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Novel Family (novel + family)
Selected AbstractsChemInform Abstract: Ln2(OH)5NO3×xH2O (Ln: Y, Gd,Lu): A Novel Family of Anion Exchange Intercalation Hosts.CHEMINFORM, Issue 15 2008Laura J. McIntyre Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Amorphous Cerium,Titanium Solid Solution Phosphate as a Novel Family of Band Gap Tunable Sunscreen Materials.CHEMINFORM, Issue 36 2003Nobuhito Imanaka Abstract For Abstract see ChemInform Abstract in Full Text. [source] Novel family of triphenylamine-containing, hole-transporting, amorphous, aromatic polyamides with stable electrochromic propertiesJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 10 2005Tzy-Hsiang Su Abstract We report the preparation and characterization of a series of novel electrochromic, aromatic poly(amine amide)s with pendent triphenylamine units. The synthesis proceeded via direct phosphorylation polycondensation between a novel diamine, N,N -bis(4-aminophenyl)- N,,N,-diphenyl-1,4-phenylenediamine, and various aromatic dicarboxylic acids. All the poly(amine amide)s were amorphous and readily soluble in many common organic solvents and could be solution-cast into transparent, tough, and flexible films with good mechanical properties. They exhibited good thermal stability and 10% weight-loss temperatures above 540 °C. Their glass-transition temperatures were 263,290 °C. These polymers in N -methyl-2-pyrrolidinone solutions exhibited strong ultraviolet,visible absorption peaks at 307,358 nm and photoluminescence peaks around 532,590 nm in the green region. The hole-transporting and electrochromic properties were studied with electrochemical and spectroelectrochemical methods. Cyclic voltammograms of poly(amine amide) films prepared by the casting of polymer solutions onto an indium tin oxide coated glass substrate exhibited two reversible oxidation redox couples at 0.65 and 1.03 V versus Ag/AgCl in an acetonitrile solution. All the poly(amine amide)s showed excellent stability with respect to their electrochromic characteristics; the color of the films changed from pale yellow to green and then blue at 0.85 and 1.25 V, respectively. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2085,2098, 2005 [source] In this issue: Biotechnology Journal 12/2009BIOTECHNOLOGY JOURNAL, Issue 12 2009Article first published online: 14 DEC 200 Genome-scale in silico modeling Milne et al., Biotechnol. J. 2009, 4, 1653,1670 Driven by advancements in high-throughput biological technologies and the growing number of sequenced genomes, the construction of in silico models at the genome scale has provided powerful tools to investigate a vast array of biological systems and applications. Nathan Price and colleagues review comprehensively the use of such models in industrial and medical biotechnology, including biofuel generation, food production, and drug development. As such, genome-scale models can provide a basis for rational genome-scale engineering and synthetic biology. Genome-scale in silico models promise to extend their application and analysis scope to become a transformative tool in biotechnology. From metagenomics to metaproteomics Tuffin et al., Biotechnol. J. 2009, 4, 1671,1683 Metagenomics emerged in the late 1990s as a tool for accessing and studying the collective microbial genetic material in the environment and has been widely predicted to reach new dimensions of the protein sequence space. A decade on, researchers from South Africa see that while several novel enzyme activities and protein structures have been identified the greatest advancement has been made in the isolation of novel protein sequences, some of which have no close relatives, form deeply branched lineages and even represent novel families. However, there is much room for improvement in the methods employed that need to be addressed in order to access novel biocatalytic activities. Recombinant secondary metabolites Schäfer et al., Biotechnol. J. 2009, 4, 1684,1703 Plants produce a high diversity of natural products or secondary metabolites which have interesting biological properties and quite a number are of medicinal importance. Their functions range from the protection against herbivores and/or microbial pathogens to defend against abiotic stress, e.g. UV-B exposure. Because the production of valuable natural products, such as the anticancer drugs paclitaxel, vinblastine or camptothecin in plants is a costly process, biotechnological alternatives to produce these alkaloids more economically become more and more important. This review provides an overview of the state of art to produce alkaloids in recombinant microorganisms, such as bacteria or yeast. In a longterm perspective, it will probably be possible to generate