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Sample records for periplasmic c-5 mannuronan

  1. Structural and mutational characterization of the catalytic A-module of the mannuronan C-5-epimerase AlgE4 from Azotobacter vinelandii

    NARCIS (Netherlands)

    Rozeboom, Henriette J.; Bjerkan, Tonje M.; Kalk, Kor H.; Ertesvag, Helga; Holtan, Synnove; Aachmann, Finn L.; Valla, Svein; Dijkstra, Bauke W.; Ertesvåg, Helga; Holtan, Synnøve

    2008-01-01

    Alginate is a family of linear copolymers of (1 -> 4)-linked beta-D-mannuronic acid and its C-5 epimer alpha-L-guluronic acid. The polymer is first produced as polymannuronic acid and the guluronic acid residues are then introduced at the polymer level by mannuronan C-5-epimerases. The structure of

  2. Cloning and Expression of Three New Azotobacter vinelandii Genes Closely Related to a Previously Described Gene Family Encoding Mannuronan C-5-Epimerases

    OpenAIRE

    Svanem, Britt Iren Glærum; Skjåk-Bræk, Gudmund; Ertesvåg, Helga; Valla, Svein

    1999-01-01

    The cloning and expression of a family of five modular-type mannuronan C-5-epimerase genes from Azotobacter vinelandii (algE1 to -5) has previously been reported. The corresponding proteins catalyze the Ca2+-dependent polymer-level epimerization of β-d-mannuronic acid to α-l-guluronic acid (G) in the commercially important polysaccharide alginate. Here we report the identification of three additional structurally similar genes, designated algE6, algE7, and algY. All three genes were sequenced...

  3. The gram-negative bacterial periplasm: Size matters.

    Directory of Open Access Journals (Sweden)

    Samuel I Miller

    2018-01-01

    Full Text Available Gram-negative bacteria are surrounded by two membrane bilayers separated by a space termed the periplasm. The periplasm is a multipurpose compartment separate from the cytoplasm whose distinct reducing environment allows more efficient and diverse mechanisms of protein oxidation, folding, and quality control. The periplasm also contains structural elements and important environmental sensing modules, and it allows complex nanomachines to span the cell envelope. Recent work indicates that the size or intermembrane distance of the periplasm is controlled by periplasmic lipoproteins that anchor the outer membrane to the periplasmic peptidoglycan polymer. This periplasm intermembrane distance is critical for sensing outer membrane damage and dictates length of the flagellar periplasmic rotor, which controls motility. These exciting results resolve longstanding debates about whether the periplasmic distance has a biological function and raise the possibility that the mechanisms for maintenance of periplasmic size could be exploited for antibiotic development.

  4. Effect of promoter strength and signal sequence on the periplasmic ...

    African Journals Online (AJOL)

    Two plasmids, pFLAG-ATS and pET 26b(+), were studied for the periplasmic expression of recombinant human interferon-2b (IFN-2b) in Escherichia coli. The pFLAG-ATS contains ompA signal sequence and tac promoter while pET 26b(+) contains pelB signal sequence and T7lac promoter. It was observed that periplasmic ...

  5. Periplasmic quality control in biogenesis of outer membrane proteins.

    Science.gov (United States)

    Lyu, Zhi Xin; Zhao, Xin Sheng

    2015-04-01

    The β-barrel outer membrane proteins (OMPs) are integral membrane proteins that reside in the outer membrane of Gram-negative bacteria and perform a diverse range of biological functions. Synthesized in the cytoplasm, OMPs must be transported across the inner membrane and through the periplasmic space before they are assembled in the outer membrane. In Escherichia coli, Skp, SurA and DegP are the most prominent factors identified to guide OMPs across the periplasm and to play the role of quality control. Although extensive genetic and biochemical analyses have revealed many basic functions of these periplasmic proteins, the mechanism of their collaboration in assisting the folding and insertion of OMPs is much less understood. Recently, biophysical approaches have shed light on the identification of the intricate network. In the present review, we summarize recent advances in the characterization of these key factors, with a special emphasis on the multifunctional protein DegP. In addition, we present our proposed model on the periplasmic quality control in biogenesis of OMPs.

  6. Osmoregulated periplasmic glucans synthesis gene family of Shigella flexneri

    Science.gov (United States)

    Osmoregulated periplasmic glucans (OPGs) of foodborne enteropathogen Shigella flexneri were characterized. OPGs were composed of 100 percent glucose with 2-linked glucose as the most abundant residue with terminal glucose, 2-linked and 2,6-linked glucose also present in high quantities. Most dominan...

  7. C5 capsule operation modes analysis

    International Nuclear Information System (INIS)

    Negut, Gh.; Ancuta, Mirela; Stefan, Violeta

    2008-01-01

    This paper is part of the Nuclear Research Institute Program 13 dedicated to 'TRIGA Research Reactor performance enhancing' and its objective is improving the engineering of the structural materials irradiation. The paper raises the knowledge level on C5 capsule irradiation modes and utilizes previous results in order to increase C5 performances. In the paper the irradiation modes to test zirconium yttrium sample are assessed. These tests are proposed by AECL. There are presented the C5 initial conditions and models. Also. there are presented the thermal hydraulic conditions during normal and accidental operation. The results will be used in the C5 safety report. (authors)

  8. Multithreading in C# 5.0 cookbook

    CERN Document Server

    Agafonov, Eugene

    2013-01-01

    Cookbook.Multithreading in C# 5.0 Cookbook is written for existing C# developers who want a complete, professional, and authoritative guide to multithreading. You don't need any experience with multithreaded programming to use this book.

  9. On the pull: periplasmic trapping of sugars before transport.

    Science.gov (United States)

    Thomas, Gavin H

    2017-06-01

    Bacteria have evolved many routes for taking up nutrients, demonstrating great versatility in the types and mechanism of uptake used in different physiological conditions. The discovery of a single transporter in the bacterium Advenella mimigardefordensis for the uptake of five different sugars, including L-glucose and D-xylose, is described in this issue (Meinert et al., ), providing yet another example of the surprising adaptability of bacterial transport strategies. The transporter identified is a tripartite ATP-independent (TRAP) transporter, not previously associated with sugar transport, and in fact does not transport the sugars directly at all, rather requiring them to be converted in the periplasm to their respective sugar acid forms before transport through what appears to be a novel general sugar acid transporter. In this commentary, I describe how this process is consistent with the known mechanisms of TRAP transporters and consider how the role of sugar oxidation, or oxidative fermentation, operates with multiple hexose and pentose sugars. Finally I suggest that the periplasmic conversion of nutrients acquired across the outer membrane, before transport across the inner membrane, could have potentially useful biological functions in Gram negative bacteria. © 2017 John Wiley & Sons Ltd.

  10. 76 FR 69636 - Amides, C5

    Science.gov (United States)

    2011-11-09

    ... in guinea pigs showed that amides, C 5 - C 9 , N-[3-(dimethylamino) propyl] was not a skin sensitizer.... Potentially affected entities may include, but are not limited to: Crop production (NAICS code 111). Animal production (NAICS code 112). Food manufacturing (NAICS code 311). Pesticide manufacturing (NAICS code 32532...

  11. Metabolism of periplasmic membrane-derived oligosaccharides by the predatory bacterium Bdellovibrio bacteriovorus 109J

    International Nuclear Information System (INIS)

    Ruby, E.G.; McCabe, J.B.

    1988-01-01

    Membrane-derived oligosaccharides (MDO), a class of osmotically active carbohydrates, are the major organic solutes present in the periplasm of Escherichia coli and many other gram-negative bacteria when cells are grown in a medium of low osmolarity. Analyses of growing cells of Bdellovibrio bacteriovorus, a gram-negative predator of other bacteria, have confirmed that they also synthesize a characteristic MDO-like class of oligosaccharides. The natural growth environment of bdellovibrios is the periplasm of other gram-negative bacteria. Because of this location, prey cell MDO constitute a potential source of organic nutrients for growing bdellovibrios. Using cells of E. coli whose MDO were 3 H labeled, we examined the extent to which B. bacteriovorus 109J metabolizes these prey cell components. Interestingly, there was neither significant degradation nor incorporation of prey cell MDO by bdellovibrios during the course of their intracellular growth. In fact, bdellovibrios had little capability either to degrade extracellular MDO that was made available to them or to transport glucose, the major monomeric constituent of prey cell MDO. Instead, periplasmic MDO were irreversibly lost to the extracellular environment during the period of bdellovibrio attack and penetration. Thus, although prey cell periplasmic proteins are retained, other important periplasmic components are released early in the bdellovibrio growth cycle. The loss of these MDO may aid in the destabilization of the prey cell plasma membrane, increasing the availability of cytoplasmic constituents to the periplasmic bdellovibrio

  12. SL(C) 5 migration at CERN

    International Nuclear Information System (INIS)

    Schwickerath, Ulrich; Silva, Ricardo

    2010-01-01

    Most LCG sites are currently running on SL(C)4. However, this operating system is already rather old, and it is becoming difficult to get the required hardware drivers, to get the best out of recent hardware. A possible way out is the migration to SL(C)5 based systems where possible, in combination with virtualization methods. The former is typically possible for nodes where the software to run the services is available and tested, while the latter offers a possibility to make use of the new hardware platforms whilst maintaining operating system compatibility. Since autumn 2008, CERN has offered public interactive and batch worker nodes for evaluation to the experiments. For the Grid environment, access is granted by a dedicated CEs. The status of the evaluation, feedback received from the experiments and the status of the migration will be reviewed, and the status of virtualization of services at CERN will be reported. Beyond this, the migration to a new operating system also offers an excellent opportunity to upgrade the fabric infrastructure used to manage the servers.

  13. 29 CFR 2560.502c-5 - Civil penalties under section 502(c)(5).

    Science.gov (United States)

    2010-07-01

    ... Act) that is not a group health plan, and that provides benefits consisting of medical care (within... section 502(c)(5) of the Act for each failure or refusal to file a completed report required to be filed...). (2) For purposes of this section, a failure or refusal to file the report required to be filed under...

  14. Theoretical study of the decomposition pathways and products of C5- perfluorinated ketone (C5 PFK)

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Yuwei; Wang, Xiaohua, E-mail: xhw@mail.xjtu.edu.cn, E-mail: mzrong@mail.xjtu.edu.cn; Li, Xi; Yang, Aijun; Wu, Yi; Rong, Mingzhe, E-mail: xhw@mail.xjtu.edu.cn, E-mail: mzrong@mail.xjtu.edu.cn [State Key Laboratory of Electrical Insulation and Power Equipment, Xi’an Jiaotong University, No. 28 XianNing West Road, Xi’an, Shaanxi Province 710049 (China); Han, Guohui; Lu, Yanhui [Pinggao Group Co. Ltd., Pingdingshan, Henan Province 467001 (China)

    2016-08-15

    Due to the high global warming potential (GWP) and increasing environmental concerns, efforts on searching the alternative gases to SF{sub 6}, which is predominantly used as insulating and interrupting medium in high-voltage equipment, have become a hot topic in recent decades. Overcoming the drawbacks of the existing candidate gases, C5- perfluorinated ketone (C5 PFK) was reported as a promising gas with remarkable insulation capacity and the low GWP of approximately 1. Experimental measurements of the dielectric strength of this novel gas and its mixtures have been carried out, but the chemical decomposition pathways and products of C5 PFK during breakdown are still unknown, which are the essential factors in evaluating the electric strength of this gas in high-voltage equipment. Therefore, this paper is devoted to exploring all the possible decomposition pathways and species of C5 PFK by density functional theory (DFT). The structural optimizations, vibrational frequency calculations and energy calculations of the species involved in a considered pathway were carried out with DFT-(U)B3LYP/6-311G(d,p) method. Detailed potential energy surface was then investigated thoroughly by the same method. Lastly, six decomposition pathways of C5 PFK decomposition involving fission reactions and the reactions with a transition states were obtained. Important intermediate products were also determined. Among all the pathways studied, the favorable decomposition reactions of C5 PFK were found, involving C-C bond ruptures producing Ia and Ib in pathway I, followed by subsequent C-C bond ruptures and internal F atom transfers in the decomposition of Ia and Ib presented in pathways II + III and IV + V, respectively. Possible routes were pointed out in pathway III and lead to the decomposition of IIa, which is the main intermediate product found in pathway II of Ia decomposition. We also investigated the decomposition of Ib, which can undergo unimolecular reactions to give the

  15. Periplasmic Acid Stress Increases Cell Division Asymmetry (Polar Aging of Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Michelle W Clark

    Full Text Available Under certain kinds of cytoplasmic stress, Escherichia coli selectively reproduce by distributing the newer cytoplasmic components to new-pole cells while sequestering older, damaged components in cells inheriting the old pole. This phenomenon is termed polar aging or cell division asymmetry. It is unknown whether cell division asymmetry can arise from a periplasmic stress, such as the stress of extracellular acid, which is mediated by the periplasm. We tested the effect of periplasmic acid stress on growth and division of adherent single cells. We tracked individual cell lineages over five or more generations, using fluorescence microscopy with ratiometric pHluorin to measure cytoplasmic pH. Adherent colonies were perfused continually with LBK medium buffered at pH 6.00 or at pH 7.50; the external pH determines periplasmic pH. In each experiment, cell lineages were mapped to correlate division time, pole age and cell generation number. In colonies perfused at pH 6.0, the cells inheriting the oldest pole divided significantly more slowly than the cells inheriting the newest pole. In colonies perfused at pH 7.50 (near or above cytoplasmic pH, no significant cell division asymmetry was observed. Under both conditions (periplasmic pH 6.0 or pH 7.5 the cells maintained cytoplasmic pH values at 7.2-7.3. No evidence of cytoplasmic protein aggregation was seen. Thus, periplasmic acid stress leads to cell division asymmetry with minimal cytoplasmic stress.

  16. Role of C5 Activation Products in Sepsis

    Directory of Open Access Journals (Sweden)

    Peter A. Ward

    2010-01-01

    Full Text Available Complement activation products are known to be generated in the setting of both experimental and human sepsis. C5 activation products (C5a anaphylatoxin and the membrane attack complex [MAC] C5b-9 are generated during sepsis following infusion of endotoxin, or after cecal ligation and puncture (CLP, which produces polymicrobial sepsis. C5a reacts with its receptors C5aR and C5L2 in a manner that creates the “cytokine storm”, and is associated with development of multiorgan failure (MOF. A number of other complications arising from the interaction of C5a with its receptors include apoptosis of lymphoid cells, loss of innate immune functions of neutrophils (PMNs, polymorphonuclear leukocytes, cardiomyopathy, disseminated intravascular coagulation, and complications associated with MOF. Neutralization of C5a in vivo or absence/blockade of C5a receptors greatly reduces the adverse events in the setting of sepsis, markedly attenuates MOF, and greatly improves survival. Regarding the possible role of C5b-9 in sepsis, the literature is conflicting. Some studies suggest that C5b-9 is protective, while other studies suggest the contrary. Clearly, in human sepsis, C5a and its receptors may be logical targets for interception.

  17. 26 CFR 1.381(c)(5)-1 - Inventories.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 4 2010-04-01 2010-04-01 false Inventories. 1.381(c)(5)-1 Section 1.381(c)(5)-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Insolvency Reorganizations § 1.381(c)(5)-1 Inventories. (a) Carryover requirement—(1...

  18. Interaction between bacterial outer membrane proteins and periplasmic quality control factors: a kinetic partitioning mechanism.

    Science.gov (United States)

    Wu, Si; Ge, Xi; Lv, Zhixin; Zhi, Zeyong; Chang, Zengyi; Zhao, Xin Sheng

    2011-09-15

    The OMPs (outer membrane proteins) of Gram-negative bacteria have to be translocated through the periplasmic space before reaching their final destination. The aqueous environment of the periplasmic space and high permeability of the outer membrane engender such a translocation process inevitably challenging. In Escherichia coli, although SurA, Skp and DegP have been identified to function in translocating OMPs across the periplasm, their precise roles and their relationship remain to be elucidated. In the present paper, by using fluorescence resonance energy transfer and single-molecule detection, we have studied the interaction between the OMP OmpC and these periplasmic quality control factors. The results of the present study reveal that the binding rate of OmpC to SurA or Skp is much faster than that to DegP, which may lead to sequential interaction between OMPs and different quality control factors. Such a kinetic partitioning mechanism for the chaperone-substrate interaction may be essential for the quality control of the biogenesis of OMPs.

  19. Role of anionic charges of periplasmic glucans of Shigella flexneri in overcoming detergent stress

    Science.gov (United States)

    Osmoregulated periplasmic glucans (OPGs) are synthesized by the members of the family Enterobacteriaceae when grown under low osmotic growth conditions. Enteropathogens such as Shigella flexneri spend considerable time outside the host environment such as irrigation waters where low nutrient low os...

  20. Association of Immune and Metabolic Receptors C5aR and C5L2 with Adiposity in Women

    Science.gov (United States)

    Rezvani, Reza; Gupta, Abhishek; Marceau, Picard; Tchernof, André

    2014-01-01

    Adipose tissue receptors C5aR and C5L2 and their heterodimerization/functionality and interaction with ligands C5a and acylation stimulating protein (ASP) have been evaluated in cell and rodent studies. Their contribution to obesity factors in humans remains unclear. We hypothesized that C5a receptors, classically required for host defense, are also associated with adiposity. Anthropometry and fasting blood parameters were measured in 136 women divided by body mass index (BMI): normal/overweight (≤30 kg/m2; n = 34), obese I (≤45 kg/m2; n = 33), obese II (≤51 kg/m2; n = 33), and obese III (≤80 kg/m2; n = 36). Subcutaneous and omental adipose tissue C5aR and C5L2 expression were analysed. C5L2 expression was comparable between subcutaneous and omental across all BMI groups. Plasma ASP and ASP/omental C5L2 expression increased with BMI (P correlations between C5L2/C5aR and waist circumference, HDL-C, and adiponectin. Tissue and BMI differences in receptors and ligands, particularly in omental, suggest relationship to metabolic disturbances and highlight adipose-immune interactions. PMID:24523571

  1. Export of Cytochrome P450 105D1 to the Periplasmic Space of Escherichia coli

    OpenAIRE

    Kaderbhai, Mustak A.; Ugochukwu, Cynthia C.; Kelly, Steven L.; Lamb, David C.

    2001-01-01

    CYP105D1, a cytochrome P450 from Streptomyces griseus, was appended at its amino terminus to the secretory signal of Escherichia coli alkaline phosphatase and placed under the transcriptional control of the native phoA promoter. Heterologous expression in E. coli phosphate-limited medium resulted in abundant synthesis of recombinant CYP105D1 that was translocated across the bacterial inner membrane and processed to yield authentic, heme-incorporated P450 within the periplasmic space. Cell ext...

  2. Structure of a periplasmic glucose-binding protein from Thermotoga maritima

    International Nuclear Information System (INIS)

    Palani, Kandavelu; Kumaran, Desigan; Burley, Stephen K.; Swaminathan, Subramanyam

    2012-01-01

    The periplasmic glucose-binding protein from T. maritima consists of two domains with the ligand β-d-glucose buried between them. The two domains adopt a closed conformation. ABC transport systems have been characterized in organisms ranging from bacteria to humans. In most bacterial systems, the periplasmic component is the primary determinant of specificity of the transport complex as a whole. Here, the X-ray crystal structure of a periplasmic glucose-binding protein (GBP) from Thermotoga maritima determined at 2.4 Å resolution is reported. The molecule consists of two similar α/β domains connected by a three-stranded hinge region. In the current structure, a ligand (β-d-glucose) is buried between the two domains, which have adopted a closed conformation. Details of the substrate-binding sites revealed features that determine substrate specificity. In toto, ten residues from both domains form eight hydrogen bonds to the bound sugar and four aromatic residues (two from each domain) stabilize the substrate through stacking interactions

  3. Properties of the periplasmic ModA molybdate-binding protein of Escherichia coli.

    Science.gov (United States)

    Rech, S; Wolin, C; Gunsalus, R P

    1996-02-02

    The modABCD operon, located at 17 min on the Escherichia coli chromosome, encodes the protein components of a high affinity molybdate uptake system. Sequence analysis of the modA gene (GenBank L34009) predicts that it encodes a periplasmic binding protein based on the presence of a leader-like sequence at its N terminus. To examine the properties of the ModA protein, the modA structural gene was overexpressed, and its product was purified. The ModA protein was localized to the periplasmic space of the cell, and it was released following a gentle osmotic shock. The N-terminal sequence of ModA confirmed that a leader region of 24 amino acids was removed upon export from the cell. The apparent size of ModA is 31.6 kDa as determined by gel sieve chromatography, whereas it is 22.5 kDa when examined by SDS-polyacrylamide gel electrophoresis. A ligand-dependent protein mobility shift assay was devised using a native polyacrylamide gel electrophoresis protocol to examine binding of molybdate and other anions to the ModA periplasmic protein. Whereas molybdate and tungstate were bound with high affinity (approximately 5 microM), sulfate, chromate, selenate, phosphate, and chlorate did not bind even when tested at 2 mM. A UV spectral assay revealed apparent Kd values of binding for molybdate and tungstate of 3 and 7 microM, respectively. Strains defective in the modA gene were unable to transport molybdate unless high levels of the anion were supplied in the medium. Therefore the modA gene product is essential for high affinity molybdate uptake by the cell. Tungstate interference of molybdate acquisition by the cell is apparently due in part to the high affinity of the ModA protein for this anion.

  4. Periplasmic expression of soluble single chain T cell receptors is rescued by the chaperone FkpA

    Directory of Open Access Journals (Sweden)

    Bogen Bjarne

    2010-02-01

    Full Text Available Abstract Background Efficient expression systems exist for antibody (Ab molecules, which allow for characterization of large numbers of individual Ab variants. In contrast, such expression systems have been lacking for soluble T cell receptors (TCRs. Attempts to generate bacterial systems have generally resulted in low yields and material which is prone to aggregation and proteolysis. Here we present an optimized periplasmic bacterial expression system for soluble single chain (sc TCRs. Results The effect of 1 over-expression of the periplasmic chaperon FkpA, 2 culture conditions and 3 molecular design was investigated. Elevated levels of FkpA allowed periplasmic soluble scTCR expression, presumably by preventing premature aggregation and inclusion body formation. Periplasmic expression enables disulphide bond formation, which is a prerequisite for the scTCR to reach its correct fold. It also enables quick and easy recovery of correctly folded protein without the need for time-consuming downstream processing. Expression without IPTG induction further improved the periplasmic expression yield, while addition of sucrose to the growth medium showed little effect. Shaker flask yield of mg levels of active purified material was obtained. The Vαβ domain orientation was far superior to the Vβα domain orientation regarding monomeric yield of functionally folded molecules. Conclusion The general expression regime presented here allows for rapid production of soluble scTCRs and is applicable for 1 high yield recovery sufficient for biophysical characterization and 2 high throughput screening of such molecules following molecular engineering.

  5. Protective effects of C5a blockade in sepsis

    DEFF Research Database (Denmark)

    Czermak, B J; Sarma, V; Pierson, C L

    1999-01-01

    in vitro had greatly reduced production of H2O2, which is known to be essential for the bactericidal function of neutrophils. In contrast, when companion CLP rats were treated with IgG antibody against C5a, survival rates were significantly improved, levels of bacteremia were considerably reduced...

  6. Selective terminal C–C scission of C5-carbohydrates

    NARCIS (Netherlands)

    Klis, van der F.; Gootjes, L.; Haveren, van J.; Es, van D.S.; Bitter, J.H.

    2015-01-01

    The selective catalytic production of C4-tetritols (erythritol and threitol) from C5-sugars is an attractive route for the conversion of non-digestible sugars to C4-building blocks from agro residues. Here we show that an unprecedented high selectivity of 20–25% C4-tertritols can be achieved under

  7. HSV neutralization by the microbicidal candidate C5A

    NARCIS (Netherlands)

    de Witte, L.; Bobardt, M.D.; Chatterji, U.; van Loenen, F.B.; Verjans, G.M.G.M.; Geijtenbeek, T.B.H.; Gallay, P.A.

    2011-01-01

    Genital herpes is a major risk factor in acquiring human immunodeficiency virus type-1 (HIV-1) infection and is caused by both Herpes Simplex virus type 1 (HSV-1) and HSV-2. The amphipathic peptide C5A, derived from the non-structural hepatitis C virus (HCV) protein 5A, was shown to prevent HIV-1

  8. HSV neutralization by the microbicidal candidate C5A

    NARCIS (Netherlands)

    L. de Witte (Lot); M.D. Bobardt (Michael); U. Chatterji (Udayan); F.B. van Loenen (Freek); G.M.G.M. Verjans (George); T.B.H. Geijtenbeek (Teunis); P.A. Gallay (Philippe)

    2011-01-01

    textabstractGenital herpes is a major risk factor in acquiring human immunodeficiency virus type-1 (HIV-1) infection and is caused by both Herpes Simplex virus type 1 (HSV-1) and HSV-2. The amphipathic peptide C5A, derived from the non-structural hepatitis C virus (HCV) protein 5A, was shown to

  9. Synthetic of Zr2Al3C5 material

    International Nuclear Information System (INIS)

    Leela-Adisorn, U.; Yamaguchi, A.

    2005-01-01

    Synthesis method of Zr 2 Al 3 C 5 via solid state reaction between Al, ZrC and carbon powder was studied. Al-ZrC-C compact with equivalent mol ratio of Zr 2 Al 3 C 5 was heated up to 1600 C in Ar atmosphere for 1 h and 4 h but ZrC phase still existed as major phase with very small amount of Zr 2 Al 3 C 5 . Because ZrC started to oxidize at low temperature under very low oxygen partial pressure, the same mol ratio of Al-ZrC-C compact was heated at 1600 C in vacuum for 1 h as parallel test. After firing in vacuum, some carbon still exist with small amount of AlZrC 2 occurred with Zr 2 Al 3 C 5 as a main phase, but no ZrC was found. Different result from firing in Ar atmosphere and in vacuum had been discussed here. It was believed that very small amount of impurities in Ar had some effect on the formation of Al-Zr-C compound. The effect of very small amount of impurities in Ar was studied by thermal analysis (DTA/TG) and XRD. It was found that very small amount of impurities in Ar has effect on the reaction between Al, ZrC and carbon by diffusion through the surface and form Zr-C-O-N solid solution. This solid solution cannot differentiate from ZrC by XRD. With help of thermal analysis method (DTA/TG), Zr-C-O-N solid solution can be differentiated from ZrC. Therefore, synthesis of Al-Zr-C compound should be done in vacuum. Zr 2 Al 3 C 5 can be prepared from mixture of Al-ZrC-C with excess amount of Al at 1600 C for 1 h. (orig.)

  10. Bacterial periplasmic sialic acid-binding proteins exhibit a conserved binding site

    Energy Technology Data Exchange (ETDEWEB)

    Gangi Setty, Thanuja [Institute for Stem Cell Biology and Regenerative Medicine, NCBS Campus, GKVK Post, Bangalore, Karnataka 560 065 (India); Cho, Christine [Carver College of Medicine, University of Iowa, Iowa City, IA 52242-1109 (United States); Govindappa, Sowmya [Institute for Stem Cell Biology and Regenerative Medicine, NCBS Campus, GKVK Post, Bangalore, Karnataka 560 065 (India); Apicella, Michael A. [Carver College of Medicine, University of Iowa, Iowa City, IA 52242-1109 (United States); Ramaswamy, S., E-mail: ramas@instem.res.in [Institute for Stem Cell Biology and Regenerative Medicine, NCBS Campus, GKVK Post, Bangalore, Karnataka 560 065 (India)

    2014-07-01

    Structure–function studies of sialic acid-binding proteins from F. nucleatum, P. multocida, V. cholerae and H. influenzae reveal a conserved network of hydrogen bonds involved in conformational change on ligand binding. Sialic acids are a family of related nine-carbon sugar acids that play important roles in both eukaryotes and prokaryotes. These sialic acids are incorporated/decorated onto lipooligosaccharides as terminal sugars in multiple bacteria to evade the host immune system. Many pathogenic bacteria scavenge sialic acids from their host and use them for molecular mimicry. The first step of this process is the transport of sialic acid to the cytoplasm, which often takes place using a tripartite ATP-independent transport system consisting of a periplasmic binding protein and a membrane transporter. In this paper, the structural characterization of periplasmic binding proteins from the pathogenic bacteria Fusobacterium nucleatum, Pasteurella multocida and Vibrio cholerae and their thermodynamic characterization are reported. The binding affinities of several mutations in the Neu5Ac binding site of the Haemophilus influenzae protein are also reported. The structure and the thermodynamics of the binding of sugars suggest that all of these proteins have a very well conserved binding pocket and similar binding affinities. A significant conformational change occurs when these proteins bind the sugar. While the C1 carboxylate has been identified as the primary binding site, a second conserved hydrogen-bonding network is involved in the initiation and stabilization of the conformational states.

  11. Bacterial periplasmic sialic acid-binding proteins exhibit a conserved binding site

    International Nuclear Information System (INIS)

    Gangi Setty, Thanuja; Cho, Christine; Govindappa, Sowmya; Apicella, Michael A.; Ramaswamy, S.

    2014-01-01

    Structure–function studies of sialic acid-binding proteins from F. nucleatum, P. multocida, V. cholerae and H. influenzae reveal a conserved network of hydrogen bonds involved in conformational change on ligand binding. Sialic acids are a family of related nine-carbon sugar acids that play important roles in both eukaryotes and prokaryotes. These sialic acids are incorporated/decorated onto lipooligosaccharides as terminal sugars in multiple bacteria to evade the host immune system. Many pathogenic bacteria scavenge sialic acids from their host and use them for molecular mimicry. The first step of this process is the transport of sialic acid to the cytoplasm, which often takes place using a tripartite ATP-independent transport system consisting of a periplasmic binding protein and a membrane transporter. In this paper, the structural characterization of periplasmic binding proteins from the pathogenic bacteria Fusobacterium nucleatum, Pasteurella multocida and Vibrio cholerae and their thermodynamic characterization are reported. The binding affinities of several mutations in the Neu5Ac binding site of the Haemophilus influenzae protein are also reported. The structure and the thermodynamics of the binding of sugars suggest that all of these proteins have a very well conserved binding pocket and similar binding affinities. A significant conformational change occurs when these proteins bind the sugar. While the C1 carboxylate has been identified as the primary binding site, a second conserved hydrogen-bonding network is involved in the initiation and stabilization of the conformational states

  12. Alginate-modifying enzymes: Biological roles and biotechnological uses

    Directory of Open Access Journals (Sweden)

    Helga eErtesvåg

    2015-05-01

    Full Text Available Alginate denotes a group of industrially important 1-4-linked biopolymers composed of the C-5-epimers β-D-mannuronic acid (M and α-L-guluronic acid (G. The polysaccharide is manufactured from brown algae where it constitutes the main structural cell wall polymer. The physical properties of a given alginate molecule, e.g. gel-strength, water-binding capacity, viscosity and biocompatibility, are determined by polymer length, the relative amount and distribution of G residues and the acetyl content, all of which are controlled by alginate modifying enzymes. Alginate has also been isolated from some bacteria belonging to the genera Pseudomonas and Azotobacter, and bacterially synthesized alginate may be O-acetylated at O-2 and/or O-3. Initially, alginate is synthesized as polymannuronic acid, and some M residues are subsequently epimerized to G residues. In bacteria a mannuronan C-5-epimerase (AlgG and an alginate acetylase (AlgX are integral parts of the protein complex necessary for alginate polymerisation and export. All alginate-producing bacteria use periplasmic alginate lyases to remove alginate molecules aberrantly released to the periplasm. Alginate lyases are also produced by organisms that utilize alginate as carbon source. Most alginate-producing organisms encode more than one mannuronan C-5 epimerase, each introducing its specific pattern of G residues. Acetylation protects against further epimerization and from most alginate lyases. One enzyme with alginate deacetylase activity from Pseudomonas syringae has been reported. Functional and structural studies reveal that alginate lyases and epimerases have related enzyme mechanisms and catalytic sites. Alginate lyases are now utilized as tools for alginate characterization. Secreted epimerases have been shown to function well in vitro, and have been engineered further in order to obtain enzymes that can provide alginates with new and desired properties for use in medical and

  13. Development of a high yielding E. coli periplasmic expression system for the production of humanized Fab' fragments.

    Science.gov (United States)

    Ellis, Mark; Patel, Pareshkumar; Edon, Marjory; Ramage, Walter; Dickinson, Robert; Humphreys, David P

    2017-01-01

    Humanized Fab' fragments may be produced in the periplasm of Escherichia coli but can be subject to degradation by host cell proteases. In order to increase Fab' yield and reduce proteolysis we developed periplasmic protease deficient strains of E. coli. These strains lacked the protease activity of Tsp, protease III and DegP. High cell density fermentations indicated Tsp deficient strains increased productivity two fold but this increase was accompanied by premature cell lysis soon after the induction of Fab' expression. To overcome the reduction in cell viability we introduced suppressor mutations into the spr gene. The mutations partially restored the wild type phenotype of the cells. Furthermore, we coexpressed a range of periplasmic chaperone proteins with the Fab', DsbC had the most significant impact, increasing humanized Fab' production during high cell density fermentation. When DsbC coexpression was combined with a Tsp deficient spr strain we observed an increase in yield and essentially restored "wild type" cell viability. We achieved a final periplasmic yield of over 2.4g/L (final cell density OD 600 105), 40 h post Fab' induction with minimal cell lysis.The data suggests that proteolysis, periplasm integrity, protein folding and disulphide bond formation are all potential limiting steps in the production of Fab' fragments in the periplasm of E. coli. In this body of work, we have addressed these limiting steps by utilizing stabilized protease deficient strains and chaperone coexpression. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 33:212-220, 2017. © 2016 American Institute of Chemical Engineers.

  14. The large first periplasmic loop of SecD and SecF plays an important role in SecDF functioning

    NARCIS (Netherlands)

    Nouwen, N; Piwowarek, M; Berrelkamp, G; Driessen, AJM

    A remarkable feature of proteins of the SecD and SecF family involved in protein translocation is that they possess a very large first periplasmic domain. Here we report that this large first periplasmic domain is not required for the SecD-SecF interaction but that it is important for catalyzing

  15. Expression, crystallization and preliminary X-ray analysis of the periplasmic stress sensory protein RseB from Escherichia coli

    International Nuclear Information System (INIS)

    Wollmann, Petra; Zeth, Kornelius

    2006-01-01

    The periplasmic stress protein RseB from E. coli was cloned, expressed and crystallized. Crystallographic data are presented and structure solution using the multiple isomorphous replacement approach (MIR) is in progress. Sensing external stress in the bacterial periplasm and signal transduction to the cytoplasm are important functions of the CpxAR, Bae and σ E signalling pathways. In Escherichia coli, the σ E pathway can be activated through degradation of the antisigma factor RseA by DegS and YaeL. The periplasmic protein RseB plays an important role in this pathway by exerting a direct or indirect negative effect on YaeL cleavage efficiency. RseB from E. coli, missing the periplasmic signal sequence (RseB ΔN ), was cloned, expressed, purified and crystallized. Crystals were obtained in two different forms belonging to space group P42 1 2 (form I) and C222 1 (form II) and diffracted to 2.8 and 2.4 Å resolution, respectively. In crystal form I two copies of the protein were located in the asymmetric unit according to heavy-atom analysis, while crystal form II contained three copies

  16. The chlamydial periplasmic stress response serine protease cHtrA is secreted into host cell cytosol

    Directory of Open Access Journals (Sweden)

    Flores Rhonda

    2011-04-01

    Full Text Available Abstract Background The periplasmic High Temperature Requirement protein A (HtrA plays important roles in bacterial protein folding and stress responses. However, the role of chlamydial HtrA (cHtrA in chlamydial pathogenesis is not clear. Results The cHtrA was detected both inside and outside the chlamydial inclusions. The detection was specific since both polyclonal and monoclonal anti-cHtrA antibodies revealed similar intracellular labeling patterns that were only removed by absorption with cHtrA but not control fusion proteins. In a Western blot assay, the anti-cHtrA antibodies detected the endogenous cHtrA in Chlamydia-infected cells without cross-reacting with any other chlamydial or host cell antigens. Fractionation of the infected cells revealed cHtrA in the host cell cytosol fraction. The periplasmic cHtrA protein appeared to be actively secreted into host cell cytosol since no other chlamydial periplasmic proteins were detected in the host cell cytoplasm. Most chlamydial species secreted cHtrA into host cell cytosol and the secretion was not inhibitable by a type III secretion inhibitor. Conclusion Since it is hypothesized that chlamydial organisms possess a proteolysis strategy to manipulate host cell signaling pathways, secretion of the serine protease cHtrA into host cell cytosol suggests that the periplasmic cHtrA may also play an important role in chlamydial interactions with host cells.

  17. Sucrose dependent mineral phosphate solubilization in Enterobacter asburiae PSI3 by heterologous overexpression of periplasmic invertases.

    Science.gov (United States)

    Kumar, Chanchal; Wagh, Jitendra; Archana, G; Naresh Kumar, G

    2016-12-01

    Enterobacter asburiae PSI3 solubilizes mineral phosphates in the presence of glucose by the secretion of gluconic acid generated by the action of a periplasmic pyrroloquinoline quinone dependent glucose dehydrogenase. In order to achieve mineral phosphate solubilization phenotype in the presence of sucrose, plasmids pCNK4 and pCNK5 containing genes encoding the invertase enzyme of Zymomonas mobilis (invB) and of Saccharomyces cerevisiae (suc2) under constitutive promoters were constructed with malE signal sequence (in case of invB alone as the suc2 is secreted natively). When introduced into E. asburiae PSI3, E. a. (pCNK4) and E. a. (pCNK5) transformants secreted 21.65 ± 0.94 and 22 ± 1.3 mM gluconic acid, respectively, in the presence of 75 mM sucrose and they also solubilized 180 ± 4.3 and 438 ± 7.3 µM P from the rock phosphate. In the presence of a mixture of 50 mM sucrose and 25 mM glucose, E. a. (pCNK5) secreted 34 ± 2.3 mM gluconic acid and released 479 ± 8.1 µM P. Moreover, in the presence of a mixture of eight sugars (10 mM each) in the medium, E. a. (pCNK5) released 414 ± 5.3 µM P in the buffered medium. Thus, this study demonstrates incorporation of periplasmic invertase imparted P solubilization ability to E. asburiae PSI3 in the presence of sucrose and mixture of sugars.

  18. Type 1 Does The Two-Step: Type 1 Secretion Substrates With A Functional Periplasmic Intermediate.

    Science.gov (United States)

    Smith, Timothy J; Sondermann, Holger; O'Toole, George A

    2018-06-04

    Bacteria have evolved several secretion strategies for polling and responding to environmental flux and insult. Of these, the type 1 secretion system (T1SS) is known to secrete an array of biologically diverse proteins - from small < 10 kDa bacteriocins to gigantic adhesins with a mass over 1 MDa. For the last several decades T1SS have been characterized as a one-step translocation strategy whereby the secreted substrate is transported directly into the extracellular environment from the cytoplasm with no periplasmic intermediate. Recent phylogenetic, biochemical, and genetic evidence point to a distinct sub-group of T1SS machinery linked with a bacterial transglutaminase-like cysteine proteinase (BTLCP), which uses a two-step secretion mechanism. BTLCP-linked T1SS transport a class of repeats-in-toxin (RTX) adhesins that are critical for biofilm formation. The prototype of this RTX adhesin group, LapA of Pseudomonas fluorescens Pf0-1, uses a novel N-terminal retention module to anchor the adhesin at the cell surface as a secretion intermediate threaded through the outer membrane-localized, TolC-like protein LapE. This secretion intermediate is post-translationally cleaved by the BTLCP family LapG protein to release LapA from its cognate T1SS pore. Thus, secretion of LapA and related RTX adhesins into the extracellular environment appears to be a T1SS-mediated, two-step process that involves a periplasmic intermediate. In this review, we contrast the T1SS machinery and substrates of the BLTCP-linked two-step secretion process with those of the classical one-step T1SS to better understand the newly recognized and expanded role of this secretion machinery. Copyright © 2018 American Society for Microbiology.

  19. Secretion of Bacterial Lipoproteins: Through the Cytoplasmic Membrane, the Periplasm and Beyond

    Science.gov (United States)

    Zückert, Wolfram R.

    2014-01-01

    Bacterial lipoproteins are peripherally anchored membrane proteins that play a variety of roles in bacterial physiology and virulence in monoderm (single membrane-enveloped, e.g., grampositive) and diderm (double membrane-enveloped, e.g., gram-negative) bacteria. After export of prolipoproteins through the cytoplasmic membrane, which occurs predominantly but not exclusively via the general secretory or Sec pathway, the proteins are lipid-modified at the cytoplasmic membrane in a multistep process that involves sequential modification of a cysteine residue and cleavage of the signal peptide by the signal II peptidase Lsp. In both monoderms and diderms, signal peptide processing is preceded by acylation with a diacylglycerol through preprolipoprotein diacylglycerol transferase (Lgt). In diderms but also some monoderms, lipoproteins are further modified with a third acyl chain through lipoprotein N-acyl transferase (Lnt). Fully modified lipoproteins that are destined to be anchored in the inner leaflet of the outer membrane (OM) are selected, transported and inserted by the Lol (lipoprotein outer membrane localization) pathway machinery, which consists of the inner-membrane (IM) ABC transporterlike LolCDE complex, the periplasmic LolA chaperone and the OM LolB lipoprotein receptor. Retention of lipoproteins in the cytoplasmic membrane results from Lol avoidance signals that were originally described as the “+2 rule”. Surface localization of lipoproteins in diderms is rare in most bacteria, with the exception of several spirochetal species. Type 2 (T2SS) and type 5 (T5SS) secretion systems are involved in secretion of specific surface lipoproteins of γ-proteobacteria. In the model spirochete Borrelia burgdorferi, surface lipoprotein secretion does not follow established sorting rules, but remains dependent on N-terminal peptide sequences. Secretion through the outer membrane requires maintenance of lipoproteins in a translocation-competent unfolded conformation

  20. Typing and grading of cytological category C5 breast lesions

    International Nuclear Information System (INIS)

    Zafar, N.; Jamal, S.; Mamoon, N.; Luqman, M.; Anwar, M.

    2005-01-01

    Objective: To determine the tumour type, cytological grade and nuclear grade on fine-needle aspiration smears in cytological category C5 breast lesions and compare them with histopathological findings. Subjects and Methods: Out of all patients referred to AFIP, Rawalpindi for fine-needle aspiration of breast masses, those adjudged C5 (malignant) were chosen for this study. History, clinical details and mammographic findings were noted. Aspirated smears were examined and an attempt was made to ascertain tumour type, cytological grade and nuclear grade. On excision of these lesions, the cytological findings were compared with those on paraffin-embedded histological sections. Results: A total of 71 patients were included in this study. Of these, 64 (90.14%) were cytologically diagnosed as ductal carcinoma, 4 (5.63%) lobular carcinoma, 2 (2.82%) mucinous carcinoma and 1 (1.41%) as medullary carcinoma. Seventy (98.60%) tumours were correctly typed on aspiration smears. Sixty-eight (95.77%) cases were cytologically graded with accuracy. Nuclear grading was even better on cytology and, excluding one malignant lymphoma, all 70 (100%) smears were assessed correctly. Conclusion: Overall efficiency of the tumour typing, cytological grading and nuclear grading on aspirated material turned out to be quite accurate. In expert hands, cytological examination can be of great help in pre-operative planning and in cases where tumour morphology in paraffin-embedded material has been distorted by neo-adjuvant therapy prior to excision. (author)

  1. C5a and C5aR are elevated in joints of rheumatoid and psoriatic arthritis patients, and C5aR blockade attenuates leukocyte migration to synovial fluid

    DEFF Research Database (Denmark)

    Hornum, Lars; Hansen, Anker Jon; Tornehave, Ditte

    2017-01-01

    synovial fluid was significantly inhibited by anti-C5aR. The data support that the C5a-C5aR axis may be driving the infiltration of inflammatory cells into the synovial fluid and synovium in both rheumatoid and psoriatic arthritis, and suggest that C5a or C5aR may be a promising treatment target in both...... a Boyden chamber. Appropriate statistical tests were applied for comparisons. C5aR+ cells were detected in most rheumatoid arthritis, in all psoriatic arthritis, but not in non-inflammatory control synovia. C5aR+ cells were primarily neutrophils and macrophages. C5aR+ macrophages were mainly found...

  2. Characterization of the periplasmic redox network that sustains the versatile anaerobic metabolism of Shewanella oneidensis MR-1

    Directory of Open Access Journals (Sweden)

    Mónica N. Alves

    2015-06-01

    Full Text Available The versatile anaerobic metabolism of the Gram-negative bacterium Shewanella oneidensis MR-1 (SOMR-1 relies on a multitude of redox proteins found in its periplasm. Most are multiheme cytochromes that carry electrons to terminal reductases of insoluble electron acceptors located at the cell surface, or bona fide terminal reductases of soluble electron acceptors. In this study, the interaction network of several multiheme cytochromes was explored by a combination of NMR spectroscopy, activity assays followed by UV-visible spectroscopy and comparison of surface electrostatic potentials. From these data the small tetraheme cytochrome (STC emerges as the main periplasmic redox shuttle in SOMR-1. It accepts electrons from CymA and distributes them to a number of terminal oxidoreductases involved in the respiration of various compounds. STC is also involved in the electron transfer pathway to reduce nitrite by interaction with the octaheme tetrathionate reductase (OTR, but not with cytochrome c nitrite reductase (ccNiR. In the main pathway leading the metal respiration STC pairs with flavocytochrome c (FccA, the other major periplasmic cytochrome, which provides redundancy in this important pathway. The data reveals that the two proteins compete for the binding site at the surface of MtrA, the decaheme cytochrome inserted on the periplasmic side of the MtrCAB-OmcA outer-membrane complex. However, this is not observed for the MtrA homologues. Indeed, neither STC nor FccA interact with MtrD, the best replacement for MtrA, and only STC is able to interact with the decaheme cytochrome DmsE of the outer-membrane complex DmsEFABGH. Overall, these results shown that STC plays a central role in the anaerobic respiratory metabolism of SOMR-1. Nonetheless, the trans-periplasmic electron transfer chain is functionally resilient as a consequence of redundancies that arise from the presence of alternative pathways that bypass/compete with STC.

