CoA esters and maintain a cytosolic acyl-CoA pool, but the thermodynamics of their protein-lipid interactions and physiological relevance in plants are not well understood. Arabidopsis has three cytosolic ACBPs which have been identified as AtACBP4, AtACBP5 and AtACBP6, and microarray data indicated that all of them are expressed in seeds; AtACBP4 is expressed in early embryogenesis, whereas AtACBP5 is expressed later. ITC (isot...

  14. Selective ion flotation (foam separation)

    International Nuclear Information System (INIS)

    Batch and continuous experiments were carried out on the foam separation of the oxygen compounds of subgroup 4, 5, 6 and 7 transition metals with the cationic surfactant of (R) 4N+ type at various concentrations and pH of the aqueous solution. The experimental conditions were established basing on the ionic structure analysis for the aqueous solution of oxygen compounds of the metals studied, where as most of them occured as simple oxyanions. The metals studied can be divided into two main groups. The first group comprises V(5), Cr(6), Mo(6), W(6), Tc(7), and Re(7) occuring as simple oxyanions in the aqueous solution. The second group encompasses Ti(4), Zr(4), Hf(4), Nb(5), Ta(5), and Mn(7). Under experimantal conditions, metals classed among the second group were found to form colloidal systems or large polyoxyanions of somewhat sophisticated formulae and spatial structure built of MeO6 octahedra. It was experimentally shown that the intensity of anion flotation, equal to the batch flotation rate constant determined for individual ions under the same conditions, can be used as a measure of the affinity of anions for the cationic surfactant. The flotation selectivity orders, obtained in this way, are valid for adequate multicomponent solutions and similar to the flotation selectivity orders found during the continuous equilibrium foam separation. (author)

  15. Method for separating isotopes

    Science.gov (United States)

    Jepson, B.E.

    1975-10-21

    Isotopes are separated by contacting a feed solution containing the isotopes with a cyclic polyether wherein a complex of one isotope is formed with the cyclic polyether, the cyclic polyether complex is extracted from the feed solution, and the isotope is thereafter separated from the cyclic polyether.

  16. Nonterminal Separating Macro Grammars

    NARCIS (Netherlands)

    Hogendorp, Jan Anne; Asveld, P.R.J.; Nijholt, A.; Verbeek, Leo A.M.

    1987-01-01

    We extend the concept of nonterminal separating (or NTS) context-free grammar to nonterminal separating $m$-macro grammar where the mode of derivation $m$ is equal to "unrestricted". "outside-in' or "inside-out". Then we show some (partial) characterization results for these NTS $m$-macro grammars.

  17. Social Separation in Monkeys.

    Science.gov (United States)

    Mineka, Susan; Suomi, Stephen J.

    1978-01-01

    Reviews phenomena associated with social separation from attachment objects in nonhuman primates. Evaluates four theoretical treatments of separation in light of existing data: Bowlby's attachment-object-loss theory, Kaufman's conservation-withdrawal theory, Seligman's learned helplessness theory, and Solomon and Corbit's opponent-process theory.…

  18. Separators for flywheel rotors

    Science.gov (United States)

    Bender, Donald A.; Kuklo, Thomas C.

    1998-01-01

    A separator forms a connection between the rotors of a concentric rotor assembly. This separator allows for the relatively free expansion of outer rotors away from inner rotors while providing a connection between the rotors that is strong enough to prevent disassembly. The rotor assembly includes at least two rotors referred to as inner and outer flywheel rings or rotors. This combination of inner flywheel ring, separator, and outer flywheel ring may be nested to include an arbitrary number of concentric rings. The separator may be a segmented or continuous ring that abuts the ends of the inner rotor and the inner bore of the outer rotor. It is supported against centrifugal loads by the outer rotor and is affixed to the outer rotor. The separator is allowed to slide with respect to the inner rotor. It is made of a material that has a modulus of elasticity that is lower than that of the rotors.