gene cassettes for complete pathways, which could then be used for the production of valuable natural products in bioreactors or for metabolic engineering of crop plants. [source] Metagenomic gene discovery: How far have we moved into novel sequence space?BIOTECHNOLOGY JOURNAL, Issue 12 2009Marla Tuffin Abstract Metagenomics emerged in the late 1990s as a tool for accessing and studying the collective microbial genetic material in the environment. The advent of the technology generated great excitement, as it has provided new opportunities and technologies for studying the wealth of microbial genetic diversity in the environment. Metagenomics has been widely predicted to access new dimensions of protein sequence space. A decade on, we review how far we have actually moved into new sequence space (and other aspects of protein space) using metagenomic tools. While several novel enzyme activities and protein structures have been identified through metagenomic strategies, the greatest advancement has been made in the isolation of novel protein sequences, some of which have no close relatives, form deeply branched lineages and even represent novel families. This is particularly true for glycosyl hydrolases and lipase/esterases, despite the fact that these activities are frequently screened for in metagenomic studies. However, there is much room for improvement in the methods employed and they will need to be addressed so that access to novel biocatalytic activities can be widened. [source] Icosahedral and Ring-Shaped Allotropes of ArsenicCHEMPHYSCHEM, Issue 16 2007Antti J. Karttunen Dr. Abstract We predict the existence of two novel families of arsenic nanostructures: icosahedral cages and ring-shaped chains. Quantum chemical calculations on the cages, rings, and the experimentally known allotropes of arsenic suggest the nanostructures to be thermodynamically stable. The icosahedral cages are modifications of the gray allotrope of arsenic, while the ring-shaped chains are structurally related to the red allotrope of phosphorus. Comparisons between the analogous allotropes of arsenic and phosphorus show distinct differences. While phosphorus favors the ring-shaped chains over the icosahedral cages, large cages become favorable for arsenic. From the thermodynamical point of view, experimental preparation of the proposed families of arsenic nanostructures is expected to be viable. [source] Comparative genomics of the Mill family: a rapidly evolving MHC class,I gene familyEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 6 2004Yutaka Watanabe Abstract Mill (MHC class,I-like located near the leukocyte receptor complex) is a novel family of class,I genes identified in mice that is most closely related to the human MICA/B family. In the present study, we isolated Mill cDNA from rats and carried out a comparative genomic analysis. Rats have two Mill genes orthologous to mouse Mill1 and Mill2 near the leukocyte receptor complex, with expression patterns similar to those of their mouse counterparts. Interspecies sequence comparison indicates that Mill is one of the most rapidly evolving class,I gene families and that non-synonymous substitutions occur more frequently than synonymous substitutions in its ,,1 domain, implicating the involvement of Mill in immune defenses. Interestingly, the ,,2 domain of rat Mill2 contains a premature stop codon in many inbred strains, indicating that Mill2 is not essential for survival. A computer search of the database identified a horse Mill -like expressed sequence tag, indicating that Mill emerged before the radiation of mammals. Hence, the failure to find Mill in human indicates strongly that it was lost from the human lineage. Our present work provides convincing evidence that Mill is akin to the MICA/B family, yet constitutes a distinctgene family. [source] Cascade Annulation Reactions To Access the Structural Cores of Stereochemically Unusual Strychnos AlkaloidsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 10 2009Ricardo Delgado Abstract A new cascade annulation reaction has been developed to access the core structures of a novel family of strychnos alkaloids with a unique stereochemical arrangement. The new annulation cascade is facilitated by the development of a robust reaction sequence to access extremely sensitive N -acyliminium ions. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Acrylic Nanocomposite Resins for Use in Stereolithography and Structural Light Modulation Based Rapid Prototyping and Rapid Manufacturing Technologies,ADVANCED FUNCTIONAL MATERIALS, Issue 16 2008Matthias Gurr Abstract A novel family of optically transparent acrylic nanocomposites containing up to 30,wt,% silica nanoparticles with an average diameter of 20,nm was developed for application in structural light modulation (SLM) and stereolithography (SL) technologies. The uniform dispersion of nanoparticles affords a significantly improved toughness/stiffness-balance of the photopolymerized and postcured nanocomposites. It is possible to increase stiffness, as expressed by Young's modulus, from 1290 to 1700,MPa without encountering the embrittlement typical for many other conventional filled polymers. Fracture behaviour is examined by means of fracture mechanics investigation and SEM analyses of fracture surfaces. According to TEM analyses and measurement of optical transmittance remarkable uniform dispersion of silica nanoparticles was achieved. The silica nanoparticle concentrations up to 17,wt,% give only marginally higher viscosities and do not affect transmittance, while slightly increasing the exposure times needed in photopolymerization. Moreover, the silica nanoparticles afford materials with reduced shrinkage and improved properties. The green effective ankle splay out (EASO) measured on H-shaped diagnostic specimens, is significantly reduced for the nanocomposite materials from 1.38,mm for the unfilled material to 0.82,mm for nanocomposites containing 30,wt,% nanosilica. The building accuracy is increased significantly with increasing content of silica nanofillers. [source] Hexyl-Derivatized Poly(3,4-ethylenedioxyselenophene): Novel Highly Stable Organic Electrochromic Material with High Contrast Ratio, High Coloration Efficiency, and Low-Switching VoltageADVANCED MATERIALS, Issue 17 2009Mao Li A novel family of electrochromic materials has been discovered. The electropolymerized poly(hexyl-3,4-ethylenedioxyselenophene) film switches color between a highly absorbing pure blue and a nearly colorless bleached state, achieves both a high contrast ratio of 88,89% and a high CE of up to 773,cm2 C,1 while showing a fast switching time and remarkable stability with the contrast ratio remaining 48% after 10000 cycles. [source] Addressing volumetric locking and instabilities by selective integration in smoothed finite elementsINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING, Issue 1 2009Nguyen-Xuan Hung Abstract This paper promotes the development of a novel family of finite elements with smoothed strains, offering remarkable properties. In the smoothed finite element method (FEM), elements are divided into subcells. The strain at a point is defined as a weighted average of the standard strain field over a representative domain. This yields superconvergent stresses, both in regular and singular settings, as well as increased accuracy, with slightly lower computational cost than the standard FEM. The one-subcell version that does not exhibit volumetric locking yields more accurate stresses but less accurate displacements and is equivalent to a quasi-equilibrium FEM. It is also subject to instabilities. In the limit where the number of subcells goes to infinity, the standard FEM is recovered, which yields more accurate displacements and less accurate stresses. The specific contribution of this paper is to show that expressing the volumetric part of the strain field using a one-subcell formulation is sufficient to get rid of volumetric locking and increase the displacement accuracy compared with the standard FEM when the single subcell version is used to express both the volumetric and deviatoric parts of the strain. Selective integration also alleviates instabilities associated with the single subcell element, which are due to rank deficiency. Numerical examples on various compressible and incompressible linear elastic test cases show that high accuracy is retained compared with the standard FEM without increasing computational cost. Copyright © 2008 John Wiley & Sons, Ltd. [source] Cloning and Functional Analysis of a Family of Nuclear Matrix Transcription Factors (NP/NMP4) that Regulate Type I Collagen Expression in OsteoblastsJOURNAL OF BONE AND MINERAL RESEARCH, Issue 1 2001Pasutha Thunyakitpisal Abstract Collagen expression is coupled to cell structure in connective tissue. We propose that nuclear matrix architectural transcription factors link cell shape with collagen promoter geometry and activity. We previously indicated that nuclear matrix proteins (NP/NMP4) interact with the rat type I collagen ,1(I) polypeptide chain (COL1A1) promoter at two poly(dT) sequences (sites A and B) and bend the DNA. Here, our objective was to determine whether NP/NMP4- COL1A1 binding influences promoter activity and to clone NP/NMP4. Promoter-reporter constructs containing 3.5 kilobases (kb) of COL1A1 5, flanking sequence were fused to a reporter gene. Mutation of site A or site B increased promoter activity in rat UMR-106 osteoblast-like cells. Several full-length complementary DNAs (cDNAs) were isolated from an expression library using site B as a probe. These clones expressed proteins with molecular weights and COL1A1 binding activity similar to NP/NMP4. Antibodies to these proteins disrupted native NP/NMP4- COL1A1 binding activity. Overexpression of specific clones in UMR-106 cells repressed COL1A1 promoter activity. The isolated cDNAs encode isoforms of Cys2His2 zinc finger proteins that contain an AT-hook, a motif found in architectural transcription factors. Some of these isoforms recently have been identified as Cas-interacting zinc finger proteins (CIZ) that localize to fibroblast focal adhesions and enhance metalloproteinase gene expression. We observed NP/NMP4/CIZ expression in osteocytes, osteoblasts, and chondrocytes in rat bone. We conclude that NP/NMP4/CIZ is a novel family of nuclear matrix transcription factors that may be part of a general mechanical pathway that couples cell structure and function during extracellular matrix remodeling. [source] RNA binding motif (RBM) proteins: A novel family of apoptosis modulators?JOURNAL OF CELLULAR BIOCHEMISTRY, Issue 1 2005Leslie C. Sutherland Abstract RBM5 is a known modulator of apoptosis, an RNA binding protein, and a putative tumor suppressor. Originally identified as LUCA-15, and subsequently as H37, it was designated "RBM" (for RNA Binding Motif) due to the presence of two RRM (RNA Recognition Motif) domains within the protein coding sequence. Recently, a number of proteins have been attributed with this same RBM designation, based on the presence of one or more RRM consensus sequences. One such protein, RBM3, was also recently found to have apoptotic modulatory capabilities. The high sequence homology at the amino acid level between RBM5, RBM6, and particularly, RBM10 suggests that they, too, may play an important role in regulating apoptosis. It is the intent of this article to ammalgamate the data on the ten originally identified RBM proteins in order to question the existence of a novel family of RNA binding apoptosis regulators. © 2004 Wiley-Liss, Inc. [source] Highly stable electrochromic polyamides based on N,N -bis(4-aminophenyl)- N,,N,-bis(4- tert -butylphenyl)-1,4-phenylenediamineJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 9 2009Sheng-Huei Hsiao Abstract A new triphenylamine-containing aromatic diamine monomer, N,N -bis(4-aminophenyl)- N,,N,-bis(4- tert -butylphenyl)-1,4-phenylenediamine, was synthesized by an established synthetic procedure from readily available reagents. A novel family of electroactive polyamides with di- tert -butyl-substituted N,N,N,,N,-tetraphenyl-1,4-phenylenediamine units were prepared via the phosphorylation polyamidation reactions of the newly synthesized diamine monomer with various aromatic or aliphatic dicarboxylic acids. All the polymers were amorphous with good solubility in many organic solvents, such as N -methyl-2-pyrrolidinone (NMP) and N,N -dimethylacetamide, and could be solution-cast into tough and flexible polymer films. The polyamides derived from aromatic dicarboxylic acids had useful levels of thermal stability, with glass-transition temperatures of 269,296 °C, 10% weight-loss temperatures in excess of 544 °C, and char yields at 800 °C in nitrogen higher than 62%. The dilute solutions of these polyamides in NMP exhibited strong absorption bands centered at 316,342 nm and photoluminescence maxima around 362,465 nm in the violet-blue region. The polyamides derived from aliphatic dicarboxylic acids were optically transparent in the visible region and fluoresced with a higher quantum yield compared with those derived from aromatic dicarboxylic acids. The hole-transporting and electrochromic properties were examined by electrochemical and spectro-electrochemical methods. Cyclic voltammograms of the polyamide films cast onto an indium-tin oxide-coated glass substrate exhibited two reversible oxidation redox couples at 0.57,0.60 V and 0.95,0.98 V versus Ag/AgCl in acetonitrile solution. The polyamide films revealed excellent elcterochemical and electrochromic stability, with a color change from a colorless or pale yellowish neutral form to green and blue oxidized forms at applied potentials ranging from 0.0 to 1.2 V. These anodically coloring polymeric materials showed interesting electrochromic properties, such as high coloration efficiency (CE = 216 cm2/C for the green coloring) and high contrast ratio of optical transmittance change (,T%) up to 64% at 424 nm and 59% at 983 nm for the green coloration, and 90% at 778 nm for the blue coloration. The electroactivity of the polymer remains intact even after cycling 500 times between its neutral and fully oxidized states. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2330,2343, 2009 [source] Poly(ether tert -amine): A novel family of multiresponsive polymerJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 5 2009Yanrong Ren Abstract A novel multiresponsive poly(ether tert -amine) (PEA) was synthesized by nucleophilic addition/ring-opening reaction of commercial poly(ethylene oxide) (PEO), poly(propylene oxide) (PPO), and di-epoxy and di-amine monomer. The process of synthesis was very simple and green in ethanol as reactive media. These PEAs exhibit sharp response to temperature, pH, and ionic strength, with adjustable and sharp phase transitions in the range of 27,100 °C. The lower critical solution temperature (LCST) of PEA's aqueous solution presents a linear relationship to the PEO content (y = 35.7 + x), indicating well-tunable LCST. The concentration of PEA has no obvious effect on LCST. Therefore, PEA will be potential in applications of drug delivery, separation, and biotechnology. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 1292,1297, 2009 [source] Synthesis and in vitro degradation of poly(N -vinyl-2-pyrrolidone)-based graft copolymers for biomedical applicationsJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 21 2002Carl F. Brunius Abstract This work is devoted to the design of a novel family of hydrosoluble biomaterials: poly(N -vinyl-2-pyrrolidone) (PVP)-based graft copolymers. A synthesis route has been elaborated in which ,-functionalized PVP is prepared via chain-transfer radical polymerization, end-group modified, and subsequently grafted onto a polyhydroxylated backbone, typically dextran or poly(vinyl alcohol). The resulting graft copolymer biomaterials are designed for use in various biomedical applications, particularly as materials with a stronger potential for plasma expansion than already existing products have. The graft copolymers are potentially degradable because the PVP grafts are connected to the polyol backbone via a hydrolytically labile carbonate or ester linkage. The degradation of the graft copolymers was performed in vitro over a period of 6 weeks. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 3652,3661, 2002 [source] Fragile X syndrome, the Fragile X related proteins, and animal modelsMICROSCOPY RESEARCH AND TECHNIQUE, Issue 3 2002André T. Hoogeveen Abstract The Fragile X syndrome (FraX), which is characterized among other physical and neurologic impairments by mental retardation, is caused by the absence of the product of the FMR1 gene. The Fragile X Mental Retardation Protein (FMRP) is a member of a novel family of RNA-binding proteins. The latter includes two other proteins highly homologous with FMRP: the fragile X related proteins 1 and 2 (FXRP1 and FXRP2). Characterization of FXRPs, including their interaction with FMRP, will provide critical information about the mechanisms of action of FMRP and the role of this group of proteins in FMRP-deficient conditions such as FraX. Genetic manipulations of FMRP and the FXRPs should also provide valuable tools for investigating pathophysiology and gene therapies in FraX. The present review summarizes the strategies used for identifying the FXRPs, their chromosomal localization, molecular structure, and tissue distribution. It also reviews interactions between different members of this family of RNA-binding proteins. Animal models, both knockout and transgenic, of FMRP and the FXRPs are discussed. Phenotypic features of the FMR1 knockout mouse, the FMR1 transgenic rescue mouse, and other novel strategies for manipulating and delivering FMRP and FXRPs to the brain and other tissues are described. Microsc. Res. Tech. 57:148,155, 2002. © 2002 Wiley-Liss, Inc. [source] A novel family of regulated helicases/nucleases from Gram-positive bacteria: insights into the initiation of DNA recombinationMOLECULAR MICROBIOLOGY, Issue 4 2002Frédéric Chédin First page of article [source] The Nep1-like proteins,a growing family of microbial elicitors of plant necrosisMOLECULAR PLANT PATHOLOGY, Issue 4 2004CLARE L. PEMBERTON SUMMARY A novel family of microbial elicitors of plant necrosis has been identified. Designated Nep1-like proteins (NLPs), after the first family member isolated, they range from 24 to 26 kDa and are found in a variety of taxonomically unrelated micro-organisms. These include several fungi and oomycetes, as well as Gram-positive and Gram-negative bacteria. Some NLPs induce a hypersensitive-like response in plants, although the basis for initiation of this response remains unclear. Similarly, the cellular role of such highly conserved proteins is undetermined. It is not clear whether the NLPs are dedicated elicitors of plant defences or whether this induction occurs as a result of another activity. [source] Micellar solutions of amphipathic copolymers based on carboxymethyl cellulosePOLYMER INTERNATIONAL, Issue 