  3. Bis(tetramethylcyclopentadienyl)titanium chemistry. Molecular structures of [(C(5)HMe(4))(mu-eta(1) : eta(5)-C(5)Me(4))Ti](2) and [(C(5)HMe(4))(2)Ti]N-2(2)

    NARCIS (Netherlands)

    deWolf, JM; Blaauw, R; Meetsma, A; Teuben, JH; Gyepes, R; Varga, [No Value; Mach, K; Veldman, N; Spek, AL

    1996-01-01

    Thermolysis of bis(tetramethylcyclopentadienyl)-stabilized titanium(III) compounds (C(5)HMe(4))(2)TiR (R = Me (2), Ph (3)) yields, in marked contrast with the bis(pentamethylcyclopentadienyl) analog, the dimeric product [(C(5)HMe(4))(mu-eta(1):eta(5)-C(5)Me(4))Ti](2) (4), With a bridging metalated

  4. C-5 Propynyl Modifications Enhance the Mechanical Stability of DNA.

    Science.gov (United States)

    Aschenbrenner, Daniela; Baumann, Fabian; Milles, Lukas F; Pippig, Diana A; Gaub, Hermann E

    2015-07-20

    Increased thermal or mechanical stability of DNA duplexes is desired for many applications in nanotechnology or -medicine where DNA is used as a programmable building block. Modifications of pyrimidine bases are known to enhance thermal stability and have the advantage of standard base-pairing and easy integration during chemical DNA synthesis. Through single-molecule force spectroscopy experiments with atomic force microscopy and the molecular force assay we investigated the effect of pyrimidines harboring C-5 propynyl modifications on the mechanical stability of double-stranded DNA. Utilizing these complementary techniques, we show that propynyl bases significantly increase the mechanical stability if the DNA is annealed at high temperature. In contrast, modified DNA complexes formed at room temperature and short incubation times display the same stability as non-modified DNA duplexes. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Cloning, periplasmic expression, purification and structural characterization of human ribosomal protein L10

    International Nuclear Information System (INIS)

    Pereira, Larissa Miranda

    2009-01-01

    The ribosomal protein L10 (RP L10) is a strong candidate to be included in the class of tumor suppressor proteins. This protein, also denominated as QM, is known to participate in the binding of ribosomal subunits 60S and 40S and the translation of mRNAs. It has a molecular weight that varies between 24 and 26 kDa and an isoelectric point of (pI) 10.5. The sequence of the protein QM is highly conserved in mammals, plants, invertebrates, insects and yeast which indicates its critical functions in a cell. As a tumor suppressor, RP L10 has been studied in strains of Wilm's tumor (WT-1) and tumor cells in the stomach, where was observed a decrease in the amount of its mRNA. More recently, the RP L10 was found in low amounts in the early stages of prostate adenoma and showed some mutation in ovarian cancer, what indicates its role as a suppressor protein in the development of these diseases. It has also been described that this protein interacts with c-Jun and c-Yes inhibiting growth factors and consequently, cell division. This work has an important role on the establishment of soluble expression of QM to give base information for further studies on expression that aim to evaluate the specific regions where it acts binding the 60S and 40S ribosomal subunits and translation, as well as its binding to proto-oncogenes. The cDNA for QM protein was amplified by PCR and cloned into periplasmic expression vector p3SN8. The QM protein was expressed in E. coli BL21 (DE3) in the region of cytoplasm and periplasm, the best condition was obtained from the expression of the recombinant plasmid QM p1813 Q M at 25 degree C or 30 degree C, the soluble protein was obtained with small amounts of contaminants. The assays of secondary structure showed that the QM protein is predominantly alpha-helix, but when it loses the folding, this condition changes and the protein is replaced by β- sheet feature. (author)

  6. Cold adaptation of the mononuclear molybdoenzyme periplasmic nitrate reductase from the Antarctic bacterium Shewanella gelidimarina

    International Nuclear Information System (INIS)

    Simpson, Philippa J.L.; Codd, Rachel

    2011-01-01

    Highlights: ► Cold-adapted phenotype of NapA from the Antarctic bacterium Shewanella gelidimarina. ► Protein homology model of NapA from S. gelidimarina and mesophilic homologue. ► Six amino acid residues identified as lead candidates governing NapA cold adaptation. ► Molecular-level understanding of designing cool-temperature in situ oxyanion sensors. -- Abstract: The reduction of nitrate to nitrite is catalysed in bacteria by periplasmic nitrate reductase (Nap) which describes a system of variable protein subunits encoded by the nap operon. Nitrate reduction occurs in the NapA subunit, which contains a bis-molybdopterin guanine dinucleotide (Mo–MGD) cofactor and one [4Fe–4S] iron–sulfur cluster. The activity of periplasmic nitrate reductase (Nap) isolated as native protein from the cold-adapted (psychrophilic) Antarctic bacterium Shewanella gelidimarina (Nap Sgel ) and middle-temperature adapted (mesophilic) Shewanella putrefaciens (Nap Sput ) was examined at varied temperature. Irreversible deactivation of Nap Sgel and Nap Sput occurred at 54.5 and 65 °C, respectively. When Nap Sgel was preincubated at 21–70 °C for 30 min, the room-temperature nitrate reductase activity was maximal and invariant between 21 and 54 °C, which suggested that Nap Sgel was poised for optimal catalysis at modest temperatures and, unlike Nap Sput , did not benefit from thermally-induced refolding. At 20 °C, Nap Sgel reduced selenate at 16% of the rate of nitrate reduction. Nap Sput did not reduce selenate. Sequence alignment showed 46 amino acid residue substitutions in Nap Sgel that were conserved in NapA from mesophilic Shewanella, Rhodobacter and Escherichia species and could be associated with the Nap Sgel cold-adapted phenotype. Protein homology modeling of Nap Sgel using a mesophilic template with 66% amino acid identity showed the majority of substitutions occurred at the protein surface distal to the Mo–MGD cofactor. Two mesophilic ↔ psychrophilic

  7. Secretion of bacterial lipoproteins: through the cytoplasmic membrane, the periplasm and beyond.

    Science.gov (United States)

    Zückert, Wolfram R

    2014-08-01

    Bacterial lipoproteins are peripherally anchored membrane proteins that play a variety of roles in bacterial physiology and virulence in monoderm (single membrane-enveloped, e.g., gram-positive) and diderm (double membrane-enveloped, e.g., gram-negative) bacteria. After export of prolipoproteins through the cytoplasmic membrane, which occurs predominantly but not exclusively via the general secretory or Sec pathway, the proteins are lipid-modified at the cytoplasmic membrane in a multistep process that involves sequential modification of a cysteine residue and cleavage of the signal peptide by the signal II peptidase Lsp. In both monoderms and diderms, signal peptide processing is preceded by acylation with a diacylglycerol through preprolipoprotein diacylglycerol transferase (Lgt). In diderms but also some monoderms, lipoproteins are further modified with a third acyl chain through lipoprotein N-acyl transferase (Lnt). Fully modified lipoproteins that are destined to be anchored in the inner leaflet of the outer membrane (OM) are selected, transported and inserted by the Lol (lipoprotein outer membrane localization) pathway machinery, which consists of the inner-membrane (IM) ABC transporter-like LolCDE complex, the periplasmic LolA chaperone and the OM LolB lipoprotein receptor. Retention of lipoproteins in the cytoplasmic membrane results from Lol avoidance signals that were originally described as the "+2 rule". Surface localization of lipoproteins in diderms is rare in most bacteria, with the exception of several spirochetal species. Type 2 (T2SS) and type 5 (T5SS) secretion systems are involved in secretion of specific surface lipoproteins of γ-proteobacteria. In the model spirochete Borrelia burgdorferi, surface lipoprotein secretion does not follow established sorting rules, but remains dependent on N-terminal peptide sequences. Secretion through the outer membrane requires maintenance of lipoproteins in a translocation-competent unfolded conformation

  8. Crystallisation and Preliminary Crystallographic Analysis of Helicobacter pylori Periplasmic Binding Protein YckK

    Directory of Open Access Journals (Sweden)

    Mohammad Mizanur Rahman

    2017-10-01

    Full Text Available Helicobacter pylori infection can lead to the development of gastric and duodenal ulcers and gastric cancer. In recent years, the efficacy of the standard therapy has been falling, necessitating ongoing efforts to identify new drug targets. Due to their important role in chemotaxis and nutrient uptake, periplasmic binding proteins (PBPs represent potential targets for new antimicrobial agents that have not yet been fully explored and exploited. The H. pylori PBP YckK is homologous to polar amino acid-binding proteins from other bacteria. The yckK gene overlaps the gene tcyB—a gene annotated as a polar amino acid-transporting permease. Purified recombinant YckK behaved as a monomer in solution. Crystals of YckK were grown by the hanging drop vapour diffusion method using PEG 3350 as the precipitating agent. The crystals belong to the primitive triclinic space group P1 with unit cell parameters a = 63.0, b = 63.5, c = 74.6 Å, α = 72.5, β = 68.3, γ = 69.4°. X-ray diffraction data were collected to 1.8 Å resolution using synchrotron radiation. Molecular replacement using this data revealed that the asymmetric unit contains three subunits: two in the open and one in the closed conformation.

  9. A genetic screen reveals a periplasmic copper chaperone required for nitrite reductase activity in pathogenic Neisseria.

    Science.gov (United States)

    Jen, Freda E-C; Djoko, Karrera Y; Bent, Stephen J; Day, Christopher J; McEwan, Alastair G; Jennings, Michael P

    2015-09-01

    Under conditions of low oxygen availability, Neisseria meningitidis and Neisseria gonorrhoeae are able to respire via a partial denitrification pathway in which nitrite is converted to nitrous oxide. In this process, nitrite reductase (AniA), a copper (Cu)-containing protein converts nitrite to NO, and this product is converted to nitrous oxide by nitric oxide reductase (NorB). NorB also confers protection against toxic NO, and so we devised a conditional lethal screen, using a norB mutant, to identify mutants that were resistant to nitrite-dependent killing. After random-deletion mutagenesis of N. meningitidis, this genetic screen identified a gene encoding a Cu chaperone that is essential for AniA function, AccA. Purified AccA binds one Cu (I) ion and also possesses a second binding site for Cu (II). This novel periplasmic Cu chaperone (AccA) appears to be essential for provision of Cu ions to AniA of pathogenic Neisseria to generate an active nitrite reductase. Apart from the Neisseria genus, AccA is distributed across a wide range of environmental Proteobacteria species. © FASEB.

  10. Architecture and roles of periplasmic adaptor proteins in tripartite efflux assemblies.

    Directory of Open Access Journals (Sweden)

    Vassiliy N. Bavro

    2015-05-01

    Full Text Available Recent years have seen major advances in the structural understanding of the different components of tripartite efflux assemblies, which encompass the multidrug efflux (MDR pumps and type I secretion systems. The majority of these investigations have focused on the role played by the inner membrane transporters and the outer membrane factor (OMF, leaving the third component of the system – the Periplasmic Adaptor Proteins (PAPs - relatively understudied. Here we review the current state of knowledge of these versatile proteins which, far from being passive linkers between the OMF and the transporter, emerge as active architects of tripartite assemblies, and play diverse roles in the transport process. Recognition between the PAPs and OMFs is essential for pump assembly and function, and targeting this interaction may provide a novel avenue for combating multidrug resistance. With the recent advances elucidating the drug-efflux and energetics of the tripartite assemblies, the understanding of the interaction between the OMFs and PAPs is the last piece remaining in the complete structure of the tripartite pump assembly puzzle.

  11. The periplasmic protein TolB as a potential drug target in Pseudomonas aeruginosa.

    Directory of Open Access Journals (Sweden)

    Alessandra Lo Sciuto

    Full Text Available The Gram-negative bacterium Pseudomonas aeruginosa is one of the most dreaded pathogens in the hospital setting, and represents a prototype of multi-drug resistant "superbug" for which effective therapeutic options are very limited. The identification and characterization of new cellular functions that are essential for P. aeruginosa viability and/or virulence could drive the development of anti-Pseudomonas compounds with novel mechanisms of action. In this study we investigated whether TolB, the periplasmic component of the Tol-Pal trans-envelope protein complex of Gram-negative bacteria, represents a potential drug target in P. aeruginosa. By combining conditional mutagenesis with the analysis of specific pathogenicity-related phenotypes, we demonstrated that TolB is essential for P. aeruginosa growth, both in laboratory and clinical strains, and that TolB-depleted P. aeruginosa cells are strongly defective in cell-envelope integrity, resistance to human serum and several antibiotics, as well as in the ability to cause infection and persist in an insect model of P. aeruginosa infection. The essentiality of TolB for P. aeruginosa growth, resistance and pathogenicity highlights the potential of TolB as a novel molecular target for anti-P. aeruginosa drug discovery.

  12. The periplasmic enzyme, AnsB, of Shigella flexneri modulates bacterial adherence to host epithelial cells.

    Directory of Open Access Journals (Sweden)

    Divya T George

    Full Text Available S. flexneri strains, most frequently linked with endemic outbreaks of shigellosis, invade the colonic and rectal epithelium of their host and cause severe tissue damage. Here we have attempted to elucidate the contribution of the periplasmic enzyme, L-asparaginase (AnsB to the pathogenesis of S. flexneri. Using a reverse genetic approach we found that ansB mutants showed reduced adherence to epithelial cells in vitro and attenuation in two in vivo models of shigellosis, the Caenorhabditis elegans and the murine pulmonary model. To investigate how AnsB affects bacterial adherence, we compared the proteomes of the ansB mutant with its wild type parental strain using two dimensional differential in-gel electrophoresis and identified the outer membrane protein, OmpA as up-regulated in ansB mutant cells. Bacterial OmpA, is a prominent outer membrane protein whose activity has been found to be required for bacterial pathogenesis. Overexpression of OmpA in wild type S. flexneri serotype 3b resulted in decreasing the adherence of this virulent strain, suggesting that the up-regulation of OmpA in ansB mutants contributes to the reduced adherence of this mutant strain. The data presented here is the first report that links the metabolic enzyme AnsB to S. flexneri pathogenesis.

  13. C5 Extract Induces Apoptosis in B16F10 Murine Melanoma Cells ...

    African Journals Online (AJOL)

    cancer activities of C5 extract (C5E), a new herbal preparation from ..... Figure 1: Composition of C5E was analyzed by GC-MS. Among the volatile compounds in C5E, .... body systems because dysfunction of apoptotic signaling could cause serious ...

  14. The C5a/C5aR1 axis controls the development of experimental allergic asthma independent of LysM-expressing pulmonary immune cells.

    Directory of Open Access Journals (Sweden)

    Anna V Wiese

    Full Text Available C5a regulates the development of maladaptive immune responses in allergic asthma mainly through the activation of C5a receptor 1 (C5aR1. Yet, the cell types and the mechanisms underlying this regulation are ill-defined. Recently, we described increased C5aR1 expression in lung tissue eosinophils but decreased expression in airway and pulmonary macrophages as well as in pulmonary CD11b+ conventional dendritic cells (cDCs and monocyte-derived DCs (moDCs during the allergic effector phase using a floxed green fluorescent protein (GFP-C5aR1 knock-in mouse. Here, we determined the role of C5aR1 signaling in neutrophils, moDCs and macrophages for the pulmonary recruitment of such cells and the importance of C5aR1-mediated activation of LysM-expressing cells for the development of allergic asthma. We used LysM-C5aR1 KO mice with a specific deletion of C5aR1 in LysMCre-expressing cells and confirmed the specific deletion of C5aR1 in neutrophils, macrophages and moDCs in the airways and/or the lung tissue. We found that alveolar macrophage numbers were significantly increased in LysM-C5aR1 KO mice. Induction of ovalbumin (OVA-driven experimental allergic asthma in GFP-C5aR1fl/fl and LysM-C5aR1 KO mice resulted in strong but similar airway resistance, mucus production and Th2/Th17 cytokine production. In contrast, the number of airway but not of pulmonary neutrophils was lower in LysM-C5aR1 KO as compared with GFP-C5aR1fl/fl mice. The recruitment of macrophages, cDCs, moDCs, T cells and type 2 innate lymphoid cells was not altered in LysM-C5aR1 KO mice. Our findings demonstrate that C5aR1 is critical for steady state control of alveolar macrophage numbers and the transition of neutrophils from the lung into the airways in OVA-driven allergic asthma. However, C5aR1 activation of LysM-expressing cells plays a surprisingly minor role in the recruitment and activation of such cells and the development of the allergic phenotype in OVA-driven experimental

  15. Prediction of compatibility of crude oils with condensate (C5+); Previsao de compatibilidade de petroleos e condensado (C5+)

    Energy Technology Data Exchange (ETDEWEB)

    Zilio, Evaldo Lopez; Santos, Maria de Fatima Pereira dos [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil); Ramos, Antonio Carlos da Silva; Rolemberg, Marlus Pinheiro [Universidade Federal do Maranhao (UFMA), Sao Luis, MA (Brazil)

    2008-07-01

    Due to the recent raise of the national natural gas demand and to the need of flowing the condensates (C5+) produced from the NGPP (Natural Gas Processing Plant) by adding them to the streams of the crude oil, there was the need to carry out the compatibility prediction of one condensate with two onshore crude oils from Espirito Santo. The model to predict the compatibility among crude oils and among crude oils and oil products is based on the use of the solubility parameter of the oils. To apply it, the solubility parameter of each crude oil or oil product is measured and the parameter of their blend is calculated. If this value is beneath the asphaltenes flocculation parameter, the blend is incompatible; if it is above, the blend is compatible. In this article, the compatibility predictions were done according to the Solubility Parameter Model to two blends: the condensate C with the crude oil X and with the crude oil Y. The model predictions are that both blends are incompatible at given proportions. To check the predictions, the same two blends were experimentally carried out. It must be emphasized that the compatibility tests were done at atmospheric pressure and at the temperature of 15 deg C. These tests consist in adding the condensate to the crude oil with a titrater and visualizing the asphaltenes precipitation at an optical microscope. The experimental results were equivalent to the values predicted by the model. It is worth mentioning that there were several practical difficulties, as the high volatility of the condensate and the fact that the temperatures to determine the parameters and to carry out the tests were very lower than the operation temperature. Therefore, a security factor was applied on the predictions (less 20%). (author)

  16. Cold adaptation of the mononuclear molybdoenzyme periplasmic nitrate reductase from the Antarctic bacterium Shewanella gelidimarina

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, Philippa J.L. [School of Chemistry, University of Sydney, New South Wales 2006 (Australia); Codd, Rachel, E-mail: rachel.codd@sydney.edu.au [School of Chemistry, University of Sydney, New South Wales 2006 (Australia); School of Medical Sciences (Pharmacology) and Bosch Institute, University of New South Wales, New South Wales 2006 (Australia)

    2011-11-04

    Highlights: Black-Right-Pointing-Pointer Cold-adapted phenotype of NapA from the Antarctic bacterium Shewanella gelidimarina. Black-Right-Pointing-Pointer Protein homology model of NapA from S. gelidimarina and mesophilic homologue. Black-Right-Pointing-Pointer Six amino acid residues identified as lead candidates governing NapA cold adaptation. Black-Right-Pointing-Pointer Molecular-level understanding of designing cool-temperature in situ oxyanion sensors. -- Abstract: The reduction of nitrate to nitrite is catalysed in bacteria by periplasmic nitrate reductase (Nap) which describes a system of variable protein subunits encoded by the nap operon. Nitrate reduction occurs in the NapA subunit, which contains a bis-molybdopterin guanine dinucleotide (Mo-MGD) cofactor and one [4Fe-4S] iron-sulfur cluster. The activity of periplasmic nitrate reductase (Nap) isolated as native protein from the cold-adapted (psychrophilic) Antarctic bacterium Shewanella gelidimarina (Nap{sub Sgel}) and middle-temperature adapted (mesophilic) Shewanella putrefaciens (Nap{sub Sput}) was examined at varied temperature. Irreversible deactivation of Nap{sub Sgel} and Nap{sub Sput} occurred at 54.5 and 65 Degree-Sign C, respectively. When Nap{sub Sgel} was preincubated at 21-70 Degree-Sign C for 30 min, the room-temperature nitrate reductase activity was maximal and invariant between 21 and 54 Degree-Sign C, which suggested that Nap{sub Sgel} was poised for optimal catalysis at modest temperatures and, unlike Nap{sub Sput}, did not benefit from thermally-induced refolding. At 20 Degree-Sign C, Nap{sub Sgel} reduced selenate at 16% of the rate of nitrate reduction. Nap{sub Sput} did not reduce selenate. Sequence alignment showed 46 amino acid residue substitutions in Nap{sub Sgel} that were conserved in NapA from mesophilic Shewanella, Rhodobacter and Escherichia species and could be associated with the Nap{sub Sgel} cold-adapted phenotype. Protein homology modeling of Nap{sub Sgel} using a

  17. Extracellular histones are essential effectors of C5aR- and C5L2-mediated tissue damage and inflammation in acute lung injury.

    Science.gov (United States)

    Bosmann, Markus; Grailer, Jamison J; Ruemmler, Robert; Russkamp, Norman F; Zetoune, Firas S; Sarma, J Vidya; Standiford, Theodore J; Ward, Peter A

    2013-12-01

    We investigated how complement activation promotes tissue injury and organ dysfunction during acute inflammation. Three models of acute lung injury (ALI) induced by LPS, IgG immune complexes, or C5a were used in C57BL/6 mice, all models requiring availability of both C5a receptors (C5aR and C5L2) for full development of ALI. Ligation of C5aR and C5L2 with C5a triggered the appearance of histones (H3 and H4) in bronchoalveolar lavage fluid (BALF). BALF from humans with ALI contained H4 histone. Histones were absent in control BALF from healthy volunteers. In mice with ALI, in vivo neutralization of H4 with IgG antibody reduced the intensity of ALI. Neutrophil depletion in mice with ALI markedly reduced H4 presence in BALF and was highly protective. The direct lung damaging effects of extracellular histones were demonstrated by airway administration of histones into mice and rats (Sprague-Dawley), which resulted in ALI that was C5a receptor-independent, and associated with intense inflammation, PMN accumulation, damage/destruction of alveolar epithelial cells, together with release into lung of cytokines/chemokines. High-resolution magnetic resonance imaging demonstrated lung damage, edema and consolidation in histone-injured lungs. These studies confirm the destructive C5a-dependent effects in lung linked to appearance of extracellular histones.

  18. TupA: A Tungstate Binding Protein in the Periplasm of Desulfovibrio alaskensis G20

    Directory of Open Access Journals (Sweden)

    Ana Rita Otrelo-Cardoso

    2014-07-01

    Full Text Available The TupABC system is involved in the cellular uptake of tungsten and belongs to the ABC (ATP binding cassette-type transporter systems. The TupA component is a periplasmic protein that binds tungstate anions, which are then transported through the membrane by the TupB component using ATP hydrolysis as the energy source (the reaction catalyzed by the ModC component. We report the heterologous expression, purification, determination of affinity binding constants and crystallization of the Desulfovibrio alaskensis G20 TupA. The tupA gene (locus tag Dde_0234 was cloned in the pET46 Enterokinase/Ligation-Independent Cloning (LIC expression vector, and the construct was used to transform BL21 (DE3 cells. TupA expression and purification were optimized to a final yield of 10 mg of soluble pure protein per liter of culture medium. Native polyacrylamide gel electrophoresis was carried out showing that TupA binds both tungstate and molybdate ions and has no significant interaction with sulfate, phosphate or perchlorate. Quantitative analysis of metal binding by isothermal titration calorimetry was in agreement with these results, but in addition, shows that TupA has higher affinity to tungstate than molybdate. The protein crystallizes in the presence of 30% (w/v polyethylene glycol 3350 using the hanging-drop vapor diffusion method. The crystals diffract X-rays beyond 1.4 Å resolution and belong to the P21 space group, with cell parameters a = 52.25 Å, b = 42.50 Å, c = 54.71 Å, β = 95.43°. A molecular replacement solution was found, and the structure is currently under refinement.

  19. Catalytic Mechanism and Mode of Action of the Periplasmic Alginate Epimerase AlgG

    NARCIS (Netherlands)

    Wolfram, Francis; Kitova, Elena N.; Robinson, Howard; Walvoort, Marthe T. C.; Codee, Jeroen D. C.; Klassen, John S.; Howell, P. Lynne

    2014-01-01

    Background: The alginate epimerase AlgG converts mannuronate to its C5 epimer guluronate at the polymer level. Results: The structure of Pseudomonas syringae AlgG has been determined, and the protein has been functionally characterized. Conclusion: His(319) acts as the catalytic base, whereas

  20. Differences in substrate specificity of C(5)-substituted or C(5)-unsubstituted pyrimidine nucleotides by DNA polymerases from thermophilic bacteria, archaea, and phages.

    Science.gov (United States)

    Sawai, Hiroaki; Nagashima, Junichi; Kuwahara, Msayasu; Kitagata, Rina; Tamura, Takehiro; Matsui, Ikuo

    2007-09-01

    The pyrimidine bases of RNA are uracil (U) and cytosine (C), while thymine (T) and C are used for DNA. The C(5) position of C and U is unsubstituted, whereas the C(5) of T is substituted with a Me group. Miller et al. hypothesized that various C(5)-substituted uracil derivatives were formed during chemical evolution, and that C(5)-substituted U derivatives may have played important roles in the transition from an 'RNA world' to a 'DNA-RNA-protein world'. Hyperthermophilic bacteria and archaea are considered to be primitive organisms that are evolutionarily close to the universal ancestor of all life on earth. Thus, we examined the substrate specificity of several C(5)-substituted or C(5)-unsubstituted dUTP and dCTP analogs for several DNA polymerases from hyperthermophilic bacteria, hyperthermophilic archaea, and viruses during PCR or primer extension reaction. The substrate specificity of the C(5)-substituted or C(5)-unsubstituted pyrimidine nucleotides varied greatly depending on the type of DNA polymerase. The significance of this difference in substrate specificity in terms of the origin and evolution of the DNA replication system is discussed briefly.

  1. Complement C5a-C5aR interaction enhances MAPK signaling pathway activities to mediate renal injury in trichloroethylene sensitized BALB/c mice.

    Science.gov (United States)

    Zhang, Jia-xiang; Zha, Wan-sheng; Ye, Liang-ping; Wang, Feng; Wang, Hui; Shen, Tong; Wu, Chang-hao; Zhu, Qi-xing

    2016-02-01

    We have previously shown complement activation as a possible mechanism for trichloroethylene (TCE) sensitization, leading to multi-organ damage including the kidneys. In particular, excessive deposition of C5 and C5b-9-the membrane attack complex, which can generate significant tissue damage, was observed in the kidney tissue after TCE sensitization. The present study tested the hypothesis that anaphylatoxin C5a binding to its receptor C5aR mediates renal injury in TCE-sensitized BALB/c mice. BALB/c mice were sensitized through skin challenge with TCE, with or without pretreatment by the C5aR antagonist W54011. Kidney histopathology and the renal functional test were performed to assess renal injury, and immunohistochemistry and fluorescent labeling were carried out to assess C5a and C5aR expressions. TCE sensitization up-regulated C5a and C5aR expressions in kidney tissue, generated inflammatory infiltration, renal tubule damage, glomerular hypercellularity and impaired renal function. Antagonist pretreatment blocked C5a binding to C5aR and attenuated TCE-induced tissue damage and renal dysfunction. TCE sensitization also caused the deposition of major pro-inflammatory cytokines IL-2, TNF-α and IFN-γ in the kidney tissue (P < 0.05); this was accompanied by increased expression of P-p38, P-ERK and P-JNK proteins (P < 0.05). Pretreatment with the C5aR antagonist attenuated the increase of expression of P-p38, P-ERK and P-JNK proteins (P < 0.05) and also consistently reduced the TCE sensitization-induced increase of IL-2, TNF-α and IFN-γ (P < 0.05). These data identify C5a binding to C5aR, MAP kinase activation, and inflammatory cytokine release as a novel mechanism for complement-mediated renal injury by sensitization with TCE or other environmental chemicals. Copyright © 2015 John Wiley & Sons, Ltd.

  2. Primary complement C5 deficiencies – Molecular characterization and clinical review of two families

    DEFF Research Database (Denmark)

    Schejbel, Lone; Fadnes, Dag; Permin, Henrik

    2013-01-01

    of the Norwegian patient, previously diagnosed as homozygous C5 deficient and suffering four Neisseria infections, an additional case of C5 deficiency was discovered, who had experienced one episode of Neisseria infections. Detailed review of the clinical history of the patients and their healthy relatives did...... infections, which is not covered by the current vaccines. These data support the clinical guidelines for patients treated with C5 inhibitors, who are functional C5 deficient by the treatment....

  3. C5 Extract Induces Apoptosis in B16F10 Murine Melanoma Cells ...

    African Journals Online (AJOL)

    Purpose: To investigate the anti-cancer activities of C5 extract (C5E), a new herbal preparation from Korea, on B16F10 cells. Methods: The anti-proliferative effects of C5E were assessed by culturing B16F10 cells in the presence or absence of C5E. Cell cycle progression was analyzed by PI staining using flow cytometry.

  4. Data of evolutionary structure change: 1C5UA-2OQUA [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available A 2OQUA ence>SLQYRSGSSWAHTCG... A 2OQUA ence>PLHCLVNGQYAVHG.../index> 2OQU A 2OQUA ence>MVCAG-GDGVR...1C5UA-2OQUA 1C5U 2OQU A A IVGGYTCGANTVPYQVSLNSG-----YHFCGGSLINSQW...entryIDChain>1C5UA ence>SLNSG-----YHFCGence> EEE ----- EE

  5. Functional Properties of Mouse Chitotriosidase Expressed in the Periplasmic Space of Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Masahiro Kimura

    Full Text Available Chitotriosidase (Chit1 is an enzyme associated with various diseases, including Gaucher disease, chronic obstructive pulmonary disease, Alzheimer disease and cystic fibrosis. In this study, we first expressed mouse mature Chit1 fused with V5 and (His6 tags at the C-terminus (Chit1-V5-His in the cytoplasm of Escherichia coli and found that most of the expressed protein was insoluble. In contrast, Chit1 tagged with Protein A at the N-terminus and V5-His at the C-terminus, was expressed in the periplasmic space of E. coli as a soluble protein and successfully purified. We evaluated the chitinolytic properties of the recombinant enzyme using 4-nitrophenyl N,N'-diacetyl-β-D-chitobioside [4NP-chitobioside, 4NP-(GlcNAc2] and found that its activity was comparable to CHO cells-expressed Chit1-V5-His. Optimal conditions for the E. coli-produced Chit1 were pH ~5.0 at 50°C. Chit1 was stable after 1 h incubation at pH 5.0~11.0 on ice and its chitinolytic activity was lost at pH 2.0, although the affinity to chitin remained unchanged. Chit1 efficiently cleaved crystalline and colloidal chitin substrates as well as oligomers of N-acetyl-D-glucosamine (GlcNAc releasing primarily (GlcNAc2 fragments at pH 5.0. On the other hand, (GlcNAc3 was relatively resistant to digestion by Chit1. The degradation of 4NP-(GlcNAc2 and (GlcNAc3 was less evident at pH 7.0~8.0, while (GlcNAc2 production from colloidal chitin and (GlcNAc6 at these pH conditions remained strong at the neutral conditions. Our results indicate that Chit1 degrades chitin substrates under physiological conditions and suggest its important pathophysiological roles in vivo.

  6. Improving Fab' fragment retention in an autonucleolytic Escherichia coli strain by swapping periplasmic nuclease translocation signal from OmpA to DsbA.

    Science.gov (United States)

    Schofield, Desmond M; Sirka, Ernestas; Keshavarz-Moore, Eli; Ward, John M; Nesbeth, Darren N

    2017-12-01

    To reduce unwanted Fab' leakage from an autonucleolytic Escherichia coli strain, which co-expresses OmpA-signalled Staphylococcal nuclease and Fab' fragment in the periplasm, by substituting in Serratial nuclease and the DsbA periplasm translocation signal as alternatives. We attempted to genetically fuse a nuclease from Serratia marcescens to the OmpA signal peptide but plasmid construction failed, possibly due to toxicity of the resultant nuclease. Combining Serratial nuclease to the DsbA signal peptide was successful. The strain co-expressing this nuclease and periplasmic Fab' grew in complex media and exhibited nuclease activity detectable by DNAse agar plate but its growth in defined medium was retarded. Fab' coexpression with Staphylococcal nuclease fused to the DsbA signal peptide resulted in cells exhibiting nuclease activity and growth in defined medium. In cultivation to high cell density in a 5 l bioreactor, DsbA-fused Staphylococcal nuclease co-expression coincided with reduced Fab' leakage relative to the original autonucleolytic Fab' strain with OmpA-fused staphylococcal nuclease. We successfully rescued Fab' leakage back to acceptable levels and established a basis for future investigation of the linkage between periplasmic nuclease expression and leakage of co-expressed periplasmic Fab' fragment to the surrounding growth media.

  7. Molecular analysis of human complement component C5: localization of the structural gene to chromosome 9

    International Nuclear Information System (INIS)

    Wetsel, R.A.; Lemons, R.S.; Le Beau, M.M.; Barnum, S.R.; Noack, D.; Tack, B.F.

    1988-01-01

    A human C5 clone (pC5HG2) was isolated from a cDNA library constructed from Hep G2 mRNA. he DNA sequence showed that the pC5HG2 insert was comprised of 3309 base pairs of pro-C5 coding sequence and 404 base pairs of 3'-untranslated sequence. The derived amino acid sequence contained the entire coding sequence of the C5 α-chain, the β-α-chain junction region, and 100 amino acids (approximately 50%) of the β-chain. Protein sequences of four C5 tryptic peptides were aligned exactly to this sequence and demonstrated that C5 synthesized and secreted by Hep G2 cells is probably identical with plasma-derived C5. Coding sequence alignment of the human C5 sequences with those of murine C5 indicated that 80% of the nucleotides and 79% of the amino acids were placed identically in the two species. Amino acid sequence alignment of the homologous family members C3, C4, and α 2 -macroglobulin with that of C5 demonstrated 27%, 25%, and 19% identity, respectively. As was found in murine C5, the corresponding thiol ester region of human C5 contained several conserved amino acids, but the critical cysteine and glutamine residues which give rise to the intramolecular thiol ester bond in C3, C4, and α 2 -macroglobulin were absent in C5, having been replaced by serine and alanine, respectively. With the use of a panel of hamster-human somatic cell hybrids, the C5 gene was mapped to human chromosome 9. In situ chromosomal hybridization studies employing metaphase cells further localized the gene to bands 9q32-34, with the largest cluster of grains at 9q34.1

  8. Deficiency of C5L2 increases macrophage infiltration and alters adipose tissue function in mice.

    Directory of Open Access Journals (Sweden)

    Danny Gauvreau

    Full Text Available BACKGROUND: Obesity is considered as a systemic chronic low grade inflammation characterized by increased serum pro-inflammatory proteins and accumulation of macrophages within white adipose tissue (WAT of obese patients. C5L2, a 7-transmembrane receptor, serves a dual function, binding the lipogenic hormone acylation stimulating protein (ASP, and C5a, involved in innate immunity. AIM: We evaluated the impact of C5L2 on macrophage infiltration in WAT of wildtype (Ctl and C5L2 knock-out (C5L2(-/- mice over 6, 12 and 24 weeks on a chow diet and moderate diet-induced obesity (DIO conditions. RESULTS: In Ctl mice, WAT C5L2 and C5a receptor mRNA increased (up to 10-fold both over time and with DIO. By contrast, in C5L2(-/-, there was no change in C5aR in WAT. C5L2(-/- mice displayed higher macrophage content in WAT, varying by time, fat depot and diet, associated with altered systemic and WAT cytokine patterns compared to Ctl mice. However, in all cases, the M1 (pro- vs M2 (anti-inflammatory macrophage proportion was unchanged but C5L2(-/- adipose tissue secretome appeared to be more chemoattractant. Moreover, C5L2(-/- mice have increased food intake, increased WAT, and altered WAT lipid gene expression, which is reflected systemically. Furthermore, C5L2(-/- mice have altered glucose/insulin metabolism, adiponectin and insulin signalling gene expression in WAT, which could contribute to development of insulin resistance. CONCLUSION: Disruption of C5L2 increases macrophage presence in WAT, contributing to obesity-associated pathologies, and further supports a dual role of complement in WAT. Understanding this effect of the complement system pathway could contribute to targeting treatment of obesity and its comorbidities.

  9. Type IX secretion system PorM and gliding machinery GldM form arches spanning the periplasmic space.

    Science.gov (United States)

    Leone, Philippe; Roche, Jennifer; Vincent, Maxence S; Tran, Quang Hieu; Desmyter, Aline; Cascales, Eric; Kellenberger, Christine; Cambillau, Christian; Roussel, Alain

    2018-01-30

    Type IX secretion system (T9SS), exclusively present in the Bacteroidetes phylum, has been studied mainly in Flavobacterium johnsoniae and Porphyromonas gingivalis. Among the 18 genes, essential for T9SS function, a group of four, porK-N (P. gingivalis) or gldK-N (F. johnsoniae) belongs to a co-transcribed operon that expresses the T9SS core membrane complex. The central component of this complex, PorM (or GldM), is anchored in the inner membrane by a trans-membrane helix and interacts through the outer membrane PorK-N complex. There is a complete lack of available atomic structures for any component of T9SS, including the PorKLMN complex. Here we report the crystal structure of the GldM and PorM periplasmic domains. Dimeric GldM and PorM, each contain four domains of ~180-Å length that span most of the periplasmic space. These and previously reported results allow us to propose a model of the T9SS core membrane complex as well as its functional behavior.

  10. Assembly and Regulation of the Membrane Attack Complex Based on Structures of C5b6 and sC5b9

    Directory of Open Access Journals (Sweden)

    Michael A. Hadders

    2012-03-01

    Full Text Available Activation of the complement system results in formation of membrane attack complexes (MACs, pores that disrupt lipid bilayers and lyse bacteria and other pathogens. Here, we present the crystal structure of the first assembly intermediate, C5b6, together with a cryo-electron microscopy reconstruction of a soluble, regulated form of the pore, sC5b9. Cleavage of C5 to C5b results in marked conformational changes, distinct from those observed in the homologous C3-to-C3b transition. C6 captures this conformation, which is preserved in the larger sC5b9 assembly. Together with antibody labeling, these structures reveal that complement components associate through sideways alignment of the central MAC-perforin (MACPF domains, resulting in a C5b6-C7-C8β-C8α-C9 arc. Soluble regulatory proteins below the arc indicate a potential dual mechanism in protection from pore formation. These results provide a structural framework for understanding MAC pore formation and regulation, processes important for fighting infections and preventing complement-mediated tissue damage.

  11. C5a receptor deficiency alters energy utilization and fat storage.

    Directory of Open Access Journals (Sweden)

    Christian Roy

    Full Text Available To investigate the impact of whole body C5a receptor (C5aR deficiency on energy metabolism and fat storage.Male wildtype (WT and C5aR knockout (C5aRKO mice were fed a low fat (CHOW or a high fat high sucrose diet-induced obesity (DIO diet for 14 weeks. Body weight and food intake were measured weekly. Indirect calorimetry, dietary fatload clearance, insulin and glucose tolerance tests were also evaluated. Liver, muscle and adipose tissue mRNA gene expression were measured by RT-PCR.At week one and 12, C5aRKO mice on DIO had increased oxygen consumption. After 12 weeks, although food intake was comparable, C5aRKO mice had lower body weight (-7% CHOW, -12% DIO as well as smaller gonadal (-38% CHOW, -36% DIO and inguinal (-29% CHOW, -30% DIO fat pads than their WT counterparts. Conversely, in WT mice, C5aR was upregulated in DIO vs CHOW diets in gonadal adipose tissue, muscle and liver, while C5L2 mRNA expression was lower in C5aRKO on both diet. Furthermore, blood analysis showed lower plasma triglyceride and non-esterified fatty acid levels in both C5aRKO groups, with faster postprandial triglyceride clearance after a fatload. Additionally, C5aRKO mice showed lower CD36 expression in gonadal and muscle on both diets, while DGAT1 expression was higher in gonadal (CHOW and liver (CHOW and DIO and PPARγ was increased in muscle and liver.These observations point towards a role (either direct or indirect for C5aR in energy expenditure and fat storage, suggesting a dual role for C5aR in metabolism as well as in immunity.

  12. The periplasmic membrane proximal domain of MacA acts as a switch in stimulation of ATP hydrolysis by MacB transporter

    OpenAIRE

    Modali, Sita D.; Zgurskaya, Helen I.

    2011-01-01

    Escherichia coli MacAB-TolC is a tri-partite macrolide efflux transporter driven by hydrolysis of ATP. In this complex, MacA is the periplasmic membrane fusion protein that stimulates the activity of MacB transporter and establishes the link with the outer membrane channel TolC. The molecular mechanism by which MacA stimulates MacB remains unknown. Here, we report that the periplasmic membrane proximal domain of MacA plays a critical role in functional MacA-MacB interactions and stimulation o...

  13. Complement C5a receptor antagonism by protamine and poly-L-Arg on human leukocytes.

    Science.gov (United States)

    Olsen, U B; Selmer, J; Kahl, J U

    1988-01-01

    It is shown that protamine selectively and dose-dependently inhibits complement C5a-induced leukocyte responses such as histamine release from basophils, chemiluminescence and beta-glucuronidase release from neutrophils. Protamine produces parallel rightward displacements of the C5a dose-response curves. The inhibitory capacity of the polypeptide is reversible and disappears following repeated washing of exposed cells. In neutrophils poly-L-Arg similarly and specifically antagonizes C5a-induced chemiluminescence and enzyme release. This polymer alone, however, degranulates basophils and neutrophils, leading to histamine and enzyme release, respectively. It is concluded that on human neutrophils the arginine-rich polycations protamine and poly-L-Arg exhibit a competitive C5a receptor antagonism. In addition, protamine inhibits the C5a receptors on basophils. It is hypothesized that molecular conformations of the arginine-rich polycations might bind reversibly to, and block negatively charged groups at the C5a-receptor sites.

  14. Substrate recognition by complement convertases revealed in the C5-cobra venom factor complex

    DEFF Research Database (Denmark)

    Laursen, Nick Stub; Andersen, Kasper Røjkjær; Braren, Ingke

    2011-01-01

    with a protease subunit (Bb or C2a). We determined the crystal structures of the C3b homologue cobra venom factor (CVF) in complex with C5, and in complex with C5 and the inhibitor SSL7 at 4.3 Å resolution. The structures reveal a parallel two-point attachment between C5 and CVF, where the presence of SSL7 only...... slightly affects the C5-CVF interface, explaining the IgA dependence for SSL7-mediated inhibition of C5 cleavage. CVF functions as a relatively rigid binding scaffold inducing a conformational change in C5, which positions its cleavage site in proximity to the serine protease Bb. A general model...

  15. Radioimmunoelectrophoresis, a sensitive method for detecting cleavage of the fifth component of human complement (C5)

    International Nuclear Information System (INIS)

    Perez, H.D.; Ong, R.; Banda, D.; Goldstein, I.M.

    1983-01-01

    A method has been developed for detecting cleavage of human C5 in serum and whole blood as a consequence of complement activation. Standard, single-dimension immunoelectrophoresis was performed using as antibody a radioiodinated IgG fraction prepared from a commercially available antiserum to human C5. Autoradiographs developed after radioimmunoelectrophoresis of either normal human serum or functionally pure human C5 revealed only one precipitin band. In contrast, when either zymosan-treated serum or trypsin-treated human C5 were examined with this technique, two additional precipitin bands were detected. One migrated more anodally than native C5 while the other remained at the origin (cathode). Radioimmunoelectrophoresis was significantly more sensitive as an indicator of complement activation in human serum than either measurements of total hemolytic complement or a standard assay for complement (C5)-derived chemotactic activity. (Auth.)

  16. Substrate recognition by complement convertases revealed in the C5-cobra venom factor complex

    DEFF Research Database (Denmark)

    Laursen, Nick Stub; Andersen, Kasper Røjkjær; Braren, Ingke

    2011-01-01

    with a protease subunit (Bb or C2a). We determined the crystal structures of the C3b homologue cobra venom factor (CVF) in complex with C5, and in complex with C5 and the inhibitor SSL7 at 4.3 Å resolution. The structures reveal a parallel two-point attachment between C5 and CVF, where the presence of SSL7 only...

  17. Adjacent-Vertex-Distinguishing Total Chromatic Numbers of C5 ∨ Kt%图C5∨Kt的邻点可区别全色数

    Institute of Scientific and Technical Information of China (English)

    张芳红; 王治文; 陈祥恩

    2012-01-01

    设f是图G的一个正常全染色.对任意x∈V(G),令C(x)表示与点x相关联的边的颜色以及点x的颜色所构成的集合.若对任意uv∈E(G),有C(u)≠C(v),则称f是图G的一个邻点可区别全染色.对一个图G进行邻点可区别全染色所需的最少的颜色的数目称为G的邻点可区别全色数,记为xat(G).用C5∨Kt表示长为5的圈与t阶完全图的联图.讨论了c5∨Kt的邻点可区别全色数.利用正多边形的对称性构造染色以及组合分析的方法,得到了当t是大于等于3的奇数以及t是偶数且2≤t≤22时,xat(C5∨Kt)=t+6,当t是偶数且t≥24时,Xat(C5∨Kt)=t+7.%Let / be a proper total coloring of G. For each x ∈V(G),let C(x) denote the set of all colors of the edhes incident with x and the color of x. If (V) uv ∈E(G),we have C(u) ≠ C(v),then / is called an adjacent vertex distinguishing total coloring of G. The minimum number k for which there exists an adjacent vertex distinguishing total coloring of G using k colors is called the adjacent vertex distinguishing total chromatic number of G and denoted by Xat(G). Let C5 V Kt be the join of the cycle C5 of order 5 and the complete graph Kt of order t. In this paper,we discuss adjacent-vertex-distinguishing total chromatic numbers of C5 V Kt. By using symmetry of regular polygons to construct coloring,and methods of combinatorial analysis,we obtained that for t is odd with t ≥ 3 or t is even with 2 ≤ t ≤ 22,we have Xat(C5,V Kt) = t + 6; for t is even with t ≥ 24,we have Xat(C5 V Kt) = t + 7.

  18. Experimental Malaria in Pregnancy Induces Neurocognitive Injury in Uninfected Offspring via a C5a-C5a Receptor Dependent Pathway.

    Directory of Open Access Journals (Sweden)

    Chloë R McDonald

    2015-09-01

    Full Text Available The in utero environment profoundly impacts childhood neurodevelopment and behaviour. A substantial proportion of pregnancies in Africa are at risk of malaria in pregnancy (MIP however the impact of in utero exposure to MIP on fetal neurodevelopment is unknown. Complement activation, in particular C5a, may contribute to neuropathology and adverse outcomes during MIP. We used an experimental model of MIP and standardized neurocognitive testing, MRI, micro-CT and HPLC analysis of neurotransmitter levels, to test the hypothesis that in utero exposure to malaria alters neurodevelopment through a C5a-C5aR dependent pathway. We show that malaria-exposed offspring have persistent neurocognitive deficits in memory and affective-like behaviour compared to unexposed controls. These deficits were associated with reduced regional brain levels of major biogenic amines and BDNF that were rescued by disruption of C5a-C5aR signaling using genetic and functional approaches. Our results demonstrate that experimental MIP induces neurocognitive deficits in offspring and suggest novel targets for intervention.

  19. C5a receptor (CD88) blockade protects against MPO-ANCA GN.

    Science.gov (United States)

    Xiao, Hong; Dairaghi, Daniel J; Powers, Jay P; Ertl, Linda S; Baumgart, Trageen; Wang, Yu; Seitz, Lisa C; Penfold, Mark E T; Gan, Lin; Hu, Peiqi; Lu, Bao; Gerard, Norma P; Gerard, Craig; Schall, Thomas J; Jaen, Juan C; Falk, Ronald J; Jennette, J Charles

    2014-02-01

    Necrotizing and crescentic GN (NCGN) with a paucity of glomerular immunoglobulin deposits is associated with ANCA. The most common ANCA target antigens are myeloperoxidase (MPO) and proteinase 3. In a manner that requires activation of the alternative complement pathway, passive transfer of antibodies to mouse MPO (anti-MPO) induces a mouse model of ANCA NCGN that closely mimics human disease. Here, we confirm the importance of C5aR/CD88 in the mediation of anti-MPO-induced NCGN and report that C6 is not required. We further demonstrate that deficiency of C5a-like receptor (C5L2) has the reverse effect of C5aR/CD88 deficiency and results in more severe disease, indicating that C5aR/CD88 engagement enhances inflammation and C5L2 engagement suppresses inflammation. Oral administration of CCX168, a small molecule antagonist of human C5aR/CD88, ameliorated anti-MPO-induced NCGN in mice expressing human C5aR/CD88. These observations suggest that blockade of C5aR/CD88 might have therapeutic benefit in patients with ANCA-associated vasculitis and GN.

  20. The complement anaphylatoxin C5a receptor contributes to obese adipose tissue inflammation and insulin resistance.

    Science.gov (United States)

    Phieler, Julia; Chung, Kyoung-Jin; Chatzigeorgiou, Antonios; Klotzsche-von Ameln, Anne; Garcia-Martin, Ruben; Sprott, David; Moisidou, Maria; Tzanavari, Theodora; Ludwig, Barbara; Baraban, Elena; Ehrhart-Bornstein, Monika; Bornstein, Stefan R; Mziaut, Hassan; Solimena, Michele; Karalis, Katia P; Economopoulou, Matina; Lambris, John D; Chavakis, Triantafyllos

    2013-10-15

    Obese adipose tissue (AT) inflammation contributes critically to development of insulin resistance. The complement anaphylatoxin C5a receptor (C5aR) has been implicated in inflammatory processes and as regulator of macrophage activation and polarization. However, the role of C5aR in obesity and AT inflammation has not been addressed. We engaged the model of diet-induced obesity and found that expression of C5aR was significantly upregulated in the obese AT, compared with lean AT. In addition, C5a was present in obese AT in the proximity of macrophage-rich crownlike structures. C5aR-sufficient and -deficient mice were fed a high-fat diet (HFD) or a normal diet (ND). C5aR deficiency was associated with increased AT weight upon ND feeding in males, but not in females, and with increased adipocyte size upon ND and HFD conditions in males. However, obese C5aR(-/-) mice displayed improved systemic and AT insulin sensitivity. Improved AT insulin sensitivity in C5aR(-/-) mice was associated with reduced accumulation of total and proinflammatory M1 macrophages in the obese AT, increased expression of IL-10, and decreased AT fibrosis. In contrast, no difference in β cell mass was observed owing to C5aR deficiency under an HFD. These results suggest that C5aR contributes to macrophage accumulation and M1 polarization in the obese AT and thereby to AT dysfunction and development of AT insulin resistance.

  1. The (gas + liquid) critical properties and phase behaviour of some binary alkanol (C2-C5) + alkane (C5-C12) mixtures

    International Nuclear Information System (INIS)

    Morton, David W.; Lui, Matthew P.W.; Young, Colin L.

