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Sample records for ancillary pilin subunit

  1. Lactobacillus rhamnosus GG SpaC pilin subunit binds to the carbohydrate moieties of intestinal glycoconjugates.

    Science.gov (United States)

    Nishiyama, Keita; Ueno, Shintaro; Sugiyama, Makoto; Yamamoto, Yuji; Mukai, Takao

    2016-06-01

    Lactobacillus rhamnosus GG (LGG) is a well-established probiotic strain. The beneficial properties of this strain are partially dependent on its prolonged residence in the gastrointestinal tract, and are likely influenced by its adhesion to the intestinal mucosa. The pilin SpaC subunit, located within the Spa pili structure, is the most well studied LGG adhesion factor. However, the binding epitopes of SpaC remain largely unknown. The aim of this study was to evaluate the binding properties of SpaC to the carbohydrate moieties of intestinal glycoconjugates using a recombinant SpaC protein. In a competitive enzyme-linked immunosorbent assay, SpaC binding was markedly reduced by addition of purified mucin and the mucin oligosaccharide fraction. Histochemical staining revealed that the binding of SpaC was drastically reduced by periodic acid treatment. Moreover, in the surface plasmon resonance-based Biacore assay, SpaC bound strongly to the carbohydrate moieties containing β-galactoside at the non-reducing terminus of glycolipids. We here provide the first demonstration that SpaC binds to the oligosaccharide chains of mucins, and that the carbohydrate moieties containing β-galactoside at the non-reducing termini of glycoconjugates play a crucial role in this binding. Our results demonstrate the importance of carbohydrates of SpaC for mucus interactions. PMID:26434750

  2. Crystallization and X-ray Crystallographic Analysis of the Adhesive SpaC Pilin Subunit in the SpaCBA Pilus of Gut-adapted Lactobacillus rhamnosus GG.

    Science.gov (United States)

    Kant, Abhiruchi; von Ossowski, Ingemar; Palva, Airi; Krishnan, Vengadesan

    2016-01-01

    Gram-positive Lactobacillus rhamnosus GG, a gut-adapted commensalic (and probiotic) strain, is known to express sortase-assembled pili on its cell surface. These SpaCBA-called pili consist of three different types of building blocks; the SpaA backbone-pilin subunit and the SpaB and SpaC ancillary pilins. SpaC is a relatively large (~90kDa) multi-domain fimbrial adhesin, and while it is located primarily at the SpaCBA pilus tip, occasionally, it can also be detected throughout the length of pilus backbone. Functionally, SpaC mainly accounts for SpaCBA pilus-mediated interactions with intestinal mucus, collagen, and human gut epithelial cells. Moreover, SpaC adhesiveness is also perceived to have a causal relationship with SpaCBA pilus-induced host-cell immune responses. In order to improve the mechanistic understanding of SpaC and its adhesive properties by structural investigation, we purified and successfully crystallized a recombinant construct of the near full-length SpaC protein (residues 36-856) in the presence of magnesium ions. X-ray diffraction data were collected to 2.6 Å resolution. The SpaC crystal belongs to the space group P21212 with unit cell parameters a = 116.5, b = 128.3, c = 136.5 Å and contains two molecules in the asymmetric unit. Presence of conserved metal ion-dependent adhesion site containing von Willebrand factor type A domain suggests its likely role in the function of SpaC. PMID:26732247

  3. Phylogeny, clinical associations, and diagnostic utility of the pilin subunit gene (sfpA) of sorbitol-fermenting, enterohemorrhagic Escherichia coli O157:H-

    NARCIS (Netherlands)

    Friedrich, Alexander W; Nierhoff, Katja V; Bielaszewska, Martina; Mellmann, Alexander; Karch, Helge

    2004-01-01

    The plasmid-borne sfpA gene encodes the pilin subunit in sorbitol-fermenting (SF) enterohemorrhagic Escherichia coli (EHEC) O157:H-. We investigated the distribution of sfpA among 600 E. coli isolates comprising the complete E. coli standard reference (ECOR) and diarrheagenic E. coli (DEC) strain co

  4. Pilin Processing Follows a Different Temporal Route than That of Archaellins in Methanococcus maripaludis

    Directory of Open Access Journals (Sweden)

    Divya B. Nair

    2015-01-01

    Full Text Available Methanococcus maripaludis has two different surface appendages: type IV-like pili and archaella. Both structures are believed to be assembled using a bacterial type IV pilus mechanism. Each structure is composed of multiple subunits, either pilins or archaellins. Both pilins and archaellins are made initially as preproteins with type IV pilin-like signal peptides, which must be removed by a prepilin peptidase-like enzyme. This enzyme is FlaK for archaellins and EppA for pilins. In addition, both pilins and archaellins are modified with N-linked glycans. The archaellins possess an N-linked tetrasaccharide while the pilins have a pentasaccharide which consists of the archaellin tetrasaccharide but with an additional sugar, an unidentified hexose, attached to the linking sugar. In this report, we show that archaellins can be processed by FlaK in the absence of N-glycosylation and N-glycosylation can occur on archaellins that still retain their signal peptides. In contrast, pilins are not glycosylated unless they have been acted on by EppA to have the signal peptide removed. However, EppA can still remove signal peptides from non-glycosylated pilins. These findings indicate that there is a difference in the order of the posttranslational modifications of pilins and archaellins even though both are type IV pilin-like proteins.

  5. Structural Characterization of Novel Pseudomonas aeruginosa Type IV Pilins

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Y.; Jackson, S; Aidoo, F; Junop, M; Burrows, L

    2010-01-01

    Pseudomonas aeruginosa type IV pili, composed of PilA subunits, are used for attachment and twitching motility on surfaces. P. aeruginosa strains express one of five phylogenetically distinct PilA proteins, four of which are associated with accessory proteins that are involved either in pilin posttranslational modification or in modulation of pilus retraction dynamics. Full understanding of pilin diversity is crucial for the development of a broadly protective pilus-based vaccine. Here, we report the 1.6-{angstrom} X-ray crystal structure of an N-terminally truncated form of the novel PilA from strain Pa110594 (group V), which represents the first non-group II pilin structure solved. Although it maintains the typical T4a pilin fold, with a long N-terminal {alpha}-helix and four-stranded antiparallel {beta}-sheet connected to the C-terminus by a disulfide-bonded loop, the presence of an extra helix in the {alpha}{beta}-loop and a disulfide-bonded loop with helical character gives the structure T4b pilin characteristics. Despite the presence of T4b features, the structure of PilA from strain Pa110594 is most similar to the Neisseria gonorrhoeae pilin and is also predicted to assemble into a fiber similar to the GC pilus, based on our comparative pilus modeling. Interactions between surface-exposed areas of the pilin are suggested to contribute to pilus fiber stability. The non-synonymous sequence changes between group III and V pilins are clustered in the same surface-exposed areas, possibly having an effect on accessory protein interactions. However, based on our high-confidence model of group III PilA{sub PA14}, compensatory changes allow for maintenance of a similar shape.

  6. Crystallization and preliminary X-ray diffraction analysis of PsaA, the adhesive pilin subunit that forms the pH 6 antigen on the surface of Yersinia pestis

    International Nuclear Information System (INIS)

    The pH 6 antigen Psa displayed on the surface of Yersinia pestis, the bacterium that causes plague in humans, consists of polymers of a single protein subunit termed PsaA. Donor-strand complemented PsaA was purified and crystallized. Yersinia pestis has been responsible for a number of high-mortality epidemics throughout human history. Like all other bacterial infections, the pathogenesis of Y. pestis begins with the attachment of bacteria to the surface of host cells. At least five surface proteins from Y. pestis have been shown to interact with host cells. Psa, the pH 6 antigen, is one of them and is deployed on the surface of bacteria as thin flexible fibrils that are the result of the polymerization of a single PsaA pilin subunit. Here, the crystallization of recombinant donor-strand complemented PsaA by the hanging-drop vapor-diffusion method is reported. X-ray diffraction data sets were collected to 1.9 Å resolution from a native crystal and to 1.5 Å resolution from a bromide-derivatized crystal. These crystals displayed the symmetry of the orthorhombic space group P2221, with unit-cell parameters a = 26.3, b = 54.6, c = 102.1 Å. Initial phases were derived from single isomorphous replacement with anomalous scattering experiments, resulting in an electron-density map that showed a single molecule in the crystallographic asymmetric unit. Sequence assignment was aided by residues binding to bromide ions of the heavy-atom derivative

  7. The Pilin N-terminal Domain Maintains Neisseria gonorrhoeae Transformation Competence during Pilus Phase Variation.

    Science.gov (United States)

    Obergfell, Kyle P; Seifert, H Steven

    2016-05-01

    The obligate human pathogen Neisseria gonorrhoeae is the sole aetiologic agent of the sexually transmitted infection, gonorrhea. Required for gonococcal infection, Type IV pili (Tfp) mediate many functions including adherence, twitching motility, defense against neutrophil killing, and natural transformation. Critical for immune escape, the gonococcal Tfp undergoes antigenic variation, a recombination event at the pilE locus that varies the surface exposed residues of the major pilus subunit PilE (pilin) in the pilus fiber. This programmed recombination system has the potential to produce thousands of pilin variants and can produce strains with unproductive pilin molecules that are completely unable to form Tfp. Saturating mutagenesis of the 3' third of the pilE gene identified 68 unique single nucleotide mutations that each resulted in an underpiliated colony morphology. Notably, all isolates, including those with undetectable levels of pilin protein and no observable surface-exposed pili, retained an intermediate level of transformation competence not exhibited in ΔpilE strains. Site-directed, nonsense mutations revealed that only the first 38 amino acids of the mature pilin N-terminus (the N-terminal domain or Ntd) are required for transformation competence, and microscopy, ELISAs and pilus purification demonstrate that extended Tfp are not required for competence. Transformation in strains producing only the pilin Ntd has the same genetic determinants as wild-type transformation. The Ntd corresponds to the alternative product of S-pilin cleavage, a specific proteolysis unique to pathogenic Neisseria. Mutation of the S-pilin cleavage site demonstrated that S-pilin cleavage mediated release of the Ntd is required for competence when a strain produces unproductive pilin molecules that cannot assemble into a Tfp through mutation or antigenic variation. We conclude that S-pilin cleavage evolved as a mechanism to maintain competence in nonpiliated antigenic variants

  8. The Pilin N-terminal Domain Maintains Neisseria gonorrhoeae Transformation Competence during Pilus Phase Variation

    Science.gov (United States)

    2016-01-01

    The obligate human pathogen Neisseria gonorrhoeae is the sole aetiologic agent of the sexually transmitted infection, gonorrhea. Required for gonococcal infection, Type IV pili (Tfp) mediate many functions including adherence, twitching motility, defense against neutrophil killing, and natural transformation. Critical for immune escape, the gonococcal Tfp undergoes antigenic variation, a recombination event at the pilE locus that varies the surface exposed residues of the major pilus subunit PilE (pilin) in the pilus fiber. This programmed recombination system has the potential to produce thousands of pilin variants and can produce strains with unproductive pilin molecules that are completely unable to form Tfp. Saturating mutagenesis of the 3’ third of the pilE gene identified 68 unique single nucleotide mutations that each resulted in an underpiliated colony morphology. Notably, all isolates, including those with undetectable levels of pilin protein and no observable surface-exposed pili, retained an intermediate level of transformation competence not exhibited in ΔpilE strains. Site-directed, nonsense mutations revealed that only the first 38 amino acids of the mature pilin N-terminus (the N-terminal domain or Ntd) are required for transformation competence, and microscopy, ELISAs and pilus purification demonstrate that extended Tfp are not required for competence. Transformation in strains producing only the pilin Ntd has the same genetic determinants as wild-type transformation. The Ntd corresponds to the alternative product of S-pilin cleavage, a specific proteolysis unique to pathogenic Neisseria. Mutation of the S-pilin cleavage site demonstrated that S-pilin cleavage mediated release of the Ntd is required for competence when a strain produces unproductive pilin molecules that cannot assemble into a Tfp through mutation or antigenic variation. We conclude that S-pilin cleavage evolved as a mechanism to maintain competence in nonpiliated antigenic

  9. The Pilin N-terminal Domain Maintains Neisseria gonorrhoeae Transformation Competence during Pilus Phase Variation.

    Directory of Open Access Journals (Sweden)

    Kyle P Obergfell

    2016-05-01

    Full Text Available The obligate human pathogen Neisseria gonorrhoeae is the sole aetiologic agent of the sexually transmitted infection, gonorrhea. Required for gonococcal infection, Type IV pili (Tfp mediate many functions including adherence, twitching motility, defense against neutrophil killing, and natural transformation. Critical for immune escape, the gonococcal Tfp undergoes antigenic variation, a recombination event at the pilE locus that varies the surface exposed residues of the major pilus subunit PilE (pilin in the pilus fiber. This programmed recombination system has the potential to produce thousands of pilin variants and can produce strains with unproductive pilin molecules that are completely unable to form Tfp. Saturating mutagenesis of the 3' third of the pilE gene identified 68 unique single nucleotide mutations that each resulted in an underpiliated colony morphology. Notably, all isolates, including those with undetectable levels of pilin protein and no observable surface-exposed pili, retained an intermediate level of transformation competence not exhibited in ΔpilE strains. Site-directed, nonsense mutations revealed that only the first 38 amino acids of the mature pilin N-terminus (the N-terminal domain or Ntd are required for transformation competence, and microscopy, ELISAs and pilus purification demonstrate that extended Tfp are not required for competence. Transformation in strains producing only the pilin Ntd has the same genetic determinants as wild-type transformation. The Ntd corresponds to the alternative product of S-pilin cleavage, a specific proteolysis unique to pathogenic Neisseria. Mutation of the S-pilin cleavage site demonstrated that S-pilin cleavage mediated release of the Ntd is required for competence when a strain produces unproductive pilin molecules that cannot assemble into a Tfp through mutation or antigenic variation. We conclude that S-pilin cleavage evolved as a mechanism to maintain competence in nonpiliated

  10. The Type IV Pilin of Burkholderia mallei Is Highly Immunogenic but Fails To Protect against Lethal Aerosol Challenge in a Murine Model▿

    OpenAIRE

    Fernandes, Paula J.; Guo, Qin; Waag, David M.; Donnenberg, Michael S.

    2007-01-01

    Burkholderia mallei is the cause of glanders and a proven biological weapon. We identified and purified the type IV pilin protein of this organism to study its potential as a subunit vaccine. We found that purified pilin was highly immunogenic. Furthermore, mice infected via sublethal aerosol challenge developed significant increases in titers of antibody against the pilin, suggesting that it is expressed in vivo. Nevertheless, we found no evidence that high-titer antipilin antisera provided ...

  11. Antigenic variation of pilin regulates adhesion of Neisseria meningitidis to human epithelial cells.

    Science.gov (United States)

    Nassif, X; Lowy, J; Stenberg, P; O'Gaora, P; Ganji, A; So, M

    1993-05-01

    Pili have been shown to play an essential role in the adhesion of Neisseria meningitidis to epithelial cells. However, among piliated strains, both inter- and intrastrain variability exist with respect to their degree of adhesion to epithelial cells in vitro (Virji et al., 1992). This suggests that factors other than the presence of pili per se are involved in this process. The N. meningitidis pilin subunit undergoes extensive antigenic variation. Piliated low- and high-adhesive derivatives of the same N. meningitidis strain were selected and the nucleotide sequence of the pilin gene expressed in each was determined. The highly adhesive derivatives had the same pilin sequence. The alleles encoding the pilin subunit of the low-adhesive derivatives were completely different from the one found in the high-adhesive isolates. Using polyclonal antibodies raised against one hyperadhesive variant, it was confirmed that the low-adhesive piliated derivatives expressed pilin variants antigenically different from the highly adhesive strains. The role of antigenic variation in the adhesive process of N. meningitidis was confirmed by performing allelic exchanges of the pilE locus between low- and high-adhesive isolates. Antigenic variation has been considered a means by which virulent bacteria evade the host immune system. This work provides genetic proof that a bacterial pathogen, N. meningitidis, can use antigenic variation to modulate their degree of virulence. PMID:8332064

  12. The structure of the PapD-PapGII pilin complex reveals an open and flexible P5 pocket

    OpenAIRE

    Ford, Bradley; Verger, Denis; Dodson, Karen; Volkan, Ender; Kostakioti, Maria; Elam, Jennifer; Pinkner, Jerome; Waksman, Gabriel; Hultgren, Scott

    2012-01-01

    P pili are hairlike polymeric structures that mediate binding of uropathogenic Escherichia coli to the surface of the kidney via the PapG adhesin at their tips. PapG is composed of two domains: a lectin domain at the tip of the pilus followed by a pilin domain that comprises the initial polymerizing subunit of the 1,000-plus-subunit heteropolymeric pilus fiber. Prior to assembly, periplasmic pilin domains bind to a chaperone, PapD. PapD mediates donor strand complementation, in which a beta s...

  13. The F4 fimbrial chaperone FaeE is stable as a monomer that does not require self-capping of its pilin-interactive surfaces.

    Science.gov (United States)

    Van Molle, Inge; Moonens, Kristof; Buts, Lieven; Garcia-Pino, Abel; Panjikar, Santosh; Wyns, Lode; De Greve, Henri; Bouckaert, Julie

    2009-05-01

    Many Gram-negative bacteria use the chaperone-usher pathway to express adhesive surface structures, such as fimbriae, in order to mediate attachment to host cells. Periplasmic chaperones are required to shuttle fimbrial subunits or pilins through the periplasmic space in an assembly-competent form. The chaperones cap the hydrophobic surface of the pilins through a donor-strand complementation mechanism. FaeE is the periplasmic chaperone required for the assembly of the F4 fimbriae of enterotoxigenic Escherichia coli. The FaeE crystal structure shows a dimer formed by interaction between the pilin-binding interfaces of the two monomers. Dimerization and tetramerization have been observed previously in crystal structures of fimbrial chaperones and have been suggested to serve as a self-capping mechanism that protects the pilin-interactive surfaces in solution in the absence of the pilins. However, thermodynamic and biochemical data show that FaeE occurs as a stable monomer in solution. Other lines of evidence indicate that self-capping of the pilin-interactive interfaces is not a mechanism that is conservedly applied by all periplasmic chaperones, but is rather a case-specific solution to cap aggregation-prone surfaces. PMID:19390146

  14. Pilins in gram-positive bacteria: A structural perspective.

    Science.gov (United States)

    Krishnan, Vengadesan

    2015-07-01

    Pilins or fimbrilins are a class of proteins found in bacterial surface pilus, a hair-like surface appendage. Both the Gram-negative and -positive bacteria produce pilins to assemble pili on their cell-surface for different purposes including adherence, twitching motility, conjugation, immunomodulation, biofilm formation, and electron transfer. Immunogenic properties of the pilins make them attractive vaccine candidates. The polymerized pilins play a key role in the initiation of host adhesion, which is a critical step for bacterial colonization and infection. Because of their key role in adhesion and exposure on the cell surface, targeting the pilins-mediated adhesion (anti-adhesion therapy) is also seen as a promising alternative approach for preventing and treating bacterial infections, one that may overcome their ever-increasing repertoires of resistance mechanisms. Individual pilins interact with each other non-covalently to assemble the pilus fiber with the help of associated proteins like chaperones and Usher in Gram-negative bacteria. In contrast, the pilins in Gram-positive bacteria often connect with each other covalently, with the help of sortases. Certain unique structural features present on the pilins distinguish them from one another across different bacterial strains, and these dictate their cellular targets and functions. While the structure of pilins has been extensively studied in Gram-negative pathogenic bacteria, the pilins in Gram-positive pathogenic bacteria have been in only during the last decade. Recently, the discovery of pilins in non-pathogenic bacteria, such as Lactobacillus rhamnosus GG, has received great attention, though traditionally the attention was on pathogenic bacteria. This review summarizes and discusses the current structural knowledge of pilins in Gram-positive bacteria with emphasis on those pilins which are sortase substrates. PMID:26178080

  15. Structure of the Type IVa Major Pilin from the Electrically Conductive Bacterial Nanowires of Geobacter sulfurreducens

    Energy Technology Data Exchange (ETDEWEB)

    Reardon, Patrick N.; Mueller, Karl T.

    2013-10-11

    Several species of bacteria are capable of reducing insoluble metal oxides as well as other extracellular electron acceptors. These bacteria play a critical role in the cycling of minerals in subsurface environments, sediments, and groundwater. In some species of bacteria, such as Geobacter sulfurreducens, the transport of electrons is facilitated by filamentous fibers that are referred to as bacterial nanowires. These nanowires belong to the type IVa family of pilin proteins and are mainly comprised of one subunit protein, PilA. Here, we report the high resolution solution nuclear magnetic resonance (NMR) structure of the PilA protein from G. sulfurreducens determined in detergent micelles. The protein is over 85% α-helical and exhibits similar architecture to the N-terminal regions of other non-conductive type IVa pilins. The detergent micelle interacts with the first 21 amino acids of the protein, indicating that this region likely associates with the bacterial inner membrane prior to fiber formation. A model of the G. sulfurreducens pilus fiber is proposed based on docking of this structure into the fiber model of the type IVa pilin from Neisseria gonorrhoeae. This model provides insight into the organization of aromatic amino acids that are important for electrical conduction.

  16. Expression, purification, crystallization and preliminary crystallographic analysis of SpaA, a major pilin from Corynebacterium diphtheriae

    International Nuclear Information System (INIS)

    SpaA, one of the major pilins of C. diphtheriae, has been expressed, purified and crystallized and X-ray diffraction data have been collected to 1.6 Å resolution. Bacterial pili are cell-surface organelles that are critically involved in adhesion to host cells, leading to the colonization of host tissues and the establishment of infections. Whereas the pili of Gram-negative bacteria have been extensively studied, those of Gram-positive bacteria came to light only recently after the discovery and characterization of Corynebacterium diphtheriae pili. These newly discovered pili are formed by the covalent polymerization of pilin subunits catalyzed by sortase enzymes, making them fundamentally different from the noncovalent pilin assemblies of Gram-negative bacteria. Here, the expression, crystallization and preliminary crystallographic analysis of SpaA, which forms the shaft of one of the three types of pili expressed by C. diphtheriae, are reported. SpaA53–486 crystals diffracted to 1.6 Å resolution and belonged to space group P212121, with unit-cell parameters a = 34.9, b = 64.1, c = 198.7 Å, α = β = γ = 90°

  17. Escherichia coli DegP Protease Cleaves between Paired Hydrophobic Residues in a Natural Substrate: the PapA Pilin

    OpenAIRE

    Jones, C. Hal; Dexter, Paul; Evans, Amy K.; Liu, Christopher; Hultgren, Scott J.; Hruby, Dennis E.

    2002-01-01

    The DegP protein, a multifunctional chaperone and protease, is essential for clearance of denatured or aggregated proteins from the inner-membrane and periplasmic space in Escherichia coli. To date, four natural targets for DegP have been described: colicin A lysis protein, pilin subunits and MalS from E. coli, and high-molecular-weight adherence proteins from Haemophilus influenzae. In vitro, DegP has shown weak protease activity with casein and several other nonnative substrates. We report ...

  18. Ancillary investigations in uveitis

    OpenAIRE

    Vishali Gupta; Amod Gupta

    2013-01-01

    Ancillary investigations are the backbone of uveitis work-up both for anterior and posterior segment diseases. They help in making the diagnosis, ruling out certain differential diagnosis and monitoring inflammation during the follow-up. This review aims to be an overview describing the role of commonly used investigations for uveitis.

  19. Ancillary revenue pricing

    OpenAIRE

    Wittmer, Andreas; Oberlin, Nicole

    2014-01-01

    The airline industry has evolved from a system of long-established state owned carriers operating in a regular market to a dynamic, deregulated industry. This development - especially the emerging competition of Low Cost Carriers - had a major influence on the price setting behavior of airlines. Profitability of airlines is limited and pricing systems are reconsidered. In order to stay competitive traditional full service carriers consider the implementation of ancillary revenue systems (simi...

  20. Isopeptide bonds of the major pilin protein BcpA influence pilus structure and bundle formation on the surface of Bacillus cereus

    Energy Technology Data Exchange (ETDEWEB)

    Hendrickx, Antoni P.A.; Poor, Catherine B.; Jureller, Justin E.; Budzik, Jonathan M.; He, Chuan; Schneewind, Olaf (UC)

    2012-09-05

    Bacillus cereus strains elaborate pili on their surface using a mechanism of sortase-mediated cross-linking of major and minor pilus components. Here we used a combination of electron microscopy and atomic force microscopy to visualize these structures. Pili occur as single, double or higher order assemblies of filaments formed from monomers of the major pilin, BcpA, capped by the minor pilin, BcpB. Previous studies demonstrated that within assembled pili, four domains of BcpA -- CNA{sub 1}, CNA{sub 2}, XNA and CNA{sub 3} -- each acquire intramolecular lysine-asparagine isopeptide bonds formed via catalytic glutamic acid or aspartic acid residues. Here we showed that mutants unable to form the intramolecular isopeptide bonds in the CNA2 or CNA3 domains retain the ability to form pilus bundles. A mutant lacking the CNA{sub 1} isopeptide bond assembled deformed pilin subunits that failed to associate as bundles. X-ray crystallography revealed that the BcpA variant Asp{sup 312}Ala, lacking an aspartyl catalyst, did not generate the isopeptide bond within the jelly-roll structure of XNA. The Asp{sup 312}Ala mutant was also unable to form bundles and promoted the assembly of deformed pili. Thus, structural integrity of the CNA{sub 1} and XNA domains are determinants for the association of pili into higher order bundle structures and determine native pilus structure.

  1. Processing and maturation of the pilin of the type IV secretion system encoded within the gonococcal genetic island.

    Science.gov (United States)

    Jain, Samta; Kahnt, Jörg; van der Does, Chris

    2011-12-23

    The type IV secretion system (T4SS) encoded within the gonococcal genetic island (GGI) of Neisseria gonorrhoeae has homology to the T4SS encoded on the F plasmid. The GGI encodes the putative pilin protein TraA and a serine protease TrbI, which is homologous to the TraF protein of the RP4 plasmid involved in circularization of pilin subunits of P-type pili. TraA was processed to a 68-amino acid long circular peptide by leader peptidase and TrbI. Processing occurred after co-translational membrane insertion and was independent of other proteins. Circularization occurred after removal of three C-terminal amino acids. Mutational analysis of TraA revealed limited flexibility at the cleavage and joining sites. Mutagenesis of TrbI showed that the conserved Lys-93 and Asp-155 are essential, whereas mutagenesis of Ser-52, the putative catalytic serine did not influence circularization. Further mutagenesis of other serine residues did not identify a catalytic serine, indicating that TrbI either contains redundant catalytic serine residues or does not function via a serine-lysine dyad mechanism. In vitro studies revealed that circularization occurs via a covalent intermediate between the C terminus of TraA and TrbI. The intermediate is processed to the circular form after cleavage of the N-terminal signal sequence. This is the first demonstration of a covalent intermediate in the circularization mechanism of conjugative pili. PMID:22006923

  2. A slow-forming isopeptide bond in the structure of the major pilin SpaD from Corynebacterium diphtheriae has implications for pilus assembly

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Hae Joo; Paterson, Neil G. [University of Auckland, Private Bag 92019, Auckland 1142 (New Zealand); Kim, Chae Un [Cornell University, Ithaca, NY 14853 (United States); Middleditch, Martin [University of Auckland, Private Bag 92019, Auckland 1142 (New Zealand); Chang, Chungyu; Ton-That, Hung [University of Texas–Houston Medical School, Houston, TX 77030 (United States); Baker, Edward N., E-mail: ted.baker@auckland.ac.nz [University of Auckland, Private Bag 92019, Auckland 1142 (New Zealand)

    2014-05-01

    Two crystal structures of the major pilin SpaD from C. diphtheriae have been determined at 1.87 and 2.5 Å resolution. The N-terminal domain is found to contain an isopeptide bond that forms slowly over time in the recombinant protein. Given its structural context, this provides insight into the relationship between internal isopeptide-bond formation and pilus assembly. The Gram-positive organism Corynebacterium diphtheriae, the cause of diphtheria in humans, expresses pili on its surface which it uses for adhesion and colonization of its host. These pili are covalent protein polymers composed of three types of pilin subunit that are assembled by specific sortase enzymes. A structural analysis of the major pilin SpaD, which forms the polymeric backbone of one of the three types of pilus expressed by C. diphtheriae, is reported. Mass-spectral and crystallographic analysis shows that SpaD contains three internal Lys–Asn isopeptide bonds. One of these, shown by mass spectrometry to be located in the N-terminal D1 domain of the protein, only forms slowly, implying an energy barrier to bond formation. Two crystal structures, of the full-length three-domain protein at 2.5 Å resolution and of a two-domain (D2-D3) construct at 1.87 Å resolution, show that each of the three Ig-like domains contains a single Lys–Asn isopeptide-bond cross-link, assumed to give mechanical stability as in other such pili. Additional stabilizing features include a disulfide bond in the D3 domain and a calcium-binding loop in D2. The N-terminal D1 domain is more flexible than the others and, by analogy with other major pilins of this type, the slow formation of its isopeptide bond can be attributed to its location adjacent to the lysine used in sortase-mediated polymerization during pilus assembly.

  3. A slow-forming isopeptide bond in the structure of the major pilin SpaD from Corynebacterium diphtheriae has implications for pilus assembly

    International Nuclear Information System (INIS)

    Two crystal structures of the major pilin SpaD from C. diphtheriae have been determined at 1.87 and 2.5 Å resolution. The N-terminal domain is found to contain an isopeptide bond that forms slowly over time in the recombinant protein. Given its structural context, this provides insight into the relationship between internal isopeptide-bond formation and pilus assembly. The Gram-positive organism Corynebacterium diphtheriae, the cause of diphtheria in humans, expresses pili on its surface which it uses for adhesion and colonization of its host. These pili are covalent protein polymers composed of three types of pilin subunit that are assembled by specific sortase enzymes. A structural analysis of the major pilin SpaD, which forms the polymeric backbone of one of the three types of pilus expressed by C. diphtheriae, is reported. Mass-spectral and crystallographic analysis shows that SpaD contains three internal Lys–Asn isopeptide bonds. One of these, shown by mass spectrometry to be located in the N-terminal D1 domain of the protein, only forms slowly, implying an energy barrier to bond formation. Two crystal structures, of the full-length three-domain protein at 2.5 Å resolution and of a two-domain (D2-D3) construct at 1.87 Å resolution, show that each of the three Ig-like domains contains a single Lys–Asn isopeptide-bond cross-link, assumed to give mechanical stability as in other such pili. Additional stabilizing features include a disulfide bond in the D3 domain and a calcium-binding loop in D2. The N-terminal D1 domain is more flexible than the others and, by analogy with other major pilins of this type, the slow formation of its isopeptide bond can be attributed to its location adjacent to the lysine used in sortase-mediated polymerization during pilus assembly

  4. Ancillary experiments: Opportunities and challenges

    OpenAIRE

    Baldwin, Kate; Bhavnani, Rikhil R.

    2013-01-01

    Ancillary experiments' are a new technique whereby researchers use a completed experiment conducted by others to recover causal estimates of a randomized intervention on new outcomes. The method requires pairing new outcome data with randomized treatments the researchers themselves did not oversee. Since ancillary experiments rely on interventions that have already been undertaken, oftentimes by governments, they can provide a low-cost method with which to identify the effects of large-scale ...

  5. Ancillary Benefits of Climate Policy

    OpenAIRE

    Markandya, Anil; Rübbelke, Dirk T. G.

    2003-01-01

    The benefits of climate policy normally consist exclusively of the reduced impacts of climate change, i.e., the policy’s primary aim. Our analysis of benefits of climate policy suggests, however, that researchers and policymakers should also take account of ancillary benefits, e.g., in the shape of improved air quality induced by climate protection measures. A consideration of both, primary and ancillary benefits, has a positive influence on global climate protection efforts, e.g., because th...

  6. Ancillary Services from Wind Farms

    DEFF Research Database (Denmark)

    Meeting the EU objectives of sustainable energy supply in the near future involves a dramatic increase of the electricity demand covered by variable renewable sources, among which wind power holds an important role. This important role comes together with ever increasing requirements of wind powe...... plants ability of delivering ancillary services to the power system. The presentation attempts at giving an overview of the present (and future) research on the ability of large (offshore) wind farms to provide power system services....

  7. Ancillary service provision from distributed generation

    International Nuclear Information System (INIS)

    This report summarises the findings of a study undertaken to investigate the potential for establishing ancillary service markets at the distribution level in the UK. Existing arrangements for ancillary service markets globally, the design of these markets, regulatory and legislative changes that may be required, different forms of distributed generation (DG), and prospects of increasing the connection to the distributed network are examined along with commercial frameworks and technical procedures, infrastructure requirements, and the effects on different market participants. The scope for new ancillary services at the distribution level, ancillary services from DG, the prospects for DG, commercial and technical aspects, and impact assessments are reviewed

  8. Navigation and Ancillary Information Facility's SPICE

    Data.gov (United States)

    National Aeronautics and Space Administration — The Navigation and Ancillary Information Facility (NAIF), acting under the directions of NASA's Planetary Science Division, has built an information system named...

  9. Ancillary service provision from distributed generation

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    This report summarises the findings of a study undertaken to investigate the potential for establishing ancillary service markets at the distribution level in the UK. Existing arrangements for ancillary service markets globally, the design of these markets, regulatory and legislative changes that may be required, different forms of distributed generation (DG), and prospects of increasing the connection to the distributed network are examined along with commercial frameworks and technical procedures, infrastructure requirements, and the effects on different market participants. The scope for new ancillary services at the distribution level, ancillary services from DG, the prospects for DG, commercial and technical aspects, and impact assessments are reviewed.

  10. Immunization with a Pseudomonas aeruginosa 1244 Pilin Provides O-Antigen-Specific Protection▿

    OpenAIRE

    Horzempa, Joseph; Held, Thomas K.; Cross, Alan S.; Furst, Dana; Qutyan, Mohammed; Neely, Alice N.; Castric, Peter

    2008-01-01

    The O antigen is both a major structural outer membrane component and the dominant epitope of most gram-negative bacteria. Pseudomonas aeruginosa 1244 produces a type IV pilus and covalently links an O-antigen repeating unit to each pilin monomer. Here we show that immunization of mice with pure pilin from strain 1244 by use of either the mouse respiratory model or the thermal injury model resulted in protection from challenge with a pilus-null O-antigen-producing 1244 mutant. These results p...

  11. Structural basis of typhod: Salmonella typhi type IVb pilin (PilS) and cystic fibrosis transmembrane conductance regulator interaction

    Energy Technology Data Exchange (ETDEWEB)

    Balakrishna, A.; Saxena, A; Mok, H; Swaminathan, K

    2009-01-01

    The type IVb pilus of the enteropathogenic bacteria Salmonella typhi is a major adhesion factor during the entry of this pathogen into gastrointestinal epithelial cells. Its target of adhesion is a stretch of 10 residues from the first extracellular domain of cystic fibrosis transmembrane conductance regulator (CFTR). The crystal structure of the N-terminal 25 amino acid deleted S. typhi native PilS protein (PilS), which makes the pilus, was determined at 1.9 A resolution by the multiwavelength anomalous dispersion method. Also, the structure of the complex of PilS and a target CFTR peptide, determined at 1.8 A, confirms that residues 113-117 (NKEER) of CFTR are involved in binding with the pilin protein and gives us insight on the amino acids that are essential for binding. Furthermore, we have also explored the role of a conserved disulfide bridge in pilus formation. The subunit structure and assembly architecture are crucial for understanding pilus functions and designing suitable therapeutics against typhoid.

  12. Structural basis of typhoid: Salmonella typhi type IVb pilin (PiLS) and cystic fibrosis transmembrane conductance regulator interaction

    Energy Technology Data Exchange (ETDEWEB)

    Balakrishna, A.M.; Saxena, A.; Mok, H. Y.-K.; Swaminathan, K.

    2009-11-01

    The type IVb pilus of the enteropathogenic bacteria Salmonella typhi is a major adhesion factor during the entry of this pathogen into gastrointestinal epithelial cells. Its target of adhesion is a stretch of 10 residues from the first extracellular domain of cystic fibrosis transmembrane conductance regulator (CFTR). The crystal structure of the N-terminal 25 amino acid deleted S. typhi native PilS protein ({Delta}PilS), which makes the pilus, was determined at 1.9 {angstrom} resolution by the multiwavelength anomalous dispersion method. Also, the structure of the complex of {Delta}PilS and a target CFTR peptide, determined at 1.8 {angstrom}, confirms that residues 113-117 (NKEER) of CFTR are involved in binding with the pilin protein and gives us insight on the amino acids that are essential for binding. Furthermore, we have also explored the role of a conserved disulfide bridge in pilus formation. The subunit structure and assembly architecture are crucial for understanding pilus functions and designing suitable therapeutics against typhoid.

  13. Structural Basis of Typhoid: Salmonella typhi Type IVb pilin (PilS) and Cystic Fibrosis Transmembrane Conductance Regulatory Interaction

    Energy Technology Data Exchange (ETDEWEB)

    Balakrishna, A.; Saxena, A; Mok, H; Swaminathan, K

    2009-01-01

    The type IVb pilus of the enteropathogenic bacteria Salmonella typhi is a major adhesion factor during the entry of this pathogen into gastrointestinal epithelial cells. Its target of adhesion is a stretch of 10 residues from the first extracellular domain of cystic fibrosis transmembrane conductance regulator (CFTR). The crystal structure of the N-terminal 25 amino acid deleted S. typhi native PilS protein (PilS), which makes the pilus, was determined at 1.9 A resolution by the multiwavelength anomalous dispersion method. Also, the structure of the complex of PilS and a target CFTR peptide, determined at 1.8 A, confirms that residues 113-117 (NKEER) of CFTR are involved in binding with the pilin protein and gives us insight on the amino acids that are essential for binding. Furthermore, we have also explored the role of a conserved disulfide bridge in pilus formation. The subunit structure and assembly architecture are crucial for understanding pilus functions and designing suitable therapeutics against typhoid.

  14. Purification, crystallization and halide phasing of a Streptococcus agalactiae backbone pilin GBS80 fragment

    OpenAIRE

    Vengadesan, Krishnan; Ma, Xin; Dwivedi, Prabhat; Ton-That, Hung; Narayana, Sthanam V. L

    2010-01-01

    The C-terminal fragment of Streptococcus agalactiae (group B streptococcus) major (backbone) pilin GBS80 was purified and crystallized in two different space groups. Single-wavelength anomalous dispersion (SAD) data collected to 2.0 Å resolution on a iodide (NaI) derivative crystal using the home source were used to obtain initial phases.

  15. Exogam with its ancillary detectors

    International Nuclear Information System (INIS)

    The goal of the meeting was to discuss the status of experiments using Exogam and its ancillary detectors. Presentations include details of experiments already run and those in preparation. This document gathers most of the slides presented at the meeting. The results of 7 experiments are described. There are 9 contributions as it follows: 1) presentation of the Vamos spectrometer p.1-15, 2) the Clara (detector) and Prisma (spectrometer) setup: status and perspectives p.16-33, 3) experiment E344aS: shape coexistence near the N=Z line and collective properties of Kr isotopes investigated by low-energy Coulomb excitation p.34-56, 4) experiment E389: study of effective charges at Sm100 via the nuclear lifetime measurements in Pd96 and Cd98 p.57-68, 5) experiment E375: spectroscopy of trans-fermium nuclei p.69-91, 6) experiment E408S: He8 on Pb208 and Bi209 p.92-102, 7) experiment E462: very neutron rich calcium isotopes at N=32, structure of magic Ca54 studied by gamma-spectroscopy with deep inelastic reactions p.103-115, 8) experiment E451: searching for T=D pairing and a new coupling scheme in Pd92 and Ru88 p.116-141, and 9) experiment E404aS: identification of gamma rays in nuclei around the drip-line nucleus Sm130, probing the maximally deformed light rare earth region

  16. Coldwater River NWR Ancillary Bird Observations 2006

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Ancillary bird observations on Coldwater River NWR in 2006 were recorded by local birders. No sampling design was used to generate the observations

  17. Coldwater River NWR Ancillary Bird Observations 2009

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Ancillary bird observations on Coldwater River NWR in 2009 were recorded by local birders. No sampling design was used to generate the observations

  18. Exogam with its ancillary detectors

    Energy Technology Data Exchange (ETDEWEB)

    Theisen, Ch. [CEA Saclay, Dept. d' Astrophysique, de Physique des Particules de Physique Nucleaire et de l' Instrumentation Associee, 91- Gif sur Yvette (France)

    2004-07-01

    The goal of the meeting was to discuss the status of experiments using Exogam and its ancillary detectors. Presentations include details of experiments already run and those in preparation. This document gathers most of the slides presented at the meeting. The results of 7 experiments are described. There are 9 contributions as it follows: 1) presentation of the Vamos spectrometer p.1-15, 2) the Clara (detector) and Prisma (spectrometer) setup: status and perspectives p.16-33, 3) experiment E344aS: shape coexistence near the N=Z line and collective properties of Kr isotopes investigated by low-energy Coulomb excitation p.34-56, 4) experiment E389: study of effective charges at Sm{sup 100} via the nuclear lifetime measurements in Pd{sup 96} and Cd{sup 98} p.57-68, 5) experiment E375: spectroscopy of trans-fermium nuclei p.69-91, 6) experiment E408S: He{sup 8} on Pb{sup 208} and Bi{sup 209} p.92-102, 7) experiment E462: very neutron rich calcium isotopes at N=32, structure of magic Ca{sup 54} studied by gamma-spectroscopy with deep inelastic reactions p.103-115, 8) experiment E451: searching for T=D pairing and a new coupling scheme in Pd{sup 92} and Ru{sup 88} p.116-141, and 9) experiment E404aS: identification of gamma rays in nuclei around the drip-line nucleus Sm{sup 130}, probing the maximally deformed light rare earth region.

  19. Ancillary Testing in Lung Cancer Diagnosis

    OpenAIRE

    William Dubinski; Leighl, Natasha B.; Ming-Sound Tsao; David M. Hwang

    2012-01-01

    The pathologic diagnosis of lung cancer historically has relied primarily on morphologic features of tumors in histologic sections. With the emergence of new targeted therapies, the pathologist is called upon increasingly to provide not only accurate typing of lung cancers, but also to provide prognostic and predictive information, based on a growing number of ancillary tests, that may have significant impact on patient management. This review provides an overview of ancillary tests currently...

  20. AX Tank Farm ancillary equipment study

    International Nuclear Information System (INIS)

    This report examines the feasibility of remediating ancillary equipment associated with the 241-AX Tank Farm at the Hanford Site. Ancillary equipment includes surface structures and equipment, process waste piping, ventilation components, wells, and pits, boxes, sumps, and tanks used to make waste transfers to/from the AX tanks and adjoining tank farms. Two remedial alternatives are considered: (1) excavation and removal of all ancillary equipment items, and (2) in-situ stabilization by grout filling, the 241-AX Tank Farm is being employed as a strawman in engineering studies evaluating clean and landfill closure options for Hanford single-shell tanks. This is one of several reports being prepared for use by the Hanford Tanks Initiative Project to explore potential closure options and to develop retrieval performance evaluation criteria for tank farms

  1. Pilin Vaccination Stimulates Weak Antibody Responses and Provides No Protection in a C57Bl/6 Murine Model of Acute Clostridium difficile Infection

    Science.gov (United States)

    Maldarelli, Grace A; Matz, Hanover; Gao, Si; Chen, Kevin; Hamza, Therwa; Yfantis, Harris G; Feng, Hanping; Donnenberg, Michael S

    2016-01-01

    Clostridium difficile is the leading cause of nosocomial infections in the United States, adding billions of dollars per year to health care costs. A vaccine targeted against the bacterium would be extremely beneficial in decreasing the morbidity and mortality caused by C. difficile-associated disease; a vaccine directed against a colonization factor would hinder the spread of the bacterium as well as prevent disease. Type IV pili (T4Ps) are extracellular appendages composed of protein monomers called pilins. They are involved in adhesion and colonization in a wide variety of bacteria and archaea, and are putative colonization factors in C. difficile. We hypothesized that vaccinating mice with pilins would lead to generation of anti-pilin antibodies, and would protect against C. difficile challenge. We found that immunizing C57Bl/6 mice with various pilins, whether combined or as individual proteins, led to low anti-pilin antibody titers and no protection upon C. difficile challenge. Passive transfer of anti-pilin antibodies led to high serum anti-pilin IgG titers, but to undetectable fecal anti-pilin IgG titers and did not protect against challenge. The low antibody titers observed in these experiments may be due to the particular strain of mice used. Further experiments, possibly with a different animal model of C. difficile infection, are needed to determine if an anti-T4P vaccine would be protective against C. difficile infection. PMID:27375958

  2. Mucosal adhesion properties of the probiotic Lactobacillus rhamnosus GG SpaCBA and SpaFED pilin subunits

    NARCIS (Netherlands)

    Ossowski, von I.; Reunanen, J.; Satokari, R.M.; Vesterlund, S.; Kankainen, M.; Huhtinen, H.; Tynkkynen, S.; Salminen, S.; Vos, de W.M.; Palva, A.

    2010-01-01

    Lactobacillus rhamnosus GG is a well-established Gram-positive probiotic strain, whose health-benefiting properties are in part dependent upon a prolonged residency in the gastrointestinal tract and likely dictated by an adherence to the intestinal mucosa. Previously, we identified two pilus gene cl

  3. Processing and Maturation of the Pilin of the Type IV Secretion System Encoded within the Gonococcal Genetic Island

    NARCIS (Netherlands)

    Jain, Samta; Kahnt, Joerg; van der Does, Chris

    2011-01-01

    The type IV secretion system (T4SS) encoded within the gonococcal genetic island (GGI) of Neisseria gonorrhoeae has homology to the T4SS encoded on the F plasmid. The GGI encodes the putative pilin protein TraA and a serine protease TrbI, which is homologous to the TraF protein of the RP4 plasmid in

  4. Ancillary services available to the orthopedic surgeon.

    Science.gov (United States)

    Bert, Jack M

    2008-01-01

    The delivery of high quality medical services is approaching a crisis situation in the United States. As physician reimbursements decline and overhead increases, orthopedic surgeons must seek additional sources of revenue to remain financially viable and control the quality of medical care that they deliver. The orthopedic surgeon group is well positioned to control its own service lines and deliver excellent patient care as a result. This article reviews the possibilities of multiple types of ancillary service lines available for the orthopedic group practice. PMID:18061762

  5. Reliability Assessment of Coalitions for the Provision of Ancillary Services

    OpenAIRE

    Blank, Marita

    2015-01-01

    The introduction of distributed renewable power units (RPU) changes the operation of electrical power systems. RPU take over tasks of conventional power plants such as energy supply and the provision of ancillary services. The ancillary service provision must be reliable in order to guarantee secure system operations. In this thesis, the RelACs-method is introduced to assess coalitions, i.e. aggregations of RPU, with respect of how reliably they are able to provide ancillary services, particu...

  6. Promoting crystallisation of the Salmonella enteritidis fimbriae 14 pilin SefD using deuterium oxide

    International Nuclear Information System (INIS)

    Highlights: ► The benefits of D2O in screening for crystallisation was explored. ► The crystal structures of the SefD pilin in both H2O and D2O reveal differences. ► Crystallisation improvements are explained by altered interactions in D2O crystals. ► D2O is useful additive in sparse-matrix screening for crystallisation. -- Abstract: The use of heavy water (D2O) as a solvent is commonplace in many spectroscopic techniques for the study of biological macromolecules. A significant deuterium isotope effect exists where hydrogen-bonding is important, such as in protein stability, dynamics and assembly. Here we illustrate the use of D2O in additive screening for the production of reproducible diffraction-quality crystals for the Salmonella enteritidis fimbriae 14 (SEF14) putative tip adhesin, SefD.

  7. Contribution of Individual Ebp Pilus Subunits of Enterococcus faecalis OG1RF to Pilus Biogenesis, Biofilm Formation and Urinary Tract Infection

    Science.gov (United States)

    Sillanpää, Jouko; Chang, Chungyu; Singh, Kavindra V.; Montealegre, Maria Camila; Nallapareddy, Sreedhar R.; Harvey, Barrett R.; Ton-That, Hung; Murray, Barbara E.

    2013-01-01

    The endocarditis and biofilm-associated pilus (Ebp) operon is a component of the core genome of Enterococcus faecalis that has been shown to be important for biofilm formation, adherence to host fibrinogen, collagen and platelets, and in experimental endocarditis and urinary tract infection models. Here, we created single and double deletion mutants of the pilus subunits and sortases; next, by combining western blotting, immunoelectron microscopy, and using ebpR in trans to increase pilus production, we identified EbpA as the tip pilin and EbpB as anchor at the pilus base, the latter attached to cell wall by the housekeeping sortase, SrtA. We also confirmed EbpC and Bps as the major pilin and pilin-specific sortase, respectively, both required for pilus polymerization. Interestingly, pilus length was increased and the number of pili decreased by deleting ebpA, while control overexpression of ebpA in trans restored wild-type levels, suggesting a dual role for EbpA in both initiation and termination of pilus polymerization. We next investigated the contribution of each pilin subunit to biofilm formation and UTI. Significant reduction in biofilm formation was observed with deletion of ebpA or ebpC (P<0.001) while ebpB was found to be dispensable; a similar result was seen in kidney CFUs in experimental UTI (ΔebpA, ΔebpC, P≤0.0093; ΔebpB, non-significant, each vs. OG1RF). Hence, our data provide important structural and functional information about these ubiquitous E. faecalis pili and, based on their demonstrated importance in biofilm and infection, suggest EbpA and EbpC as potential targets for antibody-based therapeutic approaches. PMID:23874774

  8. Illustration of Modern Wind Turbine Ancillary Services

    DEFF Research Database (Denmark)

    Margaris, Ioannis D.; Hansen, Anca Daniela; Sørensen, Poul Ejnar; Hatziargyriou, Nikolaos D.

    2010-01-01

    Increasing levels of wind power penetration in modern power systems has set intensively high standards with respect to wind turbine technology during the last years. Security issues have become rather critical and operation of wind farms as conventional power plants is becoming a necessity as wind...... turbines replace conventional units on the production side. This article includes a review of the basic control issues regarding the capability of the Doubly Fed Induction Generator (DFIG) wind turbine configuration to fulfill the basic technical requirements set by the system operators and contribute to...... power system security. An overview of ancillary services provided by wind turbine technology nowadays is provided, i.e., fault ride-through capability, reactive power supply and frequency-active power control....

  9. Integration of Flexible Consumers in the Ancillary Service Markets

    DEFF Research Database (Denmark)

    Biegel, Benjamin; Westenholz, Mikkel; Hansen, Lars Henrik;

    2014-01-01

    Flexible consumption devices are often able to quickly adjust the power consumption making these devices very well suited as providers of fast ancillary services such as primary and secondary reserves. As these reserves are among the most well-paid ancillary services, it is an interesting idea...... to let an aggregator control a portfolio of flexible consumption devices and sell the accumulated flexibility in the primary and secondary reserve markets. However, two issues make it difficult for a portfolio of consumption devices to provide ancillary services: First, flexible consumption devices only...... have a limited energy capacity and are therefore not able to provide actual energy deliveries. Second, it is often difficult to make an accurate consumption baseline estimate for a portfolio of flexible consumption devices. These two issues do not fit the current regulations for providing ancillary...

  10. Load Participation in Ancillary Services System from An Operator Perspective

    Energy Technology Data Exchange (ETDEWEB)

    Kujawski, Don [PJM, Audubon, PA (United States); Petri, Mark C. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2011-10-25

    Ancillary services as defined by FERC (Order 888) distinguished by response time, duration, frequency. Met when DR has capability to balance supply and demand; and LMP payment to DR is cost effective.

  11. Frequency control ancillary services in large interconnected systems

    OpenAIRE

    Diouf, Edmond

    2013-01-01

    This research focuses on frequency control ancillary services in large interconnected systems. It analyses and assesses possible alternatives for optimal and innovative solutions of major frequency control issues in large interconnected systems within liberalised electricity markets. Possible improvements in the performance of frequency control are identified. A framework of frequency control ancillary services in large interconnected systems by including loads and wind generation is also pro...

  12. Survey of U.S. Ancillary Services Markets

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Zhi [Argonne National Lab. (ANL), Argonne, IL (United States); Levin, Todd [Argonne National Lab. (ANL), Argonne, IL (United States); Conzelmann, Guenter [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-01-01

    In addition to providing energy to end-consumers, power system operators are also responsible for ensuring system reliability. To this end, power markets maintain an array of ancillary services to ensure it is always possible to balance the supply and demand for energy in real-time. A subset of these ancillary services are commonly procured through market-based mechanisms: namely, Regulation, Spinning, and Non-spinning Reserves.

  13. Using OWL-S to annotate services with ancillary behaviour

    OpenAIRE

    Belecheanu, R A; Jacyno, M; Payne, T.

    2004-01-01

    This paper introduces the concept of services with ancillary behaviour and illustrates the use of OWL-S to semantically describe them. The OWL-S syntax used reflects the dynamic and core-function independent nature of ancillary behaviour. The approach is illustrated on the case of a ubiquitous computing system designed to offer care in the home of a cardiac patient. Here one of the challenges is to ensure service availability, team awareness and transaction atomicity. The concept of commitmen...

  14. Options for pricing ancillary services in a deregulated power system

    Science.gov (United States)

    Yamin, Hatim Yahya

    2001-07-01

    GENCOs in restructured systems are compensated for selling energy in the market. In a restructured market, a mechanism is required to entice participants in the market to provide ancillary services and to ensure adequate compensation that would guarantee its economic viability. The ISO controls the dispatch of generation, manages the reliability of the transmission grid, provides open access to the transmission, buys and provides ancillary services as required, coordinates day-ahead, hour-ahead schedules and performs real time balancing of load and generation, settles real time imbalances and ancillary services sales and purchases. The ISO, also, administers congestion management protocols for the transmission grid. Since the ISO does not own any generating units it must ensure that there is enough reserves for maintaining reliability according to FERC regulations, and sufficient unloaded generating capacity for balancing services in a real-time market. The ISO could meet these requirements by creating a competitive market for ancillary services, which are metered and remain unbundled to provide an accurate compensation for each supplier and cost to each consumer, In this study, we give an overview for restructuring and ancillary services in a restructured power marketplace. Also, we discuss the effect of GENCOs' actions in the competitive energy and ancillary service markets. In addition, we propose an auction market design for hedging ancillary service costs in California market. Furthermore, we show how to include the n-1 and voltage contingencies in security constrained unit commitment. Finally, we present two approaches for GENCOs' unit commitment in a restructured power market; one is based on game theory and the other is based on market price forecasting. In each of the two GENCOs' unit commitment approaches, we discuss the GENCOs' optimal bidding strategies in energy and ancillary service markets to maximize the GENCOs' profit.

  15. Ancillary study management systems: a review of needs

    Directory of Open Access Journals (Sweden)

    Nelson Elizabeth K

    2013-01-01

    Full Text Available Abstract Background The valuable clinical data, specimens, and assay results collected during a primary clinical trial or observational study can enable researchers to answer additional, pressing questions with relatively small investments in new measurements. However, management of such follow-on, “ancillary” studies is complex. It requires coordinating across institutions, sites, repositories, and approval boards, as well as distributing, integrating, and analyzing diverse data types. General-purpose software systems that simplify the management of ancillary studies have not yet been explored in the research literature. Methods We have identified requirements for ancillary study management primarily as part of our ongoing work with a number of large research consortia. These organizations include the Center for HIV/AIDS Vaccine Immunology (CHAVI, the Immune Tolerance Network (ITN, the HIV Vaccine Trials Network (HVTN, the U.S. Military HIV Research Program (MHRP, and the Network for Pancreatic Organ Donors with Diabetes (nPOD. We also consulted with researchers at a range of other disease research organizations regarding their workflows and data management strategies. Lastly, to enhance breadth, we reviewed process documents for ancillary study management from other organizations. Results By exploring characteristics of ancillary studies, we identify differentiating requirements and scenarios for ancillary study management systems (ASMSs. Distinguishing characteristics of ancillary studies may include the collection of additional measurements (particularly new analyses of existing specimens; the initiation of studies by investigators unaffiliated with the original study; cross-protocol data pooling and analysis; pre-existing participant consent; and pre-existing data context and provenance. For an ASMS to address these characteristics, it would need to address both operational requirements (e.g., allocating existing specimens and data

  16. Ancillary spending : Working Paper No. 3.2.1

    Energy Technology Data Exchange (ETDEWEB)

    Lasota, M.; McCracken, M.C.; Zanasi, L. [Informetrica Ltd., Ottawa, ON (Canada)

    2002-04-01

    This study discussed the ancillary spending that would be incurred by the Yukon Government as a result of the Alaska Highway Pipeline Project. Ancillary spending refers to investment that is needed to facilitate pipeline construction but is not directly related to the pipeline. It includes investment in roads and highways, water treatment, sewage and solid waste, air transportation, rail transportation (including the White Pass and the Canadian Arctic Railway), port development, schools, health services, and jails. It was determined that ancillary expenditures to the Yukon Government excluding health and correctional services is estimated at $6.95 to $7.85 million in pre-pipeline construction. During the 3 years of pipeline construction and the first 3 years of pipeline operation, the ancillary spending is not expected to be greater than $21.7 million. Ancillary spending includes the need to repair existing facilities and infrastructures after the pipeline is completed. This will provide employment for a variety of skilled people including engineers and trades people. Other developments associated with the AHPP may include gas field and mining development as well as developments in local gas and electricity distribution. 4 refs., 1 tab.

  17. Medical Researchers' Ancillary Care Obligations: The Relationship-Based Approach.

    Science.gov (United States)

    Olson, Nate W

    2016-06-01

    In this article, I provide a new account of the basis of medical researchers' ancillary care obligations. Ancillary care in medical research, or medical care that research participants need but that is not required for the validity or safety of a study or to redress research injuries, is a topic that has drawn increasing attention in research ethics over the last ten years. My view, the relationship-based approach, improves on the main existing theory, Richardson and Belsky's 'partial-entrustment model', by avoiding its problematic restriction on the scope of health needs for which researchers could be obligated to provide ancillary care. Instead, it grounds ancillary care obligations in a wide range of morally relevant features of the researcher-participant relationship, including the level of engagement between researchers and participants, and weighs these factors against each other. I argue that the level of engagement, that is, the duration and intensity of interactions, between researchers and participants matters for ancillary care because of its connection to the meaningfulness of a relationship, and I suggest that other morally relevant features can be grounded in researchers' role obligations. PMID:26424512

  18. Ancillary spending : Working Paper No. 3.2.1

    International Nuclear Information System (INIS)

    This study discussed the ancillary spending that would be incurred by the Yukon Government as a result of the Alaska Highway Pipeline Project. Ancillary spending refers to investment that is needed to facilitate pipeline construction but is not directly related to the pipeline. It includes investment in roads and highways, water treatment, sewage and solid waste, air transportation, rail transportation (including the White Pass and the Canadian Arctic Railway), port development, schools, health services, and jails. It was determined that ancillary expenditures to the Yukon Government excluding health and correctional services is estimated at $6.95 to $7.85 million in pre-pipeline construction. During the 3 years of pipeline construction and the first 3 years of pipeline operation, the ancillary spending is not expected to be greater than $21.7 million. Ancillary spending includes the need to repair existing facilities and infrastructures after the pipeline is completed. This will provide employment for a variety of skilled people including engineers and trades people. Other developments associated with the AHPP may include gas field and mining development as well as developments in local gas and electricity distribution. 4 refs., 1 tab

  19. Ancillary effects of selected acid deposition control policies

    Energy Technology Data Exchange (ETDEWEB)

    Moe, R.J.; Lyke, A.J.; Nesse, R.J.

    1986-08-01

    NAPAP is examining a number of potential ways to reduce the precursors (sulfur dioxide and nitrogen oxides) to acid deposition. However, the policies to reduce acid deposition will have other physical, biological and economic effects unrelated to acid deposition. For example, control policies that reduce sulfur dioxide emissions may also increase visibility. The effects of an acid deposition policy that are unrelated to acid deposition are referred to as ''ancillary'' effects. This reserch identifies and characterizes the principle physical and economic ancillary effects associated with acid deposition control and mitigation policies. In this study the ancillary benefits associated with four specific acid deposition policy options were investigated. The four policy options investigated are: (1) flue gas desulfurization, (2) coal blending or switching, (3) reductions in automobile emissions of NO/sub x/, and (4) lake liming. Potential ancillary benefits of each option were identified and characterized. Particular attention was paid to the literature on economic valuation of potential ancillary effects.

  20. The evolving design of RTO ancillary service markets

    International Nuclear Information System (INIS)

    Although the markets for ancillary services at the North American Independent System Operators are often structured in quite different ways there is an emerging set of core design elements that represent a rough consensus as to what the optimal design configuration for ancillary services should be, albeit with some regional variation. This paper looks back at how the design of ancillary services markets has recently evolved to put this development in context. Thereafter it examines the methods by which ancillary services are procured by highlighting the procurement practices at a number of different Independent System Operators, principally those in California, New York, New England, Texas and the PJM Interconnection, in an attempt to tease out the remaining reasons why the ancillary service markets are still so different. This is important as there are many innovations that are not rooted in regional differences but reflect genuine technical advances and economic efficiency gains and can be replicated across other ISOs to produce more efficient designs, greater reliability and lower costs. (author)

  1. Shared antigenicity and immunogenicity of type 4 pilins expressed by Pseudomonas aeruginosa, Moraxella bovis, Neisseria gonorrhoaea, Dichelobacter nodosus, and Vibrio cholerae.

    Science.gov (United States)

    Patel, P; Marrs, C F; Mattick, J S; Ruehl, W W; Taylor, R K; Koomey, M

    1991-12-01

    Immunoblotting with polyclonal rabbit antibodies raised against pilins expressed by Pseudomonas aeruginosa, Moraxella bovis, Neisseria gonorrhoeae, Dichelobacter nodosus, and Vibrio cholerae was used to demonstrate that these polypeptides display conserved antigenic and, in most cases, immunogenic determinants. These determinants appear to be localized to the highly homologous amino-terminal domains (residues 1 to 25). PMID:1682267

  2. Loads Providing Ancillary Services: Review of International Experience

    Energy Technology Data Exchange (ETDEWEB)

    Heffner, Grayson; Goldman, Charles; Kintner-Meyer, Michael

    2007-05-01

    In this study, we examine the arrangements for and experiences of end-use loads providing ancillary services (AS) in five electricity markets: Australia, the United Kingdom (UK), the Nordic market, and the ERCOT and PJM markets in the United States. Our objective in undertaking this review of international experience was to identify specific approaches or market designs that have enabled customer loads to effectively deliver various ancillary services (AS) products. We hope that this report will contribute to the ongoing discussion in the U.S. and elsewhere regarding what institutional and technical developments are needed to ensure that customer loads can meaningfully participate in all wholesale electricity markets.

  3. Comparative molecular docking analysis of cytoplasmic dynein light chain DYNLL1 with pilin to explore the molecular mechanism of pathogenesis caused by Pseudomonas aeruginosa PAO.

    Directory of Open Access Journals (Sweden)

    Samina Kausar

    Full Text Available Cytoplasmic dynein light chain 1 (DYNLL1 is a component of large protein complex, which is implicated in cargo transport processes, and is known to interact with many cellular and viral proteins through its short consensus motif (K/RXTQT. Still, it remains to be explored that bacterial proteins also exhibit similar recognition sequences to make them vulnerable to host defense mechanism. We employed multiple docking protocols including AUTODOCK, PatchDock, ZDOCK, DOCK/PIERR and CLUSPRO to explore the DYNLL1 and Pilin interaction followed by molecular dynamics simulation assays. Subsequent structural comparison of the predicted binding site for DYNLL1-Pilin complex against the experimentally verified DYNLL1 binding partners was performed to cross check the residual contributions and to determine the binding mode. On the basis of in silico analysis, here we describe a novel interaction of DYNLL1 and receptor binding domain of Pilin (the main protein constituent of bacterial type IV Pili of gram negative bacteria Pseudomonas aeruginosa (PAO, which is the third most common nosocomial pathogen associated with the life-threatening infections. Evidently, our results underscore that Pilin specific motif (KSTQD exhibits a close structural similarity to that of Vaccinia virus polymerase, P protein Rabies and P protein Mokola viruses. We speculate that binding of DYNLL1 to Pilin may trigger an uncontrolled inflammatory response of the host immune system during P. aeruginosa chronic infections thereby opening a new pioneering area to investigate the role of DYNLL1 in gram negative bacterial infections other than viral infections. Moreover, by manifesting a strict correspondence between sequence and function, our study anticipates a novel drug target site to control the complications caused by P. aeruginosa infections.

  4. Improving recombinant Rubisco biogenesis, plant photosynthesis and growth by coexpressing its ancillary RAF1 chaperone.

    Science.gov (United States)

    Whitney, Spencer M; Birch, Rosemary; Kelso, Celine; Beck, Jennifer L; Kapralov, Maxim V

    2015-03-17

    Enabling improvements to crop yield and resource use by enhancing the catalysis of the photosynthetic CO2-fixing enzyme Rubisco has been a longstanding challenge. Efforts toward realization of this goal have been greatly assisted by advances in understanding the complexities of Rubisco's biogenesis in plastids and the development of tailored chloroplast transformation tools. Here we generate transplastomic tobacco genotypes expressing Arabidopsis Rubisco large subunits (AtL), both on their own (producing tob(AtL) plants) and with a cognate Rubisco accumulation factor 1 (AtRAF1) chaperone (producing tob(AtL-R1) plants) that has undergone parallel functional coevolution with AtL. We show AtRAF1 assembles as a dimer and is produced in tob(AtL-R1) and Arabidopsis leaves at 10-15 nmol AtRAF1 monomers per square meter. Consistent with a postchaperonin large (L)-subunit assembly role, the AtRAF1 facilitated two to threefold improvements in the amount and biogenesis rate of hybrid L8(A)S8(t) Rubisco [comprising AtL and tobacco small (S) subunits] in tob(AtL-R1) leaves compared with tob(AtL), despite >threefold lower steady-state Rubisco mRNA levels in tob(AtL-R1). Accompanying twofold increases in photosynthetic CO2-assimilation rate and plant growth were measured for tob(AtL-R1) lines. These findings highlight the importance of ancillary protein complementarity during Rubisco biogenesis in plastids, the possible constraints this has imposed on Rubisco adaptive evolution, and the likely need for such interaction specificity to be considered when optimizing recombinant Rubisco bioengineering in plants. PMID:25733857

  5. 42 CFR 414.40 - Coding and ancillary policies.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Coding and ancillary policies. 414.40 Section 414.40 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICARE PROGRAM PAYMENT FOR PART B MEDICAL AND OTHER HEALTH SERVICES Physicians and...