6 2003Ya Cao Abstract A novel family of amphipathic copolymers based on carboxymethyl cellulose (CM-cellulose) has been synthesized through ultrasonic irradiation. Their micellar conformation in aqueous solution was studied by dynamic laser scattering, environmental scanning electron microscopy and gel permeation chromatography. The results show that conformation of copolymer molecules is totally different from that of CM-cellulose because of the introduction of the surface active macromonomers. Due to the influence of hydrophobic character and molecular weight, different amphipathic copolymers have different micellar conformations, such as cylindrical, spheroidal or ellipsoidal micelles. In the range of concentration tested, the normalized first-order autocorrelation function g(1)(,) of a copolymer of CM-cellulose and poly(ethylene oxide) dodecyl ether acrylate does not fit a single-exponential decay, indicating a polydisperse system and the existence of species of different shapes and size. At different concentrations, the hydrodynamic radii of micelles (R) almost distribute into two regions of smaller and larger size. With increasing copolymer concentration, the region of smaller R remains in the range 30,100,nm and is considered to represent monomolecular micelles, while the larger R region increases gradually with concentration, which means that polymolecular micelles increase in size. © 2003 Society of Chemical Industry [source] Discovering robust protein biomarkers for disease from relative expression reversals in 2-D DIGE data.PROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 8 2007Troy J. Anderson Abstract This study assesses the ability of a novel family of machine learning algorithms to identify changes in relative protein expression levels, measured using 2-D DIGE data, which support accurate class prediction. The analysis was done using a training set of 36 total cellular lysates comprised of six normal and three cancer biological replicates (the remaining are technical replicates) and a validation set of four normal and two cancer samples. Protein samples were separated by 2-D DIGE and expression was quantified using DeCyder-2D Differential Analysis Software. The relative expression reversal (RER) classifier correctly classified 9/9 training biological samples (p<0.022) as estimated using a modified version of leave one out cross validation and 6/6 validation samples. The classification rule involved comparison of expression levels for a single pair of protein spots, tropomyosin isoforms and ,-enolase, both of which have prior association as potential biomarkers in cancer. The data was also analyzed using algorithms similar to those found in the extended data analysis package of DeCyder software. We propose that by accounting for sources of within- and between-gel variation, RER classifiers applied to 2-D DIGE data provide a useful approach for identifying biomarkers that discriminate among protein samples of interest. [source] Identification of a novel family of 70 kDa microtubule-associated proteins in Arabidopsis cellsTHE PLANT JOURNAL, Issue 4 2005Andrey V. Korolev Summary Most plant microtubule-associated proteins (MAPs) have homologues across the phylogenetic spectrum. To find potential plant-specific MAPs that will have evaded bioinformatic searches we devised a low stringency method for isolating proteins from an Arabidopsis cell suspension on endogenous taxol-microtubules. By tryptic peptide mass fingerprinting we identified 55 proteins that were enriched on taxol-microtubules. Amongst a range of known MAPs, such as kinesins, MAP65 isoforms and MOR1, we detected ,unknown' 70 kDa proteins that belong to a family of five closely related Arabidopsis proteins having no known homologues amongst non-plant organisms. To verify that AtMAP70-1 associates with microtubules in vivo, it was expressed as a GFP fusion. This confirmed that the protein decorates all four microtubule arrays in both transiently infected Arabidopsis and stably transformed tobacco BY-2 suspension cells. Microtubule-directed drugs perturbed the localization of AtMAP70-1 but cytochalasin D did not. AtMAP70-1 contains four predicted coiled-coil domains and truncation studies identified a central domain that targets the fusion protein to microtubules in vivo. This study therefore introduces a novel family of plant-specific proteins that interact with microtubules. [source] Large, larger, largest , a family of cluster-based tantalum copper aluminides with giant unit cells.ACTA CRYSTALLOGRAPHICA SECTION B, Issue 3 2009This is the first of two parts, where we report the structure determination of a novel family of cluster-based intermetallic phases of unprecedented complexity: cF444-Al63.6Ta36.4 (AT-19), a = 19.1663,(1),Å, V = 7040,Å3, cF(5928,,,x)-Al56.6Cu3.9Ta39.5, x = 20 (ACT-45), a = 45.376,(1),Å, V = 93,428,Å3 and cF(23,256,,,x)-Al55.4Cu5.4Ta39.1, x = 122 (ACT-71), a = 71.490,(4),Å, V = 365,372,Å3. The space group is in all three cases. These cluster-based structures are closely related to the class of Frank,Kasper phases. It is remarkable that all three structures show the same average structure that resembles the cubic Laves phase. [source] Large, larger, largest , a family of cluster-based tantalum copper aluminides with giant unit cells.ACTA CRYSTALLOGRAPHICA SECTION B, Issue 3 2009This is the second of two papers, where we discuss the cluster structures of a novel family of cluster-based intermetallic phases of unprecedented complexity: cF444-Al63.6Ta36.4 (AT-19), a = 19.1663,(1),Å, V = 7040,Å3, cF(5928,,,x)-Al56.6Cu3.9Ta39.5, x = 20 (ACT-45), a = 45.376,(1),Å, V = 93,428,Å3 and cF(23,,256,,,x)-Al55.4Cu5.4Ta39.1, x = 122 (ACT-71), a = 71.490,(4),Å, V = 365,372,Å3. The space group is in all three cases. The structures can be described as packings of clusters such as fullerenes, dodecahedra, pentagonal bifrusta and Friauf polyhedra. A characteristic feature of the two larger structures are nets of hexagonal bipyramidal Ta clusters (h.b.p.). The extremely short distance of 2.536,2.562,Å between their apical Ta atoms indicates unusually strong bonding. The large h.b.p. nets are sandwiched between slabs of Friauf polyhedra resembling the structure of the , phase. [source] Two enantiomerically pure cyclic arenesulfonamide hydrochloride saltsACTA CRYSTALLOGRAPHICA SECTION C, Issue 2 2009Lionel Kiefer The crystal structures of N -[(1R)-1-(1-naphthyl)ethyl]-3,4-dihydro-2H -1,2-benzothiazin-4-aminium 1,1-dioxide chloride, C20H21N2O2S+·Cl,, (I), a six-membered cyclic sulfonamide, and (1R)- N -[(5,5-dioxo-6,7-dihydrodibenzo[d,f][1,2]thiazepin-7-yl)methyl]-1-(1-naphthyl)ethanaminium chloride, C26H25N2O2S+·Cl,, (II), a seven-membered cyclic sulfonamide, both representative of a novel family of agonists of the extracellular calcium sensing receptor (CaSR) of possible clinical importance, are reported. The known chirality of the naphthylethylamine precursor has enabled assignment of the absolute configuration of both compounds, which is crucial for the receptor recognition. The crystal structures, though different, reveal for these agonists a notable absence of intramolecular ,,, stacking between their respective aromatic groups. This suggests a common structural feature that allows CaSR agonists to be distinguished from antagonists, since in the latter, such interactions have been shown to be important. The connectivities between molecules in the crystal structures are also different, but both involve hydrogen bonding mediated by chloride ions as a common dominant feature. [source] Characterization of a novel pectate lyase, Pel10A, from Pseudomonas cellulosaACTA CRYSTALLOGRAPHICA SECTION D, Issue 8 2001Simon J. Charnock Biological recycling of plant material is essential for biosphere maintenance. This perpetual task involves a complex array of enzymes, including extracellular polysaccharide hydrolases and lyases. Whilst much is known about the structure and function of the hydrolases, relatively little is known about the structures and mechanisms of the corresponding lyases. To this end, crystals of the catalytic module of a novel family 10 pectate lyase, Pel10A from Pseudomonas cellulosa, were obtained using polyethylene glycol 2000 monomethylether as a precipitant. They belong to space group P21, with unit-cell parameters a = 47.7, b = 106.1, c = 55.4,Å, , = 92.0°, and have two molecules in the asymmetric unit. The crystals diffract beyond 1.5,Å using synchrotron radiation. [source] GAPs in Slit-Robo signalingBIOESSAYS, Issue 5 2002Aurnab Ghose Neuronal migration requires the integration of a number of diverse environmental cues and subsequent translation to specific responses such as directed cytoskeletal remodeling. Accurate knowledge of the signal transduction pathways linking activation of surface receptors to actin dynamics is necessary in order to understand the regulation of such processes. Activation of the Roundabout (Robo) receptor mediates a repulsive response in certain pioneering axons and migratory neurons. Recently, Wong et al.1 have described a signaling link between Robo activation and specific GTPase activity that appears to regulate neuronal migration. A novel family of GTPase regulators, responsive to Slit-Robo engagement, has been identified and convincingly shown to alter the migration of neuronal cells. This study not only delineates a specific signaling route from guidance receptors to directed neuronal movement, but also offers clues towards potential regulatory mechanisms that ensure specificity of