    2003-01-01

    Previously, the investigation of the (gas + liquid) critical properties of (alkanol + alkane) mixtures has focussed on (primary alkanol + straight chain alkane) mixtures. The experimental data available for (alkanol + alkane) mixtures, which include secondary or tertiary alcohols and/or branched chain alkanes, are extremely limited. This work extends the existing body of data on (alkanol + alkane) mixtures to include mixtures containing these components. Here the (gas + liquid) critical temperatures of 29 {alkanol (C 2 -C 5 ) + alkane (C 5 -C 12 )} mixtures are reported. All the (gas + liquid) critical lines for the binary mixtures studied are continuous, indicating they obey either Type I or Type II phase behaviour

  2. Critical role for complement receptor C5aR2 in the pathogenesis of renal ischemia-reperfusion injury

    NARCIS (Netherlands)

    Poppelaars, Felix; van Werkhoven, Maaike B; Kotimaa, Juha; Veldhuis, Zwanida J; Ausema, Albertina; Broeren, Stefan G M; Damman, Jeffrey; Hempel, Julia C.; Leuvenink, Henri G D; Daha, Mohamed R; van Son, Willem J; van Kooten, Cees; van Os, Ronald P; Hillebrands, Jan-Luuk; Seelen, Marc A

    The complement system, and specifically C5a, is involved in renal ischemia-reperfusion (IR) injury. The 2 receptors for complement anaphylatoxin C5a (C5aR1 and C5aR2) are expressed on leukocytes as well as on renal epithelium. Extensive evidence shows that C5aR1 inhibition protects kidneys from IR

  3. Nano-jewellery: C5Au12--a gold-plated diamond at molecular level.

    Science.gov (United States)

    Naumkin, F

    2006-06-07

    A mixed carbon-metal cluster is designed by combining the tetrahedral C(5) radical (with a central atom-the skeleton of the C(5)H(12) molecule) and the spherical Au(12) layer (the external atomic shell of the Au(13) cluster). The C(5)Au(12) cluster and its negative and positive ionic derivatives, C(5)Au(12)(+/-), are investigated ab initio (DFT) in terms of optimized structures and relative energies of a few spin-states, for the icosahedral-like and octahedral-like isomers. The cluster is predicted to be generally more stable in its octahedral shape (similar to C(5)H(12)) which prevails for the negative ion and may compete with the icosahedral shape for the neutral system and positive ion. Adiabatic ionization energies (AIE) and electron affinities (AEA) of C(5)Au(12), vertical electron-detachment (VDE) energies of C(5)Au(12)(-), and vertical ionization and electron-attachment energies (VIE, VEA) of C(5)Au(12) are calculated as well, and compared with those for the corresponding isomers of the Au(13) cluster. The AIE and VIE values are found to be close for the two systems, while the AEA and VDE values are significantly reduced for the radical-based species. A simple fragment-based model is proposed for the decomposition of the total interaction into carbon-gold and gold-gold components.

  4. C5a binding to human polymorphonuclear leukocyte plasma membrane (PMNLM) receptors

    International Nuclear Information System (INIS)

    Conway, R.G.; Mollison, K.W.; Carter, G.W.; Lane, B.

    1986-01-01

    Previous investigations of the C5a receptor have been performed using intact human PMNL. To circumvent some of the potential problems with such whole cell assays (e.g. internalization or metabolism of radioligand) the authors have developed a PMNLM binding assay. Human PMNLM were prepared by nitrogen cavitation and Percoll gradient centrifugation. Specific binding of [ 125 I]C5a to PMNLM was: high affinity, K/sub D/ = 0.6 nM; saturable, B/sub max/ = 8.7 pmol/mg protein; and reversible. Kinetic measurements agree with the K/sub D/ value obtained by Scatchard analysis. Furthermore, the binding activity of C5a correlates with biological activity as measured by myeloperoxidase release from human PMNL. Human serum C5a and recombinant C5a bind with similar affinities when measured by competition or direct binding and label the same number of sites in human PMNLM. The nonhydrolyzable GTP analog, GppNHp, induces a low affinity state of the C5a receptor (4-6 fold shift in K/sub D/) with little effect on B/sub max/. In summary, the criteria have been satisfied for identification of a biologically relevant C5a binding site in human PMNLM. Regulation of the C5a receptor and its membrane transduction mechanism(s) appears to involve guanyl nucleotides, as has been found for other chemoattractant receptors

  5. MzrA-EnvZ Interactions in the Periplasm Influence the EnvZ/OmpR Two-Component Regulon▿ †

    Science.gov (United States)

    Gerken, Henri; Misra, Rajeev

    2010-01-01

    MzrA was identified as a modulator of the EnvZ/OmpR two-component signal transduction system. Previous evidence indicated that MzrA interacts with EnvZ and modulates its enzymatic activities to influence OmpR phosphate (OmpR∼P) levels. Moreover, MzrA was shown to connect the bacterial envelope stress response systems CpxA/CpxR and σE to EnvZ/OmpR to widen the defensive response regulatory network. In this study, experiments were carried out to establish whether the membrane or periplasmic domain of MzrA is critical for MzrA-EnvZ interactions and to reveal MzrA residues that play an important role in these interactions. Data obtained from chimeric constructs, in which the transmembrane domain of MzrA was replaced with the unrelated transmembrane domain of NarX or signal sequence of PhoA, showed that the transmembrane domain residues of MzrA do not play a critical role in MzrA-EnvZ interactions. The importance of the periplasmic domain of MzrA in MzrA-EnvZ interactions was revealed by characterizing bifunctional, fully soluble, and periplasmically localized MalE::MzrA chimeras. This was further corroborated through the isolation of loss-of-function, single-amino-acid substitutions in the conserved periplasmic domain of MzrA that interfered with MzrA-EnvZ binding in a bacterial two-hybrid system. Together, the data suggest that the binding of MzrA to EnvZ influences the ability of EnvZ to receive and/or respond to environmental signals in the periplasm and modulate its biochemical output to OmpR. PMID:20889743

  6. NMR and TRLFS studies of Ln(iii) and An(iii) C5-BPP complexes.

    Science.gov (United States)

    Adam, Christian; Beele, Björn B; Geist, Andreas; Müllich, Udo; Kaden, Peter; Panak, Petra J

    2015-02-01

    C5-BPP is a highly efficient N-donor ligand for the separation of trivalent actinides, An(iii), from trivalent lanthanides, Ln(iii). The molecular origin of the selectivity of C5-BPP and many other N-donor ligands of the BTP-type is still not entirely understood. We present here the first NMR studies on C5-BPP Ln(iii) and An(iii) complexes. C5-BPP is synthesized with 10% 15 N labeling and characterized by NMR and LIFDI-MS methods. 15 N NMR spectroscopy gives a detailed insight into the bonding of C5-BPP with lanthanides and Am(iii) as a representative for trivalent actinide cations, revealing significant differences in 15 N chemical shift for coordinating nitrogen atoms compared to Ln(iii) complexes. The temperature dependence of NMR chemical shifts observed for the Am(iii) complex indicates a weak paramagnetism. This as well as the observed large chemical shift for coordinating nitrogen atoms show that metal-ligand bonding in Am(C5-BPP) 3 has a larger share of covalence than in lanthanide complexes, confirming earlier studies. The Am(C5-BPP) 3 NMR sample is furthermore spiked with Cm(iii) and characterized by time-resolved laser fluorescence spectroscopy (TRLFS), yielding important information on the speciation of trace amounts of minor complex species.

  7. CLONING, PURIFICATION AND CHARACTERIZATION OF HALOTOLERANT XYLANASE FROM Geobacillus Thermodenitrificans C5

    Directory of Open Access Journals (Sweden)

    Muhammad Irfan

    2016-06-01

    Full Text Available High levels of extracellular xylanase activity (994.50 IU/ml produced by Geobacillus thermodenitrificans C5 originated gene was detected when it was expressed in E. coli BL21 host. Thermostable xylanase (GthC5Xyl was purified to homogeneity and showed a molecular mass of approximately 44 kDa according to SDS-PAGE. The specific activity of the purified GthC5Xyl was up to 1243.125IU/mg with a 9.89-fold purification. The activity of GthC5Xyl was stimulated by CoCl2, MnSO4, CuSO4, MnCl2 but was inhibited by FeSO4, Hg, CaSO4. GthC5Xyl showed resistant to SDS, Tween 20, Triton X-100, β- Mercaptoethanol, PMSF, DTT, NEM and DEPC, SDS, and EDTA. A greater affinity for oat spelt xylan was exhibited by GthC5Xyl with maximum enzymatic activity at 60°C and 6.0 pH. The activity portrayed by GthC5Xyl was found to be acellulytic with stability at high temperature (70°C-80°C and low pH (4.0 to 8.0. Xylobiose and xylopentose were the end products of proficient oat spelt xylanase hydrolysis by GthC5Xyl. High SDS resistance and broader stability of GthC5Xyl proves it to be worthy of impending application in numerous industrial processes especially textile, detergents and animal feed industry.

  8. Estrogen enhances expression of the complement C5a receptor and the C5a-agonist evoked calcium influx in hormone secreting neurons of the hypothalamus.

    Science.gov (United States)

    Farkas, Imre; Varju, Patricia; Szabo, Emese; Hrabovszky, Erik; Okada, Noriko; Okada, Hidechika; Liposits, Zsolt

    2008-01-01

    In the present study we examined presence of the complement C5a receptor (C5aR) in hypothalamic neurosecretory neurons of the rodent brain and effect of estrogen on C5aR expression. Whole cell patch clamp measurements revealed that magnocellular neurons in the supraoptic and paraventricular nuclei of hypothalamic slices of the rats responded to the C5aR-agonist PL37-MAP peptide with calcium ion current pulses. Gonadotropin-releasing hormone (GnRH) producing neurons in slices of the preoptic area of the mice also reacted to the peptide treatment with inward calcium current. PL37-MAP was able to evoke the inward ion current of GnRH neurons in slices from ovariectomized animals. The amplitude of the inward pulses became higher in slices obtained from 17beta-estradiol (E2) substituted mice. Calcium imaging experiments demonstrated that PL37-MAP increased the intracellular calcium content in the culture of the GnRH-producing GT1-7 cell line in a concentration-dependent manner. Calcium imaging also showed that E2 pretreatment elevated the PL37-MAP evoked increase of the intracellular calcium content in the GT1-7 cells. The estrogen receptor blocker Faslodex in the medium prevented the E2-evoked increase of the PL37-MAP-triggered elevation of the intracellular calcium content in the GT1-7 cells demonstrating that the effect of E2 might be related to the presence of estrogen receptor. Real-time PCR experiments revealed that E2 increased the expression of C5aR mRNA in GT1-7 neurons, suggesting that an increased C5aR synthesis could be involved in the estrogenic modulation of calcium response. These data indicate that hypothalamic neuroendocrine neurons can integrate immune and neuroendocrine functions. Our results may serve a better understanding of the inflammatory and neurodegeneratory diseases of the hypothalamus and the related neuroendocrine and autonomic compensatory responses.

  9. A method for classification of network traffic based on C5.0 Machine Learning Algorithm

    DEFF Research Database (Denmark)

    Bujlow, Tomasz; Riaz, M. Tahir; Pedersen, Jens Myrup

    2012-01-01

    current network traffic. To overcome the drawbacks of existing methods for traffic classification, usage of C5.0 Machine Learning Algorithm (MLA) was proposed. On the basis of statistical traffic information received from volunteers and C5.0 algorithm we constructed a boosted classifier, which was shown...... and classification, an algorithm for recognizing flow direction and the C5.0 itself. Classified applications include Skype, FTP, torrent, web browser traffic, web radio, interactive gaming and SSH. We performed subsequent tries using different sets of parameters and both training and classification options...

  10. Analysis of Pacific Enroute Structure in Support of C-5M Super Galaxy

    Science.gov (United States)

    2015-06-19

    Storyboard ....................................................................................................43 Appendix B. Travis AFB C-5...newest strategic airlifter can be both effective for the combatant commander and efficient for the taxpayer. 42 Appendix A. Storyboard 43

  11. THE DECEPTIVELY SIMPLE THERMOLYSIS OF TRIVALENT PERMETHYLTITANOCENE DERIVATIVES (ETA-5-C5ME5)2TIR - FORMATION OF A TETRAMETHYLFULVENE TITANIUM COMPOUND (ETA-6-C5ME4CH2)(ETA-5-C5ME5)TI AND RH, CATALYZED BY PERMETHYLTITANOCENE HYDRIDE, (ETA-5-C5ME5)2TIH

    NARCIS (Netherlands)

    LUINSTRA, GA; TEUBEN, JH

    1992-01-01

    The complexes Cp*2TiR (Cp* = eta-5-C5Me5; R = Me, Et, n-Pr, C2H3, CH2CMe3, Ph) undergo thermolysis to yield the fulvene complex Cp*FvTi (Fv = eta-6-C5Me4CH2) and RH. Kinetic measurements and deuterium labeling studies show that the decomposition is catalyzed by Cp*2TiH, which is formed either by

  12. The Deceptively Simple Thermolysis of Trivalent Permethyltitanocene Derivatives (η5-C5Me5)2TiR. Formation of a Tetramethylfulvene Titanium Compound (η6-C5Me4CH2)(η5-C5Me5)Ti and RH, Catalyzed by Permethyltitanocene Hydride, (η5-C5Me5)2TiH

    NARCIS (Netherlands)

    Luinstra, Gerrit A.; Teuben, Jan H.

    1992-01-01

    The complexes Cp*2TiR (Cp* = η5-C5Me5; R = Me, Et, n-Pr, C2H3, CH2CMe3, Ph) undergo thermolysis to yield the fulvene complex Cp*FvTi (Fv = η6-C5Me4CH2) and RH. Kinetic measurements and deuterium labeling studies show that the decomposition is catalyzed by Cp*2TiH, which is formed either by

  13. The upgraded control and instrumentation system of C5 irradiation device

    International Nuclear Information System (INIS)

    Iordache, A.; Ancuta, M.; Gruia, L.; Pulpa, A.; Salistean, E.; Gusescu, G.

    2013-01-01

    C5 capsule is an irradiation device of TRIGA SSR, which is designed for irradiation of structural materials in an inert environment for mechanical behavior characterization and the material microstructure evolution during irradiation. The paper presents the upgraded control and instrumentation system of the C5 irradiation device which was designed and manufactured to enhance the performance of this system for better surveillance and processing the acquired experimental data. (authors)

  14. A bonding study of c-C5H8 adsorption on Pt(111)

    International Nuclear Information System (INIS)

    Simonetti, S.; Jasen, P.; Gonzalez, E.; Juan, A.; Brizuela, G.

    2006-01-01

    The chemisorption of cyclopentane (c-C 5 H 8 ) on Pt(111) has been studied using a qualitative band-structure calculations in the framework of tight-binding implementation with the YAeHMOP package. We modeled the metal surface by a two-dimensional slab of finite thickness with an overlayer of c-C 5 H 8 , in a (3x3) di-σ geometry. The c-C 5 H 8 molecule is attached to the surface with its C?C atoms bonded mainly with two Pt atoms while the opposite CH 2 bends towards the surface. The Pt?Pt bonds in the underlying surface and the C?C bonds of c-C 5 H 8 are weakened upon the chemisorption. A noticeable Pt-H and Pt-C interactions has been observed. We found that of Pt 5d z 2 band plays an important role in the bonding between c-C 5 H 8 and the surface, as do the Pt 6s and 6p z bands. The HOMO-LUMO bands of c-C 5 H 8 are very dispersed, indicative of a strong interaction with the metal surface

  15. Hybrid DNA i-motif: Aminoethylprolyl-PNA (pC5) enhance the stability of DNA (dC5) i-motif structure.

    Science.gov (United States)

    Gade, Chandrasekhar Reddy; Sharma, Nagendra K

    2017-12-15

    This report describes the synthesis of C-rich sequence, cytosine pentamer, of aep-PNA and its biophysical studies for the formation of hybrid DNA:aep-PNAi-motif structure with DNA cytosine pentamer (dC 5 ) under acidic pH conditions. Herein, the CD/UV/NMR/ESI-Mass studies strongly support the formation of stable hybrid DNA i-motif structure with aep-PNA even near acidic conditions. Hence aep-PNA C-rich sequence cytosine could be considered as potential DNA i-motif stabilizing agents in vivo conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Model of mouth-to-mouth transfer of bacterial lipoproteins through inner membrane LolC, periplasmic LolA, and outer membrane LolB

    OpenAIRE

    Okuda, Suguru; Tokuda, Hajime

    2009-01-01

    Outer membrane-specific lipoproteins in Escherichia coli are released from the inner membrane by an ATP-binding cassette transporter, the LolCDE complex, which causes the formation of a soluble complex with a periplasmic molecular chaperone, LolA. LolA then transports lipoproteins to the outer membrane where an outer membrane receptor, LolB, incorporates lipoproteins into the outer membrane. The molecular mechanisms underlying the Lol-dependent lipoprotein sorting have been clarified in detai...

  17. Variations in periplasmic loop interactions determine the pH-dependent activity of the hexameric urea transporter UreI from Helicobacter pylori: a molecular dynamics study.

    Science.gov (United States)

    Cáceres-Delpiano, Javier; Teneb, Jaime; Mansilla, Rodrigo; García, Apolinaria; Salas-Burgos, Alexis

    2015-06-26

    Helicobacter pylori is an important factor in the development of diseases such as ulcer and gastric cancer. This bacterium uses a periplasmic transporter, UreI, to deliver urea to the intracelullar space, where later it is transformed into ammonia by the cytoplasmic enzyme urease to survive the acidic condition of the human stomach. The UreI transporter presents a pH-dependent activity, where this pH-dependence remains unknown at a structural level. Althought the existance of several protonable residues in the periplasmic loops are related to the pH-dependent activity, we find interesting to have a clear view of the conformational changes involved in this phenomena through a molecular dynamic study. Molecular dynamic simulations of the UreI transporter at three different pH conditions were performed, revealing two main pH-dependent conformations, which we present as the open and close states. We find that salt bridges between the periplasmic loops are crucial interactions that stabilize these conformations. Besides, a cooperative behaviour exists between the six subunits of the system that is necessary to fulfill the activity of this transporter. We found different pH-dependent conformations of the urea transporter UreI from Helicobacter pylori, which are related to salt-bridge interactions in the periplasmic regions. The behaviour of every channel in the system is not independent, given the existance of a cooperative behaviour through the formation of salt-bridges between the subunits of the hexameric system. We believe that our results will be related to the generation of new eradication therapies using this transporter as an attractive target, denoting that the knowledge of the possible pH-dependent conformations adopted for this transporter are important for the development of rational drug design approximations.

  18. Characterization of Periplasmic Protein BP26 Epitopes of Brucella melitensis Reacting with Murine Monoclonal and Sheep Antibodies

    Science.gov (United States)

    Wu, Jingbo; Zhang, Hui; Wang, Yuanzhi; Qiao, Jun; Chen, Chuangfu; Gao, Goege F.; Allain, Jean-Pierre; Li, Chengyao

    2012-01-01

    More than 35,000 new cases of human brucellosis were reported in 2010 by the Chinese Center for Disease Control and Prevention. An attenuated B. melitensis vaccine M5-90 is currently used for vaccination of sheep and goats in China. In the study, a periplasmic protein BP26 from M5-90 was characterized for its epitope reactivity with mouse monoclonal and sheep antibodies. A total of 29 monoclonal antibodies (mAbs) against recombinant BP26 (rBP26) were produced, which were tested for reactivity with a panel of BP26 peptides, three truncated rBP26 and native BP26 containing membrane protein extracts (NMP) of B. melitensis M5-90 in ELISA and Western-Blot. The linear, semi-conformational and conformational epitopes from native BP26 were identified. Two linear epitopes recognized by mAbs were revealed by 28 of 16mer overlapping peptides, which were accurately mapped as the core motif of amino acid residues 93DRDLQTGGI101 (position 93 to 101) or residues 104QPIYVYPD111, respectively. The reactivity of linear epitope peptides, rBP26 and NMP was tested with 137 sheep sera by ELISAs, of which the two linear epitopes had 65–70% reactivity and NMP 90% consistent with the results of a combination of two standard serological tests. The results were helpful for evaluating the reactivity of BP26 antigen in M5-90. PMID:22457830

  19. Shewanella oneidensis MR-1 nanowires are outer membrane and periplasmic extensions of the extracellular electron transport components.

    Science.gov (United States)

    Pirbadian, Sahand; Barchinger, Sarah E; Leung, Kar Man; Byun, Hye Suk; Jangir, Yamini; Bouhenni, Rachida A; Reed, Samantha B; Romine, Margaret F; Saffarini, Daad A; Shi, Liang; Gorby, Yuri A; Golbeck, John H; El-Naggar, Mohamed Y

    2014-09-02

    Bacterial nanowires offer an extracellular electron transport (EET) pathway for linking the respiratory chain of bacteria to external surfaces, including oxidized metals in the environment and engineered electrodes in renewable energy devices. Despite the global, environmental, and technological consequences of this biotic-abiotic interaction, the composition, physiological relevance, and electron transport mechanisms of bacterial nanowires remain unclear. We report, to our knowledge, the first in vivo observations of the formation and respiratory impact of nanowires in the model metal-reducing microbe Shewanella oneidensis MR-1. Live fluorescence measurements, immunolabeling, and quantitative gene expression analysis point to S. oneidensis MR-1 nanowires as extensions of the outer membrane and periplasm that include the multiheme cytochromes responsible for EET, rather than pilin-based structures as previously thought. These membrane extensions are associated with outer membrane vesicles, structures ubiquitous in Gram-negative bacteria, and are consistent with bacterial nanowires that mediate long-range EET by the previously proposed multistep redox hopping mechanism. Redox-functionalized membrane and vesicular extensions may represent a general microbial strategy for electron transport and energy distribution.

  20. Molybdate binding by ModA, the periplasmic component of the Escherichia coli mod molybdate transport system.

    Science.gov (United States)

    Imperial, J; Hadi, M; Amy, N K

    1998-03-13

    ModA, the periplasmic-binding protein of the Escherichia coli mod transport system was overexpressed and purified. Binding of molybdate and tungstate to ModA was found to modify the UV absorption and fluorescence emission spectra of the protein. Titration of these changes showed that ModA binds molybdate and tungstate in a 1:1 molar ratio. ModA showed an intrinsic fluorescence emission spectrum attributable to its three tryptophanyl residues. Molybdate binding caused a conformational change in the protein characterized by: (i) a shift of tryptophanyl groups to a more hydrophobic environment; (ii) a quenching (at pH 5.0) or enhancement (at pH 7.8) of fluorescence; and (iii) a higher availability of tryptophanyl groups to the polar quencher acrylamide. The tight binding of molybdate did not allow an accurate estimation of the binding constants by these indirect methods. An isotopic binding method with 99MoO42- was used for accurate determination of KD (20 nM) and stoichiometry (1:1 molar ratio). ModA bound tungstate with approximately the same affinity, but did not bind sulfate or phosphate. These KDs are 150- to 250-fold lower than those previously reported, and compatible with the high molybdate transport affinity of the mod system. The affinity of ModA for molybdate was also determined in vivo and found to be similar to that determined in vitro. Copyright 1998 Elsevier Science B.V.

  1. C5 Palsy After Cervical Spine Surgery: A Multicenter Retrospective Review of 59 Cases.

    Science.gov (United States)

    Thompson, Sara E; Smith, Zachary A; Hsu, Wellington K; Nassr, Ahmad; Mroz, Thomas E; Fish, David E; Wang, Jeffrey C; Fehlings, Michael G; Tannoury, Chadi A; Tannoury, Tony; Tortolani, P Justin; Traynelis, Vincent C; Gokaslan, Ziya; Hilibrand, Alan S; Isaacs, Robert E; Mummaneni, Praveen V; Chou, Dean; Qureshi, Sheeraz A; Cho, Samuel K; Baird, Evan O; Sasso, Rick C; Arnold, Paul M; Buser, Zorica; Bydon, Mohamad; Clarke, Michelle J; De Giacomo, Anthony F; Derakhshan, Adeeb; Jobse, Bruce; Lord, Elizabeth L; Lubelski, Daniel; Massicotte, Eric M; Steinmetz, Michael P; Smith, Gabriel A; Pace, Jonathan; Corriveau, Mark; Lee, Sungho; Cha, Peter I; Chatterjee, Dhananjay; Gee, Erica L; Mayer, Erik N; McBride, Owen J; Roe, Allison K; Yanez, Marisa Y; Stroh, D Alex; Than, Khoi D; Riew, K Daniel

    2017-04-01

    A multicenter, retrospective review of C5 palsy after cervical spine surgery. Postoperative C5 palsy is a known complication of cervical decompressive spinal surgery. The goal of this study was to review the incidence, patient characteristics, and outcome of C5 palsy in patients undergoing cervical spine surgery. We conducted a multicenter, retrospective review of 13 946 patients across 21 centers who received cervical spine surgery (levels C2 to C7) between January 1, 2005, and December 31, 2011, inclusive. P values were calculated using 2-sample t test for continuous variables and χ 2 tests or Fisher exact tests for categorical variables. Of the 13 946 cases reviewed, 59 patients experienced a postoperative C5 palsy. The incidence rate across the 21 sites ranged from 0% to 2.5%. At most recent follow-up, 32 patients reported complete resolution of symptoms (54.2%), 15 had symptoms resolve with residual effects (25.4%), 10 patients did not recover (17.0%), and 2 were lost to follow-up (3.4%). C5 palsy occurred in all surgical approaches and across a variety of diagnoses. The majority of patients had full recovery or recovery with residual effects. This study represents the largest series of North American patients reviewed to date.

  2. C5b-9 Staining Correlates With Clinical and Tumor Stage in Gastric Adenocarcinoma.

    Science.gov (United States)

    Chen, Jian; Yang, Wei-Jun; Sun, Hai-Jian; Yang, Xia; Wu, Yu-Zhang

    2016-08-01

    The complement system is a critical part of the immune response, acting in defense against viral infections, clearance of immune complexes, and maintenance of tissue homeostasis. Upregulated expression of the terminal complement complex, C5b-9, has been observed on various tumor cells, such as stomach carcinoma cells, and on cells in the necrotic regions of these tumors as well; however, whether and how C5b-9 is related to gastric cancer progression and severity remains unknown. In this study, human gastric adenocarcinoma (HGAC) tissues (n=47 cases) and patient-matched adjacent nontumoral parenchyma (n=20 cases) were evaluated by tissue microarray and immunohistochemistry. The HGAC tissues showed upregulated C5b-9 expression. Multinomial logistic regression and likelihood ratio testing showed that overexpression of C5b-9 in HGAC tissue was significantly correlated with clinical stage (P=0.007) and tumor stage (P=0.005), but not with tumor distant organ metastasis, lymphoid nodal status, sex, or age. Patients with late-stage gastric adenocarcinoma had a higher amount of tumor cells showing positive staining for C5b-9 than patients with early-stage disease. These results may help in diagnosis and assessment of disease severity of human gastric carcinoma.

  3. Mesenchymal Stem Cells Control Complement C5 Activation by Factor H in Lupus Nephritis

    Directory of Open Access Journals (Sweden)

    Haijun Ma

    2018-06-01

    Full Text Available Lupus nephritis (LN is one of the most severe complications of systemic lupus erythematosus (SLE caused by uncontrolled activation of the complement system. Mesenchymal stem cells (MSCs exhibit clinical efficacy for severe LN in our previous studies, but the underlying mechanisms of MSCs regulating complement activation remain largely unknown. Here we show that significantly elevated C5a and C5b-9 were found in patients with LN, which were notably correlated with proteinuria and different renal pathological indexes of LN. MSCs suppressed systemic and intrarenal activation of C5, increased the plasma levels of factor H (FH, and ameliorated renal disease in lupus mice. Importantly, MSCs transplantation up-regulated the decreased FH in patients with LN. Mechanistically, interferon-α enhanced the secretion of FH by MSCs. These data demonstrate that MSCs inhibit the activation of pathogenic C5 via up-regulation of FH, which improves our understanding of the immunomodulatory mechanisms of MSCs in the treatment of lupus nephritis. Keywords: Lupus nephritis, C5, MSCs, FH

  4. The periplasmic membrane proximal domain of MacA acts as a switch in stimulation of ATP hydrolysis by MacB transporter.

    Science.gov (United States)

    Modali, Sita D; Zgurskaya, Helen I

    2011-08-01

    Escherichia coli MacAB-TolC is a tripartite macrolide efflux transporter driven by hydrolysis of ATP. In this complex, MacA is the periplasmic membrane fusion protein that stimulates the activity of MacB transporter and establishes the link with the outer membrane channel TolC. The molecular mechanism by which MacA stimulates MacB remains unknown. Here, we report that the periplasmic membrane proximal domain of MacA plays a critical role in functional MacA-MacB interactions and stimulation of MacB ATPase activity. Binding of MacA to MacB stabilizes the ATP-bound conformation of MacB, whereas interactions with both MacB and TolC affect the conformation of MacA. A single G353A substitution in the C-terminus of MacA inactivates MacAB-TolC function by changing the conformation of the membrane proximal domain of MacA and disrupting the proper assembly of the MacA-MacB complex. We propose that MacA acts in transport by promoting MacB transition into the closed ATP-bound conformation and in this respect, is similar to the periplasmic solute-binding proteins. © 2011 Blackwell Publishing Ltd.

  5. Overexpression, purification, crystallization and preliminary X-ray crystallographic analysis of the periplasmic domain of outer membrane protein A from Acinetobacter baumannii

    International Nuclear Information System (INIS)

    Park, Jeong Soon; Lee, Woo Cheol; Choi, Saehae; Yeo, Kwon Joo; Song, Jung Hyun; Han, Young-Hyun; Lee, Je Chul; Kim, Seung Il; Jeon, Young Ho; Cheong, Chaejoon; Kim, Hye-Yeon

    2011-01-01

    The crystallization of the OmpA periplasmic domain from A. baumannii is described. Outer membrane protein A from Acinetobacter baumannii (AbOmpA) is a major outer membrane protein and a key player in the bacterial pathogenesis that induces host cell death. AbOmpA is presumed to consist of an N-terminal β-barrel transmembrane domain and a C-terminal periplasmic OmpA-like domain. In this study, the recombinant C-terminal periplasmic domain of AbOmpA was overexpressed in Escherichia coli, purified and crystallized using the vapour-diffusion method. A native diffraction data set was collected to a resolution of 2.0 Å using synchrotron radiation. The space group of the crystal was P2 1 , with unit-cell parameters a = 58.24, b = 98.59, c = 97.96 Å, β = 105.92°. The native crystal contained seven or eight molecules per asymmetric unit and had a calculated Matthews coefficient of 2.93 or 2.56 Å 3 Da −1

  6. A Novel Role for C5a in B-1 Cell Homeostasis

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    Katharina Bröker

    2018-02-01

    Full Text Available B-1 cells constitute a unique subpopulation of lymphocytes residing mainly in body cavities like the peritoneal cavity (PerC but are also found in spleen and bone marrow (BM. As innate-like B cells, they mediate first line immune defense through low-affinity natural IgM (nIgM antibodies. PerC B-1 cells can egress to the spleen and differentiate into nIgM antibody-secreting plasma cells that recognize conserved exogenous and endogenous cellular structures. Homing to and homeostasis within the PerC are regulated by the chemokine CXCL13 released by PerC macrophages and stroma cells. However, the exact mechanisms underlying the regulation of CXCL13 and B-1 homeostasis are not fully explored. B-1 cells play important roles in the inflammatory response to infection, autoimmunity, ischemia/reperfusion injury, obesity, and atherosclerosis. Remarkably, this list of inflammatory entities has a strong overlap with diseases that are regulated by complement suggesting a link between B-1 cells and the complement system. Interestingly, up to now, no data exist regarding the role of complement in B-1 cell biology. Here, we demonstrate for the first time that C5a regulates B-1 cell steady-state dynamics within the peritoneum, the spleen, and the BM. We found decreased B-1a cell numbers in the peritoneum and the spleen of C5aR1−/− mice associated with increased B1-a and B1-b numbers in the spleen and high serum titers of nIgM antibodies directed against phosphorylcholine and several pneumococcal polysaccharides. Similarly, peritoneal B-1a cells were decreased in the peritoneum and splenic B-1a and B-1b cells were increased in C5aR2−/− mice. The decrease in peritoneal B-1 cell numbers was associated with decreased peritoneal CXCL13 levels in C5aR1−/− and C5aR2−/− mice. In search for mechanisms, we found that combined TLR2 and IL-10 receptor activation in PerC macrophages induced strong CXCL13 production, which was significantly reduced in cells

  7. Deposition Velocities of C1 - C5 Alkyl Nitrates at a Northern Colorado Site

    Science.gov (United States)

    Abeleira, A.; Sive, B. C.; Farmer, D.; Swarthout, B.

    2017-12-01

    Organic nitrates (RONO2) are ubiquitous in the troposphere and are part of gas-phase oxidized nitrogen (NOy = NOx + HNO3 + HONO + N2O5 + HO2NO2 + PAN + NO3 + RONO2). RONO2 can act as both sinks and sources of HOx (RO + RO2 + OH) and NOx (NO + NO2), contributing to the nonlinearity of ozone (O3) formation. It is thus potentially important to understand sinks of RONO2, and how they change seasonally, in order to predict O3 on local, regional and global scales. We focus here on speciated C1 - C5 monofunctional alkyl nitrates (C1 - C5 ANs). In polluted continental regions the dominant source of C1 - C5 ANs is the OH-initiated oxidation of parent alkanes in the presence of NO, and thus changes seasonally with OH mixing ratios. Direct emissions of C1 - C2 ANs include oceanic sources and biomass burning. The sinks of C1 - C5 ANs include OH oxidation and photolysis, both of which release O3 precursors. Chemical transport models tend to overestimate the mixing ratios of small ANs indicating that a missing sink is not included. Wet deposition of C1 - C5 ANs is typically ignored due to the very low Henry's Law constants of these species. However, dry deposition of total organic nitrogen has been observed to be substantial. The dry deposition velocity of methyl nitrate has previously been estimated from summer observations at a rural New England site with a value of 0.13 cm s-1. Here we report deposition velocities for C1 - C5 ANs from surface observations at the Boulder Atmospheric Observatory (BAO) in Erie, Colorado during winter 2011 and spring 2015. We calculate deposition velocities from the observed decay in C1 - C5 ANs at night during periods with a stable nocturnal boundary layer height of 100 - 200 meters. Ideal meteorological conditions were observed for 5 nights during the 2011 NACHTT campaign (February - March 2011), and for 5 nights during the 2015 SONGNEX campaign (March - May 2015). Deposition velocities increased with alkyl nitrate size, ranging from 0.15 cm

  8. Inhibition of HIV-1 in vitro by C-5 propyne phosphorothioate antisense to rev

    DEFF Research Database (Denmark)

    Lund, O S; Nielsen, Jens Ole; Hansen, J E

    1995-01-01

    in a sequence-dependent manner. The antiviral effect was obtained by lipofection or simple addition of 0.2-1 microM modified oligodeoxynucleotide to the culture medium of H9 cells chronically infected with the HIV-1LAI isolate of human immunodeficiency virus type 1. We conclude that C-5 propyne...

  9. C2-C5 hydrocarbon measurements in the Netherlands 1981-1991

    NARCIS (Netherlands)

    Roemer, M.; Builtjes, P.; Esser, P.; Guicherit, R.; Thijsse, T.

    1999-01-01

    Measurements of C2-C5 hydrocarbons on an hourly basis at the TNO site in Delft from 1982 to 1984 and at Moerdijk over the period 1981-1991 are presented. In combination with meteorological data (wind direction and wind speed) the Delft and Moerdijk series are evaluated to identify source categories,

  10. Bill C-5, an act to amend the radiation emitting devices act

    International Nuclear Information System (INIS)

    1984-01-01

    This Act, entitled Bill C-5, allows for a series of amendments to the Radiation Emitting Devices Act. The amendments relate to regulations concerned with the sale, lease or import, labelling, advertising, packaging, safety standards and inspection of radiation emitting devices

  11. Release of Periplasmic Nucleotidase Induced by Human Antimicrobial Peptide in E. coli Causes Accumulation of the Immunomodulator Adenosine.

    Directory of Open Access Journals (Sweden)

    Andreia Bergamo Estrela

    Full Text Available Previous work by our group described that human β-defensin-2 induces accumulation of extracellular adenosine (Ado in E. coli cultures through a non-lytic mechanism causing severe plasmolysis. Here, we investigate the presence of AMP as a direct precursor and the involvement of a bacterial enzyme in the generation of extracellular Ado by treated bacteria. Following hBD-2 treatment, metabolites were quantified in the supernatants using targeted HPLC-MS/MS analysis. Microbial growth was monitored by optical density and cell viability was determined by colony forming units counts. Phosphatase activity was measured using chromogenic substrate pNPP. The results demonstrate that defensin-treated E. coli strain W releases AMP in the extracellular space, where it is converted to Ado by a bacterial soluble factor. An increase in phosphatase activity in the supernatant was observed after peptide treatment, similar to the effect of sucrose-induced osmotic stress, suggesting that the periplasmic 5'nucleotidase (5'-NT is released following the plasmolysis event triggered by the peptide. Ado accumulation was enhanced in the presence of Co2+ ion and inhibited by EDTA, further supporting the involvement of a metallo-phosphatase such as 5'-NT in extracellular AMP conversion into Ado. The comparative analysis of hBD-induced Ado accumulation in different E. coli strains and in Pseudomonas aeruginosa revealed that the response is not correlated to the peptide's effect on cell viability, but indicates it might be dependent on the subcellular distribution of the nucleotidase. Taken together, these data shed light on a yet undescribed mechanism of host-microbial interaction: a human antimicrobial peptide inducing selective release of a bacterial enzyme (E. coli 5'-NT, leading to the formation of a potent immunomodulator metabolite (Ado.

  12. 17 CFR 240.19c-5 - Governing the multiple listing of options on national securities exchanges.

    Science.gov (United States)

    2010-04-01

    ... of options on national securities exchanges. 240.19c-5 Section 240.19c-5 Commodity and Securities... of Exchange Members § 240.19c-5 Governing the multiple listing of options on national securities exchanges. (a) The rules of each national securities exchange that provides a trading market in standardized...

  13. Effective ionization coefficient of C5 perfluorinated ketone and its mixtures with air

    Science.gov (United States)

    Aints, Märt; Jõgi, Indrek; Laan, Matti; Paris, Peeter; Raud, Jüri

    2018-04-01

    C5 perfluorinated ketone (C5 PFK with UIPAC chemical name 1,1,1,3,4,4,4-heptafluoro-3-(trifluoromethyl)-2-butanone and sold by 3M as Novec™ 5110) has a high dielectric strength and a low global warming potential, which makes it interesting as an insulating gas in medium and high-voltage applications. The study was carried out to determine the effective Townsend ionization coefficient α eff as a function of electric field strength and gas density for C5 PFK and for its mixtures with air. The non-self-sustained Townsend discharge between parallel plate electrodes was initiated by illuminating the cathode by UV radiation. The discharge current, I, was measured as a function of inter-electrode distance, d, at different gas densities, N, and electric field strengths, E. The effective ionization coefficient α eff was determined from the semi-logarithmic plots of I/I 0 against d. For each tested gas mixture, the density normalized effective ionization coefficient α eff/N was found to be a unique function of reduced electric field strength E/N. The measurements were carried out in the absolute pressure range of 0.05-1.3 bar and E/N range of 150-1200 Td. The increasing fraction of C5 PFK in air resulted in the decrease of effective ionization coefficient. The limiting electric field strength (E/N)lim where the effective ionization coefficient α eff became zero was 770 Td (190 kV cm-1 at 1 bar) for pure C5 PFK and decreased to 225 Td (78 kV cm-1 at 1.4 bar) for 7.6% C5 PFK/air mixture. The latter value of (E/N)lim is still more than two times higher than the (E/N)lim value of synthetic air and about two-thirds of the value corresponding to pure SF6. The investigated gas mixtures have the potential to become an alternative to SF6 in numerous high- and medium-voltage applications.

  14. Granulocyte and monocyte CD11b expression during plasma separation is dependent on complement factor 5 (C5) - an ex vivo study with blood from a C5-deficient individual.

    Science.gov (United States)

    Hardersen, Randolf; Enebakk, Terje; Christiansen, Dorte; Bergseth, Grethe; Brekke, Ole-Lars; Mollnes, Tom Eirik; Lappegård, Knut Tore; Hovland, Anders

    2018-04-01

    The aim of the study was to investigate the role of complement factor 5 (C5) in reactions elicited by plasma separation using blood from a C5-deficient (C5D) individual, comparing it to C5-deficient blood reconstituted with C5 (C5DR) and blood from healthy donors. Blood was circulated through an ex vivo plasma separation model. Leukocyte CD11b expression and leukocyte-platelet conjugates were measured by flow cytometry during a 30-min period. Other markers were assessed during a 240-min period. Granulocyte and monocyte CD11b expression did not increase in C5D blood during plasma separation. In C5DR samples granulocytes CD11b expression, measured by mean fluorescence intensity (MFI), increased from 10481 ± 6022 (SD) to 62703 ± 4936, and monocytes CD11b expression changed from 13837 ± 7047 to 40063 ± 713. Granulocyte-platelet conjugates showed a 2.5-fold increase in the C5DR sample compared to the C5D sample. Monocyte-platelet conjugates increased independently of C5. In the C5D samples, platelet count decreased from 210 × 10 9 /L (201-219) (median and range) to 51 × 10 9 /L (50-51), and C3bc increased from 14 CAU/mL (21-7) to 198 CAU/mL (127-269), whereas TCC formation was blocked during plasma separation. In conclusion, up-regulation of granulocyte and monocyte CD11b during plasma separation was C5-dependent. The results also indicate C5 dependency in granulocyte-platelet conjugates formation. © 2018 APMIS. Published by John Wiley & Sons Ltd.

  15. Complement Receptors C5aR and C5L2 Are Associated with Metabolic Profile, Sex Hormones, and Liver Enzymes in Obese Women Pre- and Postbariatric Surgery

    Directory of Open Access Journals (Sweden)

    Reza Rezvani

    2014-01-01

    Full Text Available Objective. Obesity is associated with metabolic dysfunction with sex differences and chronic, low-grade inflammation. We proposed that hepatic expression of immune complement C3 related receptors (C3aR, C5aR, and C5L2 would be associated with pre- or postmenopausal status and metabolic profile in severely obese women. We hypothesized that C5L2/C5aR ratio, potentially influencing the ASP/C5L2 metabolic versus C5a/C5aR immune response, would predict metabolic profiles after weight loss surgery. Materials and Methods. Fasting plasma (hormone, lipid, and enzyme analysis and liver biopsies (RT-PCR gene expression were obtained from 91 women during surgery. Results. Hepatic C5L2 mRNA expression was elevated in pre- versus postmenopausal women (P<0.01 and correlated positively with circulating estradiol, estrone, ApoB, ApoA1, ApoA1/B, waist circumference, age, and LDL-C (all P<0.05. While plasma ASP was lower in pre- versus postmenopausal women (P<0.01, the hepatic C5L2/C5aR mRNA ratio was increased (P<0.001 and correlated positively with estrone (P<0.01 and estradiol (P<0.001 and negatively with circulating ApoB and liver enzymes ALT, AST, and GGT (all P<0.05. Over 12 months postoperatively, liver enzymes in low C5L2/C5aR mRNA ratio group remained higher (ALP and ALT, P<0.05, AST and GGT, P<0.001 2-way-ANOVA. Conclusion. C5L2-C5aR association with other mediators including estrogens may contribute to hepatic metabolic and inflammatory function.

  16. Effect of Bacillus pumilus CCIBP-C5 on Musa-Pseudocercospora fijiensis interaction.

    Science.gov (United States)

    Cruz-Martín, Mileidy; Acosta-Suárez, Mayra; Mena, Eilyn; Roque, Berkis; Pichardo, Tatiana; Alvarado-Capó, Yelenys

    2018-02-01

    The effect of antifungal activity of culture filtrate (CF) of Bacillus pumilus strain CCIBP-C5, an isolate from a phyllosphere of banana ( Musa ) leaves, was determined on Pseudocercospora fijiensis challenged banana plants. The CF was shown to decrease the fungal biomass and induce changes in banana plant. In this sense, at 70 days post inoculation (dpi), a lower infection index as well as a decrease in fungal biomass after 6 dpi was obtained in treated plants with respect to control ones. At the same time, changes in the activities of several enzymes related to plant defense responses, such as phenylalanine ammonia lyase, chitinases, β-1,3-glucanases and peroxidases were observed. These results indicate that B. pumilus CCIBP-C5 has a potential role for biological control of P. fijiensis possibly due to the production of antifungal metabolites.

  17. Optical waveguides in LiTaO3 crystals fabricated by swift C5+ ion irradiation

    International Nuclear Information System (INIS)

    Liu, Guiyuan; He, Ruiyun; Akhmadaliev, Shavkat; Vázquez de Aldana, Javier R.; Zhou, Shengqiang; Chen, Feng

    2014-01-01

    We report on the optical waveguides, in both planar and ridge configurations, fabricated in LiTaO 3 crystal by using carbon (C 5+ ) ions irradiation at energy of 15 MeV. The planar waveguide was produced by direct irradiation of swift C 5+ ions, whilst the ridge waveguides were manufactured by using femtosecond laser ablation of the planar layer. The reconstructed refractive index profile of the planar waveguide has showed a barrier-shaped distribution, and the near-field waveguide mode intensity distribution was in good agreement with the calculated modal profile. After thermal annealing at 260 °C in air, the propagation losses of both the planar and ridge waveguides were reduced to 10 dB/cm

  18. Release of (14C)5-hydroxytryptamine from human platelets by red wine

    International Nuclear Information System (INIS)

    Jarman, J.; Glover, V.; Sandler, M.

    1991-01-01

    Red wine, at a final dilution of 1/50, caused released of ( 14 C)5-hydroxytryptamine (5-HT) from preloaded platelets, an effect which was not observed with any white wines or beers tested. Since 5-HT, is probably released from body stores during migraine attacks and red wine is known to provoke migraine episodes in susceptible individuals, release of 5-HT, possibly from central stores, could represent a plausible mechanism for its mode of action

  19. Synthesis and thermolysis of Cp*(C5Me4CH2)TiR complexes

    NARCIS (Netherlands)

    Luinstra, GA; Brinkmann, PHP; Teuben, JH; Luinstra, Gerrit A.

    1997-01-01

    Substitution of the chloride in Cp*FvTiCl with MR (Fv = C5Me4CH2; R = Me, CH2SiMe3, CH2CMe3, CH = CH2, M = Li; R = CH2Ph, M = K; R = C3H5, M = MgCl; R = Ph, M = Na . NaCl) gives Cp*FvTiR. NMR spectroscopic evidence points towards a series of structurally related compounds with a bent-sandwich

  20. Comparison of neutral density profiles measured using Dα and C5+ in NSTX-U

    Science.gov (United States)

    Bell, R. E.; Scotti, F.; Diallo, A.; Leblanc, B. P.; Podesta, M.; Sabbagh, S. A.

    2017-10-01

    Edge neutral density profiles determined from two different measurements are compared on NSTX-U plasmas. Neutral density measurements were not typical on NSTX plasmas. An array of fibers dedicated to the measurement of passive emission of C5+, used to subtract background emission for charge exchange recombination spectroscopy (CHERS), can be used to infer deuterium neutral density near the plasma edge. The line emission from C5+ is dominated by charge exchange with neutral deuterium near the plasma edge. An edge neutral density diagnostic consisting of a camera with a Dα filter was installed on NSTX-U. The line-integrated measurements from both diagnostics are inverted to obtain local emissivity profiles. Neutral density is then inferred using atomics rates from ADAS and profile measurements from Thomson scattering and CHERS. Comparing neutral density profiles from the two diagnostic measurements helps determine the utility of using the more routinely available C5+ measurements for neutral density profiles. Initial comparisons show good agreement between the two measurements inside the separatrix. Supported by US DoE Contracts DE-AC02-09CH11466 and DE-AC52-07NA27344.

  1. TrpC5 Mediates Acute Leptin and Serotonin Effects via Pomc Neurons

    Directory of Open Access Journals (Sweden)

    Yong Gao

    2017-01-01

    Full Text Available The molecular mechanisms underlying acute leptin and serotonin 2C receptor-induced hypophagia remain unclear. Here, we show that neuronal and pro-opiomelanocortin (Pomc-specific loss of transient receptor potential cation 5 (TrpC5 subunits is sufficient to decrease energy expenditure and increase food intake resulting in elevated body weight. Deficiency of Trpc5 subunits in Pomc neurons is also sufficient to block the anorexigenic effects of leptin and serotonin 2C receptor (Ht2Cr agonists. The loss of acute anorexigenic effects of these receptors is concomitant with a blunted electrophysiological response to both leptin and Ht2Cr agonists in arcuate Pomc neurons. We also demonstrate that the Ht2Cr agonist lorcaserin-induced improvements in glucose and insulin tolerance are blocked by TrpC5 deficiency in Pomc neurons. Together, our results link TrpC5 subunits in the brain with leptin- and serotonin 2C receptor-dependent changes in neuronal activity, as well as energy balance, feeding behavior, and glucose metabolism.

  2. The periplasmic transaminase PtaA of Pseudomonas fluorescens converts the glutamic acid residue at the pyoverdine fluorophore to α-ketoglutaric acid.

    Science.gov (United States)

    Ringel, Michael T; Dräger, Gerald; Brüser, Thomas

    2017-11-10

    The periplasmic conversion of ferribactin to pyoverdine is essential for siderophore biogenesis in fluorescent pseudomonads, such as pathogenic Pseudomonas aeruginosa or plant growth-promoting Pseudomonas fluorescens The non-ribosomal peptide ferribactin undergoes cyclizations and oxidations that result in the fluorophore, and a strictly conserved fluorophore-bound glutamic acid residue is converted to a range of variants, including succinamide, succinic acid, and α-ketoglutaric acid residues. We recently discovered that the pyridoxal phosphate-containing enzyme PvdN is responsible for the generation of the succinamide, which can be hydrolyzed to succinic acid. Based on this, a distinct unknown enzyme was postulated to be responsible for the conversion of the glutamic acid to α-ketoglutaric acid. Here we report the identification and characterization of this enzyme in P. fluorescens strain A506. In silico analyses indicated a periplasmic transaminase in fluorescent pseudomonads and other proteobacteria that we termed PtaA for " p eriplasmic t ransaminase A " An in-frame-deleted ptaA mutant selectively lacked the α-ketoglutaric acid form of pyoverdine, and recombinant PtaA complemented this phenotype. The ptaA / pvdN double mutant produced exclusively the glutamic acid form of pyoverdine. PtaA is homodimeric and contains a pyridoxal phosphate cofactor. Mutation of the active-site lysine abolished PtaA activity and affected folding as well as Tat-dependent transport of the enzyme. In pseudomonads, the occurrence of ptaA correlates with the occurrence of α-ketoglutaric acid forms of pyoverdines. As this enzyme is not restricted to pyoverdine-producing bacteria, its catalysis of periplasmic transaminations is most likely a general tool for specific biosynthetic pathways. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  3. Molecular and expression analysis of complement component C5 in the nurse shark (Ginglymostoma cirratum) and its predicted functional role.