  6. 77 FR 25105 - Reporting of Ancillary Airline Passenger Revenues

    Science.gov (United States)

    2012-04-27

    ... wheelchairs and scooters used by passengers with disabilities. See 76 FR 41726. You may review comments to... Office of the Secretary 14 CFR Parts 234 and 241 RIN 2139-AA13 Reporting of Ancillary Airline Passenger... (NPRM) issued on July 15, 2011. The NPRM proposed changes regarding reporting of airline...

  7. Structure of Streptococcus agalactiae tip pilin GBS104: a model for GBS pili assembly and host interactions

    Energy Technology Data Exchange (ETDEWEB)

    Krishnan, Vengadesan [UNESCO Regional Centre for Biotechnology (RCB), Gurgaon 122 016, Haryana (India); Dwivedi, Prabhat [University of Texas Health Science Center, Houston, TX 77030 (United States); Kim, Brandon J. [San Diego State University, 5500 Campanile Drive, San Diego, CA 92182 (United States); Samal, Alexandra; Macon, Kevin [University of Alabama at Birmingham, Birmingham, AL 35294 (United States); Ma, Xin; Mishra, Arunima [University of Texas Health Science Center, Houston, TX 77030 (United States); Doran, Kelly S. [San Diego State University, 5500 Campanile Drive, San Diego, CA 92182 (United States); Ton-That, Hung [University of Texas Health Science Center, Houston, TX 77030 (United States); Narayana, Sthanam V. L., E-mail: narayana@uab.edu [University of Alabama at Birmingham, Birmingham, AL 35294 (United States); UNESCO Regional Centre for Biotechnology (RCB), Gurgaon 122 016, Haryana (India)

    2013-06-01

    The crystal structure of a 75 kDa central fragment of GBS104, a tip pilin from the 2063V/R strain of Streptococcus agalactiae (group B streptococcus; GBS), is reported. The crystal structure of a 75 kDa central fragment of GBS104, a tip pilin from the 2063V/R strain of Streptococcus agalactiae (group B streptococcus; GBS), is reported. In addition, a homology model of the remaining two domains of GBS104 was built and a model of full-length GBS104 was generated by combining the homology model (the N1 and N4 domains) and the crystal structure of the 75 kDa fragment (the N2 and N3 domains). This rod-shaped GBS104 model is constructed of three IgG-like domains (the N1, N2 and N4 domains) and one vWFA-like domain (the N3 domain). The N1 and N2 domains of GBS104 are assembled with distinct and remote segments contributed by the N- and C-termini. The metal-binding site in the N3 domain of GBS104 is in the closed/low-affinity conformation. Interestingly, this domain hosts two long arms that project away from the metal-binding site. Using site-directed mutagenesis, two cysteine residues that lock the N3 domain of GBS104 into the open/high-affinity conformation were introduced. Both wild-type and disulfide-locked recombinant proteins were tested for binding to extracellular matrix proteins such as collagen, fibronectin, fibrinogen and laminin, and an increase in fibronectin binding affinity was identified for the disulfide-locked N3 domain, suggesting that induced conformational changes may play a possible role in receptor binding.

  8. Crystallization and initial crystallographic analysis of AafA: the major adhesive subunit of the enteroaggregative Escherichia coli AAF/II pilus

    International Nuclear Information System (INIS)

    The Enteroaggregative Escherichia coli AAF/II pilus plays an important role in the attachment to and invasion of the host during the initial stages of colonization. Here, the major adhesive subunit of AAF/II has been crystallized at pH 3.4 and diffraction data have been collected to 2.1 Å resolution. AafA is the major adhesive pilin subunit of the aggregative adherence fimbriae (AAF) from enteroaggregative Escherichia coli, which play an important role by attaching to the host cells during the initial phase of bacterial colonization and invasion. AafA has been crystallized at pH 3.4 and diffraction data have been collected to 2.1 Å resolution. Molecular replacement was unsuccessful and selenomethionine-substituted protein and heavy-atom derivatives are being prepared for phasing

  9. An ancillary pumping system for the APS vacuum system

    Energy Technology Data Exchange (ETDEWEB)

    Walters, D.; Noonan, J.; Gagliano, J. [and others

    1997-06-01

    An ancillary pumping system has been designed and installed in the Advanced Photon Source (APS) storage ring. This vacuum system has the ability to pump sectors of the storage ring down from room pressure to ultra-high vacuum (UHV). The ancillary system is a {open_quotes}dry{close_quotes} system that uses a combination of turbomolecular pumps and oil-free roughing pumps. The benefits of this system are the reduction of equipment needed for in-tunnel maintenance, essential for the operation of a UHV storage ring; rapid response to vacuum emergencies and a guard to accidental exposures to hydrocarbon contamination. The operational logic and the pump interlock and controls are described.

  10. Quantum Correlations Reduce Classical Correlations with Ancillary Systems

    Institute of Scientific and Technical Information of China (English)

    LUO Shun-Long; LI Nan

    2010-01-01

    @@ We illustrate the dichotomy of classical/quantum correlations by virtue of monogamy.More precisely,we show that correlations in a bipartite state are classical if and only if each party of the state can be perfectly correlated with other ancillary systems.In particular,this means that if there are quantum correlations between two parties,then the classical(as well as quantum)correlating capabilities of the two parties with other systems have to be strictly reduced.

  11. Unanticipated Consequences: Thinking About Ancillary Benefits and Costs of Greenhouse Gas Emissions Mitigation

    Energy Technology Data Exchange (ETDEWEB)

    Edmonds, James A.

    2005-03-31

    Recently there has been interest in the “ancillary benefits” of potential policies to address climate change. Ancillary benefits occur whenever a policy to address climate change also results in a reduction in some conventional pollutant. Framing the problem in terms of ancillary benefits is too narrow. In general implementation of any policy can have consequences for unpriced environmental externalities that extend beyond the original target of the policy. These ancillary consequences can be either positive, negative, or mixed. This is the inevitable implication of undertaking policy in a non-linear world. In this essay we explore some of the ancillary benefits and costs of addressing climate change.

  12. The N-Terminal GYPSY Motif Is Required for Pilin-Specific Sortase SrtC1 Functionality in Lactobacillus rhamnosus Strain GG.

    Science.gov (United States)

    Douillard, François P; Rasinkangas, Pia; Bhattacharjee, Arnab; Palva, Airi; de Vos, Willem M

    2016-01-01

    Predominantly identified in pathogenic Gram-positive bacteria, sortase-dependent pili are also found in commensal species, such as the probiotic-marketed strain Lactobacillus rhamnosus strain GG. Pili are typically associated with host colonization, immune signalling and biofilm formation. Comparative analysis of the N-terminal domains of pilin-specific sortases from various piliated Gram-positive bacteria identified a conserved motif, called GYPSY, within the signal sequence. We investigated the function and role of the GYPSY residues by directed mutagenesis in homologous (rod-shaped) and heterologous (coccoid-shaped) expression systems for pilus formation. Substitutions of some of the GYPSY residues, and more specifically the proline residue, were found to have a direct impact on the degree of piliation of Lb. rhamnosus GG. The present findings uncover a new signalling element involved in the functionality of pilin-specific sortases controlling the pilus biogenesis of Lb. rhamnosus GG and related piliated Gram-positive species. PMID:27070897

  13. The N-Terminal GYPSY Motif Is Required for Pilin-Specific Sortase SrtC1 Functionality in Lactobacillus rhamnosus Strain GG

    Science.gov (United States)

    Douillard, François P.; Rasinkangas, Pia; Bhattacharjee, Arnab; Palva, Airi; de Vos, Willem M.

    2016-01-01

    Predominantly identified in pathogenic Gram-positive bacteria, sortase-dependent pili are also found in commensal species, such as the probiotic-marketed strain Lactobacillus rhamnosus strain GG. Pili are typically associated with host colonization, immune signalling and biofilm formation. Comparative analysis of the N-terminal domains of pilin-specific sortases from various piliated Gram-positive bacteria identified a conserved motif, called GYPSY, within the signal sequence. We investigated the function and role of the GYPSY residues by directed mutagenesis in homologous (rod-shaped) and heterologous (coccoid-shaped) expression systems for pilus formation. Substitutions of some of the GYPSY residues, and more specifically the proline residue, were found to have a direct impact on the degree of piliation of Lb. rhamnosus GG. The present findings uncover a new signalling element involved in the functionality of pilin-specific sortases controlling the pilus biogenesis of Lb. rhamnosus GG and related piliated Gram-positive species. PMID:27070897

  14. The N-Terminal GYPSY Motif Is Required for Pilin-Specific Sortase SrtC1 Functionality in Lactobacillus rhamnosus Strain GG

    OpenAIRE

    Douillard, François P.; Rasinkangas, Pia; Bhattacharjee, Arnab; Palva, Airi; de Vos, Willem M

    2016-01-01

    Predominantly identified in pathogenic Gram-positive bacteria, sortase-dependent pili are also found in commensal species, such as the probiotic-marketed strain Lactobacillus rhamnosus strain GG. Pili are typically associated with host colonization, immune signalling and biofilm formation. Comparative analysis of the N-terminal domains of pilin-specific sortases from various piliated Gram-positive bacteria identified a conserved motif, called GYPSY, within the signal sequence. We investigated...

  15. Optimal generator bidding strategies for power and ancillary services

    Science.gov (United States)

    Morinec, Allen G.

    As the electric power industry transitions to a deregulated market, power transactions are made upon price rather than cost. Generator companies are interested in maximizing their profits rather than overall system efficiency. A method to equitably compensate generation providers for real power, and ancillary services such as reactive power and spinning reserve, will ensure a competitive market with an adequate number of suppliers. Optimizing the generation product mix during bidding is necessary to maximize a generator company's profits. The objective of this research work is to determine and formulate appropriate optimal bidding strategies for a generation company in both the energy and ancillary services markets. These strategies should incorporate the capability curves of their generators as constraints to define the optimal product mix and price offered in the day-ahead and real time spot markets. In order to achieve such a goal, a two-player model was composed to simulate market auctions for power generation. A dynamic game methodology was developed to identify Nash Equilibria and Mixed-Strategy Nash Equilibria solutions as optimal generation bidding strategies for two-player non-cooperative variable-sum matrix games with incomplete information. These games integrated the generation product mix of real power, reactive power, and spinning reserve with the generators's capability curves as constraints. The research includes simulations of market auctions, where strategies were tested for generators with different unit constraints, costs, types of competitors, strategies, and demand levels. Studies on the capability of large hydrogen cooled synchronous generators were utilized to derive useful equations that define the exact shape of the capability curve from the intersections of the arcs defined by the centers and radial vectors of the rotor, stator, and steady-state stability limits. The available reactive reserve and spinning reserve were calculated given a

  16. Demand Response Resources for Energy and Ancillary Services (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Hummon, M.

    2014-04-01

    Demand response (DR) resources present a potentially important source of grid flexibility particularly on future systems with high penetrations of variable wind an solar power generation. However, DR in grid models is limited by data availability and modeling complexity. This presentation focuses on the co-optimization of DR resources to provide energy and ancillary services in a production cost model of the Colorado test system. We assume each DR resource can provide energy services by either shedding load or shifting its use between different times, as well as operating

  17. Ancillary procedure for early diagnosis of brain damage in children

    International Nuclear Information System (INIS)

    CT scan of the head was performed on 14 patients with cerebral palsy, 16 with central coordination disorders, and 16 controls, and findings showing cerebral atrophy and enlargement of the cerebral ventricle were obtained in cases both of cerebral palsy and of central coordination disorders. To objectify these findings, 10 items were selected and evaluated according to 4 grades (0 - 3) and were compared. As a result, it was concluded that CT scan is an excellent ancillary procedure for early diagnosis of brain damages. (Tsunoda, M.)

  18. Ancillary services and optimal household energy management with photovoltaic production

    International Nuclear Information System (INIS)

    This article presents a project designed to increase the monetary value of photovoltaic (PV) solar production for residential applications. To contribute to developing new functionalities for this type of PV system and an efficient control system for optimising its operation, this article explains how the proposed system could contract to provide ancillary services, particularly the supply of active power services. This provision of service by a PV-based system for domestic applications, not currently available, has prompted a market design proposal related to the distribution system. The mathematical model for calculating the system's optimal operation (sources, load and exchanges of power with the grid) results in a linear mix integer optimisation problem in which the objective is to maximise the profits achieved by taking part in the electricity market. Our approach is illustrated in a case study. PV producers could gain by taking part in the markets for balancing power or ancillary services despite the negative impact on profit of several types of uncertainty, notably the intermittent nature of the PV source. (author)

  19. Ancillary services and optimal household energy management with photovoltaic production

    International Nuclear Information System (INIS)

    This article presents a project designed to increase the monetary value of photovoltaic (PV) solar production for residential applications. To contribute to developing new functionalities for this type of PV system and an efficient control system for optimising its operation, this article explains how the proposed system could contract to provide ancillary services, particularly the supply of active power services. This provision of service by a PV-based system for domestic applications, not currently available, has prompted a market design proposal related to the distribution system. The mathematical model for calculating the system's optimal operation (sources, load and exchanges of power with the grid) results in a linear mix integer optimisation problem in which the objective is to maximise the profits achieved by taking part in the electricity market. Our approach is illustrated in a case study. PV producers could gain by taking part in the markets for balancing power or ancillary services despite the negative impact on profit of several types of uncertainty, notably the intermittent nature of the PV source.

  20. Exogam with Vamos, Tiara and other ancillary detectors

    Energy Technology Data Exchange (ETDEWEB)

    Lewitowicz, M.; Olivier, L.; Savajols, H.; Catford, W.; Raine, B.; Oliveira, F. de; Perru, O.; Podolyak, Z.; Redon, N.; Bouchez, E.; Simenel, C.; Stanoiu, M.; Lemmon, R.; Rubio, B.; Obertelli, A.; Cederwall, B.; Chapman, R.; Korten, W.; Rubio Barroso, B

    2003-07-01

    The aim of this workshop was to discuss the status of experiments at GANIL facility using Exogam with Vamos, Tiara and other ancillary detectors. This document gathers most of the slides that were presented at the workshop, it concerns 8 presentations: 1) the status of Spiral and Spiral-II, 2) the status of Tiara (Tiara array is used for the study of nuclear transfer reactions with radioactive beams in inverse kinematics), 3) data acquisition for the ancillary detectors, 4) the identification of gamma-ray in nuclei around Sm{sup 130}: probing the maximally deformed light rare earth region, 5) the Coulomb excitation of radioactive krypton beams (Kr{sup 76}, Kr{sup 74}), 6) the influence of weakly bound neutrons on fusion around the Coulomb barrier, 7) single particle transfer on doubly-magic Ni{sup 56}, and 8) the study of N=16 for neutron rich nuclei with Ne{sup 26}(d,p)Ne{sup 27} transfer reaction.

  1. Enhancing the capability of controlling quantum systems via ancillary systems

    Institute of Scientific and Technical Information of China (English)

    Zhang Ming; Gao Da-Yuan; Dai Hong-Yi; Xie Hong-Wei; Hu De-Wen

    2007-01-01

    This paper explores the potential of controlling quantum systems by introducing ancillary systems and then performing unitary operation on the resulting composite systems. It generalizes the concept of pure state controllability for quantum systems and establishes the link between the operator controllability of the composite system and the generalized pure state controllability of its subsystem. It is constructively demonstrated that if a composite quantum system can be transferred between any pair of orthonormal pure vectors, then its subsystem is generalized pure-state controllable. Furthermore, the unitary operation and the coherent control can be concretely given to transfer the system from an initial state to the target state. Therefore, these properties may be potentially applied in quantum information,such as manipulating multiple quantum bits and creating entangled pure states. A concrete example has been given to illustrate that a maximally entangled pure state of a quantum system can be generated by introducing an ancillary system and performing open-loop coherent control on the resulting composite system.

  2. National Ignition Facility sub-system design requirements ancillary systems SSDR 1.5.6

    Energy Technology Data Exchange (ETDEWEB)

    Spann, J.; Reed, R.; VanArsdall, P.; Bliss, E.

    1996-09-01

    This System Design Requirement document establishes the performance, design, development, and test requirements for the Ancillary Systems, which is part of the NIF Integrated Computer Control System (ICCS).

  3. 17 CFR 240.3b-15 - Definition of ancillary portfolio management securities activities.

    Science.gov (United States)

    2010-04-01

    ... portfolio management securities activities. 240.3b-15 Section 240.3b-15 Commodity and Securities Exchanges... ancillary portfolio management securities activities. (a) The term ancillary portfolio management securities... of incidental trading activities for portfolio management purposes; and (3) Are limited to...

  4. 47 CFR 90.317 - Fixed ancillary signaling and data transmissions.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Fixed ancillary signaling and data transmissions. 90.317 Section 90.317 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Authorization in the Band 470-512 MHz (UHF-TV Sharing) § 90.317 Fixed ancillary...

  5. Effective Ancillary Services Market Designs on High Wind Power Penetration Systems: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Ela, E.; Kirby, B.; Navid, N.; Smith, J. C.

    2011-12-01

    This paper focuses on how the ancillary service market designs are implemented and how they may require changes on systems with greater penetrations of variable renewable energy suppliers, in particular wind power. Ancillary services markets have been developed in many of the restructured power system regions throughout the world. Ancillary services include the services that support the provision of energy to support power system reliability. The ancillary services markets are tied tightly to the design of the energy market and to the physics of the system and therefore careful consideration of power system economics and engineering must be considered in their design. This paper focuses on how the ancillary service market designs are implemented and how they may require changes on systems with greater penetrations of variable renewable energy suppliers, in particular wind power.

  6. Sequence analyses of fimbriae subunit FimA proteins on Actinomyces naeslundii genospecies 1 and 2 and Actinomyces odontolyticus with variant carbohydrate binding specificities

    Directory of Open Access Journals (Sweden)

    Persson Karina

    2006-05-01

    Full Text Available Abstract Background Actinomyces naeslundii genospecies 1 and 2 express type-2 fimbriae (FimA subunit polymers with variant Galβ binding specificities and Actinomyces odontolyticus a sialic acid specificity to colonize different oral surfaces. However, the fimbrial nature of the sialic acid binding property and sequence information about FimA proteins from multiple strains are lacking. Results Here we have sequenced fimA genes from strains of A.naeslundii genospecies 1 (n = 4 and genospecies 2 (n = 4, both of which harboured variant Galβ-dependent hemagglutination (HA types, and from A.odontolyticus PK984 with a sialic acid-dependent HA pattern. Three unique subtypes of FimA proteins with 63.8–66.4% sequence identity were present in strains of A. naeslundii genospecies 1 and 2 and A. odontolyticus. The generally high FimA sequence identity (>97.2% within a genospecies revealed species specific sequences or segments that coincided with binding specificity. All three FimA protein variants contained a signal peptide, pilin motif, E box, proline-rich segment and an LPXTG sorting motif among other conserved segments for secretion, assembly and sorting of fimbrial proteins. The highly conserved pilin, E box and LPXTG motifs are present in fimbriae proteins from other Gram-positive bacteria. Moreover, only strains of genospecies 1 were agglutinated with type-2 fimbriae antisera derived from A. naeslundii genospecies 1 strain 12104, emphasizing that the overall folding of FimA may generate different functionalities. Western blot analyses with FimA antisera revealed monomers and oligomers of FimA in whole cell protein extracts and a purified recombinant FimA preparation, indicating a sortase-independent oligomerization of FimA. Conclusion The genus Actinomyces involves a diversity of unique FimA proteins with conserved pilin, E box and LPXTG motifs, depending on subspecies and associated binding specificity. In addition, a sortase independent

  7. Transactive Control and Coordination of Distributed Assets for Ancillary Services

    Energy Technology Data Exchange (ETDEWEB)

    Subbarao, Krishnappa; Fuller, Jason C.; Kalsi, Karanjit; Somani, Abhishek; Pratt, Robert G.; Widergren, Steven E.; Chassin, David P.

    2013-09-18

    The need to diversify energy supplies, the need to mitigate energy-related environmental impact, and the entry of electric vehicles in large numbers present challenges and opportunities to power system professionals. Wind and solar power provide many benefits, and to reap the benefits the resulting increased variability—forecasted as well as unforecasted—should be addressed. Demand resources are receiving increasing attention as one means of providing the grid balancing services. Control and coordination of a large number (~millions) of distributed smart grid assets requires innovative approaches. One such is transactive control and coordination (TC2)—a distributed, agent-based incentive and control system. The TC2 paradigm is to create a market system with the following characteristics: • Participation should be entirely voluntary. • The participant decides at what price s/he is willing to participate. • The bids and responses are automated. Such an approach has been developed and demonstrated by Pacific Northwest National Laboratory for energy markets. It is the purpose of this project to develop a similar approach for ancillary services. In this report, the following ancillary services are considered: • spinning reserve • ramping • regulation. These services are to be provided by the following devices: • refrigerators • water heaters • clothes dryers • variable speed drives. The important results are summarized below: The regulation signal can be divided into an energy-neutral high frequency component and a low frequency component. The high frequency component is particularly well suited for demand resources. The low frequency component, which carries energy non-neutrality, can be handled by a combination of generators and demand resources. An explicit method for such a separation is obtained from an exponentially weighted moving average filter. Causal filters (i.e., filters that process only present and past values of a signal

  8. 78 FR 46177 - Third-Party Provision of Ancillary Services; Accounting and Financial Reporting for New Electric...

    Science.gov (United States)

    2013-07-30

    ... Third-Party Provision of Ancillary Services; Accounting and Financial Reporting for New Electric Storage...-Party Provision of Ancillary Services; Accounting and Financial Reporting for New Electric Storage... services. \\6\\ Third-Party Provision of Ancillary Services; Accounting and Financial Reporting for...

  9. 77 FR 40413 - Third-Party Provision of Ancillary Services; Accounting and Financial Reporting for New Electric...

    Science.gov (United States)

    2012-07-09

    ... 101 Third-Party Provision of Ancillary Services; Accounting and Financial Reporting for New Electric... 101 Third-Party Provision of Ancillary Services; Accounting and Financial Reporting for New Electric... jurisdiction. \\2\\ Third-Party Provision of Ancillary Services; Accounting and Financial Reporting for...

  10. Commercial Building Loads Providing Ancillary Services in PJM

    Energy Technology Data Exchange (ETDEWEB)

    MacDonald, Jason; Kiliccote, Sila; Boch, Jim; Chen, Jonathan; Nawy, Robert

    2014-06-27

    The adoption of low carbon energy technologies such as variable renewable energy and electric vehicles, coupled with the efficacy of energy efficiency to reduce traditional base load has increased the uncertainty inherent in the net load shape. Handling this variability with slower, traditional resources leads to inefficient system dispatch, and in some cases may compromise reliability. Grid operators are looking to future energy technologies, such as automated demand response (DR), to provide capacity-based reliability services as the need for these services increase. While DR resources are expected to have the flexibility characteristics operators are looking for, demonstrations are necessary to build confidence in their capabilities. Additionally, building owners are uncertain of the monetary value and operational burden of providing these services. To address this, the present study demonstrates the ability of demand response resources providing two ancillary services in the PJM territory, synchronous reserve and regulation, using an OpenADR 2.0b signaling architecture. The loads under control include HVAC and lighting at a big box retail store and variable frequency fan loads. The study examines performance characteristics of the resource: the speed of response, communications latencies in the architecture, and accuracy of response. It also examines the frequency and duration of events and the value in the marketplace which can be used to examine if the opportunity is sufficient to entice building owners to participate.

  11. Capabilities and costs for ancillary services provision by wind power plants. Deliverable D 3.1

    DEFF Research Database (Denmark)

    Faiella, Mariano; Hennig, Tobias; Cutululis, Nicolaos Antonio; Van Hulle, Frans

    This report is the deliverable of the third work package of the REserviceS project and describes the technical options and related costs for the provision of ancillary services specifically from wind energy technologies. It is focused on the set of ancillary services defined in the previous work...... package 2, shown in table 1 below. The information from this deliverable will be used as input to the case studies in subsequent work packages, which are expected to provide additional insights to the actual provision of ancillary services in transmission and distribution networks....

  12. Trace Metal and Ancillary Data in Puget Sound, 1980 - 1986 (NODC Accession 9100153)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In first of three data reports on the trace metal and ancillary data in Puget Sound and its watershed (Paulson et al., 1991a), all water column, sediment, and...

  13. EX1202L3 Dive02 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1202L3: Gulf of Mexico...

  14. Ocean Surface Topography Mission (OSTM) /Jason-2: Ancillary Files (NODC Accession 0044982)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This accession contains the data descriptions for the OSTM/Jason-2 Ancillary data files, which is served through the NOAA/NESDIS Comprehensive Large Array-data...

  15. EX1504L4 Dive05 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L4: Campaign to...

  16. EX1504L4 Dive02 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L4: Campaign to...

  17. EX1504L2 Dive03 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L2: Campaign to...

  18. TECHNOLOGY NEEDS AND STATUS ON CLOSURE OF DOE RADIOACTIVE WASTE TANK ANCILLARY SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    Burns, H; Sharon Marra, S; Christine Langton, C

    2009-01-21

    This paper summarizes the current state of art of sampling, characterizing, retrieving, transferring and treating the incidental waste and stabilizing the void space in tank ancillary systems and the needs involved with closure of these systems. The overall effort for closing tank and ancillary systems is very large and is in the initial stages of being addressed in a systematic manner. It was recognized in doing this effort, that gaps in both technology and material application for characterization and removal of residual waste and closure of ancillary systems would be identified. Great efficiencies are to be gained by defining the technology need areas early in the closure process and providing recommendations for technical programs to improve the closure strategies. Therefore, this paper will not only summarize the state of closure of ancillary systems but also provide recommendations to address the technology gaps identified in this assessment.

  19. Utilization of Ancillary Data Sets for SMAP Algorithm Development and Product Generation

    Science.gov (United States)

    ONeill, P.; Podest, E.; Njoku, E.

    2011-01-01

    Algorithms being developed for the Soil Moisture Active Passive (SMAP) mission require a variety of both static and ancillary data. The selection of the most appropriate source for each ancillary data parameter is driven by a number of considerations, including accuracy, latency, availability, and consistency across all SMAP products and with SMOS (Soil Moisture Ocean Salinity). It is anticipated that initial selection of all ancillary datasets, which are needed for ongoing algorithm development activities on the SMAP algorithm testbed at JPL, will be completed within the year. These datasets will be updated as new or improved sources become available, and all selections and changes will be documented for the benefit of the user community. Wise choices in ancillary data will help to enable SMAP to provide new global measurements of soil moisture and freeze/thaw state at the targeted accuracy necessary to tackle hydrologically-relevant societal issues.

  20. EX1504L2 Dive07 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L2: Campaign to...

  1. EX1504L2 Dive14 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L2: Campaign to...

  2. EX1504L4 Dive08 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L4: Campaign to...

  3. Technical and economic aspects of ancillary services markets in the electric power industry: an international comparison

    International Nuclear Information System (INIS)

    We present a comparative analysis of technical and economic aspects of ancillary services on the markets of England and Wales, Nordic Countries, California, Argentina, Australia and Spain, comparing the services of voltage control, frequency regulation and system restoration. All the analyzed markets rely on the existence of an administrator of ancillary services, function that leads to the figure of the system operator. Among the services analyzed, the mandatory nature of voltage control and primary frequency regulation stands out, being both the ancillary services with the higher market price and the shortest period of time requirements. In general, the recognized costs of the services correspond to investments operation, maintenance, and opportunity costs. In the provision of these ancillary services, there are no clear preferences for a particular resource allocation mechanism, where mandatory provision, auctions, competitive offers and different time length bilateral contracts are combined

  4. EX1504L2 Dive13 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L2: Campaign to...

  5. EX1504L2 Dive16 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L2: Campaign to...

  6. EX1504L3 Dive05 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L3: CAPSTONE Leg III:...

  7. EX1504L2 Dive01 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L2: Campaign to...

  8. EX1504L2 Dive12 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L2: Campaign to...

  9. EX1504L4 Dive10 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L4: Campaign to...

  10. EX1504L4 Dive13 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L4: Campaign to...

  11. EX1504L4 Dive09 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L4: Campaign to...

  12. EX1504L4 Dive11 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L4: Campaign to...

  13. EX1504L3 Dive07 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L3: CAPSTONE Leg III:...

  14. EX1504L3 Dive06 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L3: CAPSTONE Leg III:...

  15. EX1504L2 Dive10 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L2: Campaign to...

  16. EX1504L4 Dive06 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L4: Campaign to...

  17. EX1504L2 Dive15 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L2: Campaign to...

  18. EX1504L2 Dive09 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L2: Campaign to...

  19. EX1504L2 Dive06 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L2: Campaign to...

  20. EX1504L3 Dive02 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L3: CAPSTONE Leg III:...

  1. EX1504L3 Dive03 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L3: CAPSTONE Leg III:...

  2. EX1504L4 Dive03 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L4: Campaign to...

  3. EX1504L3 Dive04 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L3: CAPSTONE Leg III:...

  4. EX1504L4 Dive04 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L4: Campaign to...

  5. EX1504L4 Dive12 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L4: Campaign to...

  6. EX1504L2 Dive08 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L2: Campaign to...

  7. EX1504L4 Dive07 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L4: Campaign to...

  8. EX1504L2 Dive02 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L2: Campaign to...

  9. The Nordic approach to market-based provision of ancillary services

    International Nuclear Information System (INIS)

    This paper presents an overview of the markets for ancillary services, which are regulated and traded differently within and across borders in the Nordic countries. We describe the services provided and their characteristics in terms of definition, participation, contracting approach and duration, selection of offers, and dispatch criteria. Further, we assess the costs, specify the payments, and discuss cost allocation, and we conclude with a policy discussion of ancillary services in the Nordic countries

  10. The Nordic approach to market-based provision of ancillary services

    International Nuclear Information System (INIS)

    This paper presents an overview of the markets for ancillary services, which are regulated and traded differently within and across borders in the Nordic countries. We describe the services provided and their characteristics in terms of definition, participation, contracting approach and duration, selection of offers, and dispatch criteria. Further, we assess the costs, specify the payments, and discuss cost allocation, and we conclude with a policy discussion of ancillary services in the Nordic countries. (author)

  11. Manned maneuvering unit mission definition study. Volume 3: MMU ancillary support equipment and attachment concepts

    Science.gov (United States)

    1975-01-01

    An analysis of Manned Maneuvering Units (MMU) ancillary support equipment and attachment concepts is presented. The major objectives of the study are defined as: (1) identifying MMU applications which would supplement space shuttle safety and effectiveness, (2) to define general MMU performance and control requirements to satisfy candidate shuttle applications, (3) to develop concepts for attaching MMUs to various worksites and equipment, and (4) to identify requirements and develop concepts for MMU ancillary equipment.

  12. Ancillary benefits of climate policy in a small open economy: The case of Sweden

    International Nuclear Information System (INIS)

    It is increasingly recognised that GHG reduction policies can have important ancillary benefits in the form of positive local and regional environmental impacts. The purpose of this paper is to estimate the domestic ancillary pollution benefits of climate policy in Sweden, and investigate how these are affected by different climate policy designs. The latter differ primarily in terms of how the country chooses to meet a specific target and where the necessary emission reductions take place. The analysis relies on simulations within the energy system optimisation model TIMES-Sweden, and focuses on four non-GHG pollutants: Nitrogen Oxides (NOX), Non Methane Volatile Organic Compounds (NMVOC), inhalable particles (PM2.5), and Sulphur dioxide (SO2). The simulations permit detailed assessments of the respective technology and fuel choices that underlie any net changes in the estimated ancillary effects. The results indicate that the ancillary benefits constitute a far from insignificant share of total system costs, and this share appears to be highest in the scenarios that entail the largest emission reductions domestically. This result reflects the fact that carbon dioxide emission reductions abroad also implies a lost opportunity of achieving substantial domestic welfare gain from the reductions of regional and local environmental pollutants. - Highlights: → We estimate the domestic ancillary pollution benefits of climate policy in Sweden. → These constitute a sizeable share of total system costs. → The ancillary benefits are highest in the policy scenarios that entail the largest emission reductions domestically.

  13. Interaction of factor XIII subunits.

    Science.gov (United States)

    Katona, Eva; Pénzes, Krisztina; Csapó, Andrea; Fazakas, Ferenc; Udvardy, Miklós L; Bagoly, Zsuzsa; Orosz, Zsuzsanna Z; Muszbek, László

    2014-03-13

    Coagulation factor XIII (FXIII) is a heterotetramer consisting of 2 catalytic A subunits (FXIII-A2) and 2 protective/inhibitory B subunits (FXIII-B2). FXIII-B, a mosaic protein consisting of 10 sushi domains, significantly prolongs the lifespan of catalytic subunits in the circulation and prevents their slow progressive activation in plasmatic conditions. In this study, the biochemistry of the interaction between the 2 FXIII subunits was investigated. Using a surface plasmon resonance technique and an enzyme-linked immunosorbent assay-type binding assay, the equilibrium dissociation constant (Kd) for the interaction was established in the range of 10(-10) M. Based on the measured Kd, it was calculated that in plasma approximately 1% of FXIII-A2 should be in free form. This value was confirmed experimentally by measuring FXIII-A2 in plasma samples immunodepleted of FXIII-A2B2. Free plasma FXIII-A2 is functionally active, and when activated by thrombin and Ca(2+), it can cross-link fibrin. In cerebrospinal fluid and tears with much lower FXIII subunit concentrations, >80% of FXIII-A2 existed in free form. A monoclonal anti-FXIII-B antibody that prevented the interaction between the 2 subunits reacted with the recombinant combined first and second sushi domains of FXIII-B, and its epitope was localized to the peptide spanning positions 96 to 103 in the second sushi domain. PMID:24408323

  14. Security-constrained ancillary services allocation and pricing in integrated markets

    International Nuclear Information System (INIS)

    Ancillary services are used to control system frequency and to ensure the secure and reliable transmission of electricity from suppliers to consumers. A new dispatch formulation for determining optimal network security constraints for generator active-power schedules and the allocation of ancillary services was presented in this study. The conventional optimal power flow (OPF) formulation was based on an integrated market model with energy and ancillary services procured simultaneously using a co-optimization process. The Newton method for optimizing the Lagrange function formed from individual cost functions and constraints was used. The contingency formulation considered power demand variations at load nodes. Additional control variables were added in order to meet new load demands in the dispatch formulation. A Lagrange function was used to develop an extended set of security constraints as well as individual prices for ancillary service providers. Costs related to maintenance, lower efficiency and lower active-power generation were the variable costs of frequency control. Services compensating the transmission system losses between consumers and suppliers were described as grid loss compensation services. Case studies of representative power systems were used to verify the new dispatch calculation method. The study showed that minimizing the procurement costs of ancillary services can lead to insecure system operations. 13 refs., 3 tabs., 3 figs.

  15. Dimerization of the type IV pilin from Pseudomonas aeruginosa strain K122-4 results in increased helix stability as measured by time-resolved hydrogen-deuterium exchange

    Directory of Open Access Journals (Sweden)

    Cristina Lento

    2016-01-01

    Full Text Available Truncated pilin monomers from Pseudomonas aeruginosa strain K122-4 (ΔK122 have been shown to enter a monomer-dimer equilibrium in solution prior to oligomerization into protein nanotubes. Here, we examine the structural changes occurring between the monomeric and dimeric states of ΔK122 using time-resolved hydrogen-deuterium exchange mass spectrometry. Based on levels of deuterium uptake, the N-terminal α-helix and the loop connecting the second and third strands of the anti-parallel β-sheet contribute significantly to pilin dimerization. Conversely, the antiparallel β-sheet and αβ loop region exhibit increased flexibility, while the receptor binding domain retains a rigid conformation in the equilibrium state.

  16. Dimerization of the type IV pilin from Pseudomonas aeruginosa strain K122-4 results in increased helix stability as measured by time-resolved hydrogen-deuterium exchange.

    Science.gov (United States)

    Lento, Cristina; Wilson, Derek J; Audette, Gerald F

    2016-01-01

    Truncated pilin monomers from Pseudomonas aeruginosa strain K122-4 (ΔK122) have been shown to enter a monomer-dimer equilibrium in solution prior to oligomerization into protein nanotubes. Here, we examine the structural changes occurring between the monomeric and dimeric states of ΔK122 using time-resolved hydrogen-deuterium exchange mass spectrometry. Based on levels of deuterium uptake, the N-terminal α-helix and the loop connecting the second and third strands of the anti-parallel β-sheet contribute significantly to pilin dimerization. Conversely, the antiparallel β-sheet and αβ loop region exhibit increased flexibility, while the receptor binding domain retains a rigid conformation in the equilibrium state. PMID:26798830

  17. Ancillary Services for the European Grid with High Shares of Wind and Solar Power

    DEFF Research Database (Denmark)

    Van Hulle, Frans; Holttinen, Hannele; Kiviluoma, Juha;

    2012-01-01

    With significantly increasing share of variable renewable power generation like wind and solar PV, the need in the power system for ancillary services supporting the network frequency, voltage, etc. changes. Turning this issue around, market opportunities will emerge for wind and solar PV...... technology to deliver such grid services. In the European power system, adequate market mechanisms need to be developed to ensure that there will be an efficient trading of these services. For that purpose a range of (economic) characteristics of wind (and solar) power as providers of grid services need......) conceptually analyzing system needs for ancillary services and at assessing the technical aspects of and cost of delivering these services by solar PV and wind power, in scenarios of high renewable penetration. (2) Investigation of the need for ancillary services in typical transmission and distribution...

  18. Ancillary services in the health care industry: is Six Sigma reasonable?

    Science.gov (United States)

    Johnstone, Peter A S; Hendrickson, Julie A W; Dernbach, Allison J; Secord, Ann R; Parker, John C; Favata, Michael A; Puckett, Michael L

    2003-01-01

    Within the naval medical center construct, the disparate disciplines encompassed within ancillary services lend themselves to formal quality analysis and process improvement. This analysis uses the Six Sigma approach. Error rates were investigated and calculated for various processes within ancillary services at Naval Medical Center, San Diego. These were translated into the common metric of defects per million opportunities (DPMO). DPMO rates vary between 21.5 and 420,000. These correspond to Sigma values from 1.7 to approaching 6. Rates vary with biological complexity of the system and the degree of automation available. Some ancillary services translate well into a Six Sigma schema. Systems with high potential patient risk if performed poorly and those amenable to second checking and computer oversight may be candidates for such optimization. This should be undertaken in a local environment conducive to individual error reporting, and in a corporate environment with the will and funding to support the transition. PMID:12593375

  19. Nomenclature for Ion channel Subunits

    OpenAIRE

    Bradley, Jonathan; Frings, Stephan; Yau, King-Wai; Reed, Randall

    2001-01-01

    Presents the nomenclature for ion channel subunits. Role of ion channels in the mediation of visual and olfactory signal transduction; Expression of ion channels in cell types and tissues; Assessment on the nucleotide sensitivity, ion conductance and calcium modulation in heteromers.

  20. Loads Providing Ancillary Services: Review of InternationalExperience-- Technical Appendix: Market Descriptions

    Energy Technology Data Exchange (ETDEWEB)

    Grayson Heffner, Charles Goldman, Kintner-Meyer, M; Kirby, Brendan

    2007-05-01

    In this study, we examine the arrangements for andexperiences of end-use loads providing ancillary services (AS) in fiveelectricity markets: Australia, the United Kingdom (UK), the Nordicmarket, and the ERCOT and PJM markets in the United States. Our objectivein undertaking this review of international experience was to identifyspecific approaches or market designs that have enabled customer loads toeffectively deliver various ancillary services (AS) products. We hopethat this report will contribute to the ongoing discussion in the U.S.and elsewhere regarding what institutional and technical developments areneeded to ensure that customer loads can meaningfully participate in allwholesale electricity markets.

  1. Benthic macrofauna and ancillary data for San Francisco Bay, California, March to November 1987

    Science.gov (United States)

    Schemel, Laurence E.; Ota, Allan Y.; Harmon, J.G.; Shay, J.M.; Adorado, R.N.

    1988-01-01

    Benthic macrofauna and ancillary data were collected during 1987 as part of the U.S. Geological Survey Regional Effects Monitoring Program in San Francisco Bay, California. Data were collected during five cruises at 2-month intervals from March through November. Benthic macrofauna for identification of species and sediment for size analysis were sampled at eight stations. Ancillary data, which consisted of salinity, temperature, dissolved-oxygen concentrations, and suspended sediment, were collected at 12 stations. Salinity and temperature were measured at three stations that coincided with continuous water quality monitors. Abundances and geographical distributions of a newly introduced species of clam were measured. (USGS)

  2. Characterization of fimbrial subunits from Bordetella species

    NARCIS (Netherlands)

    Mooi, F.R.; Heide, H.G.J. van der; Avest, A.R. ter; Welinder, K.G.; Livey, I.; Zeijst, B.A.M. van der; Gaastra, W.

    1987-01-01

    Using antisera raised against serotype 2 and 3 fimbrial subunits from Bordetella pertussis, serologically related polypeptides were detected in Bordetella bronchiseptica, Bordetella parapertussis and Bordetella avium strains. The two B. pertussis fimbrial subunits, and three of the serologically rel

  3. The beta subunit of casein kinase II

    DEFF Research Database (Denmark)

    Boldyreff, B; Piontek, K; Schmidt-Spaniol, I; Issinger, O G

    1991-01-01

    cDNAs encoding the beta subunit of pig and mouse CKII were isolated. The porcine cDNA was expressed as a fusion protein in Escherichia coli and used for the production of anti-CKII-beta subunit specific antibodies.......cDNAs encoding the beta subunit of pig and mouse CKII were isolated. The porcine cDNA was expressed as a fusion protein in Escherichia coli and used for the production of anti-CKII-beta subunit specific antibodies....

  4. Regulatory issues associated with closure of the Hanford AX Tank Farm ancillary equipment

    International Nuclear Information System (INIS)

    Liquid mixed, high-level radioactive waste has been stored in underground single-shell tanks at the US Department of Energy's (DOE's) Hanford Site. After retrieval of the waste from the single-shell tanks, the DOE will proceed with closure of the tank farm. The 241-AX Tank Farm includes four one-million gallon single-shell tanks in addition to sluice lines, transfer lines, ventilation headers, risers, pits, cribs, catch tanks, buildings, well and associated buried piping. This equipment is classified as ancillary equipment. This document addresses the requirements for regulatory close of the ancillary equipment in the Hanford Site 241-AX Tank Farm. The options identified for physical closure of the ancillary equipment include disposal in place, disposal in place after treatment, excavation and disposal on site in an empty single-shell tank, and excavation and disposal outside the AX Tank Farm. The document addresses the background of the Hanford Site and ancillary equipment in the AX Tank Farm, regulations for decontamination and decommissioning of radioactively contaminated equipment, requirements for the cleanup and disposal of radioactive wastes, cleanup and disposal requirements governing hazardous and mixed waste, and regulatory requirements and issues associated with each of the four physical closure options. This investigation was conducted by the Sandia National Laboratories, Albuquerque, New Mexico, during Fiscal Year 1998 for the Hanford Tanks Initiative Project

  5. Regulatory issues associated with closure of the Hanford AX Tank Farm ancillary equipment

    Energy Technology Data Exchange (ETDEWEB)

    Becker, D.L.

    1998-09-02

    Liquid mixed, high-level radioactive waste has been stored in underground single-shell tanks at the US Department of Energy`s (DOE`s) Hanford Site. After retrieval of the waste from the single-shell tanks, the DOE will proceed with closure of the tank farm. The 241-AX Tank Farm includes four one-million gallon single-shell tanks in addition to sluice lines, transfer lines, ventilation headers, risers, pits, cribs, catch tanks, buildings, well and associated buried piping. This equipment is classified as ancillary equipment. This document addresses the requirements for regulatory close of the ancillary equipment in the Hanford Site 241-AX Tank Farm. The options identified for physical closure of the ancillary equipment include disposal in place, disposal in place after treatment, excavation and disposal on site in an empty single-shell tank, and excavation and disposal outside the AX Tank Farm. The document addresses the background of the Hanford Site and ancillary equipment in the AX Tank Farm, regulations for decontamination and decommissioning of radioactively contaminated equipment, requirements for the cleanup and disposal of radioactive wastes, cleanup and disposal requirements governing hazardous and mixed waste, and regulatory requirements and issues associated with each of the four physical closure options. This investigation was conducted by the Sandia National Laboratories, Albuquerque, New Mexico, during Fiscal Year 1998 for the Hanford Tanks Initiative Project.

  6. Improving the Quality of Ability Estimates through Multidimensional Scoring and Incorporation of Ancillary Variables

    Science.gov (United States)

    de la Torre, Jimmy

    2009-01-01

    For one reason or another, various sources of information, namely, ancillary variables and correlational structure of the latent abilities, which are usually available in most testing situations, are ignored in ability estimation. A general model that incorporates these sources of information is proposed in this article. The model has a general…

  7. Risk Management: Supporting the District's Ancillary Services Staff

    Science.gov (United States)

    Waldmann, Steve; Strasburger, Tom

    2013-01-01

    The everyday operations of a school district depend on a network of people, including students, teachers, staff, and administrators. However, the ancillary services staff are really responsible for making the school day run smoothly. They are often the first employees that students see in the morning, either on the school bus or in the cafeteria,…

  8. Optimal Sizing and Allocation of Residential Photovoltaic Panels in a Distribution Network for Ancillary Services Application

    DEFF Research Database (Denmark)

    Kordheili, Reza Ahmadi; Pourmousavi, Ali; Pillai, Jayakrishnan Radhakrishna; M. Hasanien, Hany; Bak-Jensen, Birgitte; Nehrir, M. Hashem

    Tremendous penetration of renewable energy in electric networks, despite its valuable opportunities, such as balancing reserve and ancillary service, has raised concerns for network operators. Such concern stems from grid operating conditions. Such huge penetration can lead to violation in the gr...

  9. Ancillary Frequency Control of Direct Drive Full-Scale Converter Based Wind Power Plants

    DEFF Research Database (Denmark)

    Hu, Weihao; Su, Chi; Fang, Jiakun; Chen, Zhe; Hu, Yanting

    2013-01-01

    This paper presents a simulation model of a wind power plant based on a MW-level variable speed wind turbine with a full-scale back-to-back power converter developed in the simulation tool of DIgSILENT Power Factory. Three different kinds of ancillary frequency control strategies, namely inertia...

  10. Ancillary services: technical specifications, system needs and costs. Deliverable D 2.2

    DEFF Research Database (Denmark)

    Holttinen, Hannele; Cutululis, Nicolaos Antonio; Gubina, Andrej;

    2012-01-01

    In this report, different ancillary services are described and a table listing main services is presented. While Chapter 2 is describing the services from (renewable) generators point of view, Chapter 3 is considering future system needs for services with increased wind and solar penetration. The...

  11. Mixed integer non-linear programming and Artificial Neural Network based approach to ancillary services dispatch in competitive electricity markets

    International Nuclear Information System (INIS)

    Highlights: • Ancillary services market management. • Ancillary services requirements forecast based on Artificial Neural Network. • Ancillary services clearing mechanisms without complex bids and with complex bids. - Abstract: Ancillary services represent a good business opportunity that must be considered by market players. This paper presents a new methodology for ancillary services market dispatch. The method considers the bids submitted to the market and includes a market clearing mechanism based on deterministic optimization. An Artificial Neural Network is used for day-ahead prediction of Regulation Down, regulation-up, Spin Reserve and Non-Spin Reserve requirements. Two test cases based on California Independent System Operator data concerning dispatch of Regulation Down, Regulation Up, Spin Reserve and Non-Spin Reserve services are included in this paper to illustrate the application of the proposed method: (1) dispatch considering simple bids; (2) dispatch considering complex bids

  12. Ancillary human health benefits of improved air quality resulting from climate change mitigation

    Directory of Open Access Journals (Sweden)

    Krupnick Alan J

    2008-07-01

    Full Text Available Abstract Background Greenhouse gas (GHG mitigation policies can provide ancillary benefits in terms of short-term improvements in air quality and associated health benefits. Several studies have analyzed the ancillary impacts of GHG policies for a variety of locations, pollutants, and policies. In this paper we review the existing evidence on ancillary health benefits relating to air pollution from various GHG strategies and provide a framework for such analysis. Methods We evaluate techniques used in different stages of such research for estimation of: (1 changes in air pollutant concentrations; (2 avoided adverse health endpoints; and (3 economic valuation of health consequences. The limitations and merits of various methods are examined. Finally, we conclude with recommendations for ancillary benefits analysis and related research gaps in the relevant disciplines. Results We found that to date most assessments have focused their analysis more heavily on one aspect of the framework (e.g., economic analysis. While a wide range of methods was applied to various policies and regions, results from multiple studies provide strong evidence that the short-term public health and economic benefits of ancillary benefits related to GHG mitigation strategies are substantial. Further, results of these analyses are likely to be underestimates because there are a number of important unquantified health and economic endpoints. Conclusion Remaining challenges include integrating the understanding of the relative toxicity of particulate matter by components or sources, developing better estimates of public health and environmental impacts on selected sub-populations, and devising new methods for evaluating heretofore unquantified and non-monetized benefits.

  13. Market and policy barriers for demand response providing ancillary services in U.S. markets

    Energy Technology Data Exchange (ETDEWEB)

    Cappers, Peter [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); MacDonald, Jason [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Goldman, Charles [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)

    2013-03-01

    This study provides an examination of various market and policy barriers to demand response providing ancillary services in both ISO/RTO and non-ISO/RTO regions, especially at the program provider level. It is useful to classify barriers in order to create a holistic understanding and identify parties that could be responsible for their removal. This study develops a typology of barriers focusing on smaller customers that must rely on a program provider (i.e., electric investor owned utility or IOU, ARC) to create an aggregated DR resource in order to bring ancillary services to the balancing authority. The barriers were identified through examinations of regulatory structures, market environments, and product offerings; and discussions with industry stakeholders and regulators. In order to help illustrate the differences in barriers among various wholesale market designs and their constituent retail environments, four regions were chosen to use as case studies: Colorado, Texas, Wisconsin, and New Jersey.

  14. VOLTTRON-Based System for Providing Ancillary Services with Residential Building Loads

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Xin

    2016-07-01

    Ancillary services entail controlled modulation of building equipment to maintain a stable balance of generation and load in the power system. Ancillary services include frequency regulation and contingency reserves, whose acting time ranges from several seconds to several minutes. Many pilot studies have been implemented to use industrial loads to provide ancillary services, and some have explored services from commercial building loads or electric vehicle charging loads. Residential loads, such as space conditioning and water heating, represent a largely untapped resource for providing ancillary services. The residential building sector accounts for a significant fraction of the total electricity use in the United States. Many loads in residential buildings are flexible and could potentially be curtailed or shifted at the request of the grid. However, there are many barriers that prevent residential loads being widely used for ancillary services. One of the major technical barriers is the lack of communication capabilities between end-use devices and the grid. End-use devices need to be able to receive the automatic generation control (AGC) signal from the grid operator and supply certain types of telemetry to verify response. With the advance of consumer electronics, communication-enabled, or 'connected,' residential equipment has emerged to overcome the communication barrier. However, these end-use devices have introduced a new interoperability challenge due to the existence of numerous standards and communication protocols among different end devices. In this paper, we present a VOLTTRON-based system that overcomes these technical challenges and provides ancillary services with residential loads. VOLTTRON is an open-source control and sensing platform for building energy management, facilitating interoperability solutions for end devices. We have developed drivers to communicate and control different types of end devices through standard

  15. Simulated annealing to handle energy and ancillary services joint management considering electric vehicles

    DEFF Research Database (Denmark)

    Sousa, Tiago M; Soares, Tiago; Morais, Hugo;

    2016-01-01

    The massive use of distributed generation and electric vehicles will lead to a more complex management of the power system, requiring new approaches to be used in the optimal resource scheduling field. Electric vehicles with vehicle-to-grid capability can be useful for the aggregator players in the...... mitigation of renewable sources intermittency and in the ancillary services procurement. In this paper, an energy and ancillary services joint management model is proposed. A simulated annealing approach is used to solve the joint management for the following day, considering the minimization of the...... aggregator total operation costs. The case study considers a distribution network with 33-bus, 66 distributed generation and 2000 electric vehicles. The proposed simulated annealing is matched with a deterministic approach allowing an effective and efficient comparison. The simulated annealing presents a...

  16. Simulating the Operation of Markets for Bulk-Power Ancillary Services

    OpenAIRE

    Eric Hirst; Brendan Kirby

    1998-01-01

    The U.S. Federal Energy Regulatory Commission (FERC) requires electric utilities to offer six ancillary services. Most of the tariffs filed with FERC price these services on the basis of traditional cost-of-service (embedded) costs, Because most of these services are provided by generating units, however, it should be possible to create competitive markets for them. This paper describes, the structure of, and results from, a spreadsheet model that simulates markets for seven services: losses,...

  17. Techno-economic analysis of energy storage systems for grid ancillary services

    OpenAIRE

    Peracaula Ruiz, Àlex

    2014-01-01

    In a future with a higher renewable penetration, energy storage technologies will play an important role. They may, for example, use curtailed energy for arbitrage or supply ancillary services, help in relieving the grid congestion, and promote distributed generation. A techno-economic understanding and comparison between several electrical energy storage options is pursued as the main objective. Technologies with particular interest are: pumped hydropower storage, compressed air energy stora...

  18. Improved Sea Surface Salinity Retrievals using Ancillary data for Aquarius Ocean Roughness Correction

    Science.gov (United States)

    Jones, L.; Hejazin, Y.; Rabollii, M.

    2012-12-01

    The Aquarius/SAC-D sea surface salinity (SSS) measurement mission was launched into polar orbit during the summer of 2011. The prime sensor is a combined L-band radiometer/scatterometer developed jointly by NASA Goddard Space Flight Center and the Jet Propulsion Laboratory, which derives SSS from ocean surface brightness temperature (Tb) measurements. This paper deals with a method of improving AQ SSS by making a making an ocean roughness brightness temperature correction (ΔTbr). The ΔTbr is derived using several ancillary data sources of surface wind measurements, namely; NOAA numerical weather model - Global Data Assimilation System (GDAS), WindSat ocean vector wind, and the CONAE Microwave Radiometer (MWR). The basis of the correction is the excess (warming) brightness temperature that is produced when the ocean is roughened by the surface wind. We model the increase in L-band Tb as a function of wind speed and direction relative to the antenna azimuth look direction. Our radiative transfer model by El-Nimri [2010] has been tuned to actual AQ ocean surface Tb's with corresponding surface wind vector. Using this ocean emissivity model and the ancillary wind vector, we derive the roughness correction, ΔTbr, which is applied to the AQ measured ocean surface Tb before retrieving SSS. Finally the effect of ΔTbr is evaluated by computing the difference between the HYCOM ocean salinity model and the AQ retrievals. These differences are cross correlated with the ancillary surface wind vector to assess the effectiveness of the roughness correction. Finally, we compare our ΔTbr with the AQ scatterometer derived ΔTbr. We compare the similarities and differenced versus the ancillary surface wind speed. S. El-Nimri et al., 2010, "An improved C-band ocean surface emissivity model at hurricane force wind speeds over a wide range of earth incidence angles," IEEE Geosci. Rem. Sens. Letters, vol. 7, NO. 4, October.

  19. Nuclear structure at high spin using multidetector gamma array and ancillary detectors

    Indian Academy of Sciences (India)

    S Muralithar

    2014-04-01

    A multidetector gamma array (GDA), for studying nuclear structure was built with ancillary devices namely gamma multiplicity filter and charged particle detector array. This facility was designed for in-beam gamma spectroscopy measurements in fusion evaporation reactions at Inter-University Accelerator Centre, New Delhi. Description of the facility and in-beam performance with two experimental studies done are presented. This array was used in a number of nuclear spectroscopic and reaction investigations.

  20. Usage of direct search methods in predictive control of ancillary services

    International Nuclear Information System (INIS)

    Most European transmission systems are interconnected to ensure the reliability and accessibility of electric power supply. Transmission system operators (TSOs) are responsible for ensuring that contracted cross-border supplies are available and that deficits are accommodated. TSOs typically buy ancillary services in advance for use in periods of deficit. This paper described a predictive control approach for ancillary services in interconnected electricity systems. The model was designed to predict the difference between contracted and actual cross-border transmission of electric power. The power sources were considered as individual power plants. The receding horizon principle was applied in order to compute the time sequences of individual sources for longer prediction periods using only the initial part of the sequences. Coverage included positive tertiary regulation; negative tertiary regulation; quickstart; dispatch reserve; and energy bought from other countries. Inputs were converted into binary values for the optimization algorithm. The technical properties of individual sources were used as fundamental constraints. The optimization algorithm was able to determine optimal sequences of ancillary services within a prediction horizon of 6 hours. 6 refs., 1 tab., 6 figs.

  1. Analysis of the Impact of Wind Power Participating in Both Energy and Ancillary Services Markets – The Danish Case

    DEFF Research Database (Denmark)

    Soares, Tiago; Morais, Hugo; Pinson, Pierre

    2014-01-01

    The impact of a high penetration of wind power generation in power systems motivates need for an assessment of its inte raction with electricity markets. With the continuous evolution of wind turbines technology, wind farms have today the ability to provide certain ancillary services with...... appropriate levels of security and reliability . The participation of wind f arms i n ancillary service market s ought to rely on market designs and offering strategies that satisfy power system needs, as well as their operating characteristics . Here we evaluate the system impact of different offering...... strategies that wind farms employ on ene rgy and ancillary service market. A lready proposed Proportional Wind Reserve Strategy (PWRS) and a Continuo us Wind Reserve Strategy (CWRS) are used to determine the amount of available power for ancillary services. A case study based on real and recent dat a for...

  2. 76 FR 36400 - Third-Party Provision of Ancillary Services; Accounting and Financial Reporting for New Electric...

    Science.gov (United States)

    2011-06-22

    ... providing ancillary services; and accounting and financial reporting matters as they relate to recovery of costs for electric storage technologies, noting that the Commission's accounting and financial reporting... Requirements for Energy Storage Resources 23. The Commission's accounting \\40\\ and financial...

  3. Ancillary services for the European grid with high shares of wind and solar power

    Energy Technology Data Exchange (ETDEWEB)

    Hulle, Frans van [EWEA, Brussels (Belgium); Holttinen, Hannele; Kiviluoma, Juha [VTT (Finland); Cutululis, Nicolaos [DTU (Denmark)

    2012-07-01

    With significantly increasing share of variable renewable power generation like wind and solar PV, the need in the power system for ancillary services supporting the network frequency, voltage, etc. changes. Turning this issue around, market opportunities will emerge for wind and solar PV technology to deliver such grid services. In the European power system, adequate market mechanisms need to be developed to ensure that there will be an efficient trading of these services. For that purpose a range of (economic) characteristics of wind (and solar) power as providers of grid services need to be better understood. This relates both to the technical capabilities of the plants for delivering specific services and to the quantification of the needs. The paper presents the approach of the European lEE project REserviceS, aiming at establishing reference guidance for the ongoing developments in Europe of network codes and electricity market design. Economic insights gained from REserviceS will be shaped into recommendations to be used when establishing electricity market mechanisms and Network Codes at EU level. The project approach presented in the paper consists of two main parts namely (1) conceptually analyzing system needs for ancillary services and at assessing the technical aspects of and cost of delivering these services by solar PV and wind power, in scenarios of high renewable penetration. (2) Investigation of the need for ancillary services in typical transmission and distribution networks, and the cost and options to deliver these services at high penetration. The paper will give an overview of case studies envisaged, together with the intended methods used for the analysis. The paper also gives some initial project results. It presents the outcome of the assessment of ancillary services that are especially relevant for wind and solar power. These are mainly related to frequency, voltage control and restoration of the system. In addition, based on existing

  4. CO{sub 2} mitigation costs and ancillary benefits in the Nordic countries, the UK and Ireland: A survey

    Energy Technology Data Exchange (ETDEWEB)

    Kverndokk, Snorre; Rosendahl, Knut Einar

    2000-07-01

    This paper provides a survey of top-down modelling studies on mitigation costs and ancillary benefits in the Nordic countries, the UK and Ireland. Special emphasis is put on results concerning revenue recycling, double dividend, distributional effects and ancillary benefits. According to the papers surveyed, modest emissions restrictions as those given by the Kyoto Protocol, can be met without substantial costs for the countries studied. (Author)

  5. Ancillary Benefits for Caregivers of Children with Asthma Participating in an Environmental Intervention Study to Alleviate Asthma Symptoms

    OpenAIRE

    Clougherty, Jane E; Kubzansky, Laura D; Spengler, John D.; Levy, Jonathan I.

    2009-01-01

    Providing care for children with asthma can be demanding and time-intensive with far-reaching effects on caregivers’ lives. Studies have documented childhood asthma symptom reductions and improved asthma-related quality of life (AQOL) with indoor allergen-reducing environmental interventions. Few such studies, however, have considered ancillary benefits to caregivers or other family members. Ancillary benefits could be derived from child health improvements and reduced caregiving burden or fr...

  6. Production and delivery of recombinant subunit vaccines

    OpenAIRE

    Andersson, Christin

    2000-01-01

    Recombinant strategies are today dominating in thedevelopment of modern subunit vaccines. This thesis describesstrategies for the production and recovery of protein subunitimmunogens, and how genetic design of the expression vectorscan be used to adapt the immunogens for incorporation intoadjuvant systems. In addition, different strategies fordelivery of subunit vaccines by RNA or DNA immunization havebeen investigated. Attempts to create general production strategies forrecombinant protein i...

  7. Integrating TM and Ancillary Geographical Data with Classification Trees for Land Cover Classification of Marsh Area

    Institute of Scientific and Technical Information of China (English)

    NA Xiaodong; ZHANG Shuqing; ZHANG Huaiqing; LI Xiaofeng; YU Huan; LIU Chunyue

    2009-01-01

    The main objective of this research is to determine the capacity of land cover classification combining spectral and textural features of Landsat TM imagery with ancillary geographical data in wetlands of the Sanjiang Plain, Heilongjiang Province, China. Semi-variograms and Z-test value were calculated to assess the separability of grey-level co-occurrence texture measures to maximize the difference between land cover types. The degree of spatial autocorrelation showed that window sizes of 3×3 pixels and 11×11 pixels were most appropriate for Landsat TM image texture calculations. The texture analysis showed that co-occurrence entropy, dissimilarity, and variance texture measures, derived from the Landsat TM spectrum bands and vegetation indices provided the most significant statistical differentiation between land cover types. Subsequently, a Classification and Regression Tree (CART) algorithm was applied to three different combinations of predictors: 1) TM imagery alone (TM-only); 2) TM imagery plus image texture (TM+TXT model); and 3) all predictors including TM imagery, image texture and additional ancillary GIS information (TM+TXT+GIS model). Compared with traditional Maximum Likelihood Classification (MLC) supervised classification, three classification trees predictive models reduced the overall error rate significantly. Image texture measures and ancillary geographical variables depressed the speckle noise effectively and reduced classification error rate of marsh obviously. For classification trees model making use of all available predictors, omission error rate was 12.90% and commission error rate was 10.99% for marsh. The developed method is portable, relatively easy to implement and should be applicable in other settings and over larger extents.

  8. Inhaled hyaluronic acid as ancillary treatment in children with bacterial acute rhinopharyngitis.

    Science.gov (United States)

    Varricchio, A; Capasso, M; Avvisati, F; Varricchio, A M; De Lucia, A; Brunese, F P; Ciprandi, G

    2014-01-01

    Acute rhinopharyngitis (ARP) is the most common upper respiratory infection in children and represents a social problem for both the pharmaco-economic impact and a burden for the family. Topical antibiotic therapy is usually effective in bacterial ARP, but ancillary treatment might improve its efficacy. Hyaluronic acid (HA) is a promising molecule that has been recently proposed in upper respiratory disorders. Therefore, the purpose of this study was to evaluate the effects of ancillary HA treatment in children with bacterial ARP. Globally, 51 children (27 males, mean age 5.9 ± 2.1 years) with bacterial ARP were enrolled in the study. At baseline, children were randomly assigned to the treatment with: 125 mg of thiamphenicol diluted in 4 mL of saline isotonic solution twice daily (group A) or with 125 mg of thiamphenicol plus 4 ml of sodium hyaluronate 0.2% plus xylitol 5% (Aluneb, Sakura Italia) twice daily (group B) administered by the nasal device Rinowash (Airliquide Medical System, Italy) and connected to an aerosol nebulizer with pneumatic compressor (1.5 bar per 5 L/min) Nebula (Airliquide Medical System, Italy), for 10 days. sVAS, nasopharyngeal spotting, neutrophils and bacteria were assessed at baseline and after the treatment. Both treatments induced significant reduction of symptom perception, spotting, neutrophil and bacteria count. However, thiamphenicol plus HA was able to significantly induce a greater effect on sVAS (p=0.006), neutrophil count (p=0.01), and bacteria count (p=0.0003) than thiamphenicol alone. In conclusion, this study provides the first evidence that intranasal HA, as ancillary treatment, may be able to improve topical antibiotic efficacy in children with bacterial ARP. PMID:25316142

  9. Resource and revenue potential of California residential load participation in ancillary services

    International Nuclear Information System (INIS)

    Increasing penetrations of intermittent renewable energy resources will require additional power system services. California recently adopted an energy storage mandate to support its renewable portfolio standard, which requires 33% of delivered energy from renewables by 2020. The objective of this paper is to estimate the amount of energy storage that could be provided by residential thermostatically controlled loads, such as refrigerators and air conditioners, and the amount of revenue that could be earned by loads participating in ancillary services markets. We model load aggregations as virtual energy storage, and use simple dynamical system models and publicly available data to generate our resource and revenue estimates. We find that the resource potential is large: 10–40 GW/8–12 GWh, which is significantly more than that required by the mandate. We also find that regulation and spinning/non-spinning reserve revenues vary significantly depending upon type of load and, for heat pumps and air conditioners, climate zone. For example, mean regulation revenues for refrigerators are $11/year, for electric water heaters are $24/year, for air conditioners are $0-32/year, and for heat pumps are $22–56/year. Both consumer choices, such as appliance settings, and policy, such as the design of ancillary service compensation and appliance standards, could increase revenue potentials. - Highlights: • California's energy storage mandate requires 1.325 GW of energy storage by 2020. • Residential loads such as refrigerators have thermal energy storage. • California's residential loads could provide 10-40 GW/8-12 GWh of storage. • Loads participating in ancillary services markets could earn up to $56/load/year. • Consumer choices and policy mechanisms could increase revenue potentials

  10. Identifying children in need of ancillary and enabling services: a population approach.

    Science.gov (United States)

    Benedict, Ruth E; Farel, Anita M

    2003-12-01

    Children with chronic or disabling conditions use health, education and social services at a higher rate than their healthy peers. Estimates of the number of children in need of these specialized services are widely varied and often depend on categorical definitions that do not account for either the diversity or commonality of their experiences. Developing methods for identifying the population in need of services, particularly children likely to use long-term ancillary (audiology, occupational, physical or speech therapy, or social work) and/or enabling services (special equipment, personal care assistance, respite care, transportation, or environmental modifications), is essential for effective policy and program implementation. This study examines several recent attempts to operationalize definitions of children with chronic conditions using a noncategorical classification approach. Particular emphasis is placed on the subgroup of children identified as having functional limitations. Proposed operational definitions of children with functional limitations are compared using data from the 1994-1995 Disability Supplement to the US National Health Interview Survey. Estimates of the number of children reported to be using ancillary and enabling services are generated and compared across operational definitions of functional limitation as well as by the number, severity, and type (i.e. mobility, self-care, communication/sensory, social cognition/learning ability) of limitation. Depending on the operational definition selected, 9-14% of US community-dwelling children are estimated to have functional limitations. Among children with limitations, 26-30% regularly use ancillary services and 11-14% use enabling services. The strengths, limitations, and potential applications for each operational definition are discussed. PMID:14512235

  11. Technical Feasibility of Ancillary Services provided by ReGen Plants

    OpenAIRE

    Altin, Müfit; Han, Xue; Hansen, Anca Daniela; Løvenstein Olsen, Rasmus; Nicolaos Antonio CUTULULIS; Iov, Florin

    2015-01-01

    This report is the first deliverable in WP1 in the project “Ancillary services from renewable power plants” (RePlan). RePlan is funded as PSO project 2015 no. 12347 by the Danish PSO-programme ForskEL, which is administered by Energinet.DK. RePlan is carried out in collaboration between DTU Wind Energy, DTU Elektro, Aalborg University Energy Technology, Aalborg University Wireless Communication Networks and Vestas Wind System A/S. DTU Wind Energy is manager of the project.