  19. Group X

    Energy Technology Data Exchange (ETDEWEB)

    Fields, Susannah

    2007-08-16

    This project is currently under contract for research through the Department of Homeland Security until 2011. The group I was responsible for studying has to remain confidential so as not to affect the current project. All dates, reference links and authors, and other distinguishing characteristics of the original group have been removed from this report. All references to the name of this group or the individual splinter groups has been changed to 'Group X'. I have been collecting texts from a variety of sources intended for the use of recruiting and radicalizing members for Group X splinter groups for the purpose of researching the motivation and intent of leaders of those groups and their influence over the likelihood of group radicalization. This work included visiting many Group X websites to find information on splinter group leaders and finding their statements to new and old members. This proved difficult because the splinter groups of Group X are united in beliefs, but differ in public opinion. They are eager to tear each other down, prove their superiority, and yet remain anonymous. After a few weeks of intense searching, a list of eight recruiting texts and eight radicalizing texts from a variety of Group X leaders were compiled.

  20. Acyl coenzyme A synthetase long-chain 1 (ACSL1 gene polymorphism (rs6552828 and elite endurance athletic status: a replication study.

    Directory of Open Access Journals (Sweden)

    Thomas Yvert

    Full Text Available The aim of this study was to determine the association between the rs6552828 polymorphism in acyl coenzyme A synthetase (ACSL1 and elite endurance athletic status. We studied 82 Caucasian (Spanish World/Olympic-class endurance male athletes, and a group of sex and ethnically matched healthy young adults (controls, n=197. The analyses were replicated in a cohort of a different ethnic origin (Chinese of the Han ethnic group, composed of elite endurance athletes (runners [cases, n=241 (128 male] and healthy sedentary adults [controls, n=504 (267 male]. In the Spanish cohort, genotype (P=0.591 and minor allele (A frequencies were similar in cases and controls (P=0.978. In the Chinese cohort, genotype (P=0.973 and minor allele (G frequencies were comparable in female endurance athletes and sedentary controls (P=0.881, whereas in males the frequency of the G allele was higher in endurance athletes (0.40 compared with their controls (0.32, P=0.040. The odds ratio (95%CI for an elite endurance Chinese athlete to carry the G allele compared with ethnically matched controls was 1.381 (1.015-1.880 (P-value=0.04. Our findings suggest that the ACSL1 gene polymorphism rs6552828 is not associated with elite endurance athletic status in Caucasians, yet a marginal association seems to exist for the Chinese (Han male population.

  1. On the Unusual Homeoviscous Adaptation of the Membrane Fatty Acyl Components against the Thermal Stress in Rhi{Zeta}obium meliloti

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Seb Yung; Jung, Seun Ho [Konkuk University, Seoul (Korea, Republic of); Choi, Yong Hoon; Yang, Chul Hak [Seoul National University, Seoul (Korea, Republic of); Kim, Hyun Won [Yonsei University Wonju College of Medicine, Wonju (Korea, Republic of)

    1999-06-15

    In order to maintain the optimal fluidity in membrane, microorganism genetically regulates the ratio of the unsaturated fatty acids (Ufos) to saturated ones of its biological membrane in response to external perturbing condition such as the change of temperature. The remodelling of fatty acyl chain composition is the most frequently observed response to altered growth temperature. It is reflected in the elevated proportions of unsaturated fatty acid (UFAs) at low temperature. Because cis double bonds, normally positioned at the middle of fatty acyl chains, introduce a kink of approximately 30 .deg. into acyl chain, UFAs pack less compactly and exhibit lower melting points than their saturated homologues. Thus, enrichment of membranes with UFAs offsets, to a significant degree, the increase in membrane order caused by a drop in temperature. This is so called homeoviscous adaptation of the membrane fatty acyl chains against thermal stress. Membrane maintains the optimal viscosity using homeoviscous adaptation.

  2. Characterization of two members among the five ADP-forming acyl coenzyme A (Acyl-CoA) synthetases reveals the presence of a 2-(Imidazol-4-yl)acetyl-CoA synthetase in Thermococcus kodakarensis.