    Science.gov (United States)

    Graham, Matthew; Shin, Dong-Ho; Smith, Sylvia L

    2009-07-01

    We present the complete cDNA sequence of shark (Ginglymostoma cirratum) pro-C5 and its molecular characterization with a descriptive analysis of the structural elements necessary for its potential functional role as a potent mediator of inflammation (fragment C5a) and initiator molecule (fragment C5b) for the assembly of the membrane attack complex (MAC) upon activation by C5 convertase. In mammals the three complement activation cascades, the classical, alternative and lectin pathways, converge at the activation of C3, a pivotal complement protein. It is, however, the subsequent activation of the next complement component, C5, which is the focal point at which the initiation of the terminal lytic pathway takes place and involves the stepwise assembly of the MAC. The effector cytolytic function of complement occurs with the insertion of MAC into target membranes causing dough-nut like holes and cell leakage. The lytic activity of shark complement results in structurally similar holes in target membranes suggesting the assembly of a shark MAC that likely involves a functional analogue of C5. The composition of shark MAC remains unresolved and to date conclusive evidence has been lacking for shark C5. The gene has not been cloned nor has the serum protein been characterized for any elasmobranch species. This report is the first to confirm the presence of C5 homologue in the shark. GcC5 is remarkably similar to human C5 in overall structure and domain arrangement. The GcC5 cDNA measured 5160-bp with 5' and 3' UTRs of 35 bp and 79 bp, respectively. Structural analysis of the derived protein sequence predicts a molecule that is a two-chain structure which lacks a thiolester bond and contains a C5 convertase cleavage site indicating that activation will generate two peptides, akin to C5b and C5a. The putative GcC5 molecule also contains the C-terminal C345C/Netrin module that characterizes C3, C4 and C5. Multiple alignment of deduced amino acid sequences shows that GcC5

  4. Cloning, expression, cellular distribution, and role in chemotaxis of a C5a receptor in rainbow trout: the first identification of a C5a receptor in a nonmammalian species

    Science.gov (United States)

    Boshra, Hani; Li, Jun; Peters, Rodney; Hansen, John; Matlapudi, Anjan; Sunyer, J. Oriol

    2004-01-01

    C3a, C4a, and C5a anaphylatoxins generated during complement activation play a key role in inflammation. C5a is the most potent of the three anaphylatoxins in eliciting biological responses. The effects of C5a are mediated by its binding to C5a receptor (C5aR, CD88). To date, C5aR has only been identified and cloned in mammalian species, and its evolutionary history remains ill-defined. To gain insights into the evolution, conserved structural domains, and functions of C5aR, we have cloned and characterized a C5aR in rainbow trout, a teleost fish. The isolated cDNA encoded a 350-aa protein that showed the highest sequence similarity to C5aR from other species. Genomic analysis revealed the presence of one continuous exon encoding the entire open reading frame. Northern blot analysis showed significant expression of the trout C5a receptor (TC5aR) message in PBLs and kidney. Flow cytometric analysis showed that two Abs generated against two different areas of the extracellular N-terminal region of TC5aR positively stained the same leukocyte populations from PBLs. B lymphocytes and granulocytes comprised the majority of cells recognized by the anti-TC5aR. More importantly, these Abs inhibited chemotaxis of PBLs toward a chemoattractant fraction purified from complement-activated trout serum. Our data suggest that the split between C5aR and C3aR from a common ancestral molecule occurred before the emergence of teleost fish. Moreover, we demonstrate that the overall structure of C5aR as well as its role in chemotaxis have remained conserved for >300 million years.

  5. Analysis on Biomechanical Characteristics of Post-operational Vertebral C5-C6 Segments

    Directory of Open Access Journals (Sweden)

    Heqiang Tian

    2016-03-01

    Full Text Available Both anterior cervical decompression and fusion (ACDF and artificial cervical disc replacement (ACDR have obvious advantages in the treatment of cervical spondylosis. To analyze the operation results, it is absolutely necessary to study the biomechanics of the movement range of post-operational vertebral C5-C6 segments, especially the biomechanical characteristics in cervical tissues in actual movements. In this study, using the human vertebral 3D graph gained by imaging diagnosis (CT, a vertebral solid model is established by the 3D reconstruction algorithm and reverse engineering technology. After that, with cervical soft tissue structure added to the solid model and set with a joint contact mechanism, a finite element model with a complete, accurate cervical C5-C6 kinematic unit is constructed, based on relevant physiological anatomical knowledge. This model includes vertebral segments, an intervertebral disc, ligament and zygopophysis in the cervical C5-C6 kinematic unit. In the created vertebral finite element model, the model is amended, referring to ACDF and ACDR, and the load and constraint are applied to a normal group, a fusion group and a displacement group, so as to analyze the biomechanical characteristics of the cervical vertebra after ACDF and ACDR. By comparing the finite element simulation results of different surgeries, this paper is intended to evaluate the functions and biomechanical behaviors of the post-operational vertebra, and explore the influence of the operation on the biomechanical stability of the cervical vertebra. This will provide theoretical guidance for implementation and optimization of ACDF and ACDR.

  6. Heparan sulfate C5-epimerase is essential for heparin biosynthesis in mast cells.

    Science.gov (United States)

    Feyerabend, Thorsten B; Li, Jin-Ping; Lindahl, Ulf; Rodewald, Hans-Reimer

    2006-04-01

    Biosynthesis of heparin, a mast cell-derived glycosaminoglycan with widespread importance in medicine, has not been fully elucidated. In biosynthesis of heparan sulfate (HS), a structurally related polysaccharide, HS glucuronyl C5-epimerase (Hsepi) converts D-glucuronic acid (GlcA) to L-iduronic acid (IdoA) residues. We have generated Hsepi-null mouse mutant mast cells, and we show that the same enzyme catalyzes the generation of IdoA in heparin and that 'heparin' lacking IdoA shows a distorted O-sulfation pattern.

  7. C5a Receptor (CD88) Blockade Protects against MPO-ANCA GN

    OpenAIRE

    Xiao, Hong; Dairaghi, Daniel J.; Powers, Jay P.; Ertl, Linda S.; Baumgart, Trageen; Wang, Yu; Seitz, Lisa C.; Penfold, Mark E.T.; Gan, Lin; Hu, Peiqi; Lu, Bao; Gerard, Norma P.; Gerard, Craig; Schall, Thomas J.; Jaen, Juan C.

    2013-01-01

    Necrotizing and crescentic GN (NCGN) with a paucity of glomerular immunoglobulin deposits is associated with ANCA. The most common ANCA target antigens are myeloperoxidase (MPO) and proteinase 3. In a manner that requires activation of the alternative complement pathway, passive transfer of antibodies to mouse MPO (anti-MPO) induces a mouse model of ANCA NCGN that closely mimics human disease. Here, we confirm the importance of C5aR/CD88 in the mediation of anti-MPO–induced NCGN and report th...

  8. MacA, a periplasmic membrane fusion protein of the macrolide transporter MacAB-TolC, binds lipopolysaccharide core specifically and with high affinity.

    Science.gov (United States)

    Lu, Shuo; Zgurskaya, Helen I

    2013-11-01

    The Escherichia coli MacAB-TolC transporter has been implicated in efflux of macrolide antibiotics and secretion of enterotoxin STII. In this study, we found that purified MacA, a periplasmic membrane fusion protein, contains one tightly bound rough core lipopolysaccharide (R-LPS) molecule per MacA molecule. R-LPS was bound specifically to MacA protein with affinity exceeding that of polymyxin B. Sequence analyses showed that MacA contains two high-density clusters of positively charged amino acid residues located in the cytoplasmic N-terminal domain and the periplasmic C-terminal domain. Substitutions in the C-terminal cluster reducing the positive-charge density completely abolished binding of R-LPS. At the same time, these substitutions significantly reduced the functionality of MacA in the protection of E. coli against macrolides in vivo and in the in vitro MacB ATPase stimulation assays. Taken together, our results suggest that R-LPS or a similar glycolipid is a physiological substrate of MacAB-TolC.

  9. Crystallization and preliminary X-ray diffraction analysis of the periplasmic domain of the Escherichia coli aspartate receptor Tar and its complex with aspartate

    Energy Technology Data Exchange (ETDEWEB)

    Mise, Takeshi; Matsunami, Hideyuki; Samatey, Fadel A.; Maruyama, Ichiro N., E-mail: ichi@oist.jp [Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Kunigami, Okinawa 904-0495 (Japan)

    2014-08-27

    The periplasmic domain of the E. coli aspartate receptor Tar was cloned, expressed, purified and crystallized with and without bound ligand. The crystals obtained diffracted to resolutions of 1.58 and 1.95 Å, respectively. The cell-surface receptor Tar mediates bacterial chemotaxis toward an attractant, aspartate (Asp), and away from a repellent, Ni{sup 2+}. To understand the molecular mechanisms underlying the induction of Tar activity by its ligands, the Escherichia coli Tar periplasmic domain with and without bound aspartate (Asp-Tar and apo-Tar, respectively) were each crystallized in two different forms. Using ammonium sulfate as a precipitant, crystals of apo-Tar1 and Asp-Tar1 were grown and diffracted to resolutions of 2.10 and 2.40 Å, respectively. Alternatively, using sodium chloride as a precipitant, crystals of apo-Tar2 and Asp-Tar2 were grown and diffracted to resolutions of 1.95 and 1.58 Å, respectively. Crystals of apo-Tar1 and Asp-Tar1 adopted space group P4{sub 1}2{sub 1}2, while those of apo-Tar2 and Asp-Tar2 adopted space groups P2{sub 1}2{sub 1}2{sub 1} and C2, respectively.

  10. Periplasmic Cu,Zn superoxide dismutase and cytoplasmic Dps concur in protecting Salmonella enterica serovar Typhimurium from extracellular reactive oxygen species.

    Science.gov (United States)

    Pacello, Francesca; Ceci, Pierpaolo; Ammendola, Serena; Pasquali, Paolo; Chiancone, Emilia; Battistoni, Andrea

    2008-02-01

    Several bacteria possess periplasmic Cu,Zn superoxide dismutases which can confer protection from extracellular reactive oxygen species. Thus, deletion of the sodC1 gene reduces Salmonella enterica serovar Typhimurium ability to colonize the spleens of wild type mice, but enhances virulence in p47phox mutant mice. To look into the role of periplamic Cu,Zn superoxide dismutase and into possible additive effects of the ferritin-like Dps protein involved in hydrogen peroxide detoxification, we have analyzed bacterial survival in response to extracellular sources of superoxide and/or hydrogen peroxide. Exposure to extracellular superoxide of Salmonella Typhimurium mutant strains lacking the sodC1 and sodC2 genes and/or the dps gene does not cause direct killing of bacteria, indicating that extracellular superoxide is poorly bactericidal. In contrast, all mutant strains display a sharp hydrogen peroxide-dependent loss of viability, the dps,sodC1,sodC2 mutant being less resistant than the dps or the sodC1,sodC2 mutants. These findings suggest that the role of Cu,Zn superoxide dismutase in bacteria is to remove rapidly superoxide from the periplasm to prevent its reaction with other reactive molecules. Moreover, the nearly additive effect of the sodC and dps mutations suggests that localization of antioxidant enzymes in different cellular compartments is required for bacterial resistance to extracytoplasmic oxidative attack.

  11. Ligand size is a major determinant of specificity in periplasmic oxyanion-binding proteins: the 1.2 A resolution crystal structure of Azotobacter vinelandii ModA.

    Science.gov (United States)

    Lawson, D M; Williams, C E; Mitchenall, L A; Pau, R N

    1998-12-15

    . Periplasmic receptors constitute a diverse class of binding proteins that differ widely in size, sequence and ligand specificity. Nevertheless, almost all of them display a common beta/alpha folding motif and have similar tertiary structures consisting of two globular domains. The ligand is bound at the bottom of a deep cleft, which lies at the interface between these two domains. The oxyanion-binding proteins are notable in that they can discriminate between very similar ligands. . Azotobacter vinelandii is unusual in that it possesses two periplasmic molybdate-binding proteins. The crystal structure of one of these with bound ligand has been determined at 1.2 A resolution. It superficially resembles the structure of sulphate-binding protein (SBP) from Salmonella typhimurium and uses a similar constellation of hydrogen-bonding interactions to bind its ligand. However, the detailed interactions are distinct from those of SBP and the more closely related molybdate-binding protein of Escherichia coli. . Despite differences in the residues involved in binding, the volumes of the binding pockets in the A. vinelandii and E. coli molybdate-binding proteins are similar and are significantly larger than that of SBP. We conclude that the discrimination between molybdate and sulphate shown by these binding proteins is largely dependent upon small differences in the sizes of these two oxyanions.

  12. Intelligent Diagnostic Assistant for Complicated Skin Diseases through C5's Algorithm.

    Science.gov (United States)

    Jeddi, Fatemeh Rangraz; Arabfard, Masoud; Kermany, Zahra Arab

    2017-09-01

    Intelligent Diagnostic Assistant can be used for complicated diagnosis of skin diseases, which are among the most common causes of disability. The aim of this study was to design and implement a computerized intelligent diagnostic assistant for complicated skin diseases through C5's Algorithm. An applied-developmental study was done in 2015. Knowledge base was developed based on interviews with dermatologists through questionnaires and checklists. Knowledge representation was obtained from the train data in the database using Excel Microsoft Office. Clementine Software and C5's Algorithms were applied to draw the decision tree. Analysis of test accuracy was performed based on rules extracted using inference chains. The rules extracted from the decision tree were entered into the CLIPS programming environment and the intelligent diagnostic assistant was designed then. The rules were defined using forward chaining inference technique and were entered into Clips programming environment as RULE. The accuracy and error rates obtained in the training phase from the decision tree were 99.56% and 0.44%, respectively. The accuracy of the decision tree was 98% and the error was 2% in the test phase. Intelligent diagnostic assistant can be used as a reliable system with high accuracy, sensitivity, specificity, and agreement.

  13. 3-D extension C5G7 MOX benchmark calculation using threedant code

    International Nuclear Information System (INIS)

    Kim, H.Ch.; Han, Ch.Y.; Kim, J.K.; Na, B.Ch.

    2005-01-01

    It pursued the benchmark on deterministic 3-D MOX fuel assembly transport calculations without spatial homogenization (C5G7 MOX Benchmark Extension). The goal of this benchmark is to provide a more through test results for the abilities of current available 3-D methods to handle the spatial heterogeneities of reactor core. The benchmark requires solutions in the form of normalized pin powers as well as the eigenvalue for each of the control rod configurations; without rod, with A rods, and with B rods. In this work, the DANTSYS code package was applied to analyze the 3-D Extension C5G7 MOX Benchmark problems. The THREEDANT code within the DANTSYS code package, which solves the 3-D transport equation in x-y-z, and r-z-theta geometries, was employed to perform the benchmark calculations. To analyze the benchmark with the THREEDANT code, proper spatial and angular approximations were made. Several calculations were performed to investigate the effects of the different spatial approximations on the accuracy. The results from these sensitivity studies were analyzed and discussed. From the results, it is found that the 4*4 grid per pin cell is sufficiently refined so that very little benefit is obtained by increasing the mesh size. (authors)

  14. C5 Benchmark Problem with Discrete Ordinate Radiation Transport Code DENOVO

    Energy Technology Data Exchange (ETDEWEB)

    Yesilyurt, Gokhan [ORNL; Clarno, Kevin T [ORNL; Evans, Thomas M [ORNL; Davidson, Gregory G [ORNL; Fox, Patricia B [ORNL

    2011-01-01

    The C5 benchmark problem proposed by the Organisation for Economic Co-operation and Development/Nuclear Energy Agency was modeled to examine the capabilities of Denovo, a three-dimensional (3-D) parallel discrete ordinates (S{sub N}) radiation transport code, for problems with no spatial homogenization. Denovo uses state-of-the-art numerical methods to obtain accurate solutions to the Boltzmann transport equation. Problems were run in parallel on Jaguar, a high-performance supercomputer located at Oak Ridge National Laboratory. Both the two-dimensional (2-D) and 3-D configurations were analyzed, and the results were compared with the reference MCNP Monte Carlo calculations. For an additional comparison, SCALE/KENO-V.a Monte Carlo solutions were also included. In addition, a sensitivity analysis was performed for the optimal angular quadrature and mesh resolution for both the 2-D and 3-D infinite lattices of UO{sub 2} fuel pin cells. Denovo was verified with the C5 problem. The effective multiplication factors, pin powers, and assembly powers were found to be in good agreement with the reference MCNP and SCALE/KENO-V.a Monte Carlo calculations.

  15. CYP4F18-Deficient Neutrophils Exhibit Increased Chemotaxis to Complement Component C5a

    Directory of Open Access Journals (Sweden)

    Rachel Vaivoda

    2015-01-01

    Full Text Available CYP4Fs were first identified as enzymes that catalyze hydroxylation of leukotriene B4 (LTB4. CYP4F18 has an unusual expression in neutrophils and was predicted to play a role in regulating LTB4-dependent inflammation. We compared chemotaxis of wild-type and Cyp4f18 knockout neutrophils using an in vitro assay. There was no significant difference in the chemotactic response to LTB4, but the response to complement component C5a increased 1.9–2.25-fold in knockout cells compared to wild-type (P < 0.01. This increase was still observed when neutrophils were treated with inhibitors of eicosanoid synthesis. There were no changes in expression of other CYP4 enzymes in knockout neutrophils that might compensate for loss of CYP4F18 or lead to differences in activity. A mouse model of dextran sodium sulfate colitis was used to investigate the consequences of increased C5a-dependent chemotaxis in vivo, but there was no significant difference in weight loss, disease activity, or colonic tissue myeloperoxidase between wild-type and Cyp4f18 knockout mice. This study demonstrates the limitations of inferring CYP4F function based on an ability to use LTB4 as a substrate, points to expanding roles for CYP4F enzymes in immune regulation, and underscores the in vivo challenges of CYP knockout studies.

  16. Crystallographic characterization of divalent organosamarium compound (C5H5)2Sm(THF)2

    International Nuclear Information System (INIS)

    Jagannatha Swamy, S.

    2002-01-01

    The single pot reaction between SmX 2 (X = Cl - , I - ) and BuLi in THF at -40 degC, followed by the addition of C 5 H 5 - Na + results in a dark red solution. Leaving the concentrated reaction mixture at -25 degC for two days in a deep freezer results in the formation of the crystals of the compound, (C 5 H 5 ) 2 ; Sm(THF) 2 . The compound is insoluble in any solvent and it has been characterized by conventional methods. The crystals are monoclinic with space group C2/c, and a = 13.416(1), b = 9.644(1), c = 14.129(2) pm, β109.873(9) 0 and z = 4 for ρcalcd = 1.64 g cm -3 . Least squares refinement on the basis of 1804 observed reflections has led to a final R value of 0.037 and R w = 0.054. (author)

  17. C5a enhances dysregulated inflammatory and angiogenic responses to malaria in vitro: potential implications for placental malaria.

    Directory of Open Access Journals (Sweden)

    Andrea Conroy

    Full Text Available Placental malaria (PM is a leading cause of maternal and infant mortality. Although the accumulation of parasitized erythrocytes (PEs and monocytes within the placenta is thought to contribute to the pathophysiology of PM, the molecular mechanisms underlying PM remain unclear. Based on the hypothesis that excessive complement activation may contribute to PM, in particular generation of the potent inflammatory peptide C5a, we investigated the role of C5a in the pathogenesis of PM in vitro and in vivo.Using primary human monocytes, the interaction between C5a and malaria in vitro was assessed. CSA- and CD36-binding PEs induced activation of C5 in the presence of human serum. Plasmodium falciparum GPI (pfGPI enhanced C5a receptor expression (CD88 on monocytes, and the co-incubation of monocytes with C5a and pfGPI resulted in the synergistic induction of cytokines (IL-6, TNF, IL-1beta, and IL-10, chemokines (IL-8, MCP-1, MIP1alpha, MIP1beta and the anti-angiogenic factor sFlt-1 in a time and dose-dependent manner. This dysregulated response was abrogated by C5a receptor blockade. To assess the potential role of C5a in PM, C5a plasma levels were measured in malaria-exposed primigravid women in western Kenya. Compared to pregnant women without malaria, C5a levels were significantly elevated in women with PM.These results suggest that C5a may contribute to the pathogenesis of PM by inducing dysregulated inflammatory and angiogenic responses that impair placental function.

  18. Scientific Impact of MODIS C5 Calibration Degradation and C6+ Improvements

    Science.gov (United States)

    Lyapustin, A.; Wang, Y.; Xiong, X.; Meister, G.; Platnick, S.; Levy, R.; Franz, B.; Korkin, S.; Hilker, T.; Tucker, J.; hide

    2014-01-01

    The Collection 6 (C6) MODIS (Moderate Resolution Imaging Spectroradiometer) land and atmosphere data sets are scheduled for release in 2014. C6 contains significant revisions of the calibration approach to account for sensor aging. This analysis documents the presence of systematic temporal trends in the visible and near-infrared (500 m) bands of the Collection 5 (C5) MODIS Terra and, to lesser extent, in MODIS Aqua geophysical data sets. Sensor degradation is largest in the blue band (B3) of the MODIS sensor on Terra and decreases with wavelength. Calibration degradation causes negative global trends in multiple MODIS C5 products including the dark target algorithm's aerosol optical depth over land and Ångstrom exponent over the ocean, global liquid water and ice cloud optical thickness, as well as surface reflectance and vegetation indices, including the normalized difference vegetation index (NDVI) and enhanced vegetation index (EVI). As the C5 production will be maintained for another year in parallel with C6, one objective of this paper is to raise awareness of the calibration-related trends for the broad MODIS user community. The new C6 calibration approach removes major calibrations trends in the Level 1B (L1B) data. This paper also introduces an enhanced C6C calibration of the MODIS data set which includes an additional polarization correction (PC) to compensate for the increased polarization sensitivity of MODIS Terra since about 2007, as well as detrending and Terra- Aqua cross-calibration over quasi-stable desert calibration sites. The PC algorithm, developed by the MODIS ocean biology processing group (OBPG), removes residual scan angle, mirror side and seasonal biases from aerosol and surface reflectance (SR) records along with spectral distortions of SR. Using the multiangle implementation of atmospheric correction (MAIAC) algorithm over deserts, we have also developed a detrending and cross-calibration method which removes residual decadal trends on

  19. Relationship between a novel polymorphism of the C5L2 gene and coronary artery disease.

    Directory of Open Access Journals (Sweden)

    Ying-Ying Zheng

    Full Text Available BACKGROUND: C5L2 has been demonstrated to be a functional receptor of acylation-stimulating protein (ASP, which is a stimulator of triglyceride synthesis or glucose transport. However, little is known about the variations in the coding region of the C5L2 gene and their association with coronary artery disease (CAD. METHODOLOGY/PRINCIPAL FINDINGS: We identified a novel single nucleotide polymorphism (SNP, 698C>T (P233L, in exon 2 using a polymerase chain reaction direct-sequencing method. This nucleotide change causes the amino-acid order from proline to leucine at codon 233. We examined the role of this SNP for CAD using two independent case-control studies: one was in the Han population (492 CAD patients and 577 control subjects and the other was in the Uygur population (319 CAD patients and 554 control subjects. Heterozygote carriers of the 698CT genotype were more frequent among CAD patients than among controls not only in the Han population (7.3% versus 1.7% but also in the Uygur population (4.7% versus 1.6%. The odds ratio (OR for carriers of the 698CT genotype for CAD was 4.484 (95% confidence interval (CI: 2.197-9.174 in the Han group and 2.989 (95% CI: 1.292-6.909 in the Uygur population. After adjustment of confounding factors such as sex, age, smoking, alcohol consumption, hypertension, diabetes, as well as serum levels of triglyceride, total cholesterol, high-density lipoprotein, the difference remained significant in the Han group (P<0.001, OR = 6.604, 95% CI: 2.776-15.711 and in the Uygur group (P = 0.047, OR = 2.602, 95% CI: 1.015-6.671. CONCLUSION/SIGNIFICANCE: The 698CT genotype of C5L2 may be a genetic maker of CAD in the Han and Uygur population in western China.

  20. Verification of the shift Monte Carlo code with the C5G7 reactor benchmark

    International Nuclear Information System (INIS)

    Sly, N. C.; Mervin, B. T.; Mosher, S. W.; Evans, T. M.; Wagner, J. C.; Maldonado, G. I.

    2012-01-01

    Shift is a new hybrid Monte Carlo/deterministic radiation transport code being developed at Oak Ridge National Laboratory. At its current stage of development, Shift includes a parallel Monte Carlo capability for simulating eigenvalue and fixed-source multigroup transport problems. This paper focuses on recent efforts to verify Shift's Monte Carlo component using the two-dimensional and three-dimensional C5G7 NEA benchmark problems. Comparisons were made between the benchmark eigenvalues and those output by the Shift code. In addition, mesh-based scalar flux tally results generated by Shift were compared to those obtained using MCNP5 on an identical model and tally grid. The Shift-generated eigenvalues were within three standard deviations of the benchmark and MCNP5-1.60 values in all cases. The flux tallies generated by Shift were found to be in very good agreement with those from MCNP. (authors)

  1. Attila calculations for the 3-D C5G7 benchmark extension

    International Nuclear Information System (INIS)

    Wareing, T.A.; McGhee, J.M.; Barnett, D.A.; Failla, G.A.

    2005-01-01

    The performance of the Attila radiation transport software was evaluated for the 3-D C5G7 MOX benchmark extension, a follow-on study to the MOX benchmark developed by the 'OECD/NEA Expert Group on 3-D Radiation Transport Benchmarks'. These benchmarks were designed to test the ability of modern deterministic transport methods to model reactor problems without spatial homogenization. Attila is a general purpose radiation transport software package with an integrated graphical user interface (GUI) for analysis, set-up and postprocessing. Attila provides solutions to the discrete-ordinates form of the linear Boltzmann transport equation on a fully unstructured, tetrahedral mesh using linear discontinuous finite-element spatial differencing in conjunction with diffusion synthetic acceleration of inner iterations. The results obtained indicate that Attila can accurately solve the benchmark problem without spatial homogenization. (authors)

  2. Pericles and Attila results for the C5G7 MOX benchmark problems

    International Nuclear Information System (INIS)

    Wareing, T.A.; McGhee, J.M.

    2002-01-01

    Recently the Nuclear Energy Agency has published a new benchmark entitled, 'C5G7 MOX Benchmark.' This benchmark is to test the ability of current transport codes to treat reactor core problems without spatial homogenization. The benchmark includes both a two- and three-dimensional problem. We have calculated results for these benchmark problems with our Pericles and Attila codes. Pericles is a one-,two-, and three-dimensional unstructured grid discrete-ordinates code and was used for the twodimensional benchmark problem. Attila is a three-dimensional unstructured tetrahedral mesh discrete-ordinate code and was used for the three-dimensional problem. Both codes use discontinuous finite element spatial differencing. Both codes use diffusion synthetic acceleration (DSA) for accelerating the inner iterations.

  3. Heteronuclear three-dimensional NMR spectroscopy of the inflammatory protein C5a

    International Nuclear Information System (INIS)

    Zuiderweg, E.R.P.; Fesik, S.W.

    1989-01-01

    The utility of three-dimensional heteronuclear NMR spectroscopy for the assignment of 1 H and 15 N resonances of the inflammatory protein C5a (MW 8500), uniformly labeled with 15 N, is demonstrated at a protein concentration of 0.7 mM. It is shown that dramatic simplification of the 2D nuclear Overhauser effect spectrum (NOESY) is obtained by editing with respect to the frequency of the 15 N heteronucleus in a third dimension. The improved resolution in the 3D experiment largely facilitates the assignment of protein NMR spectra and allows for the determination of distance constraints from otherwise overlapping NOE cross peaks for purposes of 3D structure determination. The results show that 15 N heteronuclear 3D NMR can facilitate the structure determination of small proteins and promises to be a useful tool for the study of larger systems that cannot be studied by conventional 2D NMR techniques

  4. Heteronuclear three-dimensional NMR spectroscopy of the inflammatory protein C5a

    Energy Technology Data Exchange (ETDEWEB)

    Zuiderweg, E.R.P.; Fesik, S.W. (Abbott Laboratories, Abbott Park, IL (USA))

    1989-03-21

    The utility of three-dimensional heteronuclear NMR spectroscopy for the assignment of {sup 1}H and {sup 15}N resonances of the inflammatory protein C5a (MW 8500), uniformly labeled with {sup 15}N, is demonstrated at a protein concentration of 0.7 mM. It is shown that dramatic simplification of the 2D nuclear Overhauser effect spectrum (NOESY) is obtained by editing with respect to the frequency of the {sup 15}N heteronucleus in a third dimension. The improved resolution in the 3D experiment largely facilitates the assignment of protein NMR spectra and allows for the determination of distance constraints from otherwise overlapping NOE cross peaks for purposes of 3D structure determination. The results show that {sup 15}N heteronuclear 3D NMR can facilitate the structure determination of small proteins and promises to be a useful tool for the study of larger systems that cannot be studied by conventional 2D NMR techniques.

  5. Randomized Trial of C5a Receptor Inhibitor Avacopan in ANCA-Associated Vasculitis.

    Science.gov (United States)

    Jayne, David R W; Bruchfeld, Annette N; Harper, Lorraine; Schaier, Matthias; Venning, Michael C; Hamilton, Patrick; Burst, Volker; Grundmann, Franziska; Jadoul, Michel; Szombati, István; Tesař, Vladimír; Segelmark, Mårten; Potarca, Antonia; Schall, Thomas J; Bekker, Pirow

    2017-09-01

    Alternative C activation is involved in the pathogenesis of ANCA-associated vasculitis. However, glucocorticoids used as treatment contribute to the morbidity and mortality of vasculitis. We determined whether avacopan (CCX168), an orally administered, selective C5a receptor inhibitor, could replace oral glucocorticoids without compromising efficacy. In this randomized, placebo-controlled trial, adults with newly diagnosed or relapsing vasculitis received placebo plus prednisone starting at 60 mg daily (control group), avacopan (30 mg, twice daily) plus reduced-dose prednisone (20 mg daily), or avacopan (30 mg, twice daily) without prednisone. All patients received cyclophosphamide or rituximab. The primary efficacy measure was the proportion of patients achieving a ≥50% reduction in Birmingham Vasculitis Activity Score by week 12 and no worsening in any body system. We enrolled 67 patients, 23 in the control and 22 in each of the avacopan groups. Clinical response at week 12 was achieved in 14 of 20 (70.0%) control patients, 19 of 22 (86.4%) patients in the avacopan plus reduced-dose prednisone group (difference from control 16.4%; two-sided 90% confidence limit, -4.3% to 37.1%; P =0.002 for noninferiority), and 17 of 21 (81.0%) patients in the avacopan without prednisone group (difference from control 11.0%; two-sided 90% confidence limit, -11.0% to 32.9%; P =0.01 for noninferiority). Adverse events occurred in 21 of 23 (91%) control patients, 19 of 22 (86%) patients in the avacopan plus reduced-dose prednisone group, and 21 of 22 (96%) patients in the avacopan without prednisone group. In conclusion, C5a receptor inhibition with avacopan was effective in replacing high-dose glucocorticoids in treating vasculitis. Copyright © 2017 by the American Society of Nephrology.

  6. Impact of the surgical strategy on the incidence of C5 nerve root palsy in decompressive cervical surgery.

    Directory of Open Access Journals (Sweden)

    Theresa Krätzig

    Full Text Available Our aim was to identify the impact of different surgical strategies on the incidence of C5 palsy.Degenerative cervical spinal stenosis is a steadily increasing morbidity in the ageing population. Postoperative C5 nerve root palsy is a common complication with severe impact on the patients´ quality of life.We identified 1708 consecutive patients who underwent cervical decompression surgery due to degenerative changes. The incidence of C5 palsy and surgical parameters including type and level of surgery were recorded to identify predictors for C5 nerve palsy.The overall C5 palsy rate was 4.8%, with 18.3% of cases being bilateral. For ACDF alone the palsy rate was low (1.13%, compared to 14.0% of C5 palsy rate after corpectomy. The risk increased with extension of the procedures. Hybrid constructs with corpectomy plus ACDF at C3-6 showed significantly lower rates of C5 palsy (10.7% than corpectomy of two vertebrae (p = 0.005. Multiple regression analysis identified corpectomy of C4 or C5 as a significant predictor. We observed a lower overall incidence for ventral (4.3% compared to dorsal (10.9% approaches (p<0.001. When imaging detected a postoperative shift of the spinal cord at index segment C4/5, palsy rate increased significantly (33.3% vs. 12.5%, p = 0.034.Extended surgical strategies, such as dorsal laminectomies, multilevel corpectomies and procedures with extensive spinal cord shift were shown to display a high risk of C5 palsy. The use of extended procedures should therefore be employed cautiously. Switching to combined surgical methods like ACDF plus corpectomy can reduce the rate of C5 palsy.

  7. Evaluation of SF6-alternative gas C5-PFK based on arc extinguishing performance and electric strength

    Science.gov (United States)

    Wu, Yi; Wang, Chunlin; Sun, Hao; Rong, Mingzhe; Murphy, Anthony Bruce; Li, Tianwei; Zhong, Jianying; Chen, Zhexin; Yang, Fei; Niu, Chunpin

    2017-09-01

    C5-PFK (C5-perfluoroketone, C5F10O) is under wide consideration as an environmentally-friendly alternative gas to SF6 in high-voltage applications, because of its superior insulation performance. The aim of this work is to study theoretically the arc extinguishing performance and electric strength of C5-PFK. The arc extinguishing performance of C5-PFK was evaluated by analyzing and comparing the thermophysical properties of C5-PFK, SF6, CF4, CO2 and N2 plasmas. It was difficult to obtain the species formed in C5-PFK plasmas because of the complex C5-PFK molecular decomposition process. In this work, the decomposition process of C5-PFK and the related species were analyzed by the bond energy analysis method. For the species for which parameters such as the partition function and the enthalpy of formation were not available, computational chemistry methods were used to obtain the required data. The collision integrals were calculated using the phenomenological potential model. Using these results, the local thermodynamic equilibrium composition at temperatures from 300 to 30 000 K at 1-10 atm of pure C5-PFK was calculated by the method of minimization of the Gibbs free energy, and the corresponding transport coefficients were calculated by Chapman-Enskog method. Through the comparison of the thermophysical properties, it was found that C5-PFK had similar characteristics to SF6, with large peaks in specific heat below 4500 K, indicating potentially good thermal interruption capability. However, the specific heat peak at 7000 K corresponding to CO decomposition may detract from the thermal interruption capability. Specific heat peaks at higher temperatures are associated with the breaking of double or triple bonds, and should be avoided if possible in the new alternative gases. The electric strength of C5-PFK was assessed using the molecular electrostatic potential, which can be accurately calculated or measured, and gives strong insights into important

  8. Heterogeneity of d-glucuronyl C5-epimerase expression and epigenetic regulation in prostate cancer

    International Nuclear Information System (INIS)

    Prudnikova, Tatiana Y; Soulitzis, Nikolaos; Kutsenko, Olesya S; Mostovich, Lyudmila A; Haraldson, Klas; Ernberg, Ingemar; Kashuba, Vladimir I; Spandidos, Demetrios A; Zabarovsky, Eugene R; Grigorieva, Elvira V

    2013-01-01

    Heparansulfate proteoglycans (HSPG) play an important role in cell–cell and cell–matrix interactions and signaling, and one of the key enzymes in heparansulfate biosynthesis is d-glucuronyl C5-epimerase (GLCE). A tumor suppressor function has been demonstrated for GLCE in breast and lung carcinogenesis; however, no data are available as to the expression and regulation of the gene in prostate cancer. In this study, decreased GLCE expression was observed in 10% of benign prostate hyperplasia (BPH) tissues and 53% of prostate tumors, and increased GLCE mRNA levels were detected in 49% of BPH tissues and 21% of tumors. Statistical analysis showed a positive correlation between increased GLCE expression and Gleason score, TNM staging, and prostate-specific antigen (PSA) level in the prostate tumors (Pearson correlation coefficients GLCE/Gleason = 0.56, P < 0.05; GLCE/TNM = 0.62, P < 0.05; and GLCE/PSA = 0.88, P < 0.01), suggesting GLCE as a candidate molecular marker for advanced prostate cancer. Immunohistochemical analysis revealed an intratumoral heterogeneity of GLCE protein levels both in BPH and prostate cancer cells, resulting in a mixed population of GLCE-expressing and nonexpressing epithelial cells in vivo. A model experiment on normal (PNT2) and prostate cancer (LNCaP, PC3, DU145) cell lines in vitro showed a 1.5- to 2.5-fold difference in GLCE expression levels between the cancer cell lines and an overall decrease in GLCE expression in cancer cells. Methyl-specific polymerase chain reaction (PCR), bisulfite sequencing, and deoxy-azacytidin (aza-dC) treatment identified differential GLCE promoter methylation (LNCaP 70–72%, PC3 32–35%, DU145, and PNT2 no methylation), which seems to contribute to heterogeneous GLCE expression in prostate tumors. The obtained results reveal the complex deregulation of GLCE expression in prostatic diseases compared with normal prostate tissue and suggest that GLCE may be used as a potential model to study the functional

  9. Classification of a Haemophilus influenzae ABC Transporter HI1470/71 through Its Cognate Molybdate Periplasmic Binding Protein, MolA

    Energy Technology Data Exchange (ETDEWEB)

    Tirado-Lee, Leidamarie; Lee, Allen; Rees, Douglas C.; Pinkett, Heather W. (CIT); (NWU)

    2014-10-02

    molA (HI1472) from H. influenzae encodes a periplasmic binding protein (PBP) that delivers substrate to the ABC transporter MolB{sub 2}C{sub 2} (formerly HI1470/71). The structures of MolA with molybdate and tungstate in the binding pocket were solved to 1.6 and 1.7 {angstrom} resolution, respectively. The MolA-binding protein binds molybdate and tungstate, but not other oxyanions such as sulfate and phosphate, making it the first class III molybdate-binding protein structurally solved. The {approx}100 {mu}M binding affinity for tungstate and molybdate is significantly lower than observed for the class II ModA molybdate-binding proteins that have nanomolar to low micromolar affinity for molybdate. The presence of two molybdate loci in H. influenzae suggests multiple transport systems for one substrate, with molABC constituting a low-affinity molybdate locus.

  10. Calculation of thermodynamic properties and transport coefficients of C5F10O-CO2 thermal plasmas

    Science.gov (United States)

    Li, Xingwen; Guo, Xiaoxue; Murphy, Anthony B.; Zhao, Hu; Wu, Jian; Guo, Ze

    2017-10-01

    The thermodynamic properties and transport coefficients of C5F10O-CO2 gas mixtures, which are being considered as substitutes for SF6 in circuit breaker applications, are calculated for the temperature range from 300 K to 30 000 K and the pressure range from 0.05 MPa to 1.6 MPa. Special attention is paid on investigating the evolution of thermophysical properties of C5F10O-CO2 mixtures with different mixing ratios and with different pressures; both the mixing ratio and pressure significantly affect the properties. This is explained mainly in terms of the changes in the temperatures at which the dissociation and ionization reactions take place. Comparisons of different thermophysical properties of C5F10O-CO2 mixtures with those of SF6 are also carried out. It is found that most of the thermophysical properties of the C5F10O-CO2 mixtures, such as thermal conductivity, viscosity, and electrical conductivity, become closer to those of SF6 as the C5F10O concentration increases. The composition and thermophysical properties of pure C5F10O in the temperature range from 300 K to 2000 K based on the decomposition pathway are also given. The calculation results provide a basis for further study of the insulation and arc-quenching capability of C5F10O-CO2 gas mixtures as substitutes for SF6.

  11. Purification of the active C5a receptor from human polymorphonuclear leukocytes as a receptor - G sub i complex

    Energy Technology Data Exchange (ETDEWEB)

    Rollins, T.E.; Siciliano, S.; Kobayashi, S.; Cianciarulo, D.N.; Bonilla-Argudo, V.; Collier, K.; Springer, M.S. (Merck Sharp and Dohme Research Lab., Rahway, NJ (United States))

    1991-02-01

    The authors have isolated, in an active state, the C5a receptor from human polymorphonuclear leukocytes. The purification was achieved in a single step using a C5a affinity column in which the C5a molecule was coupled to the resin through its N terminus. The purified receptor, like the crude solubilized molecule, exhibited a single class of high-affinity binding sites with a K{sub d} of 30 pM. Further, the binding of C5a retained its sensitivity to guanine nucleotides, implying that the purified receptor contained a guanine nucleotide-binding protein (G protein). SDS/PAGE revealed the presence of three polypeptides with molecular masses of 42, 40, and 36 kDa, which were determined to be the C5a-binding subunit and the {alpha} and {beta} subunits of G{sub i}, respectively. The 36- and 40-kDa polypeptides were identified by immunoblotting and by the ability of pertussis toxin to ADP-ribosylate the 40-kDa molecule. These results confirm their earlier hypothesis that the receptor exists as a complex with a G protein in the presence or absence of C5a. The tight coupling between the receptor and G protein should make possible the identification of the G protein(s) involved in the transduction pathways used by C5a to produce its many biological effects.

  12. Purification of the active C5a receptor from human polymorphonuclear leukocytes as a receptor - Gi complex

    International Nuclear Information System (INIS)

    Rollins, T.E.; Siciliano, S.; Kobayashi, S.; Cianciarulo, D.N.; Bonilla-Argudo, V.; Collier, K.; Springer, M.S.

    1991-01-01

    The authors have isolated, in an active state, the C5a receptor from human polymorphonuclear leukocytes. The purification was achieved in a single step using a C5a affinity column in which the C5a molecule was coupled to the resin through its N terminus. The purified receptor, like the crude solubilized molecule, exhibited a single class of high-affinity binding sites with a K d of 30 pM. Further, the binding of C5a retained its sensitivity to guanine nucleotides, implying that the purified receptor contained a guanine nucleotide-binding protein (G protein). SDS/PAGE revealed the presence of three polypeptides with molecular masses of 42, 40, and 36 kDa, which were determined to be the C5a-binding subunit and the α and β subunits of G i , respectively. The 36- and 40-kDa polypeptides were identified by immunoblotting and by the ability of pertussis toxin to ADP-ribosylate the 40-kDa molecule. These results confirm their earlier hypothesis that the receptor exists as a complex with a G protein in the presence or absence of C5a. The tight coupling between the receptor and G protein should make possible the identification of the G protein(s) involved in the transduction pathways used by C5a to produce its many biological effects

  13. Comparing the Effectiveness of Sagittal Balance, Foraminal Stenosis, and Preoperative Cord Rotation in Predicting Postoperative C5 Palsy.

    Science.gov (United States)

    Chugh, Arunit J S; Weinberg, Douglas S; Alonso, Fernando; Eubanks, Jason D

    2017-11-01

    Retrospective cohort review. To determine whether preoperative cord rotation is independently correlated with C5 palsy when analyzed alongside measures of sagittal balance and foraminal stenosis. Postoperative C5 palsy is a well-documented complication of cervical procedures with a prevalence of 4%-8%. Recent studies have shown a correlation with preoperative spinal cord rotation. There have been few studies, however, that have examined the role of sagittal balance and foraminal stenosis in the development of C5 palsy. A total of 77 patients who underwent cervical decompression-10 of whom developed C5 palsy-were reviewed. Sagittal balance was assessed using curvature angle and curvature index on radiographs and magnetic resonance image (MRI). Cord rotation was assessed on axial MRI. C4-C5 foraminal stenosis was assessed on sagittal MRI using area measurements and a grading scale. Demographics and information on surgical approach were gathered from chart review. Correlation with C5 palsy was performed by point-biserial, χ, and regression analyses. Point-biserial analysis indicated that only cord rotation showed significance (Pbalance did not correlate with presence of C5 palsy. Logistic regression model yielded cord rotation as the only significant independent predictor of C5 palsy. For every degree of axial cord rotation, the likelihood ratio for suffering a C5 palsy was 3.93 (95% confidence interval, 2.01-8.66; Ppoints to mechanisms other than direct compression as the etiology. In addition, the lack of correlation with postoperative changes in sagittal balance hints that measures of curvature angle and curvature index may not be appropriate to accurately predict this complication. Level 3.

  14. C5 glycolipids of heterocystous cyanobacteria track symbiont abundance in the diatom Hemiaulus hauckii across the tropical North Atlantic

    Science.gov (United States)

    Bale, Nicole J.; Villareal, Tracy A.; Hopmans, Ellen C.; Brussaard, Corina P. D.; Besseling, Marc; Dorhout, Denise; Sinninghe Damsté, Jaap S.; Schouten, Stefan

    2018-03-01

    Diatom-diazotroph associations (DDAs) include marine heterocystous cyanobacteria found as exosymbionts and endosymbionts in multiple diatom species. Heterocysts are the site of N2 fixation and have thickened cell walls containing unique heterocyst glycolipids which maintain a low oxygen environment within the heterocyst. The endosymbiotic cyanobacterium Richelia intracellularis found in species of the diatom genus Hemiaulus and Rhizosolenia makes heterocyst glycolipids (HGs) which are composed of C30 and C32 diols and triols with pentose (C5) moieties that are distinct from limnetic cyanobacterial HGs with predominantly hexose (C6) moieties. Here we applied a method for analysis of intact polar lipids to the study of HGs in suspended particulate matter (SPM) and surface sediment from across the tropical North Atlantic. The study focused on the Amazon plume region, where DDAs are documented to form extensive surface blooms, in order to examine the utility of C5 HGs as markers for DDAs as well as their transportation to underlying sediments. C30 and C32 triols with C5 pentose moieties were detected in both marine SPM and surface sediments. We found a significant correlation between the water column concentration of these long-chain C5 HGs and DDA symbiont counts. In particular, the concentrations of both the C5 HGs (1-(O-ribose)-3,27,29-triacontanetriol (C5 HG30 triol) and 1-(O-ribose)-3,29,31-dotriacontanetriol (C5 HG32 triol)) in SPM exhibited a significant correlation with the number of Hemiaulus hauckii symbionts. This result strengthens the idea that long-chain C5 HGs can be applied as biomarkers for marine endosymbiotic heterocystous cyanobacteria. The presence of the same C5 HGs in surface sediment provides evidence that they are effectively transported to the sediment and hence have potential as biomarkers for studies of the contribution of DDAs to the paleo-marine N cycle.

  15. Site-directed fluorescence labeling reveals a revised N-terminal membrane topology and functional periplasmic residues in the Escherichia coli cell division protein FtsK.