  12. Ancillary Benefits and Net Costs of Climate Policies; FINAL Project Report

    International Nuclear Information System (INIS)

    A number of actions to slow atmospheric accumulation of greenhouse gases (GHGs) from fossil fuel use also could reduce conventional air pollutants in the U.S. The benefits that result would be ''ancillary'' to greenhouse gas abatement. Moreover, the benefits would tend to accrue locally and in the near term, while benefits from reduced climate change mostly accrue globally and over a time frame of several decades or longer. A failure to adequately consider ancillary benefits could lead to an incorrect assessment of the ''net costs'' of mitigation policies--that is, the direct cost of climate policy less ancillary benefits that result from those policies--and an incorrect identification of ''no regrets'' levels of GHG mitigation. It also could lead to the choice of a policy that was unnecessarily expensive because of its failure to exploit fully potential ancillary benefits. The focus of this project was on reductions in carbon dioxide that would be achieved in the electricity sector. A detailed model of the electricity sector was extended and used to simulate a variety of policies aimed at reducing GHGs. The output from this model was evaluated using an integrated assessment model to account for atmospheric transport model for secondary particulates stemming from nitrogen oxides (NOx) and sulfur dioxide (SO2) emissions. The resulting changes in atmospheric concentrations of particulates were fed into a health epidemiology model to estimate changes in health status, and these changes were valued in monetary terms using recent studies from environmental and health economics. The project resulted in two types of products. Infrastructure products include the extension of RFF's Haiku electricity market model to be able to accommodate a wide variety of environmental and economic policies. Infrastructure also includes revision to the Tracking and Analysis Framework (TAF), an integrated assessment model of the environmental effects of conventional pollutants. Both models

  13. Influence of Wind Plant Ancillary Voltage Control on System Small Signal Stability

    DEFF Research Database (Denmark)

    Su, Chi; Chen, Zhe

    2012-01-01

    As a common tendency, large-scale wind farms are increasingly connected to the transmission system of modern power grids. This introduces some new challenges to the connected power systems, and the transmission system operators (TSOs) have to put some new requirements as part of the grid codes on...... the integration of wind farms. One common requirement to wind farms is the function of system voltage control which can be implemented in the grid-side convertor controller of a variable speed wind turbine. This ancillary voltage control provided by wind farms could have some influence on the system...

  14. Ancillary Frequency Control of Direct Drive Full-Scale Converter Based Wind Power Plants

    OpenAIRE

    Hu, Weihao; Su, Chi; Fang, Jiakun; Chen, Zhe; Hu, Yanting

    2013-01-01

    This paper presents a simulation model of a wind power plant based on a MW-level variable speed wind turbine with a full-scale back-to-back power converter developed in the simulation tool of DIgSILENT Power Factory. Three different kinds of ancillary frequency control strategies, namely inertia emulation, primary frequency control and secondary frequency control, are proposed in order to improve the frequency stability of power systems. The modified IEEE 39-bus test system with a large-scale...

  15. Molecular Structure Laboratory. Fourier Transform Nuclear Magnetic Resonance (FTNMR) Spectrometer and Ancillary Instrumentation at SUNY Geneseo

    Energy Technology Data Exchange (ETDEWEB)

    Geiger, David K [State Univ. of New York (SUNY), Geneseo, NY (United States)

    2015-12-31

    An Agilent 400-MR nuclear magnetic resonance (NMR) spectrometer and ancillary equipment were purchased, which are being used for molecular structure elucidation.  The instrumentation is housed in a pre-existing facility designed specifically for its use. This instrument package is being used to expand the research and educational efforts of the faculty and students at SUNY-Geneseo and is made available to neighboring educational institutions and business concerns.  Funds were also used for training of College personnel, maintenance of the instrumentation, and installation of the equipment.

  16. Subunit architecture of general transcription factor TFIIH

    OpenAIRE

    Gibbons, Brian J.; Brignole, Edward J; Azubel, Maia; Murakami, Kenji; Voss, Neil R; Bushnell, David A.; Asturias, Francisco J; Kornberg, Roger D.

    2012-01-01

    Structures of complete 10-subunit yeast TFIIH and of a nested set of subcomplexes, containing 5, 6, and 7 subunits, have been determined by electron microscopy (EM) and 3D reconstruction. Consistency among all the structures establishes the location of the “minimal core” subunits (Ssl1, Tfb1, Tfb2, Tfb4, and Tfb5), and additional densities can be specifically attributed to Rad3, Ssl2, and the TFIIK trimer. These results can be further interpreted by placement of previous X-ray structures into...

  17. An integrated pan-European ancillary services market for frequency control

    International Nuclear Information System (INIS)

    Real-time balancing of mismatches between consumption and production is one of the key elements for the secure operation of power systems. This takes place within the framework of ancillary services managed by respective national transmission system operating companies. The objective of this paper is to investigate the option of one integrated pan-European ancillary services market. Our contribution is twofold: quantifying the potential benefit of such an option and outlining a possible approach to such an option highlighting its positive properties as well as risks and challenges. In several recently published considerations of pan-European electricity supply models this topic has not been adequately addressed, but we believe it is one of the crucial subjects in shaping the future electricity supply in Europe. -- Author-Highlights: •We investigated the option of a one-area market for frequency control in Continental Europe. •For the current situation a centralised approach may lead to a significant reduction of control reserves. •In the long run it is a possibility to avoid a tremendous increase of needed control reserves. •The implementation of an integrated market is not to be underestimated

  18. MR imaging diagnosis of posterior cruciate ligament injury: importance of ancillary findings

    International Nuclear Information System (INIS)

    To evaluate the importance of two ancillary findings of anterior tibial plateau bruise/fracture and popliteus muscle strain on MR diagnosis of posterior cruicate ligament injury. We retrospectively evaluated 48 patients with confirmed posterior cruciate ligament tear. We studied the incidence of anterior tibial plateau injury and popliteus muscle strain, and the specificity of popliteus muscle strain with or without bony injury. A complete tear of the posterior cruciate ligament was noted in 37 cases, a partial tear in 11. Anterior tibial plateau lesion was found in 21 of 48 cases (44%); This total was made up of 17/37 PCL complete tears (46%) and 4/11 partial tears (36%). The difference in the incidence of complete and partial tears is not statistically significant. Popliteus muscle injury was found in 20 of 48 cases (42%), the total consisted of 19/37 PCL complete tears (51%) and 1/11 partial tears (10%). The incidence of 42% is relatively high, approximating that of bony injury. The difference in the incidence of complete and partial tears is statistically significant (p < 0.006). Specificity for posterior cruciate ligament tear is 69%(20/29), and when concomitant with anterior tibial plateau injury is 94%(16/17). As in the case of anterior cruciate ligament injury, these documented ancillary findings of anterior tibial plateau and popliteus muscle injuries are very helpful when MR diagnosis of posterior cruciate ligament injury itself and differentiation of partial and complete rupture are doubtful

  19. MR imaging diagnosis of posterior cruciate ligament injury: importance of ancillary findings

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Kang Ik; Lee, Jong Hwa; Kim, Young Sun; Lee, Jung Hwoi; Ki, Tae Sung [Ulsan Univ. Hospital, Seoul (Korea, Republic of); Park, Jong Oag [Daejun Sungsim Hospital, Daejun (Korea, Republic of)

    1997-04-01

    To evaluate the importance of two ancillary findings of anterior tibial plateau bruise/fracture and popliteus muscle strain on MR diagnosis of posterior cruicate ligament injury. We retrospectively evaluated 48 patients with confirmed posterior cruciate ligament tear. We studied the incidence of anterior tibial plateau injury and popliteus muscle strain, and the specificity of popliteus muscle strain with or without bony injury. A complete tear of the posterior cruciate ligament was noted in 37 cases, a partial tear in 11. Anterior tibial plateau lesion was found in 21 of 48 cases (44%); This total was made up of 17/37 PCL complete tears (46%) and 4/11 partial tears (36%). The difference in the incidence of complete and partial tears is not statistically significant. Popliteus muscle injury was found in 20 of 48 cases (42%), the total consisted of 19/37 PCL complete tears (51%) and 1/11 partial tears (10%). The incidence of 42% is relatively high, approximating that of bony injury. The difference in the incidence of complete and partial tears is statistically significant (p < 0.006). Specificity for posterior cruciate ligament tear is 69%(20/29), and when concomitant with anterior tibial plateau injury is 94%(16/17). As in the case of anterior cruciate ligament injury, these documented ancillary findings of anterior tibial plateau and popliteus muscle injuries are very helpful when MR diagnosis of posterior cruciate ligament injury itself and differentiation of partial and complete rupture are doubtful.

  20. Open Automated Demand Response Communications in Demand Response for Wholesale Ancillary Services

    Energy Technology Data Exchange (ETDEWEB)

    Kiliccote, Sila; Piette, Mary Ann; Ghatikar, Girish; Koch, Ed; Hennage, Dan; Hernandez, John; Chiu, Albert; Sezgen, Osman; Goodin, John

    2009-11-06

    The Pacific Gas and Electric Company (PG&E) is conducting a pilot program to investigate the technical feasibility of bidding certain demand response (DR) resources into the California Independent System Operator's (CAISO) day-ahead market for ancillary services nonspinning reserve. Three facilities, a retail store, a local government office building, and a bakery, are recruited into the pilot program. For each facility, hourly demand, and load curtailment potential are forecasted two days ahead and submitted to the CAISO the day before the operation as an available resource. These DR resources are optimized against all other generation resources in the CAISO ancillary service. Each facility is equipped with four-second real time telemetry equipment to ensure resource accountability and visibility to CAISO operators. When CAISO requests DR resources, PG&E's OpenADR (Open Automated DR) communications infrastructure is utilized to deliver DR signals to the facilities energy management and control systems (EMCS). The pre-programmed DR strategies are triggered without a human in the loop. This paper describes the automated system architecture and the flow of information to trigger and monitor the performance of the DR events. We outline the DR strategies at each of the participating facilities. At one site a real time electric measurement feedback loop is implemented to assure the delivery of CAISO dispatched demand reductions. Finally, we present results from each of the facilities and discuss findings.

  1. Immunohistochemistry and other ancillary techniques in the diagnosis of gestational trophoblastic diseases.

    Science.gov (United States)

    Buza, Natalia; Hui, Pei

    2014-05-01

    Gestational trophoblastic disease (GTD) encompasses entities ranging from ubiquitous hydatidiform moles to rare neoplastic gestational trophoblastic tumors. In practice, the histological diagnosis of GTD continues to have significant diagnostic inaccuracy with marked inter- and intra-observer variability, even among expert pathologists. Studies in correlation with genotypic evidence have confirmed a lack of accuracy in diagnosis of hydatidiform moles using histology alone. Applications of new immunohistochemical markers and molecular techniques have significantly enhanced the diagnostic precision of various GTDs in recent years. p57 Immunohistochemistry is a highly useful marker in confirming complete hydatidiform mole. PCR-based DNA genotyping has emerged as a powerful diagnostic measure to precisely classify both complete and partial hydatidiform moles. With acquisition of molecular diagnostic capabilities at most medical centers, these ancillary techniques have been increasingly integrated into the routine diagnostic workup of GTD. We propose an algorithmic approach combining histology and these ancillary tests to provide the best diagnostic practice possible. Under this algorithm, all cases with histological suspicion for complete mole are subject to p57 immunohistochemical confirmation, and all cases with histological suspicion for partial mole undergo DNA genotyping workup. Beyond hydatidiform mole, recognition of gestational trophoblastic tumors requires a high index of suspicion and application of immunohistochemical markers of trophoblast is helpful to accurately diagnose these rare tumors. PMID:24907943

  2. Access to Emissions Distributions and Related Ancillary Data through the ECCAD database

    Science.gov (United States)

    Darras, Sabine; Enriquez, Edgar; Granier, Claire; Liousse, Catherine; Boulanger, Damien; Fontaine, Alain

    2016-04-01

    The ECCAD database (Emissions of atmospheric Compounds and Compilation of Ancillary Data) provides a user-friendly access to global and regional surface emissions for a large set of chemical compounds and ancillary data (land use, active fires, burned areas, population,etc). The emissions inventories are time series gridded data at spatial resolution from 1x1 to 0.1x0.1 degrees. ECCAD is the emissions database of the GEIA (Global Emissions InitiAtive) project and a sub-project of the French Atmospheric Data Center AERIS (http://www.aeris-data.fr). ECCAD has currently more than 2200 users originating from more than 80 countries. The project benefits from this large international community of users to expand the number of emission datasets made available. ECCAD provides detailed metadata for each of the datasets and various tools for data visualization, for computing global and regional totals and for interactive spatial and temporal analysis. The data can be downloaded as interoperable NetCDF CF-compliant files, i.e. the data are compatible with many other client interfaces. The presentation will provide information on the datasets available within ECCAD, as well as examples of the analysis work that can be done online through the website: http://eccad.aeris-data.fr.

  3. Binding of CFA/I Pili of Enterotoxigenic Escherichia coli to Asialo-GM1 Is Mediated by the Minor Pilin CfaE.

    Science.gov (United States)

    Madhavan, T P Vipin; Riches, James D; Scanlon, Martin J; Ulett, Glen C; Sakellaris, Harry

    2016-05-01

    CFA/I pili are representatives of a large family of related pili that mediate the adherence of enterotoxigenic Escherichia coli to intestinal epithelial cells. They are assembled via the alternate chaperone-usher pathway and consist of two subunits, CfaB, which makes up the pilus shaft and a single pilus tip-associated subunit, CfaE. The current model of pilus-mediated adherence proposes that CFA/I has two distinct binding activities; the CfaE subunit is responsible for binding to receptors of unknown structure on erythrocyte and intestinal epithelial cell surfaces, while CfaB binds to various glycosphingolipids, including asialo-GM1. In this report, we present two independent lines of evidence that, contrary to the existing model, CfaB does not bind to asialo-GM1 independently of CfaE. Neither purified CfaB subunits nor CfaB assembled into pili bind to asialo-GM1. Instead, we demonstrate that binding activity toward asialo-GM1 resides in CfaE and this is essential for pilus binding to Caco-2 intestinal epithelial cells. We conclude that the binding activities of CFA/I pili for asialo-GM1, erythrocytes, and intestinal cells are inseparable, require the same amino acid residues in CfaE, and therefore depend on the same or very similar binding mechanisms. PMID:26975993

  4. Risk capital allocation with autonomous subunits

    DEFF Research Database (Denmark)

    Hougaard, Jens Leth; Smilgins, Aleksandrs

    2016-01-01

    Risk capital allocation problems have been widely discussed in the academic literature. We consider a set of independent subunits collaborating in order to reduce risk: that is, when subunit portfolios are merged a diversification benefit arises and the risk of the group as a whole is smaller tha...... fairness tests related directly to the problem of risk capital allocation and show that the Lorenz set satisfies all three tests in contrast to other well-known coherent methods. Finally, we discuss how to deal with non-uniqueness of the Lorenz set.......Risk capital allocation problems have been widely discussed in the academic literature. We consider a set of independent subunits collaborating in order to reduce risk: that is, when subunit portfolios are merged a diversification benefit arises and the risk of the group as a whole is smaller than...... the sum of the risks of the individual subunits. The question is how to allocate the risk capital of the group among the subunits in a fair way. In this paper we propose to use the Lorenz set as an allocation method. We show that the Lorenz set is operational and coherent. Moreover, we propose three...

  5. An assessment of market and policy barriers for demand response providing ancillary services in U.S. electricity markets

    International Nuclear Information System (INIS)

    An impact of increased variable renewable generation is the need for balancing authorities to procure more ancillary services. While demand response resources are technically capable of providing these services, current experience across the U.S. illustrates they are relatively minor players in most regions. Accessing demand response resources for ancillary services may require a number of changes to policies and common practices at multiple levels. Regional reliability councils must first define ancillary services such that demand response resources may provide them. Once the opportunity exists, balancing authorities define and promulgate rules that set the infrastructure investments and performance attributes of a resource wishing to provide such services. These rules also dictate expected revenue streams which reveal the cost effectiveness of these resources. The regulatory compact between utility and state regulators, along with other statutes and decisions by state policymakers, may impact the interest of demand response program providers to pursue these resources as ancillary service providers. This paper identifies within these broad categories specific market and policy barriers to demand response providing ancillary services in different wholesale and retail environments, with emphasis on smaller customers who must be aggregated through a program provider to meet minimum size requirements for wholesale transactions. - Highlights: • We identify barriers keeping demand response from providing ancillary services. • Institutional, financial and program provider business model barriers exist. • Product definitions and rules do not always accommodate demand response well. • Expected revenues are uncertain and may not exceed required investments costs. • Regulatory compact and state statutes limit opportunities for program providers

  6. Utilization of Ancillary Data Sets for Conceptual SMAP Mission Algorithm Development and Product Generation

    Science.gov (United States)

    O'Neill, P.; Podest, E.

    2011-01-01

    The planned Soil Moisture Active Passive (SMAP) mission is one of the first Earth observation satellites being developed by NASA in response to the National Research Council's Decadal Survey, Earth Science and Applications from Space: National Imperatives for the Next Decade and Beyond [1]. Scheduled to launch late in 2014, the proposed SMAP mission would provide high resolution and frequent revisit global mapping of soil moisture and freeze/thaw state, utilizing enhanced Radio Frequency Interference (RFI) mitigation approaches to collect new measurements of the hydrological condition of the Earth's surface. The SMAP instrument design incorporates an L-band radar (3 km) and an L band radiometer (40 km) sharing a single 6-meter rotating mesh antenna to provide measurements of soil moisture and landscape freeze/thaw state [2]. These observations would (1) improve our understanding of linkages between the Earth's water, energy, and carbon cycles, (2) benefit many application areas including numerical weather and climate prediction, flood and drought monitoring, agricultural productivity, human health, and national security, (3) help to address priority questions on climate change, and (4) potentially provide continuity with brightness temperature and soil moisture measurements from ESA's SMOS (Soil Moisture Ocean Salinity) and NASA's Aquarius missions. In the planned SMAP mission prelaunch time frame, baseline algorithms are being developed for generating (1) soil moisture products both from radiometer measurements on a 36 km grid and from combined radar/radiometer measurements on a 9 km grid, and (2) freeze/thaw products from radar measurements on a 3 km grid. These retrieval algorithms need a variety of global ancillary data, both static and dynamic, to run the retrieval models, constrain the retrievals, and provide flags for indicating retrieval quality. The choice of which ancillary dataset to use for a particular SMAP product would be based on a number of factors

  7. Ancillary services and the integration of substantial quantities of wind power

    DEFF Research Database (Denmark)

    Østergaard, Poul Alberg

    2006-01-01

    Denmark has the World’s highest penetration of grid connected wind power in electricity generation with a share of 15.0% of total domestic demand in 2002 [Danish Energy Authority. Rapport fra arbejdsgruppen om kraftvarme- og VE-elektricitet. Bilagsrapport. Copenhagen: Danish Energy Authority; 2001......]. This is unevenly distributed in the two separate electricity systems comprising Denmark, giving a 2003 share as high as 21% in Western Denmark [Eltra. http://www.Eltra.dk. Skærbæk: Eltra; 2004] compared with a more modest 8% in the more densely populated Eastern Denmark [Elkraft System. Miljøberetning 2004...... as the potential impact of heat pumps used for district heating and installed for integration purposes. The analyses are made with particular focus on grid stability and delivery of ancillary services (required to control voltage and frequency) and demonstrate that it is possible to accommodate 50% or more wind...

  8. DMSO molecule as ancillary ligand in Ru-based catalysts for ring opening metathesis polymerization

    Energy Technology Data Exchange (ETDEWEB)

    Santana, Sirlane A.A.; Carvalho Junior, Valdemiro P.; Lima-Neto, Benedito S. [Universidade de Sao Paulo, Sao Carlos (USP), SP (Brazil). Inst. de Quimica

    2010-07-01

    The ring-opening metathesis polymerization (ROMP) of norbornene (NBE) occurs in the presence of the fac-[RuCl{sub 2}(S-DMSO){sub 3}(O-DMSO)] complex and ethyldiazoacetate (5 {mu}L), where DMSO is S- or O-bonded dimethylsulfoxide. The yield is 62% (PDI = 1.64) at room temperature for 5 min and 88% (PDI 1.93) at 50 deg C for 30 min, with [NBE]/[Ru] = 516 in CHCl{sub 3}. The yield is 90% (PDI = 1.64) in the presence of NBu{sub 4}ClO{sub 4} at room temperature for 5 min. The complex is practically inactive when one or two molecules of DMSO are replaced by pyridine, imidazole, 2-methyl-imidazole or benzimidazole. The in situ formation of the catalytic species and the behavior of the DMSO molecules as ancillary ligands in the reactivity of the RuII complexes are discussed. (author)

  9. Stable Blue Phosphorescence Iridium(III) Cyclometalated Complexes Prompted by Intramolecular Hydrogen Bond in Ancillary Ligand.

    Science.gov (United States)

    Yi, Seungjun; Kim, Jin-Hyoung; Cho, Yang-Jin; Lee, Jiwon; Choi, Tae-Sup; Cho, Dae Won; Pac, Chyongjin; Han, Won-Sik; Son, Ho-Jin; Kang, Sang Ook

    2016-04-01

    Improvement of the stability of blue phosphorescent dopant material is one of the key factors for real application of organic light-emitting diodes (OLEDs). In this study, we found that the intramolecular hydrogen bonding in an ancillary ligand from a heteroleptic Ir(III) complex can play an important role in the stability of blue phosphorescence. To rationalize the role of intramolecular hydrogen bonding, a series of Ir(III) complexes is designed and prepared: Ir(dfppy)2(pic-OH) (1a), Ir(dfppy)2(pic-OMe) (1b), Ir(ppy)2(pic-OH) (2a), and Ir(ppy)2(pic-OMe) (2b). The emission lifetime of Ir(dfppy)2(pic-OH) (1a) (τem = 3.19 μs) in dichloromethane solution was found to be significantly longer than that of Ir(dfppy)2(pic-OMe) (1b) (τem = 0.94 μs), because of a substantial difference in the nonradiative decay rate (knr = 0.28 × 10(5) s(-1) for (1a) vs 2.99 × 10(5) s(-1) for (1b)). These results were attributed to the intramolecular OH···O═C hydrogen bond of the 3-hydroxy-picolinato ligand. Finally, device lifetime was significantly improved when 1a was used as the dopant compared to FIrpic, a well-known blue dopant. Device III (1a as dopant) achieved an operational lifetime of 34.3 h for an initial luminance of 400 nits compared to that of device IV (FIrpic as dopant), a value of 20.1 h, indicating that the intramolecular hydrogen bond in ancillary ligand is playing an important role in device stability. PMID:26991672

  10. Territorial user rights for fisheries as ancillary instruments for marine coastal conservation in Chile.

    Science.gov (United States)

    Gelcich, Stefan; Fernández, Miriam; Godoy, Natalio; Canepa, Antonio; Prado, Luis; Castilla, Juan Carlos

    2012-12-01

    Territorial user rights for fisheries have been advocated as a way to achieve sustainable resource management. However, few researchers have empirically assessed their potential as ancillary marine conservation instruments by comparing them to no-take marine protected areas. In kelp (Lessonia trabeculata) forests of central Chile, we compared species richness, density, and biomass of macroinvertebrates and reef fishes among territorial-user-right areas with low-level and high-level enforcement, no-take marine protected areas, and open-access areas in 42 100-m subtidal transects. We also assessed structural complexity of the kelp forest and substratum composition. Multivariate randomized permutation tests indicated macroinvertebrate and reef fish communities associated with the different access regimes differed significantly. Substratum composition and structural complexity of kelp forest did not differ among access regimes. Univariate analyses showed species richness, biomass, and density of macroinvertebrates and reef fishes were greater in highly enforced territorial-user-right areas and no-take marine protected areas than in open-access areas. Densities of macroinvertebrates and reef fishes of economic importance were not significantly different between highly enforced territorial-user-right and no-take marine protected areas. Densities of economically important macroinvertebrates in areas with low-level enforcement were significantly lower than those in areas with high-level enforcement and no-take marine protected areas but were significantly higher than in areas with open access. Territorial-user-right areas could be important ancillary conservation instruments if they are well enforced. PMID:22971114

  11. Engineering Evaluation/Cost Analysis for the 100-N Area Ancillary Facilities and Integration Plan

    International Nuclear Information System (INIS)

    This document presents the results of an engineering evaluation/cost analysis (EE/CA) that was conducted to evaluate alternatives for addressing final disposition of contaminated buildings and structures in the 100-N Area of the Hanford Site. The Hanford Site is located in southeastern Washington State and is owned by the U.S. Government and operated by the U.S. Department of Energy, Richland Operations Office (RL). In November 1989, the 100 Area of the Hanford Site (as well as the 200, 300, and 1100 Areas) was placed on the U.S. Environmental Protection Agency's National Priorities List (NPL) under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980. The 100 Area NPL includes the 100-N Area, which is in various stages of the remediation process. It has been determined by RL that hazardous substances in the 100-N Area ancillary facilities may present a potential threat to human health or the environment, and that a non-time critical removal action at these facilities is warranted. To help determine the most appropriate action, RL, in cooperation with the Washington State Department of Ecology (Ecology) and the EPA, has prepared this EE/CA. The scope of the evaluation includes the inactive contaminated ancillary facilities in the 100-N Area, the facilities residing in the buffer zone, and the Hanford Generating Plant (HGP) and the solid waste management units (SWMUs) inside HGP support facilities. The 105-N Reactor and 109-N Heat Exchange facilities are excluded from this EE/CA evaluation

  12. Development of modified rational buyer auction for procurement of ancillary services utilizing participation matrix

    International Nuclear Information System (INIS)

    The rational buyer auction is based on a simultaneous auction that is the redesigned auction mechanism for ancillary services by the California independent system operator (CAISO). The incentive for the rational buyer auction is CAISO's intent to adopt a common sense rule of substituting higher-quality lower-cost services for lower-quality higher-cost services, when it results in reduced total procurement cost. For the purposes of designing a desirable auction where the minimum cost for the objective function as well as prevention of price reversal are achieved, either the payment cost in marginal pricing auction must be lowered or price reversal in rational buyer auction must be avoided. The objectives of this study are (a) to develop a newly proposed 'modified rational buyer' auction that does not allow price reversal and (b) to propose and validate a solution procedure that is based on participation matrix and discrete programming. The validation of the proposed solution procedure is accomplished through examination of two case studies available in the literature. Based on the first case study data, it is shown that the newly developed modified rational buyer auction avoids price reversal occurrence, while the total payment of ISO is increased by 5.8%, as compared with rational buyer auction. Also in comparison with marginal pricing auction, the ISO payment is lowered by 38.8%, when the newly developed modified rational buyer auction is utilized. For future work, it is recommended that the application of the modified rational buyer auction to joint dispatch of energy and ancillary services is investigated. (author)

  13. Development of a solid polymer electrolyte electrolysis cell module and ancillary components for a breadboard water electrolysis system

    Science.gov (United States)

    Porter, F. J., Jr.

    1972-01-01

    Solid polymer electrolyte technology in a water electrolysis system along with ancillary components to generate oxygen and hydrogen for a manned space station application are considered. Standard commercial components are utilized wherever possible. Presented are the results of investigations, surveys, tests, conclusions and recommendations for future development efforts.

  14. Planck intermediate results XXIII. Galactic plane emission components derived from Planck with ancillary data

    DEFF Research Database (Denmark)

    Ade, P. A. R.; Aghanim, N.; Arnaud, M.; Ashdown, M.; Atrio-Barandela, F.; Aumont, J.; Baccigalupi, C.; Banday, A. J.; Barreiro, R. B.; Battaner, E.; Benabed, K.; Benoit-Levy, A.; Bernard, J-P; Bersanelli, M.; Bielewicz, P.; Bobin, J.; Bonaldi, A.; Bond, J. R.; Bouchet, F. R.; Boulanger, F.; Burigana, C.; Cardoso, J-F; Catalano, A.; Chamballu, A.; Chiang, H. C.; Christensen, P. R.; Clements, D. L.; Colombi, S.; Colombo, L. P. L.; Combet, C.; Couchot, F.; Crill, B. P.; Cuttaia, F.; Danese, L.; Davies, R. D.; Davis, R. J.; de Bernardis, P.; de Rosa, A.; de Zotti, G.; Delabrouille, J.; Dickinson, C.; Diego, J. M.; Donzelli, S.; Dore, O.; Douspis, M.; Dupac, X.; Efstathiou, G.; Ensslin, T. A.; Eriksen, K.; Finelli, F.; Forni, O.; Frailis, M.; Franceschi, E.; Galeotta, S.; Ganga, K.; Genova-Santos, R. T.; Ghosh, T.; Giard, M.; Giardino, G.; Giraud-Heraud, Y.; Gonzalez-Nuevo, J.; Gorski, K. M.; Gregorio, A.; Gruppuso, A.; Hansen, F. K.; Harrison, D. L.; Henrot-Versille, S.; Herranz, D.; Hildebrandt, S. R.; Hivon, E.; Hobson, M.; Hornstrup, A.; Hovest, W.; Huffenberger, K. M.; Jaffe, A. H.; Jaffe, T. R.; Jones, W. C.; Keihanen, E.; Keskitalo, R.; Kisner, T. S.; Kneissl, R.; Knoche, J.; Kunz, M.; Kurki-Suonio, H.; Lagache, G.; Laehteenmaki, A.; Lamarre, J-M; Lasenby, A.; Lawrence, C. R.; Leonardi, R.; Liguori, M.; Lilje, P. B.; Linden-Vørnle, M.; Lopez-Caniego, M.; Lubin, P. M.; Macias-Perez, F.; Maino, D.; Mandolesi, N.; Martin, P. G.; Martinez-Gonzalez, E.; Masi, S.; Massardi, M.; Matarrese, S.; Mazzotta, P.; Meinhold, P. R.; Melchiorri, A.; Mendes, L.; Mennella, A.; Migliaccio, M.; Mitra, Susanta; Miville-Deschenes, M-A; Moneti, A.; Montier, L.; Morgante, G.; Mortlock, D.; Munshi, D.; Murphy, J. A.; Naselsky, P.; Nati, F.; Natoli, P.; Nørgaard-Nielsen, H. U.; Noviello, F.; Novikov, D.; Novikov, I.; Oxborrow, C. A.; Pagano, L.; Pajot, F.; Paladini, R.; Paoletti, D.; Pasian, F.; Pearson, T. J.; Peel, M.; Perdereau, O.; Perrotta, F.; Piacentini, F.; Piat, M.; Pierpaoli, E.; Pietrobon, D.; Plaszczynski, S.; Pointecouteau, E.; Polenta, G.; Ponthieu, N.; Popa, L.; Pratt, G. W.; Prunet, S.; Puget, J-L; Rachen, J. P.; Reach, W. T.; Rebolo, R.; Reich, W.; Reinecke, M.; Remazeilles, M.; Renault, C.; Ricciardi, S.; Riller, T.; Ristorcelli, I.; Rocha, G.; Rosset, C.; Roudier, G.; Rubino-Martin, J. A.; Rusholme, B.; Sandri, M.; Savini, G.; Scott, D.; Spencer, L. D.; Stolyarov, V.; Strong, A. W.; Sutton, D.; Suur-Uski, A-S; Sygnet, J-F; Tauber, J. A.; Tavagnacco, D.; Terenzi, L.; Tibbs, C. T.; Toffolatti, L.; Tomasi, M.; Tristram, M.; Tucci, M.; Valenziano, L.; Valiviita, J.; Van Tent, B.; Varis, J.; Vielva, P.; Villa, F.; Wade, L. A.; Wandelt, B. D.; Watson, R.; Yvon, D.; Zacchei, A.; Zonca, A.

    2015-01-01

    Planck data when combined with ancillary data provide a unique opportunity to separate the diuse emission components of the inner Galaxy.The purpose of the paper is to elucidate the morphology of the various emission components in the strong star-formation region lying inside thesolar radius and ...

  15. Heteromeric assembly of P2X subunits

    Directory of Open Access Journals (Sweden)

    Ralf Hausmann

    2013-12-01

    Full Text Available Transcripts and/or proteins of P2X receptor (P2XR subunits have been found in virtually all mammalian tissues. Generally more than one of the seven known P2X subunits have been identified in a given cell type. Six of the seven cloned P2X subunits can efficiently form functional homotrimeric ion channels in recombinant expression systems. This is in contrast to other ligand-gated ion channel families, such as the Cys-loop or glutamate receptors, where homomeric assemblies seem to represent the exception rather than the rule. P2XR mediated responses recorded from native tissues rarely match exactly the biophysical and pharmacological properties of heterologously expressed homomeric P2XRs. Heterotrimerization of P2X subunits is likely to account for this observed diversity. While the existence of heterotrimeric P2X2/3Rs and their role in physiological processes is well established, the composition of most other P2XR heteromers and/or the interplay between distinct trimeric receptor complexes in native tissues is not clear. After a description of P2XR assembly and the structure of the intersubunit ATP-binding site, this review summarizes the distribution of P2XR subunits in selected mammalian cell types and the biochemically and/or functionally characterized heteromeric P2XRs that have been observed upon heterologous co-expression of P2XR subunits. We further provide examples where the postulated heteromeric P2XRs have been suggested to occur in native tissues and an overview of the currently available pharmacological tools that have been used to discriminate between homo- and heteromeric P2XRs

  16. Preliminary Results of Ancillary Safety Analyses Supporting TREAT LEU Conversion Activities

    Energy Technology Data Exchange (ETDEWEB)

    Brunett, A. J. [Argonne National Lab. (ANL), Argonne, IL (United States); Fei, T. [Argonne National Lab. (ANL), Argonne, IL (United States); Strons, P. S. [Argonne National Lab. (ANL), Argonne, IL (United States); Papadias, D. D. [Argonne National Lab. (ANL), Argonne, IL (United States); Hoffman, E. A. [Argonne National Lab. (ANL), Argonne, IL (United States); Kontogeorgakos, D. C. [Argonne National Lab. (ANL), Argonne, IL (United States); Connaway, H. M. [Argonne National Lab. (ANL), Argonne, IL (United States); Wright, A. E. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-10-01

    The Transient Reactor Test Facility (TREAT), located at Idaho National Laboratory (INL), is a test facility designed to evaluate the performance of reactor fuels and materials under transient accident conditions. The facility, an air-cooled, graphite-moderated reactor designed to utilize fuel containing high-enriched uranium (HEU), has been in non-operational standby status since 1994. Currently, in support of the missions of the Department of Energy (DOE) National Nuclear Security Administration (NNSA) Material Management and Minimization (M3) Reactor Conversion Program, a new core design is being developed for TREAT that will utilize low-enriched uranium (LEU). The primary objective of this conversion effort is to design an LEU core that is capable of meeting the performance characteristics of the existing HEU core. Minimal, if any, changes are anticipated for the supporting systems (e.g. reactor trip system, filtration/cooling system, etc.); therefore, the LEU core must also be able to function with the existing supporting systems, and must also satisfy acceptable safety limits. In support of the LEU conversion effort, a range of ancillary safety analyses are required to evaluate the LEU core operation relative to that of the existing facility. These analyses cover neutronics, shielding, and thermal hydraulic topics that have been identified as having the potential to have reduced safety margins due to conversion to LEU fuel, or are required to support the required safety analyses documentation. The majority of these ancillary tasks have been identified in [1] and [2]. The purpose of this report is to document the ancillary safety analyses that have been performed at Argonne National Laboratory during the early stages of the LEU design effort, and to describe ongoing and anticipated analyses. For all analyses presented in this report, methodologies are utilized that are consistent with, or improved from, those used in analyses for the HEU Final Safety Analysis

  17. Immunochemical aspects of crotoxim and its subunits

    International Nuclear Information System (INIS)

    Crotamine and crotoxin with the subunits - phospholipase A and crotapotin - were obtained by purification from Crotalus durissus terrificus venom. Interaction studies of the subunits using crotalic antiserum, indicated that: crotoxin is formed of crotapotin and phospholipase A with the molar ratio of 1 to 1; using crotapotin 125I the presence of a soluble complex was shown with the same antiserum. Immunological precipitation reactions demonstrated that crotapotin is antigenic: crotapotin and phospholipase A presented similar antigenic determinants; crotoxin antiserum reacted with each one of the submits; when the subunits are mixed to form synthetic crotoxin some antigenic determinants are masked in the process of interaction. Crotamine, interacted with crotapotin 1:1, without hidden antigenic determinants crotapotin antigenic site seems to be formed by, at least, one lysine. Enzimatical activity of phospholipase A apreared to be dependent on some reaction conditions when its arginine residues are blocked. Tyrosines of phospholipase A are more susceptible to labelling with 131I than crotapotin. Gama irradiation of aqueous solutions of the subunits produced modifications in the ultraviolet spectra. A decrease of the enzymatic activity occured as a function of radiation dosis. Immunological activities of crotapotin and phospholipase A were not altered

  18. Automated ancillary cancer history classification for mesothelioma patients from free-text clinical reports

    Directory of Open Access Journals (Sweden)

    Richard A Wilson

    2010-01-01

    Full Text Available Background: Clinical records are often unstructured, free-text documents that create information extraction challenges and costs. Healthcare delivery and research organizations, such as the National Mesothelioma Virtual Bank, require the aggregation of both structured and unstructured data types. Natural language processing offers techniques for automatically extracting information from unstructured, free-text documents. Methods: Five hundred and eight history and physical reports from mesothelioma patients were split into development (208 and test sets (300. A reference standard was developed and each report was annotated by experts with regard to the patient′s personal history of ancillary cancer and family history of any cancer. The Hx application was developed to process reports, extract relevant features, perform reference resolution and classify them with regard to cancer history. Two methods, Dynamic-Window and ConText, for extracting information were evaluated. Hx′s classification responses using each of the two methods were measured against the reference standard. The average Cohen′s weighted kappa served as the human benchmark in evaluating the system. Results: Hx had a high overall accuracy, with each method, scoring 96.2%. F-measures using the Dynamic-Window and ConText methods were 91.8% and 91.6%, which were comparable to the human benchmark of 92.8%. For the personal history classification, Dynamic-Window scored highest with 89.2% and for the family history classification, ConText scored highest with 97.6%, in which both methods were comparable to the human benchmark of 88.3% and 97.2%, respectively. Conclusion: We evaluated an automated application′s performance in classifying a mesothelioma patient′s personal and family history of cancer from clinical reports. To do so, the Hx application must process reports, identify cancer concepts, distinguish the known mesothelioma from ancillary cancers, recognize negation

  19. Integrated Stormwater Management in Los Angeles, California: Best Management Practices and Evaluation of Ancillary Benefits

    Science.gov (United States)

    Hogue, T. S.

    2014-12-01

    Best Management Practices (BMPs) and Low Impact Development (LID) have been the primary tools to address quantitative and qualitative surface runoff impacts. The City of Los Angeles (City) is evaluating plans for individual Total Maximum Daily Load (TMDL) pollutants in each of its major watersheds. However, it has yet to be studied if implementing individual BMP projects will adequately address water quality objectives for receiving (downstream) water bodies, such as Ballona Creek, Ballona Estuary and the Santa Monica Bay. In addition, there is significant uncertainty surrounding potential ancillary benefits (flood reduction, water supply, green space, etc.) from BMP/LID implementation. This presentation will overview our work with the City evaluating the influence of BMPs and LIDs in improving water quality at the watershed scale as well as quantifying other hydrologic benefits. Multiple BMP scenarios are considered to identify various pathways toward improved receiving water body quality in Ballona Creek and Dominquez watersheds. Specific study objectives are to: 1) identify suites of BMP scenarios which can lead to TMDL compliance, 2) quantify the multiple benefits provided by BMPs beyond their primary water quality improvement purpose, and 3) evaluate the success of using existing software for watershed-scale BMP modeling. Our goal is to provide realistic, implementable pathways that can be used by stakeholders to help plan for future education, outreach and capital improvement programs as well as determine feasible pollutant reduction objectives.

  20. Disaggregating census data for population mapping using random forests with remotely-sensed and ancillary data.

    Directory of Open Access Journals (Sweden)

    Forrest R Stevens

    Full Text Available High resolution, contemporary data on human population distributions are vital for measuring impacts of population growth, monitoring human-environment interactions and for planning and policy development. Many methods are used to disaggregate census data and predict population densities for finer scale, gridded population data sets. We present a new semi-automated dasymetric modeling approach that incorporates detailed census and ancillary data in a flexible, "Random Forest" estimation technique. We outline the combination of widely available, remotely-sensed and geospatial data that contribute to the modeled dasymetric weights and then use the Random Forest model to generate a gridded prediction of population density at ~100 m spatial resolution. This prediction layer is then used as the weighting surface to perform dasymetric redistribution of the census counts at a country level. As a case study we compare the new algorithm and its products for three countries (Vietnam, Cambodia, and Kenya with other common gridded population data production methodologies. We discuss the advantages of the new method and increases over the accuracy and flexibility of those previous approaches. Finally, we outline how this algorithm will be extended to provide freely-available gridded population data sets for Africa, Asia and Latin America.

  1. Disaggregating census data for population mapping using random forests with remotely-sensed and ancillary data.

    Science.gov (United States)

    Stevens, Forrest R; Gaughan, Andrea E; Linard, Catherine; Tatem, Andrew J

    2015-01-01

    High resolution, contemporary data on human population distributions are vital for measuring impacts of population growth, monitoring human-environment interactions and for planning and policy development. Many methods are used to disaggregate census data and predict population densities for finer scale, gridded population data sets. We present a new semi-automated dasymetric modeling approach that incorporates detailed census and ancillary data in a flexible, "Random Forest" estimation technique. We outline the combination of widely available, remotely-sensed and geospatial data that contribute to the modeled dasymetric weights and then use the Random Forest model to generate a gridded prediction of population density at ~100 m spatial resolution. This prediction layer is then used as the weighting surface to perform dasymetric redistribution of the census counts at a country level. As a case study we compare the new algorithm and its products for three countries (Vietnam, Cambodia, and Kenya) with other common gridded population data production methodologies. We discuss the advantages of the new method and increases over the accuracy and flexibility of those previous approaches. Finally, we outline how this algorithm will be extended to provide freely-available gridded population data sets for Africa, Asia and Latin America. PMID:25689585

  2. Proposal for a change of contractor to operate the hostels, apartments and ancillary premises

    CERN Document Server

    2001-01-01

    The purpose of this document is to inform the Finance Committee of the final outcome of the negotiations with the firm to which the contract was adjudicated for the operation of the hostels, apartments and ancillary premises run by the CERN Housing Service and to request approval for the contract placed with the second lowest bidder. In September 2000, the Finance Committee agreed to the negotiation of a contract with VIENNA INTERNATIONAL HOTEL MANAGEMENT (AT) - SEREG (CH) (cf. CERN/FC/4311). For the reasons explained in this document, the Finance Committee is now invited to approve a contract with the consortium ISS MULTISERVICE (CH) - ISS GEBAEUDESERVICE (DE), the second lowest bidder, for an initial period of five years, from 1 January 2001, for a total amount of 7 206 000 Swiss francs, not subject to revision until 31 December 2001. The contract includes an option for two one-year extensions beyond the initial five-year period. The consortium has indicated the following distribution by country of the cont...

  3. Cost-Causation-Based Tariffs for Wind Ancillary Service Impacts: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Kirby, B.; Milligan, M.; Wan, Y.

    2006-06-01

    Conference paper discussing the integration cost of wind. Although specific tariffs for wind generation for ancillary services are uncommon, we anticipate that balancing authorities (control areas) and other entities will move toward such tariffs. Tariffs for regulation and imbalance services should be cost-based, recognize the relevant time scales that correspond with utility operational cycles, and properly allocate those costs to those entities that cause the balancing authority to incur the costs. In this paper, we present methods for separating wind's impact into regulation and load following (imbalance) time scales. We show that approximating these impacts with simpler methods can significantly distort cost causation and even cause confusion between the relevant time scales. We present results from NREL's wind data collection program to illustrate the dangers of linearly scaling wind resource data from small wind plants to approximate the wind resource data from large wind plants. Finally, we provide a framework for developing regulation and imbalance tariffs, we outline methods to begin examining contingency reserve requirements for wind plants, we provide guidance on the important characteristics to consider, and we provide hypothetical cases that the tariff can be tested against to determine whether the results are desired.

  4. Workshop on environmental assessment. [Regulation of applications of nuclear energy and related ancillary systems

    Energy Technology Data Exchange (ETDEWEB)

    Watson, E.C. (comp.)

    1982-07-01

    Objectives of the workshop were: to review and evaluate the state-of-the-art of environmental impact assessments as applied to the regulation of applications of nuclear energy and related ancillary systems; to identify areas where existing technology allows establishing acceptable methods or standard practices that will meet the requirements of the NRC regulations, standards and guides for both normal operations and off-standard conditions including accident considerations; to illuminate topics where existing models or analytical methods are deficient because of unverified assumptions, a paucity of empirical data, conflicting results reported in the literature or a need for observation of operation systems; to compile, analyze and synthesize a prioritized set of research needs to advance the state-of-the-art to the level which will meet all of the requirements of the Commission's regulations, standards and guides; and to develop bases for maintaining the core of regulatory guidance at the optimum level balancing technical capabilities with practical considerations of cost and value to the regulatory process. The discussion held in small group sessions on aquatic, atmospheric, and terrestrial pathways are presented. The following research needs were identified as common to all three groups: validation of models; characterization of source terms; development of screening techniques; basis for de minimis levels of contamination; and updating of objectives for environmental monitoring programs.

  5. Integrated Power Management of Conventional Units and Industrial Loads in China’s Ancillary Services Scheduling

    Directory of Open Access Journals (Sweden)

    Mingtao Yao

    2015-05-01

    Full Text Available With the development of the smart grid in China, new opportunities for responsive industrial loads to participate in the provision of ancillary services (AS will become accessible. This paper summarizes AS in China and analyzes the necessary characteristics and advantages of industrial users to provide AS according to their response mechanism. Cement manufacturing and aluminum smelter processes are selected as two representatives of responsive industrial loads. An agent-based model that includes generation, industrial user, and grid agents is proposed. Using two case studies, we analyze the integrated power management of conventional units and industrial loads in day-ahead and real-time AS scheduling based on real device parameters, price mechanisms and production data. The simulation results indicate that the participation of responsive industrial loads in the provision of AS, in China, can improve the coal consumption rate and the system-wide load factor as well as reduce the total system cost for the provision of AS significantly.

  6. Impact of Production from Photovoltaic Power Plants on Increase of Ancillary Services in the Czech Republic

    Directory of Open Access Journals (Sweden)

    Martin Smocek

    2016-01-01

    Full Text Available Renewable energy resources represent a noticeable part of the overall energetic concept development. New integration of renewable energy resources into power grids has a significant impact on the reliability and quality of power supply. The major problem of the photovoltaic and wind power plants is their dependency on weather conditions, since it has a direct effect on their immediate output produced that shows stochastic behaviour. These stochastic outputs result in very adverse impacts on the power grid. Further development of these resources could lead to exceeding of the control and absorption abilities of the power grid. The power grid must be set in balance with respect to the production and consumption of electric power at any time. The operation of photovoltaic power plants impair keeping this balance. That has an adverse impact on the very operation and maintenance of network parameters within the extent required. This survey deals with analysis focused on operation of the photovoltaic power plants with respect to the increase of reserve power in ancillary services in the Czech Republic.

  7. Planck intermediate results. XXIII. Galactic plane emission components derived from Planck with ancillary data

    CERN Document Server

    Ade, P A R; Alves, M I R; Arnaud, M; Ashdown, M; Atrio-Barandela, F; Aumont, J; Baccigalupi, C; Banday, A J; Barreiro, R B; Battaner, E; Benabed, K; Benoit-Lévy, A; Bernard, J -P; Bersanelli, M; Bielewicz, P; Bobin, J; Bonaldi, A; Bond, J R; Bouchet, F R; Boulanger, F; Burigana, C; Cardoso, J -F; Catalano, A; Chamballu, A; Chiang, H C; Christensen, P R; Clements, D L; Colombi, S; Colombo, L P L; Combet, C; Couchot, F; Crill, B P; Cuttaia, F; Danese, L; Davies, R D; Davis, R J; de Bernardis, P; de Rosa, A; de Zotti, G; Delabrouille, J; Dickinson, C; Diego, J M; Donzelli, S; Doré, O; Douspis, M; Dupac, X; Efstathiou, G; Enßlin, T A; Eriksen, H K; Finelli, F; Forni, O; Frailis, M; Franceschi, E; Galeotta, S; Ganga, K; Génova-Santos, R T; Ghosh, T; Giard, M; Giardino, G; Giraud-Héraud, Y; González-Nuevo, J; Górski, K M; Gregorio, A; Gruppuso, A; Hansen, F K; Harrison, D L; Henrot-Versillé, S; Herranz, D; Hildebrandt, S R; Hivon, E; Hobson, M; Hornstrup, A; Hovest, W; Huffenberger, K M; Jaffe, A H; Jaffe, T R; Jones, W C; Keihänen, E; Keskitalo, R; Kisner, T S; Kneissl, R; Knoche, J; Kunz, M; Kurki-Suonio, H; Lagache, G; Lähteenmäki, A; Lamarre, J -M; Lasenby, A; Lawrence, C R; Leonardi, R; Liguori, M; Lilje, P B; Linden-Vørnle, M; López-Caniego, M; Lubin, P M; Macías-Pérez, J F; Maino, D; Mandolesi, N; Martin, P G; Martínez-González, E; Masi, S; Massardi, M; Matarrese, S; Mazzotta, P; Meinhold, P R; Melchiorri, A; Mendes, L; Mennella, A; Migliaccio, M; Mitra, S; Miville-Deschênes, M -A; Moneti, A; Montier, L; Morgante, G; Mortlock, D; Munshi, D; Murphy, J A; Naselsky, P; Nati, F; Natoli, P; Nørgaard-Nielsen, H U; Noviello, F; Novikov, D; Novikov, I; Oxborrow, C A; Pagano, L; Pajot, F; Paladini, R; Paoletti, D; Pasian, F; Pearson, T J; Peel, M; Perdereau, O; Perrotta, F; Piacentini, F; Piat, M; Pierpaoli, E; Pietrobon, D; Plaszczynski, S; Pointecouteau, E; Polenta, G; Ponthieu, N; Popa, L; Pratt, G W; Prunet, S; Puget, J -L; Rachen, J P; Reach, W T; Rebolo, R; Reich, W; Reinecke, M; Remazeilles, M; Renault, C; Ricciardi, S; Riller, T; Ristorcelli, I; Rocha, G; Rosset, C; Roudier, G; Rubiño-Martín, J A; Rusholme, B; Sandri, M; Savini, G; Scott, D; Spencer, L D; Stolyarov, V; Strong, A W; Sutton, D; Suur-Uski, A -S; Sygnet, J -F; Tauber, J A; Tavagnacco, D; Terenzi, L; Tibbs, C T; Toffolatti, L; Tomasi, M; Tristram, M; Tucci, M; Valenziano, L; Valiviita, J; Van Tent, B; Varis, J; Vielva, P; Villa, F; Wade, L A; Wandelt, B D; Watson, R; Yvon, D; Zacchei, A; Zonca, A

    2014-01-01

    Planck data when combined with ancillary data provide a unique opportunity to separate the diffuse emission components of the inner Galaxy. The purpose of the paper is to elucidate the morphology of the various emission components in the strong star-formation region lying inside the solar radius and to clarify the relationship between the various components. The region of the Galactic plane covered is l=300-0-60deg where star-formation is highest and the emission is strong enough to make meaningful component separation. The latitude widths in this longitude range lie between 1deg and 2deg, which correspond to FWHM z-widths of 100-200pc at a typical distance of 6kpc. The four emission components studied here are synchrotron, free-free, anomalous microwave emission (AME), and thermal (vibrational) dust emission. These components are identified by constructing spectral energy distributions (SEDs) at positions along the Galactic plane using the wide frequency coverage of Planck (28.4-857GHz) in combination with l...

  8. Electric industry restructuring, ancillary services, and the potential impact on wind

    Energy Technology Data Exchange (ETDEWEB)

    Kirby, B.; Hirst, E. [Oak Ridge National Lab., TN (United States); Parsons, B.; Porter, K. [National Renewable Energy Lab., Golden, CO (United States)] [and others

    1997-12-31

    The new competitive electric power environment raises increased challenges for wind power. The DOE and EPRI wind programs have dealt extensively with the traditional vertically integrated utility planning and operating environment in which the host utility owns the generation (or purchases the power) and provides dispatch and transmission services. Under this traditional environment, 1794 MW of wind power, principally in California, have been successfully integrated into the U.S. electric power system. Another 4200 MW are installed elsewhere in the world. As issues have arisen, such as intermittency and voltage regulation, they have been successfully addressed with accepted power system procedures and practices. For an intermittent, non-dispatchable resource such as wind, new regulatory rules affecting power transmission services, raise questions about which ancillary services wind plants will be able to sell, which they will be required to purchase, and what the economic impacts will be on individual wind projects. This paper begins to look at issues of concern to wind in a restructured electric industry. The paper first briefly looks at the range of unbundled services and comments on their unique significance to wind. To illustrate the concerns that arise with restructuring, the paper then takes a more detailed look at a single service: regulation. Finally, the paper takes a brief look at technologies and strategies that could improve the competitive position of wind.

  9. Current perspectives on the use of ancillary materials for the manufacture of cellular therapies.

    Science.gov (United States)

    Solomon, Jennifer; Csontos, Lynn; Clarke, Dominic; Bonyhadi, Mark; Zylberberg, Claudia; McNiece, Ian; Kurtzberg, Joanne; Bell, Rosemarie; Deans, Robert

    2016-01-01

    Continued growth in the cell therapy industry and commercialization of cell therapies that successfully advance through clinical trials has led to increased awareness around the need for specialized and complex materials utilized in their manufacture. Ancillary materials (AMs) are components or reagents used during the manufacture of cell therapy products but are not intended to be part of the final products. Commonly, there are limitations in the availability of clinical-grade reagents used as AMs. Furthermore, AMs may affect the efficacy of the cell product and subsequent safety of the cell therapy for the patient. As such, AMs must be carefully selected and appropriately qualified during the cell therapy development process. However, the ongoing evolution of cell therapy research, limited number of clinical trials and registered cell therapy products results in the current absence of specific regulations governing the composition, compliance, and qualification of AMs often leads to confusion by suppliers and users in this field. Here we provide an overview and interpretation of the existing global framework surrounding AM use and investigate some common misunderstandings within the industry, with the aim of facilitating the appropriate selection and qualification of AMs. The key message we wish to emphasize is that in order to most effectively mitigate risk around cell therapy development and patient safety, users must work with their suppliers and regulators to qualify each AM to assess source, purity, identity, safety, and suitability in a given application. PMID:26596503

  10. Analysis of the Effects of a Flexible Ramping Ancillary Service Product on Power System Operations: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Krad, Ibrahim; Ibanez, Eduardo; Ela, Erik

    2015-10-19

    The recent increased interest in utilizing variable generation (VG) resources such as wind and solar in power systems has motivated investigations into new operating procedures. Although these resources provide desirable value to a system (e.g., no fuel costs or emissions), interconnecting them provides unique challenges. Their variable, non-controllable nature in particular requires significant attention, because it directly results in increased power system variability and uncertainty. One way to handle this is via new operating reserve schemes. Operating reserves provide upward and downward generation and ramping capacity to counteract uncertainty and variability prior to their realization. For instance, uncertainty and variability in real-time dispatch can be accounted for in the hour-ahead unit commitment. New operating reserve methodologies that specifically account for the increased variability and uncertainty caused by VG are currently being investigated and developed by academia and industry. This paper examines one method inspired by the new operating reserve product being proposed by the California Independent System Operator. The method is based on examining the potential ramping requirements at any given time and enforcing those requirements via a reserve demand curve in the market-clearing optimization as an additional ancillary service product.

  11. Dynamic regulation of β1 subunit trafficking controls vascular contractility

    OpenAIRE

    Leo, M. Dennis; Bannister, John P.; Narayanan, Damodaran; Nair, Anitha; Grubbs, Jordan E.; Gabrick, Kyle S.; Boop, Frederick A.; Jaggar, Jonathan H.

    2014-01-01

    Plasma membrane ion channels composed of pore-forming and auxiliary subunits regulate physiological functions in virtually all cell types. A conventional view is that ion channels assemble with their auxiliary subunits prior to surface trafficking of the multiprotein complex. Arterial myocytes express large-conductance Ca2+-activated potassium (BK) channel α and auxiliary β1 subunits that modulate contractility and blood pressure and flow. The data here show that although most BKα subunits ar...

  12. Removal Action Workplan for the 105-DR and 105-F Building Interim Safe Storage Projects and Ancillary Buildings

    International Nuclear Information System (INIS)

    This document is the removal action workplan (RAW) for the 105-DR and 105-F Reactor Buildings and ancillary facilities. These buildings and facilities are located in the 100-D/DR and 100-F Areas of the Hanford Site in Benton County, Washington, which is owned and operated by the U.S. Department of Energy (DOE). The 100 Areas (including 100-D/DR and 100-F Areas) of the Hanford Site were placed on the U.S. Environmental Protection Agency's (EPA) National Priorities List under the Comprehensive Environmental Response, Compensation,and Liability Act of 1980 (CERCLA). DOE has determined that hazardous substances in the 105-DR and 105-F Reactor Buildings and four ancillary facilities present a potential threat to human health or the environment DOE has also determined that a non-time critical removal action is warranted at these facilities

  13. Pump Storage Hydropower for delivering Balancing Power and Ancillary Services - A Case Study of Illvatn Pump Storage Power Plant

    OpenAIRE

    Norang, Ingunn

    2015-01-01

    The power markets in Europe are changing rapidly. The drastic shift towards renewable energy and interconnection between power markets has brought with it challenges related to power balance and grid stability. Consumption and generation of electric power needs to be at balance at all times and a secure and reliable power system requires sensitivity to multiple time scales. Increased demand for balancing energy and ancillary services has the potential of making pump storage projects in Norway...

  14. Responsibilities to Plan for Ancillary Care Pose Ethical Challenges for Nutrition Research in the Community Setting12

    OpenAIRE

    Merritt, Maria W.; Taylor, Holly A.

    2012-01-01

    Investigators who conduct nutrition research in the community setting, particularly among underserved populations, face the ethical question of whether and how to respond to participants’ unmet health needs. The research ethics literature conceptualizes this question as one of ancillary care (AC): what is the nature and extent of researchers’ ethical responsibilities, if any, to provide or facilitate health care that research participants need but that is not necessary to ensure the safety or...

  15. Urban damage assessment using multimodal QuickBird images and ancillary data: the Bam and the Boumerdes earthquakes

    OpenAIRE

    Chesnel, Anne-Lise; Binet, Renaud; Wald, Lucien

    2008-01-01

    Remote sensing has proved its usefulness for the crisis mitigation through situation report and damage assessment. Visual analysis of satellite images is conducted by analysts, however automatic or decision aid method are desired. We propose a semi-automatic damage assessment method based on a pair of very high spatial resolution (VHR) images and some ancillary data. It is applied to two disaster cases, for which the QuickBird images acquisition conditions differ. For each case, the two image...

  16. Removal Action Work Plan for 105-DR and 105-F Building Interim Safe Storage Projects and Ancillary Buildings

    International Nuclear Information System (INIS)

    This document contains the removal action work plan for the 105-DR and 105-F Reactor buildings and ancillary facilities. These buildings and facilities are located in the 100-D/DR and 100-F Areas of the Hanford Site, which is owned and operated by the US Department of Energy (DOE), in Benton County, Washington. The 100 Areas (including the 100-D/DR and 100-F Areas) of the Hanford Site were placed on the US Environmental Protection Agency's (EPA's) National Priorities List under the ''Comprehensive Environmental Response, Compensation, and Liability Act of 1980'' (CERCLA). The DOE has determined that hazardous substances in the 105-DR and 105-F Reactor buildings and four ancillary facilities present a potential threat to human health or the environment. The DOE has also determined that a non-time critical removal action is warranted at these facilities. Alternatives for conducting a non-time critical removal action were evaluated in the ''Engineering Evaluation/Cost Analysis for the 105-DR and 105-F Reactor Facilities and Ancillary Facilities'' (DOE-RL 1998a). The engineering evaluation/cost analysis (EE/CA) resulted in the recommendation to decontaminate and demolish the contaminated reactor buildings (except for the reactor blocks) and the ancillary facilities and to construct a safe storage enclosure (SSE) over the reactor blocks. The recommendation was approved in an action memorandum (Ecology et al. 1998) signed by the Washington State Department of Ecology (Ecology), EPA, and DOE. The DOE is the agency responsible for implementing the removal actions in the 105-D/DR and 105-F Areas. Ecology is the lead regulatory agency for facilities in the 100-D/DR Area, and EPA is the lead regulatory agency for facilities in the 100-F Area. The term ''lead regulator agency'' hereinafter, refers to these authorities. This removal action work plan supports implementation of the non-time critical removal action

  17. Role of the Emp Pilus Subunits of Enterococcus faecium in Biofilm Formation, Adherence to Host Extracellular Matrix Components, and Experimental Infection.

    Science.gov (United States)

    Montealegre, Maria Camila; Singh, Kavindra V; Somarajan, Sudha R; Yadav, Puja; Chang, Chungyu; Spencer, Robert; Sillanpää, Jouko; Ton-That, Hung; Murray, Barbara E

    2016-05-01

    Enterococcus faecium is an important cause of hospital-associated infections, including urinary tract infections (UTIs), bacteremia, and infective endocarditis. Pili have been shown to play a role in the pathogenesis of Gram-positive bacteria, including E. faecium We previously demonstrated that a nonpiliated ΔempABC::cat derivative of E. faecium TX82 was attenuated in biofilm formation and in a UTI model. Here, we studied the contributions of the individual pilus subunits EmpA, EmpB, and EmpC to pilus architecture, biofilm formation, adherence to extracellular matrix (ECM) proteins, and infection. We identified EmpA as the tip of the pili and found that deletion of empA reduced biofilm formation to the same level as deletion of the empABC operon, a phenotype that was restored by reconstituting in situ the empA gene. Deletion of empB also caused a reduction in biofilm, while EmpC was found to be dispensable. Significant reductions in adherence to fibrinogen and collagen type I were observed with deletion of empA and empB, while deletion of empC had no adherence defect. Furthermore, we showed that each deletion mutant was significantly attenuated in comparison to the isogenic parental strain, TX82, in a mixed-inoculum UTI model (P infective endocarditis model (P = 0.0088). Our results indicate that EmpA and EmpB, but not EmpC, contribute to biofilm and adherence to ECM proteins; however, all the Emp pilins are important for E. faecium to cause infection in the urinary tract. PMID:26930703

  18. Recent Advances in Subunit Vaccine Carriers.

    Science.gov (United States)

    Vartak, Abhishek; Sucheck, Steven J

    2016-01-01

    The lower immunogenicity of synthetic subunit antigens, compared to live attenuated vaccines, is being addressed with improved vaccine carriers. Recent reports indicate that the physio-chemical properties of these carriers can be altered to achieve optimal antigen presentation, endosomal escape, particle bio-distribution, and cellular trafficking. The carriers can be modified with various antigens and ligands for dendritic cells targeting. They can also be modified with adjuvants, either covalently or entrapped in the matrix, to improve cellular and humoral immune responses against the antigen. As a result, these multi-functional carrier systems are being explored for use in active immunotherapy against cancer and infectious diseases. Advancing technology, improved analytical methods, and use of computational methodology have also contributed to the development of subunit vaccine carriers. This review details recent breakthroughs in the design of nano-particulate vaccine carriers, including liposomes, polymeric nanoparticles, and inorganic nanoparticles. PMID:27104575

  19. Map of risks for the implementation of radio-frequency identification: application of ancillaries in the University Hospital Jean Verdier.

    Science.gov (United States)

    Bertrand, E; Schlatter, J

    2010-01-01

    Ancillaries are surgical instruments, such as orthopedical instruments set for reconstruction of knee (a mounting arm...) used to implant or extract prosthesis. Their management involves the departments of sterilization and surgery as well as the suppliers. Such a long circuit exposes the instruments to potential risk hazards like a lack of traceability as the suspicion of Creutzfeldt-Jakob. In order to reduce the risk of errors we will propose the implementation of radio-frequency identification (RFID) to trace the ancillaries during each step of the supply chain. The objective of our study is to analyze and to map the risks associated with RFID implementation. A preliminary analysis of risks (APR) is conducted to map out the hazards for the implementation of RFID. The APR identifies 162 scenarios with a maximum risk connected to environment and technology. To reduce the risks identified, 22 courses of action are proposed, such as audits, training, and internal controls. For each action, a procedure has been designed and evaluated. This preliminary analysis of risks allows targeting the potential dangers for the RFID implementation applied to ancillaries and reduces them significantly. PMID:20187581

  20. MspA Nanopores from Subunit Dimers

    OpenAIRE

    Pavlenok, Mikhail; Derrington, Ian M.; Gundlach, Jens H.; Niederweis, Michael

    2012-01-01

    Mycobacterium smegmatis porin A (MspA) forms an octameric channel and represents the founding member of a new family of pore proteins. Control of subunit stoichiometry is important to tailor MspA for nanotechnological applications. In this study, two MspA monomers were connected by linkers ranging from 17 to 62 amino acids in length. The oligomeric pore proteins were purified from M. smegmatis and were shown to form functional channels in lipid bilayer experiments. These results indicated tha...