    Science.gov (United States)

    Awano, Tomotsugu; Wilming, Anja; Tomita, Hiroya; Yokooji, Yuusuke; Fukui, Toshiaki; Imanaka, Tadayuki; Atomi, Haruyuki

    2014-01-01

    The genome of Thermococcus kodakarensis, along with those of most Thermococcus and Pyrococcus species, harbors five paralogous genes encoding putative α subunits of nucleoside diphosphate (NDP)-forming acyl coenzyme A (acyl-CoA) synthetases. The substrate specificities of the protein products for three of these paralogs have been clarified through studies on the individual enzymes from Pyrococcus furiosus and T. kodakarensis. Here we have examined the biochemical properties of the remaining two acyl-CoA synthetase proteins from T. kodakarensis. The TK0944 and TK2127 genes encoding the two α subunits were each coexpressed with the β subunit-encoding TK0943 gene. In both cases, soluble proteins with an α2β2 structure were obtained and their activities toward various acids in the ADP-forming reaction were examined. The purified TK0944/TK0943 protein (ACS IIITk) accommodated a broad range of acids that corresponded to those generated in the oxidative metabolism of Ala, Val, Leu, Ile, Met, Phe, and Cys. In contrast, the TK2127/TK0943 protein exhibited relevant levels of activity only toward 2-(imidazol-4-yl)acetate, a metabolite of His degradation, and was thus designated 2-(imidazol-4-yl)acetyl-CoA synthetase (ICSTk), a novel enzyme. Kinetic analyses were performed on both proteins with their respective substrates. In T. kodakarensis, we found that the addition of histidine to the medium led to increases in intracellular ADP-forming 2-(imidazol-4-yl)acetyl-CoA synthetase activity, and 2-(imidazol-4-yl)acetate was detected in the culture medium, suggesting that ICSTk participates in histidine catabolism. The results presented here, together with those of previous studies, have clarified the substrate specificities of all five known NDP-forming acyl-CoA synthetase proteins in the Thermococcales. PMID:24163338

  3. Lie algebra contractions and separation of variables

    CERN Document Server

    Vinternits, P; Pogosyan, G S; Sissakian, A N

    2001-01-01

    The concept of analytical Lie group contractions is introduced to relate the separation of variables in space of constant nonzero curvature to separation in Euclidean or pseudo-Euclidean spaces. The contraction parameter is introduced explicitly into the basis of the Lie algebra, the Laplace-Beltrami operator, the complete set of commuting operators, the coordinates themselves and into the solutions. This enables to obtain asymptotic formulae connecting special functions related to the groups O(n) and O(n,1) to those related to Euclidean and pseudo-Euclidean groups

  4. Rotary drum separator system

    Science.gov (United States)

    Barone, Michael R. (Inventor); Murdoch, Karen (Inventor); Scull, Timothy D. (Inventor); Fort, James H. (Inventor)

    2009-01-01

    A rotary phase separator system generally includes a step-shaped rotary drum separator (RDS) and a motor assembly. The aspect ratio of the stepped drum minimizes power for both the accumulating and pumping functions. The accumulator section of the RDS has a relatively small diameter to minimize power losses within an axial length to define significant volume for accumulation. The pumping section of the RDS has a larger diameter to increase pumping head but has a shorter axial length to minimize power losses. The motor assembly drives the RDS at a low speed for separating and accumulating and a higher speed for pumping.

  5. On separable Pauli equations

    OpenAIRE

    Zhalij, Alexander

    2002-01-01

    We classify (1+3)-dimensional Pauli equations for a spin-1/2 particle interacting with the electro-magnetic field, that are solvable by the method of separation of variables. As a result, we obtain the eleven classes of vector-potentials of the electro-magnetic field A(t,x) providing separability of the corresponding Pauli equations. It is established, in particular, that the necessary condition for the Pauli equation to be separable into second-order matrix ordinary differential equations is...

  6. Characterization and cloning of a stearoyl/oleoyl specific fatty acyl-acyl carrier protein thioesterase from the seeds of Madhuca longifolia (latifolia).

    Science.gov (United States)

    Ghosh, Santosh K; Bhattacharjee, Ashish; Jha, Jyoti K; Mondal, Ashis K; Maiti, Mrinal K; Basu, Asitava; Ghosh, Dolly; Ghosh, Sudhamoy; Sen, Soumitra K