    Science.gov (United States)

    Berezuk, Alison M; Goodyear, Mara; Khursigara, Cezar M

    2014-08-22

    In Escherichia coli, FtsK is a large integral membrane protein that coordinates chromosome segregation and cell division. The N-terminal domain of FtsK (FtsKN) is essential for division, and the C terminus (FtsKC) is a well characterized DNA translocase. Although the function of FtsKN is unknown, it is suggested that FtsK acts as a checkpoint to ensure DNA is properly segregated before septation. This may occur through modulation of protein interactions between FtsKN and other division proteins in both the periplasm and cytoplasm; thus, a clear understanding of how FtsKN is positioned in the membrane is required to characterize these interactions. The membrane topology of FtsKN was initially determined using site-directed reporter fusions; however, questions regarding this topology persist. Here, we report a revised membrane topology generated by site-directed fluorescence labeling. The revised topology confirms the presence of four transmembrane segments and reveals a newly identified periplasmic loop between the third and fourth transmembrane domains. Within this loop, four residues were identified that, when mutated, resulted in the appearance of cellular voids. High resolution transmission electron microscopy of these voids showed asymmetric division of the cytoplasm in the absence of outer membrane invagination or visible cell wall ingrowth. This uncoupling reveals a novel role for FtsK in linking cell envelope septation events and yields further evidence for FtsK as a critical checkpoint of cell division. The revised topology of FtsKN also provides an important platform for future studies on essential interactions required for this process. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  16. Isolation and characterisation of EfeM, a periplasmic component of the putative EfeUOBM iron transporter of Pseudomonas syringae pv. syringae

    Energy Technology Data Exchange (ETDEWEB)

    Rajasekaran, Mohan B [School of Biological Sciences Harborne Building, Whiteknights Campus, Reading, RG6 6AS (United Kingdom); Structural Biology Unit at The BioCentre, University of Reading, Harborne Building, Whiteknights Campus, Reading, RG6 6AS (United Kingdom); Mitchell, Sue A; Gibson, Trevor M [Structural Biology Unit at The BioCentre, University of Reading, Harborne Building, Whiteknights Campus, Reading, RG6 6AS (United Kingdom); Hussain, Rohanah; Siligardi, Giuliano [Circular Dichroism Group, Diamond Light Source, Chiltern, Oxfordshire,OX11 0DE (United Kingdom); Andrews, Simon C [School of Biological Sciences Harborne Building, Whiteknights Campus, Reading, RG6 6AS (United Kingdom); Watson, Kimberly A, E-mail: k.a.watson@reading.ac.uk [School of Biological Sciences Harborne Building, Whiteknights Campus, Reading, RG6 6AS (United Kingdom); Structural Biology Unit at The BioCentre, University of Reading, Harborne Building, Whiteknights Campus, Reading, RG6 6AS (United Kingdom)

    2010-07-30

    Research highlights: {yields} Bioinformatic analysis reveals EfeM is a metallopeptidase with conserved HXXE motif. {yields} Mass spectrometry confirms EfeM consists of 251 residues, molecular weight 27,772Da. {yields} SRCD spectroscopy shows an {alpha}-helical secondary structure. {yields} Single crystals of EfeM are orthorhombic and diffract to 1.6A resolution. {yields} Space group is P22{sub 1}2{sub 1} with cell dimensions a = 46.74, b = 95.17 and c = 152.61 A. -- Abstract: The EfeM protein is a component of the putative EfeUOBM iron-transporter of Pseudomonas syringae pathovar syringae and is thought to act as a periplasmic, ferrous-iron binding protein. It contains a signal peptide of 34 amino acid residues and a C-terminal 'Peptidase{sub M}75' domain of 251 residues. The C-terminal domain contains a highly conserved 'HXXE' motif thought to act as part of a divalent cation-binding site. In this work, the gene (efeM or 'Psyr{sub 3}370') encoding EfeM was cloned and over-expressed in Escherichia coli, and the mature protein was purified from the periplasm. Mass spectrometry confirmed the identity of the protein (M{sub W} 27,772 Da). Circular dichroism spectroscopy of EfeM indicated a mainly {alpha}-helical structure, consistent with bioinformatic predictions. Purified EfeM was crystallised by hanging-drop vapor diffusion to give needle-shaped crystals that diffracted to a resolution of 1.6 A. This is the first molecular study of a peptidase M75 domain with a presumed iron transport role.

  17. A novel signal transduction protein: Combination of solute binding and tandem PAS-like sensor domains in one polypeptide chain: Periplasmic Ligand Binding Protein Dret_0059

    Energy Technology Data Exchange (ETDEWEB)

    Wu, R. [Midwest Center for Structural Genomics, Argonne National Laboratory, Argonne Illinois 60439; Biosciences Division, Argonne National Laboratory, Argonne Illinois 60439; Wilton, R. [Biosciences Division, Argonne National Laboratory, Argonne Illinois 60439; Cuff, M. E. [Midwest Center for Structural Genomics, Argonne National Laboratory, Argonne Illinois 60439; Biosciences Division, Argonne National Laboratory, Argonne Illinois 60439; Structural Biology Center, Argonne National Laboratory, Argonne Illinois 60439; Endres, M. [Midwest Center for Structural Genomics, Argonne National Laboratory, Argonne Illinois 60439; Babnigg, G. [Midwest Center for Structural Genomics, Argonne National Laboratory, Argonne Illinois 60439; Biosciences Division, Argonne National Laboratory, Argonne Illinois 60439; Edirisinghe, J. N. [Mathematics and Computer Science Division, Argonne National Laboratory, Argonne Illinois 60439; Computation Institute, University of Chicago, Chicago Illinois 60637; Henry, C. S. [Mathematics and Computer Science Division, Argonne National Laboratory, Argonne Illinois 60439; Computation Institute, University of Chicago, Chicago Illinois 60637; Joachimiak, A. [Midwest Center for Structural Genomics, Argonne National Laboratory, Argonne Illinois 60439; Biosciences Division, Argonne National Laboratory, Argonne Illinois 60439; Structural Biology Center, Argonne National Laboratory, Argonne Illinois 60439; Department of Biochemistry and Molecular Biology, University of Chicago, Chicago Illinois 60637; Schiffer, M. [Biosciences Division, Argonne National Laboratory, Argonne Illinois 60439; Pokkuluri, P. R. [Biosciences Division, Argonne National Laboratory, Argonne Illinois 60439

    2017-03-06

    We report the structural and biochemical characterization of a novel periplasmic ligand-binding protein, Dret_0059, from Desulfohalobium retbaense DSM 5692, an organism isolated from the Salt Lake Retba in Senegal. The structure of the protein consists of a unique combination of a periplasmic solute binding protein (SBP) domain at the N-terminal and a tandem PAS-like sensor domain at the C-terminal region. SBP domains are found ubiquitously and their best known function is in solute transport across membranes. PAS-like sensor domains are commonly found in signal transduction proteins. These domains are widely observed as parts of many protein architectures and complexes but have not been observed previously within the same polypeptide chain. In the structure of Dret_0059, a ketoleucine moiety is bound to the SBP, whereas a cytosine molecule is bound in the distal PAS-like domain of the tandem PAS-like domain. Differential scanning flourimetry support the binding of ligands observed in the crystal structure. There is significant interaction between the SBP and tandem PAS-like domains, and it is possible that the binding of one ligand could have an effect on the binding of the other. We uncovered three other proteins with this structural architecture in the non-redundant sequence data base, and predict that they too bind the same substrates. The genomic context of this protein did not offer any clues for its function. We did not find any biological process in which the two observed ligands are coupled. The protein Dret_0059 could be involved in either signal transduction or solute transport.

  18. Model of mouth-to-mouth transfer of bacterial lipoproteins through inner membrane LolC, periplasmic LolA, and outer membrane LolB.

    Science.gov (United States)

    Okuda, Suguru; Tokuda, Hajime

    2009-04-07

    Outer membrane-specific lipoproteins in Escherichia coli are released from the inner membrane by an ATP-binding cassette transporter, the LolCDE complex, which causes the formation of a soluble complex with a periplasmic molecular chaperone, LolA. LolA then transports lipoproteins to the outer membrane where an outer membrane receptor, LolB, incorporates lipoproteins into the outer membrane. The molecular mechanisms underlying the Lol-dependent lipoprotein sorting have been clarified in detail. However, it remained unclear how Lol factors interact with each other to conduct very efficient lipoprotein transfer in the periplasm where ATP is not available. To address this issue, a photo-reactive phenylalanine analogue, p-benzoyl-phenylalanine, was introduced at various positions of LolA and LolB, of which the overall structures are very similar and comprise an incomplete beta-barrel with a hydrophobic cavity inside. Cells expressing LolA or LolB derivatives containing the above analogue were irradiated with UV for in vivo photo-cross-linking. These analyses revealed a hot area in the same region of LolA and LolB, through which LolA and LolB interact with each other. This area is located at the entrance of the hydrophobic cavity. Moreover, this area in LolA is involved in the interaction with a membrane subunit, LolC, whereas no cross-linking occurs between LolA and the other membrane subunit, LolE, or ATP-binding subunit LolD, despite the structural similarity between LolC and LolE. The hydrophobic cavities of LolA and LolB were both found to bind lipoproteins inside. These results indicate that the transfer of lipoproteins through Lol proteins occurs in a mouth-to-mouth manner.

  19. 3-D extension C5G7 MOX benchmark results using PARTISN

    Energy Technology Data Exchange (ETDEWEB)

    Dahl, J.A. [Los Alamos National Laboratory, CCS-4 Transport Methods Group, Los Alamos, NM (United States)

    2005-07-01

    We have participated in the Expert Group of 3-D Radiation Transport Benchmarks' proposed 3-dimensional Extension C5G7 MOX problems using the discrete ordinate transport code PARTISN. The computational mesh was created using the FRAC-IN-THE-BOX code, which produces a volume fraction Cartesian mesh from combinatorial geometry descriptions. k{sub eff} eigenvalues, maximum pin powers, and average fuel assembly powers are reported and compared to a benchmark quality Monte Carlo solution. We also present a two dimensional mesh convergence study examining the affects of using volume fractions to approximate the water-pin cell interface. It appears that the control rod pin cell must be meshed twice as fine as a fuel pin cell in order to achieve the same spatial error when using the volume fraction method to define water channel-pin cell interfaces. It is noted that the previous PARTISN results provided to the OECD/NEA Expert Group on 3-dimensional Radiation Benchmarks contained a cross section error, and therefore should be disregarded.

  20. 3-D extension C5G7 MOX benchmark results using PARTISN

    International Nuclear Information System (INIS)

    Dahl, J.A.

    2005-01-01

    We have participated in the Expert Group of 3-D Radiation Transport Benchmarks' proposed 3-dimensional Extension C5G7 MOX problems using the discrete ordinate transport code PARTISN. The computational mesh was created using the FRAC-IN-THE-BOX code, which produces a volume fraction Cartesian mesh from combinatorial geometry descriptions. k eff eigenvalues, maximum pin powers, and average fuel assembly powers are reported and compared to a benchmark quality Monte Carlo solution. We also present a two dimensional mesh convergence study examining the affects of using volume fractions to approximate the water-pin cell interface. It appears that the control rod pin cell must be meshed twice as fine as a fuel pin cell in order to achieve the same spatial error when using the volume fraction method to define water channel-pin cell interfaces. It is noted that the previous PARTISN results provided to the OECD/NEA Expert Group on 3-dimensional Radiation Benchmarks contained a cross section error, and therefore should be disregarded

  1. The Hydrogen Bonded Structures of Two 5-Bromobarbituric Acids and Analysis of Unequal C5–X and C5–X′ Bond Lengths (X = X′ = F, Cl, Br or Me in 5,5-Disubstituted Barbituric Acids

    Directory of Open Access Journals (Sweden)

    Thomas Gelbrich

    2016-04-01

    Full Text Available The crystal structure of the methanol hemisolvate of 5,5-dibromobarbituric acid (1MH displays an H-bonded layer structure which is based on N–H∙∙∙O=C, N–H∙∙∙O(MeOH and (MeOHO–H∙∙∙O interactions. The barbiturate molecules form an H-bonded substructure which has the fes topology. 5,5′-Methanediylbis(5-bromobarbituric acid 2, obtained from a solution of 5,5-dibromobarbituric acid in nitromethane, displays a N–H···O=C bonded framework of the sxd type. The conformation of the pyridmidine ring and the lengths of the ring substituent bonds C5–X and C5–X′ in crystal forms of 5,5-dibromobarbituric acid and three closely related analogues (X = X′ = Br, Cl, F, Me have been investigated. In each case, a conformation close to a C5-endo envelope is correlated with a significant lengthening of the axial C5–X′ in comparison to the equatorial C5–X bond. Isolated molecule geometry optimizations at different levels of theory confirm that the C5-endo envelope is the global conformational energy minimum of 5,5-dihalogenbarbituric acids. The relative lengthening of the axial bond is therefore interpreted as an inherent feature of the preferred envelope conformation of the pyrimidine ring, which minimizes repulsive interactions between the axial substituent and pyrimidine ring atoms.

  2. Synergistic enhancement of chemokine generation and lung injury by C5a or the membrane attack complex of complement

    DEFF Research Database (Denmark)

    Czermak, B J; Lentsch, A B; Bless, N M

    1999-01-01

    demonstrated synergistic production of C-X-C (macrophage inflammatory protein-2 and cytokine-induced neutrophil chemoattractant) and C-C (macrophage inflammatory protein-1alpha and monocyte chemoattractant-1) chemokines. In the absence of the costimulus, C5a or MAC did not induce chemokine generation....... In in vivo studies, C5a and MAC alone caused limited or no intrapulmonary generation of chemokines, but in the presence of a costimulus (IgG immune complexes) C5a and MAC caused synergistic intrapulmonary generation of C-X-C and C-C chemokines but not of tumor necrosis factor alpha. Under these conditions...... increased neutrophil accumulation occurred, as did lung injury. These observations suggest that C5a and MAC function synergistically with a costimulus to enhance chemokine generation and the intensity of the lung inflammatory response....

  3. Combustion Characteristics of C5 Alcohols and a Skeletal Mechanism for Homogeneous Charge Compression Ignition Combustion Simulation

    KAUST Repository

    Park, Sungwoo

    2015-10-27

    C5 alcohols are considered alternative fuels because they emit less greenhouse gases and fewer harmful pollutants. In this study, the combustion characteristics of 2-methylbutanol (2-methyl-1-butanol) and isopentanol (3-methyl-1-butanol) and their mixtures with primary reference fuels (PRFs) were studied using a detailed chemical kinetic model obtained from merging previously published mechanisms. Ignition delay times of the C5 alcohol/air mixtures were compared to PRFs at 20 and 40 atm. Reaction path analyses were conducted at intermediate and high temperatures to identify the most influential reactions controlling ignition of C5 alcohols. The direct relation graph with expert knowledge methodology was used to eliminate unimportant species and reactions in the detailed mechanism, and the resulting skeletal mechanism was tested at various homogeneous charge compression ignition (HCCI) engine combustion conditions. These simulations were used to investigate the heat release characteristics of the methyl-substituted C5 alcohols, and the results show relatively strong reactions at intermediate temperatures prior to hot ignition. C5 alcohol blending in PRF75 in HCCI combustion leads to a significant decrease of low-temperature heat release (LTHR) and a delay of the main combustion. The heat release features demonstrated by C5 alcohols can be used to improve the design and operation of advanced engine technologies.

  4. The H_6_0Si_6C_5_4 heterofullerene as high-capacity hydrogen storage medium

    International Nuclear Information System (INIS)

    Yong, Yongliang; Zhou, Qingxiao; Li, Xiaohong; Lv, Shijie

    2016-01-01

    With the great success in Si atoms doped C_6_0 fullerene and the well-established methods for synthesis of hydrogenated carbon fullerenes, this leads naturally to wonder whether Si-doped fullerenes are possible for special applications such as hydrogen storage. Here by using first-principles calculations, we design a novel high-capacity hydrogen storage material, H_6_0Si_6C_5_4 heterofullerene, and confirm its geometric stability. It is found that the H_6_0Si_6C_5_4 heterofullerene has a large HOMO-LUMO gap and a high symmetry, indicating it is high chemically stable. Further, our finite temperature simulations indicate that the H_6_0Si_6C_5_4 heterofullerene is thermally stable at 300 K. H_2 molecules would enter into the cage from the Si-hexagon ring because of lower energy barrier. Through our calculation, a maximum of 21 H_2 molecules can be stored inside the H_6_0Si_6C_5_4 cage in molecular form, leading to a gravimetric density of 11.11 wt% for 21H_2@H_6_0Si_6C_5_4 system, which suggests that the hydrogenated Si_6C_5_4 heterofullerene could be suitable as a high-capacity hydrogen storage material.

  5. Tissue Destruction in Bullous Pemphigoid Can Be Complement Independent and May Be Mitigated by C5aR2

    Directory of Open Access Journals (Sweden)

    Christian M. Karsten

    2018-03-01

    Full Text Available Bullous pemphigoid (BP, the most frequent autoimmune bullous disorder, is a paradigmatic autoantibody-mediated disease associated with autoantibodies against BP180 (type XVII collagen, Col17. Several animal models have been developed that reflect important clinical and immunological features of human BP. Complement activation has been described as a prerequisite for blister formation, however, the recent finding that skin lesions can be induced by anti-Col17 F(ab′2 fragments indicates complement-independent mechanisms to contribute to blister formation in BP. Here, C5−/− mice injected with anti-Col17 IgG showed a reduction of skin lesions by about 50% associated with significantly less skin-infiltrating neutrophils compared to wild-type mice. Reduction of skin lesions and neutrophil infiltration was seen independently of the employed anti-Col17 IgG dose. Further, C5ar1−/− mice were protected from disease development, whereas the extent of skin lesions was increased in C5ar2−/− animals. Pharmacological inhibition of C5a receptor 1 (C5aR1 by PMX53 led to reduced disease activity when applied in a prophylactic setting. In contrast, PMX-53 treatment had no effect when first skin lesions had already developed. While C5aR1 was critically involved in neutrophil migration in vitro, its role for Col17-anti-Col17 IgG immune complex-mediated release of reactive oxygen species from neutrophils was less pronounced. Our data demonstrate that complement-dependent and -independent mechanisms coexist in anti-Col17-autoantibody-mediated tissue destruction. C5aR1 and C5aR2 seem to play opposing roles in this process with C5aR1 exerting its primary effect in recruiting inflammatory cells to the skin during the early phase of the disease. Further studies are required to fully understand the role of C5aR2 in autoantibody-mediated skin inflammation.

  6. C5a regulates IL-12+ DC migration to induce pathogenic Th1 and Th17 cells in sepsis.

    Directory of Open Access Journals (Sweden)

    Ning Ma

    Full Text Available OBJECTIVE: It is well known that complement system C5a is excessively activated during the onset of sepsis. However, it is unclear whether C5a can regulate dentritic cells (DCs to stimulate adaptive immune cells such as Th1 and Th17 in sepsis. METHODS: Sepsis was induced by cecal ligation and puncture (CLP. CLP-induced sepsis was treated with anti-C5a or IL-12. IL-12(+DC, IFNγ(+Th1, and IL-17(+Th17 cells were analyzed by flow cytometry. IL-12 was measured by ELISA. RESULTS: Our studies here showed that C5a induced IL-12(+DC cell migration from the peritoneal cavity to peripheral blood and lymph nodes. Furthermore, IL-12(+DC cells induced the expansion of pathogenic IFNγ(+Th1 and IL-17(+Th17 cells in peripheral blood and lymph nodes. Moreover, IL-12, secreted by DC cells in the peritoneal cavity, is an important factor that prevents the development of sepsis. CONCLUSION: Our data suggests that C5a regulates IL-12(+DC cell migration to induce pathogenic Th1 and Th17 cells in sepsis.

  7. Atomic-scale microstructures of Zr2Al3C4 and Zr3Al3C5 ceramics

    International Nuclear Information System (INIS)

    Lin, Z.J.; Zhuo, M.J.; He, L.F.; Zhou, Y.C.; Li, M.S.; Wang, J.Y.

    2006-01-01

    The microstructures of bulk Zr 2 Al 3 C 4 and Zr 3 Al 3 C 5 ceramics have been investigated using transmission electron microscopy and scanning transmission electron microscopy. These two carbides were determined to have a point group 6/mmm and a space group P6 3 /mmc using selected-area electron diffraction and convergent beam electron diffraction. The atomic-scale microstructures of Zr 2 Al 3 C 4 and Zr 3 Al 3 C 5 were investigated through high-resolution imaging and Z-contrast imaging. Furthermore, intergrowth between Zr 2 Al 3 C 4 and Zr 3 Al 3 C 5 was identified. Stacking faults in Zr 3 Al 3 C 5 were found to result from the insertion of an additional Zr-C layer. Cubic ZrC was occasionally identified to be incorporated in elongated Zr 3 Al 3 C 5 grains. In addition, Al may induce a twinned ZrC structure and lead to the formation of ternary zirconium aluminum carbides

  8. Cloning, periplasmic expression, purification and structural characterization of human ribosomal protein L10; Clonagem, expressao, purificacao e caracterizacao estrutural da proteina ribossomal L10 humana recombinante

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Larissa Miranda

    2009-07-01

    The ribosomal protein L10 (RP L10) is a strong candidate to be included in the class of tumor suppressor proteins. This protein, also denominated as QM, is known to participate in the binding of ribosomal subunits 60S and 40S and the translation of mRNAs. It has a molecular weight that varies between 24 and 26 kDa and an isoelectric point of (pI) 10.5. The sequence of the protein QM is highly conserved in mammals, plants, invertebrates, insects and yeast which indicates its critical functions in a cell. As a tumor suppressor, RP L10 has been studied in strains of Wilm's tumor (WT-1) and tumor cells in the stomach, where was observed a decrease in the amount of its mRNA. More recently, the RP L10 was found in low amounts in the early stages of prostate adenoma and showed some mutation in ovarian cancer, what indicates its role as a suppressor protein in the development of these diseases. It has also been described that this protein interacts with c-Jun and c-Yes inhibiting growth factors and consequently, cell division. This work has an important role on the establishment of soluble expression of QM to give base information for further studies on expression that aim to evaluate the specific regions where it acts binding the 60S and 40S ribosomal subunits and translation, as well as its binding to proto-oncogenes. The cDNA for QM protein was amplified by PCR and cloned into periplasmic expression vector p3SN8. The QM protein was expressed in E. coli BL21 (DE3) in the region of cytoplasm and periplasm, the best condition was obtained from the expression of the recombinant plasmid QM p1813{sub Q}M at 25 degree C or 30 degree C, the soluble protein was obtained with small amounts of contaminants. The assays of secondary structure showed that the QM protein is predominantly alpha-helix, but when it loses the folding, this condition changes and the protein is replaced by {beta}- sheet feature. (author)

  9. Penta-SiC5 monolayer: A novel quasi-planar indirect semiconductor with a tunable wide band gap

    Science.gov (United States)

    Naseri, Mosayeb

    2018-03-01

    In this paper, by using of the first principles calculations in the framework of the density functional theory, we systematically investigated the structure, stability, electronic and optical properties of a novel two-dimensional pentagonal monolayer semiconductors namely penta-SiC5 monolayer. Comparing elemental silicon, diamond, and previously reported 2D carbon allotropes, our calculation shows that the predicted penta-SiC5 monolayer has a metastable nature. The calculated results indicate that the predicted monolayer is an indirect semiconductor with a wide band gap of about 2.82 eV by using Heyd-Scuseria-Ernzerhof (HSE06) hybrid functional level of theory which can be effectively tuned by external biaxial strains. The obtained exceptional electronic properties suggest penta-SiC5 monolayer as promising candidates for application in new electronic devices in nano scale.

  10. Antagonistic activity exerted in vitro and in vivo by Lactobacillus casei (strain GG) against Salmonella typhimurium C5 infection.

    Science.gov (United States)

    Hudault, S; Liévin, V; Bernet-Camard, M F; Servin, A L

    1997-02-01

    The aim of this study was to compare the antagonistic properties of Lactobacillus casei GG exerted in vitro against Salmonella typhimurium C5 in a cellular model, cultured enterocyte-like Caco-2 cells, to those exerted in vivo in an animal model, C3H/He/Oujco mice. Our results show that a 1-h contact between the invading strain C5 and either the culture or the supernatant of L. casei GG impeded the invasion by the Salmonella strain in Caco-2 cells, without modifying the viability of the strain. After neutralization at pH 7, no inhibition of the invasion by C5 was observed. The antagonistic activity of L. casei GG was examined in C3H/He/Oujco mice orally infected with C5 as follows: (i) L. casei GG was given daily to conventional animals as a probiotic, and (ii) it was given once to germ-free animals in order to study the effect of the population of L. casei GG established in the different segments of the gut. In vivo experiments show that after a single challenge with C5, this strain survives and persists at a higher level in the feces of the untreated conventional mice than in those of the treated group. In L. casei GG germ-free mice, establishment of L. casei GG in the gut significantly delayed the occurrence of 100% mortality of the animals (15 days after C5 challenge versus 9 days in germ-free mice [P L. casei GG population level in the gut dramatically decreased in these animals.

  11. Indomethacin inhibits the increased airway responsiveness to histamine following inhalation of C5a des Arg in rabbits.

    Science.gov (United States)

    Berend, N; Armour, C L; Black, J L

    1986-08-01

    It has been shown that inhalation of C5a des Arg increases rabbit airway responsiveness to histamine and that this is associated with an influx of neutrophils into the airway walls. This study was undertaken to see if the augmented response to histamine can be blocked by the cyclo-oxygenase inhibitor indomethacin. Spontaneously breathing, anesthetised rabbits were studied in a volume displacement plethysmograph and pulmonary resistance (R1) was measured using the electrical subtraction technique. Histamine does response curves (HDR) were generated by measuring R1 after serial nubulisation of saline and histamine (1, 3, 10, 30 and 100 mg/ml). Aerosols of either saline or C5a des Arg (1.5 ug/ml) were then inhaled by the animals over a time period of 2 min. An HDR was then repeated 4 hours later. In 9 rabbits the inhalation of C5a des Arg resulted in an upward shift of the repeat HDR: the area under the HDR was significantly greater than under the first HDR (p less than 0.05). In 6 rabbits the repeat HDR 4 hours after saline was shifted downwards (N.S.) indicating some degree of tachyphylaxis. When rabbits were pretreated with indomethacin (5 mg/kg i.v.) the repeat HDR following either C5a des Arg (n = 7) or saline (n = 6) were also shifted downwards i.e., the increased airway responsiveness noted after C5a des Arg was abolished. There was no significant difference in baseline saline R1 during the first or second HDR in any group. These results suggest that the increased airway responsiveness following nebulisation of C5a des Arg may be due to release from neutrophils of products of the cyclo-oxygenase pathway.

  12. Sequence-specific assignments in the 1H NMR spectrum of the human inflammatory protein C5a

    International Nuclear Information System (INIS)

    Zuiderweg, E.R.P.; Mollison, K.W.; Henkin, J.; Carter, G.W.

    1988-01-01

    Full sequence-specific assignments for the 1 H NMR lines of the backbone protons of the human complement factor C5a are described and documented. The results were obtained by largely following the methodology developed by Wuethrich et al. Assignments for the majority of the amino acid side chain protons were obtained by using a comparison of double- and triple-quantum-filtered two-dimensional correlated experiments together with the analysis of relayed coherence transfer spectra. The assignments provide the basis for the determination of the thus far unknown three-dimensional structure of C5a from nuclear Overhauser enhancement distance constraints

  13. Structural Data on the Periplasmic Aldehyde Oxidoreductase PaoABC from Escherichia coli: SAXS and Preliminary X-ray Crystallography Analysis

    Directory of Open Access Journals (Sweden)

    Ana Rita Otrelo-Cardoso

    2014-01-01

    Full Text Available The periplasmic aldehyde oxidoreductase PaoABC from Escherichia coli is a molybdenum enzyme involved in detoxification of aldehydes in the cell. It is an example of an αβγ heterotrimeric enzyme of the xanthine oxidase family of enzymes which does not dimerize via its molybdenum cofactor binding domain. In order to structurally characterize PaoABC, X-ray crystallography and small angle X-ray scattering (SAXS have been carried out. The protein crystallizes in the presence of 20% (w/v polyethylene glycol 3350 using the hanging-drop vapour diffusion method. Although crystals were initially twinned, several experiments were done to overcome twinning and lowering the crystallization temperature (293 K to 277 K was the solution to the problem. The non-twinned crystals used to solve the structure diffract X-rays to beyond 1.80 Å and belong to the C2 space group, with cell parameters a = 109.42 Å, b = 78.08 Å, c = 151.77 Å, β = 99.77°, and one molecule in the asymmetric unit. A molecular replacement solution was found for each subunit separately, using several proteins as search models. SAXS data of PaoABC were also collected showing that, in solution, the protein is also an αβγ heterotrimer.

  14. Inactivation of pecS restores the virulence of mutants devoid of osmoregulated periplasmic glucans in the phytopathogenic bacterium Dickeya dadantii.

    Science.gov (United States)

    Bontemps-Gallo, Sébastien; Madec, Edwige; Lacroix, Jean-Marie

    2014-04-01

    Dickeya dadantii is a phytopathogenic enterobacterium that causes soft rot disease in a wide range of plant species. Maceration, an apparent symptom of the disease, is the result of the synthesis and secretion of a set of plant cell wall-degrading enzymes (PCWDEs), but many additional factors are required for full virulence. Among these, osmoregulated periplasmic glucans (OPGs) and the PecS transcriptional regulator are essential virulence factors. Several cellular functions are controlled by both OPGs and PecS. Strains devoid of OPGs display a pleiotropic phenotype including total loss of virulence, loss of motility and severe reduction in the synthesis of PCWDEs. PecS is one of the major regulators of virulence in D. dadantii, acting mainly as a repressor of various cellular functions including virulence, motility and synthesis of PCWDEs. The present study shows that inactivation of the pecS gene restored virulence in a D. dadantii strain devoid of OPGs, indicating that PecS cannot be de-repressed in strains devoid of OPGs.

  15. Production of recombinant disulfide-rich venom peptides for structural and functional analysis via expression in the periplasm of E. coli.

    Directory of Open Access Journals (Sweden)

    Julie K Klint

    Full Text Available Disulfide-rich peptides are the dominant component of most animal venoms. These peptides have received much attention as leads for the development of novel therapeutic agents and bioinsecticides because they target a wide range of neuronal receptors and ion channels with a high degree of potency and selectivity. In addition, their rigid disulfide framework makes them particularly well suited for addressing the crucial issue of in vivo stability. Structural and functional characterization of these peptides necessitates the development of a robust, reliable expression system that maintains their native disulfide framework. The bacterium Escherichia coli has long been used for economical production of recombinant proteins. However, the expression of functional disulfide-rich proteins in the reducing environment of the E. coli cytoplasm presents a significant challenge. Thus, we present here an optimised protocol for the expression of disulfide-rich venom peptides in the periplasm of E. coli, which is where the endogenous machinery for production of disulfide-bonds is located. The parameters that have been investigated include choice of media, induction conditions, lysis methods, methods of fusion protein and peptide purification, and sample preparation for NMR studies. After each section a recommendation is made for conditions to use. We demonstrate the use of this method for the production of venom peptides ranging in size from 2 to 8 kDa and containing 2-6 disulfide bonds.

  16. Latex agglutination using the periplasmic proteins antigen of Brucella melitensis is a successful, rapid, and specific serodiagnostic test for ovine brucellosis.

    Science.gov (United States)

    Ismael, Alaa Bassuny; Swelum, Ayman Abdel-Aziz; Mostafa, Salama A-H; Alhumiany, Abdel-Rahman A

    2016-09-01

    Brucellosis, especially caused by Brucella melitensis, is considered the most-widespread zoonosis in the world, particularly in developing countries. This study was planned to develop an accurate test for diagnosis of ovine brucellosis using a specific hot saline extracted soluble Brucella melitensis periplasmic proteins (SBPPs). The efficacy of the latex agglutination test (LAT) using SBPPs compared to the Rose Bengal test (RBT), buffered plate agglutination test (BPAT), serum agglutination test (SAT), and an indirect enzyme-linked immunosorbent assay (i-ELISA) was evaluated in the field diagnosis of ovine brucellosis. The test performance was evaluated by estimating sensitivity (Se), specificity (Sp), positive predictive value (PPV), negative predictive value (NPV), disease prevalence (DP), positive likelihood ratio (PLR), and negative likelihood ratio (NLR) using test agreement and bacteriological culture in 1777 samples. The false-positive result was significantly (P ⩽0.05) lower in LAT than RBT, BPAT, SAT, and i-ELISA. With reference to test agreement, the Se, Sp, PPV, and PLR were highest (P ⩽0.05) in LAT 99.33%, 99.88%, 98.68%, and 827.25%, respectively. With reference to bacteriological culture, the LAT and i-ELISA tests showed a significant difference in Se with SAT. However, no significant difference in specificity was detected. The DP was 8.44% in the five tests. In conclusion, LAT using SBPPs of B. melitensis could be a suitable serodiagnostic field test for ovine brucellosis, with high sensitivity and specificity. © The Author(s) 2016.

  17. Autoradiographic studies on the distribution of 14C-5,7-dihydroxytryptamine in the brain of new-born rat

    International Nuclear Information System (INIS)

    Lappe, U.

    1982-01-01

    The distribution of intracisternally injected 14 C-5,7-dihydroxy tryptamine (5,7-DHT) in the central nervous system of new-born rat is studied by means of autoradiography. The radio-active neurotoxin is incorporated into the neurones of all known serotonine nucleus groups. This labelling allows a detailed demonstration of the topography of the serotonine neurones in the brain stem of the new-born rat and to compare it with systems obtained by other methods. Serotonine neurones were mapped in 22 representative frontal sections through the brain stem. 14 C-5,7-DHT is incorporated into noradrenergic neurones, too. However, labelling is less marked than in serotonergic neurones. 14 C-5,7-DHT is incorporated at small quantities into the following extraneural elements: fibroblasts of the pia mater/arachnoidea, some endothelical cells of pial vessels, epithelial cells of the plexus choroideus, and subependymal macrophages. 6 h after injection of 25 μg 14 C-5,7-DHT, the vast majority of serotonergic neurones reveal strong degenerative changes which are irreversible. (orig./MG) [de

  18. Compromised neutrophil function and severe bovine E.coli mastitis: is C5a the missing link?

    Science.gov (United States)

    Around the periparturient period and during early lactation dairy cows have an elevated risk for clinical mastitis. The severity of Gram-negative infections during these periods has been correlated with reduced neutrophil functions. In this review we focus on the potential role of C5a in the develop...

  19. Development of a mathematical model describing hydrolysis and co-fermentation of C6 and C5 sugars

    DEFF Research Database (Denmark)

    Morales Rodriguez, Ricardo; Gernaey, Krist; Meyer, Anne S.

    2010-01-01

    saccharification and co-fermentation (SSCF) of C6 and C5 sugars. Model construction has been carried out by combining existing mathematical models for enzymatic hydrolysis on the one hand and co-fermentation on the other hand. An inhibition of ethanol on cellulose conversion was introduced in order to increase...

  20. Combustion Characteristics of C5 Alcohols and a Skeletal Mechanism for Homogeneous Charge Compression Ignition Combustion Simulation

    KAUST Repository

    Park, Sungwoo; Chung, Suk-Ho; Lu, Tianfeng; Sarathy, Mani

    2015-01-01

    ) and their mixtures with primary reference fuels (PRFs) were studied using a detailed chemical kinetic model obtained from merging previously published mechanisms. Ignition delay times of the C5 alcohol/air mixtures were compared to PRFs at 20 and 40 atm. Reaction

  1. A new adsorption isotherm for C5 hydrocarbons on metal–organic framework Cu3(BTC)2

    Czech Academy of Sciences Publication Activity Database

    Zukal, Arnošt; Kubů, Martin

    2015-01-01

    Roč. 21, 1-2 (2015), s. 99-105 ISSN 0929-5607 R&D Projects: GA ČR GA14-07101S Institutional support: RVO:61388955 Keywords : Cu3(BTC)2 * adsorption * C5 hydrocarbons Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.870, year: 2015

  2. Naked (C5Me5)(2)M cations (M = Sc, Ti, and V) and their fluoroarene complexes

    NARCIS (Netherlands)

    Bouwkamp, MW; Budzelaar, PHM; Gercama, J; Morales, ID; de Wolf, J; Meetsma, A; Troyanov, SI; Teuben, JH; Hessen, B; Budzelaar, Peter H.M.; Hierro Morales, Isabel Del; Troyanov, Sergei I.

    2005-01-01

    The ionic metallocene complexes [Cp*M-2][BPh4] (CP* = C5Me5) of the trivalent 3d metals Sc, Ti, and V were synthesized and structurally characterized. For M Sc, the anion interacts weakly with the metal center through one of the phenyl groups, but for M = Ti and V, the cations are naked. They each

  3. Improving medical diagnosis reliability using Boosted C5.0 decision tree empowered by Particle Swarm Optimization.

    Science.gov (United States)

    Pashaei, Elnaz; Ozen, Mustafa; Aydin, Nizamettin

    2015-08-01

    Improving accuracy of supervised classification algorithms in biomedical applications is one of active area of research. In this study, we improve the performance of Particle Swarm Optimization (PSO) combined with C4.5 decision tree (PSO+C4.5) classifier by applying Boosted C5.0 decision tree as the fitness function. To evaluate the effectiveness of our proposed method, it is implemented on 1 microarray dataset and 5 different medical data sets obtained from UCI machine learning databases. Moreover, the results of PSO + Boosted C5.0 implementation are compared to eight well-known benchmark classification methods (PSO+C4.5, support vector machine under the kernel of Radial Basis Function, Classification And Regression Tree (CART), C4.5 decision tree, C5.0 decision tree, Boosted C5.0 decision tree, Naive Bayes and Weighted K-Nearest neighbor). Repeated five-fold cross-validation method was used to justify the performance of classifiers. Experimental results show that our proposed method not only improve the performance of PSO+C4.5 but also obtains higher classification accuracy compared to the other classification methods.

  4. Effects of micro-water on decomposition of the environment-friendly insulating medium C5F10O

    Directory of Open Access Journals (Sweden)

    Song Xiao

    2017-06-01

    Full Text Available SF6 is widely used in all kinds of high-voltage electrical equipment because of its excellent insulation and arc-extinguishing performance. However, this compound leads to serious greenhouse effect, which harms the environment. Many research institutions are now actively in search of SF6 alternative gas. C5F10O has attracted much attention as an alternative gas with low global warming potential (GWP and excellent dielectric strength. In this paper, we analyzed the possible decomposition paths of C5F10O under micro-water environment through density functional theory. We also evaluated the ionization parameters and toxicity of the decomposition products. The results show that OH• and H• produced by H2O exhibited a catalytic effect on the decomposition of C5F10O. CF4, C2F6, C3F6, C3F8, C4F10, C5F12, C6F14, C3F7COH, C3F7OH, CF3COH, C3F7H, and CF3OH were produced in the micro-water environment. Based on molecular configuration calculation, the ionization parameters of these products were inferior to perfluorocarbons, such as C3F8, leading to reduced insulation performance of the system. Moreover, CF2O and HF are hazardous to human health and equipment safety. Results will provide a basis for further study of the insulation characteristic of the C5F10O gas mixture under micro-water condition to guide the formulation of their relevant international standards prior to engineering applications.

  5. Effects of micro-water on decomposition of the environment-friendly insulating medium C5F10O

    Science.gov (United States)

    Xiao, Song; Li, Yi; Zhang, Xiaoxing; Tian, Shuangshuang; Deng, Zaitao; Tang, Ju

    2017-06-01

    SF6 is widely used in all kinds of high-voltage electrical equipment because of its excellent insulation and arc-extinguishing performance. However, this compound leads to serious greenhouse effect, which harms the environment. Many research institutions are now actively in search of SF6 alternative gas. C5F10O has attracted much attention as an alternative gas with low global warming potential (GWP) and excellent dielectric strength. In this paper, we analyzed the possible decomposition paths of C5F10O under micro-water environment through density functional theory. We also evaluated the ionization parameters and toxicity of the decomposition products. The results show that OH• and H• produced by H2O exhibited a catalytic effect on the decomposition of C5F10O. CF4, C2F6, C3F6, C3F8, C4F10, C5F12, C6F14, C3F7COH, C3F7OH, CF3COH, C3F7H, and CF3OH were produced in the micro-water environment. Based on molecular configuration calculation, the ionization parameters of these products were inferior to perfluorocarbons, such as C3F8, leading to reduced insulation performance of the system. Moreover, CF2O and HF are hazardous to human health and equipment safety. Results will provide a basis for further study of the insulation characteristic of the C5F10O gas mixture under micro-water condition to guide the formulation of their relevant international standards prior to engineering applications.

  6. 40 CFR Table C-5 to Subpart C of... - Summary of Comparability Field Testing Campaign Site and Seasonal Requirements for Class II and...

    Science.gov (United States)

    2010-07-01

    ... Campaign Site and Seasonal Requirements for Class II and III FEMs for PM10â2.5 and PM2.5 C Table C-5 to Subpart C of Part 53 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... Between Candidate Methods and Reference Methods Pt. 53, Subpt. C, Table C-5 Table C-5 to Subpart C of Part...

  7. Molecular characterization of the gerbil C5a receptor and identification of a transmembrane domain V amino acid that is crucial for small molecule antagonist interaction.

    Science.gov (United States)

    Waters, Stephen M; Brodbeck, Robbin M; Steflik, Jeremy; Yu, Jianying; Baltazar, Carolyn; Peck, Amy E; Severance, Daniel; Zhang, Lu Yan; Currie, Kevin; Chenard, Bertrand L; Hutchison, Alan J; Maynard, George; Krause, James E

    2005-12-09

    Anaphylatoxin C5a is a potent inflammatory mediator associated with pathogenesis and progression of several inflammation-associated disorders. Small molecule C5a receptor (C5aR) antagonist development is hampered by species-specific receptor biology and the associated inability to use standard rat and mouse in vivo models. Gerbil is one rodent species reportedly responsive to small molecule C5aR antagonists with human C5aR affinity. We report the identification of the gerbil C5aR cDNA using a degenerate primer PCR cloning strategy. The nucleotide sequence revealed an open reading frame encoding a 347-amino acid protein. The cloned receptor (expressed in Sf9 cells) bound recombinant human C5a with nanomolar affinity. Alignment of the gerbil C5aR sequence with those from other species showed that a Trp residue in transmembrane domain V is the only transmembrane domain amino acid unique to small molecule C5aR antagonist-responsive species (i.e. gerbil, human, and non-human primate). Site-directed mutagenesis was used to generate human and mouse C5aRs with a residue exchange of this Trp residue. Mutation of Trp to Leu in human C5aR completely eliminated small molecule antagonist-receptor interaction. In contrast, mutation of Leu to Trp in mouse C5aR enabled small molecule antagonist-receptor interaction. This crucial Trp residue is located deeper within transmembrane domain V than residues reportedly involved in C5a- and cyclic peptide C5a antagonist-receptor interaction, suggesting a novel interaction site(s) for small molecule antagonists. These data provide insight into the basis for small molecule antagonist species selectivity and further define sites critical for C5aR activation and function.

  8. Identification of a Marine Bacillus Strain C5 and Parathion-Methyl Degradation Characteristics of the Extracellular Esterase B1

    Directory of Open Access Journals (Sweden)

    Jianhua Hao

    2014-01-01

    Full Text Available A bacterial strain C5 that can produce new type of marine esterase was isolated and screened from marine sludge. According to 16S rRNA sequence analysis and physiological and biochemical experiments, the strain was identified as Bacillus subtilis. A single isozyme with a molecular weight of 86 kDa was observed by SDS-PAGE and native-PAGE. On this basis, the mechanism of esterase B1 secreted by strain C5 degrading parathion-methyl was explored, and the effects of temperature and pH on the degradation rate were investigated. From the results, p-nitrophenol was one of the degradation products of B1 degrading parathion-methyl, and the best degradation effect could be achieved at the temperature of 40°C and the neutral pH value.

  9. Roles for C-X-C chemokines and C5a in lung injury after hindlimb ischemia-reperfusion

    DEFF Research Database (Denmark)

    Bless, N M; Warner, R L; Padgaonkar, V A

    1999-01-01

    We evaluated the roles of the C-X-C chemokines cytokine-induced neutrophil chemoattractant (CINC) and macrophage inflammatory protein-2 (MIP-2) as well as the complement activation product C5a in development of lung injury after hindlimb ischemia-reperfusion in rats. During reperfusion, CD11b...... and CD18, but not CD11a, were upregulated on neutrophils [bronchoalveolar lavage (BAL) and blood] and lung macrophages. BAL levels of CINC and MIP-2 were increased during the ischemic and reperfusion periods. Treatment with either anti-CINC or anti-MIP-2 IgG significantly reduced lung vascular......, 58, and 23%, respectively (P MIP-2 as well as the complement activation product C5a are required for lung neutrophil recruitment and full induction of lung injury after hindlimb ischemia-reperfusion in rats....

  10. Resolving the contributions of the membrane-bound and periplasmic nitrate reductase systems to nitric oxide and nitrous oxide production in Salmonella enterica serovar Typhimurium.

    Science.gov (United States)

    Rowley, Gary; Hensen, Daniela; Felgate, Heather; Arkenberg, Anke; Appia-Ayme, Corinne; Prior, Karen; Harrington, Carl; Field, Sarah J; Butt, Julea N; Baggs, Elizabeth; Richardson, David J

    2012-01-15

    The production of cytotoxic nitric oxide (NO) and conversion into the neuropharmacological agent and potent greenhouse gas nitrous oxide (N₂O) is linked with anoxic nitrate catabolism by Salmonella enterica serovar Typhimurium. Salmonella can synthesize two types of nitrate reductase: a membrane-bound form (Nar) and a periplasmic form (Nap). Nitrate catabolism was studied under nitrate-rich and nitrate-limited conditions in chemostat cultures following transition from oxic to anoxic conditions. Intracellular NO production was reported qualitatively by assessing transcription of the NO-regulated genes encoding flavohaemoglobin (Hmp), flavorubredoxin (NorV) and hybrid cluster protein (Hcp). A more quantitative analysis of the extent of NO formation was gained by measuring production of N₂O, the end-product of anoxic NO-detoxification. Under nitrate-rich conditions, the nar, nap, hmp, norV and hcp genes were all induced following transition from the oxic to anoxic state, and 20% of nitrate consumed in steady-state was released as N₂O when nitrite had accumulated to millimolar levels. The kinetics of nitrate consumption, nitrite accumulation and N₂O production were similar to those of wild-type in nitrate-sufficient cultures of a nap mutant. In contrast, in a narG mutant, the steady-state rate of N₂O production was ~30-fold lower than that of the wild-type. Under nitrate-limited conditions, nap, but not nar, was up-regulated following transition from oxic to anoxic metabolism and very little N₂O production was observed. Thus a combination of nitrate-sufficiency, nitrite accumulation and an active Nar-type nitrate reductase leads to NO and thence N₂O production, and this can account for up to 20% of the nitrate catabolized.

  11. Comparative proteomic analysis of Xanthomonas citri ssp. citri periplasmic proteins reveals changes in cellular envelope metabolism during in vitro pathogenicity induction.

    Science.gov (United States)

    Artier, Juliana; da Silva Zandonadi, Flávia; de Souza Carvalho, Flávia Maria; Pauletti, Bianca Alves; Leme, Adriana Franco Paes; Carnielli, Carolina Moretto; Selistre-de-Araujo, Heloisa Sobreiro; Bertolini, Maria Célia; Ferro, Jesus Aparecido; Belasque Júnior, José; de Oliveira, Julio Cezar Franco; Novo-Mansur, Maria Teresa Marques

    2018-01-01

    Citrus canker is a plant disease caused by Gram-negative bacteria from the genus Xanthomonas. The most virulent species is Xanthomonas citri ssp. citri (XAC), which attacks a wide range of citrus hosts. Differential proteomic analysis of the periplasm-enriched fraction was performed for XAC cells grown in pathogenicity-inducing (XAM-M) and pathogenicity-non-inducing (nutrient broth) media using two-dimensional electrophoresis combined with liquid chromatography-tandem mass spectrometry. Amongst the 40 proteins identified, transglycosylase was detected in a highly abundant spot in XAC cells grown under inducing condition. Additional up-regulated proteins related to cellular envelope metabolism included glucose-1-phosphate thymidylyltransferase, dTDP-4-dehydrorhamnose-3,5-epimerase and peptidyl-prolyl cis-trans-isomerase. Phosphoglucomutase and superoxide dismutase proteins, known to be involved in pathogenicity in other Xanthomonas species or organisms, were also detected. Western blot and quantitative real-time polymerase chain reaction analyses for transglycosylase and superoxide dismutase confirmed that these proteins were up-regulated under inducing condition, consistent with the proteomic results. Multiple spots for the 60-kDa chaperonin and glyceraldehyde-3-phosphate dehydrogenase were identified, suggesting the presence of post-translational modifications. We propose that substantial alterations in cellular envelope metabolism occur during the XAC infectious process, which are related to several aspects, from defence against reactive oxygen species to exopolysaccharide synthesis. Our results provide new candidates for virulence-related proteins, whose abundance correlates with the induction of pathogenicity and virulence genes, such as hrpD6, hrpG, hrpB7, hpa1 and hrpX. The results present new potential targets against XAC to be investigated in further functional studies. © 2016 BSPP AND JOHN WILEY & SONS LTD.

  12. Effects of micro-water on decomposition of the environment-friendly insulating medium C5F10O

    OpenAIRE

    Song Xiao; Yi Li; Xiaoxing Zhang; Shuangshuang Tian; Zaitao Deng; Ju Tang

    2017-01-01

    SF6 is widely used in all kinds of high-voltage electrical equipment because of its excellent insulation and arc-extinguishing performance. However, this compound leads to serious greenhouse effect, which harms the environment. Many research institutions are now actively in search of SF6 alternative gas. C5F10O has attracted much attention as an alternative gas with low global warming potential (GWP) and excellent dielectric strength. In this paper, we analyzed the possible decomposition path...

  13. The reaction of C5N− with acetylene as a possible intermediate step to produce large anions in Titan's ionosphere

    Czech Academy of Sciences Publication Activity Database

    Lindén, F.; Žabka, Ján; Polášek, Miroslav; Zymak, Illia; Geppert, W. D.