  1. Expression of Telomerase Subunits in Gastric Cancer

    Institute of Scientific and Technical Information of China (English)

    CHEN Fenghua; HU Lihua; LI Yirong; WANG Lin

    2005-01-01

    To detect the expression of telomerase subunits human telomerase reverse transcriptase, human telomerase associated protein 1 and human telomerase RNA) in gastric cancer and to examine the role that different telomerase subunits play in the gastric carcinogenesis, reverse transcription-polymerase chain reaction (RT-PCR) was used to detect telomerase subunits messenger RNA in 24 samples of gastric cancer and corresponding non-cancerous tissue. The results showed that the positive rate of hTERT mRNA from gastric cancer and corresponding non-cancerous tissues was 100 % and 25 %, respectively. The former was significantly higher than the latter (χ2 =26.4, P<0.01). The positive rate of hTEP1 mRNA from gastric cancer and corresponding non-cancerous tissues was 100 % and 91.7 %, respectively and no significant difference was found between them (χ2 =2.1, P>0.05). The positive rates of hTR for gastric cancer and corresponding non-cancerous tissues were both 100 % and no significant difference existed between them. It is concluded that in contrast to hTEP1 and hTR, the up-regulation of hTERT mRNA expression may play a more important role in the development of gastric cancer.

  2. Na+ channel β subunits: Overachievers of the ion channel family

    OpenAIRE

    LoriLIsom; WilliamJBrackenbury

    2011-01-01

    Voltage gated Na+ channels (VGSCs) in mammals contain a pore-forming α subunit and one or more β subunits. There are five mammalian β subunits in total: β1, β1B, β2, β3, and β4, encoded by four genes: SCN1B-SCN4B. With the exception of the SCN1B splice variant, β1B, the β subunits are type I topology transmembrane proteins. In contrast, β1B lacks a transmembrane domain and is a secreted protein. A growing body of work shows that VGSC β subunits are multifunctional. While they do not form the...

  3. Ruthenium(II) polypyridyl complexes with hydrophobic ancillary ligand as Aβ aggregation inhibitors.

    Science.gov (United States)

    Vyas, Nilima A; Ramteke, Shefali N; Kumbhar, Avinash S; Kulkarni, Prasad P; Jani, Vinod; Sonawane, Uddhavesh B; Joshi, Rajendra R; Joshi, Bimba; Erxleben, Andrea

    2016-10-01

    The synthesis, spectral and electrochemical characterization of the complexes of the type [Ru(NN)2(txbg)](2+) where NN is 2,2'-bipyridine (bpy) (1), 1,10-phenanthroline (phen) (2), dipyrido [3,2-d:2',3f] quinoxaline (dpq) (3), and dipyrido[3,2-a:2',3'-c]phenazine (dppz) (4) which incorporate the tetra-xylene bipyridine glycoluril (txbg) as the ancillary ligand are described in detail. Crystal structures of ligand txbg and complex 2 were solved by single crystal X-ray diffraction. Thioflavin T (ThT) fluorescence and Transmission Electron Microscopy (TEM) results indicated that at micromolar concentration all complexes exhibit significant potential of Aβ aggregation inhibition, while the ligand txbg displayed weak activity towards Aβ aggregation. Complex 1 showed relatively low inhibition (70%) while complexes 2-4 inhibited nearly 100% Aβ aggregation after 240 h of incubation. The similar potential of complexes 2-4 and absence of any trend in their activity with the planarity of polypyridyl ligands suggests there is no marked effect of planarity of coligands on their inhibitory potential. Further studies on acetylcholinesterase (AChE) inhibition indicated very weak activity of these complexes against AChE. Detailed interactions of Aβ with both ligand and complex 2 have been studied by molecular modeling. Complex 2 showed interactions involving all three polypyridyl ligands with hydrophobic region of Aβ. Furthermore, the toxicity of these complexes towards human neuroblastoma cells was evaluated by MTT assay and except complex 4, the complexes displayed very low toxicity. PMID:27406812

  4. Initial Sr-isotope, dating and ancillary geochemical studies on kimberlite and associated inclusions

    International Nuclear Information System (INIS)

    The feasibility of dating the time of pipe intrusions by the Rb-Sr method was first considered. However, the main objective was to investigate the limitations imposed by Sr isotopic evidence (and ancillary elemental abundance data) on the nature and genesis of kimberlite. Measurements, mainly by mass spectroscopy, of K, Rb and Sr isotopic ratios were made on kimberlite whole rocks (16 samples), peridotite and eclogite nodules (12 samples), mineral concentrates from the above rock types, and phlogopite and diopside nodules (94 mica and other separates, mainly clinopyroxenes), pipe wall rocks (6 whole rocks and 5 separated muscovites) and ground waters (6 samples). Studies on phlogopite micas which occur in kimberlite groundmass and associated peridotite and eclogite inclusions suggest that valid ages for pipe emplacement may be obtained by the Rb-Sr isochron method. Phlogopite nodule samples give anomalous results due to radiogenic Sr retention. Results for the following pipes are reported: Wesselton, Du Toitspan, De Beers, Bultfontein and Monastery (mean age 86 plus minus 3 m.y.); Roberts Victor (127 plus minus 3 m.y., possibly less reliable); Swartruggens (147 plus minus 4 m.y.); Gross Brukkaros (84 m.y. - not considered reliable); Lashaine Volcano, Tanzania (270 m.y. - tentative, pre-emplacement date). Certain samples cannot be used for dating: nodular whole rocks and garnets because they are contaminated; kimberlite and clinopyroxenes because they are insufficiently enriched in radiogenic Sr. The granite-gneiss basement wall-rock of the Kimberley pipes has an age of 2 900 m.y. An interesting outcome of the age work is the postulated existence of phlogopite calcite in the mantle. Incomplete (partial) Sr-isotopic equilibration probably occured between constituent minerals

  5. MspA nanopores from subunit dimers.

    Directory of Open Access Journals (Sweden)

    Mikhail Pavlenok

    Full Text Available Mycobacterium smegmatis porin A (MspA forms an octameric channel and represents the founding member of a new family of pore proteins. Control of subunit stoichiometry is important to tailor MspA for nanotechnological applications. In this study, two MspA monomers were connected by linkers ranging from 17 to 62 amino acids in length. The oligomeric pore proteins were purified from M. smegmatis and were shown to form functional channels in lipid bilayer experiments. These results indicated that the peptide linkers did not prohibit correct folding and localization of MspA. However, expression levels were reduced by 10-fold compared to wild-type MspA. MspA is ideal for nanopore sequencing due to its unique pore geometry and its robustness. To assess the usefulness of MspA made from dimeric subunits for DNA sequencing, we linked two M1-MspA monomers, whose constriction zones were modified to enable DNA translocation. Lipid bilayer experiments demonstrated that this construct also formed functional channels. Voltage gating of MspA pores made from M1 monomers and M1-M1 dimers was identical indicating similar structural and dynamic channel properties. Glucose uptake in M. smegmatis cells lacking porins was restored by expressing the dimeric mspA M1 gene indicating correct folding and localization of M1-M1 pores in their native membrane. Single-stranded DNA hairpins produced identical ionic current blockades in pores made from monomers and subunit dimers demonstrating that M1-M1 pores are suitable for DNA sequencing. This study provides the proof of principle that production of single-chain MspA pores in M. smegmatis is feasible and paves the way for generating MspA pores with altered stoichiometries. Subunit dimers enable better control of the chemical and physical properties of the constriction zone of MspA. This approach will be valuable both in understanding transport across the outer membrane in mycobacteria and in tailoring MspA for nanopore

  6. MspA nanopores from subunit dimers.

    Science.gov (United States)

    Pavlenok, Mikhail; Derrington, Ian M; Gundlach, Jens H; Niederweis, Michael

    2012-01-01

    Mycobacterium smegmatis porin A (MspA) forms an octameric channel and represents the founding member of a new family of pore proteins. Control of subunit stoichiometry is important to tailor MspA for nanotechnological applications. In this study, two MspA monomers were connected by linkers ranging from 17 to 62 amino acids in length. The oligomeric pore proteins were purified from M. smegmatis and were shown to form functional channels in lipid bilayer experiments. These results indicated that the peptide linkers did not prohibit correct folding and localization of MspA. However, expression levels were reduced by 10-fold compared to wild-type MspA. MspA is ideal for nanopore sequencing due to its unique pore geometry and its robustness. To assess the usefulness of MspA made from dimeric subunits for DNA sequencing, we linked two M1-MspA monomers, whose constriction zones were modified to enable DNA translocation. Lipid bilayer experiments demonstrated that this construct also formed functional channels. Voltage gating of MspA pores made from M1 monomers and M1-M1 dimers was identical indicating similar structural and dynamic channel properties. Glucose uptake in M. smegmatis cells lacking porins was restored by expressing the dimeric mspA M1 gene indicating correct folding and localization of M1-M1 pores in their native membrane. Single-stranded DNA hairpins produced identical ionic current blockades in pores made from monomers and subunit dimers demonstrating that M1-M1 pores are suitable for DNA sequencing. This study provides the proof of principle that production of single-chain MspA pores in M. smegmatis is feasible and paves the way for generating MspA pores with altered stoichiometries. Subunit dimers enable better control of the chemical and physical properties of the constriction zone of MspA. This approach will be valuable both in understanding transport across the outer membrane in mycobacteria and in tailoring MspA for nanopore sequencing of DNA. PMID

  7. Hypersecretion of the alpha-subunit in clinically non-functioning pituitary adenomas: Diagnostic accuracy is improved by adding alpha-subunit/gonadotropin ratio to levels of alpha-subunit

    DEFF Research Database (Denmark)

    Andersen, Marianne; Ganc-Petersen, Joanna; Jørgensen, Jens O L;

    2010-01-01

    In vitro, the majority of clinically non-functioning pituitary adenomas (NFPAs) produce gonadotropins or their alpha-subunit; however, in vivo, measurements of alpha-subunit levels may not accurately detect the hypersecretion of the alpha-subunit.......In vitro, the majority of clinically non-functioning pituitary adenomas (NFPAs) produce gonadotropins or their alpha-subunit; however, in vivo, measurements of alpha-subunit levels may not accurately detect the hypersecretion of the alpha-subunit....

  8. Impact of Market Behavior, Fleet Composition, and Ancillary Services on Revenue Sufficiency

    Energy Technology Data Exchange (ETDEWEB)

    Frew, Bethany [National Renewable Energy Lab. (NREL), Golden, CO (United States); Gallo, Giulia [National Renewable Energy Lab. (NREL), Golden, CO (United States); Brinkman, Gregory [National Renewable Energy Lab. (NREL), Golden, CO (United States); Milligan, Michael [National Renewable Energy Lab. (NREL), Golden, CO (United States); Clark, Kara [National Renewable Energy Lab. (NREL), Golden, CO (United States); Bloom, Aaron [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-06-01

    Revenue insufficiency, or the missing money problem, occurs when the revenues that generators earn from the market are not sufficient to cover both fixed and variable costs to remain in the market and/or justify investments in new capacity, which may be needed for reliability. The near-zero marginal cost of variable renewable generators further exacerbates these revenue challenges. Estimating the extent of the missing money problem in current electricity markets is an important, nontrivial task that requires representing both how the power system operates and how market participants behave. This paper explores the missing money problem using a production cost model that represented a simplified version of the Electric Reliability Council of Texas (ERCOT) energy-only market for the years 2012-2014. We evaluate how various market structures -- including market behavior, ancillary services, and changing fleet compositions -- affect net revenues in this ERCOT-like system. In most production cost modeling exercises, resources are assumed to offer their marginal capabilities at marginal costs. Although this assumption is reasonable for feasibility studies and long-term planning, it does not adequately consider the market behaviors that impact revenue sufficiency. In this work, we simulate a limited set of market participant strategic bidding behaviors by means of different sets of markups; these markups are applied to the true production costs of all gas generators, which are the most prominent generators in ERCOT. Results show that markups can help generators increase their net revenues overall, although net revenues may increase or decrease depending on the technology and the year under study. Results also confirm that conventional, variable-cost-based production cost simulations do not capture prices accurately, and this particular feature calls for proxies for strategic behaviors (e.g., markups) and more accurate representations of how electricity markets work. The

  9. Localisation of main and ancillary foramina within the mesial and distal roots of the first lower molars

    Directory of Open Access Journals (Sweden)

    Jovanović-Medojević Milica

    2005-01-01

    Full Text Available Introduction. Understanding the morphology of the root canal system, and especially its apical third, represents the basic precondition for the successful treatment of diseased pulp and the apical endodontium. Aim. The aim of this study was to precisely locate the main and ancillary foramina in the mesial and distal first lower molars. Method. One hundred extracted first lower molars, originating from persons of both sexes and three different age groups, were used in the study. Results. The analysis of the sampled molars’ apical third was carried out using a binocular magnifier and a digital X-ray scanner (Trophy. The results showed that the main mesial and distal root foramina were located mostly on the distal surface. The ancillary mesial and distal root foramina were located at the lingual end, in most cases. Statistical analysis demonstrated the congruence of results achieved using the binocular magnifier and digital x-ray in 100% of cases if the main foramen is located on the very top of the mesial root (χ2 =17.23; p<0.001, and in 92.9% of cases if the main foramen is localised on the very top of the distal root of the first lower molar (χ2 =12.07; p<0.001. Conclusion. The most common localisation of the main foramina for all age categories and in both mesial and distal roots is on the distal surface of the root. The greatest number of ancillary foramina was observed in the youngest age category, while they were localised most often on the lingual side of the mesial and distal root.

  10. Advances in the Research of AMPK and its Subunit Genes

    Directory of Open Access Journals (Sweden)

    R.S. Jiang

    2013-01-01

    Full Text Available AMP-activated kinase (AMPK is a heterotrimeric complex composed of three subunits and is the core energy sensor of the cell. The AMPK activity is important for survival during periods of stress and starvation and also has implications in type II diabetes, obesity, metabolic syndrome, longevity and cancer, etc. The activation of AMPK is triggered through binding of Adenosine Monophosphate Activated Proteins (AMP to the Bateman domains of the gamma subunit, leading to increased phosphorylation of the threonine 172 on the alpha subunit by inducing allosteric activation and inhibiting dephosphorylation. AMPK and its subunits have been the focuses of many researchers dealing with genetic and metabolic issues. The study makes a comprehensive review on the structure, function, distribution, enzyme activity, the genetic mutation and other aspects of AMPK and its subunit genes, with the aim to outline main aspects of present researches on AMPK and its subunits in animal genetics.

  11. Comparative Analysis of Eubacterial DNA Polymerase Ⅲ Alpha Subunits

    Institute of Scientific and Technical Information of China (English)

    Xiao-Qian Zhao; Jian-Fei Hu; Jun Yu

    2006-01-01

    DNA polymerase Ⅲ is one of the five eubacterial DNA polymerases that is responsible for the replication of DNA duplex. Among the ten subunits of the DNA polymerase Ⅲ core enzyme, the alpha subunit catalyzes the reaction for polymerizing both DNA strands. In this study, we extracted genomic sequences of the alpha subunit from 159 sequenced eubacterial genomes, and carried out sequencebased phylogenetic and structural analyses. We found that all eubacterial genomes have one or more alpha subunits, which form either homodimers or heterodimers.Phylogenetic and domain structural analyses as well as copy number variations of the alpha subunit in each bacterium indicate the classification of alpha subunit into four basic groups: polC, dnaE1, dnaE2, and dnaE3. This classification is of essence in genome composition analysis. We also consolidated the naming convention to avoid further confusion in gene annotations.

  12. Strategies for carbon dioxide emissions reductions: Residential natural gas efficiency, economic, and ancillary health impacts in Maryland

    International Nuclear Information System (INIS)

    As part of its commitments to the Regional Greenhouse Gas Initiative (RGGI), the State of Maryland, USA, auctions emission permits to electric utilities, creating revenue that can be used to benefit consumers and the environment. This paper explores the CO2 emissions reductions that may be possible by allocating some of that revenue to foster efficiency improvements in the residential sector's use of natural gas. Since these improvements will require changes to the capital stock of houses and end use equipment, efficiency improvements may be accompanied by economic and ancillary health impacts, both of which are quantified in this paper.

  13. Design of OsII-based Sensitizers for Dye-Sensitized Solar Cells:Influence of Heterocyclic Ancillaries

    OpenAIRE

    Hu, Fa-chun; Wang, Sheng-Wei; Planells, Miquel; Robertson, Neil; Padhy, Harihara; Du, Bo-sian; Chi, Yun; Yang, Po-fan; Lin, Hao-Wu; Lee, Gene-Hsiang; Chou, Pi-Tai

    2013-01-01

    A series of OsII sensitizers (TFOS-x, in which x=1, 2, or 3) with a single 4,4′-dicarboxy-2,2′-dipyridine (H2dcbpy) anchor and two chelating 2-pyridyl (or 2-pyrimidyl) triazolate ancillaries was successfully prepared. Single-crystal X-ray structural analysis showed that the core geometry of the OsII-based sensitizers consisted of one H2dcbpy unit and two eclipsed cis-triazolate fragments; this was notably different from the RuII-based counterparts, in which the azolate (both pyrazolate and tr...

  14. From a bundled energy-capacity pricing model to an energy-capacity-ancillary services pricing model

    International Nuclear Information System (INIS)

    In this paper, we extend the Chilean power generation pricing mechanism, with capacity and energy payments, to one where ancillary services (AS), as frequency regulation and voltage control, are explicitly recognized. Adequacy and security attributes of the electric system and the public good characteristics of AS are set within the payment structure to distribute the financing of AS among those who benefit from their provision. The contribution to finance the provision of AS is determined assessing the value assigned to the system security by each agent, following what's an efficient pricing mechanism in the presence of public goods

  15. Autocatalytic Processing of m-AAA Protease Subunits in Mitochondria

    OpenAIRE

    Koppen, Mirko; Bonn, Florian; Ehses, Sarah; Langer, Thomas

    2009-01-01

    m-AAA proteases are ATP-dependent proteolytic machines in the inner membrane of mitochondria which are crucial for the maintenance of mitochondrial activities. Conserved nuclear-encoded subunits, termed paraplegin, Afg3l1, and Afg3l2, form various isoenzymes differing in their subunit composition in mammalian mitochondria. Mutations in different m-AAA protease subunits are associated with distinct neuronal disorders in human. However, the biogenesis of m-AAA protease complexes or of individua...

  16. Secure provision of reactive power ancillary services in competitive electricity markets

    Science.gov (United States)

    El-Samahy, Ismael

    decoupled and assumed to be fixed during the reactive power dispatch procedures; however, the effect of reactive power on real power is considered in the model by calculating the required reduction in real power output of a generator due to an increase in its reactive power supply. In this case, real power generation is allowed to be rescheduled, within given limits, from the already dispatched levels obtained from the energy market clearing process. The proposed dispatch model achieves the main objective of an ISO in a competitive electricity market, which is to provide the required reactive power support from generators at least cost while ensuring a secure operation of the power system. The proposed reactive power procurement and dispatch models capture both the technical and economic aspects of power system operation in competitive electricity markets; however, from an optimization point of view, these models represent non-convex mixed integer non-linear programming (MINLP) problems due to the presence of binary variables associated with the different regions of reactive power operation in a synchronous generator. Such MINLP optimization problems are difficult to solve, especially for an actual power system. A novel Generator Reactive Power Classification (GRPC) algorithm is proposed in this thesis to address this issue, with the advantage of iteratively solving the optimization models as a series of non-linear programming (NLP) sub-problems. The proposed reactive power procurement and dispatch models are implemented and tested on the CIGRE 32-bus system, with several case studies that represent different practical operating scenarios. The developed models are also compared with other approaches for reactive power provision, and the results demonstrate the robustness and effectiveness of the proposed model. The results clearly reveal the main features of the proposed models for optimal provision of reactive power ancillary service, in order to suit the requirements of

  17. Test blanket module maintenance operations between port plug and ancillary equipment unit in ITER

    International Nuclear Information System (INIS)

    In collaboration between the FZK and KFKI-RMKI, in the frame of the activities of the EU Breeder Blanket Programme a concept for test blanket module (TBM) integration, maintenance schedules and all required special purpose equipments has been developed. During the first 10 years of ITER operation four different plasma scenarios will be used. Hence it will be possible to investigate the characteristics (e.g. tritium breeding performance) of different TBM concepts which will be installed during operation for the different phases of ITER operation in the equatorial ports 2, 16 and 18. In every port two TBMs will be accommodated, in the port 16 will be the European helium-cooled pebble bed blanket. In different phases of ITER operation different TBMs will be used. Therefore a complex maintenance process is necessary for the exchange of TBMs. Two TBMs are mounted onto one common frame, into a port plug (PP), which offers a standardised interface to the vacuum vessel (VV). It is cantilevered with a flange to VV port extension. This attachment system is the same in every equatorial port, so the exchange process of this structure with the TBMs is also the standard operation of ITER. Several components of the helium cooling system of the EU breeder modules, valves, pipes, gas mixers, thermal sleeves, pipes for tritium extraction, measurement system are integrated into the ancillary equipment unit (AEU), which during the operation will connect the port plug to the subsystems. The bigger part of the AEU is accommodated in the port cell and the rest part of it is penetrated into the interspace inside the bioshield and reach the back plane of the installed PP. The remote handling operations for connection/disconnection of an interface between the PP of the EU-TBMs and the AEU are investigated with the goal to reach a quick and simple TBM exchange procedure. The current design of the EU-TBMs foresees up to 18 supply lines for both TBMs. These lines have to be connected here. A

  18. Test blanket module maintenance operations between port plug and ancillary equipment unit in ITER

    International Nuclear Information System (INIS)

    In collaboration between the FZK and KFKI-RMKI, in the frame of the activities of the EU Breeder Blanket Programme a concept for Test Blanket Module (TBM) integration, maintenance schedules and all required special purpose equipments has been developed. During the first 10 years of ITER operation 4 different plasma scenarios will be used. Hence it will be possible to investigate the characteristics (e.g. tritium breeding performance) of different TBM concepts which will be installed during operation for the different phases of ITER operation in the equatorial ports 2, 16 and 18. In every port will be two TBMs accomodated, in the port 16 will be the the European Helium Cooled Pebble Bed blanket. In the different phases of ITER operation different TBMs will be used. Therefore a complex maintenance process is necessary for exchange the TBMs. Two TBMs are mounted into one common frame, into a Port Plug (PP), which offers a standardised interface to the Vacuum Vessel (VV). It is cantilevered with a flange to VV Port Extension. This attachment system is the same in every equatorial port, so the exchange process of this structure with the TBMs are also standard operation of ITER. Several components of the Helium cooling system of the EU breeder modules, valves, pipes, gas mixers, thermal sleeves, pipes for tritium extraction, measurement system, etc. All of them is integrated into the Ancillary Equipment Unit (AEU) which during operation will connect the port plug to the sub systems. The bigger part of the AEU is accomodated in the Port Cell and the rest part of it is penetrate to the interspace inside the bioshield and reach the back plane of the installed PP. The remote handling operations for connection / disconnection of an interface between the PP of the EU-TBMs and the AEU are investigated with the goal to reach a quick and simple TBM exchange procedure. The current design of the EU-TBMs foresees up to 18 supply lines for both TBMs. These lines have to be connected

  19. Designability of protein subunits on a lattice

    Science.gov (United States)

    Dmitry, Green; Wingreen, Ned; Tang, Chao; Miller, Jonathan

    2001-03-01

    Native protein folds are often made up of distinct sub folds. We use a two-dimensional lattice protein model based on hydrophobicity to study this feature. The "designability" of a structure is defined as the number of sequences with that structure as their unique, lowest energy configuration. A "highly designable" structure is one that is encoded by a disproportionate share of sequences. The designability of a structure encapsulates the insensitivity to mutation of the sequences that fold into it. We consider structures on a 6x6 and an 8x8 lattice that are composed of two loops, and find that their designability is correlated with the designability of the component loops. This result points to a more general principle asserting that some proteins may be built up from highly designable subunits.

  20. On combining multi-normalization and ancillary measures for the optimal score level fusion of fingerprint and voice biometrics

    Science.gov (United States)

    Mohammed Anzar, Sharafudeen Thaha; Sathidevi, Puthumangalathu Savithri

    2014-12-01

    In this paper, we have considered the utility of multi-normalization and ancillary measures, for the optimal score level fusion of fingerprint and voice biometrics. An efficient matching score preprocessing technique based on multi-normalization is employed for improving the performance of the multimodal system, under various noise conditions. Ancillary measures derived from the feature space and the score space are used in addition to the matching score vectors, for weighing the modalities, based on their relative degradation. Reliability (dispersion) and the separability (inter-/intra-class distance and d-prime statistics) measures under various noise conditions are estimated from the individual modalities, during the training/validation stage. The `best integration weights' are then computed by algebraically combining these measures using the weighted sum rule. The computed integration weights are then optimized against the recognition accuracy using techniques such as grid search, genetic algorithm and particle swarm optimization. The experimental results show that, the proposed biometric solution leads to considerable improvement in the recognition performance even under low signal-to-noise ratio (SNR) conditions and reduces the false acceptance rate (FAR) and false rejection rate (FRR), making the system useful for security as well as forensic applications.

  1. A framework for cost-based pricing of transmission and ancillary services in competitive electric power markets

    International Nuclear Information System (INIS)

    In this paper the authors propose a framework for accurate cost determination and pricing of transmission and ancillary services in competitive electric power markets. The proposed framework is based on their anticipation of the evolving environment and industry structure. They envision the future as a competitive energy market with a centralized control entity that coordinates system activities, prices transmission and ancillary services and controls various system resources. This control entity has control over a certain (pre-defined) geographical area. It is proposed that the system operation and control be kept as they are currently done in control centers, no major change in these functions is required for the proposed pricing strategy. The pricing strategy is divided into two main classes based on time scale separation and firmness, short and long term, firm and interruptible contracts. The approach is based on superposition of different transaction on the network, and a three-part tariff design. The charges are directly related to the impact of each transaction on the system

  2. Mitigation costs, distributional effects, and ancillary benefits of carbon policies in the Nordic countries, the U.K., and Ireland

    Energy Technology Data Exchange (ETDEWEB)

    Bye, B; Rosendahl, K.E. [Research Department, Statistics Norway, P.O. Box 8131 Dep., 0033 Oslo (Norway); Kverndokk, S. [Ragnar Frisch Centre for Economic Research, Gaustadalleen 21, 0349 Oslo (Norway)

    2002-07-01

    This paper provides a survey of top-down modelling analyses of carbon (C) abatement mitigation costs, distributional effects and ancillary benefits in the Nordic countries, the U.K. and Ireland. Special emphasis is placed on the effects of revenue recycling and tax exemptions. According to the analyses, modest emissions reductions can be met without substantial costs for the countries studied, and a strong double dividend is found in some analyses. The gross domestic product (GDP) or welfare effects are mostly in the range of -0.4 and 1.2% when C emissions are reduced by 20-30 per cent. Lowest costs are obtained without tax exemptions and with tax revenues used to reduce distortionary taxes. Ancillary benefits are mostly in the range 35-80/MgC{sup -1}, i.e., about the same order of magnitude as the mitigation costs. Distributional effects are mostly regressive, unless the tax revenues are distributed in lump-sum fashion with equal transfers to each household.

  3. Active Power Control of Wind Turbines for Ancillary Services: A Comparison of Pitch and Torque Control Methodologies

    Energy Technology Data Exchange (ETDEWEB)

    Aho, Jacob; Fleming, Paul; Pao, Lucy Y.

    2016-08-01

    As wind energy generation becomes more prevalent in some regions, there is increased demand for wind power plants to provide ancillary services, which are essential for grid reliability. This paper compares two different wind turbine control methodologies to provide active power control (APC) ancillary services, which include derating or curtailing power generation, providing automatic generation control (AGC), and providing primary frequency control (PFC). The torque APC controller provides all power control through the power electronics whereas the pitch APC controller uses the blade pitch actuators as the primary means of power control. These controllers are simulated under various wind conditions with different derating set points and AGC participation levels. The metrics used to compare their performance are the damage equivalent loads (DELs) induced on the structural components and AGC performance metrics, which are used to determine the payments for AGC services by system operators in the United States. The simulation results show that derating the turbine reduces structural loads for both control methods, with the APC pitch control providing larger reductions in DELs, lower AGC performance scores, and higher root-mean-square pitch rates. Providing AGC increases the structural loads when compared to only derating the turbine, but even the AGC DELs are generally lower than those of the baseline control system. The torque APC control methodology also allows for more sustained PFC responses under certain derating conditions.

  4. The Schizosaccharomyces pombe casein kinase II alpha and beta subunits: evolutionary conservation and positive role of the beta subunit.

    OpenAIRE

    Roussou, I; Draetta, G

    1994-01-01

    Casein kinase II is a key regulatory enzyme involved in many cellular processes, including the control of growth and cell division. We report the molecular cloning and sequencing of cDNAs encoding the alpha and the beta subunits of casein kinase II of Schizosaccharomyces pombe. The deduced amino acid sequence of Cka1, the alpha catalytic subunit, shows high sequence similarity to alpha subunits identified in other species. The amino acid sequence of Ckb1, the S. pombe beta subunit, is 57% ide...

  5. Subunit structure of the follitropin receptor

    International Nuclear Information System (INIS)

    Both of the α and β subunits of intact human follitropin (FSH) were radioiodinated with 125I-FSH-sodium iodide and chloramine-T, and could be resolved on polyacrylamide gels (SDS-PAGE). The electrophoretic mobility of radioiodinated FSH α and β subunits as well as the αβ dimer changed markedly depending on the concentration of reducing agents. 125I-FSH (Ka = 1.4 x 1010 M-1), complexes to the receptor on procine granulosa cells or in Triton X-100 extracts, was affinity-crosslinked with a cleavable (nondisulfide) homobifunctional reagent, bis[2-(succinimidooxycarbonyloxy)ethyl]sulfone, solubilized in sodium dodecyl sulfate with or without reducing agents, and electrophoresed. Crosslinked samples revealed three additional bands of slower electrophoretic mobility, corresponding to 65 (unreduced 62), 83 (unreduced 76) and 117 (unreduced 110)kDa, in addition to hormone bands. Formation of the three bands requires the 125I-FSH hormone to bind specifically to the receptor with subsequent cross-linking. The rate of formation and cleavage of the cross-linked complexes indicated a sequential and incremental addition of 22, 18, and 34 kDa components to the FSH αβ dimer. The results of reduction of cross-linked complexes demonstrated the existence of disulfide linkage between the three components. FSH was photoactively derivatized with N-hydroxysuccinimide ester of 4-azidobenzolyl-glycine and radioiodinated for photoaffinity labeling. When derivatized 125I-FSH (Ka = 1.12 1010 M-1) bound to the cell was photolyzed for cross-linking and resolved on the SDS-PAGE, two new bands (106 and 61 kDa) under reducing condition appeared in addition to the hormone bands. Upon reduction with dithiotheitol and second-dimensional electrophoresis, the unreduced 104 kDa (reduced 106 kDa) band released two small components 31 and 14 kDa

  6. Dynamic regulation of β1 subunit trafficking controls vascular contractility

    Science.gov (United States)

    Leo, M. Dennis; Bannister, John P.; Narayanan, Damodaran; Nair, Anitha; Grubbs, Jordan E.; Gabrick, Kyle S.; Boop, Frederick A.; Jaggar, Jonathan H.

    2014-01-01

    Ion channels composed of pore-forming and auxiliary subunits control physiological functions in virtually all cell types. A conventional view is that channels assemble with their auxiliary subunits before anterograde plasma membrane trafficking of the protein complex. Whether the multisubunit composition of surface channels is fixed following protein synthesis or flexible and open to acute and, potentially, rapid modulation to control activity and cellular excitability is unclear. Arterial smooth muscle cells (myocytes) express large-conductance Ca2+-activated potassium (BK) channel α and auxiliary β1 subunits that are functionally significant modulators of arterial contractility. Here, we show that native BKα subunits are primarily (∼95%) plasma membrane-localized in human and rat arterial myocytes. In contrast, only a small fraction (∼10%) of total β1 subunits are located at the cell surface. Immunofluorescence resonance energy transfer microscopy demonstrated that intracellular β1 subunits are stored within Rab11A-postive recycling endosomes. Nitric oxide (NO), acting via cGMP-dependent protein kinase, and cAMP-dependent pathways stimulated rapid (≤1 min) anterograde trafficking of β1 subunit-containing recycling endosomes, which increased surface β1 almost threefold. These β1 subunits associated with surface-resident BKα proteins, elevating channel Ca2+ sensitivity and activity. Our data also show that rapid β1 subunit anterograde trafficking is the primary mechanism by which NO activates myocyte BK channels and induces vasodilation. In summary, we show that rapid β1 subunit surface trafficking controls functional BK channel activity in arterial myocytes and vascular contractility. Conceivably, regulated auxiliary subunit trafficking may control ion channel activity in a wide variety of cell types. PMID:24464482

  7. Liposome-Based Adjuvants for Subunit Vaccines: Formulation Strategies for Subunit Antigens and Immunostimulators

    Directory of Open Access Journals (Sweden)

    Signe Tandrup Schmidt

    2016-03-01

    Full Text Available The development of subunit vaccines has become very attractive in recent years due to their superior safety profiles as compared to traditional vaccines based on live attenuated or whole inactivated pathogens, and there is an unmet medical need for improved vaccines and vaccines against pathogens for which no effective vaccines exist. The subunit vaccine technology exploits pathogen subunits as antigens, e.g., recombinant proteins or synthetic peptides, allowing for highly specific immune responses against the pathogens. However, such antigens are usually not sufficiently immunogenic to induce protective immunity, and they are often combined with adjuvants to ensure robust immune responses. Adjuvants are capable of enhancing and/or modulating immune responses by exposing antigens to antigen-presenting cells (APCs concomitantly with conferring immune activation signals. Few adjuvant systems have been licensed for use in human vaccines, and they mainly stimulate humoral immunity. Thus, there is an unmet demand for the development of safe and efficient adjuvant systems that can also stimulate cell-mediated immunity (CMI. Adjuvants constitute a heterogeneous group of compounds, which can broadly be classified into delivery systems or immunostimulators. Liposomes are versatile delivery systems for antigens, and they can carefully be customized towards desired immune profiles by combining them with immunostimulators and optimizing their composition, physicochemical properties and antigen-loading mode. Immunostimulators represent highly diverse classes of molecules, e.g., lipids, nucleic acids, proteins and peptides, and they are ligands for pattern-recognition receptors (PRRs, which are differentially expressed on APC subsets. Different formulation strategies might thus be required for incorporation of immunostimulators and antigens, respectively, into liposomes, and the choice of immunostimulator should ideally be based on knowledge regarding the

  8. Proteopedia Entry: The Large Ribosomal Subunit of "Haloarcula Marismortui"

    Science.gov (United States)

    Decatur, Wayne A.

    2010-01-01

    This article presents a "Proteopedia" page that shows the refined version of the structure of the "Haloarcula" large ribosomal subunit as solved by the laboratories of Thomas Steitz and Peter Moore. The landmark structure is of great impact as it is the first atomic-resolution structure of the highly conserved ribosomal subunit which harbors…

  9. Regulation of Glutamate Receptors by Their Auxiliary Subunits

    OpenAIRE

    Tomita, Susumu

    2010-01-01

    Glutamate receptors are major excitatory receptors in the brain. Recent findings have established auxiliary subunits of glutamate receptors as critical modulators of synaptic transmission, synaptic plasticity and neurological disorder. The elucidation of the molecular rules governing glutamate receptors and subunits will improve our understanding of synapses and of neural-circuit regulation in the brain.

  10. Identification of a novel HMW glutenin subunit and comparison of its amino acid sequence with those of homologous subunits

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Aegilops tauschii is the donor of the D genome of common wheat (Triticum aestivum). Genetic variation of HMW glutenin subunits encoded by the Glu-1Dt locus of Ae. tauschii has been found to be higher than that specified by the Glu-1D locus in common wheat. In the present note, we report the identification of a novel HMW glutenin subunit, Dy13t, from Ae. tauschii. The newly identified subunit possessed an electrophoretic mobility that was faster than that of the Dy12 subunit of common wheat. The complete ORF of encoding the Dy13t subunit contained 624 codons (excluding the stop codons). The amino acid sequence deduced from the Dy13t gene ORF was the shortest among those of the previously reported subunits derived by the D genome. A further comparison of Dy13t amino acid sequence with those of the subunits characterized from the A, B, D, R genomes of Triticeae showed that the smaller size of the Dy13t subunit was associated with a reduction in the size of its repetitive domain.

  11. Gel-based chemical cross-linking analysis of 20S proteasome subunit-subunit interactions in breast cancer.

    Science.gov (United States)

    Song, Hai; Xiong, Hua; Che, Jing; Xi, Qing-Song; Huang, Liu; Xiong, Hui-Hua; Zhang, Peng

    2016-08-01

    The ubiquitin-proteasome system plays a pivotal role in breast tumorigenesis by controlling transcription factors, thus promoting cell cycle growth, and degradation of tumor suppressor proteins. However, breast cancer patients have failed to benefit from proteasome inhibitor treatment partially due to proteasome heterogeneity, which is poorly understood in malignant breast neoplasm. Chemical crosslinking is an increasingly important tool for mapping protein three-dimensional structures and proteinprotein interactions. In the present study, two cross-linkers, bis (sulfosuccinimidyl) suberate (BS(3)) and its water-insoluble analog disuccinimidyl suberate (DSS), were used to map the subunit-subunit interactions in 20S proteasome core particle (CP) from MDA-MB-231 cells. Different types of gel electrophoresis technologies were used. In combination with chemical cross-linking and mass spectrometry, we applied these gel electrophoresis technologies to the study of the noncovalent interactions among 20S proteasome subunits. Firstly, the CP subunit isoforms were profiled. Subsequently, using native/SDSPAGE, it was observed that 0.5 mmol/L BS(3) was a relatively optimal cross-linking concentration for CP subunit-subunit interaction study. 2-DE analysis of the cross-linked CP revealed that α1 might preinteract with α2, and α3 might pre-interact with α4. Moreover, there were different subtypes of α1α2 and α3α4 due to proteasome heterogeneity. There was no significant difference in cross-linking pattern for CP subunits between BS(3) and DSS. Taken together, the gel-based characterization in combination with chemical cross-linking could serve as a tool for the study of subunit interactions within a multi-subunit protein complex. The heterogeneity of 20S proteasome subunit observed in breast cancer cells may provide some key information for proteasome inhibition strategy. PMID:27465334

  12. Nonfouling hydrogels formed from charged monomer subunits.

    Science.gov (United States)

    Dobbins, Sean C; McGrath, Daniel E; Bernards, Matthew T

    2012-12-13

    A critical challenge in the field of biomaterials is the often undesirable, but immediate, coating of implants with nonspecifically adsorbed proteins upon contact with bodily fluids. Prior research has shown that overall neutral materials containing a homologous arrangement of mixed charges exhibit nonfouling properties. This has been widely demonstrated for zwitterionic materials and more recently for coatings containing an equimolar mixture of positively and negatively charged monomer subunits. In this investigation it is demonstrated that nonfouling hydrogels can be formed through this approach, and the physical properties of the resulting materials are thoroughly characterized. In particular, hydrogels were formed from mixtures of [2-(methacryloyloxy)ethyl]trimethylammonium chloride (TM) and 3-sulfopropyl methacrylate potassium salt (SA) monomers with varying concentrations of a triethylene glycol dimethacrylate (TEGDMA) cross-linker. The swelling, weight percentage water, surface zeta potential, and compressional properties of the gels were characterized, and the nonfouling properties were demonstrated using enzyme-linked immunosorbant assays for both negatively charged fibrinogen and positively charged lysozyme. The results confirm that the TM:SA hydrogel systems have nonfouling properties that are equivalent to established nonfouling controls. Additionally, even though the gels were resistant to nonspecific protein adsorption, a composition analysis suggests that there is room to further improve the nonfouling performance because there is a slight enrichment of the SA monomer relative to the TM monomer. PMID:23189949

  13. Three utilization patterns of the renovated Moste hydro power plant on an electricity market of power and ancillary services

    International Nuclear Information System (INIS)

    In addition to electricity, most hydro power plants can offer also the ancillary services: secondary and tertiary control reserve. On emerging electricity markets the need for these additional services is becoming more and more important, recognised and also paid. However, for each plant, there is some interdependence among those options. The same plant cannot provide maximal peaking electricity, maximal secondary control reserve as well as maximal tertiary control reserve at the same time. The generation capabilities of the plant must thus be partitioned properly among those options so as to achieve some overall goal (e.g. the maximum of revenue, etc.). This article briefly presents those options for the renovated Moste cascade on the upper Sava river near Bled in Slovenia. A small but effective mixed integer linear programme has been used. (author)

  14. The business of medicine: how to overcome financial obstacles and secure financing for your private practice and ancillary services business.

    Science.gov (United States)

    Nayor, David

    2012-01-01

    Doctors across the country who operate private medical practices are facing increasing financial obstacles, namely shrinking income as a result of rising costs and lower reimbursements. In addition, as hospitals have become overburdened many physicians have opened up private surgical centers; magnetic resonance imaging and computed tomography and positron emission tomography scanning facilities; pathology labs; colonoscopy/endoscopy suites; lithotripsy centers; and other medical businesses typically performed within the hospital. Moreover, many doctors seek loans to purchase existing practices or for their capital contribution in medical partnerships. The past decade has thus seen a significant increase in the number of doctors taking out small business loans. Indeed, banks view the healthcare industry as a large growth market. This article includes practical information, advice, and resources to help doctors to secure bank financing for their practices, ancillary services business, real estate, and equipment on the best possible market terms. PMID:22920034

  15. A novel role of the tumor size in pancreatic cancer as an ancillary factor for predicting resectability

    Directory of Open Access Journals (Sweden)

    Kun-Chun Chiang

    2014-01-01

    Results: The tumor size in unresectable groups is significantly larger than that in the resectable group. The area under the ROC curve was 0.73 (95% confidence interval [CI], 0.665-0.789, which represented a good correlation between the tumor size and pancreatic cancer resectability. The PCA patients with a tumor diameter of > 4.8 cm had a 5.043-fold higher chance of unresectability than did those with a tumor diameter 4.8 cm is a potential ancillary parameter for determining the resectability of PCA in addition to traditional image studies. Diagnosis laparoscopy may be indicated for radiologically resectable PCA patients with tumor size > 4.8 cm to prevent unnecessary laparotomy.

  16. The effect of ancillary data on components of the earth's radiation budget as computed from satellite measurements

    International Nuclear Information System (INIS)

    Full text: Various ancillary data, describing the radiative transfer properties of the atmosphere and of the erth's surface, are required to determine the cloud field properties within the atmosphere and the radiation budget components at its boundaries from related satellite measurements. These is in particular. information on the surface reflectance and skin temperature to identify clouds and aerosols in the troposphere. Vertical profiles of atmospheric gas concentrations and of the aerosols as well are often proscribed from direct sampling over a small ensemble of areas. Most quantities undergo in particular over continents strong diurnal variations. Such information on quantities, which often vary strongly in space and time, needs also be derived from satellite measurements. Thus it is expected that it contains systematic errors and also artefacts which are expected to propagate into the final results on the Earth's cloud fields and radiation budget components. With examples from the International Satellite Cloud Climatology Project (ISCCP), from the GEWEX Surface Radiation Budget Project (SRB) and the Cloud and Radiation Experiments (CERES), which all aim for global fields and long time series, we were able to identify error sources, which if not corrected already lead to erroneous conclusions in the interpretation of time series. During the presentation several examples will be discussed including also methodological errors (e.g. computation of the insolation at the Top of the Atmosphere and of the Pinatubo aerosol clouds). We conclude, that at least all data of these three projects need to be re-analyzed preceded by a reanalysis of all ancillary data. This conclusion hold also for all other project making use of the results of all three projects including the retrieval of aerosols from satellite measurements. The presently available data sets of all three projects should not yet be used for analyses of longer time series. Our efforts are part of a complete

  17. Echinococcus granulosus antigen B structure: subunit composition and oligomeric states.

    Directory of Open Access Journals (Sweden)

    Karina M Monteiro

    Full Text Available BACKGROUND: Antigen B (AgB is the major protein secreted by the Echinococcus granulosus metacestode and is involved in key host-parasite interactions during infection. The full comprehension of AgB functions depends on the elucidation of several structural aspects that remain unknown, such as its subunit composition and oligomeric states. METHODOLOGY/PRINCIPAL FINDINGS: The subunit composition of E. granulosus AgB oligomers from individual bovine and human cysts was assessed by mass spectrometry associated with electrophoretic analysis. AgB8/1, AgB8/2, AgB8/3 and AgB8/4 subunits were identified in all samples analyzed, and an AgB8/2 variant (AgB8/2v8 was found in one bovine sample. The exponentially modified protein abundance index (emPAI was used to estimate the relative abundance of the AgB subunits, revealing that AgB8/1 subunit was relatively overrepresented in all samples. The abundance of AgB8/3 subunit varied between bovine and human cysts. The oligomeric states formed by E. granulosus AgB and recombinant subunits available, rAgB8/1, rAgB8/2 and rAgB8/3, were characterized by native PAGE, light scattering and microscopy. Recombinant subunits showed markedly distinct oligomerization behaviors, forming oligomers with a maximum size relation of rAgB8/3>rAgB8/2>rAgB8/1. Moreover, the oligomeric states formed by rAgB8/3 subunit were more similar to those observed for AgB purified from hydatid fluid. Pressure-induced dissociation experiments demonstrated that the molecular assemblies formed by the more aggregative subunits, rAgB8/2 and rAgB8/3, also display higher structural stability. CONCLUSIONS/SIGNIFICANCE: For the first time, AgB subunit composition was analyzed in samples from single hydatid cysts, revealing qualitative and quantitative differences between samples. We showed that AgB oligomers are formed by different subunits, which have distinct abundances and oligomerization properties. Overall, our findings have significantly

  18. Mutations in GABAA receptor subunits associated with genetic epilepsies.

    Science.gov (United States)

    Macdonald, Robert L; Kang, Jing-Qiong; Gallagher, Martin J

    2010-06-01

    Mutations in inhibitory GABAA receptor subunit genes (GABRA1, GABRB3, GABRG2 and GABRD) have been associated with genetic epilepsy syndromes including childhood absence epilepsy (CAE), juvenile myoclonic epilepsy (JME), pure febrile seizures (FS), generalized epilepsy with febrile seizures plus (GEFS+), and Dravet syndrome (DS)/severe myoclonic epilepsy in infancy (SMEI). These mutations are found in both translated and untranslated gene regions and have been shown to affect the GABAA receptors by altering receptor function and/or by impairing receptor biogenesis by multiple mechanisms including reducing subunit mRNA transcription or stability, impairing subunit folding, stability, or oligomerization and by inhibiting receptor trafficking. PMID:20308251

  19. Telomerase Holoenzyme Proteins and Processivity Subunit in Tetrahymena thermophila

    OpenAIRE

    Min, Bosun

    2009-01-01

    Telomeres are specialized protein-DNA structures that protect the ends of linear chromosomes, and they are maintained by the telomerase ribonucleoprotein (RNP) enzyme complex. Recombinant telomerase RNP with catalytic activity contains, at a minimum, the catalytic reverse transcriptase subunit (TERT) and the telomerase RNA (TER). However, endogenous telomerase is a much larger holoenzyme complex, with telomerase-associated subunits that contribute to RNP assembly and regulation. Telomerase-as...

  20. Echinococcus granulosus Antigen B Structure: Subunit Composition and Oligomeric States

    OpenAIRE

    Monteiro, Karina M.; Cardoso, Mateus B.; Follmer, Cristian; da Silveira, Nádya P.; Vargas, Daiani M.; Kitajima, Elliot W.; Zaha, Arnaldo; Ferreira, Henrique B.

    2012-01-01

    Background Antigen B (AgB) is the major protein secreted by the Echinococcus granulosus metacestode and is involved in key host-parasite interactions during infection. The full comprehension of AgB functions depends on the elucidation of several structural aspects that remain unknown, such as its subunit composition and oligomeric states. Methodology/Principal Findings The subunit composition of E. granulosus AgB oligomers from individual bovine and human cysts was assessed by mass spectromet...

  1. Bacterial cellulose biosynthesis: diversity of operons, subunits, products and functions

    OpenAIRE

    Römling, Ute; Galperin, Michael Y

    2015-01-01

    Recent studies of bacterial cellulose biosynthesis, including structural characterization of a functional cellulose synthase complex, provided the first mechanistic insight into this fascinating process. In most studied bacteria, just two subunits, BcsA and BcsB, are necessary and sufficient for the formation of the polysaccharide chain in vitro. Other subunits – which differ among various taxa – affect the enzymatic activity and product yield in vivo by modulating expression of biosynthesis ...

  2. A fully automatic tool to perform accurate flood mapping by merging remote sensing imagery and ancillary data

    Science.gov (United States)

    D'Addabbo, Annarita; Refice, Alberto; Lovergine, Francesco; Pasquariello, Guido

    2016-04-01

    Flooding is one of the most frequent and expansive natural hazard. High-resolution flood mapping is an essential step in the monitoring and prevention of inundation hazard, both to gain insight into the processes involved in the generation of flooding events, and from the practical point of view of the precise assessment of inundated areas. Remote sensing data are recognized to be useful in this respect, thanks to the high resolution and regular revisit schedules of state-of-the-art satellites, moreover offering a synoptic overview of the extent of flooding. In particular, Synthetic Aperture Radar (SAR) data present several favorable characteristics for flood mapping, such as their relative insensitivity to the meteorological conditions during acquisitions, as well as the possibility of acquiring independently of solar illumination, thanks to the active nature of the radar sensors [1]. However, flood scenarios are typical examples of complex situations in which different factors have to be considered to provide accurate and robust interpretation of the situation on the ground: the presence of many land cover types, each one with a particular signature in presence of flood, requires modelling the behavior of different objects in the scene in order to associate them to flood or no flood conditions [2]. Generally, the fusion of multi-temporal, multi-sensor, multi-resolution and/or multi-platform Earth observation image data, together with other ancillary information, seems to have a key role in the pursuit of a consistent interpretation of complex scenes. In the case of flooding, distance from the river, terrain elevation, hydrologic information or some combination thereof can add useful information to remote sensing data. Suitable methods, able to manage and merge different kind of data, are so particularly needed. In this work, a fully automatic tool, based on Bayesian Networks (BNs) [3] and able to perform data fusion, is presented. It supplies flood maps

  3. Estimating the distribution of snow depth via artificial neural networks combined with MODIS snow cover area and ancillary topographic data

    Science.gov (United States)

    Hou, Jinliang; Huang, Chunlin

    2016-04-01

    Accurately estimate the distribution of snow depth (SD) is particularly difficult in mountainous environments given the complex topography, strong seasonal transition, and scarce observations. Passive microwave snow depth retrievals are too coarse to resolve small-scale terrain-induced variability; Optical sensors have the ability to determine the snow coverage extent at higher spatial resolution but not SD. By taking advantage of long time moderate-resolution optical sensors (MODIS) fractional snow cover (FSC) data series, the cubic spline interpolation algorithm is used to fill in data gaps caused by clouds in MODIS FSC Products. An innovative method based on multilayer feedforward artificial neural network (ANN) is presented to generate SD at a 500 m spatial resolution. This is trained with back propagation to learn the relationship between SD and FSC, Latitude and longitude, and ancillary topographic (e.g. elevation, slope, aspect) data. In this study, daily snow depth observations at 42 meteorological stationsare chosen to examine the proposed method during 2004 to 2005 snow seasons (from 1 November 2004 to 31 March 2005, 151 days) in northern Xinjiang Province, China. Among them, FSC, Latitude and longitude, and ancillary topographic data extracted from 35 sites are used as input information, and corresponding ground-based SD observations are used as desired output of ANN, thus a total of 151*35 samples are included in the ANN training set; Corresponding data from other 7 sites are used as independent test sample set (151*7 samples) to test the generalization ability of the ANN. Preliminary experimental results are very encouraging compared with the traditional multiple regression method. The performance evaluation results shows that the ANN derived SD have much higher coefficient of determination (R2) and lower root-mean-square error (RMSE), with R2 of 0.89 and 0.88, RMSE of 0.07 and 0.08, the mean absolute error of 2.3 and 2.3 cm for training and test

  4. Bis-cyclometalated iridium(III) complexes bearing ancillary guanidinate ligands. Synthesis, structure, and highly efficient electroluminescence.

    Science.gov (United States)

    Rai, Virendra Kumar; Nishiura, Masayoshi; Takimoto, Masanori; Zhao, Shanshan; Liu, Yu; Hou, Zhaomin

    2012-01-16

    We report the synthesis, structure, and photophysical and electroluminescent (EL) properties of a series of heteroleptic bis(pyridylphenyl)iridium(III) complexes with various ancillary guanidinate ligands. The reaction of the bis(pyridylphenyl)iridium(III) chloride [(ppy)(2)Ir(μ-Cl)](2) with the lithium salt of various guanidine ligands Li{(N(i)Pr)(2)C(NR(1)R(2))} at 80 °C gave in 60-80% yield the corresponding heteroleptic bis(pyridylphenyl)/guanidinate iridium(III) complexes having a general formula of [(ppy)(2)Ir{(N(i)Pr)(2)C(NR(1)R(2))}], where NR(1)R(2) = NPh(2) (1), N(C(6)H(4)(t)Bu-4)(2) (2), carbazolyl (3), 3,6-bis(tert-butyl)carbazolyl (4), N(C(6)H(4))(2)S (5), N(C(6)H(4))(2)O (6), indolyl (7), NEt(2) (8), N(i)Pr(2) (9), N(i)Bu(2) (10), and N(SiMe(3))(2) (11). These heteroleptic cyclometalated (C^N) iridium(III) complexes showed intense absorption bands in the UV region assignable to π-π* transitions and weaker metal-to-ligand charge-transfer transitions extending to the visible region. These complexes also showed intense emissions at room temperature. Their photoluminescence spectra were influenced to some extent by the ancillary guanidinate ligands, giving λ(max) values in the range of 528-560 nm with quantum yields (Φ) of 0.16-0.37 and lifetimes of 0.61-1.43 μs. Organic light-emitting diodes were fabricated by the use of these complexes as dopants in various concentrations (5-100%) in a N,N'-dicarbazolylbiphenyl host. High current efficiency (η(c); up to 137.4 cd/A) and power efficiency (η(p); up to 45.7 lm/W) were observed under appropriate conditions. Their high EL efficiency may result from efficient trapping and radiative relaxation of the excitons formed in the EL process. Because of the steric hindrance of the guanidinate ligands, no significant intermolecular interaction was observed in these complexes, thus leading to the reduction of self-quenching and triplet-triplet annihilation at high currents. The EL emission color could be changed

  5. Functional diversity of complex I subunits in Candida albicans mitochondria.

    Science.gov (United States)

    Li, Dongmei; She, Xiaodong; Calderone, Richard

    2016-02-01

    Our interest in the mitochondria of Candida albicans has progressed to the identification of several proteins that are critical to complex I (CI) activity. We speculated that there should be major functional differences at the protein level between mammalian and fungal mitochondria CI. In our pursuit of this idea, we were helped by published data of CI subunit proteins from a broad diversity of species that included two subunit proteins that are not found in mammals. These subunit proteins have been designated as Nuo1p and Nuo2p (NADH-ubiquinone oxidoreductases). Since functional assignments of both C. albicans proteins were unknown, other than having a putative NADH-oxidoreductase activity, we constructed knock-out strains that could be compared to parental cells. The relevance of our research relates to the critical roles of both proteins in cell biology and pathogenesis and their absence in mammals. These features suggest they may be exploited in antifungal drug discovery. Initially, we characterized Goa1p that apparently regulates CI activity but is not a CI subunit protein. We have used the goa1∆ for comparisons to Nuo1p and Nuo2p. We have demonstrated the critical role of these proteins in maintaining CI activities, virulence, and prolonging life span. More recently, transcriptional profiling of the three mutants and an ndh51∆ (protein is a highly conserved CI subunit) has revealed that there are overlapping yet also different functional assignments that suggest subunit specificity. The differences and similarities of each are described below along with our hypotheses to explain these data. Our conclusion and perspective is that the C. albicans CI subunit proteins are highly conserved except for two that define non-mammalian functions. PMID:26373419

  6. Cytochrome c oxidase: evolution of control via nuclear subunit addition.

    Science.gov (United States)

    Pierron, Denis; Wildman, Derek E; Hüttemann, Maik; Markondapatnaikuni, Gopi Chand; Aras, Siddhesh; Grossman, Lawrence I

    2012-04-01

    According to theory, present eukaryotic cells originated from a beneficial association between two free-living cells. Due to this endosymbiotic event the pre-eukaryotic cell gained access to oxidative phosphorylation (OXPHOS), which produces more than 15 times as much ATP as glycolysis. Because cellular ATP needs fluctuate and OXPHOS both requires and produces entities that can be toxic for eukaryotic cells such as ROS or NADH, we propose that the success of endosymbiosis has largely depended on the regulation of endosymbiont OXPHOS. Several studies have presented cytochrome c oxidase as a key regulator of OXPHOS; for example, COX is the only complex of mammalian OXPHOS with known tissue-specific isoforms of nuclear encoded subunits. We here discuss current knowledge about the origin of nuclear encoded subunits and the appearance of different isozymes promoted by tissue and cellular environments such as hypoxia. We also review evidence for recent selective pressure acting on COX among vertebrates, particularly in primate lineages, and discuss the unique pattern of co-evolution between the nuclear and mitochondrial genomes. Finally, even though the addition of nuclear encoded subunits was a major event in eukaryotic COX evolution, this does not lead to emergence of a more efficient COX, as might be expected from an anthropocentric point of view, for the "higher" organism possessing large brains and muscles. The main function of these subunits appears to be "only" to control the activity of the mitochondrial subunits. We propose that this control function is an as yet under appreciated key point of evolution. Moreover, the importance of regulating energy supply may have caused the addition of subunits encoded by the nucleus in a process comparable to a "domestication scenario" such that the host tends to control more and more tightly the ancestral activity of COX performed by the mtDNA encoded subunits. PMID:21802404

  7. Pituitary glycoprotein hormone a-subunit secretion by cirrhotic patients

    Directory of Open Access Journals (Sweden)

    Oliveira M.C.

    1999-01-01

    Full Text Available Secretion of the a-subunit of pituitary glycoprotein hormones usually follows the secretion of intact gonadotropins and is increased in gonadal failure and decreased in isolated gonadotropin deficiency. The aim of the present study was to determine the levels of the a-subunit in the serum of patients with cirrhosis of the liver and to compare the results obtained for eugonadal cirrhotic patients with those obtained for cirrhotic patients with hypogonadotropic hypogonadism. Forty-seven of 63 patients with cirrhosis (74.6% presented hypogonadism (which was central in 45 cases and primary in 2, 7 were eugonadal, and 9 women were in normal menopause. The serum a-subunit was measured by the fluorimetric method using monoclonal antibodies. Cross-reactivity with LH, TSH, FSH and hCG was 6.5, 1.2, 4.3 and 1.1%, respectively, with an intra-assay coefficient of variation (CV of less than 5% and an interassay CV of 5%, and sensitivity limit of 4 ng/l. The serum a-subunit concentration ranged from 36 to 6253 ng/l, with a median of 273 ng/l. The median was 251 ng/l for patients with central hypogonadism and 198 ng/l for eugonadal patients. The correlation between the a-subunit and basal LH levels was significant both in the total sample (r = 0.48, P<0.01 and in the cirrhotic patients with central hypogonadism (r = 0.33, P = 0.02. Among men with central hypogonadism there was a negative correlation between a-subunit levels and total testosterone levels (r = 0.54, P<0.01 as well as free testosterone levels (r = -0.53, P<0.01. In conclusion, although the a-subunit levels are correlated with LH levels, at present they cannot be used as markers for hypogonadism in patients with cirrhosis of the liver.

  8. Assistance in chemistry and chemical processes related to primary, secondary and ancillary systems of nuclear power plants

    International Nuclear Information System (INIS)

    Argentina is currently running two nuclear power plants: Atucha I (CNA I) and Embalse (CNE) operated by Nucleoelectrica Argentina (NASA) whereas the National Atomic Energy Commission (CNEA), among other activities, is responsible for research and development in the nuclear field, operates research reactors and carries out projects related to them. In particular, the Reactor Chemistry Section personnel (currently part of the Chemistry Dept.) has been working on the field of reactor water chemistry for more than 25 years, on research and support to the NPPs chemistry department. Though the most relevant tasks have been connected to primary and secondary circuits chemistry, ancillary systems show along the time unexpected problems or feasible improvements originated in the undergoing operating time as well as in phenomena not foreseen by the constructors. In the present paper are presented the tasks performed in relation to the following systems of Embalse NPP: 1) Heavy water upgrade column preliminary water treatment; 2) Liquid waste system preliminary water treatment; and 3) Primary heat transport system coolant crud composition. (author)

  9. Proposal for the award of an industrial services contract for operation of the hostels, apartments and ancillary premises

    CERN Document Server

    2000-01-01

    This document concerns the award of an Industrial Services contract for operation of the hostels, apartments and ancillary premises run by the CERN Housing Service. Following a market survey carried out among 32 firms in ten Member States, a call for tenders (IT-2404/AS/Rev.) was sent on 5 April 2000 to one firm and three consortia in four Member States. By the closing date, CERN had received tenders from the firm and the three consortia. The Finance Committee is invited to agree to the negotiation of a contract with the consortium VIENNA INTERNATIONAL HOTEL MANAGEMENT (AT) - SEREG (CH), the lowest bidder, for an initial period of five years, to enter into force on 1 January 2001, for a total amount of 6 871 850 Swiss francs, not subject to revision until 31 December 2001. The contract will include an option for two one-year extensions beyond the initial five-year period. The consortium has indicated the following distribution by country of the contract value covered by this adjudication proposal: CH-60%, AT-...

  10. Study of Droplet Activation in Thin Clouds Using Ground-Based Raman Lidar and Ancillary Remote Sensors

    Science.gov (United States)

    Rosoldi, Marco; Madonna, Fabio; Gumà Claramunt, Pilar; Pappalardo, Gelsomina

    2016-06-01

    A methodology for the study of cloud droplet activation based on the measurements performed with ground-based multi-wavelength Raman lidars and ancillary remote sensors collected at CNR-IMAA observatory, Potenza, South Italy, is presented. The study is focused on the observation of thin warm clouds. Thin clouds are often also optically thin: this allows the cloud top detection and the full profiling of cloud layers using ground-based Raman lidar. Moreover, broken clouds are inspected to take advantage of their discontinuous structure in order to study the variability of optical properties and water vapor content in the transition from cloudy regions to cloudless regions close to the cloud boundaries. A statistical study of this variability leads to identify threshold values for the optical properties, enabling the discrimination between clouds and cloudless regions. These values can be used to evaluate and improve parameterizations of droplet activation within numerical models. A statistical study of the co-located Doppler radar moments allows to retrieve droplet size and vertical velocities close to the cloud base. First evidences of a correlation between droplet vertical velocities measured at the cloud base and the aerosol effective radius observed in the cloud-free regions of the broken clouds are found.

  11. Chronic stress, inflammation, and glucose regulation in U.S. Hispanics from the HCHS/SOL Sociocultural Ancillary Study.

    Science.gov (United States)

    McCurley, Jessica L; Mills, Paul J; Roesch, Scott C; Carnethon, Mercedes; Giacinto, Rebeca E; Isasi, Carmen R; Teng, Yanping; Sotres-Alvarez, Daniela; Llabre, Maria M; Penedo, Frank J; Schneiderman, Neil; Gallo, Linda C

    2015-08-01

    Diabetes prevalence is rising rapidly, and diabetes disproportionately affects Hispanics and other underserved groups. Chronic stress may contribute to diabetes risk, but few studies have examined this relationship in U.S. Hispanics. We examined associations of chronic stress with fasting glucose, glucose tolerance, and glycosylated hemoglobin (HbA1c) in Hispanics without diabetes, and also assessed indirect effects of stress through inflammation (CRP). Participants were 3,923 men and women, aged 18-74, without diabetes, from the four U.S. field centers (Bronx, NY; Chicago, IL; Miami, FL; San Diego, CA) of the Hispanic Community Health Study/Study of Latinos (HCHS/SOL) Sociocultural Ancillary study. Participants completed a measure of chronic life stress and a physical exam with oral glucose tolerance test. In a multivariate regression analysis with adjustment for demographic and health covariates, higher chronic stress was related to higher fasting glucose (standardized regression coefficient: β = .09, p stress through inflammation. Findings suggest that higher chronic stress is associated with poorer glucose regulation in Hispanics, prior to the onset of a clinical diabetes diagnosis. PMID:25898909

  12. microRNA in situ hybridization for miR-211 detection as an ancillary test in melanoma diagnosis.