    2007-12-01

    Deposition of oleate, stearate and palmitate at the later stages of seed development in Mahua (Madhuca longifolia (latifolia)), a tropical non-conventional oil seed plant, has been found to be the characteristic feature of the regulatory mechanism that produces the saturated fatty acid rich Mahua seed fat (commonly known as Mowrah fat). Although, the content of palmitate has been observed to be higher than that of stearate at the initial stages of seed development, it goes down when the stearate and oleate contents consistently rise till maturity. The present study was undertaken in order to identify the kind of acyl-ACP thioesterase(s) that drives the characteristic composition of signature fatty acids (oleate 37%, palmitate 25%, stearate 23%, linoleate 12.5%) in its seed oil at maturity. The relative Fat activities in the crude protein extracts of the matured seeds towards three thioester substrates (oleoyl-, stearoyl- and palmitoyl-ACP) have been found to be present in the following respective ratio 100:31:8. Upon further purification of the crude extract, the search revealed the presence of two partially purified thioesterases: a long-chain oleoyl preferring house-keeping LC-Fat and a novel stearoyl-oleoyl preferring SO-Fat. The characteristic accumulation of oleate and linoleate in the M. latifolia seed fat is believed to be primarily due to the thioesterase activity of the LC-Fat or MlFatA. On the other hand, the SO-Fat showed almost equal substrate specificity towards stearoyl- and oleoyl-ACP, when its activity towards palmitoyl-ACP compared to stearoyl-ACP was only about 12%. An RT-PCR based technique for cloning of a DNA fragment from the mRNA pool of the developing seed followed by nucleotide sequencing resulted in the identification of a FatB type of thioesterase gene (MlFatB). This gene was found to exist as a single copy in the mother plant genome. Ectopic expression of this MlFatB gene product in E. coli strain fadD88 further proved that it induced a

  7. Characterization and cloning of a stearoyl/oleoyl specific fatty acyl-acyl carrier protein thioesterase from the seeds of Madhuca longifolia (latifolia).

    Science.gov (United States)

    Ghosh, Santosh K; Bhattacharjee, Ashish; Jha, Jyoti K; Mondal, Ashis K; Maiti, Mrinal K; Basu, Asitava; Ghosh, Dolly; Ghosh, Sudhamoy; Sen, Soumitra K

    2007-12-01

    Deposition of oleate, stearate and palmitate at the later stages of seed development in Mahua (Madhuca longifolia (latifolia)), a tropical non-conventional oil seed plant, has been found to be the characteristic feature of the regulatory mechanism that produces the saturated fatty acid rich Mahua seed fat (commonly known as Mowrah fat). Although, the content of palmitate has been observed to be higher than that of stearate at the initial stages of seed development, it goes down when the stearate and oleate contents consistently rise till maturity. The present study was undertaken in order to identify the kind of acyl-ACP thioesterase(s) that drives the characteristic composition of signature fatty acids (oleate 37%, palmitate 25%, stearate 23%, linoleate 12.5%) in its seed oil at maturity. The relative Fat activities in the crude protein extracts of the matured seeds towards three thioester substrates (oleoyl-, stearoyl- and palmitoyl-ACP) have been found to be present in the following respective ratio 100:31:8. Upon further purification of the crude extract, the search revealed the presence of two partially purified thioesterases: a long-chain oleoyl preferring house-keeping LC-Fat and a novel stearoyl-oleoyl preferring SO-Fat. The characteristic accumulation of oleate and linoleate in the M. latifolia seed fat is believed to be primarily due to the thioesterase activity of the LC-Fat or MlFatA. On the other hand, the SO-Fat showed almost equal substrate specificity towards stearoyl- and oleoyl-ACP, when its activity towards palmitoyl-ACP compared to stearoyl-ACP was only about 12%. An RT-PCR based technique for cloning of a DNA fragment from the mRNA pool of the developing seed followed by nucleotide sequencing resulted in the identification of a FatB type of thioesterase gene (MlFatB). This gene was found to exist as a single copy in the mother plant genome. Ectopic expression of this MlFatB gene product in E. coli strain fadD88 further proved that it induced a

  8. Hot Groups.

    Science.gov (United States)

    Vail, Kathleen

    1996-01-01

    Collaborators sparked by creative ideas and obsessed by a common task may not realize they're part of a "hot group"--a term coined by business professors Harold J. Leavitt and Jean Lipman-Blumen. Spawned by group decision making and employee empowerment, hot groups can flourish in education settings. They're typically small, short lived, and goal…

  9. Group morphology

    NARCIS (Netherlands)

    Roerdink, Jos B.T.M.