    2018-01-01

    Roč. 20, č. 8 (2018), s. 5377-5388 ISSN 1463-9076 R&D Projects: GA MŠk(CZ) LD14024; GA ČR(CZ) GA17-14200S Grant - others:COST(XE) CM1401 Institutional support: RVO:61388955 Keywords : investigation * C5N- * Titan Subject RIV: CF - Physical ; Theoretical Chemistry OBOR OECD: Physical chemistry Impact factor: 4.123, year: 2016

  14. Targeted Delivery of Neutralizing Anti-C5 Antibody to Renal Endothelium Prevents Complement-Dependent Tissue Damage

    Directory of Open Access Journals (Sweden)

    Paolo Durigutto

    2017-09-01

    Full Text Available Complement activation is largely implicated in the pathogenesis of several clinical conditions and its therapeutic neutralization has proven effective in preventing tissue and organ damage. A problem that still needs to be solved in the therapeutic control of complement-mediated diseases is how to avoid side effects associated with chronic neutralization of the complement system, in particular, the increased risk of infections. We addressed this issue developing a strategy based on the preferential delivery of a C5 complement inhibitor to the organ involved in the pathologic process. To this end, we generated Ergidina, a neutralizing recombinant anti-C5 human antibody coupled with a cyclic-RGD peptide, with a distinctive homing property for ischemic endothelial cells and effective in controlling tissue damage in a rat model of renal ischemia/reperfusion injury (IRI. As a result of its preferential localization on renal endothelium, the molecule induced complete inhibition of complement activation at tissue level, and local protection from complement-mediated tissue damage without affecting circulating C5. The ex vivo binding of Ergidina to surgically removed kidney exposed to cold ischemia supports its therapeutic use to prevent posttransplant IRI leading to delay of graft function. Moreover, the finding that the ex vivo binding of Ergidina was not restricted to the kidney, but was also seen on ischemic heart, suggests that this RGD-targeted anti-C5 antibody may represent a useful tool to treat organs prior to transplantation. Based on this evidence, we propose preliminary data showing that Ergidina is a novel targeted drug to prevent complement activation on the endothelium of ischemic kidney.

  15. Treatment with the C5a receptor antagonist ADC-1004 reduces myocardial infarction in a porcine ischemia-reperfusion model

    Directory of Open Access Journals (Sweden)

    Arheden Håkan

    2010-09-01

    Full Text Available Abstract Background Polymorphonuclear neutrophils, stimulated by the activated complement factor C5a, have been implicated in cardiac ischemia/reperfusion injury. ADC-1004 is a competitive C5a receptor antagonist that has been shown to inhibit complement related neutrophil activation. ADC-1004 shields the neutrophils from C5a activation before they enter the reperfused area, which could be a mechanistic advantage compared to previous C5a directed reperfusion therapies. We investigated if treatment with ADC-1004, according to a clinically applicable protocol, would reduce infarct size and microvascular obstruction in a large animal myocardial infarct model. Methods In anesthetized pigs (42-53 kg, a percutaneous coronary intervention balloon was inflated in the left anterior descending artery for 40 minutes, followed by 4 hours of reperfusion. Twenty minutes after balloon inflation the pigs were randomized to an intravenous bolus administration of ADC-1004 (175 mg, n = 8 or saline (9 mg/ml, n = 8. Area at risk (AAR was evaluated by ex vivo SPECT. Infarct size and microvascular obstruction were evaluated by ex vivo MRI. The observers were blinded to the treatment at randomization and analysis. Results ADC-1004 treatment reduced infarct size by 21% (ADC-1004: 58.3 ± 3.4 vs control: 74.1 ± 2.9%AAR, p = 0.007. Microvascular obstruction was similar between the groups (ADC-1004: 2.2 ± 1.2 vs control: 5.3 ± 2.5%AAR, p = 0.23. The mean plasma concentration of ADC-1004 was 83 ± 8 nM at sacrifice. There were no significant differences between the groups with respect to heart rate, mean arterial pressure, cardiac output and blood-gas data. Conclusions ADC-1004 treatment reduces myocardial ischemia-reperfusion injury and represents a novel treatment strategy of myocardial infarct with potential clinical applicability.

  16. Deep extractive and oxidative desulfurization of dibenzothiophene with C5H9NO·SnCl2 coordinated ionic liquid.

    Science.gov (United States)

    Li, Fa-tang; Kou, Cheng-guang; Sun, Zhi-min; Hao, Ying-juan; Liu, Rui-hong; Zhao, Di-shun

    2012-02-29

    A new C5H9NO·SnCl2 coordinated ionic liquid (IL) was prepared by reacting N-methyl-pyrrolidone with anhydrous SnCl2. Desulfurization of dibenzothiophene (DBT) via extraction and oxidation with C5H9NO·SnCl2 IL as extractant, H2O2 and equal mol of CH3COOH as oxidants was investigated. The Nernst partition coefficients k(N) of C5H9NO·SnCl2 IL for the DBT in n-octane was above 5.0, showing its excellent extraction ability. During the oxidative desulfurization process, the optimal molar ratio of H2O2/DBT was six. Sulfur removal of DBT in n-octane was 94.8% in 30 min at 30 °C under the conditions of H2O2/DBT molar ratio of six and V (IL):V (oil)=1:3. Moreover, the sulfur removal increased with increasing temperature because of the high reaction rate constant, low viscosity, and high solubility of dibenzothiophene-sulfone in the IL. The kinetics of oxidative desulfurization of DBT was also investigated, and the apparent activation energy was found to be 32.5 kJ/mol. The IL could be recycled six times without a significant decrease in activity. Copyright © 2011 Elsevier B.V. All rights reserved.

  17. Receptor residence time trumps drug-likeness and oral bioavailability in determining efficacy of complement C5a antagonists

    Science.gov (United States)

    Seow, Vernon; Lim, Junxian; Cotterell, Adam J.; Yau, Mei-Kwan; Xu, Weijun; Lohman, Rink-Jan; Kok, W. Mei; Stoermer, Martin J.; Sweet, Matthew J.; Reid, Robert C.; Suen, Jacky Y.; Fairlie, David P.

    2016-04-01

    Drug discovery and translation are normally based on optimizing efficacy by increasing receptor affinity, functional potency, drug-likeness (rule-of-five compliance) and oral bioavailability. Here we demonstrate that residence time of a compound on its receptor has an overriding influence on efficacy, exemplified for antagonists of inflammatory protein complement C5a that activates immune cells and promotes disease. Three equipotent antagonists (3D53, W54011, JJ47) of inflammatory responses to C5a (3nM) were compared for drug-likeness, receptor affinity and antagonist potency in human macrophages, and anti-inflammatory efficacy in rats. Only the least drug-like antagonist (3D53) maintained potency in cells against higher C5a concentrations and had a much longer duration of action (t1/2 ~ 20 h) than W54011 or JJ47 (t1/2 ~ 1-3 h) in inhibiting macrophage responses. The unusually long residence time of 3D53 on its receptor was mechanistically probed by molecular dynamics simulations, which revealed long-lasting interactions that trap the antagonist within the receptor. Despite negligible oral bioavailability, 3D53 was much more orally efficacious than W54011 or JJ47 in preventing repeated agonist insults to induce rat paw oedema over 24 h. Thus, residence time on a receptor can trump drug-likeness in determining efficacy, even oral efficacy, of pharmacological agents.

  18. Relationship of Circulating C5a and Complement Factor H Levels With Disease Control in Pregnant Women With Asthma.

    Science.gov (United States)

    Bohács, Anikó; Bikov, András; Ivancsó, István; Czaller, Ibolya; Böcskei, Renáta; Müller, Veronika; Rigó, János; Losonczy, György; Tamási, Lilla

    2016-04-01

    Asthma often complicates pregnancy and represents a risk of serious pregnancy complications. The complement system contributes to asthma pathogenesis and is up-regulated in healthy gestation as well. The anaphylatoxin C5a has a major pro-inflammatory role, and the complement factor H is a main soluble regulator protein both in asthma and during pregnancy; however, peripheral levels of these complement factors and their relationship to disease control have not yet been evaluated in pregnant subjects with asthma. The present study aimed to investigate circulating C5a and complement factor H levels in asthma (non-pregnant subjects with asthma; n = 19) and in pregnancy with asthma (pregnant subjects with asthma; n = 22), compared with healthy non-pregnant (n = 21) and healthy pregnant women (n = 13) and to test their relationship to clinical parameters of asthma (lung function, airway inflammation, and symptoms). Circulating C5a levels were higher in the pregnant asthma subject group compared with the healthy non-pregnant, healthy pregnant, and non-pregnant asthma groups: median 2.629 (interquartile range [IQR] 2.257-3.052) ng/mL versus 1.84 (IQR 1.576-2.563), 1.783 (IQR 0.6064-2.786), and 2.024 (IQR 1.232-2.615) ng/mL, respectively (P = .02 in all cases). C5a correlated negatively with FEV1 (r = -0.44, P = .039) and FVC values (r = -0.64, P = .001) in the pregnant asthma group and positively with fraction of exhaled nitric oxide levels in the non-pregnant asthma group (n = 12, r = 0.78, P = .004). Complement factor H levels were elevated in both the healthy pregnant and pregnant asthma subject groups compared with the healthy non-pregnant group (median 1,082 [IQR 734.9-1,224] and 910.7 [IQR 614.5-1076] μg/mL vs. 559.7 [IQR 388.7-783.1] μg/mL, P = .002 and P = .004, respectively) but not in the pregnant asthma group compared with the non-pregnant asthma group (median 687.4 [IQR 441.6-947.6] μg/mL, P = .10). Asthma during pregnancy increases the circulating level of

  19. Experimental and molecular dynamics simulation study of the sublimation and vaporization energetics of iron metalocenes. crystal structures of Fe(eta5-C5H4CH3)2 and Fe[(eta5-(C5H5)(eta5-C5H4CHO)].

    Science.gov (United States)

    Lousada, Claudio M; Pinto, Susana S; Lopes, José N Canongia; da Piedade, M Fatima Minas; Diogo, Hermínio P; da Piedade, Manuel E Minas

    2008-04-03

    The standard molar enthalpies of sublimation of ferrocene, 1,1'-dimethylferrocene, decamethylferrocene, ferrocenecarboxaldehyde and alpha-methylferrocenemethanol, and the enthalpy of vaporization of N,N-dimethyl(aminomethyl)ferrocene, at 298.15 K, were determined by Calvet-drop microcalorimetry and/or the Knudsen effusion method. The obtained values were used to assess and refine our previously developed force field for metallocenes. The modified force field was able to reproduce the deltasubHdegreesm and deltavapHdegreesm values of the test-set with an accuracy better than 5 kJ.mol-1, except for decamethylferrocene, in which case the deviation between the calculated and experimental deltasubHdegreesm values was 16.1 kJ.mol-1. The origin of the larger error found in the prediction of the sublimation energetics of decamethylferrocene, and which was also observed in the estimation of structural properties (e.g., density and unit cell dimensions), is discussed. Finally, the crystal structures of Fe(eta5-C5H4CH3)2 and Fe[(eta5-(C5H5)(eta5-C5H4CHO)] at 293 and 150 K, respectively, are reported.

  20. Wave Star C5

    DEFF Research Database (Denmark)

    Kramer, Morten; Kristensen, Tom Sten

    Design pile loads in this document are based on the Morison equation. In Chapter 3 and 4 the background for the design loads provided in Chapter 5 are given. In the remaining chapters from Chapter 6 and onward discussions and explanations of the results are given. A historical list of activities ...

  1. Differential contribution of complement receptor C5aR in myeloid and non-myeloid cells in chronic ethanol-induced liver injury in mice.

    Science.gov (United States)

    McCullough, Rebecca L; McMullen, Megan R; Das, Dola; Roychowdhury, Sanjoy; Strainic, Michael G; Medof, M Edward; Nagy, Laura E

    2016-07-01

    Complement is implicated in the development of alcoholic liver disease. C3 and C5 contribute to ethanol-induced liver injury; however, the role of C5a receptor (C5aR) on myeloid and non-myeloid cells to progression of injury is not known. C57BL/6 (WT), global C5aR-/-, myeloid-specific C5aR-/-, and non-myeloid-specific C5aR-/- mice were fed a Lieber-DeCarli diet (32%kcal EtOH) for 25 days. Cultured hepatocytes were challenged with ethanol, TNFα, and C5a. Chronic ethanol feeding increased expression of pro-inflammatory mediators in livers of WT mice; this response was completely blunted in C5aR-/- mice. However, C5aR-/- mice were not protected from other measures of hepatocellular damage, including ethanol-induced increases in hepatic triglycerides, plasma alanine aminotransferase and hepatocyte apoptosis. CYP2E1 and 4-hydroxynonenal protein adducts were induced in WT and C5aR-/- mice. Myeloid-specific C5aR-/- mice were protected from ethanol-induced increases in hepatic TNFα, whereas non-myeloid-specific C5aR-/- displayed increased hepatocyte apoptosis and inflammation after chronic ethanol feeding. In cultured hepatocytes, cytotoxicity induced by challenge with ethanol and TNFα was completely eliminated by treatment with C5a in cells from WT, but not C5aR-/- mice. Further, treatment with C5a enhanced activation of pro-survival signal AKT in hepatocytes challenged with ethanol and TNFα. Taken together, these data reveal a differential role for C5aR during ethanol-induced liver inflammation and injury, with C5aR on myeloid cells contributing to ethanol-induced inflammatory cytokine expression, while non-myeloid C5aR protects hepatocytes from death after chronic ethanol feeding. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Serum cholinesterase polymorphism (CHE1 and CHE2 loci) among several Indian groups from Amazon region of Brazil, and segregation of the C5 variant in families.

    Science.gov (United States)

    Guerreiro, J F; Santos, S E; Aguiar, G F

    1989-04-01

    Eight Indian tribes from the Amazon region of Brazil (Araweté, Arara, Yamamadi, Kararaô, Karitiana, Waiampi, Surui and Cinta Larga) were studied for the distribution of the atypical and C5 variants of serum cholinesterase. None of them presented the CHE1*A allele, but the C5 variant was found in the Araweté (20.4%), Kararaô (15.6%), Karitiana (50.5%), Surui (12.3%) and Cinta Larga (19.6%) tribes. The frequency of the C5+ phenotype in the Karitiana is the highest reported thus far in human populations. Segregation studies considering the C5 variant were made among the Karitiana, and also among the Urubu-Kaapor and Munduruku tribes previously studied by Guerreiro et al [1987a, 1987b]. Most of the data were in agreement with the genetic hypothesis, but they also revealed a significant lack of the C5+ phenotype in offspring from C5+ X C5+ matings, as well as the occurrence of two C5+ children from C5- X C5- unions, in the Urubu-Kaapor tribe.

  3. Chemical conjugation of 2-hexadecynoic acid to C5-curcumin enhances its antibacterial activity against multi-drug resistant bacteria.

    Science.gov (United States)

    Sanabria-Ríos, David J; Rivera-Torres, Yaritza; Rosario, Joshua; Gutierrez, Ricardo; Torres-García, Yeireliz; Montano, Nashbly; Ortíz-Soto, Gabriela; Ríos-Olivares, Eddy; Rodríguez, José W; Carballeira, Néstor M

    2015-11-15

    The first total synthesis of a C5-curcumin-2-hexadecynoic acid (C5-Curc-2-HDA, 6) conjugate was successfully performed. Through a three-step synthetic route, conjugate 6 was obtained in 13% overall yield and tested for antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA) strains. Our results revealed that 6 was active against eight MRSA strains at MICs that range between 31.3 and 62.5 μg/mL. It was found that the presence of 2-hexadecynoic acid (2-HDA, 4) in conjugate 6 increased 4-8-fold its antibacterial activity against MRSA strains supporting our hypothesis that the chemical connection of 4 to C5-curcumin (2) increases the antibacterial activity of 2 against Gram-positive bacteria. Combinational index (CIn) values that range between 1.6 and 2.3 were obtained when eight MRSA strains were treated with an equimolar mixture of 2 and 4. These results demonstrated that an antagonistic effect is taking place. Finally, it was investigated whether conjugate 6 can affect the replication process of S. aureus, since this compound inhibited the supercoiling activity of the S. aureus DNA gyrase at minimum inhibitory concentrations (MIC) of 250 μg/mL (IC50=100.2±13.9 μg/mL). Moreover, it was observed that the presence of 4 in conjugate 6 improves the anti-topoisomerase activity of 2 towards S. aureus DNA gyrase, which is in agreement with results obtained from antibacterial susceptibility tests involving MRSA strains. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Intrathecal Spread of Injectate Following an Ultrasound-Guided Selective C5 Nerve Root Injection in a Human Cadaver Model.

    Science.gov (United States)

    Falyar, Christian R; Abercrombie, Caroline; Becker, Robert; Biddle, Chuck

    2016-04-01

    Ultrasound-guided selective C5 nerve root blocks have been described in several case reports as a safe and effective means to anesthetize the distal clavicle while maintaining innervation of the upper extremity and preserving diaphragmatic function. In this study, cadavers were injected with 5 mL of 0.5% methylene blue dye under ultrasound guidance to investigate possible proximal and distal spread of injectate along the brachial plexus, if any. Following the injections, the specimens were dissected and examined to determine the distribution of dye and the structures affected. One injection revealed dye extended proximally into the epidural space, which penetrated the dura mater and was present on the spinal cord and brainstem. Dye was noted distally to the divisions in 3 injections. The anterior scalene muscle and phrenic nerve were stained in all 4 injections. It appears unlikely that local anesthetic spread is limited to the nerve root following an ultrasound-guided selective C5 nerve root injection. Under certain conditions, intrathecal spread also appears possible, which has major patient safety implications. Additional safety measures, such as injection pressure monitoring, should be incorporated into this block, or approaches that are more distal should be considered for the acute pain management of distal clavicle fractures.

  5. Effect of short-range ordering on the electrical conductivity and superconducting properties of Nb6C5 single crystals

    International Nuclear Information System (INIS)

    Utkina, T.G.

    1995-01-01

    Niobium carbide, NbC x , belongs to the family of so called interstital phases. Metal atoms form a face-centered cubic lattice, whose octahedral interstices are occupied by carbon atoms. The fraction (1 - x) of interstices remain vacant, and this determines the nonstoichiometry of these phases: most of them are characterized by a wide homogeneity range, 0.70 m ≅ 3308 - 3886 K). In contrast, the metalloid atoms exhibit high mobility at relatively low temperatures. For compositions close to Nb 6 C 5 (0.81 O-D ≅ 1300 K. The presence of vacancies in the carbon sublattice considerably affects the physical properties of carbides, which depend not only on total vacancy concentration but also on their distribution, i.e., on the degree of ordering (both short-range and long-range order) in the metalloid sublattice. The purpose of this work is to study the effects of such ordering on the superconducting properties of Nb 6 C 5 single crystals

  6. Activation of SO2 with [(η(5) -C5 Me5 )2 Ln(THF)2 ] (Ln=Eu, Yb) leading to dithionite and sulfinate complexes.

    Science.gov (United States)

    Klementyeva, Svetlana V; Gamer, Michael T; Schmidt, Anna-Corina; Meyer, Karsten; Konchenko, Sergey N; Roesky, Peter W

    2014-10-13

    The reaction of decamethylytterbocene [(η(5) -C5 Me5 )2 Yb(THF)2 ] with SO2 at low temperature gave two new compounds, namely, the Yb(III) dithionite/sulfinate complex [{(η(5) -C5 Me5 )2 Yb(μ3 ,1κ(2) O(1,3) ,2κ(3) O(2,2',4) -S2 O4 )}2 {(η(5) -C5 Me5 )Yb(μ,1κO,2κO'-C5 Me5 SO2 )}2 ] (1) and the Yb(III) dithionite complex [{(η(5) -C5 Me5 )2 Yb}2 (μ,1κ(2) O(1,3) ,2κ(2) O(2,4) -S2 O4 )] (2). After extraction of 1, the mixture was heated to give the dinuclear tetrasulfinate complex [{(η(5) -C5 Me5 )Yb}2 (μ,κO,κO'-C5 Me5 SO2 )4 ] (3 a). In contrast, from the reaction of [(η(5) -C5 Me5 )2 Eu(THF)2 ] with SO2 only the tetrasulfinate complex [{(η(5) -C5 Me5 )Eu}2 (μ,κO,κO'-C5 Me5 SO2 )4 ] (3 b) was isolated. Two major reaction pathways were observed: 1) reductive coupling of two SO2 molecules to form the dithionite anion S2 O4 (2-) ; and 2) nucleophilic attack of one metallocene C5 Me5 ligand on the sulfur atom of SO2 . The compounds presented are the first dithionite and sulfinate complexes of the f-elements. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Structural Necessity of Indole C5-O-Substitution of seco-Duocarmycin Analogs for Their Cytotoxic Activity

    Directory of Open Access Journals (Sweden)

    Taeyoung Choi

    2010-11-01

    Full Text Available A series of racemic indole C5-O-substituted seco-cyclopropylindole (seco-CI compounds 1-5 were prepared by coupling in the presence of EDCI of 1-(tert-butyloxycarbonyl-3-(chloromethylindoline (seg-A with 5-hydroxy-, 5-O-methylsulfonyl, 5-O-aminosulfonyl, 5-O-(N,N-dimethylaminosulfonyl- and 5-O-benzyl-1H-indole-2-carboxylic acid as seg-B. Compounds 1-5 were tested for cytotoxic activity against four human cancer cell lines (COLO 205, SK-MEL-2, A549, and JEG-3 using a MTT assay. Compounds 2 and 3 with small sized sulfonyl substituents like 5-O-methylsulfonyl and 5-O-aminosulfonyl exhibit a similar level of activity as doxorubicin against all cell lines tested.

  8. A Mathematical Model for Simultaneous Saccharification and Co-fermentation (SSCF) of C6 and C5 Sugars

    DEFF Research Database (Denmark)

    Morales Rodriguez, Ricardo; Gernaey, Krist; Meyer, Anne S.

    2011-01-01

    saccharification and co-fermentation (SSCF) of C6 and C5 sugars. The model is constructed by combining existing mathematical models for enzymatic hydrolysis and co-fermentation. An inhibition of ethanol on cellulose conversion is introduced in order to increase the reliability. The mathematical model for the SSCF...... is verified by comparing the model predictions with experimental data obtained from the ethanol production based on kraft paper mill sludge. When fitting the model to the data, only the yield coefficients for glucose and xylose metabolism were fine-tuned, which were found to be 0.43 g·g−1 (ethanol....../glucose) and 0.35 g·g−1 (ethanol/xylose) respectively. These promising validation results encourage further model application to evaluate different process configurations for lignocellulosic bioethanol technology....

  9. Structure of tris(trimethylsilylcyclopentadienyl)uranium(III), [(CH3)3SiC5H43U

    International Nuclear Information System (INIS)

    Brennan, J.; Andersen, R.A.; Zalkin, A.

    1986-02-01

    Crystals of [(CH 3 ) 3 SiC 5 H 4 ] 3 U are orthorhombic, Pbca, with a = 22.630(8), b = 29.177(10) and c = 8.428(3) A at 23 0 C. For Z = 8 the calculated density is 1.551 g/cm 3 . The structure was refined by full-matrix least-squares to a conventional R factor of 0.041 [2251 data, F 2 > 2 sigma(F 2 )]. The uranium atom is bonded to the three cyclopentadienyl rings in a pentahapto fashion and is in the plane of the ring centroids. The U to ring distances are 2.54, 2.47 and 2.51 A, and the average U-C distance is 2.78 +- 0.04 A. 7 refs., 1 fig., 3 tabs

  10. A PPy-B15C5 modified lanthanum (III electrode in acetonitrile and its thermodynamic application

    Directory of Open Access Journals (Sweden)

    Mohammad Hossein Arbab Zavar

    2017-02-01

    Full Text Available Polypyrrole modified electrode prepared by electropolymerization of pyrrole in the presence of a complexing ligand, benzo-15-crown-5 (B15C5, was prepared and investigated as a La3+-selective electrode in acetonitrile. The potentiometric response of the electrode was linear within the La3+ concentration range 1 × 10−4 to 1 × 10−1 M with a Nernstian slope of 19.5 mV decade−1 in AN. The electrode was applied to study the complexation of the lanthanum (III ion in acetonitrile with other basic solvent molecules (D such as dimethyl sulfoxide, N,N-dimethylformamide, propylene carbonate, N,N,Diethylaniline and methanol. The successive complex formation constant (βi and Gibbs energies of transfer (ΔGtr of La3+ in AN in relation to such D were obtained.

  11. Conversion of C6 and C5 sugars in undetoxified wet exploded bagasse hydrolysates using Scheffersomyces (Pichia) stipitis CBS6054

    DEFF Research Database (Denmark)

    Biswas, Rajib; Uellendahl, Hinrich; Ahring, Birgitte Kiær

    2013-01-01

    Sugarcane bagasse is a potential feedstock for cellulosic ethanol production, rich in both glucan and xylan. This stresses the importance of utilizing both C6 and C5 sugars for conversion into ethanol in order to improve the process economics. During processing of the hydrolysate degradation...... products such as acetate, 5-hydroxymethylfurfural (HMF) and furfural are formed, which are known to inhibit microbial growth at higher concentrations. In the current study, conversion of both glucose and xylose sugars into ethanol in wet exploded bagasse hydrolysates was investigated without detoxification...... using Scheffersomyces (Pichia) stipitis CBS6054, a native xylose utilizing yeast strain. The sugar utilization ratio and ethanol yield (Yp/s) ranged from 88-100% and 0.33-0.41 ± 0.02 g/g, respectively, in all the hydrolysates tested. Hydrolysate after wet explosion at 185°C and 6 bar O2, composed...

  12. The new deterministic 3-D radiation transport code Multitrans: C5G7 MOX fuel assembly benchmark

    International Nuclear Information System (INIS)

    Kotiluoto, P.

    2003-01-01

    The novel deterministic three-dimensional radiation transport code MultiTrans is based on combination of the advanced tree multigrid technique and the simplified P3 (SP3) radiation transport approximation. In the tree multigrid technique, an automatic mesh refinement is performed on material surfaces. The tree multigrid is generated directly from stereo-lithography (STL) files exported by computer-aided design (CAD) systems, thus allowing an easy interface for construction and upgrading of the geometry. The deterministic MultiTrans code allows fast solution of complicated three-dimensional transport problems in detail, offering a new tool for nuclear applications in reactor physics. In order to determine the feasibility of a new code, computational benchmarks need to be carried out. In this work, MultiTrans code is tested for a seven-group three-dimensional MOX fuel assembly transport benchmark without spatial homogenization (NEA C5G7 MOX). (author)

  13. Kinetics of [14C-5] 8-methoxypsoralen uptake by UVA irradiated and non-irradiated rabbit eye tissues

    International Nuclear Information System (INIS)

    Malinin, G.I.; Glew, W.B.; Roberts, W.P.; Nigra, T.P.

    1981-01-01

    Total 8-methoxypsoralen (8-MOP) in intact and UVA irradiated rabbit eye tissues and its unaltered fraction in aqueous and eye lenses were determined over the 24 hours after i.v. injection of [ 14 C-5] and carrier 8-MOP at the concentration of 50 microCi and 5 mg/kg. No 8-MOP was detected at the end of 24 hours in intact and irradiated aqueous, vitreous and retina in contrast to one hour when the respective levels were congruent to 220, greater than 0 and congruent to 160 ng/g. Eye-plasma drug concentration ratios were less than 0.5 initially, but increased thereafter. While the average lens 8-MOP levels of congruent to 140 ng/g remained unchanged for 24 hours, no unaltered drug was detected beyond eight hours. Measurable amounts of label at the end of 24 hours also persisted in the cornea, iris, sclera and conjunctiva

  14. FecB, a periplasmic ferric-citrate transporter from E. coli, can bind different forms of ferric-citrate as well as a wide variety of metal-free and metal-loaded tricarboxylic acids.

    Science.gov (United States)

    Banerjee, Sambuddha; Paul, Subrata; Nguyen, Leonard T; Chu, Byron C H; Vogel, Hans J

    2016-01-01

    The Escherichia coli Fec system, consisting of an outer membrane receptor (FecA), a periplasmic substrate binding protein (FecB) and an inner membrane permease-ATPase type transporter (FecC/D), plays an important role in the uptake and transport of Fe(3+)-citrate. Although several FecB sequences from various organisms have been reported, there are no biophysical or structural data available for this protein to date. In this work, using isothermal titration calorimetry (ITC), we report for the first time the ability of FecB to bind different species of Fe(3+)-citrate as well as other citrate complexes with trivalent (Ga(3+), Al(3+), Sc(3+) and In(3+)) and a representative divalent metal ion (Mg(2+)) with low μM affinity. Interestingly, ITC experiments with various iron-free di- and tricarboxylic acids show that FecB can bind tricarboxylates with μM affinity but not biologically relevant dicarboxylates. The ability of FecB to bind with metal-free citrate is also observed in (1)H,(15)N HSQC-NMR titration experiments reported here at two different pH values. Further, differential scanning calorimetry (DSC) experiments indicate that the ligand-bound form of FecB has greater thermal stability than ligand-free FecB under all pH and ligand conditions tested, which is consistent with the idea of domain closure subsequent to ligand binding for this type of periplasmic binding proteins.

  15. Summertime C1-C5 alkyl nitrates over Beijing, northern China: Spatial distribution, regional transport, and formation mechanisms

    Science.gov (United States)

    Sun, Jingjing; Li, Zeyuan; Xue, Likun; Wang, Tao; Wang, Xinfeng; Gao, Jian; Nie, Wei; Simpson, Isobel J.; Gao, Rui; Blake, Donald R.; Chai, Fahe; Wang, Wenxing

    2018-05-01

    Alkyl nitrates (RONO2) are an important class of nitrogen oxides reservoirs in the atmosphere and play a key role in tropospheric photochemistry. Despite the increasing concern for photochemical air pollution over China, the knowledge of characteristics and formation mechanisms of alkyl nitrates in this region is limited. We analyzed C1-C5 alkyl nitrates measured in Beijing at a polluted urban site in summer 2008 and at a downwind rural site in summers of both 2005 and 2008. Although the abundances of NOx and hydrocarbons were much lower at the rural site, the mixing ratios of RONO2 were comparable between both sites, emphasizing the regional nature of alkyl nitrate pollution. Regional transport of urban plumes governed the elevated RONO2 levels at the rural site. The concentrations of C1-C2 RONO2 were significantly higher at the rural site in 2008 compared to 2005 despite a decline in NOx and anthropogenic VOCs, mainly owing to enhanced contributions from biogenic VOCs. The photochemical formation regimes of RONO2 were evaluated by both a simplified sequential reaction model and a detailed master chemical mechanism box model. The observed C4-C5 RONO2 levels can be well explained by the photochemical degradation of n-butane and n-pentane, while the sources of C1-C3 RONO2 were rather complex. In addition to the C1-C3 alkanes, biogenic VOCs and reactive aromatics were also important precursors of methyl nitrate, and alkenes and long-chain alkanes contributed to the formation of C2-C3 RONO2. This study provides insights into the spatial distribution, inter-annual variation and photochemical formation mechanisms of alkyl nitrate pollution over the Beijing area.

  16. Metabolic engineering for the high-yield production of isoprenoid-based C5 alcohols in E. coli

    Science.gov (United States)

    George, Kevin W.; Thompson, Mitchell G.; Kang, Aram; Baidoo, Edward; Wang, George; Chan, Leanne Jade G.; Adams, Paul D.; Petzold, Christopher J.; Keasling, Jay D.; Soon Lee, Taek

    2015-01-01

    Branched five carbon (C5) alcohols are attractive targets for microbial production due to their desirable fuel properties and importance as platform chemicals. In this study, we engineered a heterologous isoprenoid pathway in E. coli for the high-yield production of 3-methyl-3-buten-1-ol, 3-methyl-2-buten-1-ol, and 3-methyl-1-butanol, three C5 alcohols that serve as potential biofuels. We first constructed a pathway for 3-methyl-3-buten-1-ol, where metabolite profiling identified NudB, a promiscuous phosphatase, as a likely pathway bottleneck. We achieved a 60% increase in the yield of 3-methyl-3-buten-1-ol by engineering the Shine-Dalgarno sequence of nudB, which increased protein levels by 9-fold and reduced isopentenyl diphosphate (IPP) accumulation by 4-fold. To further optimize the pathway, we adjusted mevalonate kinase (MK) expression and investigated MK enzymes from alternative microbes such as Methanosarcina mazei. Next, we expressed a fusion protein of IPP isomerase and the phosphatase (Idi1~NudB) along with a reductase (NemA) to diversify production to 3-methyl-2-buten-1-ol and 3-methyl-1-butanol. Finally, we used an oleyl alcohol overlay to improve alcohol recovery, achieving final titers of 2.23 g/L of 3-methyl-3-buten-1-ol (~70% of pathway-dependent theoretical yield), 150 mg/L of 3-methyl-2-buten-1-ol, and 300 mg/L of 3-methyl-1-butanol. PMID:26052683

  17. Pro-C5, a marker of true type V collagen formation and fibrillation, correlates with portal hypertension in patients with alcoholic cirrhosis

    DEFF Research Database (Denmark)

    Leeming, Diana J; Veidal, Sanne S; Karsdal, Morten A

    2015-01-01

    Pro-C5 reflects liver hemodynamics, liver function, disease stage and clinically significant portal hypertension (PH). A multimarker model in combination with clinical scores predicted HVPG and separated clinical relevant HVPG thresholds. Plasma Pro-C5 may be suitable for the noninvasive evaluation...

  18. Optimization of hydrothermal pretreatment for co-utilization C-5 and C-6 sugars of cassava alcohol residue

    International Nuclear Information System (INIS)

    Lu, Huisheng; Lv, Chunliu; Zhang, Minhua; Liu, Shuangyan; Liu, Jiatao; Lian, Feng

    2017-01-01

    Highlights: • Cassava alcohol residue was first pretreated by hydrothermal reaction. • Hydrothermal pretreatment was optimized by RSM for co-utilization of C-5 and C-6 sugars. • The maximum xylose yield and the highest enzymatic digestibility were not obtained at the same conditions. • Optimum pretreatment conditions were at 193 °C, with 11.4% solids and for 51 min. • The optimal theoretical ethanol production was 69.5 mg/g raw materials by co-utilization of C-5 and C-6 sugars. - Abstract: Hydrothermal reaction was first applied to pretreat cassava alcohol residue for realizing the co-utilization of xylose and glucose to assume fermentation ethanol. This work focused on the influence of hydrothermal pretreatment conditions on ethanol production. Hydrothermal reaction was used to explore the maximum xylose and glucose yields, in respect to reaction temperature (120–240 °C), solid-liquid ratio (0.023–0.150) and reaction time (15–120 min). The results showed that the suitable conditions were at 180–200 °C, for 45–60 min and with 10–12.5% solids. In this range, the conjunct of xylose and glucose would reach the maximum, which can make full use of hemicellulose and cellulose in cassava alcohol residue. According to the results, respond surface methodology (RSM) based on Box-Behnken design was used to further optimize the three independent variables for the highest ethanol by co-utilization of xylose and glucose. RSM revealed that the effect of temperature on ethanol production was much more significant than the effect of reaction time and solid-liquid ratio, and the highest ethanol production was 70.6 mg/g that was close to the experiment value of 69.5 mg/g at 193 °C for 51 min and with 11.5% solids. Furthermore, the crystallinity and morphology of the untreated and pretreated cassava alcohol residue were investigated to assess the effect of hydrothermal pretreatment by scanning electron microscope (SEM) and X-ray diffraction (XRD

  19. In vitro and in vivo characteristics of a human colon cancer cell line, SNU-C5N, expressing sodium-iodide symporter

    International Nuclear Information System (INIS)

    Min, Jung-Jun; Chung, June-Key; Jin Lee, Yong; Hoon Shin, Jae; Seok Yeo, Jeong; Min Jeong, Jae; Bom, Dong Soo Leea Hee-Seung; Chul Lee, Myung

    2002-01-01

    Rat NIS (rNIS) genes were transfected into a human colon cancer cell line (SNU-C5) by lipofection. The transfected cells (SNU-C5N) exhibited an increase 125 I uptake to a level 10 times higher than the untransfected SNU-C5 cells. The addition of 300 μM DIDS, an anion channel blocker, to the culture media led to a 2.35 times increase of 125 I uptake in the cells. For the first 10 minutes, up to 70% of the cellular radioactivity was released into the medium. In the biodistribution study using SNU-C5N-xenografted mice, the %ID/g of the SNU-C5N tumors at 1, 3, 6, and 12 h after the 125 I injection were 4.43%, 1.09%, 1.05%, and 0.05%, respectively, which were significantly higher than those for the SNU-C5 tumors (P<0.05). In tumor imaging, the SNU-C5N-xenografted tumor was clearly visible. In this study, NIS lipofection is efficient for triggering significant iodide uptake by a nonthyroidal tumor. However, for an increased therapeutic effect, the key issue is iodide retention in the target tissue

  20. In vitro and in vivo characteristics of a human colon cancer cell line, SNU-C5N, expressing sodium-iodide symporter

    Energy Technology Data Exchange (ETDEWEB)

    Min, Jung-Jun; Chung, June-Key E-mail: jkchung@plaza.snu.ac.kr; Jin Lee, Yong; Hoon Shin, Jae; Seok Yeo, Jeong; Min Jeong, Jae; Bom, Dong Soo Leea Hee-Seung; Chul Lee, Myung

    2002-07-01

    Rat NIS (rNIS) genes were transfected into a human colon cancer cell line (SNU-C5) by lipofection. The transfected cells (SNU-C5N) exhibited an increase {sup 125}I uptake to a level 10 times higher than the untransfected SNU-C5 cells. The addition of 300 {mu}M DIDS, an anion channel blocker, to the culture media led to a 2.35 times increase of {sup 125}I uptake in the cells. For the first 10 minutes, up to 70% of the cellular radioactivity was released into the medium. In the biodistribution study using SNU-C5N-xenografted mice, the %ID/g of the SNU-C5N tumors at 1, 3, 6, and 12 h after the {sup 125}I injection were 4.43%, 1.09%, 1.05%, and 0.05%, respectively, which were significantly higher than those for the SNU-C5 tumors (P<0.05). In tumor imaging, the SNU-C5N-xenografted tumor was clearly visible. In this study, NIS lipofection is efficient for triggering significant iodide uptake by a nonthyroidal tumor. However, for an increased therapeutic effect, the key issue is iodide retention in the target tissue.

  1. The Crystal Structure of Cobra Venom Factor, a Cofactor for C3- and C5-Convertase CVFBb

    Energy Technology Data Exchange (ETDEWEB)

    Krishnan, Vengadesan; Ponnuraj, Karthe; Xu, Yuanyuan; Macon, Kevin; Volanakis, John E.; Narayana, Sthanam V.L.; (Madras); (UAB)

    2009-05-26

    Cobra venom factor (CVF) is a functional analog of human complement component C3b, the active fragment of C3. Similar to C3b, in human and mammalian serum, CVF binds factor B, which is then cleaved by factor D, giving rise to the CVFBb complex that targets the same scissile bond in C3 as the authentic complement convertases C4bC2a and C3bBb. Unlike the latter, CVFBb is a stable complex and an efficient C5 convertase. We solved the crystal structure of CVF, isolated from Naja naja kouthia venom, at 2.6 {angstrom} resolution. The CVF crystal structure, an intermediate between C3b and C3c, lacks the TED domain and has the CUB domain in an identical position to that seen in C3b. The similarly positioned CUB and slightly displaced C345c domains of CVF could play a vital role in the formation of C3 convertases by providing important primary binding sites for factor B.

  2. Histochemical response of `Grande naine' plants inoculated with M. fijiensis and Bacillus pumilus CCIBP-C5 cell free filtrate

    Directory of Open Access Journals (Sweden)

    Eilyn Mena

    2015-04-01

    Full Text Available In recent years, interest has won biocontrol Mycosphaerella fijiensis with the use of microorganisms or their products. Nevertheless, the knowledge of the biochemical events involved in Musa- M. fijiensis-microorganism interaction, is still limited. The objective was to determine the histochemical response of `Grande naine' (Musa AAA plants inoculated or not with the pathogen in the presence of culture filtrate of Bacillus pumilus CCIBP-C5. For this, techniques that allow visualization of callose, superoxide anion, lignin and phenolic compounds in the early days post inoculation (dpi were used. As a result, at 6 dpi callose deposition were observed within the stomata in plants where the culture filtrate was applied regardless of the presence or absence of the pathogen. Furthermore, a blue halo was observed around stomas, indicative of the presence of superoxide anion. It was not possible to detect accumulation of lignin or phenolic compounds with the technique used. It was demonstrated the accumulation of biochemical compounds related to defense response of `Grande naine' plants to pathogen infection. Furthermore, it was shown that the plant responds in early infection with the use of bacterial culture filtrates. These results demonstrate the possible mechanism of induction of defense response in plants of Musa sp. in the presence of bacterial culture filtrate. Key words: Black Sigatoka, callose, lignin, phenols, superoxide anion

  3. The behaviour of organic solvents containing C5-BTBP and CyMe4-BTBP at low irradiation doses

    International Nuclear Information System (INIS)

    Retegan, T.; Fermvik, A.; Skarnemark, G.; Foreman, M.R.S.

    2007-01-01

    Low doses of gamma radiation were given to four different solvents containing C5-BTBP and CyMe 4 -BTBP, each molecule dissolved both in cyclohexanone and hexanol. Four corresponding solvents were kept unirradiated and used as references for the extraction experiments. Multiple samples were taken from both the irradiated solutions and the reference solutions at certain time intervals. The samples were used in extraction experiments with the radionuclides 241 Am and 152 Eu. The protection against radiolysis of the extracting molecules by the diluent used for dissolution without adding a scavenger molecule was checked. The interplay between the diluent and the side group of the extracting molecule for protection against radiolysis was also studied by keeping the same type of core molecule for binding to the metal ions and varying the diluent and side group. The results were unexpected. The presence of a cyclic molecule as both a side group or diluent seems to keep the extraction of europium almost unaffected by radiolysis, while americium behaves differently from solvent to solvent. The diluent alone does not protect the extracting molecule. In some of the studied systems there is a distinct change in the extraction behaviour of Am between the irradiated and reference solutions, an effect that is however only present at the beginning of the experimental series. At later times the difference in distribution ratios between the irradiated and reference solution is constant. This phenomenon is found only when the side group and diluent are structurally dissimilar. (orig.)

  4. Photochemical Formation of C1-C5 Alkyl Nitrates in Suburban Hong Kong and over the South China Sea.

    Science.gov (United States)

    Zeng, Lewei; Lyu, Xiaopu; Guo, Hai; Zou, Shichun; Ling, Zhenhao

    2018-04-24

    Alkyl nitrates (RONO 2 ) are important reservoirs of atmospheric nitrogen, regulating nitrogen cycling and ozone (O 3 ) formation. In this study, we found that propane and n-butane were significantly lower at the offshore site (WSI) in Hong Kong ( p 0.05). Stronger oxidative capacity at WSI led to more efficient RONO 2 formation. Relative incremental reactivity (RIR) was for the first time used to evaluate RONO 2 -precursor relationships. In contrast to a consistently volatile organic compounds (VOC)-limited regime at TC, RONO 2 formation at WSI switched from VOC-limited regime during O 3 episodes to VOC and nitrogen oxides (NO x ) colimited regime during nonepisodes. Furthermore, unlike the predominant contributions of parent hydrocarbons to C 4 -C 5 RONO 2 , the production of C 1 -C 3 RONO 2 was more sensitive to other VOCs like aromatics and carbonyls, which accounted for ∼40-90% of the productions of C 1 -C 3 alkylperoxy (RO 2 ) and alkoxy radicals (RO) at both sites. This resulted from the decomposition of larger RO 2 /RO and the change of OH abundance under the photochemistry of other VOCs. This study advanced our understanding of the photochemical formation of RONO 2 , particularly the relationships between RONO 2 and their precursors, which were not confined to the parent hydrocarbons.

  5. Results of postirradiation examination of the in-pile blockage experiments MOL-7C/4 and MOL-7C/5

    International Nuclear Information System (INIS)

    Weimar, P.; Schleisiek, K.

    1991-01-01

    The Mol-7C in-pile local blockage experiments are performed in the BR-2 reactor at Mol, Belgium as a joint project of Kernforchungszentrum Karlsruhe (KfK) and Studiecentrum voor Kernenergie/Centre d'Etude de l'Energie Nuclearire-Mol. The main objective is to investigate the consequences of local cooling disturbances in liquid-metal-cooled reactor (LMR) fuel subassemblies. In the tests Mol-7C/4 and MOL-7C/5, fuel pins from KNK II are used with a burnup of 5 and 1.7%, respectively. An active central porous blockage is used to simulate the cooling disturbance. During irradiation, the blockage causes significant local damage, including melting of cladding and fuel. Extensive postirradiation examinations (PIE) are performed to investigate the extent of damage. In this paper a description and interpretation of results of the destructive PIE performed at the Hot Cells Laboratory at KfK is given, along with some conclusions related to LMR safety

  6. Polar localization of PhoN2, a periplasmic virulence-associated factor of Shigella flexneri, is required for proper IcsA exposition at the old bacterial pole.

    Directory of Open Access Journals (Sweden)

    Daniela Scribano

    Full Text Available Proper protein localization is critical for bacterial virulence. PhoN2 is a virulence-associated ATP-diphosphohydrolase (apyrase involved in IcsA-mediated actin-based motility of S. flexneri. Herein, by analyzing a ΔphoN2 mutant of the S. flexneri strain M90T and by generating phoN2::HA fusions, we show that PhoN2, is a periplasmic protein that strictly localizes at the bacterial poles, with a strong preference for the old pole, the pole where IcsA is exposed, and that it is required for proper IcsA exposition. PhoN2-HA was found to be polarly localized both when phoN2::HA was ectopically expressed in a Escherichia coli K-12 strain and in a S. flexneri virulence plasmid-cured mutant, indicating a conserved mechanism of PhoN2 polar delivery across species and that neither IcsA nor the expression of other virulence-plasmid encoded genes are involved in this process. To assess whether PhoN2 and IcsA may interact, two-hybrid and cross-linking experiments were performed. While no evidence was found of a PhoN2-IcsA interaction, unexpectedly the outer membrane protein A (OmpA was shown to bind PhoN2-HA through its periplasmic-exposed C-terminal domain. Therefore, to identify PhoN2 domains involved in its periplasmic polar delivery as well as in the interaction with OmpA, a deletion and a set of specific amino acid substitutions were generated. Analysis of these mutants indicated that neither the (183PAPAP(187 motif of OmpA, nor the N-terminal polyproline (43PPPP(46 motif and the Y155 residue of PhoN2 are involved in this interaction while P45, P46 and Y155 residues were found to be critical for the correct folding and stability of the protein. The relative rapid degradation of these amino acid-substituted recombinant proteins was found to be due to unknown S. flexneri-specific protease(s. A model depicting how the PhoN2-OmpA interaction may contribute to proper polar IcsA exposition in S. flexneri is presented.

  7. Polar localization of PhoN2, a periplasmic virulence-associated factor of Shigella flexneri, is required for proper IcsA exposition at the old bacterial pole.

    Science.gov (United States)

    Scribano, Daniela; Petrucca, Andrea; Pompili, Monica; Ambrosi, Cecilia; Bruni, Elena; Zagaglia, Carlo; Prosseda, Gianni; Nencioni, Lucia; Casalino, Mariassunta; Polticelli, Fabio; Nicoletti, Mauro

    2014-01-01

    Proper protein localization is critical for bacterial virulence. PhoN2 is a virulence-associated ATP-diphosphohydrolase (apyrase) involved in IcsA-mediated actin-based motility of S. flexneri. Herein, by analyzing a ΔphoN2 mutant of the S. flexneri strain M90T and by generating phoN2::HA fusions, we show that PhoN2, is a periplasmic protein that strictly localizes at the bacterial poles, with a strong preference for the old pole, the pole where IcsA is exposed, and that it is required for proper IcsA exposition. PhoN2-HA was found to be polarly localized both when phoN2::HA was ectopically expressed in a Escherichia coli K-12 strain and in a S. flexneri virulence plasmid-cured mutant, indicating a conserved mechanism of PhoN2 polar delivery across species and that neither IcsA nor the expression of other virulence-plasmid encoded genes are involved in this process. To assess whether PhoN2 and IcsA may interact, two-hybrid and cross-linking experiments were performed. While no evidence was found of a PhoN2-IcsA interaction, unexpectedly the outer membrane protein A (OmpA) was shown to bind PhoN2-HA through its periplasmic-exposed C-terminal domain. Therefore, to identify PhoN2 domains involved in its periplasmic polar delivery as well as in the interaction with OmpA, a deletion and a set of specific amino acid substitutions were generated. Analysis of these mutants indicated that neither the (183)PAPAP(187) motif of OmpA, nor the N-terminal polyproline (43)PPPP(46) motif and the Y155 residue of PhoN2 are involved in this interaction while P45, P46 and Y155 residues were found to be critical for the correct folding and stability of the protein. The relative rapid degradation of these amino acid-substituted recombinant proteins was found to be due to unknown S. flexneri-specific protease(s). A model depicting how the PhoN2-OmpA interaction may contribute to proper polar IcsA exposition in S. flexneri is presented.

  8. Paleontology and stratigraphy of the Upper Triassic Kamishak Formation in the Puale Bay-Cape Kekurnoi-Alinchak Bay area, Karluk C-4 and C-5 quadrangle

    Data.gov (United States)

    Department of the Interior — This report summarizes the paleontological character and stratigraphy of the Kamishak Formation in the Puale Bay–Cape Kekurnoi–Alinchak Bay area, Karluk C-4 and C-5...