    Science.gov (United States)

    Babapoor, Sankhiros; Horwich, Michael; Wu, Rong; Levinson, Shauna; Gandhi, Manoj; Makkar, Hanspaul; Kristjansson, Arni; Chang, Mary; Dadras, Soheil S

    2016-05-01

    Some melanocytic tumors can be histologically ambiguous causing diagnostic difficulty, which could lead to overtreatment of benign lesions with an unwarranted psychological distress or undertreatment of malignant cancers. Previously, we demonstrated that significantly decreased miR-211 expression in melanomas compared with melanocytic nevi could accurately discriminate malignant from benign tumors. Herein we show microRNA in situ hybridization for fluorescent detection of miR-211, suitable for paraffin-embedded tissues in 109 primary melanocytic tumors. miR-211 expression was significantly lower in melanomas vs nevi (Pnuclear atypia. All 35 melanocytic tumors with Spitz morphology expressed miR-211 independent of morphological classification, where clinical follow-up of these patients showed no recurrence at the site or metastasis in mean and median of 3 (ranging 2-5) years. Moreover, a decision tree learning analysis selected age and miR-211 miRNA in situ hybridization as the predictive variables for benign or malignant outcome in 88 patients correctly classified 92% (81 out of 88) of cases as proven by receiver operating characteristic curve (area under the curve=0.9029). These results support miR-211 as a leading miRNA candidate for melanoma diagnosis and miRNA in situ hybridization as a uniquely uncomplicated ancillary test. PMID:26916074

  13. Ancillary therapy of intranasal T-LysYal® for patients with allergic, non-allergic, and mixed rhinitis.

    Science.gov (United States)

    Gelardi, M; Taliente, S; Fiorella, M L; Quaranta, N; Ciancio, G; Russo, C; Mola, P; Ciofalo, A; Zambetti, G; Caruso Armone, A; Cantone, E; Ciprandi, G

    2016-01-01

    Allergic rhinitis (AR) is caused by an IgE-mediated inflammatory reaction. Non-allergic rhinitis (NAR) is characterized by a non-IgE-mediated pathogenesis. Frequently, patients have the two disorders associated: such as mixed rhinitis (MR). Hyaluronic acid (HA) is a fundamental component of the human connective tissue. HA may exert anti-inflammatory and immune-modulating activities. Recently, an intranasal HA formulation was proposed: a supramolecular system containing lysine hyaluronate, thymine and sodium chloride (T-LysYal®). This randomized study investigated whether intranasal T-LysYal® (rinoLysYal®, Farmigea, Italy) was able to reduce symptom severity, endoscopic features, and nasal cytology in 89 patients (48 males and 41 females, mean age 36.3±7.1 years) with AR, NAR, and MR. Patients were treated with intranasal T-LysYal® or isotonic saline solution as adjunctive therapy to nasal corticosteroid and oral antihistamine for 4 weeks. Patients were visited at baseline, after treatment and after 4-week follow-up. Intranasal T-LysYal® treatment significantly reduced the quote of patients with symptoms, endoscopic features, and inflammatory cells. In conclusion, the present study demonstrates that intranasal T-LysYal® is able, as ancillary therapy, to significantly improve patients with AR, NAR, and MR, and its effect is long lasting. PMID:27049100

  14. Subunit interactions change the heme active-site geometry in p-cresol methylhydroxylase.

    OpenAIRE

    McLendon, G L; Bagby, S; Charman, J A; Driscoll, P. C.; McIntire, W S; Mathews, F. S.; Hill, H A

    1991-01-01

    The enzyme p-cresol methylhydroxylase [4-cresol: (acceptor) oxidoreductase (methyl-hydroxylating), EC 1.17.99.1] contains two subunits: a cytochrome c (electron transfer) subunit (cytochrome cpc) and a flavin (catalytic) subunit. When these subunits are separated by isoelectric focusing, a stable cytochrome subunit is obtained. Significant differences are observed between the one-dimensional NMR spectra of oxidized cytochrome cpc and of oxidized p-cresol methylhydroxylase. Analysis of the two...

  15. Structure of the human protein kinase CK2 catalytic subunit CK2α' and interaction thermodynamics with the regulatory subunit CK2β

    DEFF Research Database (Denmark)

    Bischoff, Nils; Olsen, Birgitte; Raaf, Jennifer; Bretner, Maria; Issinger, Olaf-Georg; Niefind, Karsten

    2011-01-01

    Protein kinase CK2 (formerly "casein kinase 2") is composed of a central dimer of noncatalytic subunits (CK2β) binding two catalytic subunits. In humans, there are two isoforms of the catalytic subunit (and an additional splicing variant), one of which (CK2α) is well characterized. To supplement ...

  16. Optimal Policies for Simultaneous Energy Consumption and Ancillary Service Provision for Flexible Loads under Stochastic Prices and No Capacity Reservation Constraint

    OpenAIRE

    Kefayati, Mahdi; Baldick, Ross

    2014-01-01

    Flexible loads, i.e. the loads whose power trajectory is not bound to a specific one, constitute a sizable portion of current and future electric demand. This flexibility can be used to improve the performance of the grid, should the right incentives be in place. In this paper, we consider the optimal decision making problem faced by a flexible load, demanding a certain amount of energy over its availability period, subject to rate constraints. The load is also capable of providing Ancillary ...

  17. Synthesis and characterization of blue phosphorescent cyclometalated Ir(III) complexes containing 2-(imidazol-2-yl)pyridine as ancillary ligand

    International Nuclear Information System (INIS)

    Four new blue phosphorescent iridium complexes containing 2-(fluoro substituted phenyl)pyridine as the cyclometalated ligands and 2-(imidazol-2-yl)pyridine as an ancillary ligand have been synthesized and characterized. The complexes have the general structure (CcircumflexN)2Ir(pym), where CcircumflexN are cyclometalating ligands (e.g., 2-(2,4-difluorophenyl)pyridine (24f2ppyH), 2-(3,4-difluorophenyl)pyridine (34f2ppyH), 2-(3,5-difluorophenyl)pyridine (35f2ppyH), and 2-(3,4,5-trifluorophenyl)pyridine (345f3ppyH)), pym is 2-(imidazol-2-yl)pyridine (pymH). The absorption, emission, and cyclic voltammetry of the complexes were systematically investigated. The (46f2ppy)2Ir(pym) has been characterized using X-ray crystallography and the electronic ground state calculated using B3LYP density functional theory. The highest occupied molecular orbital (HOMO) consists of a mixture of pym ligand (83.7%) and Ir orbitals (12.1%), while the lowest occupied molecular orbital (LUMO) is mostly on f2ppy ligands (93.4%). By replacing the ancillary ligand pic with pym can finely tune emission of the iridium complexes, showing blue luminescence at a wavelength of 467-491 nm at room temperature in CH2Cl2. - Research highlights: → Four new blue phosphorescent iridium complexes containing 2-(fluoro substituted phenyl)pyridine as the cyclometalated ligands and 2-(imidazol-2-yl)pyridine as an ancillary ligand have been synthesized and characterized. → The absorption, emission, and cyclic voltammetry of the complexes were systematically investigated. → By changing the ancillary ligand can finely tune the emission of the iridium complexes, which is a way to design and synthesize new phosphorescent iridium materials.

  18. Dengue vaccine: an update on recombinant subunit strategies.

    Science.gov (United States)

    Martin, J; Hermida, L

    2016-03-01

    Dengue is an increasing public health problem worldwide, with the four serotypes of the virus infecting over 390 million people annually. There is no specific treatment or antiviral drug for dengue, and prevention is largely limited to controlling the mosquito vectors or disrupting the human-vector contact. Despite the considerable progress made in recent years, an effective vaccine against the virus is not yet available. The development of a dengue vaccine has been hampered by many unique challenges, including the need to ensure the absence of vaccine-induced enhanced severity of disease. Recombinant protein subunit vaccines offer a safer alternative to other vaccine approaches. Several subunit vaccine candidates are presently under development, based on different structural and non-structural proteins of the virus. Novel adjuvants or immunopotentiating strategies are also being tested to improve their immunogenicity. This review summarizes the current status and development trends of subunit dengue vaccines. PMID:26982462

  19. Cholera Toxin B: One Subunit with Many Pharmaceutical Applications

    Directory of Open Access Journals (Sweden)

    Keegan J. Baldauf

    2015-03-01

    Full Text Available Cholera, a waterborne acute diarrheal disease caused by Vibrio cholerae, remains prevalent in underdeveloped countries and is a serious health threat to those living in unsanitary conditions. The major virulence factor is cholera toxin (CT, which consists of two subunits: the A subunit (CTA and the B subunit (CTB. CTB is a 55 kD homopentameric, non-toxic protein binding to the GM1 ganglioside on mammalian cells with high affinity. Currently, recombinantly produced CTB is used as a component of an internationally licensed oral cholera vaccine, as the protein induces potent humoral immunity that can neutralize CT in the gut. Additionally, recent studies have revealed that CTB administration leads to the induction of anti-inflammatory mechanisms in vivo. This review will cover the potential of CTB as an immunomodulatory and anti-inflammatory agent. We will also summarize various recombinant expression systems available for recombinant CTB bioproduction.

  20. Functional biosynthesis of an allophycocyan beta subunit in Escherichia coli.

    Science.gov (United States)

    Ge, Baosheng; Sun, Haixiang; Feng, Yang; Yang, Jinying; Qin, Song

    2009-03-01

    Allophycocyanin is a phycobiliprotein with various biological and pharmacological properties. An expression vector was constructed using CpeS as the bilin lyase for the allophycocyanin beta subunit, resulting in overexpression of a fluorescent allophycocyanin beta-subunit in Escherichia coli. A high-density cell culture was developed using a continuous feeding strategy. After 16 h of culture, the dry cell density reached 21.4 g l(-1), the expression of the allophycocyanin beta-subunit was 0.86 g l(-1) broth, and the relative chromoprotein yield was 81.4%. The recombinant protein showed spectral features similar to native allophycocyanin, which provide an efficient methodology for large-scale production of this valuable fluorescent protein. PMID:19269586

  1. NOAA Digital Orthophotography and Ancillary Oblique Imagery Collection for the Coasts of Main/New Hampshire, Massachusetts/Rhode Island/Connecticut, and Hudson River/Long Island /NY/NJ

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Project: NOAA Digital Orthophotography and Ancillary Oblique Imagery Collection for the Coasts of Main/New Hampshire, Massachusetts/Rhode Island/Connecticut, and...

  2. Routine use of ancillary investigations in staging diffuse large B-cell lymphoma improves the International Prognostic Index (IPI

    Directory of Open Access Journals (Sweden)

    Shadbolt Bruce

    2009-11-01

    Full Text Available Abstract Background The International Prognostic Index (IPI is used to determine prognosis in diffuse large B-cell lymphoma (DLBCL. One of the determinants of IPI is the stage of disease with bone marrow involvement being classified as stage IV. For the IPI, involvement on bone marrow is traditionally defined on the basis of histology with ancillary investigations used only in difficult cases to aid histological diagnosis. This study aimed to determine the effect of the routine use of flow cytometry, immunohistochemistry and molecular studies in bone marrow staging upon the IPI. Results Bone marrow trephines of 156 histologically proven DLBCL cases at initial diagnosis were assessed on routine histology, and immunohistochemistry using two T-cell markers (CD45RO and CD3, two B-cell markers (CD20 and CD79a and kappa and lambda light chains. Raw flow cytometry data on all samples were reanalysed and reinterpreted blindly. DNA extracted from archived paraffin-embedded trephine biopsy samples was used for immunoglobulin heavy chain and light chain gene rearrangement analysis. Using immunophenotyping (flow cytometry and immunohistochemistry, 30 (19.2% cases were upstaged to stage IV. A further 8 (5.1% cases were upstaged using molecular studies. A change in IPI was noted in 18 cases (11.5% on immunophenotyping alone, and 22 (14.1% cases on immunophenotyping and molecular testing. Comparison of two revised IPI models, 1 using immunophenotyping alone, and 2 using immunophenotyping with molecular studies, was performed with baseline IPI using a Cox regression model. It showed that the revised IPI model using immunophenotyping provides the best differentiation between the IPI categories. Conclusion Improved bone marrow staging using flow cytometry and immunohistochemistry improves the predictive value of the IPI in patients with DLBCL and should be performed routinely in all cases.

  3. Design of Os(II) -based sensitizers for dye-sensitized solar cells: influence of heterocyclic ancillaries.

    Science.gov (United States)

    Hu, Fa-Chun; Wang, Sheng-Wei; Planells, Miquel; Robertson, Neil; Padhy, Harihara; Du, Bo-Sian; Chi, Yun; Yang, Po-Fan; Lin, Hao-Wu; Lee, Gene-Hsiang; Chou, Pi-Tai

    2013-08-01

    A series of Os(II) sensitizers (TFOS-x, in which x=1, 2, or 3) with a single 4,4'-dicarboxy-2,2'-dipyridine (H2 dcbpy) anchor and two chelating 2-pyridyl (or 2-pyrimidyl) triazolate ancillaries was successfully prepared. Single-crystal X-ray structural analysis showed that the core geometry of the Os(II) -based sensitizers consisted of one H2 dcbpy unit and two eclipsed cis-triazolate fragments; this was notably different from the Ru(II) -based counterparts, in which the azolate (both pyrazolate and triazolate) fragments are located at the mutual trans-positions. The basic properties were extensively probed by using spectroscopic and electrochemical methods as well as time-dependent density functional theory (TD-DFT) calculations. Fabrication of dye-sensitized solar cells (DSCs) was then attempted by using the I(-) /I3 (-) -based electrolyte solution. One such DSC device, which utilized TFOS-2 as the sensitizer, showed promising performance characteristics with a short-circuit current density (JSC ) of 15.7 mA cm(-2) , an open-circuit voltage of 610 mV, a fill factor of 0.63, and a power conversion efficiency of 6.08 % under AM 1.5G simulated one-sun irradiation. Importantly, adequate incident photon-to-current conversion efficiency performances were observed for all TFOS derivatives over the wide spectral region of 450 to 950 nm, showing a panchromatic light harvesting capability that extended into the near-infrared regime. Our results underlined a feasible strategy for maximizing JSC and increasing the efficiency of DSCs. PMID:23843354

  4. Four homochiral coordination polymers contain N-acetyl-L-tyrosine and different N-donor ligand: Influence of metal cations, ancillary ligands and coordination modes

    International Nuclear Information System (INIS)

    Using the chiral ligand N-acetyl-L-tyrosine (Hacty) and maintaining identical reaction conditions, Zn(II), Co(II), and Cd(II) salts provided four novel homochiral coordination polymers ([Zn(acty)(bipy)2(H2O)2]·NO3·2H2O)n1, ([Co(acty)(bipy)2(H2O)2]·NO3·2H2O)n2, ([Cd(acty)2(bipy)H2O]·H2O)n3, and ([Cd(acty)(bpe)2(Ac)]·6H2O)n4 (bipy=4,4′-bipyridine; bpe=1,2-di(4-pyridyl)ethane) in the presence of ancillary ligands. Compounds 1 and 2 are isostructural 1D chain structures. The neighboring chains are further linked into a 3D supramolecular structure via π⋯π stacking and hydrogen bond interactions. Compound 3 shows a 2D network and 4 generates 1D infinite chains along the c-axis. Compounds 3 and 4 are further connected into 3D supramolecular network by hydrogen bond interactions. More importantly, coordination in acyl oxygen atoms and ancillary ligands (bpe) as monodentate decorating ligands in 4 are rarely reported. Ancillary ligands and metal cations significantly influence the structure of the complexes. The photoluminescence properties of 1, 3, and 4 were studied at room temperature. Circular dichroism (CD) of the complexes have been investigated. - Graphical abstract: Four new homochiral coordination polymers were prepared and structurally characterized, which investigate the influence of the ancillary ligands and metal ions on the design and synthesis of coordination polymers. Display Omitted - Highlights: • It is rarely reported that the chiral coordination polymers prepared with N-acetyl-L-tyrosine ligands. • The alkalescent acetyl oxygen atom is difficult to participate in coordination but it is happened in the N-acetyl-L-tyrosine ligands. • The ancillary ligands (4,4′-bipy and bpe) are present in an unusual coordination modes, monodentate decorating ligands in 1, 2 and 4. • Structure comparative analyses results indicate that the secondary ligands and metal ions influence the fabrication of these inorganic–organic arrangements

  5. Nascent 60S ribosomal subunits enter the free pool bound by Nmd3p.

    OpenAIRE

    Ho, J. H.; Kallstrom, G; Johnson, A. W.

    2000-01-01

    Nmd3p from yeast is required for the export of the large (60S) ribosomal subunit from the nucleus (Ho et al., 2000). Here, we show that Nmd3p forms a stable complex with free 60S subunits. Using an epitope-tagged Nmd3p, we show that free 60S subunits can be coimmunoprecipitated with Nmd3p. The interaction was specific for 60S subunits; 40S subunits were not coimmunoprecipitated. Using this coprecipitation technique and pulse-chase labeling of ribosomal subunit proteins we showed that Nmd3p bo...

  6. The Essential Anatomical Subunit Approximation Unilateral Cleft Lip Repair.

    Science.gov (United States)

    Chong, David K; Swanson, Jordan W

    2016-07-01

    The anatomical subunit approximation cleft lip repair advantageously achieves a balanced lip contour, with the line of repair hidden along seams of aesthetic subunits. Dr. David Fisher's original description of the repair reflects the considerable thought that went into the evolution of his design. As his technique has gained acceptance in the intervening 10 years, the authors note several key principles embodied in it that represent a shift in the cleft lip repair paradigm. The authors believe understanding these principles is important to mastery of the anatomical subunit technique, and facilitate its teaching. First, design a plan that adheres to anatomical subunits and perform measurements precisely. Second, identify and adequately release each cleft tissue layer from the lip and nose to enable restoration of balance. Third, drive surgical approximation through inset of the lateral muscle into the superiorly backcut medial orbicularis muscle, followed by skin closure with inferior triangle interposition above the white roll. In this article, the authors present essential components of the technique, and identify several principles that enable its successful execution. PMID:27348690

  7. Editing modifies the GABA(A) receptor subunit alpha3

    DEFF Research Database (Denmark)

    Ohlson, Johan; Pedersen, Jakob Skou; Haussler, David;

    2007-01-01

    to find selectively edited sites and combined it with bioinformatic techniques that find stem-loop structures suitable for editing. We present here the first verified editing candidate detected by this screening procedure. We show that Gabra-3, which codes for the alpha3 subunit of the GABA...

  8. Bacterial cellulose biosynthesis: diversity of operons, subunits, products, and functions.

    Science.gov (United States)

    Römling, Ute; Galperin, Michael Y

    2015-09-01

    Recent studies of bacterial cellulose biosynthesis, including structural characterization of a functional cellulose synthase complex, provided the first mechanistic insight into this fascinating process. In most studied bacteria, just two subunits, BcsA and BcsB, are necessary and sufficient for the formation of the polysaccharide chain in vitro. Other subunits - which differ among various taxa - affect the enzymatic activity and product yield in vivo by modulating (i) the expression of the biosynthesis apparatus, (ii) the export of the nascent β-D-glucan polymer to the cell surface, and (iii) the organization of cellulose fibers into a higher-order structure. These auxiliary subunits play key roles in determining the quantity and structure of resulting biofilms, which is particularly important for the interactions of bacteria with higher organisms - leading to rhizosphere colonization and modulating the virulence of cellulose-producing bacterial pathogens inside and outside of host cells. We review the organization of four principal types of cellulose synthase operon found in various bacterial genomes, identify additional bcs genes that encode components of the cellulose biosynthesis and secretion machinery, and propose a unified nomenclature for these genes and subunits. We also discuss the role of cellulose as a key component of biofilms and in the choice between acute infection and persistence in the host. PMID:26077867

  9. Emergence of ion channel modal gating from independent subunit kinetics.

    Science.gov (United States)

    Bicknell, Brendan A; Goodhill, Geoffrey J

    2016-09-01

    Many ion channels exhibit a slow stochastic switching between distinct modes of gating activity. This feature of channel behavior has pronounced implications for the dynamics of ionic currents and the signaling pathways that they regulate. A canonical example is the inositol 1,4,5-trisphosphate receptor (IP3R) channel, whose regulation of intracellular Ca(2+) concentration is essential for numerous cellular processes. However, the underlying biophysical mechanisms that give rise to modal gating in this and most other channels remain unknown. Although ion channels are composed of protein subunits, previous mathematical models of modal gating are coarse grained at the level of whole-channel states, limiting further dialogue between theory and experiment. Here we propose an origin for modal gating, by modeling the kinetics of ligand binding and conformational change in the IP3R at the subunit level. We find good agreement with experimental data over a wide range of ligand concentrations, accounting for equilibrium channel properties, transient responses to changing ligand conditions, and modal gating statistics. We show how this can be understood within a simple analytical framework and confirm our results with stochastic simulations. The model assumes that channel subunits are independent, demonstrating that cooperative binding or concerted conformational changes are not required for modal gating. Moreover, the model embodies a generally applicable principle: If a timescale separation exists in the kinetics of individual subunits, then modal gating can arise as an emergent property of channel behavior. PMID:27551100

  10. Thermostable Subunit Vaccines for Pulmonary Delivery: How Close Are We?

    DEFF Research Database (Denmark)

    Foged, Camilla

    2016-01-01

    influenza, tuberculosis, and Ebola, for which no good universal vaccines exist. At least two pharmaceutical improvements are expected to help filling this gap: i) The development of thermostable vaccine dosage forms, and ii) the full exploitation of the adjuvant technology for subunit vaccines to potentiate...

  11. Partial agonists and subunit selectivity at NMDA receptors

    DEFF Research Database (Denmark)

    Risgaard, Rune; Hansen, Kasper Bø; Clausen, Rasmus Prætorius

    2010-01-01

    Subunit-selective ligands for glutamate receptors remains an area of interest as glutamate is the major excitatory neurotransmitter in the brain and involved in a number of diseased states in the central nervous system (CNS). Few subtype-selective ligands are known, especially among the N...

  12. Bacterial cellulose biosynthesis: diversity of operons, subunits, products and functions

    Science.gov (United States)

    Römling, Ute; Galperin, Michael Y.

    2015-01-01

    Summary Recent studies of bacterial cellulose biosynthesis, including structural characterization of a functional cellulose synthase complex, provided the first mechanistic insight into this fascinating process. In most studied bacteria, just two subunits, BcsA and BcsB, are necessary and sufficient for the formation of the polysaccharide chain in vitro. Other subunits – which differ among various taxa – affect the enzymatic activity and product yield in vivo by modulating expression of biosynthesis apparatus, export of the nascent β-D-glucan polymer to the cell surface, and the organization of cellulose fibers into a higher-order structure. These auxiliary subunits play key roles in determining the quantity and structure of the resulting biofilm, which is particularly important for interactions of bacteria with higher organisms that lead to rhizosphere colonization and modulate virulence of cellulose-producing bacterial pathogens inside and outside of host cells. Here we review the organization of four principal types of cellulose synthase operons found in various bacterial genomes, identify additional bcs genes that encode likely components of the cellulose biosynthesis and secretion machinery, and propose a unified nomenclature for these genes and subunits. We also discuss the role of cellulose as a key component of biofilms formed by a variety of free-living and pathogenic bacteria and, for the latter, in the choice between acute infection and persistence in the host. PMID:26077867

  13. CMF70 is a subunit of the dynein regulatory complex.

    Science.gov (United States)

    Kabututu, Zakayi P; Thayer, Michelle; Melehani, Jason H; Hill, Kent L

    2010-10-15

    Flagellar motility drives propulsion of several important pathogens and is essential for human development and physiology. Motility of the eukaryotic flagellum requires coordinate regulation of thousands of dynein motors arrayed along the axoneme, but the proteins underlying dynein regulation are largely unknown. The dynein regulatory complex, DRC, is recognized as a focal point of axonemal dynein regulation, but only a single DRC subunit, trypanin/PF2, is currently known. The component of motile flagella 70 protein, CMF70, is broadly and uniquely conserved among organisms with motile flagella, suggesting a role in axonemal motility. Here we demonstrate that CMF70 is part of the DRC from Trypanosoma brucei. CMF70 is located along the flagellum, co-sediments with trypanin in sucrose gradients and co-immunoprecipitates with trypanin. RNAi knockdown of CMF70 causes motility defects in a wild-type background and suppresses flagellar paralysis in cells with central pair defects, thus meeting the functional definition of a DRC subunit. Trypanin and CMF70 are mutually conserved in at least five of six extant eukaryotic clades, indicating that the DRC was probably present in the last common eukaryotic ancestor. We have identified only the second known subunit of this ubiquitous dynein regulatory system, highlighting the utility of combined genomic and functional analyses for identifying novel subunits of axonemal sub-complexes. PMID:20876659

  14. Succinate dehydrogenase subunit D and succinate dehydrogenase subunit B mutation analysis in canine phaeochromocytoma and paraganglioma.

    Science.gov (United States)

    Holt, D E; Henthorn, P; Howell, V M; Robinson, B G; Benn, D E

    2014-07-01

    Phaeochromocytomas (PCs) are tumours of the adrenal medulla chromaffin cells. Paragangliomas (PGLs) arise in sympathetic ganglia (previously called extra-adrenal PCs) or in non-chromaffin parasympathetic ganglia cells that are usually non-secretory. Parenchymal cells from these tumours have a common embryological origin from neural crest ectoderm. Several case series of canine PCs and PGLs have been published and a link between the increased incidence of chemoreceptor neoplasia in brachycephalic dog breeds and chronic hypoxia has been postulated. A similar link to hypoxia in man led to the identification of germline heterozygous mutations in the gene encoding succinate dehydrogenase subunit D (SDHD) and subsequently SDHA, SDHB and SDHC in similar tumours. We investigated canine PCs (n = 6) and PGLs (n = 2) for SDHD and SDHB mutations and in one PGL found a somatic SDHD mutation c.365A>G (p.Lys122Arg) in exon 4, which was not present in normal tissue from this brachycephalic dog. Two PCs were heterozygous for both c.365A>G (p.Lys122Arg) mutation and an exon 3 silent variant c.291G>A. We also identified the heterozygous SDHB exon 2 mutation c.113G>A (p.Arg38Gln) in a PC. These results illustrate that genetic mutations may underlie tumourigenesis in canine PCs and PGLs. The spontaneous nature of these canine diseases and possible association of PGLs with hypoxia in brachycephalic breeds may make them an attractive model for studying the corresponding human tumours. PMID:24813157

  15. Effect of high and low molecular weight glutenin subunits, and subunits of gliadin on physicochemical parameters of different wheat genotypes

    Directory of Open Access Journals (Sweden)

    Mariana Souza Costa

    2013-02-01

    Full Text Available Identification of functional properties of wheat flour by specific tests allows genotypes with appropriate characteristics to be selected for specific industrial uses. The objective of wheat breeding programs is to improve the quality of germplasm bank in order to be able to develop wheat with suitable gluten strength and extensibility for bread making. The aim of this study was to evaluate 16 wheat genotypes by correlating both glutenin subunits of high and low molecular weight and gliadin subunits with the physicochemical characteristics of the grain. Protein content, sedimentation volume, sedimentation index, and falling number values were analyzed after the grains were milled. Hectoliter weight and mass of 1000 seeds were also determined. The glutenin and gliadin subunits were separated using polyacrylamide gel in the presence of sodium dodecyl sulfate. The data were evaluated using variance analysis, Pearson's correlation, principal component analysis, and cluster analysis. The IPR 85, IPR Catuara TM, T 091015, and T 091069 genotypes stood out from the others, which indicate their possibly superior grain quality with higher sedimentation volume, higher sedimentation index, and higher mass of 1000 seeds; these genotypes possessed the subunits 1 (Glu-A1, 5 + 10 (Glu-D1, c (Glu-A3, and b (Glu-B3, with exception of T 091069 genotype that possessed the g allele instead of b in the Glu-B3.

  16. Subunit composition and chromophore content of R-phycoerythrin from Porphyra haitanensis

    Science.gov (United States)

    Gao, Hong-Feng; Ji, Ming-Hou; Cao, Wen-Da

    1996-03-01

    R-phycoerythrin from Porphyra haitanensis exists in two aggregation states with different molecular weights. A more highly aggregated form, RPE I, was chromatographed on Bio-Rex 70 column with urea solution (pH 3.0) as eluent, and the molecular weights of the 3 subunits (α, β, γ) obtained were determined on SDS-PAGE at 18000, 19200 and 30000, respectively. α subunit carried two phycoerythrobilin (PEB); β subunit, three PEB and one phycourobilin (PUB); γ subunit, one PEB and three PUB chromophores. The molar ratio of α, β, and γ subunits of RPE I was 6: 6: 1, and their subunit composition was confired to be (αβ)6γ on account of the molecular weight of RPE I, 232000. A lower aggregated form, RPE II, contained α and β subunits similar to those of RPE I, but its subunit composition was the (αβ) monomer of RPE.

  17. Bigenomic transcriptional regulation of all thirteen cytochrome c oxidase subunit genes by specificity protein 1

    OpenAIRE

    Dhar, Shilpa S.; Johar, Kaid; Wong-Riley, Margaret T. T.

    2013-01-01

    Cytochrome c oxidase (COX) is one of only four known bigenomic proteins, with three mitochondria-encoded subunits and 10 nucleus-encoded ones derived from nine different chromosomes. The mechanism of regulating this multi-subunit, bigenomic enzyme is not fully understood. We hypothesize that specificity protein 1 (Sp1) functionally regulates the 10 nucleus-encoded COX subunit genes directly and the three mitochondrial COX subunit genes indirectly by regulating mitochondrial transcription fact...

  18. Regulation of expression of a soybean storage protein subunit gene. Progress report

    International Nuclear Information System (INIS)

    We have found that the methionine repression of the β-subunit gene expression is not due to degradation of the β-subunit but is due to an effect on synthesis of the β-subunit. The effect of methionine on the synthesis of the β-is due to an inhibition of β-subunit mRNA synthesis. 3 references, 1 figure

  19. Compilation, quality control, analysis, and summary of discrete suspended-sediment and ancillary data in the United States, 1901-2010

    Science.gov (United States)

    Lee, Casey J.; Glysson, G. Douglas

    2013-01-01

    Human-induced and natural changes to the transport of sediment and sediment-associated constituents can degrade aquatic ecosystems and limit human uses of streams and rivers. The lack of a dedicated, easily accessible, quality-controlled database of sediment and ancillary data has made it difficult to identify sediment-related water-quality impairments and has limited understanding of how human actions affect suspended-sediment concentrations and transport. The purpose of this report is to describe the creation of a quality-controlled U.S. Geological Survey suspended-sediment database, provide guidance for its use, and summarize characteristics of suspended-sediment data through 2010. The database is provided as an online application at http://cida.usgs.gov/sediment to allow users to view, filter, and retrieve available suspended-sediment and ancillary data. A data recovery, filtration, and quality-control process was performed to expand the availability, representativeness, and utility of existing suspended-sediment data collected by the U.S. Geological Survey in the United States before January 1, 2011. Information on streamflow condition, sediment grain size, and upstream landscape condition were matched to sediment data and sediment-sampling sites to place data in context with factors that may influence sediment transport. Suspended-sediment and selected ancillary data are presented from across the United States with respect to time, streamflow, and landscape condition. Examples of potential uses of this database for identifying sediment-related impairments, assessing trends, and designing new data collection activities are provided. This report and database can support local and national-level decision making, project planning, and data mining activities related to the transport of suspended-sediment and sediment-associated constituents.

  20. Smart microgrid hierarchical frequency control ancillary service provision based on virtual inertia concept: An integrated demand response and droop controlled distributed generation framework

    International Nuclear Information System (INIS)

    Highlights: • Detailed formulation of the microgrid static and dynamic securities based on droop control and virtual inertia concepts. • Constructing a novel objective function using frequency excursion and rate of change of frequency profiles. • Ensuring the microgrid security subject to the microgrid economic and environmental policies. • Coordinated management of demand response and droop controlled distributed generation resources. • Precise scheduling of day-ahead hierarchical frequency control ancillary services using a scenario based stochastic programming. - Abstract: Low inertia stack, high penetration levels of renewable energy source and great ratio of power deviations in a small power delivery system put microgrid frequency at risk of instability. On the basis of the close coupling between the microgrid frequency and system security requirements, procurement of adequate ancillary services from cost-effective and environmental friendly resources is a great challenge requests an efficient energy management system. Motivated by this need, this paper presents a novel energy management system that is aimed to coordinately manage the demand response and distributed generation resources. The proposed approach is carried out by constructing a hierarchical frequency control structure in which the frequency dependent control functions of the microgrid components are modeled comprehensively. On the basis of the derived modeling, both the static and dynamic frequency securities of an islanded microgrid are provided in primary and secondary control levels. Besides, to cope with the low inertia stack of islanded microgrids, novel virtual inertia concept is devised based on the precise modeling of droop controlled distributed generation resources. The proposed approach is applied to typical test microgrid. Energy and hierarchical reserve resource are scheduled precisely using a scenario-based stochastic programming methodology. Moreover, analyzing the

  1. Multi-Temporal Landsat Images and Ancillary Data for Land Use/Cover Change (LULCC Detection in the Southwest of Burkina Faso, West Africa

    Directory of Open Access Journals (Sweden)

    Benewinde J-B. Zoungrana

    2015-09-01

    Full Text Available Accurate quantification of land use/cover change (LULCC is important for efficient environmental management, especially in regions that are extremely affected by climate variability and continuous population growth such as West Africa. In this context, accurate LULC classification and statistically sound change area estimates are essential for a better understanding of LULCC processes. This study aimed at comparing mono-temporal and multi-temporal LULC classifications as well as their combination with ancillary data and to determine LULCC across the heterogeneous landscape of southwest Burkina Faso using accurate classification results. Landsat data (1999, 2006 and 2011 and ancillary data served as input features for the random forest classifier algorithm. Five LULC classes were identified: woodland, mixed vegetation, bare surface, water and agricultural area. A reference database was established using different sources including high-resolution images, aerial photo and field data. LULCC and LULC classification accuracies, area and area uncertainty were computed based on the method of adjusted error matrices. The results revealed that multi-temporal classification significantly outperformed those solely based on mono-temporal data in the study area. However, combining mono-temporal imagery and ancillary data for LULC classification had the same accuracy level as multi-temporal classification which is an indication that this combination is an efficient alternative to multi-temporal classification in the study region, where cloud free images are rare. The LULCC map obtained had an overall accuracy of 92%. Natural vegetation loss was estimated to be 17.9% ± 2.5% between 1999 and 2011. The study area experienced an increase in agricultural area and bare surface at the expense of woodland and mixed vegetation, which attests to the ongoing deforestation. These results can serve as means of regional and global land cover products validation, as they

  2. First inactive conformation of CK2 alpha, the catalytic subunit of protein kinase CK2

    DEFF Research Database (Denmark)

    Raaf, Jennifer; Issinger, Olaf-Georg; Niefind, Karsten

    2009-01-01

    The Ser/Thr kinase casein kinase 2 (CK2) is a heterotetrameric enzyme composed of two catalytic chains (CK2alpha, catalytic subunit of CK2) attached to a dimer of two noncatalytic subunits (CK2beta, noncatalytic subunit of CK2). CK2alpha belongs to the superfamily of eukaryotic protein kinases...

  3. Cloning and expression of the human N-methyl-D-aspartate receptor subunit NR3A

    DEFF Research Database (Denmark)

    Eriksson, Maria; Nilsson, Anna; Froelich-Fabre, Susanne;

    2002-01-01

    Native N-methyl-D-aspartate (NMDA) receptors are heteromeric assemblies of four or five subunits. The NMDA receptor subunits, NR1, NR2A, NR2B, NR2C, and NR2D have been cloned in several species, including man. The NR3A subunit, which in rodents is predominantly expressed during early development,...

  4. Localization of the catalytic subunit of cyclic AMP-dependent. Protein kinase in cultured cells using a specific antibody

    OpenAIRE

    1982-01-01

    We developed a specific antibody to the catalytic subunit (C-subunit) of cyclic AMP-dependent protein kinase and used it to localize C- subunit in cultured cells. C-subunit antigen was purified from bovine cardiac muscle and cross-linked to hemocyanin with glutaraldehyde. Immunized goat serum showed a low titer of antibody after boosting; it was enriched 100-fold by affinity chromatography on catalytic subunit- Sepharose. The antibody immunoprecipitated C-subunit from type I and type II holoe...

  5. Developments of Subunit and VLP Vaccines Against Influenza A Virus

    Institute of Scientific and Technical Information of China (English)

    Ma-ping Deng; Zhi-hong Hu; Hua-lin Wang; Fei Deng

    2012-01-01

    Influenza virus is a continuous and severe global threat to mankind.The continuously re-emerging disease gives rise to thousands of deaths and enormous economic losses each year,which emphasizes the urgency and necessity to develop high-quality influenza vaccines in a safer,more efficient and economic way.The influenza subunit and VLP vaccines,taking the advantage of recombinant DNA technologies and expression system platforms,can be produced in such an ideal way.This review summarized the recent advancements in the research and development of influenza subunit and VLP vaccines based on the recombinant expression of hemagglutinin antigen (HA),neuraminidase antigen (NA),Matrix 2 protein (M2) and nucleocapsid protein (NP).It would help to get insight into the current stage of influenza vaccines,and suggest the future design and development of novel influenza vaccines.

  6. Protein kinase A regulatory subunit distribution in medulloblastoma

    International Nuclear Information System (INIS)

    Previous studies showed a differential distribution of the four regulatory subunits of cAMP-dependent protein kinases inside the brain, that changed in rodent gliomas: therefore, the distribution of these proteins inside the brain can give information on the functional state of the cells. Our goal was to examine human brain tumors to provide evidence for a differential distribution of protein kinase A in different tumors. The distribution of detergent insoluble regulatory (R1 and R2) and catalytic subunits of cAMP dependent kinases was examined in pediatric brain tumors by immunohistochemistry and fluorescent cAMP analogues binding. R2 is organized in large single dots in medulloblastomas, while it has a different appearance in other tumors. Fluorescent cAMP labelling was observed only in medulloblastoma. A different distribution of cAMP dependent protein kinases has been observed in medulloblastoma

  7. Mapping of the Mouse Actin Capping Protein Beta Subunit Gene

    Directory of Open Access Journals (Sweden)

    Cooper John A

    2000-07-01

    Full Text Available Abstract Background Capping protein (CP, a heterodimer of α and β subunits, is found in all eukaryotes. CP binds to the barbed ends of actin filaments in vitro and controls actin assembly and cell motility in vivo. Vertebrates have three isoforms of CPβ produced by alternatively splicing from one gene; lower organisms have one gene and one isoform. Results We isolated genomic clones corresponding to the β subunit of mouse CP and identified its chromosomal location by interspecies backcross mapping. Conclusions The CPβ gene (Cappb1 mapped to Chromosome 4 between Cdc42 and D4Mit312. Three mouse mutations, snubnose, curly tail, and cribriform degeneration, map in the vicinity of the β gene.

  8. Peer-to-Peer Consultations: Ancillary Services Peer Exchange with India: Experience from South Africa, Europe & the United States (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2014-05-01

    In support of national and subnational decision makers, the 21st Century Power Partnership regularly works with country partners to organize peer-to-peer consultations on critical issues. In March 2014, 21CPP collaborated with the Regulatory Assistance Project - India to host two peer-to-peer exchanges among experts from India, South Africa, Europe, and the United States to discuss the provision of ancillary services, particularly in the context of added variability and uncertainty from renewable energy. This factsheet provides a high level summary of the peer-to-peer consultation.

  9. GABAB(1) receptor subunit isoforms differentially regulate stress resilience

    OpenAIRE

    O’Leary, Olivia F.; Felice, Daniela; Galimberti, Stefano; Savignac, Hélène M.; Bravo, Javier A.; Crowley, Tadhg; El Yacoubi, Malika; Vaugeois, Jean-Marie; Gassmann, Martin; Bettler, Bernhard; Dinan, Timothy G.; Cryan, John F.

    2014-01-01

    Stress can increase susceptibility to developing psychiatric disorders, including depression. Understanding the neurobiological mechanisms underlying stress resilience and susceptibility is key to identifying novel targets for the development of more effective treatments for stress-related psychiatric disorders. Here we show that specific isoforms of GABAB receptor subunits differentially regulate stress resilience. Specifically, GABAB(1a)−/− mice are more susceptible whereas GABAB(1b)−/− mic...

  10. Characterisation of connective tissue cells containing factor XIII subunit a.

    OpenAIRE

    Adány, R; Glukhova, M A; Kabakov, A Y; Muszbek, L

    1988-01-01

    Paraffin embedded sections of human liver, lymph node, and placenta showed that certain connective tissue cells were positive for factor XIII subunit a. These cells were further characterised by double immunofluorescence labelling and by combined immunofluorescence and enzyme cytochemical staining on frozen sections. They were labelled by the monoclonal antibodies RFD7 and anti-Leu M3 (markers of the macrophage cell line) but gave a negative reaction for the fibroblast marker IIG10 and showed...

  11. Ribosomal small subunit domains radiate from a central core

    Science.gov (United States)

    Gulen, Burak; Petrov, Anton S.; Okafor, C. Denise; Vander Wood, Drew; O'Neill, Eric B.; Hud, Nicholas V.; Williams, Loren Dean

    2016-02-01

    The domain architecture of a large RNA can help explain and/or predict folding, function, biogenesis and evolution. We offer a formal and general definition of an RNA domain and use that definition to experimentally characterize the rRNA of the ribosomal small subunit. Here the rRNA comprising a domain is compact, with a self-contained system of molecular interactions. A given rRNA helix or stem-loop must be allocated uniquely to a single domain. Local changes such as mutations can give domain-wide effects. Helices within a domain have interdependent orientations, stabilities and interactions. With these criteria we identify a core domain (domain A) of small subunit rRNA. Domain A acts as a hub, linking the four peripheral domains and imposing orientational and positional restraints on the other domains. Experimental characterization of isolated domain A, and mutations and truncations of it, by methods including selective 2‧OH acylation analyzed by primer extension and circular dichroism spectroscopy are consistent with our architectural model. The results support the utility of the concept of an RNA domain. Domain A, which exhibits structural similarity to tRNA, appears to be an essential core of the small ribosomal subunit.

  12. Immunological Effect of Subunit Influenza Vaccine Entrapped by Liposomes

    Institute of Scientific and Technical Information of China (English)

    SHUI-HUA ZHANG; JIA-XU LIANG; SHU-YAN DAI; XIAO-LIN QIU; YAN-RONG YI; YUN PAN

    2009-01-01

    Objective To elevate the immunological effect of subunit influenza vaccine in infants and aged people (over 60) using liposomal adjuvant in the context of its relatively low immunity and to investigate the relation between vaccine antigens and liposomal characteristics. Methods Several formulations of liposomal subunit influenza vaccine were prepared. Their relevant characteristics were investigated to optimize the preparation method. Antisera obtained from immunizinged mice were used to evaluate the antibody titers of various samples by HI and ELISA. Results Liposomal trivalent influenza vaccine prepared by film evaporation in combinedation with freeze-drying significantly increased its immunological effect in SPF Balb/c mice. Liposomal vaccine stimulated the antibody titer of H3N2, H1N1, and B much stronger than conventional influenza vaccine. As a result, liposomal vaccine (mean size: 4.5-5.5 μm, entrapment efficiency: 30%-40%) significantly increased the immunological effect of subunit influenza vaccine. Conclusion The immune effect of liposomal vaccine depends on different antigens, and enhanced immunity is not positively correlated with the mean size of liposome or its entrapped efficiency.

  13. Radioimmunoassay of TSH subunits in thyroid diseases and endocrine opthalmopahty

    International Nuclear Information System (INIS)

    Highly sensitive radioimmunoassays of hTSH sub-units were developed. The hormone preparations were labelled with 125-iodine according to a modified chloramine -T method, and purified by chromatography using biogel P6 and P60. Rabbit antisera were used as antibodies. Separation of the antibody-bound and of the free antigens was carried out via the double antibody method. The antiserum required for this purpose was obtained from a goat. The sensitivity of the assay was influenced by changing the protein content of the buffer, the incubation volume, the tracer amounts, the incubation time and the incubation temperature. For hTSH-α, the lowest detectable limit was found to be 50 pg/ml, for hTSH-#betta# 20 pg/ml. Thus, the sub-units could be determined for 98% of the patients under review. The #betta#-TSH radioimmunoassay is largely specific, TSH cross-reacts to a degree of 5%. The computerized evoluation was carried out by means of Spline approximation using the Siemens 4004 computer. Precision and accurateness are in compliance with generally accpted criteria. The serum levels of α and #betta# sub-units showed no discordancy with regard to TSH. In all groups of patients examined, the levels of the hormone-specific #betta#-chain were found to be exclusively dependent upon the actual thyroid activity. (orig.)

  14. Mutant GABA(A) receptor subunits in genetic (idiopathic) epilepsy.

    Science.gov (United States)

    Hirose, Shinichi

    2014-01-01

    The γ-aminobutyric acid receptor type A (GABAA receptor) is a ligand-gated chloride channel that mediates major inhibitory functions in the central nervous system. GABAA receptors function mainly as pentamers containing α, β, and either γ or δ subunits. A number of antiepileptic drugs have agonistic effects on GABAA receptors. Hence, dysfunctions of GABAA receptors have been postulated to play important roles in the etiology of epilepsy. In fact, mutations or genetic variations of the genes encoding the α1, α6, β2, β3, γ2, or δ subunits (GABRA1, GABRA6, GABRB2, GABRB3, GABRG2, and GABRD, respectively) have been associated with human epilepsy, both with and without febrile seizures. Epilepsy resulting from mutations is commonly one of following, genetic (idiopathic) generalized epilepsy (e.g., juvenile myoclonic epilepsy), childhood absence epilepsy, genetic epilepsy with febrile seizures, or Dravet syndrome. Recently, mutations of GABRA1, GABRB2, and GABRB3 were associated with infantile spasms and Lennox-Gastaut syndrome. These mutations compromise hyperpolarization through GABAA receptors, which is believed to cause seizures. Interestingly, most of the insufficiencies are not caused by receptor gating abnormalities, but by complex mechanisms, including endoplasmic reticulum (ER)-associated degradation, nonsense-mediated mRNA decay, intracellular trafficking defects, and ER stress. Thus, GABAA receptor subunit mutations are now thought to participate in the pathomechanisms of epilepsy, and an improved understanding of these mutations should facilitate our understanding of epilepsy and the development of new therapies. PMID:25194483

  15. Comparison of Large Subunits of Type II DNA-dependent RNA Polymerases from Higher Plants.

    Science.gov (United States)

    Kidd, G H; Link, G; Bogorad, L

    1979-10-01

    Two-dimensional tryptic mapping of (125)I-labeled polypeptides has been employed to compare the large subunits of type II DNA-dependent RNA polymerases from maize, parsley (Petroselinum sativum), and wheat. Maps of the 220 kilodalton (kd) and 140 kd subunits from wheat RNA polymerase II differ from those of the corresponding subunits from parsley enzyme II. The 180 kd subunits from maize and parsley type II enzymes also yield dissimilar tryptic maps. Thus, despite similarities in molecular mass, the large subunits of wheat, parsley, and maize type II RNA polymerases are unique to each individual plant species. PMID:16661032

  16. On the multiple roles of the voltage gated sodium channel β1 subunit in genetic diseases

    Directory of Open Access Journals (Sweden)

    Debora eBaroni

    2015-05-01

    Full Text Available Voltage-gated sodium channels are intrinsic plasma membrane proteins that initiate the action potential in electrically excitable cells. They are composed of a pore-forming α-subunit and associated β-subunits. The β1-subunit was the first accessory subunit to be cloned. It can be important for controlling cell excitability and modulating multiple aspects of sodium channel physiology. Mutations of β1 are implicated in a wide variety of inherited pathologies, including epilepsy and cardiac conduction diseases. This review summarizes β1-subunit related channelopathies pointing out the current knowledge concerning their genetic background and their underlying molecular mechanisms.

  17. Regulation of expression of a soybean storage protein subunit gene: Final report

    International Nuclear Information System (INIS)

    In an effort to determine why methionine decreases the level of the conglycinin β-subunit in cultured soybean seeds, we have established that: (1) methionine does not accelerate the degradation of the β-subunit; (2) that methionine is probably not acting by methylating the β-subunit gene; (3) that methionine is preventing the appearance of a translatable β-subunit mRNA; (4) that methionine is probably not accelerating the degradation of the β-subunit mRNA; and (5) methionine causes a marked increase in a small (0.7 kb) poly A+ RNA. 6 refs., 4 figs., 2 tabs

  18. Hybridization of glutamate aspartate transaminase. Investigation of subunit interaction.

    Science.gov (United States)

    Boettcher, B; Martinez-Carrion, M

    1975-10-01

    Glutamate aspartate transaminase (EC 2.6.1.1) is a dimeric enzyme with identical subunits with each active site containing pyridoxal 5'-phosphate linked via an internal Shiff's base to a lysine residue. It is not known if these sites interact during catalysis but negative cooperativity has been reported for binding of the coenzyme (Arrio-Dupont, M. (1972), Eur. J. Biochem. 30, 307). Also nonequivalence of its subunits in binding 8-anilinonaphthalene-1-sulfonate (Harris, H.E., and Bayley, P. M. (1975), Biochem. J. 145, 125), in modification of only a single tyrosine with full loss of activity (Christen, P., and Riordan, J.F. (1970), Biochemistry 9, 3025), and following modification with 5,5'-dithiobis(2-nitrobenzoic acid) (Cournil, I., and Arrio-Dupont, M. (1973), Biochemie 55, 103) has been reported. However, steady-state and transient kinetic methods as well as direct titration of the active site chromophore with substrates and substrate analogs have not revealed any cooperative phenomena (Braunstein, A. E. (1973), Enzymes, 3rd Ed. 9, 379). It was therefore decided that a more direct approach should be used to clarify the quistion of subunit interaction during the covalent phase of catalysis. To this end a hybrid method was devised in which a hybrid transaminase was prepared which contained one subunit with a functional active site while the other subunit has the internal Shiff's base reduced with NaBH4. The specific activities and amount of "actively bound" pyridoxal 5'-phosphate are both in a 2:1 ratio for the native and hybrid forms. Comparison of the steady-state kinetic properties of the hybrid and native enzyme forms shows that both forms gave parallel double reciprocal plots which is characteristic of the Ping-Pong Bi-Bi mechanism of transamination. The Km values for the substrates L-aspartic acid and alpha-ketoglutaric acid are nearly identical while the Vmax value for the hybrid is one-half the value of the native transaminase. It therefore appears that

  19. Radioimmunoassay for determination of alpha subunit of pituitary glycoprotein hormones in patients with pituitary tumors

    International Nuclear Information System (INIS)

    A radioimmunoassay method for alpha subunit has been described and applied for serum alpha subunit determinations in normal subjects and 71 patients with pituitary tumors /45 acromegalic and 26 non-acromegalic/. The labelling of alpha subunit by the chloramine T technique yielded 125I-alpha subunit of high specific activity and high immuno-reactivity. Three purification methods of labelled 125I-alpha subunit were compared; the best separation of undamaged 125I-alpha subunit from impurities was achieved by gel filtration on Ultrogel AcA54 column, whereas gel filtration on Sephadex G-100 and adsorption chromatography on CF-11 cellulose gave less satisfactory results. Microheterogenity of 125I-alpha subunit was disclosed by chromatofocusing on PBE 94; the fractions of high immunoreactivitiy had isoelectric points of 6.0, 5.5 and 4.8. In normal subjects, radioimmunoassay of alpha subunit gave the following results /mean and SD/: 0.75 ng/ml +- 0.41 in males and 0.80 ng/ml +- 0.39 in females in reproductive age. In 9 acromegalic serum alpha subunit concentration were elevated up to 21 ng/ml, and in 8 non-acromegalic up to 30 ng/ml. One woman with acromegaly and high serum alpha subunit concentration had also elevated serum TSH associated with hyperthyroids. Our results disclosed that high serum alpha subunit concentration occurs in 25 % of patients with pituitary adenomas. (Author)

  20. Structure of subcomplex Iβ of mammalian respiratory complex I leads to new supernumerary subunit assignments.

    Science.gov (United States)

    Zhu, Jiapeng; King, Martin S; Yu, Minmin; Klipcan, Liron; Leslie, Andrew G W; Hirst, Judy

    2015-09-29

    Mitochondrial complex I (proton-pumping NADH:ubiquinone oxidoreductase) is an essential respiratory enzyme. Mammalian complex I contains 45 subunits: 14 conserved "core" subunits and 31 "supernumerary" subunits. The structure of Bos taurus complex I, determined to 5-Å resolution by electron cryomicroscopy, described the structure of the mammalian core enzyme and allowed the assignment of 14 supernumerary subunits. Here, we describe the 6.8-Å resolution X-ray crystallography structure of subcomplex Iβ, a large portion of the membrane domain of B. taurus complex I that contains two core subunits and a cohort of supernumerary subunits. By comparing the structures and composition of subcomplex Iβ and complex I, supported by comparisons with Yarrowia lipolytica complex I, we propose assignments for eight further supernumerary subunits in the structure. Our new assignments include two CHCH-domain containing subunits that contain disulfide bridges between CX9C motifs; they are processed by the Mia40 oxidative-folding pathway in the intermembrane space and probably stabilize the membrane domain. We also assign subunit B22, an LYR protein, to the matrix face of the membrane domain. We reveal that subunit B22 anchors an acyl carrier protein (ACP) to the complex, replicating the LYR protein-ACP structural module that was identified previously in the hydrophilic domain. Thus, we significantly extend knowledge of how the mammalian supernumerary subunits are arranged around the core enzyme, and provide insights into their roles in biogenesis and regulation. PMID:26371297

  1. Generalized epilepsy with febrile seizures plus-associated sodium channel beta1 subunit mutations severely reduce beta subunit-mediated modulation of sodium channel function.

    Science.gov (United States)

    Xu, R; Thomas, E A; Gazina, E V; Richards, K L; Quick, M; Wallace, R H; Harkin, L A; Heron, S E; Berkovic, S F; Scheffer, I E; Mulley, J C; Petrou, S

    2007-08-10

    Two novel mutations (R85C and R85H) on the extracellular immunoglobulin-like domain of the sodium channel beta1 subunit have been identified in individuals from two families with generalized epilepsy with febrile seizures plus (GEFS+). The functional consequences of these two mutations were determined by co-expression of the human brain NaV1.2 alpha subunit with wild type or mutant beta1 subunits in human embryonic kidney (HEK)-293T cells. Patch clamp studies confirmed the regulatory role of beta1 in that relative to NaV1.2 alone the NaV1.2+beta1 currents had right-shifted voltage dependence of activation, fast and slow inactivation and reduced use dependence. In addition, the NaV1.2+beta1 current entered fast inactivation slightly faster than NaV1.2 channels alone. The beta1(R85C) subunit appears to be a complete loss of function in that none of the modulating effects of the wild type beta1 were observed when it was co-expressed with NaV1.2. Interestingly, the beta1(R85H) subunit also failed to modulate fast kinetics, however, it shifted the voltage dependence of steady state slow inactivation in the same way as the wild type beta1 subunit. Immunohistochemical studies revealed cell surface expression of the wild type beta1 subunit and undetectable levels of cell surface expression for both mutants. The functional studies suggest association of the beta1(R85H) subunit with the alpha subunit where its influence is limited to modulating steady state slow inactivation. In summary, the mutant beta1 subunits essentially fail to modulate alpha subunits which could increase neuronal excitability and underlie GEFS+ pathogenesis. PMID:17629415

  2. Allotopic Expression of a Gene Encoding FLAG Tagged-subunit 8 of Yeast Mitochondrial ATP Synthase

    Directory of Open Access Journals (Sweden)

    I MADE ARTIKA

    2006-03-01

    Full Text Available Subunit 8 of yeast mitochondrial ATP synthase is a polypeptide of 48 amino acids encoded by the mitochondrial ATP8 gene. A nuclear version of subunit 8 gene has been designed to encode FLAG tagged-subunit 8 fused with a mitochondrial signal peptide. The gene has been cloned into a yeast expression vector and then expressed in a yeast strain lacking endogenous subunit 8. Results showed that the gene was successfully expressed and the synthesized FLAG tagged-subunit 8 protein was imported into mitochondria. Following import, the FLAG tagged-subunit 8 protein assembled into functional mitochondrial ATP synthase complex. Furthermore, the subunit 8 protein could be detected using anti-FLAG tag monoclonal antibody.

  3. Distinct conformational changes in activated agonist-bound and agonist-free glycine receptor subunits

    DEFF Research Database (Denmark)

    Pless, Stephan Alexander; Lynch, Joseph W

    2009-01-01

    glycine-free or a glycine-bound subunit. Agonist-free subunits were created by incorporating T204A and R65K mutations, which disrupted glycine binding to both (+) and (-) subunit interfaces. In heteromeric receptors comprising wild-type and R65K,T204A,R271C triple-mutant subunits, the fluorescence...... response exhibited a drastically reduced glycine sensitivity relative to the current response. Two conclusions can be drawn from this. First, because the labeled glycine-free subunits were activated by glycine binding to neighboring wild-type subunits, our results provide evidence for a cooperative...... activation mechanism. However, because the fluorescent label on glycine-free subunits does not reflect movements at the channel gate, we conclude that glycine binding also produces a local non-concerted conformational change that is not essential for receptor activation....

  4. Functional Diversification of Maize RNA Polymerase IV and V subtypes via Alternative Catalytic Subunits

    Energy Technology Data Exchange (ETDEWEB)

    Haag, Jeremy R.; Brower-Toland, Brent; Krieger, Elysia K.; Sidorenko, Lyudmila; Nicora, Carrie D.; Norbeck, Angela D.; Irsigler, Andre; LaRue, Huachun; Brzeski, Jan; Mcginnis, Karen A.; Ivashuta, Sergey; Pasa-Tolic, Ljiljana; Chandler, Vicki L.; Pikaard, Craig S.

    2014-10-01

    Unlike nuclear multisubunit RNA polymerases I, II, and III, whose subunit compositions are conserved throughout eukaryotes, plant RNA polymerases IV and V are nonessential, Pol II-related enzymes whose subunit compositions are still evolving. Whereas Arabidopsis Pols IV and V differ from Pol II in four or five of their 12 subunits, respectively, and differ from one another in three subunits, proteomic ana- lyses show that maize Pols IV and V differ from Pol II in six subunits but differ from each other only in their largest subunits. Use of alternative catalytic second subunits, which are nonredundant for development and paramutation, yields at least two sub- types of Pol IV and three subtypes of Pol V in maize. Pol IV/Pol V associations with MOP1, RMR1, AGO121, Zm_DRD1/CHR127, SHH2a, and SHH2b extend parallels between paramutation in maize and the RNA-directed DNA methylation pathway in Arabidopsis.

  5. Isolation and characterization of recombinant human casein kinase II subunits alpha and beta from bacteria

    DEFF Research Database (Denmark)

    Grankowski, N; Boldyreff, B; Issinger, O G

    1991-01-01

    cDNA encoding the casein kinase II (CKII) subunits alpha and beta of human origin were expressed in Escherichia coli using expression vector pT7-7. Significant expression was obtained with E. coli BL21(DE3). The CKII subunits accounted for approximately 30% of the bacterial protein; however, most...... of the expressed proteins were produced in an insoluble form. The recombinant CKII alpha subunit was purified by DEAE-cellulose chromatography, followed by phosphocellulose and heparin-agarose chromatography. The recombinant CKII beta subunit was extracted from the insoluble pellet and purified in a...... single step on phosphocellulose. From 10 g bacterial cells, the yield of soluble protein was 12 mg alpha subunit and 5 mg beta subunit. SDS/PAGE analysis of the purified recombinant proteins indicated molecular masses of 42 kDa and 26 kDa for the alpha and beta subunits, respectively, in agreement with...

  6. Mesenteric vascular occlusion: Comparison of ancillary CT findings between arterial and venous occlusions and independent CT findings suggesting life-threatening events

    International Nuclear Information System (INIS)

    To compare the ancillary CT findings between superior mesenteric artery thromboembolism (SMAT) and superior mesenteric vein thrombosis (SMVT), and to determine the independent CT findings of life-threatening mesenteric occlusion. Our study was approved by the institution review board. We included 43 patients (21 SMAT and 22 SMVT between 1999 and 2008) of their median age of 60.0 years, and retrospectively analyzed their CT scans. Medical records were reviewed for demographics, management, surgical pathology diagnosis, and outcome. We compared CT findings between SMAT and SMVT groups. Multivariate analysis was conducted to determine the independent CT findings of life-threatening mesenteric occlusion. Of 43 patients, 24 had life-threatening mesenteric occlusion. Death related to mesenteric occlusion was 32.6%. A thick bowel wall (p < 0.001), mesenteric edema (p < 0.001), and ascites (p = 0.009) were more frequently associated with SMVT, whereas diminished bowel enhancement (p = 0.003) and paralytic ileus (p = 0.039) were more frequent in SMAT. Diminished bowel enhancement (OR = 20; p = 0.007) and paralytic ileus (OR = 16; p = 0.033) were independent findings suggesting life-threatening mesenteric occlusion. The ancillary CT findings occur with different frequencies in SMAT and SMVT. However, the independent findings indicating life-threatening mesenteric occlusion are diminished bowel wall enhancement and paralytic ileus.

  7. Vehicle Ancillary Load Reduction Project Close-Out Report: An Overview of the Task and a Compilation of the Research Results

    Energy Technology Data Exchange (ETDEWEB)

    Rugh, J.; Farrington, R.

    2008-01-01

    The amount of fuel used for climate control in U.S. vehicles reduces the fuel economy of more than 200 million light-duty conventional vehicles and thus affects U.S. energy security. Researchers at the DOE National Renewable Energy Laboratory estimated that the United States consumes about 7 billion gallons of fuel per year for air-conditioning (A/C) light-duty vehicles. Using a variety of tools, NREL researchers developed innovative techniques and technologies to reduce the amount of fuel needed for these vehicles' ancillary loads. For example, they found that the A/C cooling capacity of 5.7 kW in a Cadillac STS could be reduced by 30% while maintaining a cooldown performance of 30 minutes. A simulation showed that reducing the A/C load by 30% decreased A/C fuel consumption by 26%. Other simulations supported the great potential for improving fuel economy by using new technologies and techniques developed to reduce ancillary loads.

  8. Compliance with technical codes becomes obligatory for receipt of feed-in tariff and ancillary services bonus for wind power plants in Germany

    Energy Technology Data Exchange (ETDEWEB)

    Boemer, Jens. C. [Ecofys Germany GmbH, Berlin (Germany). Power Systems and Markets Group; Delft Univ. of Technology (Netherlands). Electrical Power Systems Group; Burges, Karsten [Ecofys Germany GmbH, Berlin (Germany). Power Systems and Markets Group; Kumm, Thomas [VDE, Network Technology and Operation Forum (FNN), Berlin (Germany); Poeller, Markus [DIgSILENT GmbH, Gomaringen (Germany)

    2009-07-01

    The German government aims at a share of electricity generation based on renewable sources (RES-E) of more than 30% by 2020. A major part of this share will be reached by the use of wind power plants (WPP). Therefore, when amending the Renewable Energy Sources Act (EEG) in June 2008, the German government acknowledged the importance of enhanced technical requirements for WPP and announced the development of a respective technical ordinance. For all WPP that go into operation after June 2010, full grid code-compliance becomes a precondition for privileged network access, receipt of feed-in tariff, and extra payments (''ancillary services bonus''). The basis for the technical requirements in the EEG has been laid down by Medium-Voltage (MV)-Directive 2008 and the TransmissionCode 2007. However, the work of the authors - consulting the German government during the development of the technical ordinance - showed that the TransmissionCode 2007 needed careful review and some clarifying specifications were proposed. Eventually, the so called ''Ancillary Services Ordinance'' for wind power plants went into power in July 2009. The interrelation between all three grid codes as well as their specifications and implications for renewable energy sources generators, with special regard to wind power plants, are presented in this paper. (orig.)

  9. Transperineal bulboprostatic anastomotic repair of pelvic fracture urethral distraction defect and role of ancillary maneuver: A retrospective study in 172 patients

    Directory of Open Access Journals (Sweden)

    Singh Santosh

    2010-01-01

    Full Text Available Objective: We present our experience with transperineal bulboprostatic anastomosis procedure and compare the results with age of patients, length of urethral stricture, effect of previous treatment and need for ancillary procedures. Materials and Methods: We retrospectively reviewed the outcome of 172 patients who underwent perineal urethroplasty procedure for traumatic stricture in our institute. Simple perineal anastomosis was done in 92 patients. Perineal anastomosis and corporal separation were done in 52 patients. Perineal anastomosis with inferior pubectomy was done in 25 patients. Perineal anastomosis with rerouting was done in three patients. Age, prior treatment, length of stricture, and ancillary techniques required during reconstruction were compiled. The clinical outcome was considered as failure when any postoperative instrumentation was needed. Results: Out of 172 cases that underwent transperineal urethroplasty procedure, 157 (91.28% were successful. Simple perineal urethroplasty procedure showed a success rate of 93.4%, perineal anastomosis with separation of corporal bodies had a success rate of 90.4%, perineal anastomosis with inferior pubectomy had a success rate of 88% and perineal anastomosis with rerouting of urethra around the corpora had a success rate of 66.7%. Conclusion: The success rate of delayed progressive perineal urethroplasty procedure for post-traumatic stricture urethra is excellent and majority of the failures occurs in prepubescent boys and in those undergoing secondary repair.

  10. Hypersecretion of the alpha-subunit in clinically non-functioning pituitary adenomas: Diagnostic accuracy is improved by adding alpha-subunit/gonadotropin ratio to levels of alpha-subunit

    DEFF Research Database (Denmark)

    Andersen, Marianne; Ganc-Petersen, Joanna; Jørgensen, Jens Otto Lunde;

    2010-01-01

    when the alpha-ratios, rather than simply the alpha-subunit levels, were measured in patients with NFPAs. MATERIAL AND METHODS: Reference intervals for gonadotropin alpha-subunit serum levels and alpha-ratios were established in 231 healthy adults. The estimated cut-off limits were applied to 37...... patients with NFPAs. Gonadotropin alpha-subunit, LH and FSH levels were measured and alpha-ratios were calculated. RESULTS: In healthy adults, the cut-offs for alpha-subunit levels were significantly different between men and pre- and postmenopausal women: the cut-offs were 1.10, 0.48 and 3.76 IU....../l, respectively. Using these estimated cut-offs, increased alpha-subunit levels were identified in 10 out of 37 (27%) patients with NFPAs. By adding alpha-ratio, in combination with alpha-subunit levels, 23 patients out of 37 (62%) were identified as having elevated alpha-subunit hypersecretion, and 22 out of...