    2000-01-01

    In its original form, mathematical morphology is a theory of binary image transformations which are invariant under the group of Euclidean translations. This paper surveys and extends constructions of morphological operators which are invariant under a more general group TT, such as the motion group

  10. Separation of lanthanides through hydroxyapatite

    International Nuclear Information System (INIS)

    With the objective of obtaining from an independent way to each one of the lanthanides 151 Pm, 161 Tb, 166 Ho and 177 Lu free of carrier and with high specific activities starting from the indirect irradiation via, it intends in this work to determine the viability of separation of the couples Nd/Pm, Dy/Ho, Gd/Tb and Yb/Lu, by means of ion exchange column chromatography, using hydroxyapatite (HAp) and fluorite like absorbent material in complexing media. It is important to mention that have registered separation studies among lanthanides of the heavy group with those of the slight group, using the same mass and, in comparison with this work, quantities different from the father were used and of the son, also, that the separation studies were carried out among neighboring lanthanides. In this investigation, it was determined the effect that its have the complexing media: KSCN, sodium tartrate, sodium citrate, EDTA and aluminon, their pH and concentration, in the adsorption of the lanthanides in both minerals, in order to determine the chromatographic conditions for separation of the couples Nd/Pm, Dy/Ho, Gd/Tb and Yb/Lu. The work consists of five chapters, in the first one they are presented a theoretical introduction of the characteristics more important of the lanthanides, the hydroxyapatite and the fluorite; in the second, it is deepened in the ion exchange, as well as the two techniques (XRD and High Vacuum Electron Microscopy) to make the characterization of LnCI3 (Ln = Nd, Gd, Dy or Yb) synthesized. The third chapter, it describes the methodology continued in our experimental work; in the room, its are presented the obtained results of the static and dynamic method to determine the viability of separation of neighboring lanthanides; and finally, the five chapter shows the conclusions. In this study, it is concludes that the separation among neighboring lanthanides cannot be carried out in the minerals and used media; because practically these lanthanides

  11. Binding of the Cationic Peptide (KL)4K to Lipid Monolayers at the Air-Water Interface: Effect of Lipid Headgroup Charge, Acyl Chain Length, and Acyl Chain Saturation.

    Science.gov (United States)

    Hädicke, André; Blume, Alfred

    2016-04-28

    The binding of the cationic peptide (KL)4K to monolayers of different anionic lipids was determined by adsorption experiments. The chemical structure of the anionic phospholipids was changed in different ways. First, the hydrophobic region of phosphatidylglycerols was altered by elongation of the acyl chain length. Second, an unsaturated chain was introduced. Third, lipids with negatively charged headgroups of different chemical structure were compared. (KL)4K itself shows no surface activity and does not bind to monolayers of zwitterionic lipids. Analysis of (KL)4K binding to anionic lipid monolayers reveals a competition between two binding processes: (i) incorporation of the peptide into the acyl chain region (surface pressure increase) and (ii) electrostatic interaction screening the negative charges with reduction of charge repulsion (surface pressure decrease due to monolayer condensation). The lipid acyl chain length and the chemical structure of the headgroup have minor effects on the binding properties. However, a strong dependence on the phase state of the monolayer was observed. In the liquid-expanded (LE) phase, the fluid monolayer provides enough space, so that peptide insertion due to hydrophobic interactions dominates. For monolayers in the liquid-condensed (LC) phase, peptide binding followed by monolayer condensation is the main effect. PMID:27049846

  12. The first three years of screening for medium chain acyl-CoA dehydrogenase deficiency (MCADD by newborn screening ontario

    Directory of Open Access Journals (Sweden)

    Fisher Lawrence

    2010-11-01

    Full Text Available Abstract Background Medium chain acyl-CoA dehydrogenase deficiency (MCADD is a disorder of mitochondrial fatty acid oxidation and is one of the most common inborn errors of metabolism. Identification of MCADD via newborn screening permits the introduction of interventions that can significantly reduce associated morbidity and mortality. This study reports on the first three years of newborn screening for MCADD in Ontario, Canada. Methods Newborn Screening Ontario began screening for MCADD in April 2006, by quantification of acylcarnitines (primarily octanoylcarnitine, C8 in dried blood spots using tandem mass spectrometry. Babies with positive screening results were referred to physicians at one of five regional Newborn Screening Treatment Centres, who were responsible for diagnostic evaluation and follow-up care. Results From April 2006 through March 2009, approximately 439 000 infants were screened for MCADD in Ontario. Seventy-four infants screened positive, with a median C8 level of 0.68 uM (range 0.33-30.41 uM. Thirty-one of the screen positive infants have been confirmed to have MCADD, while 36 have been confirmed to be unaffected. Screening C8 levels were higher among infants with MCADD (median 8.93 uM compared to those with false positive results (median 0.47 uM. Molecular testing was available for 29 confirmed cases of MCADD, 15 of whom were homozygous for the common c.985A > G mutation. Infants homozygous for the common mutation tended to have higher C8 levels (median 12.13 uM relative to compound heterozygotes for c.985A > G and a second detectable mutation (median 2.01 uM. Eight confirmed mutation carriers were identified among infants in the false positive group. The positive predictive value of a screen positive for MCADD was 46%. The estimated birth prevalence of MCADD in Ontario is approximately 1 in 14 000. Conclusions The birth prevalence of MCADD and positive predictive value of the screening test were similar to those