  9. The comparison of MODIS-Aqua (C5 and CALIOP (V2 & V3 aerosol optical depth

    Directory of Open Access Journals (Sweden)

    J. Redemann

    2012-03-01

    Full Text Available We assess the consistency between instantaneously collocated level-2 aerosol optical depth (AOD retrievals from MODIS-Aqua (C5 and CALIOP (Version 2 & 3, comparing the standard MODIS AOD (MYD04_L2 data to the AOD calculated from CALIOP aerosol extinction profiles for both the previous release (V2 and the latest release (V3 of CALIOP data. Based on data collected in January 2007, we investigate the most useful criteria for screening the MODIS and CALIOP retrievals to achieve the best agreement between the two data sets. Applying these criteria to eight months of data (Jan, Apr, Jul, Oct 2007 and 2009, we find an order of magnitude increase for the CALIOP V3 data density (by comparison to V2, that is generally accompanied by equal or better agreement with MODIS AOD. Differences in global, monthly mean, over-ocean AOD (532 nm between CALIOP and MODIS range between 0.03 and 0.04 for CALIOP V3, with CALIOP generally biased low, when all available data from both sensors are considered. Root-mean-squares (RMS differences in instantaneously collocated AOD retrievals by the two instruments are reduced from values ranging between 0.14 and 0.19 using the unscreened V3 data to values ranging from 0.09 to 0.1 for the screened data. A restriction to scenes with cloud fractions less than 1% (as defined in the MODIS aerosol retrievals generally results in improved correlation (R2>0.5, except for the month of July when correlations remain relatively lower. Regional assessments show hot spots in disagreement between the two sensors in Asian outflow during April and off the coast of South Africa in July.

  10. Geologic Emissions of Methane and C2 - C5 Alkanes at the La Brea Tar Pits, Los Angeles, CA

    Science.gov (United States)

    Doezema, L. A.; Etiope, G.; Pacheco, C.

    2017-12-01

    Natural hydrocarbon (oil and gas) seeps are widespread in Los Angeles due to gas migration, along faults, from numerous subsurface petroleum fields. These seeps may represent important natural contributors of methane (CH4) and heavier alkanes (C2-C4) for the atmosphere. Methane flux measurements were made from various locations at the La Brea Tar Pits in Los Angeles, CA. Measurements were made using a closed-chamber method and spectroscopic sensors for CH4 and CO2, at 26 oil-asphalt seeps and 188 other sites, without gas manifestations, homogeneously distributed throughout the park. The molecular C1 - C5 composition of gas released from seeps and soil was also analyzed using either FTIR spectroscopy or gas chromatography (GC-FID). Methane emissions from seeps varied from approximately 7 to 54,000 g m-2 day-1, while emissions from soil degassing were between 0 and 9,000 g m-2 day-1. Total emissions were estimated to be in the order of 103 kg day-1 for methane, and at least 10 and 5 kg day-1 for ethane and propane, respectively. The seeping gas exhibited high C1/(C2 + C3) ratios, likely due to molecular fractionation during gas migration from a subsurface petroleum reservoir. Evidence for biodegredation in certain samples was indicated by large i-butane to n-butane ratios. These molecular alterations can be important tracers of natural seepage and should be considered in the atmospheric modelling of the relative contribution of fossil fuel (anthropogenic fugitive emission and natural geologic sources) vs biogenic sources, on local and global scales.

  11. Standard Molar Enthalpy of Formation of RE(C5H8NS2)3(o-phen)

    Institute of Scientific and Technical Information of China (English)

    MENG Xiang-Xin; GAO Sheng-Li; CHEN San-Ping; YANG Xu-Wu; XIE Gang; SHI Qi-Zhen

    2005-01-01

    Five solid ternary complexes of RE(C5H8NS2)3(o-phen) (RE=Ho, Er, Tm, Yb, Lu) have been synthesized in absolute ethanol by rare earth chloride low hydrate reacting with the mixed ligands of ammonium pyrrolidinedithiocarbamate (APDC) and 1,10-phenanthroline·H2O (o-phen·H2O) in the ordinary laboratory atmosphere without any cautions against moisture or air. IR spectra of the complexes showed that the RE3+ coordinated with six sulfur atoms of three PDC- and two nitrogen atoms of o-phen·H2O. It was assumed that the coordination number of RE3+was eight. The constant-volume combustion energies of the complexes, △cU, were determined as (-16788.46±7.74), (- 15434.53± 8.28), (- 15287.807.31), (- 15200.50±7.22) and (- 15254.34±6.61) kJ·mol-1, respectively, by a precise rotating-bomb calorimeter at 298.15 K. Its standard molar enthalpies of combustion, △cH m,and standard molar enthalpies of formation, △fH m, were calculated as (-16803.95 ±7.74), (-15450.02±8.28),(-15303.29±9.28), (-15215.99±7.22), (-15269.83±6.61) kJ·mol-1 and (-1115.42±8.94), (-2477.80±9.15), (-2619.95 ±10.44), (-2670.17 ± 8.22), ( -2650.06± 8.49) kJ·mol-1, respectively.

  12. Kinetic study of the degradation of C5 and C6 unsaturated aldehydes and alcohols by ozone

    Science.gov (United States)

    Kalalian, Carmen; Roth, Estelle; Chakir, Abdelkhaleq

    2017-04-01

    Emissions of biogenic volatile organic compounds (VOCs) are higher than those from anthropogenic sources. They are therefore likely to have a great influence on atmospheric chemistry both locally and regionally, through their impact on the HOx balance (HOx = HO + HO2), ozone production and ability to form secondary organic aerosols (SOA). Among the volatile organic compounds of biogenic origin are the family of C5 and C6 unsaturated aldehydes and alcohols. Few information exist regarding the fate of these compounds in the atmosphere especially there reaction with ozone. In this work, we studied the kinetics of the reaction of three unsaturated aldehydes (trans-2-pentenal, trans-2-hexenal and 2-methyl-2-pentenal) and three unsaturated alcohols (1-penten-3-ol, cis-2-penten-1-ol and trans-3-hexen-1-ol) with ozone O3 in a rigid atmospheric simulation chamber coupled to an FTIR spectrometer at four different temperatures (273, 298, 333 and 353 K) and at atmospheric pressure. The rate constants of the ozonolysis reaction of the unsaturated aldehydes and the unsaturated alcohols studied were determined and the following Arrhenius expression was obtained (cm3 molecule -1 s -1): k (Trans -2-pentenal)= (3.83 ± 3.71) x 10-16 exp (- (1706 ± 295) / T) k (Trans-2-hexenal)= (1.43 ± 0.67) x 10-16 exp (- (1369 ± 141) / T) k(2-Methyl-2-pentenal)= (3.62± 0.22) x 10-18 exp (- (121 ± 20) / T) k(1-penten-3-ol) = (1.42 ± 1.24) x 10-16 exp (- (642 ± 250) / T) k(Cis-2-penten-1-ol)= (3.14 ± 0.45) x 10-15 exp (- (1045 ± 40) / T) k(Trans-3-hexen-1-ol)= (6.38 ± 1.75) x 10-16 exp (- (686 ± 89) / T) The obtained data will be discussed in terms of structure-reactivity relationship and compared with the reported reactivity with OH radicals. The atmospheric implications derived from this study are discussed as well.

  13. Effects of the η(5)-C5H4(i)Pr Ligand on the Properties Exhibited by Its Tungsten Nitrosyl Complexes.

    Science.gov (United States)

    Fabulyak, Diana; Baillie, Rhett A; Patrick, Brian O; Legzdins, Peter; Rosenfeld, Devon C

    2016-02-15

    Reaction of Na[η(5)-C5H4(i)Pr] with W(CO)6 in refluxing THF for 4 days generates a solution of Na[(η(5)-C5H4(i)Pr)W(CO)3] that when treated with N-methyl-N-nitroso-p-toluenesulfonamide at ambient temperatures affords (η(5)-C5H4(i)Pr)W(NO)(CO)2 (1) that is isolable in good yield as an analytically pure orange oil. Treatment of 1 with an equimolar amount of I2 in Et2O at ambient temperatures affords (η(5)-C5H4(i)Pr)W(NO)I2 (2) as a dark brown solid in excellent yield. Sequential treatment at low temperatures of 2 with 0.5 equiv of Mg(CH2CMe3)2 and Mg(CH2CH═CMe2)2 in Et2O produces the alkyl allyl complex, (η(5)-C5H4(i)Pr)W(NO)(CH2CMe3)(η(3)-CH2CHCMe2) (3), as a thermally sensitive yellow liquid. Complex 3 may also be synthesized, albeit in low yield, in one vessel at low temperatures by reacting 1 first with 1 equiv of PCl5 and then with the binary magnesium reagents specified above. Interestingly, similar treatment of 1 in Et2O with PCl5 and only 0.5 equiv of Mg(CH2CH═CMe2)2 results in the formation of the unusual complex (η(5)-C5H4(i)Pr)W(NO)(PCl2CMe2CH═CH2)Cl2 (4), which probably is formed via a metathesis reaction of the binary magnesium reagent with (η(5)-C5H4(i)Pr)W(NO)(PCl3)Cl2. The C-D activation of C6D6 by complex 3 has been investigated and compared to that exhibited by its η(5)-C5Me5, η(5)-C5Me4H, and η(5)-C5Me4(n)Pr analogues. Kinetic analyses of the various activations have established that the presence of the η(5)-C5H4(i)Pr ligand significantly increases the rate of the reaction, an outcome that can be attributed to a combination of steric and electronic factors. In addition, mechanistic studies have established that in solution 3 loses neopentane under ambient conditions to generate exclusively the 16e η(2)-diene intermediate complex (η(5)-C5H4(i)Pr)W(NO)(η(2)-CH2═CMeCH═CH2), which then effects the subsequent C-D activations. This behavior contrasts with that exhibited by the η(5)-C5Me5 analogue of 3 which forms both η(2

  14. Deletion of the complement C5a receptor alleviates the severity of acute pneumococcal otitis media following influenza A virus infection in mice.

    Directory of Open Access Journals (Sweden)

    Hua Hua Tong

    Full Text Available There is considerable evidence that influenza A virus (IAV promotes adherence, colonization, and superinfection by S. pneumoniae (Spn and contributes to the pathogenesis of otitis media (OM. The complement system is a critical innate immune defense against both pathogens. To assess the role of the complement system in the host defense and the pathogenesis of acute pneumococcal OM following IAV infection, we employed a well-established transtympanically-induced mouse model of acute pneumococcal OM. We found that antecedent IAV infection enhanced the severity of acute pneumococcal OM. Mice deficient in complement C1qa (C1qa-/- or factor B (Bf -/- exhibited delayed viral and bacterial clearance from the middle ear and developed significant mucosal damage in the eustachian tube and middle ear. This indicates that both the classical and alternative complement pathways are critical for the oto-immune defense against acute pneumococcal OM following influenza infection. We also found that Spn increased complement activation following IAV infection. This was characterized by sustained increased levels of anaphylatoxins C3a and C5a in serum and middle ear lavage samples. In contrast, mice deficient in the complement C5a receptor (C5aR demonstrated enhanced bacterial clearance and reduced severity of OM. Our data support the concept that C5a-C5aR interactions play a significant role in the pathogenesis of acute pneumococcal OM following IAV infection. It is possible that targeting the C5a-C5aR axis might prove useful in attenuating acute pneumococcal OM in patients with influenza infection.

  15. Classification and Progression Based on CFS-GA and C5.0 Boost Decision Tree of TCM Zheng in Chronic Hepatitis B.

    Science.gov (United States)

    Chen, Xiao Yu; Ma, Li Zhuang; Chu, Na; Zhou, Min; Hu, Yiyang

    2013-01-01

    Chronic hepatitis B (CHB) is a serious public health problem, and Traditional Chinese Medicine (TCM) plays an important role in the control and treatment for CHB. In the treatment of TCM, zheng discrimination is the most important step. In this paper, an approach based on CFS-GA (Correlation based Feature Selection and Genetic Algorithm) and C5.0 boost decision tree is used for zheng classification and progression in the TCM treatment of CHB. The CFS-GA performs better than the typical method of CFS. By CFS-GA, the acquired attribute subset is classified by C5.0 boost decision tree for TCM zheng classification of CHB, and C5.0 decision tree outperforms two typical decision trees of NBTree and REPTree on CFS-GA, CFS, and nonselection in comparison. Based on the critical indicators from C5.0 decision tree, important lab indicators in zheng progression are obtained by the method of stepwise discriminant analysis for expressing TCM zhengs in CHB, and alterations of the important indicators are also analyzed in zheng progression. In conclusion, all the three decision trees perform better on CFS-GA than on CFS and nonselection, and C5.0 decision tree outperforms the two typical decision trees both on attribute selection and nonselection.

  16. c-C5H5 on a Ni(1 1 1) surface: Theoretical study of the adsorption, electronic structure and bonding

    International Nuclear Information System (INIS)

    German, E.; Simonetti, S.; Pronsato, E.; Juan, A.; Brizuela, G.

    2008-01-01

    In the present work the ASED-MO method is applied to study the adsorption of cyclopentadienyl anion on a Ni(1 1 1) surface. The adsorption with the centre of the aromatic ring placed above the hollow position has been identified to be energetically the most favourable. The aromatic ring remains almost flat, the H atoms are tilted 17 deg. away from the metal surface. We modelled the metal surface by a two-dimensional slab of finite thickness, with an overlayer of c-C 5 H 5 - , one c-C 5 H 5 - per nine surface Ni atoms. The c-C 5 H 5 - molecule is attached to the surface with its five C atoms bonding mainly with three Ni atoms. The Ni-Ni bond in the underlying surface and the C-C bonds of c-C 5 H 5 - are weakened upon adsorption. We found that the band of Ni 5d z 2 orbitals plays an important role in the bonding between c-C 5 H 5 - and the surface, as do the Ni 6s and 6p z bands

  17. Etching Enhancement Followed by Nitridation on Low-k SiOCH Film in Ar/C5F10O Plasma

    Science.gov (United States)

    Miyawaki, Yudai; Shibata, Emi; Kondo, Yusuke; Takeda, Keigo; Kondo, Hiroki; Ishikawa, Kenji; Okamoto, Hidekazu; Sekine, Makoto; Hori, Masaru

    2013-02-01

    The etching rates of low-dielectric-constant (low-k), porous SiOCH (p-SiOCH) films were increased by nitrogen-added Ar/C5F10O plasma etching in dual-frequency (60 MHz/2 MHz)-excited parallel plate capacitively coupled plasma. Previously, perfluoropropyl vinyl ether [C5F10O] provided a very high density of CF3+ ions [Nagai et al.: Jpn. J. Appl. Phys. 45 (2006) 7100]. Surface nitridation on the p-SiOCH surface exposed to Ar/N2 plasma led to the etching of larger amounts of p-SiOCH in Ar/C5F10O plasma, which depended on the formation of bonds such as =C(sp2)=N(sp2)- and -C(sp)≡N(sp).

  18. Complement component C5a Promotes Expression of IL-22 and IL-17 from Human T cells and its Implication in Age-related Macular Degeneration

    Directory of Open Access Journals (Sweden)

    Klein Michael L

    2011-07-01

    Full Text Available Abstract Background Age related macular degeneration (AMD is the leading cause of irreversible blindness in elderly populations worldwide. Inflammation, among many factors, has been suggested to play an important role in AMD pathogenesis. Recent studies have demonstrated a strong genetic association between AMD and complement factor H (CFH, the down-regulatory factor of complement activation. Elevated levels of complement activating molecules including complement component 5a (C5a have been found in the serum of AMD patients. Our aim is to study whether C5a can impact human T cells and its implication in AMD. Methods Human peripheral blood mononuclear cells (PBMCs were isolated from the blood of exudative form of AMD patients using a Ficoll gradient centrifugation protocol. Intracellular staining and enzyme-linked immunosorbent assays were used to measure protein expression. Apoptotic cells were detected by staining of cells with the annexin-V and TUNEL technology and analyzed by a FACS Caliber flow cytometer. SNP genotyping was analyzed by TaqMan genotyping assay using the Real-time PCR system 7500. Results We show that C5a promotes interleukin (IL-22 and IL-17 expression by human CD4+ T cells. This effect is dependent on B7, IL-1β and IL-6 expression from monocytes. We have also found that C5a could protect human CD4+ cells from undergoing apoptosis. Importantly, consistent with a role of C5a in promoting IL-22 and IL-17 expression, significant elevation in IL-22 and IL-17 levels was found in AMD patients as compared to non-AMD controls. Conclusions Our results support the notion that C5a may be one of the factors contributing to the elevated serum IL-22 and IL-17 levels in AMD patients. The possible involvement of IL-22 and IL-17 in the inflammation that contributes to AMD may herald a new approach to treat AMD.

  19. Low-k SiOCH Film Etching Process and Its Diagnostics Employing Ar/C5F10O/N2 Plasma

    Science.gov (United States)

    Nagai, Mikio; Hayashi, Takayuki; Hori, Masaru; Okamoto, Hidekazu

    2006-09-01

    We proposed an environmental harmonic etching gas of C5F10O (CF3CF2CF2OCFCF2), and demonstrated the etching of low-k SiOCH films employing a dual-frequency capacitively coupled etching system. Dissociative ionization cross sections for the electron impact ionizations of C5F10O and c-C4F8 gases have been measured by quadrupole mass spectroscopy (QMS). The dissociative ionization cross section of CF3+ from C5F10O gas was much higher than those of other ionic species, and 10 times higher than that of CF3+ from C4F8 gas. CF3+ is effective for increasing the etching rate of SiO2. As a result, the etching rate of SiOCH films using Ar/C5F10O/N2 plasma was about 1000 nm/min, which is much higher than that using Ar/C4F8/N2 plasma. The behaviours of fluorocarbon radicals in Ar/C5F10O/N2 plasma, which were measured by infrared diode laser absorption spectroscopy, were similar to those in Ar/C4F8/N2 plasma. The densities of CF and CF3 radicals were markedly decreased with increasing N2 flow rate. Etching rate was controlled by N2 flow rate. A vertical profile of SiOCH with a high etching rate and less microloading was realized using Ar/C5F10O/N2 plasma chemistry.

  20. Evolution and estimated age of the C5 Lukala carbonate-evaporite ramp complex in the Lower Congo region (Democratic Republic of Congo): New perspectives in Central Africa

    Science.gov (United States)

    Delpomdor, F.; Van Vliet, N.; Devleeschouwer, X.; Tack, L.; Préat, A.

    2018-01-01

    New detailed lithological, sedimentological, chemostratigraphic data were obtained from exploration drilling samples on the C5 carbonate-dominated formation of the Neoproterozoic Lukala Subgroup (former Schisto-Calcaire Subgroup) from the West Congo Belt (WCB) in the Democratic Republic of Congo. This formation records the last post-Marinoan sea-level events that occurred in the whole basin, followed by the development of the Araçuaï-West Congo Orogen between 630 and 560 Ma. The C5 Formation consists of back-reef lagoonal and peritidal/sabkha cycles of ∼2.0 m in thickness, that record a short-time marine regression, rapidly flooded by a marine transgression with deposition of organic-rich argillaceous carbonates or shales under dysoxia and anoxia conditions. These dysoxic/anoxic waters were rapidly followed by a regional-scale marine transgression, favouring mixing with well-oxygenated waters, and the development of benthic Tonian to Cambro-Ordovician Obruchevella parva-type 'seagrasses' in the nearshore zones of the lagoons. New δ13C and 87Sr/86Sr isotopic data in the C5 Formation of the Lukala Subgroup are used in the frame of a correlation with the Sete Lagoas Formation in Brazil. Relatively comparable negative to positive δ13C excursions point to marine flooding of the whole basin and allow extension of the debatable Late Ediacaran age of the uppermost Sete Lagoas and C5 formations. Sr isotope ;blind dating; failed due to low Sr concentration related to a dolomitization event close 540 Ma. Several tentative datings of the C5 Formation converge to a Late Ediacaran age ranging between 575 and 540 Ma. As the overlying Mpioka folded Subgroup, the C5 series suffered the Pan African deformation, dated at 566 ± 42 Ma. Unlike the previously generally accepted interpretation, our data suggests that the Mpioka Subgroup was deposited in the Early Cambrian.

  1. Relative bioavailability of 13C5-folic acid in pectin-coated folate fortified rice in humans using stable isotope techniques.

    Science.gov (United States)

    de Ambrosis, A; Vishnumohan, S; Paterson, J; Haber, P; Arcot, J

    2017-01-01

    The aim of the study was to measure the relative bioavailability of labeled pteroylglutamic acid (13C5-PteGlu) from a pectin-coated fortified rice in vivo to measure any effect of the edible coating on folic acid bioavailability. Healthy volunteers (N=26) aged 18-39 years received three test meals in three randomized short-term cross-over trials: Trial 1: aqueous 400 μg 13C5-PteGlu, Trial 2: 200 g cooked white rice+400 μg 13C5-PteGlu,Trial 3: 200 g fortified cooked white rice with pectin-coated premix containing 400 μg 13C5-PteGlu. Blood samples were drawn at 0,1,2,5 and 8 h postprandial. The concentration of 13C5-5 methyl-tetrahydrofolate appearing in plasma was quantified using high performance liquid chromatography-mass spectrometry (MS)/MS. For 24 h before baseline estimation and during the area under the curve (AUC) study, the subjects were placed on a low folate diet (∼100 μg/day). The relative bioavailability of the folic acid following Trial 3 was measured by comparing the 13C5-5 methyl-tetrahydrofuran (THF) AUC with Trials 1 and 2. The bioavailability of folic acid in a pectin-coated rice premix was 68.7% (range 47-105) and 86.5% (range 65-115) in uncoated fortified rice relative to aqueous folic acid. This study is the first demonstration of the bioavailability of folate in pectin-coated fortified rice in humans.

  2. Total Synthesis of Zoanthamine Alkaloids, Part 2. Construction of the C1-C5, C6-C10 and C11-C24 Fragments of Zoanthamine

    DEFF Research Database (Denmark)

    Tanner, David Ackland; Tedenborg, Lars; Somfai, Peter

    1997-01-01

    This paper describes the construction of three key intermediates for a projected total synthesis of the marine alkaloid zoanthamine. These building blocks, corresponding to the C1-C5, C6-C10 and C11-C24 fragments of the target molecule, are synthesised efficiently form (R)-hydroxymethyl-butyrolac......This paper describes the construction of three key intermediates for a projected total synthesis of the marine alkaloid zoanthamine. These building blocks, corresponding to the C1-C5, C6-C10 and C11-C24 fragments of the target molecule, are synthesised efficiently form (R...

  3. From laboratory catalysts to a new prototype: a novel real candidate for the isomerization of C5–C6 paraffins

    Czech Academy of Sciences Publication Activity Database

    Hidalgo, J. M.; Kaucký, Dalibor; Bortnovsky, O.; Černý, R.; Sobalík, Zdeněk

    2015-01-01

    Roč. 5, JUN 2015 (2015), s. 56625-56628 ISSN 2046-2069 R&D Projects: GA MPO FR-TI3/316 Institutional support: RVO:61388955 Keywords : C5-C6 paraffins * isomeration * Pt/WO3–ZrO2 materials Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.289, year: 2015

  4. Systems biology and pathway engineering enable Saccharomyces cerevisiae to utilize C-5 and C-6 sugars simultaneously for cellulosic ethanol production

    Science.gov (United States)

    Saccharomyces cerevisiae is a traditional industrial workhorse for ethanol production. However, conventional ethanologenic yeast is superior in fermentation of hexose sugars (C-6) such as glucose but unable to utilize pentose sugars (C-5) such as xylose richly embedded in lignocellulosic biomass. In...

  5. Total Synthesis of Zoanthamine Alkaloids, Part 2. Construction of the C1-C5, C6-C10 and C11-C24 Fragments of Zoanthamine

    DEFF Research Database (Denmark)

    Tanner, David Ackland; Tedenborg, Lars; Somfai, Peter

    1997-01-01

    This paper describes the construction of three key intermediates for a projected total synthesis of the marine alkaloid zoanthamine. These building blocks, corresponding to the C1-C5, C6-C10 and C11-C24 fragments of the target molecule, are synthesised efficiently form (R...

  6. Neuroimaging findings in Joubert syndrome with C5orf42 gene mutations: A milder form of molar tooth sign and vermian hypoplasia.

    Science.gov (United States)

    Enokizono, Mikako; Aida, Noriko; Niwa, Tetsu; Osaka, Hitoshi; Naruto, Takuya; Kurosawa, Kenji; Ohba, Chihiro; Suzuki, Toshifumi; Saitsu, Hirotomo; Goto, Tomohide; Matsumoto, Naomichi

    2017-05-15

    Little is known regarding neuroimaging-genotype correlations in Joubert syndrome (JBTS). To elucidate one of these correlations, we investigated the neuroimaging findings of JBTS patients with C5orf42 mutations. Neuroimaging findings in five JBTS patients with C5orf42 mutations were retrospectively assessed with regard to the infratentorial and supratentorial structures on T1-magnetization prepared rapid gradient echo (MPRAGE), T2-weighted images, and color-coded fractional anisotropy (FA) maps; the findings were compared to those in four JBTS patients with mutations in other genes (including three with AHI1 and one with TMEM67 mutations). In C5orf42-mutant patients, the infratentorial magnetic resonance (MR) images showed normal or minimally thickened and minimally elongated superior cerebellar peduncles (SCP), normal or minimally deepened interpeduncular fossa (IF), and mild vermian hypoplasia (VH). However, in other patients, all had severe abnormalities in the SCP and IF, and moderate to marked VH. Supratentorial abnormalities were found in one individual in other JBTS. In JBTS with all mutations, color-coded FA maps showed the absence of decussation of the SCP (DSCP). The morphological neuroimaging findings in C5orf42-mutant JBTS were distinctly mild and made diagnosis difficult. However, the absence of DSCP on color-coded FA maps may facilitate the diagnosis of JBTS. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Treatment with anti-C5aR mAb leads to early-onset clinical and mechanistic effects in the murine delayed-type hypersensitivity arthritis model

    DEFF Research Database (Denmark)

    Atkinson, Sara Marie; Nansen, Anneline; Usher, Pernille A.

    2015-01-01

    Blockade of the complement cascade at the C5a/C5a receptor (C5aR)-axis is believed to be an attractive treatment avenue in rheumatoid arthritis (RA). However, the effects of such interventions during the early phases of arthritis remain to be clarified. In this study we use the murine delayed-typ...

  8. Preliminary X-ray diffraction analysis of YcdB from Escherichia coli: a novel haem-containing and Tat-secreted periplasmic protein with a potential role in iron transport

    International Nuclear Information System (INIS)

    Cartron, Michaël L.; Mitchell, Sue A.; Woodhall, Mark R.; Andrews, Simon C.; Watson, Kimberly A.

    2006-01-01

    The crystallization and structure determination of the apo form of a novel haem-containing Tat substrate, YcdB from E. coli, has been solved to 2.0 Å resolution. The preliminary structure shows similarity to other haem-dependent peroxidases, despite low sequence homology. YcdB is a periplasmic haem-containing protein from Escherichia coli that has a potential role in iron transport. It is currently the only reported haem-containing Tat-secreted substrate. Here, the overexpression, purification, crystallization and structure determination at 2.0 Å resolution are reported for the apo form of the protein. The apo-YcdB structure resembles those of members of the haem-dependent peroxidase family and thus confirms that YcdB is also a member of this family. Haem-soaking experiments with preformed apo-YcdB crystals have been optimized to successfully generate haem-containing YcdB crystals that diffract to 2.9 Å. Completion of model building and structure refinement are under way

  9. Synthesis, crystal structure, growth, optical and third order nonlinear optical studies of 8HQ2C5N single crystal - An efficient third-order nonlinear optical material

    Energy Technology Data Exchange (ETDEWEB)

    Divya Bharathi, M.; Ahila, G.; Mohana, J. [Department of Physics, Presidency College, Chennai 600005 (India); Chakkaravarthi, G. [Department of Physics, CPCL Polytechnic College, Chennai 600068 (India); Anbalagan, G., E-mail: anbu24663@yahoo.co.in [Department of Nuclear Physics, University of Madras, Chennai 600025 (India)

    2017-05-01

    A neoteric organic third order nonlinear optical material 8-hydroxyquinolinium 2-chloro-5-nitrobenzoate dihydrate (8HQ2C5N) was grown by slow cooling technique using ethanol: water (1:1) mixed solvent. The calculated low value of average etch pit solidity (4.12 × 10{sup 3} cm{sup −2}) indicated that the title crystal contain less defects. From the single crystal X-ray diffraction data, it was endowed that 8HQ2C5N crystal belongs to the monoclinic system with centrosymmetric space group P2{sub 1}/c and the cell parameters values, a = 9.6546 (4) Ǻ, b = 7.1637(3) Ǻ, c = 24.3606 (12) Ǻ, α = γ = 90°, β = 92.458(2)° and volume = 1683.29(13) Ǻ{sup 3}. The FT-IR and FT-Raman spectrum were used to affirm the functional group of the title compound. The chemical structure of 8HQ2C5N was scrutinized by {sup 13}C and {sup 1}H NMR spectral analysis and thermal stability through the differential scanning calorimetry study. Using optical studies the lower cut-off wavelength and optical band gap of 8HQ2C5N were found to be 364 nm and 3.17 eV respectively. Using the single oscillator model suggested by Wemple – Didomenico, the oscillator energy (E{sub o}), the dispersion energy (E{sub d}) and static dielectric constant (ε{sub o}) were estimated. The third-order susceptibility were determined as Im χ{sup (3)} = 2.51 × 10{sup −5} esu and Re χ{sup (3)} = 4.46 × 10{sup −7} esu. The theoretical third-order nonlinear optical susceptibility χ{sup (3)} was calculated and the results were compared with experimental value. Photoluminescence spectrum of 8HQ2C5N crystal showed the yellow emission. The crystal had the single shot laser damage threshold of 5.562 GW/cm{sup 2}. Microhardness measurement showed that 8HQ2C5N belongs to a soft material category. - Highlights: • A new organic single crystals were grown and the crystal structure was reported. • Crystal possess, good transmittance, thermal and mechanical stability. • Single shot LDT value is found to be

  10. Differential effects of miR-34c-3p and miR-34c-5p on SiHa cells proliferation apoptosis, migration and invasion

    Energy Technology Data Exchange (ETDEWEB)

    Lopez, Jesus Adrian [Laboratorio de Terapia Genica, Departamento de Genetica y Biologia Molecular, CINVESTAV, Av. IPN 2508, Mexico 07360 D.F. (Mexico); Alvarez-Salas, Luis Marat, E-mail: lalvarez@cinvestav.mx [Laboratorio de Terapia Genica, Departamento de Genetica y Biologia Molecular, CINVESTAV, Av. IPN 2508, Mexico 07360 D.F. (Mexico)

    2011-06-10

    Highlights: {yields} In this study we examine miR-34c-3p and miR-34c-5p functions in SiHa cells. {yields} We study miRNA effect on cell proliferation, anchorage independent growth, apoptosis, cell motility and invasion. {yields} We find that miR-34c-3p and miR-34c-5p inhibition of proliferation and anchorage independent growth are exclusive to SiHa cells. {yields} miR-34c-3p induces apoptosis and inhibits cell motility and invasion in SiHa cells. {yields} In this study we conclude that miR-34c-3p functions as a tumor suppressor differ from miR-34c-5p. -- Abstract: MicroRNAs (miRNA) regulate expression of several genes associated with human cancer. Here, we analyzed the function of miR-34c, an effector of p53, in cervical carcinoma cells. Expression of either miR-34c-3p or miR-34c-5p mimics caused inhibition of cell proliferation in the HPV-containing SiHa cells but not in other cervical cells irrespective of tumorigenicity and HPV content. These results suggest that SiHa cells may lack of regulatory mechanisms for miR-34c. Monolayer proliferation results showed that miR-34c-3p produced a more pronounced inhibitory effect although both miRNAs caused inhibition of anchorage independent growth at similar extent. However, ectopic expression of pre-miR-34c-3p, but not pre-miR-34c-5p, caused S-phase arrest in SiHa cells triggering a strong dose-dependent apoptosis. A significant inhibition was observed only for miR-34c-3p on SiHa cells migration and invasion, therefore implying alternative regulatory pathways and targets. These results suggest differential tumor suppressor roles for miR-34c-3p and miR-34c-5p and provide new insights in the understanding of miRNA biology.

  11. Differential effects of miR-34c-3p and miR-34c-5p on SiHa cells proliferation apoptosis, migration and invasion

    International Nuclear Information System (INIS)

    Lopez, Jesus Adrian; Alvarez-Salas, Luis Marat

    2011-01-01

    Highlights: → In this study we examine miR-34c-3p and miR-34c-5p functions in SiHa cells. → We study miRNA effect on cell proliferation, anchorage independent growth, apoptosis, cell motility and invasion. → We find that miR-34c-3p and miR-34c-5p inhibition of proliferation and anchorage independent growth are exclusive to SiHa cells. → miR-34c-3p induces apoptosis and inhibits cell motility and invasion in SiHa cells. → In this study we conclude that miR-34c-3p functions as a tumor suppressor differ from miR-34c-5p. -- Abstract: MicroRNAs (miRNA) regulate expression of several genes associated with human cancer. Here, we analyzed the function of miR-34c, an effector of p53, in cervical carcinoma cells. Expression of either miR-34c-3p or miR-34c-5p mimics caused inhibition of cell proliferation in the HPV-containing SiHa cells but not in other cervical cells irrespective of tumorigenicity and HPV content. These results suggest that SiHa cells may lack of regulatory mechanisms for miR-34c. Monolayer proliferation results showed that miR-34c-3p produced a more pronounced inhibitory effect although both miRNAs caused inhibition of anchorage independent growth at similar extent. However, ectopic expression of pre-miR-34c-3p, but not pre-miR-34c-5p, caused S-phase arrest in SiHa cells triggering a strong dose-dependent apoptosis. A significant inhibition was observed only for miR-34c-3p on SiHa cells migration and invasion, therefore implying alternative regulatory pathways and targets. These results suggest differential tumor suppressor roles for miR-34c-3p and miR-34c-5p and provide new insights in the understanding of miRNA biology.

  12. Biomass pre-treatment for co-production of high-concentration C5- and C6-carbohydrates and their derivatives

    Science.gov (United States)

    Dumesic, James A.; Martin Alonso, David; Luterbacher, Jeremy Scott

    2016-06-07

    Described is a method of processing biomass to separate it into a liquid fraction enriched in solubilized C5-sugar-containing oligomers and C-5 sugar monomers and a solid fraction enriched in substantially insoluble cellulose and C6-sugar-containing oligomers. The method includes the steps of reacting biomass with a solvent system comprising water, at least one lactone, or at least one furan, or at least one cyclic ether, and at least one acid, for a time and at a temperature to yield the liquid and solid fractions. The liquid and solid fractions may then be separated. Gamma-valeroloactone is a preferred lactone for use in the solvent system. Tetrahydrofuran is a preferred furan species for use in the solvent system.

  13. Structural analysis of CYP2C9 and CYP2C5 and an evaluation of commonly used molecular modeling techniques

    DEFF Research Database (Denmark)

    Afzelius, Lovisa; Raubacher, Florian; Karlén, Anders

    2004-01-01

    , newly built homology models, and repeated molecular dynamics simulations. The CPCA was based on molecular interaction fields focused on the active site regions of the proteins and include detailed amino acid analysis. The comparison of the CYP2C9 and CYP2C5 crystal structures revealed differences...... improved the similarity to the crystal target in some cases and could be recommended even though it requires a careful manual alignment process. The application of molecular dynamics simulations to highly flexible proteins such as cytochromes P450 is also explored and the information is extracted...... in the flexible regions such as the B-C and F-G loop and the N and C termini. Cross homology models of CYP2C9 and CYP2C5, using their respective crystal structures as templates, indicated that such models were more similar to their templates than to their target proteins. Inclusion of multiple templates slightly...

  14. IFN-γ-producing NKT cells exacerbate sepsis by enhancing C5a generation via IL-10-mediated inhibition of CD55 expression on neutrophils.

    Science.gov (United States)

    Kim, Ji Hyung; Oh, Sae Jin; Ahn, Sehee; Chung, Doo Hyun

    2014-07-01

    A role for NKT cells has been implicated in sepsis, but the mechanism by which NKT cells contribute to sepsis remains unclear. Here, we examined WT and NKT-cell-deficient mice of C57BL/6 background during cecal ligation and puncture-induced sepsis. The levels of C5a, IFN-γ, and IL-10 were higher in the serum and peritoneal fluid of WT mice than in those of CD1d(-/-) mice, while the mortality rate was lower in CD1d(-/-) mice than in WT mice. C5a blockade decreased mortality of WT mice during sepsis, whereas it did not alter that of CD1d(-/-) mice. As assessed by intracellular staining, NKT cells expressed IFN-γ, while neutrophils expressed IL-10. Upon coculture, IL-10-deficient NKT cells enhanced IL-10 production by WT, but not IFN-γR-deficient, neutrophils. Meanwhile, CD1d(-/-) mice exhibited high CD55 expression on neutrophils during sepsis, whereas those cells from WT mice expressed minimal levels of CD55. Recombinant IL-10 administration into CD1d(-/-) mice reduced CD55 expression on neutrophils. Furthermore, adoptive transfer of sorted WT, but not IFN-γ-deficient, NKT cells into CD1d(-/-) mice suppressed CD55 expression on neutrophils, but increased IL-10 and C5a levels. Taken together, IFN-γ-producing NKT cells enhance C5a generation via IL-10-mediated inhibition of CD55 expression on neutrophils, thereby exacerbating sepsis. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Evidence for an anisotropic contact shift. Proton NMR study of line shapes in uranocene and (C5H5)3UCl powders

    International Nuclear Information System (INIS)

    McGarvey, B.R.; Nagy, S.

    1987-01-01

    The proton NMR spectra of solid powders of uranocene and (C 5 H 5 ) 3 UCl were measured from 90 to 298 K. The line shapes of both systems became increasingly anisotropic as the temperature was lowered. The cyclooctatetraene rings in uranocene were found to be rotating at a frequency greater than 100 kHz down to 90 K. The (C 5 H 5 ) 3 UCl molecules were found to be reorienting rapidly above 220 K, but below 140 K the NMR spectra were characteristic of a rigid lattice with no rotation of the cyclopentadienyl rings. The spectra of both compounds could be simulated by assuming an axial paramagnetic shift tensor and an orientation-dependent line width. Comparison of the experimental shift tensor with that calculated for a point dipolar interaction revealed a large and very anisotropic paramagnetic shift for uranocene due to unpaired spin transferred into the ligand orbitals. The shift was large when the magnetic field was along the 8-fold symmetry axis of the molecule and nearly zero perpendicular to the axis. It appears conclusive that the contact shift in uranocene is not isotropic at all. A similar anisotropy in the contact shift associated with the cyclopentadienyl rings is evident also in the results for (C 5 H 5 )UCl. The average solid-state shift of uranocene agreed with the solution shift, within experimental error, but the solid state shift of (C 5 H 5 ) 3 UCl was 42 ppm greater than the solution shift at 298 K, indicating a difference in molecular geometry between the crystalline state and solution. 32 references, 8 figures, 3 tables

  16. Validation of PROBA-V GEOV1 and MODIS C5 & C6 fAPAR Products in a Deciduous Beech Forest Site in Italy

    Czech Academy of Sciences Publication Activity Database

    Nestola, E.; Sanchez-Zapero, J.; Latorre, C.; Mazzenga, F.; Matteucci, G.; Calfapietra, Carlo; Camacho, F.

    2017-01-01

    Roč. 9, č. 2 (2017), č. článku 126. ISSN 2072-4292 Institutional support: RVO:86652079 Keywords : fAPAR * validation * PROBA-V GEOV1 * MODIS C5 * MODIS C6 * beech forest * up-scaling * GCOS requirements * in-situ comparison and evaluation Subject RIV: EH - Ecology, Behaviour OBOR OECD: Environmental sciences (social aspects to be 5.7) Impact factor: 3.244, year: 2016

  17. New technique targeting the C5 nerve root proximal to the traditional interscalene sonoanatomical approach is analgesic for outpatient arthroscopic shoulder surgery.

    Science.gov (United States)

    Dobie, Katherine H; Shi, Yaping; Shotwell, Matthew S; Sandberg, Warren S

    2016-11-01

    Regional anesthesia and analgesia for shoulder surgery is most commonly performed via interscalene nerve block. We developed an ultrasound-guided technique that specifically targets the C5 nerve root proximal to the traditional interscalene block and assessed its efficacy for shoulder analgesia. Prospective case series. Vanderbilt Bone and Joint Surgery Center. Patients undergoing shoulder arthroscopy at an ambulatory surgery center. Thirty-five outpatient shoulder arthroscopy patients underwent an analgesic nerve block using a new technique where ultrasound visualization of the C5 nerve root served as the primary target at a level proximal to the traditional interscalene approach. The block was performed with 15mL of 0.5% plain ropivicaine. Post anesthesia care unit pain scores, opioid consumption, hand strength, and duration of block were recorded. Cadaver dissection after injection with methylene blue confirmed that the primary target under ultrasound visualization was the C5 nerve root. Pain scores revealed 97% patients had 0/10 pain at arrival to PACU, with 91% having a pain score of 3/10 or less at discharge from PACU. Medical Research Council (MRC) hand strength mean (SD) score was 4.17 (0.92) on a scale of 1-5. The mean (SD) duration of the block was 13.9 (3.5) hours. A new technique for ultrasound-guided blockade at the level of the C5 nerve root proximal to the level of the traditional interscalene block is efficacious for shoulder post-operative pain control. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Effects of C5/C6 Intervertebral Space Distraction Height on Pressure on the Adjacent Intervertebral Disks and Articular Processes and Cervical Vertebrae Range of Motion.

    Science.gov (United States)

    Lu, Tingsheng; Luo, Chunshan; Ouyang, Beiping; Chen, Qiling; Deng, Zhongliang

    2018-04-25

    BACKGROUND This study aimed to investigate the association between range of motion of the cervical vertebrae and various C5/C6 intervertebral space distraction heights. MATERIAL AND METHODS The cervical vertebrae from 6 fresh adult human cadavers were used to prepare the models. Changes in C4/C5 and C6/C7 intervertebral disk pressures, articular process pressure, and range of motion of the cervical vertebrae before and after the distraction of the C5/C6 intervertebral space at benchmark heights of 100%, 120%, 140%, and 160% were tested under different exercise loads. RESULTS The pressure on the adjacent intervertebral disks was highest with the standing upright position before distraction, varied with different positions of the specimens and distraction heights after distraction, and was closest to that before distraction at a distraction height of 120% (Particular processes was highest with left and right rotations before distraction, varied with different positions of the specimens and distraction heights after distraction, and was lowest under the same exercise load with different positions at a distraction height of 120% (Pdistraction and at a distraction height of 120% after distraction, respectively (Particular processes and range of motion of the cervical vertebrae and is therefore an appropriate intervertebral space distraction height.

  19. Optimizing C4+ and C5+ beams of the Kei2 electron cyclotron resonance ion source using a special gas-mixing technique

    International Nuclear Information System (INIS)

    Drentje, A.G.; Muramatsu, M.; Kitagawa, A.

    2006-01-01

    With the prototype electron cyclotron resonance ion source for the next carbon therapy facility in Japan a series of measurements has been performed in order (a) to find the best condition for producing high beam currents of C 4+ ions, and (b) to study the effect of 'special' gas mixing by using a chemical compound as a feed gas. The effect would then appear as an increase in high charge state production in this case of C 5+ ions. In 'regular' gas-mixing experiments it is well known that an isotopic phenomenon occurs: a heavier isotope of the mixing gas is increasing the production of high charge states of the beam gas ions. A similar isotopic effect has been found in the present experiment: with deuterated methane (CD 4 gas) the C 5+ beam currents are about 10% higher than with regular methane (CH 4 gas). The 'mixing-gas' ratio D (or H) to C can be decreased by choosing, e.g., butane gas; in this case the isotopic effect for C 5+ production is even stronger (>15%). For production of C 4+ ions the isotopic effect appears to be absent. Clearly this is related to the much easier production. It turns out that the relative amount of carbon is much more important: butane gives about 10% higher C 4+ -ion currents than methane

  20. Predictable topography simulation of SiO2 etching by C5F8 gas combined with a plasma simulation, sheath model and chemical reaction model

    International Nuclear Information System (INIS)

    Takagi, S; Onoue, S; Iyanagi, K; Nishitani, K; Shinmura, T; Kanoh, M; Itoh, H; Shioyama, Y; Akiyama, T; Kishigami, D

    2003-01-01

    We have developed a simulation for predicting reactive ion etching (RIE) topography, which is a combination of plasma simulation, the gas reaction model, the sheath model and the surface reaction model. The simulation is applied to the SiO 2 etching process of a high-aspect-ratio contact hole using C 5 F 8 gas. A capacitively coupled plasma (CCP) reactor of an 8-in. wafer was used in the etching experiments. The baseline conditions are RF power of 1500 W and gas pressure of 4.0 Pa in a gas mixture of Ar, O 2 and C 5 F 8 . The plasma simulation reproduces the tendency that CF 2 radical density increases rapidly and the electron density decreases gradually with increasing gas flow rate of C 5 F 8 . In the RIE topography simulation, the etching profiles such as bowing and taper shape at the bottom are reproduced in deep holes with aspect ratios greater than 19. Moreover, the etching profile, the dependence of the etch depth on the etching time, and the bottom diameter can be predicted by this simulation

  1. An organic solvent-, detergent-, and thermo-stable alkaline protease from the mesophilic, organic solvent-tolerant Bacillus licheniformis 3C5.

    Science.gov (United States)

    Rachadech, W; Navacharoen, A; Ruangsit, W; Pongtharangkul, T; Vangnai, A S

    2010-01-01

    Bacillus licheniformis 3C5, isolated as mesophilic bacterium, exhibited tolerance towards a wide range of non-polar and polar organic solvents at 45 degrees C. It produced an extracellular organic solvent-stable protease with an apparent molecular mass of approximately 32 kDa. The inhibitory effect of PMSF and EDTA suggested it is likely to be an alkaline serine protease. The protease was active over abroad range of temperatures (45-70 degrees C) and pH (8-10) range with an optimum activity at pH 10 and 65 degrees C. It was comparatively stable in the presence ofa relatively high concentration (35% (v/v)) of organic solvents and various types of detergents even at a relatively high temperature (45 degrees C). The protease production by B. licheniformis 3C5 was growth-dependent. The optimization of carbon and nitrogen sources for cell growth and protease production revealed that yeast extract was an important medium component to support both cell growth and the protease production. The overall properties of the protease produced by B. licheniformis 3C5 suggested that this thermo-stable, solvent-stable, detergent-stable alkaline protease is a promising potential biocatalyst for industrial and environmental applications.

  2. Synthesis and structural characterization of PHP[(C(5)Me(4))(2)], a monodentate chiral phosphine derived from intramolecular C-C coupling of tetramethylcyclopentadienyl groups: an evaluation of steric and electronic properties.

    Science.gov (United States)

    Shin, J H; Bridgewater, B M; Churchill, D G; Parkin, G

    2001-10-22

    The chiral monodentate phosphine PhP[(C(5)Me(4))(2)] is readily obtained by oxidation of the lithium complex Li(2)[PhP(C(5)Me(4))(2)] with I(2), which couples the two cyclopentadienyl groups to form a five-membered heterocyclic ring. The steric and electronic properties of PhP[(C(5)Me(4))(2)] have been evaluated by X-ray diffraction and IR spectroscopic studies on a variety of derivatives, including Ph[(C(5)Me(4))(2)]PE (E = S, Se), Cp*MCl(4)[P[(C(5)Me(4))(2)]Ph] (M = Mo, Ta), Ir[P[(C(5)Me(4))(2)]Ph](2)(CO)Cl, and CpFe(CO)[PhP[(C(5)Me(4))(2)

  3. Atmospheric histories and growth trends of C4F10, C5F12, C6F14, C7F16 and C8F18

    Directory of Open Access Journals (Sweden)

    R. F. Weiss

    2012-05-01

    Full Text Available Atmospheric observations and trends are presented for the high molecular weight perfluorocarbons (PFCs: decafluorobutane (C4F10, dodecafluoropentane (C5F12, tetradecafluorohexane (C6F14, hexadecafluoroheptane (C7F16 and octadecafluorooctane (C8F18. Their atmospheric histories are based on measurements of 36 Northern Hemisphere and 46 Southern Hemisphere archived air samples collected between 1973 to 2011 using the Advanced Global Atmospheric Gases Experiment (AGAGE "Medusa" preconcentration gas chromatography-mass spectrometry systems. A new calibration scale was prepared for each PFC, with estimated accuracies of 6.8% for C4F10, 7.8% for C5F12, 4.0% for C6F14, 6.6% for C7F16 and 7.9% for C8F18. Based on our observations the 2011 globally averaged dry air mole fractions of these heavy PFCs are: 0.17 parts-per-trillion (ppt, i.e., parts per 1012 for C4F10, 0.12 ppt for C5F12, 0.27 ppt for C6F14, 0.12 ppt for C7F16 and 0.09 ppt for C8F18. These atmospheric mole fractions combine to contribute to a global average radiative forcing of 0.35 mW m−2, which is 6% of the total anthropogenic PFC radiative forcing (Montzka and Reimann, 2011; Oram et al., 2012. The growth rates of the heavy perfluorocarbons were largest in the late 1990s peaking at 6.2 parts per quadrillion (ppq, i.e., parts per 1015 per year (yr for C4F10, at 5.0 ppq yr−1 for C5F12 and 16.6 ppq yr−1 for C6F14 and in the early 1990s for C7F16 at 4.7 ppq yr−1 and in the mid 1990s for C8F18 at 4.8 ppq yr−1. The 2011 globally averaged mean atmospheric growth rates of these PFCs are subsequently lower at 2.2 ppq yr−1 for C4F10, 1.4 ppq yr−1 for C5F12, 5.0 ppq yr−1 for C6F14, 3.4 ppq yr−1 for C7F16 and 0.9 ppq yr−1 for C8F18. The more recent slowdown in the growth rates suggests that emissions are declining as compared to the 1980s and 1990s.