  11. Covalent dimerization of ribulose bisphosphate carboxylase subunits by UV radiation

    International Nuclear Information System (INIS)

    The effect of UV radiation (UV-A, UV-B and UV-C) on ribulose bisphosphate carboxylase from a variety of plant species was examined. The exposition of plant leaves or the pure enzyme to UV radiation produced a UV-dependent accumulation of a 65 kDa polypeptide (P65). Different approaches were utilized to elucidate the origin and structure of P65: electrophoretic and fluorographic analyses of 35S-labelled ribulose biphosphate carboxylase exposed to UV radiation and immunological experiments using antibodies specific for P65, for the large and small subunits of ribulose biphosphate carboxylase and for high-molecular-mass aggregates of the enzyme. These studies revealed that P65 is a dimer, formed by the covalent, non-disulphide linkage of one small subunit with one large subunit of ribulose biphosphate carboxylase. For short periods of time (<1 h), the amount of P65 formed increased with the duration of the exposure to the UV radiation and with the energy of the radiation applied. Prolonged exposure to UV radiation (1-6 h) resulted in the formation of high-molecular-mass aggregates of ribulose biphosphate carboxylase. Formation of P65 was shown to depend on the native state of the protein, was stimulated by inhibitors of enzyme activity, and was inhibited by activators of enzyme activity. A UV-independent accumulation of P65 was also achieved by the in vitro incubation of plant crude extracts. However, the UV-dependent and the UV-independent formation of P65 seemed to occur by distinct molecular mechanisms. The UV-dependent accumulation of P65 was immunologically detected in all species examined, including Lemna minor, Arum italicum, Brassica oleracea, Triticum aestivum, Zea mays, Pisum sativum and Phaseolus vulgaris, suggesting that it may constitute a universal response to UV radiation, common to all photosynthetic tissues. (Author)

  12. Characterisation of the tryptophan synthase alpha subunit in maize

    Directory of Open Access Journals (Sweden)

    Gierl Alfons

    2008-04-01

    Full Text Available Abstract Background In bacteria, such as Salmonella typhimurium, tryptophan is synthesized from indole-3-glycerole phosphate (IGP by a tryptophan synthase αββα heterotetramer. Plants have evolved multiple α (TSA and β (TSB homologs, which have probably diverged in biological function and their ability of subunit interaction. There is some evidence for a tryptophan synthase (TS complex in Arabidopsis. On the other hand maize (Zea mays expresses the TSA-homologs BX1 and IGL that efficiently cleave IGP, independent of interaction with TSB. Results In order to clarify, how tryptophan is synthesized in maize, two TSA homologs, hitherto uncharacterized ZmTSA and ZmTSAlike, were functionally analyzed. ZmTSA is localized in plastids, the major site of tryptophan biosynthesis in plants. It catalyzes the tryptophan synthase α-reaction (cleavage of IGP, and forms a tryptophan synthase complex with ZmTSB1 in vitro. The catalytic efficiency of the α-reaction is strongly enhanced upon complex formation. A 160 kD tryptophan synthase complex was partially purified from maize leaves and ZmTSA was identified as native α-subunit of this complex by mass spectrometry. ZmTSAlike, for which no in vitro activity was detected, is localized in the cytosol. ZmTSAlike, BX1, and IGL were not detectable in the native tryptophan synthase complex in leaves. Conclusion It was demonstrated in vivo and in vitro that maize forms a tryptophan synthase complex and ZmTSA functions as α-subunit in this complex.

  13. Thermostable Subunit Vaccines for Pulmonary Delivery: How Close Are We?

    Science.gov (United States)

    Foged, Camilla

    2016-01-01

    In the past century, vaccines have contributed to a significant improvement in global public health by preventing a number of infectious diseases. Despite this, the vaccine field is still facing challenges related to incomplete vaccine coverage and persistent difficult vaccine targets, such as influenza, tuberculosis, and Ebola, for which no good universal vaccines exist. At least two pharmaceutical improvements are expected to help filling this gap: i) The development of thermostable vaccine dosage forms, and ii) the full exploitation of the adjuvant technology for subunit vaccines to potentiate strong immune responses. This review highlights the status and recent advances in formulation and pulmonary delivery of thermostable human subunit vaccines. Such vaccines are very appealing from compliance, distribution and immunological point of view: Being non-invasive, inhalable vaccines are self-administrable, can be distributed independently of functioning freezers and refrigerators, and can be designed to induce mucosal and/or cell-mediated immunity, which is attractive for a number of diseases requiring stimulation of local mucosal immunity for protection. However, the design and delivery of thermostable dry powder-based vaccines represents a technological challenge: It calls for careful formulation and dosage form design, combined with cheap and efficient delivery devices, which must be engineered via a thorough understanding of the physiological barrier and the requirements for induction of mucosal immunity. Here, I review state of the art and perspectives in formulation design and processing methods for powder-based subunit vaccines intended for pulmonary administration, and present dry powder inhaler technologies suitable for translating these vaccines into clinical trials. PMID:26831645

  14. Molecular cloning of the human casein kinase II α subunit

    International Nuclear Information System (INIS)

    A human cDNA encoding the α subunit of casein kinase II and a partial cDNA encoding the rat homologue were isolated by using a Drosophila casein kinase II cDNA probe. The 2.2-kb human cDNA contains a 1.2-kb open reading frame, 150 nucleotides of 5' leader, and 850 nucleotides of 3' noncoding region. Except for the first 7 deduced amino acids that are missing in the rat cDNA, the 328 amino acids beginning with the amino terminus are identical between human and rat. The Drosophila enzyme sequence is 90% identical with the human casein kinase II sequence, and there is only a single amino acid difference between the published partial bovine sequence and the human sequence. In addition, the C-terminus of the human cDNA has an extra 53 amino acids not present in Drosophila. Northern analysis of rat and human RNA showed predominant bands of 5.5, 3.1, and 1.8 kb. In rat tissues, brain and spleen had the highest levels of casein kinase II α subunit specific RNA, while skeletal muscle showed the lowest. Southern analysis of human cultured cell and tissue genomic DNA using the full-length cDNA probe revealed two bands with restriction enzymes that have no recognition sites within the cDNA and three to six bands with enzymes having single internal sites. These results are consistent with the possibility that two genes encode the α subunits

  15. Covalent dimerization of ribulose bisphosphate carboxylase subunits by UV radiation

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, R.M.B. [Universidade Tecnica, Lisbon (Portugal). Inst. Superior de Agronomia]|[Universidade Nova de Lisboa, Oeiras (Portugal). Instituto de Tecnologia Quimica e Biologica; Franco, E.; Teixeira, A.R.N. [Universidade Tecnica, Lisbon (Portugal). Inst. Superior de Agronomia

    1996-08-15

    The effect of UV radiation (UV-A, UV-B and UV-C) on ribulose bisphosphate carboxylase from a variety of plant species was examined. The exposition of plant leaves or the pure enzyme to UV radiation produced a UV-dependent accumulation of a 65 kDa polypeptide (P65). Different approaches were utilized to elucidate the origin and structure of P65: electrophoretic and fluorographic analyses of {sup 35}S-labelled ribulose biphosphate carboxylase exposed to UV radiation and immunological experiments using antibodies specific for P65, for the large and small subunits of ribulose biphosphate carboxylase and for high-molecular-mass aggregates of the enzyme. These studies revealed that P65 is a dimer, formed by the covalent, non-disulphide linkage of one small subunit with one large subunit of ribulose biphosphate carboxylase. For short periods of time (<1 h), the amount of P65 formed increased with the duration of the exposure to the UV radiation and with the energy of the radiation applied. Prolonged exposure to UV radiation (1-6 h) resulted in the formation of high-molecular-mass aggregates of ribulose biphosphate carboxylase. Formation of P65 was shown to depend on the native state of the protein, was stimulated by inhibitors of enzyme activity, and was inhibited by activators of enzyme activity. A UV-independent accumulation of P65 was also achieved by the in vitro incubation of plant crude extracts. However, the UV-dependent and the UV-independent formation of P65 seemed to occur by distinct molecular mechanisms. The UV-dependent accumulation of P65 was immunologically detected in all species examined, including Lemna minor, Arum italicum, Brassica oleracea, Triticum aestivum, Zea mays, Pisum sativum and Phaseolus vulgaris, suggesting that it may constitute a universal response to UV radiation, common to all photosynthetic tissues. (Author).

  16. Testing experimental subunit furunculosis vaccines for rainbow trout

    DEFF Research Database (Denmark)

    Marana, Moonika H.; Chettri, Jiwan Kumar; Skov, Jakob;

    2016-01-01

    Aeromonas salmonicida subsp. salmonicida (AS) is the etiological agent of typical furunculosis in salmonid fish. The disease causes bacterial septicemia and is a major fish health problem in salmonid aquaculture worldwide, inducing high morbidity and mortality. In this study we vaccinated rainbow...... response against AS. Fourteen proteins were prepared in 3 different experimental subunit vaccine combinations and used to vaccinate rainbow trout by intraperitoneal (i.p.) injection. We tested the proteins for their ability to elicit antibody production and protection. Thus, fish were exposed to virulent...

  17. Smallpox subunit vaccine produced in planta confers protection in mice

    OpenAIRE

    Golovkin, Maxim; Spitsin, Sergei; Andrianov, Vyacheslav; Smirnov, Yuriy; Xiao, Yuhong; Pogrebnyak, Natalia; Markley, Karen; Brodzik, Robert; Gleba, Yuri; Isaacs, Stuart N.; Koprowski, Hilary

    2007-01-01

    We report here the in planta production of the recombinant vaccinia virus B5 antigenic domain (pB5), an attractive component of a subunit vaccine against smallpox. The antigenic domain was expressed by using efficient transient and constitutive plant expression systems and tested by various immunization routes in two animal models. Whereas oral administration in mice or the minipig with collard-derived insoluble pB5 did not generate an anti-B5 immune response, intranasal administration of sol...

  18. Posttranslational modifications in the CP43 subunit of photosystem II

    OpenAIRE

    Anderson, Lorraine B.; Maderia, Melissa; Ouellette, Anthony J. A.; Putnam-Evans, Cindy; Higgins, LeeAnn; Krick, Thomas; MacCoss, Michael J; Lim, Hanjo; Yates, John R.; Barry, Bridgette A.

    2002-01-01

    Photosystem II (PSII) catalyzes the light-driven oxidation of water and the reduction of plastoquinone; the oxidation of water occurs at a cluster of four manganese. The PSII CP43 subunit functions in light harvesting, and mutations in the fifth luminal loop (E) of CP43 have established its importance in PSII structure and/or assembly [Kuhn, M. G. & Vermaas, V. F. J. (1993) Plant Mol. Biol. 23, 123–133]. The sequence A350PWLEPLR357 in luminal loop E is conserved in CP43 genes from 50 organism...

  19. Role of the beta subunit of casein kinase-2 on the stability and specificity of the recombinant reconstituted holoenzyme

    DEFF Research Database (Denmark)

    Meggio, F; Boldyreff, B; Marin, O; Pinna, L A; Issinger, O G

    1992-01-01

    Recombinant human alpha subunit from casein kinase-2 (CK-2) was subjected, either alone or in combination with recombinant human beta subunit, to high temperature, tryptic digestion and urea treatment. In all three cases, it was shown that the presence of the beta subunit could drastically reduce...... the loss of kinase activity, strongly suggesting a protective function for the beta subunit. Assaying different peptides for specificity toward the recombinant alpha subunit and the recombinant reconstituted enzyme, showed that the presence of the beta subunit could modify the specificity of the...... catalytic alpha subunit. Therefore, a dual function for the beta subunit is proposed which confers both specificity and stability to the catalytic alpha subunit within the CK-2 holoenzyme complex. The peptide DLEPDEELEDNPNQSDL, reproducing the highly acidic amino acid 55-71 segment of the human beta subunit...

  20. A charged residue at the subunit interface of PCNA promotes trimer formation by destabilizing alternate subunit interactions

    International Nuclear Information System (INIS)

    Eukaryotic proliferating cell nuclear antigen (PCNA), an essential accessory factor in DNA replication and repair, is a ring-shaped homotrimer. A novel nontrimeric structure of E113G-mutant PCNA protein is reported, which shows that this protein forms alternate subunit interactions. It is concluded that the charged side chain of Glu113 promotes normal trimer formation by destabilizing these alternate subunit interactions. Eukaryotic proliferating cell nuclear antigen (PCNA) is an essential replication accessory factor that interacts with a variety of proteins involved in DNA replication and repair. Each monomer of PCNA has an N-terminal domain A and a C-terminal domain B. In the structure of the wild-type PCNA protein, domain A of one monomer interacts with domain B of a neighboring monomer to form a ring-shaped trimer. Glu113 is a conserved residue at the subunit interface in domain A. Two distinct X-ray crystal structures have been determined of a mutant form of PCNA with a substitution at this position (E113G) that has previously been studied because of its effect on translesion synthesis. The first structure was the expected ring-shaped trimer. The second structure was an unanticipated nontrimeric form of the protein. In this nontrimeric form, domain A of one PCNA monomer interacts with domain A of a neighboring monomer, while domain B of this monomer interacts with domain B of a different neighboring monomer. The B–B interface is stabilized by an antiparallel β-sheet and appears to be structurally similar to the A–B interface observed in the trimeric form of PCNA. The A–A interface, in contrast, is primarily stabilized by hydrophobic interactions. Because the E113G substitution is located on this hydrophobic surface, the A–A interface should be less favorable in the case of the wild-type protein. This suggests that the side chain of Glu113 promotes trimer formation by destabilizing these possible alternate subunit interactions

  1. IMMUNOLOGICAL RESPONSE IN BOVINE LYMPH NODES STIMULATED WITH SUBUNITS VACCINES

    Directory of Open Access Journals (Sweden)

    Gabriel Andres Tafur Gomez

    2013-01-01

    Full Text Available The vaccination process belongs to the public health intervention methodologies that help prevent infections. Vaccinations performed successfully in the history of medicine reported the significance of this procedure to increase the quality of life, prevent zoonoses and improve animal production. Vaccine emergence remained without exact rules for a long time, maintaining a close relationship with pathogens. However, subunit vaccines, with a difference from the classical idea of protective immunity with microorganisms showed it is possible to trigger T-dependent responses with peptide, revealing new rules for vaccine development. This vaccination process starts by the modulation chance of adaptive immune response through peptide sequences process by APCs for immune synapse formation interceded for pMHC-TCR as a scaffold to T cells priming. In this way the immunological signal triggered by immune synapses is amplified in lymph nodes. As a consequence, T and B cells modulated by peptide activity interact between the B cell follicles region and T cell aggregates, which constitute the paracortical region of secondary lymphoid tissue to form connate unions as a prerequisite for clonal amplification and subsequent immunological memory. Indicating the knowledge of the mechanisms of immune response generated by peptides immunization is essential for understanding modulation, amplification and immune protection as demands for good subunits vaccine.

  2. The right to arrange ancillary services in line with municipal awards of concession; Das Recht auf Vereinbarung von Nebenleistungen im Rahmen gemeindlicher Konzessionsvergaben

    Energy Technology Data Exchange (ETDEWEB)

    Templin, Wolf [Boos Hummel und Wegerich Rechtsanwaelte, Berlin (Germany)

    2012-12-15

    Due to the plurality of concession contracts currently levelling off in the fields of electricity and natural gas as well as due to the increasing competition for the power distribution systems, the municipal granting of concession contracts as well as the relevant standards come in the focus of the legal disputes. Recently, the increasing competition and the claims of sustainable impacts of the municipalities on the local energy policy also in line with the awarding of concessions have led to the use of concession contracts for the control of local government concerns and climate political concerns of the municipalities. Under this aspect, the author of the contribution under consideration report on the right to arrange ancillary services in line with municipal awards of concession.

  3. CHRISGAS Project. WP13: Ancillary and Novel Processes. Final Report: Separation of Hydrogen with Membranes Combined with Water Gas Shift Reaction

    International Nuclear Information System (INIS)

    Oxygen pressurized gasification of biomass out stands as a very promising approach to obtain energy or hydrogen from renewable sources. The technical feasibility of this technology has been investigated under the scope of the VI FP CHRISGAS project, which started in September 2004 and had a duration of five and a half years. The Division of Combustion and Gasification of CIEMAT participated in this project in Work Package 13: Ancillary and novel processes, studying innovative gas separation and gas upgrading systems. Such systems include novel or available high temperature water gas shift catalysts and commercially available membranes not yet tried in this type of atmosphere. This report describes the activities carried out during the project regarding the performance of high temperature water gas shift catalysts for upgrading of synthesis gas obtained from biomass gasification, the separation of H2 with selective membranes and the combination of both processes in one by means of a catalytic membrane reactor. (Author) 20 refs.

  4. CHRISGAS Project. WP13: Ancillary and Novel Processes. Final Report: Separation of Hydrogen with Membranes Combined with Water Gas Shift Reaction

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez-Hervas, J. M.; Marono, M.; Barreiro, M. M.

    2011-05-13

    Oxygen pressurized gasification of biomass out stands as a very promising approach to obtain energy or hydrogen from renewable sources. The technical feasibility of this technology has been investigated under the scope of the VI FP CHRISGAS project, which started in September 2004 and had a duration of five and a half years. The Division of Combustion and Gasification of CIEMAT participated in this project in Work Package 13: Ancillary and novel processes, studying innovative gas separation and gas upgrading systems. Such systems include novel or available high temperature water gas shift catalysts and commercially available membranes not yet tried in this type of atmosphere. This report describes the activities carried out during the project regarding the performance of high temperature water gas shift catalysts for upgrading of synthesis gas obtained from biomass gasification, the separation of H2 with selective membranes and the combination of both processes in one by means of a catalytic membrane reactor. (Author) 20 refs.

  5. Ancillary therapies to enhance success of non-invasive modes of respiratory support - Approaches to delivery room use of surfactant and caffeine?

    Science.gov (United States)

    Kribs, Angela; Hummler, Helmut

    2016-06-01

    During recent decades, non-invasive respiratory support has become popular for treating neonates with respiratory failure. Several prospective randomized controlled trials have been performed to compare use of continuous positive airway pressure (CPAP) as primary respiratory support in preterm infants with respiratory distress syndrome (RDS) to endotracheal intubation, mechanical ventilation and surfactant therapy. Systematic reviews of these studies suggest that routine CPAP at delivery is efficacious in decreasing bronchopulmonary dysplasia (BPD), death, or both. This led to the recommendation to consider CPAP to avoid endotracheal intubation. As surfactant therapy is known to reduce BPD and death, several ways to combine CPAP with surfactant have been described. With the increasing use of CPAP immediately after birth, the early use of caffeine to stimulate respiration has become a point of discussion. This review focuses on different modes of surfactant application during CPAP and on the early use of caffeine as ancillary therapies to enhance CPAP success. PMID:26936187

  6. Localized reconstruction of subunits from electron cryomicroscopy images of macromolecular complexes

    OpenAIRE

    Ilca, Serban L.; Kotecha, Abhay; Sun, Xiaoyu; Poranen, Minna M; Stuart, David I.; Huiskonen, Juha T.

    2015-01-01

    Electron cryomicroscopy can yield near-atomic resolution structures of highly ordered macromolecular complexes. Often however some subunits bind in a flexible manner, have different symmetry from the rest of the complex, or are present in sub-stoichiometric amounts, limiting the attainable resolution. Here we report a general method for the localized three-dimensional reconstruction of such subunits. After determining the particle orientations, local areas corresponding to the subunits can be...

  7. Functional consequences of Kir2.1/Kir2.2 subunit heteromerization

    OpenAIRE

    Panama, Brian K.; McLerie, Meredith; Lopatin, Anatoli N.

    2010-01-01

    Kir2 subunits form channels that underlie classical strongly inwardly rectifying potassium currents. While homomeric Kir2 channels display a number of distinct and physiologically important properties, the functional properties of heteromeric Kir2 assemblies, as well as the stoichiometries and the arrangements of Kir2 subunits in native channels, remain largely unknown. Therefore, we have implemented a concatemeric approach, whereby all four cloned Kir2 subunits were linked in tandem, in orde...

  8. Beta-Subunit of Human Chorionic Gonadotropin in Malignant Lymphoma : An Immunohistochemical Study

    OpenAIRE

    Senba, Masachika; Watanabe, Masami

    1991-01-01

    We present a rare case of a 77-year-old Japanese man with malignant lymphoma associated with production of beta-subunit of human chorionic gonadotropin in the cytoplasms of lymphoma cells in the lymph nodes. By immunoperoxidase staining, numerous tumor cells were reacted with beta-subunit of human chorionic gonadotropin. To the best of our knowledge, production of beta-subunit of human chorionic gonadotropin in the cytoplasm of lymphoma cells has not been reported. This patient evidences that...

  9. The NMDA receptor NR2A subunit regulates proliferation of MKN45 human gastric cancer cells.

    Science.gov (United States)

    Watanabe, Kanako; Kanno, Takeshi; Oshima, Tadayuki; Miwa, Hiroto; Tashiro, Chikara; Nishizaki, Tomoyuki

    2008-03-01

    The present study investigated proliferation of MKN28 and MKN45 human gastric cancer cells regulated by the N-methyl-d-aspartate (NMDA) receptor subunit. The NMDA receptor antagonist dl-2-amino-5-phosphonovaleric acid (AP5) inhibited proliferation of MKN45 cells, but not MKN28 cells. Of the NMDA subunits such as NR1, NR2 (2A, 2B, 2C, and 2D), and NR3 (3A and 3B), all the NMDA subunit mRNAs except for the NR2B subunit mRNA were expressed in both MKN28 and MKN45 cells. MKN45 cells were characterized by higher expression of the NR2A subunit mRNA and lower expression of the NR1 subunit mRNA, but MKN28 otherwise by higher expression of the NR1 subunit mRNA and lower expression of the NR2A subunit mRNA. MKN45 cell proliferation was also inhibited by silencing the NR2A subunit-targeted gene. For MKN45 cells, AP5 or knocking-down the NR2A subunit increased the proportion of cells in the G(1) phase of cell cycling and decreased the proportion in the S/G(2) phase. The results of the present study, thus, suggest that blockage of NMDA receptors including the NR2A subunit suppresses MKN45 cell proliferation due to cell cycle arrest at the G(1) phase; in other words, the NR2A subunit promotes MKN45 cell proliferation by accelerating cell cycling. PMID:18178157

  10. The NMDA receptor NR2A subunit regulates proliferation of MKN45 human gastric cancer cells

    International Nuclear Information System (INIS)

    The present study investigated proliferation of MKN28 and MKN45 human gastric cancer cells regulated by the N-methyl-D-aspartate (NMDA) receptor subunit. The NMDA receptor antagonist DL-2-amino-5-phosphonovaleric acid (AP5) inhibited proliferation of MKN45 cells, but not MKN28 cells. Of the NMDA subunits such as NR1, NR2 (2A, 2B, 2C, and 2D), and NR3 (3A and 3B), all the NMDA subunit mRNAs except for the NR2B subunit mRNA were expressed in both MKN28 and MKN45 cells. MKN45 cells were characterized by higher expression of the NR2A subunit mRNA and lower expression of the NR1 subunit mRNA, but MKN28 otherwise by higher expression of the NR1 subunit mRNA and lower expression of the NR2A subunit mRNA. MKN45 cell proliferation was also inhibited by silencing the NR2A subunit-targeted gene. For MKN45 cells, AP5 or knocking-down the NR2A subunit increased the proportion of cells in the G1 phase of cell cycling and decreased the proportion in the S/G2 phase. The results of the present study, thus, suggest that blockage of NMDA receptors including the NR2A subunit suppresses MKN45 cell proliferation due to cell cycle arrest at the G1 phase; in other words, the NR2A subunit promotes MKN45 cell proliferation by accelerating cell cycling

  11. Electronic Structures and Spectroscopic Properties of a Novel Iridium (III) Complex with an Ancillary Ligand 2-(4-Trifluoromethyl -2-Hydroxylphenyl) Benzothiazole

    International Nuclear Information System (INIS)

    Iridium (III) complexes with 2-phenylpyridine (ppy) have been demonstrated as a type of promising phosphorescence dopant in emitting layers of organic light emitting diodes (OLEDs). In most iridium (III) complexes, there exist the strong spin-orbit coupling between π-orbitals of cyclometalated ligands and 5d orbitals of the centric iridium. We study a novel iridium (III) complex (ppy)2Ir(4-TfmBTZ) with ppy as cyclometalated ligands and 2-(4-trifluoromethyl-2-hydroxylphenyl)benzothiazole (4-TfmBTZ) as an ancillary ligand using the Gaussian 03 program. The geometries, electronic structures and spectroscopic properties of this iridium (III) complex are investigated by density functional theory (DFT) and time-dependent density functional theory (TD-DFT). The results show that the spin-orbit coupling occurs not only between ppy and iridium atom but also between 4-TfmBTZ and iridium atom in this complex. The highest occupied molecular orbital is dominantly localized on the Ir atom and 4-TfmBTZ ligand, while the lowest unoccupied molecular orbital on 4-TfmBTZ ligand. The triplet lowest-lying transition is attributed to the Ir-to-4-TfmBTZ charge-transfer (3MLCT) transition while the sub-low-lying transitions are assigned to the 3MLCT transitions of Ir(ppy)2. The nature of the lowest unoccupied orbital changes from ppy-localized to 4-TfmBTZ-localized and reveals that phosphorescent color of Ir(III) complex can be controlled by the ancillary ligand and substituent. (atomic and molecular physics)

  12. Fluorescence In Situ Hybridization for MDM2 Amplification as a Routine Ancillary Diagnostic Tool for Suspected Well-Differentiated and Dedifferentiated Liposarcomas: Experience at a Tertiary Center

    Directory of Open Access Journals (Sweden)

    Khin Thway

    2015-01-01

    Full Text Available Background. The assessment of MDM2 gene amplification by fluorescence in situ hybridization (FISH has become a routine ancillary tool for diagnosing atypical lipomatous tumor (ALT/well-differentiated liposarcoma and dedifferentiated liposarcoma (WDL/DDL in specialist sarcoma units. We describe our experience of its utility at our tertiary institute. Methods. All routine histology samples in which MDM2 amplification was assessed with FISH over a 2-year period were included, and FISH results were correlated with clinical and histologic findings. Results. 365 samples from 347 patients had FISH for MDM2 gene amplification. 170 were positive (i.e., showed MDM2 gene amplification, 192 were negative, and 3 were technically unsatisfactory. There were 122 histologically benign cases showing a histology:FISH concordance rate of 92.6%, 142 WDL/DDL (concordance 96.5%, and 34 cases histologically equivocal for WDL (concordance 50%. Of 64 spindle cell/pleomorphic neoplasms (in which DDL was a differential diagnosis, 21.9% showed MDM2 amplification. Of the cases with discrepant histology and FISH, all but 3 had diagnoses amended following FISH results. For discrepancies of benign histology but positive FISH, lesions were on average larger, more frequently in “classical” (intra-abdominal or inguinal sites for WDL/DDL and more frequently core biopsies. Discrepancies of malignant histology but negative FISH were smaller, less frequently in “classical” sites but again more frequently core biopsies. Conclusions. FISH has a high correlation rate with histology for cases with firm histologic diagnoses of lipoma or WDL/DDL. It is a useful ancillary diagnostic tool in histologically equivocal cases, particularly in WDL lacking significant histologic atypia or DDL without corresponding WDL component, especially in larger tumors, those from intra-abdominal or inguinal sites or core biopsies. There is a significant group of well-differentiated adipocytic neoplasms

  13. Sortase A substrate specificity in GBS pilus 2a cell wall anchoring.

    Directory of Open Access Journals (Sweden)

    Francesca Necchi

    Full Text Available Streptococcus agalactiae, also referred to as Group B Streptococcus (GBS, is one of the most common causes of life-threatening bacterial infections in infants. In recent years cell surface pili have been identified in several Gram-positive bacteria, including GBS, as important virulence factors and promising vaccine candidates. In GBS, three structurally distinct types of pili have been discovered (pilus 1, 2a and 2b, whose structural subunits are assembled in high-molecular weight polymers by specific class C sortases. In addition, the highly conserved housekeeping sortase A (SrtA, whose main role is to link surface proteins to bacterial cell wall peptidoglycan by a transpeptidation reaction, is also involved in pili cell wall anchoring in many bacteria. Through in vivo mutagenesis, we demonstrate that the LPXTG sorting signal of the minor ancillary protein (AP2 is essential for pilus 2a anchoring. We successfully produced a highly purified recombinant SrtA (SrtA(ΔN40 able to specifically hydrolyze the sorting signal of pilus 2a minor ancillary protein (AP2-2a and catalyze in vitro the transpeptidation reaction between peptidoglycan analogues and the LPXTG motif, using both synthetic fluorescent peptides and recombinant proteins. By contrast, SrtA(ΔN40 does not catalyze the transpeptidation reaction with substrate-peptides mimicking sorting signals of the other pilus 2a subunits (the backbone protein and the major ancillary protein. Thus, our results add further insight into the proposed model of GBS pilus 2a assembly, in which SrtA is required for pili cell wall covalent attachment, acting exclusively on the minor accessory pilin, representing the terminal subunit located at the base of the pilus.

  14. Structure of Csm2 elucidates the relationship between small subunits of CRISPR-Cas effector complexes.

    Science.gov (United States)

    Venclovas, Česlovas

    2016-05-01

    Type I and type III CRISPR-Cas effector complexes share similar architecture and have homologous key subunits. However, the relationship between the so-called small subunits of these complexes remains a contentious issue. Here, it is shown that the recently solved structure of Thermotoga maritima Csm2 represents a dimer with the extensive structure swapping between monomers. Unswapping the structure generates a compact globular monomer which shares similar structure and surface properties with Cmr5, the small subunit of a related Cmr complex. Detailed analysis of available structures of small subunits reveals that they all have a common fold suggesting their common origin. PMID:27091242

  15. Genetic Diversity of High and Low Molecular Weight Glutenin Subunits in Algerian Aegilops geniculata

    Directory of Open Access Journals (Sweden)

    Asma MEDOURI

    2014-12-01

    Full Text Available Aegilops geniculata Roth is an annual grass relative to cultivated wheat and is widely distributed in North Algeria. Endosperm storage proteins of wheat and its relatives, namely glutenins and gliadins, play an important role in dough properties and bread making quality. In the present study, the different alleles encoded at the four glutenin loci (Glu-M1, Glu-U1, Glu-M3 and Glu-U3 were identified from thirty five accessions of the tetraploid wild wheat A. geniculata collected in Algeria using Sodium dodecyl Sulfate - Polyacrylamide Gel Electrophoresis (SDS-PAGE. At Glu-M1 and Glu-U1 loci, encoding high molecular weight glutenin subunits (HMW-GS or A-subunits, 15 and 12 alleles were observed respectively, including one new subunit. B-Low molecular weight glutenin subunits zone (B-LMW-GS displayed a far greater variation, as 28 and 25 alleles were identified at loci Glu-M3 and Glu-U3 respectively. Thirty two subunits patterns were revealed at the C subunits- zone and a total of thirty four patterns resulted from the genetic combination of the two zones (B- and C-zone. The wide range of glutenin subunits variation (high molecular weight glutenin subunits and low molecular weight glutenin subunits in this species has the potential to enhance the genetic variability for improving the quality of wheat./span>

  16. Structure–Function Relationships in Fungal Large-Subunit Catalases

    Energy Technology Data Exchange (ETDEWEB)

    Diaz, A.; Valdez, V; Rudino-Pinera, E; Horjales, E; Hansberg, W

    2009-01-01

    Neurospora crassa has two large-subunit catalases, CAT-1 and CAT-3. CAT-1 is associated with non-growing cells and accumulates particularly in asexual spores; CAT-3 is associated with growing cells and is induced under different stress conditions. It is our interest to elucidate the structure-function relationships in large-subunit catalases. Here we have determined the CAT-3 crystal structure and compared it with the previously determined CAT-1 structure. Similar to CAT-1, CAT-3 hydrogen peroxide (H{sub 2}O{sub 2}) saturation kinetics exhibited two components, consistent with the existence of two active sites: one saturated in the millimolar range and the other in the molar range. In the CAT-1 structure, we found three interesting features related to its unusual kinetics: (a) a constriction in the channel that conveys H{sub 2}O{sub 2} to the active site; (b) a covalent bond between the tyrosine, which forms the fifth coordination bound to the iron of the heme, and a vicinal cysteine; (c) oxidation of the pyrrole ring III to form a cis-hydroxyl group in C5 and a cis-{gamma}-spirolactone in C6. The site of heme oxidation marks the starts of the central channel that communicates to the central cavity and the shortest way products can exit the active site. CAT-3 has a similar constriction in its major channel, which could function as a gating system regulated by the H{sub 2}O{sub 2} concentration before the gate. CAT-3 functional tyrosine is not covalently bonded, but has instead the electron relay mechanism described for the human catalase to divert electrons from it. Pyrrole ring III in CAT-3 is not oxidized as it is in other large-subunit catalases whose structure has been determined. Different in CAT-3 from these enzymes is an occupied central cavity. Results presented here indicate that CAT-3 and CAT-1 enzymes represent a functional group of catalases with distinctive structural characteristics that determine similar kinetics.

  17. Structure-function relationships in fungal large-subunit catalases.

    Science.gov (United States)

    Díaz, Adelaida; Valdés, Víctor-Julián; Rudiño-Piñera, Enrique; Horjales, Eduardo; Hansberg, Wilhelm

    2009-02-13

    Neurospora crassa has two large-subunit catalases, CAT-1 and CAT-3. CAT-1 is associated with non-growing cells and accumulates particularly in asexual spores; CAT-3 is associated with growing cells and is induced under different stress conditions. It is our interest to elucidate the structure-function relationships in large-subunit catalases. Here we have determined the CAT-3 crystal structure and compared it with the previously determined CAT-1 structure. Similar to CAT-1, CAT-3 hydrogen peroxide (H(2)O(2)) saturation kinetics exhibited two components, consistent with the existence of two active sites: one saturated in the millimolar range and the other in the molar range. In the CAT-1 structure, we found three interesting features related to its unusual kinetics: (a) a constriction in the channel that conveys H(2)O(2) to the active site; (b) a covalent bond between the tyrosine, which forms the fifth coordination bound to the iron of the heme, and a vicinal cysteine; (c) oxidation of the pyrrole ring III to form a cis-hydroxyl group in C5 and a cis-gamma-spirolactone in C6. The site of heme oxidation marks the starts of the central channel that communicates to the central cavity and the shortest way products can exit the active site. CAT-3 has a similar constriction in its major channel, which could function as a gating system regulated by the H(2)O(2) concentration before the gate. CAT-3 functional tyrosine is not covalently bonded, but has instead the electron relay mechanism described for the human catalase to divert electrons from it. Pyrrole ring III in CAT-3 is not oxidized as it is in other large-subunit catalases whose structure has been determined. Different in CAT-3 from these enzymes is an occupied central cavity. Results presented here indicate that CAT-3 and CAT-1 enzymes represent a functional group of catalases with distinctive structural characteristics that determine similar kinetics. PMID:19109972

  18. The phosphorylation pattern of bovine heart complex I subunits

    DEFF Research Database (Denmark)

    Palmisano, Giuseppe; Sardanelli, Anna Maria; Signorile, Anna;

    2007-01-01

    The phosphoproteome of bovine heart complex I of the respiratory chain has been analysed with a procedure based on nondenaturing gel electrophoretic separation of complex I from small quantities of mitochondria samples, in-gel digestion, in combination with phosphopeptide enrichment by titanium...... dioxide and MS. The results, complemented by analyses of purified samples of complex I, showed phosphorylation of five subunits of the complex, 42 kDa (human gene NDUFA10), ESSS, B14.5a (human gene NDUFA7), B14.5b (human gene NDUFC2) and B16.6 (GRIM-19). MS also revealed the presence of phosphorylated...... programmed cell death protein 8(AIF) in native and purified samples of complex I analysed. The possible physiological relevance of these findings is discussed....

  19. Manipulation of Subunit Stoichiometry in Heteromeric Membrane Proteins.

    Science.gov (United States)

    Morales-Perez, Claudio L; Noviello, Colleen M; Hibbs, Ryan E

    2016-05-01

    The ability of oligomeric membrane proteins to assemble in different functional ratios of subunits is a common feature across many systems. Recombinant expression of hetero-oligomeric proteins with defined stoichiometries facilitates detailed structural and functional analyses, but remains a major challenge. Here we present two methods for overcoming this challenge: one for rapid virus titration and another for stoichiometry determination. When these methods are coupled, they allow for efficient dissection of the heteromer stoichiometry problem and optimization of homogeneous protein expression. We demonstrate the utility of the methods in a system that to date has proved resistant to atomic-scale structural study, the nicotinic acetylcholine receptor. Leveraging these two methods, we have successfully expressed, purified, and grown diffraction-quality crystals of this challenging target. PMID:27041595

  20. Glycine Receptor α2 Subunit Activation Promotes Cortical Interneuron Migration

    Directory of Open Access Journals (Sweden)

    Ariel Avila

    2013-08-01

    Full Text Available Glycine receptors (GlyRs are detected in the developing CNS before synaptogenesis, but their function remains elusive. This study demonstrates that functional GlyRs are expressed by embryonic cortical interneurons in vivo. Furthermore, genetic disruption of these receptors leads to interneuron migration defects. We discovered that extrasynaptic activation of GlyRs containing the α2 subunit in cortical interneurons by endogenous glycine activates voltage-gated calcium channels and promotes calcium influx, which further modulates actomyosin contractility to fine-tune nuclear translocation during migration. Taken together, our data highlight the molecular events triggered by GlyR α2 activation that control cortical tangential migration during embryogenesis.

  1. Purification and subunit composition of atrial natriuretic peptide receptor

    International Nuclear Information System (INIS)

    A receptor for atrial natriuretic peptide (ANP) was purified 2700-fold, to apparent homogeneity, from cultured bovine aortic smooth muscle cells by affinity chromatography. The native ANP receptor has a molecular weight of 125,000 as determined by both metrizamide gradient centrifugation and nonreducing NaDodSO4/polyacrylamide gel electrophoresis. With 125I-labeled ANP as ligand, the purified receptor bound a maximum of 5.70 nmol of ligand per mg of protein and the dissociation constant was 4.0 X 10(-10)M. Upon treatment with 10 mM dithiothreitol, the purified receptor migrated as a single band at Mr 60,500 in NaDodSO4/polyacrylamide gel electrophoresis. These findings show that the holoreceptor for ANP in vascular tissue is composed of two subunits of identical apparent molecular weight, presumably linked by a disulfide bridge(s)

  2. Nasal reconstruction based on aesthetic subunits in Orientals.

    Science.gov (United States)

    Yotsuyanagi, T; Yamashita, K; Urushidate, S; Yokoi, K; Sawada, Y

    2000-07-01

    Reconstruction based on the aesthetic subunit principle has yielded good aesthetic outcomes in patients with moderate to severe nasal defects caused by trauma or tumor resection. However, the topographic subunits previously proposed are often unsuitable for Orientals. Compared with the nose in white patients, the nose in Orientals is low, lacks nasal muscle, and has a flat glabella; the structural features of the underlying cartilage and bone are not distinctly reflected in outward appearance. The authors devised aesthetic subunits suitable for Orientals, and they used these units to reconstruct various parts of the nose. The major difference between these units and those presented previously is the lack of soft triangles and the addition of the glabella as an independent unit. The authors divided the nose into the following five topographic units: the glabella, the nasal dorsum, the nasal tip, and the two alae. The border of the nasal dorsum unit was extended to above the maxillonasal suture. The basic reconstruction techniques use a V-Y advancement flap from the forehead to reconstruct the glabella, an island flap from the forehead to reconstruct the nasal dorsum and nasal tip, a nasolabial flap to reconstruct an ala, and a malar flap to reconstruct the cheek. A combination of flaps was used when the defect involved more than one unit. This concept was used for nasal reconstruction in 24 patients. In one patient undergoing reconstruction of the nasal dorsum and in one undergoing reconstruction of the nasal tip, the texture of the forearm flap did not match well, which resulted in a slightly unsatisfactory aesthetic outcome. In one patient in whom the glabella, nasal dorsum, and part of the cheek were reconstructed simultaneously, a web was formed at the medial ocular angle, and a secondary operation was subsequently performed using Z-plasty. In one patient undergoing reconstruction with a forehead flap, defatting was required to reduce the bulk of the

  3. Chaperonin Structure - The Large Multi-Subunit Protein Complex

    Directory of Open Access Journals (Sweden)

    Irena Roterman

    2009-03-01

    Full Text Available The multi sub-unit protein structure representing the chaperonins group is analyzed with respect to its hydrophobicity distribution. The proteins of this group assist protein folding supported by ATP. The specific axial symmetry GroEL structure (two rings of seven units stacked back to back - 524 aa each and the GroES (single ring of seven units - 97 aa each polypeptide chains are analyzed using the hydrophobicity distribution expressed as excess/deficiency all over the molecule to search for structure-to-function relationships. The empirically observed distribution of hydrophobic residues is confronted with the theoretical one representing the idealized hydrophobic core with hydrophilic residues exposure on the surface. The observed discrepancy between these two distributions seems to be aim-oriented, determining the structure-to-function relation. The hydrophobic force field structure generated by the chaperonin capsule is presented. Its possible influence on substrate folding is suggested.

  4. Effective polymer adjuvants for sustained delivery of protein subunit vaccines.

    Science.gov (United States)

    Adams, Justin R; Haughney, Shannon L; Mallapragada, Surya K

    2015-03-01

    We have synthesized thermogelling cationic amphiphilic pentablock copolymers that have the potential to act as injectable vaccine carriers and adjuvants that can simultaneously provide sustained delivery and enhance the immunogenicity of released antigen. While these pentablock copolymers have shown efficacy in DNA delivery in past studies, the ability to deliver both DNA and protein for subunit vaccines using the same polymeric carrier can provide greater flexibility and efficacy. We demonstrate the ability of these pentablock copolymers, and the parent triblock Pluronic copolymers to slowly release structurally intact and antigenically stable protein antigens in vitro, create an antigen depot through long-term injection-site persistence and enhance the in vivo immune response to these antigens. We show release of the model protein antigen ovalbumin in vitro from the thermogelling block copolymers with the primary, secondary and tertiary structures of the released protein unchanged compared to the native protein, and its antigenicity preserved upon release. The block copolymers form a gel at physiological temperatures that serves as an antigenic depot and persists in vivo at the site of injection for over 50days. The pentablock copolymers show a significant fivefold enhancement in the immune response compared to soluble protein alone, even 6weeks after the administration, based on measurement of antibody titers. These results demonstrate the potential of these block copolymers hydrogels to persist for several weeks and sustain the release of antigen with minimal effects on protein stability and antigenicity; and their ability to be used simultaneously as a sustained delivery device as well as a subunit vaccine adjuvant platform. PMID:25484331

  5. Prokaryotic expression of Chinese bovine enterokinase catalytic subunit

    Institute of Scientific and Technical Information of China (English)

    黄鹤; 赵阳; 甘一如

    2004-01-01

    Background To express in vitro the bovine enterokinase catalytic subunit (EKL ) protein, which could be used in the future for the cleavage and purification of fusion proteins. Methods Bovine enterokinase catalytic subunit cDNA was obtained by RT-PCR from the duodenal mucosa of a bovine obtained at a wholesale market, and then cloned into a pUCmT cloning vector and sequenced. The desired gene fragment was inserted into a pET39b expression plasmid and the recombinant vector pET39b-EKL was transformed into E. coli BL21 (DE3). Protein expression was induced using IPTG. The recombinant DsbA-EK, was purified with His · Tag affinity chromatography, and its bioactivity was analyzed. Results Compared with the sequence deposited in GenBank, the sequence of the EKL gene cloned in the present study is correct. It was also confirmed that the nucleotide sequence of expression plasmid pET39b-EKL was correct at the conjunction site between the recombinant DNA 5'terminal multi-cloning site and the recombinant fragment. SDS-PAGE analysis indicated that the target product was about 65 kDa and represented 28% of total cell protein. Purified recombinant protein was obtained by metal chelating chromatography using a NJ-IDA resin, After desalting and changing the buffer, the crude kinase was incubated at 21℃ overnight and shown to have a high autocatalytic cleavage activity. Conclusion The EKE gene from a Chinese bovine has been cloned successfully and expressed. This investigation has layed the foundation for future enterokinase activity research and for further large-scale application of expression products.

  6. The subunit structure of the extracellular hemoglobin of Biomphalaria glabrata

    International Nuclear Information System (INIS)

    Full text. The hemoglobin of Biomphalaria glabrata was purified to homogeneity by a two step purification protocol using a gel filtration column (Superose 6 HR/Pharmacia ) followed by an anion exchange chromatography (MONO-Q Sepharose/Pharmacia). The dissociation products were analysed by a 5 - 15 % Polyacrylamide gel electrophoresis containing Sodium Dodecyl Sulfate (SDS-PAGE) giving a band of 270 K Daltons and a band of 180 K Daltons after reduction with β-mercaptoethanol. The same profile was obtained in a 3.5 % Agarose gel electrophoresis containing SDS (SDS-AGE) showing additional bands of higher molecular weight. These bands were proposed to be monomers, dimers and trimers and, after reduction in a Bidimensional SDS-AGE, the proposed monomers and dimers were decomposed in two and four bands that were interpreted as 1 - 4 chains. The hemoglobin was digested by four different proteases ( Thrombin, Trypsin, Chymotrypsin and Subtilisin ) showing several equivalent fragments with molecular weights multiples of its minimum molecular weight ( 17.7 K Daltons). The circular dichroism spectrum of the protein showed a characteristic high α-helix content. We proposed that this hemoglobin is a pentamer of approx. 360 K Daltons subunits each formed by two 180 K Daltons chains linked in pairs by disulfide bridges and each of these chains comprises ten Heme binding domains. These data were compared to other Planorbidae extracellular hemoglobins. Up to now, the quaternary structure of this hemoglobin (shape and disposition of the subunits) is unknown. It is intended to elucidate its structure by Small Angle X-Ray Scattering in Brazilian National Laboratory of Synchrotron Light (LNLS). (author)

  7. Proteomic analysis of transducin beta-subunit structural heterogeneity.

    Science.gov (United States)

    Clack, James W; Juhl, Martha; Rice, Carol A; Li, Junyu; Witzmann, Frank A

    2003-10-01

    Partially purified transducin was resolved using two-dimensional gel electrophoresis (2-DE). Peptide mass fingerprinting of several different spots believed to correspond to the 37 kDa beta-subunit of transducin (T(beta)) was performed. Spots were excised and proteolyzed using modified trypsin. Matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS) was performed on the peptide mixture resulting from each spot. As many as six spots with different pI, ranging from 5.2 to 6.1, were observed when separated using 2-DE. MALDI peptide mass fingerprinting determined with high probability that all of the spots were the same gene product, guanine nucleotide-binding protein G(I)/G(S)/G(T) beta-subunit 1 (GNB1; T(beta1)). This suggested that post-translational modification was responsible for the differences in pI. Phosphorylation experiments showed that at least one T(beta1) spot was phosphorylated in vitro with [gamma-(32)P]ATP by an endogenous kinase. Treatment of T(beta) with alkaline phosphatase caused a large change in the spot pattern of T(beta), suggesting that phosphorylated T(beta) is a substrate for alkaline phosphatase. We conclude that T(beta1) constitutes over 99% of the T(beta) expressed in bovine rod outer segments and displays structural heterogeneity that is due to post-translational modification. We also conclude that some, but not all, of the heterogeneity observed is due to phosphorylation of Tb1. PMID:14595696

  8. Differential regulation of thyrotropin subunit apoprotein and carbohydrate biosynthesis by thyroid hormone

    International Nuclear Information System (INIS)

    The regulation of TSH apoprotein and carbohydrate biosynthesis by thyroid hormone was studied by incubating pituitaries from normal and hypothyroid (3 weeks post-thyroidectomy) rats in medium containing [14C]alanine and [3H] glucosamine. After 6 h, samples were sequentially treated with anti-TSH beta to precipitate TSH and free TSH beta, anti-LH beta to clear the sample of LH and free LH beta, then anti-LH alpha to precipitate free alpha-subunit. Total proteins were acid precipitated. All precipitates were subjected to electrophoresis on sodium dodecyl sulfate-polyacrylamide gels, which were then sliced and assayed by scintillation spectrometry. In hypothyroid pituitaries plus medium, [14C]alanine incorporation in combined and free beta-subunits was 26 times normal and considerably greater than the 3.4-fold increase seen in total protein; combined and free alpha-subunits showed no specific increase in apoprotein synthesis. [3H]Glucosamine incorporation in combined alpha- and beta-subunits in hypothyroid samples was 13 and 21 times normal, respectively, and was greater than the 1.9-fold increase in total protein; free alpha-subunit showed no specific increase in carbohydrate synthesis. The glucosamine to alanine ratio, reflecting relative glycosylation of newly synthesized molecules, was increased in hypothyroidism for combined alpha-subunits, but not for combined beta-subunits, free alpha-subunits, or total proteins. In summary, short term hypothyroidism selectively stimulated TSH beta apoprotein synthesis and carbohydrate synthesis of combined alpha- and beta-subunits. Hypothyroidism also increased the relative glycosylation of combined alpha-subunit. Thus, thyroid hormone deficiency appears to alter the rate-limiting step in TSH assembly (i.e. beta-subunit synthesis) as well as the carbohydrate structure of TSH, which may play important roles in its biological function

  9. Roles of the β subunit hinge domain in ATP synthase F1 sector: Hydrophobic network formed by introduced βPhe174 inhibits subunit rotation

    International Nuclear Information System (INIS)

    The ATP synthase β subunit hinge domain (βPhe148 ∼ βGly186, P-loop/α-helixB/loop/β-sheet4, Escherichia coli residue numbering) dramatically changes in conformation upon nucleotide binding. We previously reported that F1 with the βSer174 to Phe mutation in the domain lowered the γ subunit rotation speed, and thus decreased the ATPase activity [M. Nakanishi-Matsui, S. Kashiwagi, T. Ubukata, A. Iwamoto-Kihara, Y. Wada, M. Futai, Rotational catalysis of Escherichia coli ATP synthase F1 sector. Stochastic fluctuation and a key domain of the β subunit, J. Biol. Chem. 282 (2007) 20698-20704.]. Homology modeling indicates that the amino acid replacement induces a hydrophobic network, in which the βMet159, βIle163, and βAla167 residues of the β subunit are involved together with the mutant βPhe174. The network is expected to stabilize the conformation of βDP (nucleotide-bound form of the β subunit), resulting in increased activation energy for transition to βE (empty β subunit). The modeling further predicts that replacement of βMet159 with Ala or Ile weakens the hydrophobic network. As expected, these two mutations experimentally suppressed the ATPase activities as well as subunit rotation of βS174F. Furthermore, the rotation rate decreased with the increase of the strength in the hydrophobic network. These results indicate that the smooth conformational change of the β subunit hinge domain is pertinent for the rotational catalysis.

  10. Copolymer semiconductors comprising thiazolothiazole or benzobisthiazole, or benzobisoxazole electron acceptor subunits, and electron donor subunits, and their uses in transistors and solar cells

    Science.gov (United States)

    Jenekhe, Samson A; Subramaniyan, Selvam; Ahmed, Eilaf; Xin, Hao; Kim, Felix Sunjoo

    2014-10-28

    The inventions disclosed, described, and/or claimed herein relate to copolymers comprising copolymers comprising electron accepting A subunits that comprise thiazolothiazole, benzobisthiazole, or benzobisoxazoles rings, and electron donating subunits that comprise certain heterocyclic groups. The copolymers are useful for manufacturing organic electronic devices, including transistors and solar cells. The invention also relates to certain synthetic precursors of the copolymers. Methods for making the copolymers and the derivative electronic devices are also described.

  11. Amino acid sequence of the alpha subunit and computer modelling of the alpha and beta subunits of echicetin from the venom of Echis carinatus (saw-scaled viper).

    Science.gov (United States)

    Polgár, J; Magnenat, E M; Peitsch, M C; Wells, T N; Saqi, M S; Clemetson, K J

    1997-04-15

    Echicetin, a heterodimeric protein from the venom of Echis carinatus, binds to platelet glycoprotein Ib (GPIb) and so inhibits platelet aggregation or agglutination induced by various platelet agonists acting via GPIb. The amino acid sequence of the beta subunit of echicetin has been reported and found to belong to the recently identified snake venom subclass of the C-type lectin protein family. Echicetin alpha and beta subunits were purified. N-terminal sequence analysis provided direct evidence that the protein purified was echicetin. The paper presents the complete amino acid sequence of the alpha subunit and computer models of the alpha and beta subunits. The sequence of alpha echicetin is highly similar to the alpha and beta chains of various heterodimeric and homodimeric C-type lectins. Neither of the fully reduced and alkylated alpha or beta subunits of echicetin inhibited the platelet agglutination induced by von Willebrand factor-ristocetin or alpha-thrombin. Earlier reports about the inhibitory activity of reduced and alkylated echicetin beta subunit might have been due to partial reduction of the protein. PMID:9163349

  12. Loss of Complex I activity in the Escherichia coli enzyme results from truncating the C-terminus of subunit K, but not from cross-linking it to subunits N or L.

    Science.gov (United States)

    Zhu, Shaotong; Canales, Alejandra; Bedair, Mai; Vik, Steven B

    2016-06-01

    Complex I is a multi-subunit enzyme of the respiratory chain with seven core subunits in its membrane arm (A, H, J, K, L, M, and N). In the enzyme from Escherichia coli the C-terminal ten amino acids of subunit K lie along the lateral helix of subunit L, and contribute to a junction of subunits K, L and N on the cytoplasmic surface. Using double cysteine mutagenesis, the cross-linking of subunit K (R99C) to either subunit L (K581C) or subunit N (T292C) was attempted. A partial yield of cross-linked product had no effect on the activity of the enzyme, or on proton translocation, suggesting that the C-terminus of subunit K has no dynamic role in function. To further elucidate the role of subunit K genetic deletions were constructed at the C-terminus. Upon the serial deletion of the last 4 residues of the C-terminus of subunit K, various results were obtained. Deletion of one amino acid had little effect on the activity of Complex I, but deletions of 2 or more amino acids led to total loss of enzyme activity and diminished levels of subunits L, M, and N in preparations of membrane vesicles. Together these results suggest that while the C-terminus of subunit K has no dynamic role in energy transduction by Complex I, it is vital for the correct assembly of the enzyme. PMID:26931547

  13. The epithelial sodium channel γ-subunit is processed proteolytically in human kidney

    DEFF Research Database (Denmark)

    Langkilde, Rikke Zachar; Skjødt, Karsten; Marcussen, Niels;

    2015-01-01

    The epithelial sodium channel (ENaC) of the kidney is necessary for extracellular volume homeostasis and normal arterial BP. Activity of ENaC is enhanced by proteolytic cleavage of the gamma-subunit and putative release of a 43-amino acid inhibitory tract from the gamma-subunit ectodomain. We hyp...

  14. Regulation of KV channel voltage-dependent activation by transmembrane β subunits

    Directory of Open Access Journals (Sweden)

    Xiaohui eSun

    2012-04-01

    Full Text Available Voltage-activated K+ (KV channels are important for shaping action potentials and maintaining resting membrane potential in excitable cells. KV channels contain a central pore-gate domain (PGD surrounded by four voltage-sensing domains (VSD. The VSDs will change conformation in response to alterations of the membrane potential thereby inducing the opening of the PGD. Many KV channels are heteromeric protein complexes containing auxiliary β subunits. These β subunits modulate channel expression and activity to increase functional diversity and render tissue specific phenotypes. This review focuses on the KV β subunits that contain transmembrane (TM segments including the KCNE family and the β subunits of large conductance, Ca2+- and voltage-activated K+ (BK channels. These TM β subunits affect the voltage-dependent activation of KV α subunits. Experimental and computational studies have described the structural location of these β subunits in the channel complexes and the biophysical effects on VSD activation, PGD opening and VSD-PGD coupling. These results reveal some common characteristics and mechanistic insights into KV channel modulation by TM β subunits.

  15. Similar GABAA receptor subunit composition in somatic and axon initial segment synapses of hippocampal pyramidal cells.

    Science.gov (United States)

    Kerti-Szigeti, Katalin; Nusser, Zoltan

    2016-01-01

    Hippocampal pyramidal cells (PCs) express many GABAAR subunit types and receive GABAergic inputs from distinct interneurons. Previous experiments revealed input-specific differences in α1 and α2 subunit densities in perisomatic synapses, suggesting distinct IPSC decay kinetics. However, IPSC decays evoked by axo-axonic, parvalbumin- or cholecystokinin-expressing basket cells were found to be similar. Using replica immunogold labeling, here we show that all CA1 PC somatic and AIS synapses contain the α1, α2, β1, β2, β3 and γ2 subunits. In CA3 PCs, 90% of the perisomatic synapses are immunopositive for the α1 subunit and all synapses are positive for the remaining five subunits. Somatic synapses form unimodal distributions based on their immunoreactivity for these subunits. The α2 subunit densities in somatic synapses facing Cav2.1 (i.e. parvalbumin) or Cav2.2 (cholecystokinin) positive presynaptic active zones are comparable. We conclude that perisomatic synapses made by three distinct interneuron types have similar GABAA receptor subunit content. PMID:27537197

  16. Differential expression of BK channel isoforms and beta-subunits in rat neuro-vascular tissues

    DEFF Research Database (Denmark)

    Poulsen, Asser Nyander; Johansson, Helle Wulf; Hay-Schmidt, Anders;

    2009-01-01

    We investigated the expression of splice variants and beta-subunits of the BK channel (big conductance Ca(2+)-activated K(+) channel, Slo1, MaxiK, K(Ca)1.1) in rat cerebral blood vessels, meninges, trigeminal ganglion among other tissues. An alpha-subunit splice variant X1(+24) was found expressed...

  17. HMW glutenin subunits in multiploid Aegilops species: composition analysis and molecular cloning of coding sequences

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The Aegilops genus contains species closely related to wheat. Incommon with wheat, Aegilops species accumulate high molecular weight (HMW) glutenin subunits in their endospermic tissue. In this study, we investigated the composition of HMW glutenin subunits in four multiploid Aegilops species using SDS-PAGE analysis. Furthermore, by working with Ae. ventricosa, we established an efficient genomic PCR condition for simultaneous amplification of DNA sequences coding for either x-ory-type HMW glutenin subunits from polyploid Aegilops species. Using the genomic PCR condition, we amplified and subsequently cloned two DNA fragments that may code for HMW glutenin subunits in Ae. ventricosa. Based on an analysis of the deduced amino acid sequences, we concluded that the two cloned sequences encode one x- and one y-type of HMW glutenin subunit, respectively.

  18. Functional consequences of Kir2.1/Kir2.2 subunit heteromerization.

    Science.gov (United States)

    Panama, Brian K; McLerie, Meredith; Lopatin, Anatoli N

    2010-10-01

    Kir2 subunits form channels that underlie classical strongly inwardly rectifying potassium currents. While homomeric Kir2 channels display a number of distinct and physiologically important properties, the functional properties of heteromeric Kir2 assemblies, as well as the stoichiometries and the arrangements of Kir2 subunits in native channels, remain largely unknown. Therefore, we have implemented a concatemeric approach, whereby all four cloned Kir2 subunits were linked in tandem, in order to study the effects of Kir2.1 and Kir2.2 heteromerization on properties of the resulting channels. Kir2.2 subunits contributed stronger to single-channel conductance than Kir2.1 subunits, and channels containing two or more Kir2.2 subunits displayed conductances indistinguishable from that of a Kir2.2 homomeric channel. In contrast, single-channel kinetics was a more discriminating property. The open times were significantly shorter in Kir2.2 channels compared with Kir2.1 channels and decreased nearly proportionally to the number of Kir2.2 subunits in the heteromeric channel. Similarly, the sensitivity to block by barium also depended on the proportions of Kir2.1 to Kir2.2 subunits. Overall, the results showed that Kir2.1 and Kir2.2 subunits exert neither a dominant nor an anomalous effect on any of the properties of heteromeric channels. The data highlight opportunities and challenges of using differential properties of Kir2 channels in deciphering the subunit composition of native inwardly rectifying potassium currents. PMID:20676672

  19. Distinctive interactions of the Arabidopsis homolog of the 30 kD subunit of the cleavage and polyadenylation specificity factor (AtCPSF30) with other polyadenylation factor subunits

    Science.gov (United States)

    Background: The Arabidopsis ortholog of the 30 kD subunit of the mammalian Cleavage and Polyadenylation Specificity Factor (AtCPSF30) is an RNA-binding endonuclease that is associated with other Arabidopsis CPSF subunits (orthologs of the 160, 100, and 73 kD subunits of CPSF). In order to better u...

  20. trt-1 is the Caenorhabditis elegans catalytic subunit of telomerase.

    Directory of Open Access Journals (Sweden)

    2006-02-01

    Full Text Available Mutants of trt-1, the Caenorhabditis elegans telomerase reverse transcriptase, reproduce normally for several generations but eventually become sterile as a consequence of telomere erosion and end-to-end chromosome fusions. Telomere erosion and uncapping do not cause an increase in apoptosis in the germlines of trt-1 mutants. Instead, late-generation trt-1 mutants display chromosome segregation defects that are likely to be the direct cause of sterility. trt-1 functions in the same telomere replication pathway as mrt-2, a component of the Rad9/Rad1/Hus1 (9-1-1 proliferating cell nuclear antigen-like sliding clamp. Thus, the 9-1-1 complex may be required for telomerase to act at chromosome ends in C. elegans. Although telomere erosion limits replicative life span in human somatic cells, neither trt-1 nor telomere shortening affects postmitotic aging in C. elegans. These findings illustrate effects of telomere dysfunction in C. elegans mutants lacking the catalytic subunit of telomerase, trt-1.

  1. Immunoradiometric assay of subunit H of human acidic isoferritin

    International Nuclear Information System (INIS)

    Acidic isoferritin (AIF) was isolated and purified from human heart muscle. Antisera against AIF were generated by immunizing rabbits and purified in affinity chromatography column which was conjugated with AIF. The immunoglobulins against AIF were made in solid-phase. 125I-monoclonal antibodies against H subunit of AIF(AIF-H) was prepared by the chloramine-T method. The AIF-H solid-phase IRMA was established and the data were processed by the automatic Spline function. The intra- and interbatch coefficients of variation were 2.443% and 10.160% respectively. The sensitivity was 0.736 μg/L and the recovery was 92.293%. The measuring range was 1.472-320 μg/L and ED50 was 23.05 μg/L. No cross-reaction was observed with AFP, CEA and LF, but there was 3.125% with ferritin. A parallel experiment demonstrated that serum matrix had no interference with this method. The level of serum AIF-H in 40 healthy men and women was 3.75 +- 1.85 μg/L and 2.92 +- 0.96 μg/L respectively while it was 8.39 +-3.87 μg/L in 10 patients with hepatoma. This method may therefore provide a valuable tool for diagnosis of tumor, especially for basic and clinical study of hepatoma

  2. Structure of the Tribolium castaneum Telomerase Catalytic Subunit TERT

    Energy Technology Data Exchange (ETDEWEB)

    Gillis,A.; Schuller, A.; Skordalakes, E.

    2008-01-01

    A common hallmark of human cancers is the overexpression of telomerase, a ribonucleoprotein complex that is responsible for maintaining the length and integrity of chromosome ends. Telomere length deregulation and telomerase activation is an early, and perhaps necessary, step in cancer cell evolution. Here we present the high-resolution structure of the Tribolium castaneum catalytic subunit of telomerase, TERT. The protein consists of three highly conserved domains, organized into a ring-like structure that shares common features with retroviral reverse transcriptases, viral RNA polymerases and B-family DNA polymerases. Domain organization places motifs implicated in substrate binding and catalysis in the interior of the ring, which can accommodate seven to eight bases of double-stranded nucleic acid. Modelling of an RNA-DNA heteroduplex in the interior of this ring demonstrates a perfect fit between the protein and the nucleic acid substrate, and positions the 3'-end of the DNA primer at the active site of the enzyme, providing evidence for the formation of an active telomerase elongation complex.

  3. Design of a hyperstable 60-subunit protein icosahedron

    Science.gov (United States)

    Hsia, Yang; Bale, Jacob B.; Gonen, Shane; Shi, Dan; Sheffler, William; Fong, Kimberly K.; Nattermann, Una; Xu, Chunfu; Huang, Po-Ssu; Ravichandran, Rashmi; Yi, Sue; Davis, Trisha N.; Gonen, Tamir; King, Neil P.; Baker, David

    2016-07-01

    The icosahedron is the largest of the Platonic solids, and icosahedral protein structures are widely used in biological systems for packaging and transport. There has been considerable interest in repurposing such structures for applications ranging from targeted delivery to multivalent immunogen presentation. The ability to design proteins that self-assemble into precisely specified, highly ordered icosahedral structures would open the door to a new generation of protein containers with properties custom-tailored to specific applications. Here we describe the computational design of a 25-nanometre icosahedral nanocage that self-assembles from trimeric protein building blocks. The designed protein was produced in Escherichia coli, and found by electron microscopy to assemble into a homogenous population of icosahedral particles nearly identical to the design model. The particles are stable in 6.7 molar guanidine hydrochloride at up to 80 degrees Celsius, and undergo extremely abrupt, but reversible, disassembly between 2 molar and 2.25 molar guanidinium thiocyanate. The icosahedron is robust to genetic fusions: one or two copies of green fluorescent protein (GFP) can be fused to each of the 60 subunits to create highly fluorescent ‘standard candles’ for use in light microscopy, and a designed protein pentamer can be placed in the centre of each of the 20 pentameric faces to modulate the size of the entrance/exit channels of the cage. Such robust and customizable nanocages should have considerable utility in targeted drug delivery, vaccine design and synthetic biology.

  4. Fc receptor gamma subunit polymorphisms and systemic lupus erythematosus

    International Nuclear Information System (INIS)

    To investigate the possible association between Fc receptor gamma polymorphisms and systemic lupus erythematosus (SLE). We have investigated the full FcR gamma gene for polymorphisms using polymerase chain reaction (PCR)-single strand confirmational polymorphisms and DNA sequencing .The polymorphisms identified were genotype using PCR-restriction fragment length polymorphism. Systemic lupus erythematosus cases and controls were available from 3 ethnic groups: Turkish, Spanish and Caucasian. The study was conducted in the year 2001 at the Arthritis Research Campaign, Epidemiology Unit, Manchester University Medical School, Manchester, United Kingdom. Five single nucleotide polymorphisms were identified, 2 in the promoter, one in intron 4 and, 2 in the 3'UTR. Four of the 5 single nucleotide polymorphisms (SNPs) were relatively common and investigated in the 3 populations. Allele and genotype frequencies of all 4 investigated SNPs were not statistically different cases and controls. fc receptor gamma gene does not appear to contribute to SLE susceptibility. The identified polymorphisms may be useful in investigating other diseases where receptors containing the FcR gamma subunit contribute to the pathology. (author)

  5. DNA binding properties of the small cascade subunit Csa5.

    Directory of Open Access Journals (Sweden)

    Michael Daume

    Full Text Available CRISPR-Cas systems provide immunity against viral attacks in archaeal and bacterial cells. Type I systems employ a Cas protein complex termed Cascade, which utilizes small CRISPR RNAs to detect and degrade the exogenic DNA. A small sequence motif, the PAM, marks the foreign substrates. Previously, a recombinant type I-A Cascade complex from the archaeon Thermoproteus tenax was shown to target and degrade DNA in vitro, dependent on a native PAM sequence. Here, we present the biochemical analysis of the small subunit, Csa5, of this Cascade complex. T. tenax Csa5 preferentially bound ssDNA and mutants that showed decreased ssDNA-binding and reduced Cascade-mediated DNA cleavage were identified. Csa5 oligomerization prevented DNA binding. Specific recognition of the PAM sequence was not observed. Phylogenetic analyses identified Csa5 as a universal member of type I-A systems and revealed three distinct groups. A potential role of Csa5 in R-loop stabilization is discussed.