the Slit-Robo response. BioEssays 24:401,404, 2002. © 2002 Wiley Periodicals, Inc. [source] Protease-activated receptors and prostaglandins in inflammatory lung diseaseBRITISH JOURNAL OF PHARMACOLOGY, Issue 4 2009Terence Peters Protease-activated receptors (PARs) are a novel family of G protein-coupled receptors. Signalling through PARs typically involves the cleavage of an extracellular region of the receptor by endogenous or exogenous proteases, which reveals a tethered ligand sequence capable of auto-activating the receptor. A considerable body of evidence has emerged over the past 20 years supporting a prominent role for PARs in a variety of human physiological and pathophysiological processes, and thus substantial attention has been directed towards developing drug-like molecules that activate or block PARs via non-proteolytic pathways. PARs are widely expressed within the respiratory tract, and their activation appears to exert significant modulatory influences on the level of bronchomotor tone, as well as on the inflammatory processes associated with a range of respiratory tract disorders. Nevertheless, there is debate as to whether the principal response to PAR activation is an augmentation or attenuation of airways inflammation. In this context, an important action of PAR activators may be to promote the generation and release of prostanoids, such as prostglandin E2, which have well-established anti-inflammatory effects in the lung. In this review, we primarily focus on the relationship between PARs, prostaglandins and inflammatory processes in the lung, and highlight their potential role in selected respiratory tract disorders, including pulmonary fibrosis, asthma and chronic obstructive pulmonary disease. This article is part of a themed issue on Mediators and Receptors in the Resolution of Inflammation. To view this issue visit http://www3.interscience.wiley.com/journal/121548564/issueyear?year=2009 [source] Biological activities of Bv8 analoguesBRITISH JOURNAL OF PHARMACOLOGY, Issue 5 2005Lucia Negri The small protein Bv8, secreted by the skin of the frog Bombina variegata, belongs to a novel family of secreted proteins whose orthologues have been identified in snakes (MIT) and in mammals (prokineticins (PKs)). A characteristic feature of this protein family is the same N-terminal sequence, AVITGA, and the presence of 10 cysteines with identical spacing in the C-terminal domain. Two closely related G protein-coupled receptors that mediate signal transduction of Bv8/PKs have been cloned (PK-R1 and PK-R2). In mammals, the Bv8/PK protein family is involved in a number of biological activities such as ingestive behaviours, circadian rhythms, angiogenesis and pain sensitization. In an attempt to identify the structural determinants required for the pronociceptive activity of Bv8, we prepared Bv8 derivatives lacking one (des-Ala- Bv8) or two (des-Ala-Val -Bv8) residues from the N-terminus. des-Ala- Bv8 displayed a receptor affinity five times lower than that of Bv8, it was five times less potent in inducing [Ca2+]i transients and in causing p42/p44 MAPK phosphorylation in CHO-cells expressing PK-R1 and PK-R2. Moreover, dA-Bv8 was about 20 times less potent than Bv8 in inducing hyperalgesia in rats. The deletion of the first two amino acids of Bv8 abolished any biological activity both ,in vitro' and ,in vivo'; however, des-AlaVal -Bv8 is able to antagonize the Bv8-induced hyperalgesia, binding the PK-Rs on peripheral and central projections of the primary sensitive neurons. British Journal of Pharmacology (2005) 146, 625,632. doi:10.1038/sj.bjp.0706376 [source] Tunable DNA Cleavage by Intercalating PeptidoconjugatesCHEMBIOCHEM, Issue 5 2006Kerry P. Mahon Jr. Abstract The properties of a novel family of peptide-based DNA-cleavage agents are described. Examination of the DNA-cleavage activities of a systematic series of peptide,intercalator conjugates revealed trends that show a strong dependence on peptide sequence. Conjugates differing by a single residue displayed reactivities that varied over a wide range. The cleavage activity was modulated by the electrostatic or steric qualities of individual amino acids. Isomeric conjugates that differed in the position of the tether also exhibited different reactivities. The mechanism of DNA cleavage for these compounds was also probed and was determined to involve hydrogen-atom abstraction from the DNA backbone. Previous studies of these compounds indicated that amino acid peroxides were the active agents in the cleavage reaction; in this report, the chemistry underlying the reaction is characterized. The results reported provide insight into how peptide sequences can be manipulated to produce biomimetic compounds. [source] | |||||||||||||||||||||||||||||||