  13. Arabidopsis cytosolic acyl-CoA-binding proteins ACBP4, ACBP5 and ACBP6 have overlapping but distinct roles in seed development

    Science.gov (United States)

    Hsiao, An-Shan; Haslam, Richard P.; Michaelson, Louise V.; Liao, Pan; Chen, Qin-Fang; Sooriyaarachchi, Sanjeewani; Mowbray, Sherry L.; Napier, Johnathan A.; Tanner, Julian A.; Chye, Mee-Len

    2014-01-01

    Eukaryotic cytosolic ACBPs (acyl-CoA-binding proteins) bind acyl-CoA esters and maintain a cytosolic acyl-CoA pool, but the thermodynamics of their protein–lipid interactions and physiological relevance in plants are not well understood. Arabidopsis has three cytosolic ACBPs which have been identified as AtACBP4, AtACBP5 and AtACBP6, and microarray data indicated that all of them are expressed in seeds; AtACBP4 is expressed in early embryogenesis, whereas AtACBP5 is expressed later. ITC (isothermal titration calorimetry) in combination with transgenic Arabidopsis lines were used to investigate the roles of these three ACBPs from Arabidopsis thaliana. The dissociation constants, stoichiometry and enthalpy change of AtACBP interactions with various acyl-CoA esters were determined using ITC. Strong binding of recombinant (r) AtACBP6 with long-chain acyl-CoA (C16- to C18-CoA) esters was observed with dissociation constants in the nanomolar range. However, the affinity of rAtACBP4 and rAtACBP5 to these acyl-CoA esters was much weaker (dissociation constants in the micromolar range), suggesting that they interact with acyl-CoA esters differently from rAtACBP6. When transgenic Arabidopsis expressing AtACBP6pro::GUS was generated, strong GUS (β-glucuronidase) expression in cotyledonary-staged embryos and seedlings prompted us to measure the acyl-CoA contents of the acbp6 mutant. This mutant accumulated higher levels of C18:1-CoA and C18:1- and C18:2-CoAs in cotyledonary-staged embryos and seedlings, respectively, in comparison with the wild type. The acbp4acbp5acbp6 mutant showed the lightest seed weight and highest sensitivity to abscisic acid during germination, suggesting their physiological functions in seeds. PMID:25423293

  14. A New Strategy for the Synthesis of 3-Acyl-coumarin Using Mesoporous Molecular Sieve MCM-41 as a Novel and Efficient Catalyst

    Institute of Scientific and Technical Information of China (English)

    HERAVI,Majid M; POORMOHAMMAD,Nargess; BEHESHTIGA,Yahia Sh; BAGHERNEJAD,Bita; MALAKOOTI,Reihaneh

    2009-01-01

    3-Acyl-coumarins were obtained in high yields from ortho-hydroxybenzaldehydes and ethyl acetoacetate or ethyl benzoylacetate in acetonitrile in the presence of a catalytic amount of mesoporous molecular sieve MCM-41. 3-Acyl-coumarins were obtained in high yields from ortho-hydroxybenzaldehydes and ethyl acetoacetate or ethyl benzoylacetate in acetonitrile in the presence of a catalytic amount of mesoporous molecular sieve MCM-41.