  6. Expansion of transducin subunit gene families in early vertebrate tetraploidizations.

    Science.gov (United States)

    Lagman, David; Sundström, Görel; Ocampo Daza, Daniel; Abalo, Xesús M; Larhammar, Dan

    2012-10-01

    Hundreds of gene families expanded in the early vertebrate tetraploidizations including many gene families in the phototransduction cascade. We have investigated the evolution of the heterotrimeric G-proteins of photoreceptors, the transducins, in relation to these events using both phylogenetic analyses and synteny comparisons. Three alpha subunit genes were identified in amniotes and the coelacanth, GNAT1-3; two of these were identified in amphibians and teleost fish, GNAT1 and GNAT2. Most tetrapods have four beta genes, GNB1-4, and teleosts have additional duplicates. Finally, three gamma genes were identified in mammals, GNGT1, GNG11 and GNGT2. Of these, GNGT1 and GNGT2 were found in the other vertebrates. In frog and zebrafish additional duplicates of GNGT2 were identified. Our analyses show all three transducin families expanded during the early vertebrate tetraploidizations and the beta and gamma families gained additional copies in the teleost-specific genome duplication. This suggests that the tetraploidizations contributed to visual specialisations. PMID:22814267

  7. Vaults and telomerase share a common subunit, TEP1.

    Science.gov (United States)

    Kickhoefer, V A; Stephen, A G; Harrington, L; Robinson, M O; Rome, L H

    1999-11-12

    Vaults are large cytoplasmic ribonucleoprotein complexes of undetermined function. Mammalian vaults have two high molecular mass proteins of 193 and 240 kDa. We have identified a partial cDNA encoding the 240-kDa vault protein and determined it is identical to the mammalian telomerase-associated component, TEP1. TEP1 is the mammalian homolog of the Tetrahymena p80 telomerase protein and has been shown to interact specifically with mammalian telomerase RNA and the catalytic protein subunit hTERT. We show that while TEP1 is a component of the vault particle, vaults have no detectable telomerase activity. Using a yeast three-hybrid assay we demonstrate that several of the human vRNAs interact in a sequence-specific manner with TEP1. The presence of 16 WD40 repeats in the carboxyl terminus of the TEP1 protein is a convenient number for this protein to serve a structural or organizing role in the vault, a particle with eight-fold symmetry. The sharing of the TEP1 protein between vaults and telomerase suggests that TEP1 may play a common role in some aspect of ribonucleoprotein structure, function, or assembly. PMID:10551828

  8. The stoichiometry of P2X2/6 receptor heteromers depends on relative subunit expression levels

    OpenAIRE

    Barrera, Nelson P.; Henderson, Robert M.; Murrell-Lagnado, Ruth D.; Edwardson, J Michael

    2007-01-01

    Fast synaptic transmission involves the operation of ionotropic receptors, which are often composed of at least two types of subunit. We have developed a method, based on atomic force microscopy imaging to determine the stoichiometry and subunit arrangement within ionotropic receptors. We showed recently that the P2X(2) receptor for ATP is expressed as a trimer but that the P2X(6) subunit is unable to oligomerize. In this study we addressed the subunit stoichiometry of heteromers containing b...

  9. An extended nomenclature for mammalian V-ATPase subunit genes and splice variants.

    Directory of Open Access Journals (Sweden)

    Kevin C Miranda

    Full Text Available The vacuolar-type H(+-ATPase (V-ATPase is a multisubunit proton pump that is involved in both intra- and extracellular acidification processes throughout the body. Multiple homologs and splice variants of V-ATPase subunits are thought to explain its varied spatial and temporal expression pattern in different cell types. Recently subunit nomenclature was standardized with a total of 22 subunit variants identified. However this standardization did not accommodate the existence of splice variants and is therefore incomplete. Thus, we propose here an extension of subunit nomenclature along with a literature and sequence database scan for additional V-ATPase subunits. An additional 17 variants were pulled from a literature search while 4 uncharacterized potential subunit variants were found in sequence databases. These findings have been integrated with the current V-ATPase knowledge base to create a new V-ATPase subunit catalogue. It is envisioned this catalogue will form a new platform on which future studies into tissue- and organelle-specific V-ATPase expression, localization and function can be based.

  10. Insights into the subunit in-teractions of the chloroplast ATP synthase

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Subunit interactions of the chloroplast F0F1- ATP synthase were studied using the yeast two-hybrid system. The coding sequences of all the nine subunits of spinach chloroplast ATP synthase were cloned in two-hybrid vectors. The vectors were transformed into the yeast strains HF7c and SFY526 by various pairwise combinations, and the protein interactions were analyzed by measuring the yeast growth on minimal SD medium without serine, lucine and histidine. Interactions of γ Subunit with wild type or two truncated mutants of γ sununit, △εN21 and △εC45, which lose their abilities to inhibit the ATP hydrolysis, were also detected by in vitro and in vivo binding assay. The present results are largely accordant to the common structure model of F0F1-ATP synthase. Different from that in the E. Coli F0F1-ATP synthase, the δ subunit of chloroplast ATP syn- thase could interact with β,γ,ε and all the CF0 subunits in the two-hybrid system. These results suggested that though the chloroplast ATP synthase shares the similar structure and composition of subunits with the enzyme from E. Coli, it may be different in the subunit interactions and con- formational change during catalysis between these two sources of ATP synthase. Based on the present results and our knowledge of structure model of E. Coli ATP synthase, a deduced structure model of chloroplast ATP synthase was proposed.

  11. The cyclope gene of Drosophila encodes a cytochrome c oxidase subunit VIc homolog.

    Science.gov (United States)

    Szuplewski, S; Terracol, R

    2001-08-01

    Cytochrome c oxidase is the terminal enzyme of the mitochondrial electron transfer chain. In eukaryotes, the enzyme is composed of 3 mitochondrial DNA-encoded subunits and 7-10 (in mammals) nuclear DNA-encoded subunits. This enzyme has been extensively studied in mammals and yeast but, in Drosophila, very little is known and no mutant has been described so far. Here we report the genetic and molecular characterization of mutations in cyclope (cype) and the cloning of the gene encoding a cytochrome c oxidase subunit VIc homolog. cype is an essential gene whose mutations are lethal and show pleiotropic phenotypes. The 77-amino acid peptide encoded by cype is 46% identical and 59% similar to the human subunit (75 amino acids). The transcripts are expressed maternally and throughout development in localized regions. They are found predominantly in the central nervous system of the embryo; in the central region of imaginal discs; in the germarium, follicular, and nurse cells of the ovary; and in testis. A search in the Genome Annotation Database of Drosophila revealed the absence of subunit VIIb and the presence of 9 putative nuclear cytochrome c oxidase subunits with high identity scores when compared to the 10 human subunits. PMID:11514451

  12. Radioimmunodetection of choriocarcinoma in nude mouse by radiolabeled antibody to human chorionic gonadotropin. beta. -subunit

    Energy Technology Data Exchange (ETDEWEB)

    Yamanaka, Nozomu (Kobe Univ. (Japan). School of Medicine)

    1983-06-01

    Photoscans and organ radioactivity were assessed with radiolabeled antibodies to hCG or hCG-..beta.. subunit in nude mice bearing hCG-producing tumors. /sup 125/I-anti hCG or /sup 125/I-anti-hCG-..beta.. subunit was administered to nude mice bearing an hCG-producing tumor, GCH-lnu. Measurement of radioactivity revealed specific accumulation of both antibodies into the tumor. Especially the accumulation of /sup 125/I-anti hCG-..beta.. subunit on the 3rd day of administration was high, being about 4 times higher than the nonspecific accumulation in the liver. The localization of hCG in the tumor was examined by the indirect peroxidase-antiperoxidase method using anti-hCG. and anti hCG-..cap alpha.. subunit, and hCG-..beta.. subunit. The immunoperoxidase reaction was positive, and the accumulation of these radiolabeled antibodies in the tumor is suggested to be an immunologically specific phenomenon. The tumor in the tumor-bearing nude mouse injected with /sup 131/I-anti hCG or /sup 131/I-anti hCG-..beta.., subunit could be visualized as a hot area by external scintigraphy. Especially, the tumor image produced by the accumulation of anti hCG-..beta.. subunit was very clear against the background radiation.

  13. Different patterns of nicotinic acetylcholine receptor subunit transcription in human thymus.

    Science.gov (United States)

    Bruno, Roxana; Sabater, Lidia; Tolosa, Eva; Sospedra, Mireia; Ferrer-Francesch, Xavier; Coll, Jaume; Foz, Marius; Melms, Arthur; Pujol-Borrell, Ricardo

    2004-04-01

    Clinical observations suggest that the thymus is strongly implicated in the pathogenesis of myasthenia gravis (MG), but questions such as the level and location of nicotinic acetylcholine receptor (AChR) subunit expression that are fundamental to postulate any pathogenic mechanism, remain controversial. We have re-examined this question by combining calibrated RT-PCR and real-time PCR to study nicotinic AChR subunit mRNA expression in a panel of normal and myasthenic thymi. The results suggest that the expression of the different AChR subunits follows three distinct patterns: constitutive for, neonatal for gamma and individually variable for alpha1, beta1 and delta. Experiments using confocal laser microdissection suggest that AChR is mainly expressed in the medullary compartment of the thymus but there is not a clear compartmentalization of subunit expression. The different patterns of subunit expression may influence decisively the level of central tolerance to the subunits and explain the focusing of the T cell response to the alpha and gamma subunits. PMID:15020075

  14. Functional Diversification of Maize RNA Polymerase IV and V Subtypes via Alternative Catalytic Subunits

    Directory of Open Access Journals (Sweden)

    Jeremy R. Haag

    2014-10-01

    Full Text Available Unlike nuclear multisubunit RNA polymerases I, II, and III, whose subunit compositions are conserved throughout eukaryotes, plant RNA polymerases IV and V are nonessential, Pol II-related enzymes whose subunit compositions are still evolving. Whereas Arabidopsis Pols IV and V differ from Pol II in four or five of their 12 subunits, respectively, and differ from one another in three subunits, proteomic analyses show that maize Pols IV and V differ from Pol II in six subunits but differ from each other only in their largest subunits. Use of alternative catalytic second subunits, which are nonredundant for development and paramutation, yields at least two subtypes of Pol IV and three subtypes of Pol V in maize. Pol IV/Pol V associations with MOP1, RMR1, AGO121, Zm_DRD1/CHR127, SHH2a, and SHH2b extend parallels between paramutation in maize and the RNA-directed DNA methylation pathway in Arabidopsis.

  15. Structural characterization of recombinant crustacyanin subunits from the lobster Homarus americanus

    International Nuclear Information System (INIS)

    The two recombinant apo subunits H1 and H2 from H. americanus have been structurally characterized. Reconstitution studies with astaxanthin reproduced the bathochromic shift of 85–95 nm typical of the natural crustacyanin subunits. Crustacean crustacyanin proteins are linked to the production and modification of carapace colour, with direct implications for fitness and survival. Here, the structural and functional properties of the two recombinant crustacyanin subunits H1 and H2 from the American lobster Homarus americanus are reported. The two subunits are structurally highly similar to the corresponding natural apo crustacyanin CRTC and CRTA subunits from the European lobster H. gammarus. Reconstitution studies of the recombinant crustacyanin proteins H1 and H2 with astaxanthin reproduced the bathochromic shift of 85–95 nm typical of the natural crustacyanin subunits from H. gammarus in complex with astaxanthin. Moreover, correlations between the presence of crustacyanin genes in crustacean species and the resulting carapace colours with the spectral properties of the subunits in complex with astaxanthin confirmed this genotype–phenotype linkage

  16. Model-Based Estimation of Forest Canopy Height in Red and Austrian Pine Stands Using Shuttle Radar Topography Mission and Ancillary Data: a Proof-of-Concept Study

    Energy Technology Data Exchange (ETDEWEB)

    Brown Jr., C G; Sarabandi, K; Pierce, L E

    2007-04-06

    In this paper, accurate tree stand height retrieval is demonstrated using C-band Shuttle Radar Topography Mission (SRTM) height and ancillary data. The tree height retrieval algorithm is based on modeling uniform tree stands with a single layer of randomly oriented vegetation particles. For such scattering media, the scattering phase center height, as measured by SRTM, is a function of tree height, incidence angle, and the extinction coefficient of the medium. The extinction coefficient for uniform tree stands is calculated as a function of tree height and density using allometric equations and a fractal tree model. The accuracy of the proposed algorithm is demonstrated using SRTM and TOPSAR data for 15 red pine and Austrian pine stands (TOPSAR is an airborne interferometric synthetic aperture radar). The algorithm yields root-mean-square (rms) errors of 2.5-3.6 m, which is a substantial improvement over the 6.8-8.3-m rms errors from the raw SRTM minus National Elevation Dataset Heights.

  17. Evaluation of multiple ancillary therapies used in combination with an antimicrobial in newly received high-risk calves treated for bovine respiratory disease.

    Science.gov (United States)

    Wilson, B K; Step, D L; Maxwell, C L; Wagner, J J; Richards, C J; Krehbiel, C R

    2015-07-01

    Ancillary therapy (ANC) is commonly provided in conjunction with an antimicrobial when treating calves for suspected bovine respiratory disease (BRD) in an attempt to improve the response to a suspected BRD challenge. The first experiment evaluated the effects of 3 ANC in combination with an antimicrobial in high-risk calves treated for BRD during a 56-d receiving period. Newly received crossbred steers (n = 516; initial BW = 217 ± 20 kg) were monitored by trained personnel for clinical signs of BRD. Calves that met antimicrobial treatment criteria (n = 320) were then randomly assigned to experimental ANC treatment (80 steers/experimental ANC treatment): intravenous flunixin meglumine injection (NSAID), intranasal viral vaccination (VACC), intramuscular vitamin C injection (VITC), or no ANC (NOAC). Animal served as the experimental unit for all variables except DMI and G:F (pen served as the experimental unit for DMI and G:F). Within calves treated 3 times for BRD, those receiving NOAC had lower (P risk calves receiving antimicrobial treatment for suspected BRD. PMID:26440032

  18. A novel form of 6-phosphofructokinase. Identification and functional relevance of a third type of subunit in Pichia pastoris.

    Science.gov (United States)

    Tanneberger, Katrin; Kirchberger, Jürgen; Bär, Jörg; Schellenberger, Wolfgang; Rothemund, Sven; Kamprad, Manja; Otto, Henning; Schöneberg, Torsten; Edelmann, Anke

    2007-08-10

    Classically, 6-phosphofructokinases are homo- and hetero-oligomeric enzymes consisting of alpha subunits and alpha/beta subunits, respectively. Herein, we describe a new form of 6-phosphofructokinase (Pfk) present in several Pichia species, which is composed of three different types of subunit, alpha, beta, and gamma. The sequence of the gamma subunit shows no similarity to classic Pfk subunits or to other known protein sequences. In-depth structural and functional studies revealed that the gamma subunit is a constitutive component of Pfk from Pichia pastoris (PpPfk). Analyses of the purified PpPfk suggest a heterododecameric assembly from the three different subunits. Accordingly, it is the largest and most complex Pfk identified yet. Although, the gamma subunit is not required for enzymatic activity, the gamma subunit-deficient mutant displays a decreased growth on nutrient limitation and reduced cell flocculation when compared with the P. pastoris wild-type strain. Subsequent characterization of purified Pfks from wild-type and gamma subunit-deficient strains revealed that the allosteric regulation of the PpPfk by ATP, fructose 2,6-bisphosphate, and AMP is fine-tuned by the gamma subunit. Therefore, we suggest that the gamma subunit contributes to adaptation of P. pastoris to energy resources. PMID:17522059

  19. Molecular basis for differential modulation of BK channel voltage-dependent gating by auxiliary γ subunits.

    Science.gov (United States)

    Li, Qin; Fan, Fei; Kwak, Ha Rim; Yan, Jiusheng

    2015-06-01

    Large conductance Ca(2+)- and voltage-activated potassium (BK) channels are comprised of pore-forming α subunits and various regulatory auxiliary subunits. The BK channel auxiliary γ (BKγ) subunits are a newly identified class of proteins containing an extracellular leucine-rich repeat domain (LRRD), a single transmembrane (TM) segment, and a short cytoplasmic C-terminal tail (C-tail). Although each of the four BKγ proteins shifts the voltage dependence of BK channel activation in a hyperpolarizing direction, they show markedly different efficacies, mediating shifts over a range of 15-145 mV. Analyses of chimeric BKγ subunits created by swapping individual structural elements, and of BKγ deletion and substitution mutants, revealed that differential modulation of BK gating by the four BKγ subunits depends on a small region consisting of the TM segment and the adjacent intracellular cluster of positively charged amino acids. The γ1 and γ2 TM segments contributed approximately -100 mV, and the γ1 and γ3 C-tails contributed approximately -40 mV, to shifting the voltage dependence of BK channel activation, whereas the γ3 and γ4 TM segments and the γ2 and γ4 C-tails contributed much less. The large extracellular LRRDs were mainly functionally interchangeable, although the γ1 LRRD was slightly less effective at enhancing (or slightly more effective at attenuating) the shift in BK channel voltage-dependent gating toward hyperpolarizing potentials than those of the other BKγ subunits. Analysis of mutated BKγ subunits revealed that juxta-membrane clusters of positively charged amino acids determine the functions of the γ1 and γ3 C-tails. Therefore, the modulatory functions of BKγ subunits are coarse- and fine-tuned, respectively, through variations in their TM segments and in the adjacent intracellular positively charged regions. Our results suggest that BK channel modulation by auxiliary γ subunits depends on intra- and/or juxta-membrane mechanisms

  20. Further characterization of the subunits of the receptor with high affinity for immunoglobulin E

    International Nuclear Information System (INIS)

    The α, β, γ subunits of the receptor with high affinity for immunoglobulin E were isolated and their compositions assessed by direct amino acid analysis and by incorporation of radioactive precursors. The compositions show no unusual features other than a rather high content of tryptophan in the α chain as assessed from the incorporation studies. The results combined with future sequence data will permit unambiguous determination of the multiplicity of the chains in the receptor. Chymotryptic peptide maps of the extrinsically iodinated subunits show several similar peptides, particularly for α and β. However, these putative homologies were not apparent when tryptic maps of the biosynthetically ([3H]leucine) labeled subunits were analyzed

  1. Transcriptional organization of the phycocyanin subunit gene clusters of the cyanobacterium Anacystis nidulans UTEX 625.

    OpenAIRE

    Kalla, S R; Lind, L K; Lidholm, J; Gustafsson, P

    1988-01-01

    The phycocyanin subunit gene cluster is duplicated on the chromosome of the cyanobacterium Anacystis nidulans UTEX 625. The two gene clusters cpcB1A1 (left) and cpcB2A2 (right) are separated by about 2,500 base pairs, and in each cluster the beta-subunit gene is located upstream from the alpha-subunit gene. Filter hybridizations with phycocyanin-specific probes to total RNA detected at least two major transcripts that were 1,300 to 1,400 nucleotides long. Besides these major mRNA species, two...

  2. zeta-COP, a subunit of coatomer, is required for COP-coated vesicle assembly

    OpenAIRE

    1993-01-01

    cDNA encoding the 20-kD subunit of coatomer, zeta-COP, predicts a protein of 177-amino acid residues, similar in sequence to AP17 and AP19, subunits of the clathrin adaptor complexes. Polyclonal antibody directed to zeta-COP blocks the binding of coatomer to Golgi membranes and prevents the assembly of COP-coated vesicles on Golgi cisternae. Unlike other coatomer subunits (beta-, beta'-, gamma-, and epsilon- COP), zeta-COP exists in both coatomer bound and free pools.

  3. Mutations in G protein beta subunits promote transformation and kinase inhibitor resistance

    OpenAIRE

    Yoda, Akinori; Adelmant, Guillaume; Tamburini, Jerome; Chapuy, Bjoern; Shindoh, Nobuaki; Yoda, Yuka; Weigert, Oliver; Kopp, Nadja; Wu, Shuo-chieh; Kim, Sunhee S.; Liu, Huiyun; Tivey, Trevor; Christie, Amanda L.; Elpek, Kutlu G; Card, Joseph

    2014-01-01

    Activating mutations of G protein alpha subunits (Gα) occur in 4–5% of all human cancers 1 but oncogenic alterations in beta subunits (Gβ) have not been defined. Here we demonstrate that recurrent mutations in the Gβ proteins GNB1 and GNB2 confer cytokine-independent growth and activate canonical G protein signaling. Multiple mutations in GNB1 affect the protein interface that binds Gα subunits as well as downstream effectors, and disrupt Gα-Gβγ interactions. Different mutations in Gβ protein...

  4. Amino acid sequence of the beta subunit of bovine lung casein kinase II.

    OpenAIRE

    Takio, K.; Kuenzel, E A; Walsh, K. A.; Krebs, E G

    1987-01-01

    The amino acid sequence of the 209-residue beta subunit of bovine lung casein kinase II has been determined. Excluding the amino-terminal blocking group, which was not identified, the molecular weight of the polypeptide chain is 24,239. A marked polarity of the beta subunit is indicated by clusters of negative charges in the amino-terminal region and of positive charges in the carboxyl-terminal region. Whereas the beta subunit shows no homology with any known protein, a segment of the sequenc...

  5. Asymmetric expression of protein kinase CK2 subunits in human kidney tumors

    DEFF Research Database (Denmark)

    Stalter, G; Siemer, S; Becht, E; Ziegler, M; Remberger, K; Issinger, O G

    1994-01-01

    of protein kinase CK2 alpha in tumors/normal tissue (T/N) was 1.58 and that of the protein kinase CK2 beta (T/N) was 2.65. The data suggest that the generally described increase in protein kinase CK2 activity in tumor cells may to some extent result from a deregulation in subunit biosynthesis or...... degradation. This at least partly owing to the presence of excess enzymatically active protein kinase alpha-subunit but also to a significantly higher presence of the non-catalytic beta-subunit....

  6. Optimized polypeptide for a subunit vaccine against avian reovirus.

    Science.gov (United States)

    Goldenberg, Dana; Lublin, Avishai; Rosenbluth, Ezra; Heller, E Dan; Pitcovski, Jacob

    2016-06-01

    Avian reovirus (ARV) is a disease-causing agent. The disease is prevented by vaccination with a genotype-specific vaccine while many variants of ARV exist in the field worldwide. Production of new attenuated vaccines is a long-term process and in the case of fast-mutating viruses, an impractical one. In the era of molecular biology, vaccines may be produced by using only the relevant protein for induction of neutralizing antibodies, enabling fast adjustment to the emergence of new genetic strains. Sigma C (SC) protein of ARV is a homotrimer that facilitates host-cell attachment and induce the production and secretion of neutralizing antibodies. The aim of this study was to identify the region of SC that will elicit a protective immune response. Full-length (residues 1-326) and two partial fragments of SC (residues 122-326 and 192-326) were produced in Escherichia coli. The SC fragment of residues 122-326 include the globular head, shaft and hinge domains, while eliminating intra-capsular region. This fragment induces significantly higher levels of anti-ARV antibodies than the shorter fragment or full length SC, which neutralized embryos infection by the virulent strain to a higher extent compared with the antibodies produced in response to the whole virus vaccine. Residues 122-326 fragment is assumed to be folded correctly, exposing linear as well as conformational epitopes that are identical to those of the native protein, while possibly excluding suppressor sequences. The results of this study may serve for the development of a recombinant subunit vaccine for ARV. PMID:27155492

  7. P. berghei telomerase subunit TERT is essential for parasite survival.

    Directory of Open Access Journals (Sweden)

    Agnieszka A Religa

    Full Text Available Telomeres define the ends of chromosomes protecting eukaryotic cells from chromosome instability and eventual cell death. The complex regulation of telomeres involves various proteins including telomerase, which is a specialized ribonucleoprotein responsible for telomere maintenance. Telomeres of chromosomes of malaria parasites are kept at a constant length during blood stage proliferation. The 7-bp telomere repeat sequence is universal across different Plasmodium species (GGGTTT/CA, though the average telomere length varies. The catalytic subunit of telomerase, telomerase reverse transcriptase (TERT, is present in all sequenced Plasmodium species and is approximately three times larger than other eukaryotic TERTs. The Plasmodium RNA component of TERT has recently been identified in silico. A strategy to delete the gene encoding TERT via double cross-over (DXO homologous recombination was undertaken to study the telomerase function in P. berghei. Expression of both TERT and the RNA component (TR in P. berghei blood stages was analysed by Western blotting and Northern analysis. Average telomere length was measured in several Plasmodium species using Telomere Restriction Fragment (TRF analysis. TERT and TR were detected in blood stages and an average telomere length of ∼ 950 bp established. Deletion of the tert gene was performed using standard transfection methodologies and we show the presence of tert- mutants in the transfected parasite populations. Cloning of tert- mutants has been attempted multiple times without success. Thorough analysis of the transfected parasite populations and the parasite obtained from extensive parasite cloning from these populations provide evidence for a so called delayed death phenotype as observed in different organisms lacking TERT. The findings indicate that TERT is essential for P. berghei cell survival. The study extends our current knowledge on telomere biology in malaria parasites and validates further

  8. Elongated polyproline motifs facilitate enamel evolution through matrix subunit compaction.

    Directory of Open Access Journals (Sweden)

    Tianquan Jin

    2009-12-01

    Full Text Available Vertebrate body designs rely on hydroxyapatite as the principal mineral component of relatively light-weight, articulated endoskeletons and sophisticated tooth-bearing jaws, facilitating rapid movement and efficient predation. Biological mineralization and skeletal growth are frequently accomplished through proteins containing polyproline repeat elements. Through their well-defined yet mobile and flexible structure polyproline-rich proteins control mineral shape and contribute many other biological functions including Alzheimer's amyloid aggregation and prolamine plant storage. In the present study we have hypothesized that polyproline repeat proteins exert their control over biological events such as mineral growth, plaque aggregation, or viscous adhesion by altering the length of their central repeat domain, resulting in dramatic changes in supramolecular assembly dimensions. In order to test our hypothesis, we have used the vertebrate mineralization protein amelogenin as an exemplar and determined the biological effect of the four-fold increased polyproline tandem repeat length in the amphibian/mammalian transition. To study the effect of polyproline repeat length on matrix assembly, protein structure, and apatite crystal growth, we have measured supramolecular assembly dimensions in various vertebrates using atomic force microscopy, tested the effect of protein assemblies on crystal growth by electron microscopy, generated a transgenic mouse model to examine the effect of an abbreviated polyproline sequence on crystal growth, and determined the structure of polyproline repeat elements using 3D NMR. Our study shows that an increase in PXX/PXQ tandem repeat motif length results (i in a compaction of protein matrix subunit dimensions, (ii reduced conformational variability, (iii an increase in polyproline II helices, and (iv promotion of apatite crystal length. Together, these findings establish a direct relationship between polyproline tandem

  9. Nuclear Export and Centrosome Targeting of the Protein Phosphatase 2A Subunit B56α: ROLE OF B56α IN NUCLEAR EXPORT OF THE CATALYTIC SUBUNIT*

    OpenAIRE

    Flegg, Cameron P.; Sharma, Manisha; Medina-Palazon, Cahora; Jamieson, Cara; Galea, Melanie; Brocardo, Mariana G.; Mills, Kate; Henderson, Beric R.

    2010-01-01

    Protein phosphatase (PP) 2A is a heterotrimeric enzyme regulated by specific subunits. The B56 (or B′/PR61/PPP2R5) class of B-subunits direct PP2A or its substrates to different cellular locations, and the B56α, -β, and -ϵ isoforms are known to localize primarily in the cytoplasm. Here we studied the pathways that regulate B56α subcellular localization. We detected B56α in the cytoplasm and nucleus, and at the nuclear envelope and centrosomes, and show that cytoplasmic localization is depende...

  10. Genetic Analysis of the Mode of Interplay between an ATPase Subunit and Membrane Subunits of the Lipoprotein-Releasing ATP-Binding Cassette Transporter LolCDE†

    OpenAIRE

    Ito, Yasuko; Matsuzawa, Hitomi; Matsuyama, Shin-ichi; Narita, Shin-ichiro; Tokuda, Hajime

    2006-01-01

    The LolCDE complex, an ATP-binding cassette (ABC) transporter, releases lipoproteins from the inner membrane, thereby initiating lipoprotein sorting to the outer membrane of Escherichia coli. The LolCDE complex is composed of two copies of an ATPase subunit, LolD, and one copy each of integral membrane subunits LolC and LolE. LolD hydrolyzes ATP on the cytoplasmic side of the inner membrane, while LolC and/or LolE recognize and release lipoproteins anchored to the periplasmic leaflet of the i...

  11. Localized reconstruction of subunits from electron cryomicroscopy images of macromolecular complexes.

    Science.gov (United States)

    Ilca, Serban L; Kotecha, Abhay; Sun, Xiaoyu; Poranen, Minna M; Stuart, David I; Huiskonen, Juha T

    2015-01-01

    Electron cryomicroscopy can yield near-atomic resolution structures of highly ordered macromolecular complexes. Often however some subunits bind in a flexible manner, have different symmetry from the rest of the complex, or are present in sub-stoichiometric amounts, limiting the attainable resolution. Here we report a general method for the localized three-dimensional reconstruction of such subunits. After determining the particle orientations, local areas corresponding to the subunits can be extracted and treated as single particles. We demonstrate the method using three examples including a flexible assembly and complexes harbouring subunits with either partial occupancy or mismatched symmetry. Most notably, the method allows accurate fitting of the monomeric RNA-dependent RNA polymerase bound at the threefold axis of symmetry inside a viral capsid, revealing for the first time its exact orientation and interactions with the capsid proteins. Localized reconstruction is expected to provide novel biological insights in a range of challenging biological systems. PMID:26534841

  12. Research and design of a production system for a Tuberculosis (TB) sub-unit vaccine

    OpenAIRE

    Hunter, Georgina

    2015-01-01

    Undergraduate research project into a new Tuberculosis vaccine for those living in endemic parts of sub-Saharan Africa through the design, process development and commercial manufacture of sub-unit vaccine process engineering and manufacturing systems.

  13. Positive modulation of delta-subunit containing GABAA receptors in mouse neurons

    DEFF Research Database (Denmark)

    Vardya, Irina; Hoestgaard-Jensen, Kirsten; Nieto-Gonzalez, Jose Luis;

    2012-01-01

    δ-subunit containing extrasynaptic GABA(A) receptors are potential targets for modifying neuronal activity in a range of brain disorders. With the aim of gaining more insight in synaptic and extrasynaptic inhibition, we used a new positive modulator, AA29504, of δ-subunit containing GABA(A) recep......δ-subunit containing extrasynaptic GABA(A) receptors are potential targets for modifying neuronal activity in a range of brain disorders. With the aim of gaining more insight in synaptic and extrasynaptic inhibition, we used a new positive modulator, AA29504, of δ-subunit containing GABA......-free environment using Ca²⁺ imaging in cultured neurons, AA29504 showed GABA(A) receptor agonism in the absence of agonist. Finally, AA29504 exerted dose-dependent stress-reducing and anxiolytic effects in mice in vivo. We propose that AA29504 potentiates δ-containing GABA(A) receptors to enhance tonic inhibition...

  14. Is There an Optimal Formulation and Delivery Strategy for Subunit Vaccines?

    Science.gov (United States)

    Bobbala, Sharan; Hook, Sarah

    2016-09-01

    Modern vaccine design has moved away from attenuated or inactivated whole-pathogen vaccines to more pure and defined subunit vaccines. However subunit antigens have poor bioavailability and stability and lack immunogenicity. To overcome these issues subunit vaccines have to be administered in a suitable delivery system in combination with immune stimulants. Many different delivery systems have been developed and investigated each having different modes of action, for example increasing delivery and/or sustaining delivery of antigen to immune cells. In addition a number of different routes of immunization are possible and these can play a crucial role in determining the fate of an immune response. In this review the different strategies for the delivery of prophylactic and therapeutic subunit vaccines along with the impact of these on the immune responses generated are discussed. PMID:27380191

  15. The subunit composition of hinokiresinol synthase controls geometrical selectivity in norlignan formation.

    Science.gov (United States)

    Suzuki, Shiro; Yamamura, Masaomi; Hattori, Takefumi; Nakatsubo, Tomoyuki; Umezawa, Toshiaki

    2007-12-26

    The selective formation of E- or Z-isomers is an important process in natural product metabolism. We show that the subunit composition of an enzyme can alter the geometrical composition of the enzymatic products. Hinokiresinol synthase, purified from Asparagus officinalis cell cultures, is responsible for the conversion of (7E,7'E)-4-coumaryl 4-coumarate to (Z)-hinokiresinol, the first step in norlignan formation. The protein is most likely a heterodimer composed of two distinct subunits, which share identity with members of the phloem protein 2 gene superfamily. Interestingly, each recombinant subunit of hinokiresinol synthase expressed in Escherichia coli solely converted (7E,7'E)-4-coumaryl 4-coumarate to the unnatural (E)-hinokiresinol, the E-isomer of (Z)-hinokiresinol. By contrast, a mixture of recombinant subunits catalyzed the formation of (Z)-hinokiresinol from the same substrate. PMID:18093914

  16. Stereocontrolled Synthesis of the C(1)-C(11) Subunit of the Iejimalides

    DEFF Research Database (Denmark)

    Mendlik, Matthew T.; Cottard, Muriel; Rein, Tobias;

    1997-01-01

    An enantioselective synthesis of the C(1)-C(11) subunit of the iejimalides has been accomplished through a combination of an asymmetric Homer-Wadsworth-Emmons condensation and a chiral pool approach. (C) 1997 Elsevier Science Ltd....

  17. Performance of information system implementation based on coupling-cohesion among subunits

    Institute of Scientific and Technical Information of China (English)

    Wang Tienan; Li Yijun; Wang Mingzhu

    2007-01-01

    The intermediate information system benefit and the coupling-cohesion of subunits are presented to study the performance of information system implementation. Based on the organizational information processing theory and the organizational behaviour theory, a theoretical model is established from the perspective of coupling-cohesion of subunits. The reliability and validity of the model are checked up with the structural equation models and the data collected with questionnaires. The results of the study give some theoretical and practical guidance.

  18. Structure and Catalysis of Acylaminoacyl Peptidase CLOSED AND OPEN SUBUNITS OF A DIMER OLIGOPEPTIDASE

    OpenAIRE

    Harmat, V.; Domokos, K.; Menyhard, D. K.; Pallo, A.; Szeltner, Z.; Szamosi, I.; Beke-Somfai, T.; Naray-Szabo, G.; Polgar, L.

    2011-01-01

    Acylaminoacyl peptidase from Aeropyrum pernix is a homodimer that belongs to the prolyl oligopeptidase family. The monomer subunit is composed of one hydrolase and one propeller domain. Previous crystal structure determinations revealed that the propeller domain obstructed the access of substrate to the active site of both subunits. Here we investigated the structure and the kinetics of two mutant enzymes in which the aspartic acid of the catalytic triad was changed to alanine or asparagine. ...

  19. Phosphorylation of the C-terminal domain of the largest subunit of RNA polymerase II

    International Nuclear Information System (INIS)

    Eukaryotic RNA polymerase II consists of three subspecies, designated II0, II/sub A/, and II/sub B/, which differ in the apparent M/sub r/ of their largest subunit, IIo, IIa, and IIb, respectively. Subunits IIo, IIa, and IIb are the products of a single gene. Subunit IIa (IIo) has been shown to contain an unusual C-terminal domain composed of 52 repeats of a seven amino acid block with the consensus sequence tyr-ser-pro-thr-ser-pro-ser. In an effort to purify the C-terminal domain, purified calf thymus RNA polymerase II was cleaved with CNBr. Following SDS polyacrylamide gel electrophoresis the CNBr digests were transferred and probed with IIa mono-specific antibody. A single immunoreactive peptide with an apparent M/sub r/ of 65,000 was detected. A peptide of similar M/sub r/ was found when purified subunit IIa was digested with CNBr while no immunoreactive peptide was detected in digests of subunit IIb. Purified RNA polymerase II was phosphorylated with γ[32P]-ATP in the presence of casein kinase I and 32P-labeled subunits IIa and IIo purified. CNBr clIIa revealed a major phosphopeptide with an apparent M/sub r/ of 65,000. Cleavage of 32P-labeled age of IIo revealed a broad phosphopeptide band of M/sub r/ 75,000-90,000. The C-terminal peptide from subunit IIa was purified by gel filtration on HPLC. Experiments are in progress to map in vivo phosphorylation sites within subunits IIo and IIa and to examine the effects of the purified C-terminal peptide on in vitro transcription

  20. Phosphorylation of the C-terminal domain of the largest subunit of RNA polymerase II

    Energy Technology Data Exchange (ETDEWEB)

    Cadena, D.; Dahmus, M.E.

    1986-05-01

    Eukaryotic RNA polymerase II consists of three subspecies, designated II/sub 0/, II/sub A/, and II/sub B/, which differ in the apparent M/sub r/ of their largest subunit, IIo, IIa, and IIb, respectively. Subunits IIo, IIa, and IIb are the products of a single gene. Subunit IIa (IIo) has been shown to contain an unusual C-terminal domain composed of 52 repeats of a seven amino acid block with the consensus sequence tyr-ser-pro-thr-ser-pro-ser. In an effort to purify the C-terminal domain, purified calf thymus RNA polymerase II was cleaved with CNBr. Following SDS polyacrylamide gel electrophoresis the CNBr digests were transferred and probed with IIa mono-specific antibody. A single immunoreactive peptide with an apparent M/sub r/ of 65,000 was detected. A peptide of similar M/sub r/ was found when purified subunit IIa was digested with CNBr while no immunoreactive peptide was detected in digests of subunit IIb. Purified RNA polymerase II was phosphorylated with ..gamma..(/sup 32/P)-ATP in the presence of casein kinase I and /sup 32/P-labeled subunits IIa and IIo purified. CNBr clIIa revealed a major phosphopeptide with an apparent M/sub r/ of 65,000. Cleavage of /sup 32/P-labeled age of IIo revealed a broad phosphopeptide band of M/sub r/ 75,000-90,000. The C-terminal peptide from subunit IIa was purified by gel filtration on HPLC. Experiments are in progress to map in vivo phosphorylation sites within subunits IIo and IIa and to examine the effects of the purified C-terminal peptide on in vitro transcription.

  1. Mediator Complex Regulates Alternative mRNA Processing via the Med23 Subunit

    OpenAIRE

    Yan HUANG; Li, Wencheng; Yao, Xiao; Lin, Qi-jiang; Yin, Jing-wen; Liang, Yan; Heiner, Monika; Tian, Bin; HUI, JINGYI; Wang, Gang

    2012-01-01

    Mediator complex is an integrative hub for transcriptional regulation. Here we show that Mediator regulates alternative mRNA processing via its Med23 subunit. Combining tandem affinity purification and mass spectrometry, we identified a number of mRNA processing factors that bind to a soluble recombinant Mediator subunit MED23 but not to several other Mediator components. One of these factors, hnRNP L, specifically interacts with MED23 in vitro and in vivo. Consistently, Mediator partially co...

  2. Oxygen influences the subunit structure of cytochrome c oxidase in the slime mold Dictyostelium discoideum.

    OpenAIRE

    Schiavo, G; Bisson, R

    1989-01-01

    The conditions that promote the alternative expression of two nuclear-encoded subunits of cytochrome c oxidase in the slime mold Dictyostelium discoideum (Bisson, R., and Schiavo, G. (1986) J. Biol. Chem. 261, 4373-4376) have been investigated. Oxygen concentration seems to be the only factor able to cause the subunit switching. This result indicates that the polypeptide composition of the mitochondrial enzyme can be influenced by environmental conditions. The significance of this change is d...

  3. Nicotinic acetylcholine receptor: subunit structure, functional binding sites, and ion transport properties

    International Nuclear Information System (INIS)

    The structure of the nicotinic acetylcholine receptor has been highly conserved during animal evolution, and in all the species and tissues studied so far, including mammals, it is a pseudosymmetric, pentameric complex of related subunits with very similar physical properties. All subunits of these nicotinic receptors were derived from a common ancestral gene, probably by way of gene duplications occurring very early in animal evolution. 45 refs., 8 figs., 2 tabs

  4. Differential Distribution of Exosome Subunits at the Nuclear Lamina and in Cytoplasmic FociD⃞V⃞

    OpenAIRE

    Graham, Amy C.; Kiss, Daniel L.; Andrulis, Erik D.

    2006-01-01

    The exosome complex plays important roles in RNA processing and turnover. Despite significant mechanistic insight into exosome function, we still lack a basic understanding of the subcellular locales where exosome complex biogenesis and function occurs. Here, we employ a panel of Drosophila S2 stable cell lines expressing epitope-tagged exosome subunits to examine the subcellular distribution of exosome complex components. We show that tagged Drosophila exosome subunits incorporate into compl...

  5. Overexpression of ??3/??5/??4 nicotinic receptor subunits modifies impulsive-like behavior

    OpenAIRE

    Vi??als, Xavier; Molas Casacuberta, Susanna, 1985-; Gallego, Xavier; Fern??ndez Montes, Rub??n D.; Robledo, Patr??cia, 1958-; Dierssen, Mara; Maldonado, Rafael

    2012-01-01

    Recent studies have revealed that sequence variants in genes encoding the ??3/??5/??4 nicotinic acetylcholine receptor subunits are associated with nicotine dependence. In this study, we evaluated two specific aspects of executive functioning related to drug addiction (impulsivity and working memory) in transgenic mice over expressing ??3/??5/??4 nicotinic receptor subunits. Impulsivity and working memory were evaluated in an operant delayed alternation task, where mice must inhibit respondin...

  6. EFFECTS OF MUTANT DROSOPHILA K+ CHANNEL SUBUNITS ON HABITUATION OF THE OLFACTORY JUMP RESPONSE

    OpenAIRE

    Joiner, M. A.; ASZTALOS, Z.; Jones, C. J.; Tully, T.; Wu, C.-F.

    2007-01-01

    The olfactory-jump response assay was used to analyze habituation in Drosophila mutants of potassium (K+) channel subunits. As with physiological assays of the giant fiber-mediated escape reflex, mutations at loci that encode K+ channel subunits have distinct effects on habituating the olfactory-jump response. The data for slowpoke and ether à go-go indicate similar effects on habituation of the olfactory-jump response and the giant fiber-mediated escape. Habituation in the olfactory jump ass...

  7. Effects of the α subunit on imidacloprid sensitivity of recombinant nicotinic acetylcholine receptors

    OpenAIRE

    Matsuda, K; Buckingham, S D; Freeman, J.C.; Squire, M D; Baylis, H. A.; Sattelle, D B

    1998-01-01

    Imidacloprid is a new insecticide with selective toxicity for insects over vertebrates. Recombinant (α4β2) chicken neuronal nicotinic acetylcholine receptors (AChRs) and a hybrid nicotinic AChR formed by co-expression of a Drosophila melanogaster neuronal α subunit (SAD) with the chicken β2 subunit were heterologously expressed in Xenopus oocytes by nuclear injection of cDNAs. The agonist actions of imidacloprid and other nicotinic AChR ligands ((+)-epibatidine, (−)-nicotine and acetylcholine...

  8. Role of desensitization and subunit expression for kainate receptor-mediated neurotoxicity in murine neocortical cultures

    DEFF Research Database (Denmark)

    Jensen, J B; Schousboe, A; Pickering, D S;

    1999-01-01

    The neurotoxic actions of kainate and domoate were studied in cultured murine neocortical neurons at various days in culture and found to be developmentally regulated involving three components of neurotoxicity: (1) toxicity via indirect activation of N-methyl-D-aspartate (NMDA) receptors, (2) to...... produced by kainate receptors in mature cultures. Examining the subunit expression of the kainate receptor subunits GluR6/7 and KA2 did, however, not reveal any major change during development of the cultures....

  9. Subunit interactions and protein stability in the cyanobacterial light-harvesting proteins.

    OpenAIRE

    Plank, T; Toole, C; Anderson, L K

    1995-01-01

    Strain 4R is a phycocyanin-minus mutant of the unicellular cyanobacterium Synechocystis sp. strain 6803. Although it lacks the light-harvesting protein phycocyanin, 4R has normal levels of phycocyanin (cpc) transcripts. Sequence analysis of the cpcB gene encoding the phycocyanin beta subunit shows an insertion mutation in 4R that causes early termination of translation. Other work has shown that the phycocyanin alpha subunit and the linker proteins encoded on the cpc transcripts are all funct...

  10. Neutron scattering and the 30 S ribosomal subunit of E. coli

    International Nuclear Information System (INIS)

    This paper reviews the progress made in the study of the internal organization of the 30 S ribosomal subunit of E. coli by neutron scattering since 1975. A map of that particle showing the position of 14 of the subunit's 21 proteins is presented, and the methods currently used for collecting and analyzing such data are discussed. Also discussed is the possibility of extending the interpretation of neutron mapping data beyond the limits practical today. 30 references, 5 figures

  11. Pharmacological consequences of the coexpression of BK channel α and auxiliary β subunits

    Science.gov (United States)

    Torres, Yolima P.; Granados, Sara T.; Latorre, Ramón

    2014-01-01

    Coded by a single gene (Slo1, KCM) and activated by depolarizing potentials and by a rise in intracellular Ca2+ concentration, the large conductance voltage- and Ca2+-activated K+ channel (BK) is unique among the superfamily of K+ channels. BK channels are tetramers characterized by a pore-forming α subunit containing seven transmembrane segments (instead of the six found in voltage-dependent K+ channels) and a large C terminus composed of two regulators of K+ conductance domains (RCK domains), where the Ca2+-binding sites reside. BK channels can be associated with accessory β subunits and, although different BK modulatory mechanisms have been described, greater interest has recently been placed on the role that the β subunits may play in the modulation of BK channel gating due to its physiological importance. Four β subunits have currently been identified (i.e., β1, β2, β3, and β4) and despite the fact that they all share the same topology, it has been shown that every β subunit has a specific tissue distribution and that they modify channel kinetics as well as their pharmacological properties and the apparent Ca2+ sensitivity of the α subunit in different ways. Additionally, different studies have shown that natural, endogenous, and synthetic compounds can modulate BK channels through β subunits. Considering the importance of these channels in different pathological conditions, such as hypertension and neurological disorders, this review focuses on the mechanisms by which these compounds modulate the biophysical properties of BK channels through the regulation of β subunits, as well as their potential therapeutic uses for diseases such as those mentioned above. PMID:25346693

  12. An interaction between gramicidin and the sigma subunit of RNA polymerase.

    OpenAIRE

    Fisher, R.; Blumenthal, T

    1982-01-01

    Gramicidin, a peptide antibiotic produced by Bacillus brevis, inhibits initiation of transcription by RNA polymerase (nucleosidetriphosphate:RNA nucleotidyltransferase, EC 2.7.7.6). We show here that the presence of gramicidin causes an increase in the rate of cleavage of the sigma subunit of Escherichia coli RNA polymerase by trypsin, although it does not alter the cleavage rate of any of the core subunits. Furthermore, whereas isolated sigma is cleaved much faster than is sigma in holoenzym...

  13. Proteolytic activity of the purified hormone-binding subunit in the estrogen receptor.

    OpenAIRE

    Molinari, A M; Abbondanza, C; Armetta, I.; Medici, N; Minucci, S; Moncharmont, B; Nigro, V; Puca, G A

    1991-01-01

    The hormone-binding subunit of the calf uterus estradiol receptor was purified as a hormone-free molecule. Immunoaffinity chromatography with a specific monoclonal antibody was used as the final step. The purified subunit was specifically labeled by radioactive diisopropyl fluorophosphate. The diisopropyl fluorophosphate-labeled amino acid was serine. The purified receptor was able to release the fluorogenic or chromogenic group from synthetic peptides containing phenylalanine at the carboxyl...

  14. Neutron Scattering and the 30 S Ribosomal Subunit of E. Coli

    Science.gov (United States)

    Moore, P. B.; Engelman, D. M.; Langer, J. A.; Ramakrishnan, V. R.; Schindler, D. G.; Schoenborn, B. P.; Sillers, I. Y.; Yabuki, S.

    1982-06-01

    This paper reviews the progress made in the study of the internal organization of the 30 S ribosomal subunit of E. coli by neutron scattering since 1975. A map of that particle showing the position of 14 of the subunit's 21 proteins is presented, and the methods currently used for collecting and analyzing such data are discussed. Also discussed is the possibility of extending the interpretation of neutron mapping data beyond the limits practical today.

  15. AMPA Receptors Commandeer an Ancient Cargo Exporter for Use as an Auxiliary Subunit for Signaling

    OpenAIRE

    Nadine Harmel; Barbara Cokic; Gerd Zolles; Henrike Berkefeld; Veronika Mauric; Bernd Fakler; Valentin Stein; Nikolaj Klöcker

    2012-01-01

    Fast excitatory neurotransmission in the mammalian central nervous system is mainly mediated by ionotropic glutamate receptors of the AMPA subtype (AMPARs). AMPARs are protein complexes of the pore-lining alpha-subunits GluA1-4 and auxiliary beta-subunits modulating their trafficking and gating. By a proteomic approach, two homologues of the cargo exporter cornichon, CNIH-2 and CNIH-3, have recently been identified as constituents of native AMPARs in mammalian brain. In heterologous reconstit...

  16. Exposing the subunit diversity within protein complexes: a mass spectrometry approach.

    Science.gov (United States)

    Rozen, Shelly; Tieri, Alessandra; Ridner, Gabriela; Stark, Ann-Kathrin; Schmaler, Tilo; Ben-Nissan, Gili; Dubiel, Wolfgang; Sharon, Michal

    2013-03-01

    Identifying the list of subunits that make up protein complexes constitutes an important step towards understanding their biological functions. However, such knowledge alone does not reveal the full complexity of protein assemblies, as each subunit can take on multiple forms. Proteins can be post-translationally modified or cleaved, multiple products of alternative splicing can exist, and a single subunit may be encoded by more than one gene. Thus, for a complete description of a protein complex, it is necessary to expose the diversity of its subunits. Adding this layer of information is an important step towards understanding the mechanisms that regulate the activity of protein assemblies. Here, we describe a mass spectrometry-based approach that exposes the array of protein variants that comprise protein complexes. Our method relies on denaturing the protein complex, and separating its constituent subunits on a monolithic column prepared in-house. Following the subunit elution from the column, the flow is split into two fractions, using a Triversa NanoMate robot. One fraction is directed straight into an on-line ESI-QToF mass spectrometer for intact protein mass measurements, while the rest of the flow is fractionated into a 96-well plate for subsequent proteomic analysis. The heterogeneity of subunit composition is then exposed by correlating the subunit sequence identity with the accurate mass. Below, we describe in detail the methodological setting of this approach, its application on the endogenous human COP9 signalosome complex, and the significance of the method for structural mass spectrometry analysis of intact protein complexes. PMID:23296018

  17. A new low resolution model for the 50S subunit of Escherichia coli ribosomes

    International Nuclear Information System (INIS)

    Neutron low angle scattering studies of the 50S subunit of Escherichia coli ribosomes using the contrast variation method reveals large fluctuations in the scattering density. A region of relatively low scattering density, rich in proteins, surrounds an RNA-rich core of higher scattering density. The centres of mass of the RNA and protein parts of the 50S subunit are separated by a distance that is considerably smaller than that reported in previous studies. (orig.)

  18. Xanthan Gum as an Adjuvant in a Subunit Vaccine Preparation against Leptospirosis

    OpenAIRE

    Bacelo, Katia L.; Hartwig, Daiane D.; Seixas, Fabiana K.; Rodrigo Schuch; Angelita da S. Moreira; Marta Amaral; Tiago Collares; Vendrusculo, Claire T.; McBride, Alan J. A.; Dellagostin, Odir A.

    2014-01-01

    Leptospiral immunoglobulin-like (Lig) proteins are of great interest due to their ability to act as mediators of pathogenesis, serodiagnostic antigens, and immunogens. Purified recombinant LigA protein is the most promising subunit vaccine candidate against leptospirosis reported to date, however, as purified proteins are weak immunogens the use of a potent adjuvant is essential for the success of LigA as a subunit vaccine. In the present study, we compared xanthan pv. pruni (strain 106), alu...

  19. Investigation of molluscan phylogeny using large-subunit and small-subunit nuclear rRNA sequences.

    Science.gov (United States)

    Passamaneck, Yale J; Schander, Christoffer; Halanych, Kenneth M

    2004-07-01

    The Mollusca represent one of the most morphologically diverse animal phyla, prompting a variety of hypotheses on relationships between the major lineages within the phylum based upon morphological, developmental, and paleontological data. Analyses of small-ribosomal RNA (SSU rRNA) gene sequence have provided limited resolution of higher-level relationships within the Mollusca. Recent analyses suggest large-subunit (LSU) rRNA gene sequences are useful in resolving deep-level metazoan relationships, particularly when combined with SSU sequence. To this end, LSU (approximately 3.5 kb in length) and SSU (approximately 2 kb) sequences were collected for 33 taxa representing the major lineages within the Mollusca to improve resolution of intraphyletic relationships. Although the LSU and combined LSU+SSU datasets appear to hold potential for resolving branching order within the recognized molluscan classes, low bootstrap support was found for relationships between the major lineages within the Mollusca. LSU+SSU sequences also showed significant levels of rate heterogeneity between molluscan lineages. The Polyplacophora, Gastropoda, and Cephalopoda were each recovered as monophyletic clades with the LSU+SSU dataset. While the Bivalvia were not recovered as monophyletic clade in analyses of the SSU, LSU, or LSU+SSU, the Shimodaira-Hasegawa test showed that likelihood scores for these results did not differ significantly from topologies where the Bivalvia were monophyletic. Analyses of LSU sequences strongly contradict the widely accepted Diasoma hypotheses that bivalves and scaphopods are closely related to one another. The data are consistent with recent morphological and SSU analyses suggesting scaphopods are more closely related to gastropods and cephalopods than to bivalves. The dataset also presents the first published DNA sequences from a neomeniomorph aplacophoran, a group considered critical to our understanding of the origin and early radiation of the Mollusca

  20. The health care needs of the physically disabled patient in a home-based care environment: Implications for the training of ancillary health care workers

    Directory of Open Access Journals (Sweden)

    Monica Springe

    2010-03-01

    Full Text Available According to existing literature, ancillary health care workers (AHCWs often do not meet the health care needs of patients with physical disabilities (physically disabled patients in a homebased environment, because of inadequate training programmes. The purpose of this research study was to explore the health care needs of physically disabled patients in long-term, home-based care in the northern suburbs of Johannesburg and, based on results, to offer recommendations for the training of AHCWs. Qualitative, exploratory, descriptive and contextual means were employed in data collection and analysis. The population consisted of eight physically disabled participants who employed an AHCW to assist them with their long-term home care. Purposive sampling was used with subsequent snowballing to identify further participants for the study. Individual interviews were conducted, where participants had to answer the questions (1‘What are your health care needs?’ and(2 ‘How should these be met?’ Data saturation was ensured, after which Tesch’s method of data analysis was followed. Three categories of health care needs were identified (1 physical health care needs, (2 interpersonal relationship needs and (3 social needs, and 12 themes were derived from these categories. These categories of health care needs should be addressed in the training of AHCWs.From the themes, recommendations were described for the training of AHCWs on the health care needs of the home-based physically disabled patients. The AHCW should assist in the adaptation of the environment to the patient’s individual needs, and should use knowledge and critical thinking skills to ensure a patient-centred care setting.

    Opsomming

    Volgens die literatuur kan assistentgesondheidsorgwerkers (AGWs, as gevolg van ontoereikende opleiding, nie altyd aan die behoeftes van fisies gestremde pasiënte in 'n tuisopset voldoen nie.Die doel van hierdie navorsingstudie was

  1. Deletion mutants of AP-1 adaptin subunits display distinct phenotypes in fission yeast.

    Science.gov (United States)

    Ma, Yan; Takeuchi, Mai; Sugiura, Reiko; Sio, Susie O; Kuno, Takayoshi

    2009-08-01

    Adaptins are subunits of the heterotetrameric (beta/mu/gamma/sigma) adaptor protein (AP) complexes that are involved in clathrin-mediated membrane trafficking. Here, we show that in Schizosaccharomyces pombe the deletion strains of each individual subunit of the AP-1 complex [Apl2 (beta), Apl4 (gamma), Apm1 (mu) and Aps1 (sigma)] caused distinct phenotypes on growth sensitivity to temperature or drugs. We also show that the Deltaapm1 and Deltaapl2 mutants displayed similar but more severe phenotypes than those of Deltaaps1 or Deltaapl4 mutants. Furthermore, the Deltaapl2Deltaaps1 and Deltaapl2Deltaapl4 double mutants displayed synthetic growth defects, whereas the Deltaaps1Deltaapl4 and Deltaapl2Deltaapm1 double mutants did not. In pull-down assay, Apm1 binds Apl2 even in the absence of Aps1 and Apl4, and Apl4 binds Aps1 even in the absence of Apm1 and Apl2. Consistently, the deletion of any subunit generally caused the disassociation of the heterotetrameric complex from endosomes, although some subunits weakly localized to endosomes. In addition, the deletion of individual subunits caused similar endosomal accumulation of v-SNARE synaptobrevin Syb1. Altogether, results suggest that the four subunits are all essential for the heterotetrameric complex formation and for the AP-1 function in exit transport from endosomes. PMID:19624755

  2. Characterization and application of a radioimmunoassay for reduced, carboxymethylated human luteinizing hormone α-subunit

    International Nuclear Information System (INIS)

    We have established a double antibody RIA using a rabbit antiserum prepared against reduced, carboxymethylated (RCXM) human LH α-subunit, with RCXM-α as tracer and standard. This antiserum did not cross-react with any native gonadotropins or subunit, and reacted only weakly with RCXM-α. A tryptic digest of RCXM α-subunit was completely reactive, while chymotryptic digestion abolished all immunoreactivity. By testing with separate tryptic fragments, the recognition site could be localized to a segment close to the amino-terminus of the peptide chain. When applied to measurement of serum and urine, an immunoreactive species, parallel to RCXM α-subunit by serial dilution, was found in concentrations of 1-2 ng/ml in serum and 3-4 ng/ml in urine. Similar levels of the immunoreactive component were found in conditions of elevated gonadotropins (e.g. pregnancy) as well as gonadotropin deficiency (panhypopituitarism and Kallmann's syndrome). After stimulation with LHRH, no rise was noted at times up to 6 h despite the fact that both LH and LH-α were elevated. The data indicate that the sequence-specific antiserum may be detecting an immunoreactive form of α-subunit of LH whose kinetics of appearance and disappearance differs from those of the native subunit

  3. Using yeast two-hybrid system to detect interactions of ATP synthase subunits from Spinacia oleracea

    Institute of Scientific and Technical Information of China (English)

    石晓冰; 魏家绵; 沈允钢

    2000-01-01

    Subunit interactions among the chloroplast ATP synthase subunits were studied using the yeast two-hybrid system. Various pairwise combinations of genes encoding a, p, y, 8 and e subunits of Spinach ATP synthase fused to the binding domain or activation domain of GAL4 DNA were introduced into yeast and then expression of a reporter gene encoding p-galactosidase was detected. Of all the combinations, that of y and e subunit genes showed the highest level of reporter gene expression, while those of a and p, a and e, p and e and p and 8 induced stable and significant reporter gene expression. The combination of 8 and e as well as that of 8 and y induced weak and unstable reporter gene expression. However, combinations of a and y, p and y and a and 8 did not induce reporter gene expression. These results suggested that specific and strong interactions between y and e, a and p, a and e, p and e and p and 8 subunits, and weak and transient interactions between 8 and e and 8 and y subunits occurred in the yeast

  4. The subunit structure of potato tuber ADPglucose pyrophosphorylase. [Solanum tuberosum L

    Energy Technology Data Exchange (ETDEWEB)

    Okita, T.W.; Nakata, P.A.; Anderson, J.M. (Washington State Univ., Pullman (USA)); Sowokinos, J. (Univ. of Minnesota, St. Paul (USA)); Morell, M.; Preiss, J. (Michigan State Univ., East Lansing (USA))

    1990-06-01

    ADPglucose pyrophosphorylase has been extensively purified from potato (Solanum tuberosum L.) tuber tissue to study its structure. By employing a modified published procedure together with Mono Q chromatography, a near homogeneous enzyme preparation was obtained with substantial improvement in enzyme yield and specific activity. In single dimensional sodium dodecyl sulfate polyacrylamide gels, the enzyme migrated as a single polypeptide band with a mobility of about 50,000 daltons. Analysis by two-dimensional polyacrylamide gel electrophoresis, however, revealed the presence of two types of subunits which could be distinguished by their slight differences in net charge and molecular weight. The smaller potato tuber subunit was recognized by antiserum prepared against the smaller spinach leaf 51 kilodalton ADPglucose pyrophosphorylase subunit. In contrast, the anti-54 kilodalton raised against the spinach leaf subunit did not significantly react to the tuber enzyme subunits. The results are consistent with the hypothesis that the potato tuber ADPglucose pyrophosphorylase is not composed of a simple homotetramer as previously suggested, but is a product of two separate and distinct subunits as observed for the spinach leaf and maize enzymes.

  5. High molecular weight glutenin subunits. A molecular marker used to estimate the quality of wheat germplasm

    International Nuclear Information System (INIS)

    Recent progress made with electrophoretic separation of glutenin subunits, their genetics and their implication on breadmaking quality offers the possibility of performing indirect selection for quality using glutenin subunits whose expression is perigenetically independent. The composition of the glutenin subunits (with a high molecular weight) of 15 genotypes representative of the germplasm grown recently in Romania was analysed by electrophoresis in 15% polyacrylamide gel with SDS; eight proteinogram types were established. The average technological indices for 3 years were used to determine the correlations and linear regressions of the different indices and to score the glutenin composition. The glutenin scores are presented in Fig. 1. It should be mentioned that 11 of the 15 genotypes analyzed contained subunits that have the most important effect on breadmaking quality. For Aniversar and Lovrin 41 varieties, two to three biotypes were evident. The glutenin scores correlated significantly with the loaf volume, the farino-graphic value and the sedimentation test. It was also shown that the electrophoretic method is useful in the early breeding stages because it reveals the polymorphic composition of glutenin subunits. The role of glutenin is complex, but the variation in composition of high molecular weight glutenin subunits plays an important part in determining the differences in breadmaking quality between wheat varieties. 1 ref., 1 fig., 1 tab

  6. The TCP1γ subunit of Leishmania donovani forms a biologically active homo-oligomeric complex.

    Science.gov (United States)

    Bhaskar; Mitra, Kalyan; Kuldeep, Jitendra; Siddiqi, Mohammad Imran; Goyal, Neena

    2015-12-01

    Chaperonins are a class of molecular chaperons that encapsulate nascent or stress-denatured proteins and assist their intracellular assembly and folding in an ATP-dependent manner. The ubiquitous eukaryotic chaperonin, TCP1 ring complex is a hetero-oligomeric complex comprising two rings, each formed of eight subunits that may have distinct substrate recognition and ATP hydrolysis properties. In Leishmania, only the TCP1γ subunit has been cloned and characterized. It exhibited differential expression at various growth stages of promastigotes. In the present study, we expressed the TCP1γ subunit in Escherichia coli to investigate whether it forms chaperonin-like complexes and plays a role in protein folding. LdTCP1γ formed high-molecular-weight complexes within E. coli cells as well as in Leishmania cell lysates. The recombinant protein is arranged into two back-to-back rings of seven subunits each, as predicted by homology modelling and observed by negative staining electron microscopy. This morphology is consistent with that of the oligomeric double-ring group I chaperonins found in mitochondria. The LdTCP1γ homo-oligomeric complex hydrolysed ATP, and was active as assayed by luciferase refolding. Thus, the homo-oligomer performs chaperonin reactions without partner subunit(s). Further, co-immunoprecipitation studies revealed that LdTCP1γ interacts with actin and tubulin proteins, suggesting that the complex may have a role in maintaining the structural dynamics of the cytoskeleton of parasites. PMID:26395202

  7. A protein residing at the subunit interface of the bacterial ribosome.

    Science.gov (United States)

    Agafonov, D E; Kolb, V A; Nazimov, I V; Spirin, A S

    1999-10-26

    Surface labeling of Escherichia coli ribosomes with the use of the tritium bombardment technique has revealed a minor unidentified ribosome-bound protein (spot Y) that is hidden in the 70S ribosome and becomes highly labeled on dissociation of the 70S ribosome into subunits. In the present work, the N-terminal sequence of the protein Y was determined and its gene was identified as yfia, an ORF located upstream the phe operon of E. coli. This 12.7-kDa protein was isolated and characterized. An affinity of the purified protein Y for the 30S subunit, but not for the 50S ribosomal subunit, was shown. The protein proved to be exposed on the surface of the 30S subunit. The attachment of the 50S subunit resulted in hiding the protein Y, thus suggesting the protein location at the subunit interface in the 70S ribosome. The protein was shown to stabilize ribosomes against dissociation. The possible role of the protein Y as ribosome association factor in translation is discussed. PMID:10535924

  8. The 2.3 {angstrom} crystal structure of cholera toxin B subunit pentamer: Choleragenoid

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Rong-Guang; Westbrook, M.L. [Argonne National Lab., IL (United States); Maulik, P.R.; Reed, R.A.; Shipley, G. [Boston Univ., MA (United States). School of Medicine; Westbrook, E.M. [Argonne National Lab., IL (United States)]|[Northwestern Univ., Evanston, IL (United States); Scott, D.L.; Otwinowski, Z. [Yale Univ., New Haven, CT (United States)

    1996-02-01

    Cholera toxin, a heterohexameric AB{sub 5} enterotoxin released by Vibrio cholera, induces a profuse secretory diarrhea in susceptible hosts. Choleragenoid, the B subunit pentamer of cholera toxin, directs the enzymatic A subunit to its target by binding to GM{sub 1} gangliosides exposed on the luminal surface of intestinal epithelial cells. We have solved the crystal structure of choleragenoid at 2.3 {Angstrom} resolution by combining single isomorphous replacement with non-crystallographic symmetry averaging. The structure of the B subunits, and their pentameric arrangement, closely resembles that reported for the intact holotoxin (choleragen), the heat-labile enterotoxin from E. coli, and for a choleragenoid-GM{sub 1} pentasaccharide complex. In the absence of the A subunit the central cavity of the B pentamer is a highly solvated channel. The binding of the A subunit or the receptor pentasaccharide to choleragenoid has only a modest effect on the local stereochemistry and does not perceptibly alter the subunit interface.

  9. ATP synthase of yeast mitochondria. Isolation of subunit j and disruption of the ATP18 gene.

    Science.gov (United States)

    Arnold, I; Pfeiffer, K; Neupert, W; Stuart, R A; Schägger, H

    1999-01-01

    The subunit composition of the mitochondrial ATP synthase from Saccharomyces cerevisiae was analyzed using blue native gel electrophoresis and high resolution SDS-polyacrylamide gel electrophoresis. We report here the identification of a novel subunit of molecular mass of 6,687 Da, termed subunit j (Su j). An open reading frame of 127 base pairs (ATP18), which encodes for Su j, was identified on chromosome XIII. Su j does not display sequence similarity to ATP synthase subunits from other organisms. Data base searches, however, identified a potential homolog from Schizosaccharomyces pombe with 51% identity to Su j of S. cerevisiae. Su j, a small protein of 59 amino acid residues, has the characteristics of an integral inner membrane protein with a single transmembrane segment. Deletion of the ATP18 gene encoding Su j led to a strain (Deltasu j) completely deficient in oligomycin-sensitive ATPase activity and unable to grow on nonfermentable carbon sources. The presence of Su j is required for the stable expression of subunits 6 and f of the F0 membrane sector. In the absence of Su j, spontaneously arising rho- cells were observed that lacked also ubiquinol-cytochrome c reductase and cytochrome c oxidase activities. We conclude that Su j is a novel and essential subunit of yeast ATP synthase. PMID:9867807

  10. Comparison of ventilation/perfusion scintigraphy and helical CT for diagnosis of pulmonary embolism; strategy using clinical data and ancillary findings

    International Nuclear Information System (INIS)

    Study objective: To address the question whether ventilation/perfusion scintigraphy (SCINT) or helical computed tomography (CT) should be first hand method for diagnosis of pulmonary embolism (PE). Setting: Departments of radiology, nuclear medicine and internal medicine of a large university hospital. Patients: During 3 years all 128 patients examined for suspected PE with both methods were analyzed. The strategy of interpretation behind original clinical reports, i.e. clinical CT and clinical SCINT, was based upon basic criteria for PE, ancillary findings and information from the referring doctor and from previous examinations. Reviewed SCINT and CT reports were obtained from experts in each field blinded to clinical and laboratory data. The findings with respect to PE were classified as no PE, PE or non-diagnostic. Other pathology than PE was described. A Final diagnosis serving as reference was based upon CT, SCINT and other information including clinical follow for 6-24 months. Methods: Planar SCINT was made with ventilation always preceding perfusion. CT was made with contrast injection using 3 mm collimation and table feed of 3mm/sec. Results: PE was diagnosed in 32 patients. For clinical/reviewed SCINT sensitivity was 91/97 %, specificity 96/100% and rate of non-diagnostic findings 10/9%. For clinical/reviewed CT sensitivity was 81/78%, specificity 99/100% and non-diagnostic findings was observed in 8/1%. In patients with PE concordant positive results were obtained with both modalities in 23/32 (72%). Conclusion: SCINT remains first hand method because its high sensitivity, general feasibility, low radiation burden and low rate of non-diagnostic findings in our setting. CT is indispensable when SCINT is not available or its result non-diagnostic

  11. The elusive third subunit IIa of the bacterial B-type oxidases: the enzyme from the hyperthermophile Aquifex aeolicus.

    Directory of Open Access Journals (Sweden)

    Laurence Prunetti

    Full Text Available The reduction of molecular oxygen to water is catalyzed by complicated membrane-bound metallo-enzymes containing variable numbers of subunits, called cytochrome c oxidases or quinol oxidases. We previously described the cytochrome c oxidase II from the hyperthermophilic bacterium Aquifex aeolicus as a ba(3-type two-subunit (subunits I and II enzyme and showed that it is included in a supercomplex involved in the sulfide-oxygen respiration pathway. It belongs to the B-family of the heme-copper oxidases, enzymes that are far less studied than the ones from family A. Here, we describe the presence in this enzyme of an additional transmembrane helix "subunit IIa", which is composed of 41 amino acid residues with a measured molecular mass of 5105 Da. Moreover, we show that subunit II, as expected, is in fact longer than the originally annotated protein (from the genome and contains a transmembrane domain. Using Aquifex aeolicus genomic sequence analyses, N-terminal sequencing, peptide mass fingerprinting and mass spectrometry analysis on entire subunits, we conclude that the B-type enzyme from this bacterium is a three-subunit complex. It is composed of subunit I (encoded by coxA(2 of 59000 Da, subunit II (encoded by coxB(2 of 16700 Da and subunit IIa which contain 12, 1 and 1 transmembrane helices respectively. A structural model indicates that the structural organization of the complex strongly resembles that of the ba(3 cytochrome c oxidase from the bacterium Thermus thermophilus, the IIa helical subunit being structurally the lacking N-terminal transmembrane helix of subunit II present in the A-type oxidases. Analysis of the genomic context of genes encoding oxidases indicates that this third subunit is present in many of the bacterial oxidases from B-family, enzymes that have been described as two-subunit complexes.

  12. Regulation of the Telomerase Reverse Transcriptase Subunit through Epigenetic Mechanisms

    Science.gov (United States)

    Lewis, Kayla A.; Tollefsbol, Trygve O.

    2016-01-01

    Chromosome-shortening is characteristic of normal cells, and is known as the end replication problem. Telomerase is the enzyme responsible for extending the ends of the chromosomes in de novo synthesis, and occurs in germ cells as well as most malignant cancers. There are three subunits of telomerase: human telomerase RNA (hTERC), human telomerase associated protein (hTEP1), or dyskerin, and human telomerase reverse transcriptase (hTERT). hTERC and hTEP1 are constitutively expressed, so the enzymatic activity of telomerase is dependent on the transcription of hTERT. DNA methylation, histone methylation, and histone acetylation are basic epigenetic regulations involved in the expression of hTERT. Non-coding RNA can also serve as a form of epigenetic control of hTERT. This epigenetic-based regulation of hTERT is important in providing a mechanism for reversibility of hTERT control in various biological states. These include embryonic down-regulation of hTERT contributing to aging and the upregulation of hTERT playing a critical role in over 90% of cancers. Normal human somatic cells have a non-methylated/hypomethylated CpG island within the hTERT promoter region, while telomerase-positive cells paradoxically have at least a partially methylated promoter region that is opposite to the normal roles of DNA methylation. Histone acetylation of H3K9 within the promoter region is associated with an open chromatin state such that transcription machinery has the space to form. Histone methylation of hTERT has varied control of the gene, however. Mono- and dimethylation of H3K9 within the promoter region indicate silent euchromatin, while a trimethylated H3K9 enhances gene transcription. Non-coding RNAs can target epigenetic-modifying enzymes, as well as transcription factors involved in the control of hTERT. An epigenetics diet that can affect the epigenome of cancer cells is a recent fascination that has received much attention. By combining portions of this diet with

  13. Atypical properties of a conventional calcium channel β subunit from the platyhelminth Schistosoma mansoni

    Directory of Open Access Journals (Sweden)

    Schneider Toni

    2008-03-01

    Full Text Available Abstract Background The function of voltage-gated calcium (Cav channels greatly depends on coupling to cytoplasmic accessory β subunits, which not only promote surface expression, but also modulate gating and kinetic properties of the α1 subunit. Schistosomes, parasitic platyhelminths that cause schistosomiasis, express two β subunit subtypes: a structurally conventional β subunit and a variant β subunit with unusual functional properties. We have previously characterized the functional properties of the variant Cavβ subunit. Here, we focus on the modulatory phenotype of the conventional Cavβ subunit (SmCavβ using the human Cav2.3 channel as the substrate for SmCavβ and the whole-cell patch-clamp technique. Results The conventional Schistosoma mansoni Cavβ subunit markedly increases Cav2.3 currents, slows macroscopic inactivation and shifts steady state inactivation in the hyperpolarizing direction. However, currents produced by Cav2.3 in the presence of SmCavβ run-down to approximately 75% of their initial amplitudes within two minutes of establishing the whole-cell configuration. This suppressive effect was independent of Ca2+, but dependent on intracellular Mg2+-ATP. Additional experiments revealed that SmCavβ lends the Cav2.3/SmCavβ complex sensitivity to Na+ ions. A mutant version of the Cavβ subunit lacking the first forty-six amino acids, including a string of twenty-two acidic residues, no longer conferred sensitivity to intracellular Mg2+-ATP and Na+ ions, while continuing to show wild type modulation of current amplitude and inactivation of Cav2.3. Conclusion The data presented in this article provide insights into novel mechanisms employed by platyhelminth Cavβ subunits to modulate voltage-gated Ca2+ currents that indicate interactions between the Ca2+ channel complex and chelated forms of ATP as well as Na+ ions. These results have potentially important implications for understanding previously unknown mechanisms by

  14. Dithiothreitol activation of the insulin receptor/kinase does not involve subunit dissociation of the native α2β2 insulin receptor subunit complex

    International Nuclear Information System (INIS)

    The subunit composition of the dithiothreitol- (DTT) activated insulin receptor/kinase was examined by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis and gel filtration chromatography under denaturing or nondenaturing conditions. Pretreatment of 32P-labeled insulin receptors with 50 mM DTT followed by gel filtration chromatography in 0.1% SDS demonstrated the dissociation of the α2β2 insulin receptor complex (M/sub r/ 400,000) into the monomeric 95,000 β subunit. In contrast, pretreatment of the insulin receptors with 1-50 mM DTT followed by gel filtration chromatography in 0.1% Triton X-100 resulted in no apparent alteration in mobility compared to the untreated insulin receptors. Resolution of this complex by nonreducing SDS-polyacrylamide gel electrophoresis and autoradiography demonstrated the existence of the α2β2 heterotetrameric complex with essentially no αβ heterodimeric or free monomeric β subunit species present. This suggests that the insulin receptor can reoxidize into the M/sub r/ 400,000 complex after the removal of DTT by gel filtration chromatography. To prevent reoxidation, the insulin receptors were pretreated with 50 mM DTT. Under the conditions the insulin receptors migrated as the M/sub r/ 400,000 α2β2 complex. These results demonstrate that treatment of the insulin receptors with high concentrations of DTT, followed by removal of DTT by gel filtration, results in reoxidation of the reduced α2β2 insulin receptor complex. Further, these results document that although the DTT stimulation of the insulin receptor/kinase does involve reduction of the insulin receptor subunits, it does not result in dissociation of the native α2β2 insulin receptor subunit complex

  15. The A1 Subunit of Shiga Toxin 2 Has Higher Affinity for Ribosomes and Higher Catalytic Activity than the A1 Subunit of Shiga Toxin 1.

    Science.gov (United States)

    Basu, Debaleena; Li, Xiao-Ping; Kahn, Jennifer N; May, Kerrie L; Kahn, Peter C; Tumer, Nilgun E

    2016-01-01

    Shiga toxin (Stx)-producing Escherichia coli (STEC) infections can lead to life-threatening complications, including hemorrhagic colitis (HC) and hemolytic-uremic syndrome (HUS), which is the most common cause of acute renal failure in children in the United States. Stx1 and Stx2 are AB5 toxins consisting of an enzymatically active A subunit associated with a pentamer of receptor binding B subunits. Epidemiological evidence suggests that Stx2-producing E. coli strains are more frequently associated with HUS than Stx1-producing strains. Several studies suggest that the B subunit plays a role in mediating toxicity. However, the role of the A subunits in the increased potency of Stx2 has not been fully investigated. Here, using purified A1 subunits, we show that Stx2A1 has a higher affinity for yeast and mammalian ribosomes than Stx1A1. Biacore analysis indicated that Stx2A1 has faster association and dissociation with ribosomes than Stx1A1. Analysis of ribosome depurination kinetics demonstrated that Stx2A1 depurinates yeast and mammalian ribosomes and an RNA stem-loop mimic of the sarcin/ricin loop (SRL) at a higher catalytic rate and is a more efficient enzyme than Stx1A1. Stx2A1 depurinated ribosomes at a higher level in vivo and was more cytotoxic than Stx1A1 in Saccharomyces cerevisiae. Stx2A1 depurinated ribosomes and inhibited translation at a significantly higher level than Stx1A1 in human cells. These results provide the first direct evidence that the higher affinity for ribosomes in combination with higher catalytic activity toward the SRL allows Stx2A1 to depurinate ribosomes, inhibit translation, and exhibit cytotoxicity at a significantly higher level than Stx1A1. PMID:26483409

  16. Face Recognition Incorporating Ancillary Information

    Directory of Open Access Journals (Sweden)

    Sangyoun Lee

    2007-11-01

    Full Text Available Due to vast variations of extrinsic and intrinsic imaging conditions, face recognition remained to be a challenging computer vision problem even today. This is particularly true when the passive imaging approach is considered for robust applications. To advance existing recognition systems for face, numerous techniques and methods have been proposed to overcome the almost inevitable performance degradation due to external factors such as pose, expression, occlusion, and illumination. In particular, the recent part-based method has provided noticeable room for verification performance improvement based on the localized features which have good tolerance to variation of external conditions. The part-based method, however, does not really stretch the performance without incorporation of global information from the holistic method. In view of the need to fuse the local information and the global information in an adaptive manner for reliable recognition, in this paper we investigate whether such external factors can be explicitly estimated and be used to boost the verification performance during fusion of the holistic and part-based methods. Our empirical evaluations show noticeable performance improvement adopting the proposed method.

  17. Involvement of the catalytic subunit of protein kinase A and of HA95 in pre-mRNA splicing

    International Nuclear Information System (INIS)

    Protein kinase A (PKA) is a holoenzyme consisting of two catalytic (C) subunits bound to a regulatory (R) subunit dimer. Stimulation by cAMP dissociates the holoenzyme and causes translocation to the nucleus of a fraction of the C subunit. Apart from transcription regulation, little is known about the function of the C subunit in the nucleus. In the present report, we show that both Cα and Cβ are localized to spots in the mammalian nucleus. Double immunofluorescence analysis of splicing factor SC35 with the C subunit indicated that these spots are splicing factor compartments (SFCs). Using the E1A in vivo splicing assay, we found that catalytically active C subunits regulate alternative splicing and phosphorylate several members of the SR-protein family of splicing factors in vitro. Furthermore, nuclear C subunits co-localize with the C subunit-binding protein homologous to AKAP95, HA95. HA95 also regulates E1A alternative splicing in vivo, apparently through its N-terminal domain. Localization of the C subunit to SFCs and the E1A splicing pattern were unaffected by cAMP stimulation. Our findings demonstrate that the nuclear PKA C subunit co-locates with HA95 in SFCs and regulates pre-mRNA splicing, possibly through a cAMP-independent mechanism

  18. Large-scale purification and characterization of the five subunits of F1-ATPase from pig heart mitochondria.

    Science.gov (United States)

    Gagliardi, D; Penin, F; Gautheron, D C

    1991-09-13

    A large-scale purification procedure was developed to isolate the five subunits of F1-ATPase from pig heart mitochondria. The previously described procedure (Williams, N. and Pedersen, P.L. (1986) Methods Enzymol. 126, 484-489) to dissociate the rat liver F1-ATPase by cold treatment followed by warming at 37 degrees C has been adapted for the pig heart enzyme. Removal of endogenous nucleotides from that enzyme before dissociation led to the efficient separation of the alpha and gamma subunits from beta, delta and epsilon subunits. The beta subunit was purified in the hundred-milligram range by anion-exchange chromatography in the absence of any denaturing agent. This subunit was free from any bound nucleotide and almost no ATPase and adenylate kinase-like activities were detected. The delta and epsilon subunits were purified by reversed-phase chromatography (RP-HPLC) in the milligram range. As recently reported (Penin, F., Deléage, G., Gagliardi, D., Roux, B. and Gautheron, D.C. (1990) Biochemistry 29, 9358-9364), these purified subunits kept biophysical features of folded proteins and their ability to reconstitute the tight delta epsilon complex. The alpha and gamma subunits remained poorly soluble and required dissociation by 8 M guanidinium chloride prior to their purification by RP-HPLC. In addition, characterizations of the five subunits by IEF and SDS-polyacrylamide gel electrophoresis are reported, as well as ultraviolet spectra and solubility properties of the beta, delta and epsilon subunits. PMID:1832960

  19. Activities of complete and truncated forms of pertussis toxin subunits S1 and S2 synthesized by Escherichia coli.

    Science.gov (United States)

    Locht, C; Cieplak, W; Marchitto, K S; Sato, H; Keith, J M

    1987-01-01

    The genes encoding the S1 and S2 subunits of pertussis toxin were expressed in Escherichia coli under lac operon transcription and translation control with pUC8 and pUC18 as the expression vectors. Various versions of the subunits were detected with anti-S1 or anti-S2 monoclonal antibodies. Recombinant S1, but not S2, subunit contained the enzymatic NAD-glycohydrolase and NAD:Gi ADP-ribosyltransferase activities. Both activities were also expressed by a truncated version of the S1 subunit in which the 48 carboxy-terminal amino acid residues, including a predicted Rossman structure and one of the two cysteines, had been deleted. The epitope for an anti-S2 monoclonal antibody was localized to the N-terminal 40-amino-acid region of the S2 subunit. Both the S1 and S2 subunits expressed in E. coli reacted with human hyperimmune serum. The full length and the truncated recombinant S1 subunit also reacted in Western blots with a neutralizing and protective monoclonal anti-S1 antibody. The different versions of S1 and S2 subunits expressed in E. coli are useful for mapping active sites, epitopes, and regions that interact with receptors or the other subunits in the holotoxin. These recombinant subunits will also facilitate the development of a safer, new-generation vaccine against whooping cough. Images PMID:3117686

  20. Cloning and expression of the gene encoding catalytic subunit of thermostable glucose dehydrogenase from Burkholderia cepacia in Escherichia coli.

    Science.gov (United States)

    Inose, Ken; Fujikawa, Masako; Yamazaki, Tomohiko; Kojima, Katsuhiro; Sode, Koji

    2003-02-21

    We have cloned a 1620-nucleotide gene encoding the catalytic subunit (alpha subunit) of a thermostable glucose dehydrogenase (GDH) from Burkholderia cepacia. The FAD binding motif was found in the N-terminal region of the alpha subunit. The deduced primary structure of the alpha subunit showed about 48% identity to the catalytic subunits of sorbitol dehydrogenase (SDH) from Gluconobacter oxydans and 2-keto-D-gluconate dehydrogenases (2KGDH) from Erwinia herbicola and Pantoea citrea. The alpha subunit of B. cepacia was expressed in Escherichia coli in its active water-soluble form, showing maximum dye-mediated GDH activity at 70 degrees C, retaining high thermal stability. A putative open reading frame (ORF) of 507 nucleotides was also found upstream of the alpha subunit encoding an 18-kDa peptide, designated as gamma subunit. The deduced primary structure of gamma subunit showed about 30% identity to the small subunits of the SDH from G. oxydans and 2KGDHs from E. herbicola and P. citrea. PMID:12573242

  1. Association of catalytic and regulatory subunits of cyclic AMP-dependent protein kinase requires a negatively charged side group at a conserved threonine.

    OpenAIRE

    Levin, L R; Zoller, M J

    1990-01-01

    In Saccharomyces cerevisiae, as in higher eucaryotes, cyclic AMP (cAMP)-dependent protein kinase is a tetramer composed of two catalytic (C) subunits and two regulatory (R) subunits. In the absence of cAMP, the phosphotransferase activity of the C subunit is inhibited by the tight association with R. Mutation of Thr-241 to Ala in the C1 subunit of S. cerevisiae reduces the affinity of this subunit for the R subunit approximately 30-fold and results in a monomeric cAMP-independent C subunit. T...

  2. The calcium channel β2 (CACNB2 subunit repertoire in teleosts

    Directory of Open Access Journals (Sweden)

    Mueller Rachel

    2008-04-01

    Full Text Available Abstract Background Cardiomyocyte contraction is initiated by influx of extracellular calcium through voltage-gated calcium channels. These oligomeric channels utilize auxiliary β subunits to chaperone the pore-forming α subunit to the plasma membrane, and to modulate channel electrophysiology 1. Several β subunit family members are detected by RT-PCR in the embryonic heart. Null mutations in mouse β2, but not in the other three β family members, are embryonic lethal at E10.5 due to defects in cardiac contractility 2. However, a drawback of the mouse model is that embryonic heart rhythm is difficult to study in live embryos due to their intra-uterine development. Moreover, phenotypes may be obscured by secondary effects of hypoxia. As a first step towards developing a model for contributions of β subunits to the onset of embryonic heart rhythm, we characterized the structure and expression of β2 subunits in zebrafish and other teleosts. Results Cloning of two zebrafish β2 subunit genes (β2.1 and β2.2 indicated they are membrane-associated guanylate kinase (MAGUK-family genes. Zebrafish β2 genes show high conservation with mammals within the SH3 and guanylate kinase domains that comprise the "core" of MAGUK proteins, but β2.2 is much more divergent in sequence than β2.1. Alternative splicing occurs at the N-terminus and within the internal HOOK domain. In both β2 genes, alternative short ATG-containing first exons are separated by some of the largest introns in the genome, suggesting that individual transcript variants could be subject to independent cis-regulatory control. In the Tetraodon nigrovidis and Fugu rubripes genomes, we identified single β2 subunit gene loci. Comparative analysis of the teleost and human β2 loci indicates that the short 5' exon sequences are highly conserved. A subset of 5' exons appear to be unique to teleost genomes, while others are shared with mammals. Alternative splicing is temporally and

  3. Prehospital digital photography and automated image transmission in an emergency medical service – an ancillary retrospective analysis of a prospective controlled trial

    Directory of Open Access Journals (Sweden)

    Bergrath Sebastian

    2013-01-01

    Full Text Available Abstract Background Still picture transmission was performed using a telemedicine system in an Emergency Medical Service (EMS during a prospective, controlled trial. In this ancillary, retrospective study the quality and content of the transmitted pictures and the possible influences of this application on prehospital time requirements were investigated. Methods A digital camera was used with a telemedicine system enabling encrypted audio and data transmission between an ambulance and a remotely located physician. By default, images were compressed (jpeg, 640 x 480 pixels. On occasion, this compression was deactivated (3648 x 2736 pixels. Two independent investigators assessed all transmitted pictures according to predefined criteria. In cases of different ratings, a third investigator had final decision competence. Patient characteristics and time intervals were extracted from the EMS protocol sheets and dispatch centre reports. Results Overall 314 pictures (mean 2.77 ± 2.42 pictures/mission were transmitted during 113 missions (group 1. Pictures were not taken for 151 missions (group 2. Regarding picture quality, the content of 240 (76.4% pictures was clearly identifiable; 45 (14.3% pictures were considered “limited quality” and 29 (9.2% pictures were deemed “not useful” due to not/hardly identifiable content. For pictures with file compression (n = 84 missions and without (n = 17 missions, the content was clearly identifiable in 74% and 97% of the pictures, respectively (p = 0.003. Medical reports (n = 98, 32.8%, medication lists (n = 49, 16.4% and 12-lead ECGs (n = 28, 9.4% were most frequently photographed. The patient characteristics of group 1 vs. 2 were as follows: median age – 72.5 vs. 56.5 years, p = 0.001; frequency of acute coronary syndrome – 24/113 vs. 15/151, p = 0.014. The NACA scores and gender distribution were comparable. Median on-scene times were longer with picture

  4. B vitamin and/or n-3 fatty acid supplementation and health-related quality of life: ancillary findings from the SU.FOL.OM3 randomized trial.

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    Valentina A Andreeva

    Full Text Available BACKGROUND: Despite growing attention to nutrition and quality of life in cardiovascular disease survivors, the impact of dietary factors according to disease type or to quality of life domain is poorly understood. We investigated the effects of B vitamin and/or n-3 fatty acid supplementation on health-related quality of life among survivors of stroke, myocardial infarction, or unstable angina. METHODS: We performed ancillary analyses of the SU.FOL.OM3 trial (2003-2009; France. In total, 2,501 men (mean age = 61 y and women (mean age = 63 y were randomized in a 2×2 factorial design to: 1 0.56 mg 5-methyl-tetrahydrofolate, 3 mg vitamin B6, 0.02 mg vitamin B12; 2 600 mg eicosapentaenoic and docosahexaenoic acids in a 2∶1 ratio; 3 B vitamins and n-3 fatty acids combined; or 4 placebo. Health-related quality of life was evaluated at follow-up with the Medical Outcomes Study 36-Item Short Form Health Survey. Data from 2,029 individuals were used in this analysis. RESULTS: After 3.1±0.4 y, no effects of supplementation with either B vitamins or n-3 fatty acids on quality of life (physical or mental health domains were found. However, participants receiving B vitamins had slightly more activity limitations due to emotional problems compared with those not receiving B vitamins (mean difference = 3.8; 95% CI: 0.4, 7.1. A significant interaction of treatment by prior disease revealed an inverse association between n-3 fatty acids and vitality among myocardial infarction survivors (mean difference = 2.9; 95% CI: 0.5, 5.2. CONCLUSIONS: There were no beneficial effects of supplementation with relatively low doses of B vitamins or n-3 fatty acids on health-related quality of life in cardiovascular disease survivors. The adverse effects of B vitamins on activity limitations and of n-3 fatty acids on vitality among individuals with prior myocardial infarction merit confirmation.

  5. Immunochemical characterization of two thyroid-stimulating hormone beta-subunit epitopes.

    Science.gov (United States)

    Fairlie, W D; Stanton, P G; Hearn, M T

    1995-01-01

    The epitopes of human thyroid-stimulating hormone (hTSH) recognized by two murine monoclonal antibodies (MAbs), designated MAb 279 and MAb 299, have been characterized. These MAbs are highly specific for the beta-subunit of TSH. The epitope recognized by MAb 279 appears to be completely conserved between bovine and human TSH and partially conserved in the porcine species. The TSH beta-subunit epitope recognized by MAb 299 is only partially conserved between the human, bovine and porcine species. Both MAbs are capable of inhibiting the binding of TSH to its receptor in a TSH radioreceptor assay, indicating that the epitopes either coincide or are located close to the TSH beta-subunit receptor-binding sites. The carbohydrate moieties of the TSH beta-subunit appear to play little or no role in the epitope recognition by MAb 279 or MAb 299 while the integrity of the disulphide bonds are essential. The epitopic recognition may also involve lysine residues, as determined by the immunoreactivity with both MAbs following citraconylation of TSH. In addition, the amino acid sequence region between residues bTSH beta 34-44 could be excised by trypsin digestion of bovine TSH beta (bTSH beta) without eliminating epitopic recognition by either MAb. These results provide further insight into the relationship between the structure of the TSH beta-subunit epitopes and location of the receptor-binding sites. Images Figure 2 PMID:7538754

  6. Structural analysis of the α subunit of Na(+)/K(+) ATPase genes in invertebrates.

    Science.gov (United States)

    Thabet, Rahma; Rouault, J-D; Ayadi, Habib; Leignel, Vincent

    2016-01-01

    The Na(+)/K(+) ATPase is a ubiquitous pump coordinating the transport of Na(+) and K(+) across the membrane of cells and its role is fundamental to cellular functions. It is heteromer in eukaryotes including two or three subunits (α, β and γ which is specific to the vertebrates). The catalytic functions of the enzyme have been attributed to the α subunit. Several complete α protein sequences are available, but only few gene structures were characterized. We identified the genomic sequences coding the α-subunit of the Na(+)/K(+) ATPase, from the whole-genome shotgun contigs (WGS), NCBI Genomes (chromosome), Genomic Survey Sequences (GSS) and High Throughput Genomic Sequences (HTGS) databases across distinct phyla. One copy of the α subunit gene was found in Annelida, Arthropoda, Cnidaria, Echinodermata, Hemichordata, Mollusca, Placozoa, Porifera, Platyhelminthes, Urochordata, but the nematodes seem to possess 2 to 4 copies. The number of introns varied from 0 (Platyhelminthes) to 26 (Porifera); and their localization and length are also highly variable. Molecular phylogenies (Maximum Likelihood and Maximum Parsimony methods) showed some clusters constituted by (Chordata/(Echinodermata/Hemichordata)) or (Plathelminthes/(Annelida/Mollusca)) and a basal position for Porifera. These structural analyses increase our knowledge about the evolutionary events of the α subunit genes in the invertebrates. PMID:26812300

  7. Characterization of the gene encoding the largest subunit of Plasmodium falciparum RNA polymerase III.

    Science.gov (United States)

    Li, W B; Bzik, D J; Tanaka, M; Gu, H M; Fox, B A; Inselburg, J

    1991-06-01

    We report here the isolation, sequence analysis, structure, and expression of the gene encoding the largest subunit of RNA polymerase III (RPIII) from Plasmodium falciparum. The P. falciparum RPIII gene consists of 5 exons and 4 introns, is expressed in all of the asexual erythrocytic stages of the parasite as a 8.5-kb mRNA, and is present in a single copy on chromosome 13. The predicted 2339 amino acid residue RPIII subunit contained 5 regions that were conserved between different eukaryotic RPIII subunits, and 4 variable regions that separated the conserved regions. Three of the variable regions were greatly enlarged in comparison to the corresponding variable regions in other RPIII subunits. Variable region C' represented nearly one-third of the P. falciparum RPIII subunit (750 amino acid residues), included a unique repeated decapeptide sequence, and had some homology with yeast DNA topoisomerase II. Noteworthy amino acid sequences and structures were identified in both the conserved regions and in the enlarged variable regions, and their possible role(s) as domains that regulate RPIII enzyme activity is discussed. PMID:1656254

  8. Prokaryotic expression of the chicken xanthine oxidase (XOD) subunit and its localization in liver and kidney.

    Science.gov (United States)

    Lin, Huayuan; Chen, Yanjun; Huang, Qiqi; Guo, Xiaoquan; Liu, Ping; Liu, Weilian; Zhang, Caiying; Cao, Huabin; Hu, Guoliang

    2016-06-01

    Xanthine oxidase (XOD) is the members of the molybdenum hydroxylase flavoprotein family and it plays a vital role in the body's purine catabolism. In this study, we cloned the XOD 37kDa subunit protein by using RT-PCR and pMD-18-T clone vector based on the total RNA extracted from chicken liver. The cloning XOD subunit protein gene was ligated into the pET-32a to construct the recombinant plasmid pET-XOD. After the pET-XOD expression vector was transformed into host cells Rosetta (DE3), the recombinant XOD subunit proteins (54.8kDa) were successfully induced by isopropy1 β-d-thiogalactoside (IPTG). Rabbit antiserums were produced by using the purification of the recombinant XOD subunit protein as antigen. The titer of the antiserum was more than 1:102,400 determined by using ELISA. The result of Western blot demonstrated that the antiserum could specifically recognize the chicken liver XOD. Immunohistochemistry and immunofluorescence showed that the XOD mainly presented in the cytoplasm of chicken hepatocytes and proximal tubular epithelial cells. Our results indicated that the XOD subunit protein polyclonal antibody prepared by this method could be used for the further researches of the biological function of the XOD in the chicken. PMID:26949113

  9. Two Arabidopsis ADP-glucose pyrophosphorylase large subunits (APL1 and APL2) are catalytic.

    Science.gov (United States)

    Ventriglia, Tiziana; Kuhn, Misty L; Ruiz, Ma Teresa; Ribeiro-Pedro, Marina; Valverde, Federico; Ballicora, Miguel A; Preiss, Jack; Romero, José M

    2008-09-01

    ADP-glucose (Glc) pyrophosphorylase (ADP-Glc PPase) catalyzes the first committed step in starch biosynthesis. Higher plant ADP-Glc PPase is a heterotetramer (alpha(2)beta(2)) consisting of two small and two large subunits. There is increasing evidence that suggests that catalytic and regulatory properties of the enzyme from higher plants result from the synergy of both types of subunits. In Arabidopsis (Arabidopsis thaliana), two genes encode small subunits (APS1 and APS2) and four large subunits (APL1-APL4). Here, we show that in Arabidopsis, APL1 and APL2, besides their regulatory role, have catalytic activity. Heterotetramers formed by combinations of a noncatalytic APS1 and the four large subunits showed that APL1 and APL2 exhibited ADP-Glc PPase activity with distinctive sensitivities to the allosteric activator (3-phosphoglycerate). Mutation of the Glc-1-P binding site of Arabidopsis and potato (Solanum tuberosum) isoforms confirmed these observations. To determine the relevance of these activities in planta, a T-DNA mutant of APS1 (aps1) was characterized. aps1 is starchless, lacks ADP-Glc PPase activity, APS1 mRNA, and APS1 protein, and is late flowering in long days. Transgenic lines of the aps1 mutant, expressing an inactivated form of APS1, recovered the wild-type phenotype, indicating that APL1 and APL2 have catalytic activity and may contribute to ADP-Glc synthesis in planta. PMID:18614708

  10. Two Arabidopsis ADP-Glucose Pyrophosphorylase Large Subunits (APL1 and APL2) Are Catalytic1

    Science.gov (United States)

    Ventriglia, Tiziana; Kuhn, Misty L.; Ruiz, Ma Teresa; Ribeiro-Pedro, Marina; Valverde, Federico; Ballicora, Miguel A.; Preiss, Jack; Romero, José M.

    2008-01-01

    ADP-glucose (Glc) pyrophosphorylase (ADP-Glc PPase) catalyzes the first committed step in starch biosynthesis. Higher plant ADP-Glc PPase is a heterotetramer (α2β2) consisting of two small and two large subunits. There is increasing evidence that suggests that catalytic and regulatory properties of the enzyme from higher plants result from the synergy of both types of subunits. In Arabidopsis (Arabidopsis thaliana), two genes encode small subunits (APS1 and APS2) and four large subunits (APL1–APL4). Here, we show that in Arabidopsis, APL1 and APL2, besides their regulatory role, have catalytic activity. Heterotetramers formed by combinations of a noncatalytic APS1 and the four large subunits showed that APL1 and APL2 exhibited ADP-Glc PPase activity with distinctive sensitivities to the allosteric activator (3-phosphoglycerate). Mutation of the Glc-1-P binding site of Arabidopsis and potato (Solanum tuberosum) isoforms confirmed these observations. To determine the relevance of these activities in planta, a T-DNA mutant of APS1 (aps1) was characterized. aps1 is starchless, lacks ADP-Glc PPase activity, APS1 mRNA, and APS1 protein, and is late flowering in long days. Transgenic lines of the aps1 mutant, expressing an inactivated form of APS1, recovered the wild-type phenotype, indicating that APL1 and APL2 have catalytic activity and may contribute to ADP-Glc synthesis in planta. PMID:18614708

  11. Molecular Characterization of Subunit G of the Vacuolar ATPase in Pathogen Dermatophyte Trichophyton rubrum

    Directory of Open Access Journals (Sweden)

    S Rezaie

    2006-06-01

    Full Text Available Trichophyton rubrum is an anthropophilic fungus causing up to 90% of chronic cases of dermatophytosis. Several properties of this fungus have been investigated so far. However, a few studies were carried out in the field of molecular biology of this fungus. In the present study, we tried to identify the subunit G of its vacuolar ATPase (V-ATPase. Pairs of 21 nt primers were designed from highly conserved regions of the V-ATPase subunit G genes in other fungi. Mentioned primers were utilized in PCR using isolated genomic DNA template as well as cytoplasmic RNA of T.rubrum and the PCR and RT-PCR fragments were then sequenced. About 469 nucleotides were sequenced which encoded a polypeptide with 119 amino acids. Nucleotide sequence comparison in gene data banks (NCBI, NIH for both the DNA and its deduced amino acid sequence revealed significant homology with V-ATPase subunit G genes and proteins of other eukaryotic cells. The amino acid sequence of the encoded protein was about 84% identical to the sequence of V-ATPase subunit G from other fungi. In summary, we have cloned the first V-ATPase subunit G of dermatophytes and characterized it as a member of this gene family in other eukaryotic cells.

  12. Localization of the regulatory particle subunit Sem1 in the 26S proteasome

    International Nuclear Information System (INIS)

    Highlights: •26S proteasome subunit Sem1 was mapped using cryo-EM and cross-linking data. •C-terminal helix of Sem1 located near winged helix motif of Rpn7. •N-terminal part of Sem1 tethers Rpn7, Rpn3 and lid helical bundle. •Sem1 binds differently to PCI-domains of proteasome subunit Rpn7 and TREX-2 subunit Thp1. -- Abstract: The ubiquitin–proteasome system is responsible for regulated protein degradation in the cell with the 26S proteasome acting as its executive arm. The molecular architecture of this 2.5 MDa complex has been established recently, with the notable exception of the small acidic subunit Sem1. Here, we localize the C-terminal helix of Sem1 binding to the PCI domain of the subunit Rpn7 using cryo-electron microscopy single particle reconstruction of proteasomes purified from yeast cells with sem1 deletion. The approximate position of the N-terminal region of Sem1 bridging the cleft between Rpn7 and Rpn3 was inferred based on site-specific cross-linking data of the 26S proteasome. Our structural studies indicate that Sem1 can assume different conformations in different contexts, which supports the idea that Sem1 functions as a molecular glue stabilizing the Rpn3/Rpn7 heterodimer

  13. Localization of the regulatory particle subunit Sem1 in the 26S proteasome

    Energy Technology Data Exchange (ETDEWEB)

    Bohn, Stefan; Sakata, Eri; Beck, Florian; Pathare, Ganesh R.; Schnitger, Jérôme; Nágy, Istvan; Baumeister, Wolfgang, E-mail: baumeist@bichem.mpg.de; Förster, Friedrich, E-mail: foerster@bichem.mpg.de

    2013-05-31

    Highlights: •26S proteasome subunit Sem1 was mapped using cryo-EM and cross-linking data. •C-terminal helix of Sem1 located near winged helix motif of Rpn7. •N-terminal part of Sem1 tethers Rpn7, Rpn3 and lid helical bundle. •Sem1 binds differently to PCI-domains of proteasome subunit Rpn7 and TREX-2 subunit Thp1. -- Abstract: The ubiquitin–proteasome system is responsible for regulated protein degradation in the cell with the 26S proteasome acting as its executive arm. The molecular architecture of this 2.5 MDa complex has been established recently, with the notable exception of the small acidic subunit Sem1. Here, we localize the C-terminal helix of Sem1 binding to the PCI domain of the subunit Rpn7 using cryo-electron microscopy single particle reconstruction of proteasomes purified from yeast cells with sem1 deletion. The approximate position of the N-terminal region of Sem1 bridging the cleft between Rpn7 and Rpn3 was inferred based on site-specific cross-linking data of the 26S proteasome. Our structural studies indicate that Sem1 can assume different conformations in different contexts, which supports the idea that Sem1 functions as a molecular glue stabilizing the Rpn3/Rpn7 heterodimer.

  14. Investigation of the interaction between the large and small subunits of potato ADP-glucose pyrophosphorylase.

    Directory of Open Access Journals (Sweden)

    Ibrahim Baris

    2009-10-01

    Full Text Available ADP-glucose pyrophosphorylase (AGPase, a key allosteric enzyme involved in higher plant starch biosynthesis, is composed of pairs of large (LS and small subunits (SS. Current evidence indicates that the two subunit types play distinct roles in enzyme function. Recently the heterotetrameric structure of potato AGPase has been modeled. In the current study, we have applied the molecular mechanics generalized born surface area (MM-GBSA method and identified critical amino acids of the potato AGPase LS and SS subunits that interact with each other during the native heterotetrameric structure formation. We have further shown the role of the LS amino acids in subunit-subunit interaction by yeast two-hybrid, bacterial complementation assay and native gel. Comparison of the computational results with the experiments has indicated that the backbone energy contribution (rather than the side chain energies of the interface residues is more important in identifying critical residues. We have found that lateral interaction of the LS-SS is much stronger than the longitudinal one, and it is mainly mediated by hydrophobic interactions. This study will not only enhance our understanding of the interaction between the SS and the LS of AGPase, but will also enable us to engineer proteins to obtain better assembled variants of AGPase which can be used for the improvement of plant yield.

  15. Goniometer-based femtosecond X-ray diffraction of mutant 30S ribosomal subunit crystals.

    Science.gov (United States)

    Dao, E Han; Sierra, Raymond G; Laksmono, Hartawan; Lemke, Henrik T; Alonso-Mori, Roberto; Coey, Aaron; Larsen, Kevin; Baxter, Elizabeth L; Cohen, Aina E; Soltis, S Michael; DeMirci, Hasan

    2015-07-01

    In this work, we collected radiation-damage-free data from a set of cryo-cooled crystals for a novel 30S ribosomal subunit mutant using goniometer-based femtosecond crystallography. Crystal quality assessment for these samples was conducted at the X-ray Pump Probe end-station of the Linac Coherent Light Source (LCLS) using recently introduced goniometer-based instrumentation. These 30S subunit crystals were genetically engineered to omit a 26-residue protein, Thx, which is present in the wild-type Thermus thermophilus 30S ribosomal subunit. We are primarily interested in elucidating the contribution of this ribosomal protein to the overall 30S subunit structure. To assess the viability of this study, femtosecond X-ray diffraction patterns from these crystals were recorded at the LCLS during a protein crystal screening beam time. During our data collection, we successfully observed diffraction from these difficult-to-grow 30S ribosomal subunit crystals. Most of our crystals were found to diffract to low resolution, while one crystal diffracted to 3.2 Å resolution. These data suggest the feasibility of pursuing high-resolution data collection as well as the need to improve sample preparation and handling in order to collect a complete radiation-damage-free data set using an X-ray Free Electron Laser. PMID:26798805

  16. Goniometer-based femtosecond X-ray diffraction of mutant 30S ribosomal subunit crystals

    Directory of Open Access Journals (Sweden)

    E. Han Dao

    2015-07-01

    Full Text Available In this work, we collected radiation-damage-free data from a set of cryo-cooled crystals for a novel 30S ribosomal subunit mutant using goniometer-based femtosecond crystallography. Crystal quality assessment for these samples was conducted at the X-ray Pump Probe end-station of the Linac Coherent Light Source (LCLS using recently introduced goniometer-based instrumentation. These 30S subunit crystals were genetically engineered to omit a 26-residue protein, Thx, which is present in the wild-type Thermus thermophilus 30S ribosomal subunit. We are primarily interested in elucidating the contribution of this ribosomal protein to the overall 30S subunit structure. To assess the viability of this study, femtosecond X-ray diffraction patterns from these crystals were recorded at the LCLS during a protein crystal screening beam time. During our data collection, we successfully observed diffraction from these difficult-to-grow 30S ribosomal subunit crystals. Most of our crystals were found to diffract to low resolution, while one crystal diffracted to 3.2 Å resolution. These data suggest the feasibility of pursuing high-resolution data collection as well as the need to improve sample preparation and handling in order to collect a complete radiation-damage-free data set using an X-ray Free Electron Laser.

  17. Chromosomal localization of genes encoding guanine nucleotide-binding protein subunits in mouse and human

    Energy Technology Data Exchange (ETDEWEB)

    Blatt, C.; Eversole-Cire, P.; Cohn, V.H.; Zollman, S.; Fournier, R.E.K.; Mohandas, L.T.; Nesbitt, M.; Lugo, T.; Jones, D.T.; Reed, R.R.; Weiner, L.P.; Sparkes, R.S.; Simon, M.I. (Weizmann Institute, Rehovoth (Israel))

    1988-10-01

    A variety of genes have been identified that specify the synthesis of the components of guanine nucleotide-binding proteins (G proteins). Eight different guanine nucleotide-binding {alpha}-subunit proteins, two different {beta} subunits, and one {gamma} subunit have been described. Hybridization of cDNA clones with DNA from human-mouse somatic cell hybrids was used to assign many of these genes to human chromosomes. The retinal-specific transducin subunit genes GNAT1 and GNAT2 were on chromosomes 3 and 1; GNAI1, GNAI2, and GNAI3 were assigned to chromosomes 7, 3, and 1, respectively; GNAZ and GNAS were found on chromosomes 22 and 20. The {beta} subunits were also assigned-GNB1 to chromosome 1 and GNB2 to chromosome 7. Restriction fragment length polymorphisms were used to map the homologues of some of these genes in the mouse. GNAT1 and GNAI2 were found to map adjacent to each other on mouse chromosome 9 and GNAT2 was mapped on chromosome 17. The mouse GNB1 gene was assigned to chromosome 19. These mapping assignments will be useful in defining the extend of the G{alpha} gene family and may help in attempts to correlate specific genetic diseases and with genes corresponding to G proteins.

  18. Chromosomal localization of genes encoding guanine nucleotide-binding protein subunits in mouse and human.

    Science.gov (United States)

    Blatt, C; Eversole-Cire, P; Cohn, V H; Zollman, S; Fournier, R E; Mohandas, L T; Nesbitt, M; Lugo, T; Jones, D T; Reed, R R

    1988-10-01

    A variety of genes have been identified that specify the synthesis of the components of guanine nucleotide-binding proteins (G proteins). Eight different guanine nucleotide-binding alpha-subunit proteins, two different beta subunits, and one gamma subunit have been described. Hybridization of cDNA clones with DNA from human-mouse somatic cell hybrids was used to assign many of these genes to human chromosomes. The retinal-specific transducin subunit genes GNAT1 and GNAT2 were on chromosomes 3 and 1; GNAI1, GNAI2, and GNAI3 were assigned to chromosomes 7, 3, and 1, respectively; GNAZ and GNAS were found on chromosomes 22 and 20. The beta subunits were also assigned--GNB1 to chromosome 1 and GNB2 to chromosome 7. Restriction fragment length polymorphisms were used to map the homologues of some of these genes in the mouse. GNAT1 and GNAI2 were found to map adjacent to each other on mouse chromosome 9 and GNAT2 was mapped on chromosome 17. The mouse GNB1 gene was assigned to chromosome 19. These mapping assignments will be useful in defining the extent of the G alpha gene family and may help in attempts to correlate specific genetic diseases with genes corresponding to G proteins. PMID:2902634

  19. Subunit composition of hinokiresinol synthase controls enantiomeric selectivity in hinokiresinol formation.

    Science.gov (United States)

    Yamamura, Masaomi; Suzuki, Shiro; Hattori, Takefumi; Umezawa, Toshiaki

    2010-03-01

    Asparagus officinalis hinokiresinol synthase (HRS) is composed of two subunits, HRSalpha and HRSbeta. Individually, each subunit forms (E)-hinokiresinol (EHR) from 4-coumaryl 4-coumarate, whereas a mixture of both subunits forms (Z)-hinokiresinol (ZHR) from the same substrate. In this study, we analyzed the enantiomeric compositions of ZHR and EHR formed after incubation of 4-coumaryl 4-coumarate with recombinant subunit proteins, recHRSalpha and/or recHRSbeta, and with naturally occurring A. officinalis ZHR. The enantiomeric composition of ZHR formed by the mixture of recHRSalpha and recHRSbeta was (+)-100% enantiomer excess (e.e.), identical to that of A. officinalis ZHR. In contrast, the enantiomeric compositions of EHR formed by recHRSalpha and recHRSbeta, individually, were (-)-20.6 and (-)-9.0% e.e., respectively. These results clearly demonstrate that the subunit composition of A. officinalis HRS controls not only cis/trans isomerism but also enantioselectivity in hinokiresinol formation. PMID:20165801

  20. [Eutopic and ectopic production of glycoprotein hormones alpha and beta subunits].

    Science.gov (United States)

    Bidart, J M; Baudin, E; Troalen, F; Bellet, D; Schlumberger, M

    1997-01-01

    Human chorionic gonadotropin (hCG) is a glycoprotein composed of two subunits, alpha and beta, linked together by a covalent bond. Ectopic production of hCG has been described in various histological types of cancer. Actually, these malignant tumors predominantly secrete the free beta subunit (hCG beta) and not hCG. Production of free hCG beta is especially found in patients with bladder, pancreas, uterine and lung tumors. In patients with neuroendocrine tumors, serum levels of free hCG beta are higher in gastrointestinal-pancreatic and lung tumors. The significance of ectopic production of hCG beta--epiphenomena or intrinsic biological role--remains unknown. Several reports on the similar structure of hCG beta and certain growth factors suggest that free hCG beta could have an effect on cell proliferation. Increased serum levels of the free alpha subunit are found mainly in patients with neuroendocrine tumors localized in the gut or lung. Serum levels may also be raised in patients with a pituitary tumor, but such production is often associated with a rise in other pituitary hormones. The free alpha subunit plays a role in embryon development and would stimulate production of prolactin by decidual cells. The free alpha subunit may also play a role in tumor growth. PMID:9239230

  1. Molecular basis of inherited calcium Channelopathies: role of mutations in pore-forming subunits

    Institute of Scientific and Technical Information of China (English)

    Lynn MCKEOWN; Philip ROBINSON; Owen T JONES

    2006-01-01

    The pore-forming alpha subunits of voltage-gated calcium channels contain the essential biophysical machinery that underlies calcium influx in response to cell depolarization.In combination with requisite auxiliary subunits,these pore subunits form calcium channel complexes that are pivotal to the physiology and pharmacology of diverse cells ranging from sperm to neurons.Not surprisingly,mutations in the pore subunits generate diverse pathologies,termed channelopathies,that range from failures in excitation-contraction coupling to night blindness.Over the last decade, major insights into the mechanisms of pathogenesis have been derived from animals showing spontaneous or induced mutations.In parallel,there has been considerable growth in our understanding of the workings of voltage-gated ion channels from a structure-function,regulation and cell biology perspective.Here we document our current understanding of the mutations underlying channelopathies involving the voltage-gated calcium channel alpha subunits in humans and other species.

  2. Morphological variation of individual Escherichia coli 50S ribosomal subunits in situ, as revealed by cryo-electron tomography

    International Nuclear Information System (INIS)

    Electron tomography (ET) has been used to reconstruct in situ individual 50S ribosomal subunits in Escherichia coli rifampicin-treated cells. Rifampicin inhibits transcription initiation. As a result, rapid degradation of preformed mRNA and dissociation of 70S ribosomes give accumulation of free subunits. In the 50S subunit, the L1 stalk, the L7/L12 stalk, the central protuberance (CP), and the peptidyl transferase center (PTC) cleft are the most dynamic and flexible parts in the reconstructed structures with clear movements indicated. Different locations of the tunnel in the central cross-sections through the in situ 50S subunits indicate the flexible nature of the pathway inside the large ribosomal subunit. In addition, gross morphological heterogeneity was observed in the reconstructions. Our results demonstrate a considerable structural variability among individual 50S subunits in the intracellular environment

  3. Characterization of the alpha and beta subunits of casein kinase 2 by far-UV CD spectroscopy

    DEFF Research Database (Denmark)

    Issinger, O G; Brockel, C; Boldyreff, B; Pelton, J T

    1992-01-01

    Although Chou-Fasman calculations of the secondary structure of recombinant casein kinase 2 subunits alpha and beta suggest they have a similar overall conformation, circular dichroism (CD) studies show that substantial differences in the conformation of the two subunits exist. In addition......, no changes in the far-UV CD spectrum of the alpha subunit are observed in the presence of casein or the synthetic decapeptide substrate RRRDDDSDDD. Furthermore, the alpha-helical structure of the alpha subunit (but not the beta subunit) can be increased in the presence of stoichiometric amounts of...... heparin, presumably by its binding to the polylysine stretch at amino acid positions 74-77. Heat denaturation experiments (25-90 degrees C) support the notion that heparin may provide a local protective function. A similar but much larger effect was also observed in the presence of the beta subunit only...

  4. Multi-agent Response Simulation of Industrial Loads for Ancillary Services%工业负荷提供辅助服务的多智能体响应模拟

    Institute of Scientific and Technical Information of China (English)

    姚明涛; 胡兆光; 张宁; 段炜; 张健

    2014-01-01

    ABSTRACT:The characteristics of demand side resources, such as fast response and low cost, are very helpful to improve wind power penetration when they are utilized to provide ancillary services for the power system. Typically, industrial demand response resources have the advantages of large capacity, load stability and are easy to manage when they are compared with commerce and inhabitant users. As a result, industrial demand response resources are very suitable to deal with large-scale wind power integration. In order to have an in-depth study on the response mechanism of industrial loads to provide ancillary services, this paper chosen electrolytic aluminum and irrigation pumping station as two typical industrial power users and analyzed the ancillary services type which could be provided. Then, a multi-agent response modeling containing these two kinds of industrial loads and the grid was built based on multi-agent technology. The goal, structure and behavior strategies of each agent were explained in the paper. In the process of simulation, the grid companies could adjust the ancillary services price according to the response of industrial power consumers. The results show that the pricing strategy of ancillary services in this model can fully exploit the response potential of all types of industrial power users to provide ancillary services while satisfying their interests.%挖掘响应迅速且成本较低的需求侧资源为电力系统提供辅助服务,对促进风电消纳具有积极意义。工业需求响应资源与商业、居民等用户相比具有容量大、负荷稳定、易于管理等优势,在应对大规模风电接入等方面具有更明显的优势。为深入研究工业用户提供辅助服务的响应机理,在分析电解铝、灌溉泵站2类典型工业负荷提供辅助服务类型的基础上,基于多智能体技术,构建了包含电网及以上2类工业负荷的多智能体系统,阐述各类智能体的目标

  5. Deletion of the GABAA α2-subunit does not alter self dministration of cocaine or reinstatement of cocaine seeking

    OpenAIRE

    Dixon, C. I.; Halbout, B.; King, S.L.; Stephens, D. N.

    2014-01-01

    Rationale GABAA receptors containing α2-subunits are highly represented in brain areas that are involved in motivation and reward, and have been associated with addiction to several drugs, including cocaine. We have shown previously that a deletion of the α2-subunit results in an absence of sensitisation to cocaine. Objective We investigated the reinforcing properties of cocaine in GABAA α2-subunit knockout (KO) mice using an intravenous self-administration procedure. Methods ...

  6. Cop9/signalosome subunits and Pcu4 regulate ribonucleotide reductase by both checkpoint-dependent and -independent mechanisms

    OpenAIRE

    Liu, Cong; Powell, Kelly A.; Mundt, Kirsten; Wu, LeJung; Carr, Antony M.; Caspari, Thomas

    2003-01-01

    The signalosome is implicated in regulating cullin-dependent ubiquitin ligases. We find that two signalosome subunits, Csn1 and Csn2, are required to regulate ribonucleotide reductase (RNR) through the degradation of a small protein, Spd1, that acts to anchor the small RNR subunit in the nucleus. Spd1 destruction correlates with the nuclear export of the small RNR subunit, which, in turn, correlates with a requirement for RNR in replication and repair. Spd1 degradation is promoted by two sepa...

  7. Evolution of Respiratory Complex I: “SUPERNUMERARY” SUBUNITS ARE PRESENT IN THE α-PROTEOBACTERIAL ENZYME*

    OpenAIRE

    Yip, Chui-ying; Harbour, Michael E; Jayawardena, Kamburapola; Fearnley, Ian M.; Sazanov, Leonid A.

    2010-01-01

    Modern α-proteobacteria are thought to be closely related to the ancient symbiont of eukaryotes, an ancestor of mitochondria. Respiratory complex I from α-proteobacteria and mitochondria is well conserved at the level of the 14 “core” subunits, consistent with that notion. Mitochondrial complex I contains the core subunits, present in all species, and up to 31 “supernumerary” subunits, generally thought to have originated only within eukaryotic lineages. However, the full protein composition ...

  8. Diversity in genomic organisation, developmental regulation and distribution of the murine PR72/B" subunits of protein phosphatase 2A

    OpenAIRE

    Janssens Veerle; Goris Jozef; Louis Justin V; Zwaenepoel Karen

    2008-01-01

    Abstract Background Protein phosphatase 2A (PP2A) is a serine/threonine-specific phosphatase displaying vital functions in growth and development through its role in various signalling pathways. PP2A holoenzymes comprise a core dimer composed of a catalytic C and a structural A subunit, which can associate with a variable B-type subunit. The importance of the B-type subunits for PP2A regulation cannot be overestimated as they determine holoenzyme localisation, activity and substrate specifici...

  9. Sequence analysis of dolphin ferritin H and L subunits and possible iron-dependent translational control of dolphin ferritin gene

    OpenAIRE

    Sasaki Yukako; Takai Shinji; Watanabe Kiyotaka; Takaesu Azusa; Orino Koichi

    2008-01-01

    Abstract Background Iron-storage protein, ferritin plays a central role in iron metabolism. Ferritin has dual function to store iron and segregate iron for protection of iron-catalyzed reactive oxygen species. Tissue ferritin is composed of two kinds of subunits (H: heavy chain or heart-type subunit; L: light chain or liver-type subunit). Ferritin gene expression is controlled at translational level in iron-dependent manner or at transcriptional level in iron-independent manner. However, sequ...

  10. Characterization of Rabbit Polyclonal Sera against Recombinant Shiga Toxin and its Subunits for Detection of Stx-Producing E. coli

    OpenAIRE

    Mana Oloomi; Saeid Bouzari

    2011-01-01

    Shiga toxin (Stx) is the principal virulence factor of Shigatoxigenic Escherichia coli (STEC), a food-born pathogen associated disease with uncomplicated diarrhea or the hemolytic-uremic syndrome. In this study, rabbit polyclonal anti recombinant A, B subunits of Shiga toxin and holotoxin antisera were raised and employed for immunological purpose. By immunoblotting, these antisera recognized respective subunit and the holotoxin antiserum recognized both subunits, equally. The raised antisera...

  11. In vitro assembly of homopolymer and copolymer filaments from intermediate filament subunits of muscle and fibroblastic cells.

    OpenAIRE

    Steinert, P M; Idler, W W; Cabral, F; Gottesman, M M; Goldman, R D

    1981-01-01

    This paper presents evidence that the intermediate filament (IF) subunits of muscle cells (skeletin or desmin) and fibroblastic cells (decamin or vimentin) separately form homopolymer IF in vitro and, when mixed, prefer to form copolymer IF in vitro. Because they coexist in cells, they may also form copolymers in vivo. The IFs of baby hamster kidney fibroblasts (BHK-21) consist of a major subunit, decamin, and two minor subunits which, on the basis of two-dimensional gel and peptide mapping c...

  12. Characterization of Rabbit Polyclonal Sera Against Recombinant Shiga Toxin and its Subunits for Detection of Stx-Producing E. Coli

    OpenAIRE

    Mana Oloomi; Saeid Bouzari

    2011-01-01

    Shiga toxin (Stx) is the principal virulence factor of Shigatoxigenic Escherichia coli (STEC), a food-born pathogen associated disease with uncomplicated diarrhea or the hemolytic-uremic syndrome. In this study, rabbit polyclonal anti recombinant A, B subunits of Shiga toxin and holotoxin antisera were raised and employed for immunological purpose. By immunoblotting, these antisera recognized respective subunit and the holotoxin antiserum recognized both subunits, equally. The raised antisera...

  13. Protein kinase CK2: evidence for a protein kinase CK2beta subunit fraction, devoid of the catalytic CK2alpha subunit, in mouse brain and testicles

    DEFF Research Database (Denmark)

    Guerra, B; Siemer, S; Boldyreff, B;

    1999-01-01

    The highest CK2 activity was found in mouse testicles and brain, followed by spleen, liver, lung, kidney and heart. The activity values were directly correlated with the protein expression level of the CK2 subunits alpha (catalytic) and beta (regulatory). The alpha' subunit was only detected in...... found for testicles and brain. The amount of CK2beta protein in brain in comparison to the other organs (except testicles) was estimated to be ca. 2-3-fold higher whereas the ratio of CK2beta between testicles and brain was estimated to be 3-4-fold. Results from the immunoprecipitation experiments...... support the notion for the existence of free CK2beta population and/or CK2beta in complex with other protein(s) present in brain and testicles. In all other mouse organs investigated, i.e. heart, lung, liver, kidney and spleen, no comparable amount of free CK2beta was observed. This is the first...

  14. A-Raf kinase is a new interacting partner of protein kinase CK2 beta subunit

    DEFF Research Database (Denmark)

    Boldyreff, B; Issinger, O G

    1997-01-01

    In a search for protein kinase CK2 beta subunit binding proteins using the two-hybrid system, more than 1000 positive clones were isolated. Beside clones for the alpha' and beta subunit of CK2, there were clones coding for a so far unknown protein, whose partial cDNA sequence was already deposited...... in the EMBL database under the accession numbers R08806 and Z17360, for the ribosomal protein L5 and for A-Raf kinase. All isolated clones except the one for CK2 beta showed no interaction with the catalytic alpha subunit of CK2. A-Raf kinase is a new interesting partner of CK2 beta. The isolated A...

  15. Model for growth hormone receptor activation based on subunit rotation within a receptor dimer

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Richard J.; Adams, Julian J.; Pelekanos, Rebecca A.; Wan, Yu; McKinstry, William J.; Palethorpe, Kathryn; Seeber, Ruth M.; Monks, Thea A.; Eidne, Karin A.; Parker, Michael W.; Waters, Michael J. (UWA); (St. Vincent); (Queensland)

    2010-07-13

    Growth hormone is believed to activate the growth hormone receptor (GHR) by dimerizing two identical receptor subunits, leading to activation of JAK2 kinase associated with the cytoplasmic domain. However, we have reported previously that dimerization alone is insufficient to activate full-length GHR. By comparing the crystal structure of the liganded and unliganded human GHR extracellular domain, we show here that there is no substantial change in its conformation on ligand binding. However, the receptor can be activated by rotation without ligand by inserting a defined number of alanine residues within the transmembrane domain. Fluorescence resonance energy transfer (FRET), bioluminescence resonance energy transfer (BRET) and coimmunoprecipitation studies suggest that receptor subunits undergo specific transmembrane interactions independent of hormone binding. We propose an activation mechanism involving a relative rotation of subunits within a dimeric receptor as a result of asymmetric placement of the receptor-binding sites on the ligand.

  16. A family of acetylcholine-gated chloride channel subunits in Caenorhabditis elegans.

    Science.gov (United States)

    Putrenko, Igor; Zakikhani, Mahvash; Dent, Joseph A

    2005-02-25

    The genome of the nematode Caenorhabditis elegans encodes a surprisingly large and diverse superfamily of genes encoding Cys loop ligand-gated ion channels. Here we report the first cloning, expression, and pharmacological characterization of members of a family of anion-selective acetylcholine receptor subunits. Two subunits, ACC-1 and ACC-2, form homomeric channels for which acetylcholine and arecoline, but not nicotine, are efficient agonists. These channels are blocked by d-tubocurarine but not by alpha-bungarotoxin. We provide evidence that two additional subunits, ACC-3 and ACC-4, interact with ACC-1 and ACC-2. The acetylcholine-binding domain of these channels appears to have diverged substantially from the acetylcholine-binding domain of nicotinic receptors. PMID:15579462

  17. Cox26 is a novel stoichiometric subunit of the yeast cytochrome c oxidase.

    Science.gov (United States)

    Levchenko, Maria; Wuttke, Jan-Moritz; Römpler, Katharina; Schmidt, Bernhard; Neifer, Klaus; Juris, Lisa; Wissel, Mirjam; Rehling, Peter; Deckers, Markus

    2016-07-01

    The cytochrome c oxidase (COX) is the terminal enzyme of the respiratory chain. The complex accepts electrons from cytochrome c and passes them onto molecular oxygen. This process contributes to energy capture in the form of a membrane potential across the inner membrane. The enzyme complex assembles in a stepwise process from the three mitochondria-encoded core subunits Cox1, Cox2 and Cox3, which associate with nuclear-encoded subunits and cofactors. In the yeast Saccharomyces cerevisiae, the cytochrome c oxidase associates with the bc1-complex into supercomplexes, allowing efficient energy transduction. Here we report on Cox26 as a protein found in respiratory chain supercomplexes containing cytochrome c oxidase. Our analyses reveal Cox26 as a novel stoichiometric structural subunit of the cytochrome c oxidase. A loss of Cox26 affects cytochrome c oxidase activity and respirasome organization. PMID:27083394

  18. Kir3 channel ontogeny - the role of Gβγ subunits in channel assembly and trafficking.

    Directory of Open Access Journals (Sweden)

    Ashley M Jacobi

    2014-04-01

    Full Text Available The role of Gβγ subunits in Kir3 channel gating is well characterized. Here, we have studied the role of Gβγ dimers during their initial contact with Kir3 channels, prior to their insertion into the plasma membrane. We show that distinct Gβγ subunits play an important role in orchestrating and fine-tuning parts of the Kir3 channel life cycle. Gβ1γ2, apart from its role in channel opening that it shares with other Gβγ subunit combinations, may play a unique role in protecting maturing channels from degradation as they transit to the cell surface. Taken together, our data suggest that Gβ1γ2 prolongs the lifetime of the Kir3.1/Kir3.2 heterotetramer, although further studies would be required to shed more light on these early Gβγ effects on Kir3 maturation and trafficking.

  19. Cloning, Expression and Purification of Subunit H of Vacuolar H+-ATPase from Mythimna separata Walker (Lepidoptera: Noctuidae

    Directory of Open Access Journals (Sweden)

    Lina Lu

    2014-09-01

    Full Text Available The vacuolar (H+-ATPase (V-ATPase of insect, which is composed of membrane-bound V0 complex and peripheral V1 complex, participates in lots of important physiological process. Subunit H, as a subunit of V1 complex, plays a vital role in bridging the communication between V1 and V0 complexes and interaction with other proteins. Yeast subunit H has been successfully crystallized through expression in E. coli, but little is known about the structure of insect subunit H. In this study, we cloned, expressed and purified the subunit H from midgut of Mythimna separata Walker. Through RACE (rapidly amplification of cDNA ends technique, we got 1807 bp full length of subunit H, and to keep the nature structure of subunit H, we constructed Baculovirus expression vector with His-tag in the C-terminal and expressed the recombinant protein in insect sf9 cells, thereafter, purified the recombinant protein by Ni-NTA columns. Results of SDS-PAGE, western blotting and mass spectrometry showed that the recombinant protein was successfully expressed. The method of expressing and purifying M. separata subunit H will provide a foundation for obtaining the crystal of subunit H and further study of the design of novel insecticides based on its structure and function.

  20. Cloning, Expression and Purification of Subunit H of Vacuolar H+-ATPase from Mythimna separata Walker (Lepidoptera: Noctuidae)

    OpenAIRE

    Lina Lu; Zhijun Qi; Wenjun Wu

    2014-01-01

    The vacuolar (H+)-ATPase (V-ATPase) of insect, which is composed of membrane-bound V0 complex and peripheral V1 complex, participates in lots of important physiological process. Subunit H, as a subunit of V1 complex, plays a vital role in bridging the communication between V1 and V0 complexes and interaction with other proteins. Yeast subunit H has been successfully crystallized through expression in E. coli, but little is known about the structure of insect subunit H. In this study, we clone...