  15. Permutation groups

    CERN Document Server

    Passman, Donald S

    2012-01-01

    This volume by a prominent authority on permutation groups consists of lecture notes that provide a self-contained account of distinct classification theorems. A ready source of frequently quoted but usually inaccessible theorems, it is ideally suited for professional group theorists as well as students with a solid background in modern algebra.The three-part treatment begins with an introductory chapter and advances to an economical development of the tools of basic group theory, including group extensions, transfer theorems, and group representations and characters. The final chapter feature

  16. Giardia fatty acyl-CoA synthetases as potential drug targets

    Directory of Open Access Journals (Sweden)

    Fengguang eGuo

    2015-07-01

    Full Text Available Giardiasis caused by Giardia intestinalis (syn. G. lamblia, G. duodenalis is one of the leading causes of diarrheal parasitic diseases worldwide. Although limited drugs to treat giardiasis are available, there are concerns regarding toxicity in some patients and the emerging drug resistance. By data-mining genome sequences, we observed that G. intestinalis is incapable of synthesizing fatty acids de novo. However, this parasite has five long-chain fatty acyl-CoA synthetases (GiACS1 to GiACS5 to activate fatty acids scavenged from the host. ACS is an essential enzyme because fatty acids need to be activated to form acyl-CoA thioesters before they can enter subsequent metabolism. In the present study, we performed experiments to explore whether some GiACS enzymes could serve as drug targets in Giardia. Based on the high-throughput datasets and protein modeling analyses, we initially studied the GiACS1 and GiACS2, because genes encoding these two enzymes were found to be more consistently expressed in varied parasite life cycle stages and when interacting with host cells based on previously reported transcriptome data. These two proteins were cloned and expressed as recombinant proteins. Biochemical analysis revealed that both had apparent substrate preference towards palmitic acid (C16:0 and myristic acid (C14:0, and allosteric or Michaelis-Menten kinetics on palmitic acid or ATP. The ACS inhibitor triacsin C inhibited the activity of both enzymes (IC50 = 1.56 µM, Ki = 0.18 µM for GiACS1 and IC50 = 2.28 µM, Ki = 0.23 µM for GiACS2, respectively and the growth of G. intestinalis in vitro (IC50 = 0.8 µM. As expected from giardial evolutionary characteristics, both GiACSs displayed differences in overall folding structure as compared with their human counterparts. These observations support the notion that some of the GiACS enzymes may be explored as drug targets in this parasite.

  17. Laser-Beam Separator

    Science.gov (United States)

    Mcdermid, I. S.

    1984-01-01

    Train of prisms and optical stop separate fundamental beam of laser from second and higher order harmonics of beam produced in certain crystals and by stimulated Raman scattering in gases and liquids.

  18. Molten salt electrolyte separator

    Science.gov (United States)

    Kaun, Thomas D.

    1996-01-01

    A molten salt electrolyte/separator for battery and related electrochemical systems including a molten electrolyte composition and an electrically insulating solid salt dispersed therein, to provide improved performance at higher current densities and alternate designs through ease of fabrication.

  19. Separator for alkaline batteries

    Science.gov (United States)

    Hoyt, H. W.; Pfluger, H. L.

    1968-01-01

    Separator compositions have been tested as components of three-plate silver-zinc oxide cells in a standard cycling test. Six materials meet imposed requirements, giving cycling performance superior to cellophane.

  20. Galaxy Groups

    Science.gov (United States)

    Tully, R. Brent

    2015-02-01

    Galaxy groups can be characterized by the radius of decoupling from cosmic expansion, the radius of the caustic of second turnaround, and the velocity dispersion of galaxies within this latter radius. These parameters can be a challenge to measure, especially for small groups with few members. In this study, results are gathered pertaining to particularly well-studied groups over four decades in group mass. Scaling relations anticipated from theory are demonstrated and coefficients of the relationships are specified. There is an update of the relationship between light and mass for groups, confirming that groups with mass of a few times {{10}12}{{M}⊙ } are the most lit up while groups with more and less mass are darker. It is demonstrated that there is an interesting one-to-one correlation between the number of dwarf satellites in a group and the group mass. There is the suggestion that small variations in the slope of the luminosity function in groups are caused by the degree of depletion of intermediate luminosity systems rather than variations in the number per unit mass of dwarfs. Finally, returning to the characteristic radii of groups, the ratio of first to second turnaround depends on the dark matter and dark energy content of the universe and a crude estimate can be made from the current observations of {{Ω}matter}˜ 0.15 in a flat topology, with a 68% probability of being less than 0.44.