  4. Synthesis and Electronic Structure of Dissymmetrical, Naphthalene-Bridged Sandwich Complexes [Cp ' Fe(mu-C10H8)MCp*](x) (x=0,+1; M = Fe, Ru; Cp ' = eta(5)-C5H2-1,2,4-tBu(3); Cp* = eta(5)-C5Me5)

    NARCIS (Netherlands)

    Malberg, J.; Lupton, E.; Schnöckelborg, E.M.; de Bruin, B.; de Sutter, J.; Meyer, K.; Hartl, F.; Wolf, R.

    2013-01-01

    The dissymmetrical naphthalene-bridged complexes [Cp'Fe(mu-C10H8)FeCp*] (3; Cp* = eta(5)-C5Me5, Cp' = eta(5)-C5H2-1,2,4-tBu(3)) and [Cp'Fe(mu-C10H8)RuCp*] (4) were synthesized via a one-pot procedure from FeCl2(thf)(1.5), Cp'K, KC10H8, and [Cp*FeCl(tmeda)] (tmeda =

  5. Reaction of ether and thioether functionalised 1-alkenes with the cationic permethylzirconocene olefin polymerisation catalyst [(eta(5)-C5Me5)(2)ZrMe](+). Molecular structure of the insertion product [(eta(5)-C5Me5)(2)ZrCH2CH(Me)CH2OEt](+)

    NARCIS (Netherlands)

    Bijpost, Erik A; Zuideveld, Martin A.; Meetsma, Auke; Teuben, Jan H

    1998-01-01

    Reaction of [(η5-C5Me5)2ZrMe][MeB(C6F5)3] (1) with (thio)ether functionalised alkenes: 3-ethoxy-1-propene and 3-(methylthio)-1-propene gives stable insertion products [(η5-C5Me5)2ZrCH2CH(Me)CH2XR][MeB(C6F5)3] (2: X = O, R = Et; 3: X = S, R = Me) in which the (thio)ether function is intramolecularly

  6. A Novel simultaneous-Saccharification-Fermentation Strategy for Efficient Co-fermentation of C5 and C6 Sugars Using Native, Non-GMO Yeasts

    Energy Technology Data Exchange (ETDEWEB)

    Varanasi, Sasidhar [Univ. of Toledo, OH (United States); Relue, Patricia [Univ. of Toledo, OH (United States)

    2013-09-30

    Economic bioethanol production is critically dependent upon the ability to convert both the hexose (C6) and pentose (C5) sugars resulting from cellulose and hemicellulose. C5 sugars are not readily fermentable by native Saccharomyces cerevisiae. Genetically Modified Organisms (GMOs) are designed to ferment xylose, but their stability, ethanol yield, environmental impact, and survival under conditions of industrial fermentation are unproven. In this project, we developed a novel approach for efficient fermentation of both C5 and C6 sugars using native S. Cerevisiae by exploiting its ability to produce ethanol from xylulose - the keto-isomer of xylose. While the isomerization of xylose to xylulose can be accomplished via commercially (and cheaply) available Xylose Isomerase (XI) (Sweetzyme™), this conversion has an extremely unfavorable equilibrium (xylose:xylose is about 5:1). To address this, we developed two alternate strategies. In the first, the two enzymes XI and urease are coimmobilized on solid support particles to enable complete isomerization of xylose to xylulose under pH conditions suitable for fermentation, in a simultaneous-isomerization-fermentation (SIF) mode. The ability of our technology to conduct isomerization of xylose under pH conditions suitable for both saccharification and fermentation opens the possibility of SSF with native yeasts for the first time. Herein, we performed specific research tasks for implementation of our technology in several modes of operation, including simultaneous-isomerization-and-fermentation (SIF), simultaneous-saccharification-and-isomerization (SSI) followed by fermentation, and SSF mode with the biomass feedstock poplar. The projected economics of our process are very favorable in comparison to the costs associated with engineering, licensing and propagating GMOs. This novel fermentation technology is readily accessible to rural farming economies for implementation in cellulosic ethanol production facilities.

  7. Quadriplegia recovery after hemi-section and transplant model of spinal cord at the level of C5 and C6.

    Science.gov (United States)

    Bitar-Alatorre, W E; Segura-Torres, J E; Rosales-Corral, S A; Jiménez-Avila, J M; Huerta-Viera, M

    2011-03-10

    A spinal cord hemi-section with a homologous transplant of medullar tissue at the level of C5-C6 and preservation of the anterior spinal artery was used to evaluate the histological characteristics such as quantity and quality of axons, myelin index and blood vessels after quadriplegia recovery. Vascular changes after spinal injury results in severe endothelial damage, axonal edema, neuronal necrosis and demyelinization as well as cysts and infarction. Preservation of the anterior spinal artery has demonstrated clinical recuperation; therefore, in addition to the lesion we included a homologous transplant to visualize changes at a cellular level. Two groups of dogs (hemi-section and transplant) went through a traumatic spinal cord hemi-section of 50% at the level of C5-C6. The transplant group formed by animals which simultaneously had 4 mm of spinal cord removed and the equal amount substituted from a donor animal at the level of C5-C6 corresponding to the half right side; both preserving the anterior spinal artery. Histological evaluation of all groups took place at days 3 (acute) and 28 (chronic) post-operation. Changes of degeneration and axonal regeneration were found in the hemi-section and transplant groups at acute and chronic time, as well as same quadriplegia recovery at chronic time in the hemi-section and transplant groups which closely related to mechanisms which participate in regeneration and functional recuperation due to the preservation of the anterior spinal artery and presence of new blood vessels. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  8. Synthesis, Characterization and In Vitro Anticancer Activity of C-5 Curcumin Analogues with Potential to Inhibit TNF-α-Induced NF-κB Activation

    Directory of Open Access Journals (Sweden)

    Amit Anthwal

    2014-01-01

    Full Text Available In a search of new compounds active against cancer, synthesis of a series of C-5 curcumin analogues was carried out. The new compounds demonstrated good cytotoxicity against chronic myeloid leukemia (KBM5 and colon cancer (HCT116 cell lines. Further, these compounds were found to have better potential to inhibit TNF-α-induced NF-κB activation in comparison to curcumin, which show their potential to act as anti-inflammatory agents. Some compounds were found to show higher cytotoxicity against cancer cell lines in comparison to curcumin used as standard.

  9. CFH Y402H polymorphism and the complement activation product C5a: effects on NF-κB activation and inflammasome gene regulation.

    Science.gov (United States)

    Cao, Sijia; Wang, Jay Ching Chieh; Gao, Jiangyuan; Wong, Matthew; To, Elliott; White, Valerie A; Cui, Jing Z; Matsubara, Joanne A

    2016-05-01

    The Y402H polymorphism in the complement factor H (CFH) gene is an important risk factor for age-related macular degeneration (AMD). Complement activation products and proinflammatory cytokines are associated with this polymorphism at the systemic level, but less is known of the associations in the outer retina of the genotyped eye. Here we investigate complement activation products and their role in nuclear factor (NF)-κB activation and gene expression of the NLRP3 inflammasome pathway. Postmortem donor eyes were genotyped for the CFH Y402H polymorphism and assessed for complement C3a, C5a, interleukin (IL)-18 and tumour necrosis factor (TNF)-α. ARPE19 cells were stimulated basolaterally with C5a or TNF-α in polarised cultures. NF-κB activation was assessed with a reporter cell line. Gene expression of inflammasome-related (NLRP3, caspase-1, IL-1β and IL-18) and classic inflammatory (IL-6 and IL-8) genes was studied. The distribution of inflammasome products, IL-1β and IL-18, was studied in postmortem donor eyes with AMD pathologies. Eyes with the homozygous at-risk variant demonstrated higher levels of C5a, IL-18 and TNF-α in Bruch's membrane and choroid. C5a promoted NF-κB activation and upregulation of IL-18 in polarised ARPE19. TNF-α promoted NF-κB activation and gene expression of caspase-1, IL-1β, IL-18, IL-6 and IL-8, but downregulated NLRP3. In eyes with geographic atrophy, strong immunoreactivity was observed for inflammasome products IL-1β and IL-18 compared with age-matched controls. The at-risk polymorphism of the CFH Y402H may contribute to AMD disease process through increased complement and NF-κB activation, and the upregulation of IL-18, a product of inflammasome activation. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  10. Immunoscintigraphy of adenocarcinomas by means of 111In-labelled F(ab')2 fragments of anti-CEA monoclonal antibody F023C5

    International Nuclear Information System (INIS)

    Riva, P.; Paganelli, G.; Callegaro, L.

    1988-01-01

    F(ab') 2 fragments of F023C5, an anti-CEA monoclonal antibody, were conjugated to diethylenetriamine pentaacetic acid (DTPA) and converted into a ready to use reagent for instant 111 In-labelling. The resulting 111 In radiopharmaceutical was administered intravenously and tested for its ability to image (at 48-72 h after administration) 31 primary and 85 metastatic carcinoma lesions in 70 adenocarcinoma patients (26 gastrointestinal, 18 breast and 26 lung tumour patients) whose serum CEA was elevated in 43 cases and normal in the other 27. (author)

  11. Utilisation of an eta(3)-allyl hydride complex, formed by UV irradiation, as a controlled source of 16-electron (eta(5)-C(5)Me(5))Rh(CH(2)[double bond, length as m-dash]CHMe).

    Science.gov (United States)

    Sexton, Catherine J; López-Serrano, Joaquín; Lledós, Agustí; Duckett, Simon B

    2008-10-21

    Low temperature UV irradiation of solutions of (eta(5)-C(5)Me(5))Rh(CH(2)[double bond, length as m-dash]CHMe)(2) yields (eta(5)-C(5)Me(5))Rh(eta(3)-CH(2)CHCH(2))(H), which provides controlled access to the 16-electron fragment (eta(5)-C(5)Me(5))Rh(CH(2)[double bond, length as m-dash]CHMe).

  12. Cocaine-associated retiform purpura: a C5b-9-mediated microangiopathy syndrome associated with enhanced apoptosis and high levels of intercellular adhesion molecule-1 expression.

    Science.gov (United States)

    Magro, Cynthia M; Wang, Xuan

    2013-10-01

    Cocaine-associated retiform purpura is a recently described entity characterized by striking hemorrhagic necrosis involving areas of skin associated with administration of cocaine. Levamisole, an adulterant in cocaine, has been suggested as the main culprit pathogenetically. Four cases of cocaine-associated retiform purpura were encountered in the dermatopathology practice of C. M. Magro. The light microscopic findings were correlated with immunohistochemical and immunofluorescence studies. All 4 cases showed a very striking thrombotic diathesis associated with intravascular macrophage accumulation. Necrotizing vasculitis was noted in 1 case. Striking intercellular adhesion molecule-1 (ICAM-1)/CD54 expression in vessel wall along with endothelial expression of caspase 3 and extensive vascular C5b-9 deposition was observed in all biopsies examined. Cocaine-induced retiform purpura is a C5b-9-mediated microvascular injury associated with enhanced apoptosis and prominent vascular expression of ICAM-1, all of which have been shown in prior in vitro and in vivo murine models to be a direct effect of cocaine metabolic products. Antineutrophilic cytoplasmic antibody and antiphospholipid antibodies are likely the direct sequelae of the proapoptotic microenvironment. The inflammatory vasculitic lesion could reflect the downstream end point reflective of enhanced ICAM-1 expression and the development of antineutrophilic cytoplasmic antibody. Levamisole likely works synergistically with cocaine in the propagation of this syndromic complex.

  13. Studies on the O-specific polysaccharide of the lipopolysaccharide from the Pseudomonas mediterranea strain C5P1rad1, a bacterium pathogenic of tomato and chrysanthemum.

    Science.gov (United States)

    Zdorovenko, Evelina L; Cimmino, Alessio; Marchi, Guido; Shashkov, Alexander S; Fiori, Mario; Knirel, Yuriy A; Evidente, Antonio

    2017-08-07

    An O-specific polysaccharide (OPS) was isolated from the lipopolysaccharide of Pseudomonas mediterranea strain C5P1rad1, the causal agents of tomato pith necrosis and Chrysanthemum stem rot, and studied by one- and two-dimensional 1 H and 13 C NMR spectroscopy. The following structure of the trisaccharide repeating unit of the OPS was established, which, to our knowledge, is unique among the known bacterial polysaccharide structures: →4)-β-d-ManpNAc3NAcA-(1 → 4)-β-d-ManpNAc3NAcA-(1 → 3)-α-d-QuipNAc4NAc-(1→ where QuiNAc4NAc and ManNAc3NAcA indicate 2,4-diacetamido-2,4,6-trideoxyglucose and 2,3-diacetamido-2,3-dideoxymannuronic acid, respectively. Pre-treatment of leaves with LPS or OPS preparations at 250 and 50 μg mL -1 did not inhibit development of a hypersensitivity reaction induced by P. mediterranea C5P1rad1 on tobacco, tomato and chrysanthemum plants. The same preparations at 250 μg mL -1 partially prevented elicitation of the hypersensitivity reaction by Pseudomonas syringae KVPT7RC on chrysanthemum but not tobacco and tomato. Copyright © 2017. Published by Elsevier Ltd.

  14. Application of backflush and micro-flow techniques to the analysis of C5-C13 hydrocarbons in crude oils and its geochemical significance

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    An Agilent 6890N GC equipped with both FID and Agilent 5975 MSD analyzer has been employed to analyze C5-C13 hydrocarbon fractions of crude oils. A technical combination of program temperature volatilizer injection, backflush and micro-flow controller afforded a fine separation of C5-C13 compounds on a PONA column with the heavy part of crude oils being cut off before entering the analytical column. Both GC-FID chromatogram and GC-MS mass chromatograrns (MID and full scan) could be obtained at the same time. The retension time differences of nC6-nC13 alkanes between GC and TIC were in the range of 0.02-0. 58 minutes. Totally 286 peaks have been assigned group compositions. Results on 8 typical oil samples from CNPC Key Laboratory Crude Oil Library showed that the characteristics of C6-C13 hydrocarbon group composition could be used in oil-oil correlation studies.

  15. Structural, bonding, anisotropic mechanical and thermal properties of Al4SiC4 and Al4Si2C5 by first-principles investigations

    Directory of Open Access Journals (Sweden)

    Liang Sun

    2016-09-01

    Full Text Available The structural, bonding, electronic, mechanical and thermal properties of ternary aluminum silicon carbides Al4SiC4 and Al4Si2C5 are investigated by first-principles calculations combined with the Debye quasi-harmonic approximation. All the calculated mechanical constants like bulk, shear and Young's modulus are in good agreement with experimental values. Both compounds show distinct anisotropic elastic properties along different crystalline directions, and the intrinsic brittleness of both compounds is also confirmed. The elastic anisotropy of both aluminum silicon carbides originates from their bonding structures. The calculated band gap is obtained as 1.12 and 1.04 eV for Al4SiC4 and Al4Si2C5 respectively. From the total electron density distribution map, the obvious covalent bonds exist between Al and C atoms. A distinct electron density deficiency sits between AlC bond along c axis among Al4SiC4, which leads to its limited tensile strength. Meanwhile, the anisotropy of acoustic velocities for both compounds is also calculated and discussed.

  16. Excretion of complement proteins and its activation marker C5b-9 in IgA nephropathy in relation to renal function

    Directory of Open Access Journals (Sweden)

    Onda Kisara

    2011-11-01

    Full Text Available Abstract Background Glomerular damage in IgA nephropathy (IgAN is mediated by complement activation via the alternative and lectin pathways. Therefore, we focused on molecules stabilizing and regulating the alternative pathway C3 convertase in urine which might be associated with IgAN pathogenesis. Methods Membrane attack complex (MAC, properdin (P, factor H (fH and Complement receptor type 1 (CR1 were quantified in urine samples from 71 patients with IgAN and 72 healthy controls. Glomerular deposition of C5, fH and P was assessed using an immunofluorescence technique and correlated with histological severity of IgAN and clinical parameters. Fibrotic changes and glomerular sclerosis were evaluated in renal biopsy specimens. Results Immunofluorescence studies revealed glomerular depositions of C5, fH and P in patients with IgAN. Urinary MAC, fH and P levels in IgAN patients were significantly higher than those in healthy controls (p Conclusions Complement activation occurs in the urinary space in IgAN and the measurement of levels of MAC and fH in the urine could be a useful indicator of renal injury in patients with IgAN.

  17. Influência da mono-hidrogenação da fração C5 na síntese do TAME usando Amberlyst 15 como catalisador Influence of mono-hydrogenation of C5 cut on the synthesis of TAME using Amberlyst 15

    Directory of Open Access Journals (Sweden)

    Gilberto da Cunha Gonçalves

    2001-05-01

    Full Text Available No presente trabalho, foi estudada a síntese do TAME, em fase líquida, a partir de uma fração C5 e metanol, utilizando Amberlyst 15 como catalisador. A fração C5 utilizada possui uma diolefina, que tem uma alta tendência à formação de gomas e um alto teor de mono-olefinas. Deste modo, o objetivo deste trabalho foi avaliar o efeito da mono-hidrogenação da fração C5 na síntese do TAME. A hidrogenação foi feita a 80oC e 10 kgf/cm2 de H2, usando um catalisador 0,3% Pt/Al2O3. A diolefina foi totalmente hidrogenada e o teor de mono-olefinas significativamente reduzido sem um decréscimo apreciável no teor de isoamilenos reativos. A eterificação foi feita em um reator tipo batelada de 250 mL, com agitação magnética. A temperatura foi variada na faixa de 50 a 90oC, com uma pressão de 10 kgf/cm2 e razão molar isoamileno/metanol de aproximadamente um. Os produtos de reação foram analisados por cromatografia gasosa. A conversão total observada foi aproximadamente a mesma para o os cortes original e mono-hidrogenado. Entretanto, os produtos obtidos utilizando a fração C5 original apresentaram cheiro forte e coloração, mesmos para os testes a temperaturas mais baixas, que são características da formação de gomas. Por outro lado, quando a fração mono-hidrogenada foi usada na eterificação, o cheiro forte e coloração não foram observados. Portanto, a mono-hidrogenação da fração C5 contendo os isoamilenos reativos é necessária para que o TAME produzido na reação de eterificação possa ser adicionado à gasolinaTAME was synthesized in liquid phase from refinery C5 cut and methanol using Amberlyst 15 as catalyst. The C5 stream contains mainly mono-olefins and, in a less amount, a diolefin, which have a high gum formation tendency. The main purpose of this research was to evaluate the effect of mono-hydrogenation of C5 cut on TAME synthesis. The hydrogenation step was carried out at 80 oC and 10 kgf/cm2 of H2

  18. Characterisation of 5-HT3C, 5-HT3D and 5-HT3E receptor subunits: evolution, distribution and function.

    Science.gov (United States)

    Holbrook, Joanna D; Gill, Catherine H; Zebda, Noureddine; Spencer, Jon P; Leyland, Rebecca; Rance, Kim H; Trinh, Han; Balmer, Gemma; Kelly, Fiona M; Yusaf, Shahnaz P; Courtenay, Nicola; Luck, Jane; Rhodes, Andrew; Modha, Sundip; Moore, Stephen E; Sanger, Gareth J; Gunthorpe, Martin J

    2009-01-01

    The 5-HT(3) receptor is a member of the 'Cys-loop' family of ligand-gated ion channels that mediate fast excitatory and inhibitory transmission in the nervous system. Current evidence points towards native 5-HT(3) receptors originating from homomeric assemblies of 5-HT(3A) or heteromeric assembly of 5-HT(3A) and 5-HT(3B). Novel genes encoding 5-HT(3C), 5-HT(3D), and 5-HT(3E) have recently been described but the functional importance of these proteins is unknown. In the present study, in silico analysis (confirmed by partial cloning) indicated that 5-HT(3C), 5-HT(3D), and 5-HT(3E) are not human-specific as previously reported: they are conserved in multiple mammalian species but are absent in rodents. Expression profiles of the novel human genes indicated high levels in the gastrointestinal tract but also in the brain, Dorsal Root Ganglion (DRG) and other tissues. Following the demonstration that these subunits are expressed at the cell membrane, the functional properties of the recombinant human subunits were investigated using patch clamp electrophysiology. 5-HT(3C), 5-HT(3D), and 5-HT(3E) were all non-functional when expressed alone. Co-transfection studies to determine potential novel heteromeric receptor interactions with 5-HT(3A) demonstrated that the expression or function of the receptor was modified by 5-HT(3C) and 5-HT(3E), but not 5-HT(3D). The lack of distinct effects on current rectification, kinetics or pharmacology of 5-HT(3A) receptors does not however provide unequivocal evidence to support a direct contribution of 5-HT(3C) or 5-HT(3E) to the lining of the ion channel pore of novel heteromeric receptors. The functional and pharmacological contributions of these novel subunits to human biology and diseases such as irritable bowel syndrome for which 5-HT(3) receptor antagonists have major clinical usage, therefore remains to be fully determined.

  19. The Variations and Trends of MODIS C5 & C6 Products’ Errors in the Recent Decade over the Background and Urban Areas of North China

    Directory of Open Access Journals (Sweden)

    Qi Zhang

    2016-09-01

    Full Text Available With ten-year (2004–2013 ground-based observations of Beijing Forest (BJF and Beijing City (BJC sites in North China, we validated the high-quality MODerate resolution Imaging Spectroradiometer (MODIS Collection 5 (C5 and Collection 6 (C6 Aerosol Optical Depth (AOD products’ precision and discussed the sensors degradation issues. The annual mean AOD and Angstrom exponent (α were 0.20 ± 0.02 and 0.83 ± 0.15 in the background over the past ten years, and they were 0.59 ± 0.07 and 1.13 ± 0.08 in the urban, respectively. Ground-based AOD had both slightly declining trends, with variations of 0.023 and 0.057 over the past decade in the background and urban, respectively. There were large differences among the eight kinds of MODIS AOD products (Terra vs. Aqua, C5 vs. C6, DT (Deep Target vs. DB (Deep Blue, and DTDB in the background and urban areas, but all the products’ monthly errors had larger variations in the spring and summer, and smaller ones in the autumn and winter. In the background, more than 62% of DT matchups for C5 and C6 products were within NASA’s expected error (EE envelope. In the urban, 69%~72% of C6 DB retrievals were falling within EE envelope. The new dataset named C6 DTDB had better performance in the background, whereas it overestimated by 37%~41% in the urban caused by surface reflectivity estimation error. The range of monthly average error varied from −0.21 to 0.28 in the background and from −0.63 to 0.48 in the urban. From the background to the urban areas, the retrieval errors of Terra and Aqua had slightly increased by 0.0023~0.0158 and 0.0011~0.0124 per year, respectively, which implied that the two MODIS instruments had degraded slowly.

  20. Experimental and Theoretical Studies of the Factors Affecting the Cycloplatination of the Chiral Ferrocenylaldimine (SC-[(η5-C5H5Fe{(η5-C5H4–C(H=N–CH(Me(C6H5}

    Directory of Open Access Journals (Sweden)

    Concepción López

    2014-11-01

    Full Text Available The study of the reactivity of the enantiopure ferrocenyl Schiff base (SC-[FcCH=N–CH(Me(C6H5] (1 (Fc = (η5-C5H5Fe(η5-C5H4 with cis-[PtCl2(dmso2] under different experimental conditions is reported. Four different types of chiral Pt(II have been isolated and characterized. One of them is the enantiomerically pure trans-(SC-[Pt{κ1-N[FcCH=N–CH(Me(C6H5]}Cl2(dmso] (2a in which the imine acts as a neutral N-donor ligand; while the other three are the cycloplatinated complexes: [Pt{κ2-C,N [(C6H4–N=CHFc]}Cl(dmso] (7a and the two diastereomers {(Sp,SC and (Rp,SC} of [Pt{κ2-C,N[(η5-C5H3–CH=N–{CH(Me(C6H5}]Fe(η5-C5H5}Cl(dmso] (8a and 9a, respectively. Isomers 7a-9a, differ in the nature of the metallated carbon atom [CPh (in 7a or CFc (in 8a and 9a] or the planar chirality of the 1,2-disubstituted ferrocenyl unit (8a and 9a. Reactions of 7a–9a with PPh3 gave [Pt{κ2-C,N[(C6H4–N=CHFc]}Cl(PPh3] (in 7b and the diastereomers (Sp,SC and (Rp,SC of [Pt{κ2-C,N[(η5-C5H3–CH=N–{CH(Me(C6H5}] Fe(η5-C5H5}Cl(PPh3] (8b and 9b, respectively. Comparative studies of the electrochemical properties and cytotoxic activities on MCF7 and MDA-MB231 breast cancer cell lines of 2a and cycloplatinated complexes 7b-9b are also reported. Theoretical studies based on DFT calculations have also been carried out in order to rationalize the results obtained from the cycloplatination of 1, the stability of the Pt(II complexes and their electrochemical properties.

  1. Effects of 60 MeV C5+ ion irradiation on PmT-PVC and p-TSA doped PoT-PVC blends

    International Nuclear Information System (INIS)

    Lakshmi, G.B.V.S.; Siddiqui, Azher M.; Ali, Vazid; Kulriya, Pawan K.; Zulfequar, M.

    2008-01-01

    Poly(m-toluidine) (PmT) and Poly(o-toluidine) (PoT) have been synthesized from derivatives of aniline (m-toluidine), (o-toluidine) monomers by chemical oxidative polymerization method. After polymerization, PoT powder was doped with p-toluene sulphonic acid (p-TSA) and the polymer powders were blended with poly vinyl chloride (PVC) to achieve PmT and p-TSA doped PoT dispersed films. XRD, FTIR and UV-visible studies were carried out to get their structural changes and optical information. These blends were irradiated by 60 MeV C 5+ ions with different fluences. Post Irradiation XRD, FTIR and UV-visible spectroscopy were also performed on all films. On p-TSA doped PoT-PVC blends dc-conductivity measurements are also carried out before and after irradiation. The results show structural modifications which lead to changes in optical and electrical properties

  2. Dynamic Monte Carlo transient analysis for the Organization for Economic Co-operation and Development Nuclear Energy Agency (OECD/NEA) C5G7-TD benchmark

    Energy Technology Data Exchange (ETDEWEB)

    Shaukat, Nadeem; Ryu, Min; Shim, Hyung Jin [Seoul National University, Seoul (Korea, Republic of)

    2017-08-15

    With ever-advancing computer technology, the Monte Carlo (MC) neutron transport calculation is expanding its application area to nuclear reactor transient analysis. Dynamic MC (DMC) neutron tracking for transient analysis requires efficient algorithms for delayed neutron generation, neutron population control, and initial condition modeling. In this paper, a new MC steady-state simulation method based on time-dependent MC neutron tracking is proposed for steady-state initial condition modeling; during this process, prompt neutron sources and delayed neutron precursors for the DMC transient simulation can easily be sampled. The DMC method, including the proposed time-dependent DMC steady-state simulation method, has been implemented in McCARD and applied for two-dimensional core kinetics problems in the time-dependent neutron transport benchmark C5G7-TD. The McCARD DMC calculation results show good agreement with results of a deterministic transport analysis code, nTRACER.

  3. CF3+ fragmentation by electron impact ionization of perfluoro-propyl-vinyl-ethers, C5F10O, in gas phase

    Science.gov (United States)

    Kondo, Yusuke; Ishikawa, Kenji; Hayashi, Toshio; Miyawaki, Yudai; Takeda, Keigo; Kondo, Hiroki; Sekine, Makoto; Hori, Masaru

    2015-04-01

    The gas phase fragmentations of perfluoro-propyl-vinyl ether (PPVE, C5F10O) are studied experimentally. Dominant fragmentations of PPVE are found to be the result of a dissociative ionization reaction, i.e., CF3+ via direct bond cleavage, and C2F3O- and C3F7O- via electron attachment. Regardless of the appearance energy of around 14.5 eV for the dissociative ionization of CF3+, the observed ion efficiency for the CF3+ ion was extremely large the order of 10-20 cm-2, compared with only 10-21 cm-2 for the other channels. PPVE characteristically generated CF3+ as the largest abundant ion are advantageous for use of feedstock gases in plasma etching processes.

  4. Synthesis of novel 1H-1,2,3-triazole tethered C-5 substituted uracil-isatin conjugates and their cytotoxic evaluation

    KAUST Repository

    Kumar, Kewal; Sagar, Sunil; Esau, Luke; Kaur, Mandeep; Kumar, Vipan

    2012-01-01

    The present manuscript describes the synthesis of uracil-isatin hybrids via azide-alkyne cycloadditions and their cytotoxic evaluation against three human cancer cell lines viz. HeLa (cervix), MCF-7 (breast) and DU145 (prostate) using MTT assay. The evaluation studies revealed the dependence of cytotoxicity on C-5 substituents of both uracil and isatin as well as the alkyl chain length with compounds 6g and 6k showing IC50 values 18.21 and 13.90 μM respectively against DU145 cell lines. Most of the synthesized conjugates exhibited considerable selectivity against MCF-7 and DU145 cell lines. © 2012 Elsevier Masson SAS. All rights reserved.

  5. Synthesis of novel 1H-1,2,3-triazole tethered C-5 substituted uracil-isatin conjugates and their cytotoxic evaluation

    KAUST Repository

    Kumar, Kewal

    2012-12-01

    The present manuscript describes the synthesis of uracil-isatin hybrids via azide-alkyne cycloadditions and their cytotoxic evaluation against three human cancer cell lines viz. HeLa (cervix), MCF-7 (breast) and DU145 (prostate) using MTT assay. The evaluation studies revealed the dependence of cytotoxicity on C-5 substituents of both uracil and isatin as well as the alkyl chain length with compounds 6g and 6k showing IC50 values 18.21 and 13.90 μM respectively against DU145 cell lines. Most of the synthesized conjugates exhibited considerable selectivity against MCF-7 and DU145 cell lines. © 2012 Elsevier Masson SAS. All rights reserved.

  6. The 1.1 Å resolution structure of a periplasmic phosphate-binding protein from Stenotrophomonas maltophilia: a crystallization contaminant identified by molecular replacement using the entire Protein Data Bank.

    Science.gov (United States)

    Keegan, Ronan; Waterman, David G; Hopper, David J; Coates, Leighton; Taylor, Graham; Guo, Jingxu; Coker, Alun R; Erskine, Peter T; Wood, Steve P; Cooper, Jonathan B

    2016-08-01

    During efforts to crystallize the enzyme 2,4-dihydroxyacetophenone dioxygenase (DAD) from Alcaligenes sp. 4HAP, a small number of strongly diffracting protein crystals were obtained after two years of crystal growth in one condition. The crystals diffracted synchrotron radiation to almost 1.0 Å resolution and were, until recently, assumed to be formed by the DAD protein. However, when another crystal form of this enzyme was eventually solved at lower resolution, molecular replacement using this new structure as the search model did not give a convincing solution with the original atomic resolution data set. Hence, it was considered that these crystals might have arisen from a protein impurity, although molecular replacement using the structures of common crystallization contaminants as search models again failed. A script to perform molecular replacement using MOLREP in which the first chain of every structure in the PDB was used as a search model was run on a multi-core cluster. This identified a number of prokaryotic phosphate-binding proteins as scoring highly in the MOLREP peak lists. Calculation of an electron-density map at 1.1 Å resolution based on the solution obtained with PDB entry 2q9t allowed most of the amino acids to be identified visually and built into the model. A BLAST search then indicated that the molecule was most probably a phosphate-binding protein from Stenotrophomonas maltophilia (UniProt ID B4SL31; gene ID Smal_2208), and fitting of the corresponding sequence to the atomic resolution map fully corroborated this. Proteins in this family have been linked to the virulence of antibiotic-resistant strains of pathogenic bacteria and with biofilm formation. The structure of the S. maltophilia protein has been refined to an R factor of 10.15% and an Rfree of 12.46% at 1.1 Å resolution. The molecule adopts the type II periplasmic binding protein (PBP) fold with a number of extensively elaborated loop regions. A fully dehydrated phosphate

  7. Site-specific conjugation and labelling of prostate antibody 7E11C5.3 (CYT-351) with technetium-99m

    International Nuclear Information System (INIS)

    Stalteri, M.A.; Mather, S.J.; Belinka, B.A.; Coughlin, D.J.; Chengazi, V.U.; Britton, K.E.

    1997-01-01

    Attachment of chelating agents to the sugar residues of antibodies for subsequent radiolabelling is an attractive approach since it may have less effect on the immunoreactivity than attachment through lysine residues, which are distributed throughout the antibody and may be present near the antigen binding site. We have attached a new hydrazide-linked chelator CYT-395 (Cytogen Corp., Princeton, N.J.) to the sugar residues of the anti-prostate monoclonal antibody 7E11C5.3 and optimised the conditions for labelling the conjugate with technetium-99m in order to compare the conjugate to 7E11C5.3 antibody labelled directly with technetium using a mercaptoethanol reduction technique. Labelling yields of 70%-90% were obtained at specific activities up to 2000 MBq/mg antibody. The stability of the technetium-labelled conjugate in plasma or to a challenge with 0.1 or 1.0 mM cysteine was similar to that of direct-labelled antibody. In nine patients with prostate cancer, the plasma clearance of the labelled conjugate followed a two-compartment model, with an average β-phase half-life of 31.4±3.9 h. The average urinary clearance at 24 h was 15.3±5.0% of the injected dose. In this group of patients there was no significant difference between the blood and urine clearance of the labelled conjugate, and the clearances of the direct-labelled antibody. (orig.). With 5 figs

  8. Identification and characterization of NDT 9513727 [N,N-bis(1,3-benzodioxol-5-ylmethyl)-1-butyl-2,4-diphenyl-1H-imidazole-5-methanamine], a novel, orally bioavailable C5a receptor inverse agonist.

    Science.gov (United States)

    Brodbeck, Robbin M; Cortright, Daniel N; Kieltyka, Andrzej P; Yu, Jianying; Baltazar, Carolyn O; Buck, Marianne E; Meade, Robin; Maynard, George D; Thurkauf, Andrew; Chien, Du-Shieng; Hutchison, Alan J; Krause, James E

    2008-12-01

    The complement system represents an innate immune mechanism of host defense that has three effector arms, the C3a receptor, the C5a receptor (C5aR), and the membrane attack complex. Because of its inflammatory and immune-enhancing properties, the biological activity of C5a and its classical receptor have been widely studied. Because specific antagonism of the C5aR could have therapeutic benefit without affecting the protective immune response, the C5aR continues to be a promising target for pharmaceutical research. The lack of specific, potent and orally bioavailable small-molecule antagonists has limited the clinical investigation of the C5aR. We report the discovery of NDT 9513727 [N,N-bis(1,3-benzodioxol-5-ylmethyl)-1-butyl-2,4-diphenyl-1H-imidazole-5-methanamine], a small-molecule, orally bioavailable, selective, and potent inverse agonist of the human C5aR. NDT 9513727 was discovered based on the integrated use of in vitro affinity and functional assays in conjunction with medicinal chemistry. NDT 9513727 inhibited C5a-stimulated responses, including guanosine 5'-3-O-(thio)triphosphate binding, Ca(2+) mobilization, oxidative burst, degranulation, cell surface CD11b expression and chemotaxis in various cell types with IC(50)s from 1.1 to 9.2 nM, respectively. In C5a competition radioligand binding experiments, NDT 9513727 exhibited an IC(50) of 11.6 nM. NDT 9513727 effectively inhibited C5a-induced neutropenia in gerbil and cynomolgus macaque in vivo. The findings suggest that NDT 9513727 may be a promising new entity for the treatment of human inflammatory diseases.

  9. Conversion of Syngas-Derived C2+ Mixed Oxygenates to C3-C5 Olefins over ZnxZryOz Mixed Oxides Catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Colin D.; Lebarbier, Vanessa M.; Flake, Matthew D.; Ramasamy, Karthikeyan K.; Kovarik, Libor; Bowden, Mark E.; Onfroy, Thomas; Dagle, Robert A.

    2016-04-01

    In this study we report on a ZnxZryOz mixed oxide type catalyst capable of converting a syngas-derived C2+ mixed oxygenate feedstock to isobutene-rich olefins. Aqueous model feed comprising of ethanol, acetaldehyde, acetic acid, ethyl acetate, methanol, and propanol was used as representative liquid product derived from a Rh-based mixed oxygenate synthesis catalyst. Greater than 50% carbon yield to C3-C5 mixed olefins was demonstrated when operating at 400-450oC and 1 atm. In order to rationalize formation of the products observed feed components were individually evaluated. Major constituents of the feed mixture (ethanol, acetaldehyde, acetic acid, and ethyl acetate) were found to produce isobutene-rich olefins. C-C coupling was also demonstrated for propanol feedstock - a minor constituent of the mixed oxygenate feed - producing branched C6 olefins, revealing scalability to alcohols higher than ethanol following an analogous reaction pathway. Using ethanol and propanol feed mixtures, cross-coupling reactions produced mixtures of C4, C5, and C6 branched olefins. The presence of H2 in the feed was found to facilitate hydrogenation of the ketone intermediates, thus producing straight chain olefins as byproducts. While activity loss from coking is observed complete catalyst regeneration is achieved by employing mild oxidation. For conversion of the mixed oxygenate feed a Zr/Zn ratio of 2.5 and a reaction temperature of 450oC provides the best balance of stability, activity, and selectivity. X-ray diffraction and scanning transmission electron microscopy analysis reveals the presence of primarily cubic phase ZrO2 and a minor amount of the monoclinic phase, with ZnO being highly dispersed in the lattice. The presence of ZnO appears to stabilize the cubic phase resulting in less monoclinic phase as the ZnO concentration increases. Infrared spectroscopy shows the mixed oxide acid sites are characterized as primarily Lewis type acidity. The direct relationship between

  10. Local expression of global forcing factors in Lower Cretaceous, Aptian carbon isotope segment C5: El Pujal Section, Organya Basin, Catalunya, Spain.

    Science.gov (United States)

    Socorro, J.; Maurrasse, F. J.

    2017-12-01

    During the Aptian, the semi-restricted Organya Basin accumulated sediments under quasi-continuous dysoxic conditions [1]. High resolution stable carbon isotope (δ13Corg) values for 71.27 m of interbedded limestones, argillaceous limestones and marlstones of the El Pujal sequence show relatively small variability (1.65‰) fluctuating between -25.09‰ and -23.44‰ with an average of -24.02‰. This pattern is consistent with values reported for other Tethyan sections for carbon isotope segment C5 [2]. The geochemical and petrographic results of the sequence, reveal periodic enrichment of redox sensitive trace elements (V, Cr, Co, Ni, Cu, Mo, U), biolimiting (P, Fe) and major elements (Al, Si, Ti) at certain levels concurrent with episodes of enhanced organic carbon preservation (TOC). Inorganic carbonate (TIC) dilution due to significant clay fluxes is also evident along these intervals as illustrated by the strong negative correlation with Al (r = -0.91). Microfacies characterized by higher pyrite concentration, impoverished benthic fauna and lower degree of bioturbation index (3) are in accord with geochemical proxies. When combined, these results suggest recurrent intermittent dysoxic conditions associated with episodic increases of terrigenous supplies by riverine fluxes, which are in agreement with results reported for the basal segment of the section (0-13.77m) [3]. Concurrently, δ13Corg values show a positive correlation with TIC (r = 0.50) and a negative correlation with TOC (r = -0.46), thus showing more negative values corresponding with intervals of highest terrestrial influences, which were previously correlated with higher inputs of higher chain (>nC25) n-alkanes [3]. Hence, the results highlight the local expression of the δ13Corg signal related to higher inputs of terrestrial vegetation linked with lower δ13Corg values modulating the global signature of segment C5. References: [1] Sanchez-Hernandez & Maurrasse, 2016. Palaeo3 441; [2] Menegatti

  11. Energetics of the interaction of the antitumour agent titanocene dichloride with glycine: enthalpy of formation of [Ti(η5-C5H5)2(OOCCH2NH3)2]Cl2

    International Nuclear Information System (INIS)

    Nunes, Paulo M.; Minas da Piedade, Manuel E.

    2004-01-01

    The standard molar enthalpy of formation of [Ti(η 5 -C 5 H 5 ) 2 (OOCCH 2 NH 3 ) 2 ]Cl 2 in the crystalline state, at T=298.15 K, was determined as Δ f H m 0 {[Ti(η 5 -C 5 H 5 ) 2 (OOCCH 2 NH 3 ) 2 ]Cl 2 , cr}=-(1447.6 ± 8.1) kJ · mol -1 , by reaction-solution calorimetry. A discussion of the energetics of the direct interaction of the antitumour agent Ti(η 5 -C 5 H 5 ) 2 Cl 2 with glycine is also presented

  12. Haldane-gap excitations in the low-Hc one-dimensional quantum antiferromagnet Ni(C5D14N2)2N3(PF6)

    International Nuclear Information System (INIS)

    Zheludev, A.; Chen, Y.; Broholm, C. L.; Honda, Z.; Katsumata, K.

    2001-01-01

    Inelastic neutron scattering on deuterated single-crystal samples is used to study Haldane-gap excitations in the new S=1 one-dimensional quantum antiferromagnet Ni(C 5 D 14 N 2 ) 2 N 3 (PF 6 ), that was recently recognized as an ideal model system for high-field studies. The Haldane gap energies Δ x =0.42(3) meV, Δ y =0.52(6) meV, and Δ z =1.9(1) meV, for excitations polarized along the a, b, and c crystallographic axes, respectively, are measured. The dispersion relation is studied for momentum transfers both along and perpendicular to the chains' direction. The in-chain exchange constant J=2.8 meV is found to be much larger than interchain coupling, J y =1.8(4)x10 -3 meV and J x =4(3)x10 -4 meV, along the b and a axes, respectively. The results are discussed in the context of future experiments in high magnetic fields

  13. Distal nerve transfer versus supraclavicular nerve grafting: comparison of elbow flexion outcome in neonatal brachial plexus palsy with C5-C7 involvement.

    Science.gov (United States)

    Heise, Carlos O; Siqueira, Mario G; Martins, Roberto S; Foroni, Luciano H; Sterman-Neto, Hugo

    2017-09-01

    Ulnar and median nerve transfers to arm muscles have been used to recover elbow flexion in infants with neonatal brachial plexus palsy, but there is no direct outcome comparison with the classical supraclavicular nerve grafting approach. We retrospectively analyzed patients with C5-C7 neonatal brachial plexus palsy submitted to nerve surgery and recorded elbow flexion recovery using the active movement scale (0-7) at 12 and 24 months after surgery. We compared 13 patients submitted to supraclavicular nerve grafting with 21 patients submitted to distal ulnar or median nerve transfer to biceps motor branch. We considered elbow flexion scores of 6 or 7 as good results. The mean elbow flexion score and the proportion of good results were better using distal nerve transfers than supraclavicular grafting at 12 months (p nerve grafting at 12 months showed good elbow flexion recovery after ulnar nerve transfers. Distal nerve transfers provided faster elbow flexion recovery than supraclavicular nerve grafting, but there was no significant difference in the outcome after 24 months of surgery. Patients with failed supraclavicular grafting operated early can still benefit from late distal nerve transfers. Supraclavicular nerve grafting should remain as the first line surgical treatment for children with neonatal brachial plexus palsy.

  14. Pharmacokinetics of the FO23C5 anti-CEA antibody fragment labelled with 99Tcm and 111In: a comparison in patients

    International Nuclear Information System (INIS)

    Hnatowich, D.J.; Mardirossian, G.; Rusckowski, M.; Roy, S.; Busche, H.; Griffin, T.W.; Brill, A.B.

    1993-01-01

    The FO23C5 anti-carcinoembryonic antigen (CEA) F(ab') 2 antibody was radiolabelled with sup(111)In via diethylenetriaminepentaacetic acid (DTPA) and directly with 99 Tc m by stannous ion and mercaptoethanol antibody reduction to compare the pharmacokinetics of these three agents. Four patients received 15 mCi 99 Tc m -Fab' 1 week before receiving 1 mCi 111 In-F(ab') 2 . Five additional patients received only the 99 Tc m -Fab'. The biodistribution of 99 Tc m was as expected for a labelled Fab' fragment: relative to 111 In, 99 Tc m cleared rapidly from circulation and into kidneys and urine. Liver levels of 111 In and 99 Tc m were surprisingly similar at 1 day although initial 111 In levels were lower and increased while 99 Tc m levels were higher and decreased. Spleen levels were also similar. In 4/9 patients receiving 99 Tc m , hepatobiliary clearance was observed at levels which could confuse interpretation whereas this mode of clearance was observed in only 1/4 patients receiving 111 In. Image quality was superior with 111 In versus 99 Tc m at 1 day postadministration as judged by counting rates and background activity whereas the opposite was true at 2-3 h postadministration. (author)

  15. The CPT1C 5'UTR contains a repressing upstream open reading frame that is regulated by cellular energy availability and AMPK.

    Directory of Open Access Journals (Sweden)

    Ines Lohse

    Full Text Available BACKGROUND: Translational control is utilized as a means of regulating gene expression in many species. In most cases, posttranscriptional regulatory mechanisms play an important role in stress response pathways and can lead to dysfunctional physiology if blocked by mutations. Carnitine Palmitoyltransferase 1 C (CPT1C, the brain-specific member of the CPT 1 family, has previously been shown to be involved in regulating metabolism in situations of energy surplus. PRINCIPAL FINDINGS: Sequence analysis of the CPT1C mRNA revealed that it contains an upstream open reading frame (uORF in the 5' UTR of its mRNA. Using CPT1C 5' UTR/luciferase constructs, we investigated the role of the uORF in translational regulation. The results presented here show that translation from the CPT1C main open reading frame (mORF is repressed by the presence of the uORF, that this repression is relieved in response to specific stress stimuli, namely glucose deprivation and palmitate-BSA treatment, and that AMPK inhibition can relieve this uORF-dependent repression. SIGNIFICANCE: The fact that the mORF regulation is relieved in response to a specific set of stress stimuli rather than general stress response, hints at an involvement of CPT1C in cellular energy-sensing pathways and provides further evidence for a role of CPT1C in hypothalamic regulation of energy homeostasis.

  16. Physicochemical properties of manganese dioxide synthesized using C2–C5 alcohols as reducing agents and their catalytic activities for CO oxidation

    KAUST Repository

    Lee, Young-Ho

    2015-09-26

    MnO2 catalysts were synthesized in an aqueous solution of KMnO4 and C2–C5 alcohols using a simple redox method at room temperature. The crystalline structure of all samples was δ-MnO2 after being calcined at 300 °C. However, other physicochemical properties of the samples varied depending on the symmetry of the alcohols used. For the catalytic oxidation of CO, MnO2 catalysts prepared with 1° alcohols performed better than the samples prepared in 2° alcohols. Catalytic activities were correlated to the quantity of labile oxygen species of the catalysts. In CO-TPD analysis, the relative area of desorbed radical dotCO2, which is the product of the reaction between adsorbed CO and lattice oxygen species, becomes larger for MnO2 prepared with 1° alcohols than with 2° alcohols. These results were primarily resulted from the innate hydrogen dissociation behavior of alcohol in solution. The pKa was found to be an important factor in determining the physicochemical properties and catalytic activity toward CO oxidation of MnO2.

  17. Proteolysis of complement factors iC3b and C5 by the serine protease prostate-specific antigen in prostatic fluid and seminal plasma.

    Science.gov (United States)

    Manning, Michael L; Williams, Simon A; Jelinek, Christine A; Kostova, Maya B; Denmeade, Samuel R

    2013-03-15

    Prostate-specific Ag (PSA) is a serine protease that is expressed exclusively by normal and malignant prostate epithelial cells. The continued high-level expression of PSA by the majority of men with both high- and low-grade prostate cancer throughout the course of disease progression, even in the androgen-ablated state, suggests that PSA has a role in the pathogenesis of disease. Current experimental and clinical evidence suggests that chronic inflammation, regardless of the cause, may predispose men to prostate cancer. The responsibility of the immune system in immune surveillance and eventually tumor progression is well appreciated but not completely understood. In this study, we used a mass spectrometry-based evaluation of prostatic fluid obtained from diseased prostates after removal by radical prostatectomy to identify potential immunoregulatory proteins. This analysis revealed the presence of Igs and the complement system proteins C3, factor B, and clusterin. Verification of these findings by Western blot confirmed the high-level expression of C3 in the prostatic fluid and the presence of a previously uncharacterized C-terminal C3 cleavage product. Biochemical analysis of this C3 cleavage fragment revealed a putative PSA cleavage site after tyrosine-1348. Purified PSA was able to cleave iC3b and the related complement protein C5. These results suggest a previously uncharacterized function of PSA as an immunoregulatory protease that could help to create an environment hospitable to malignancy through proteolysis of the complement system.

  18. Physicochemical properties of manganese dioxide synthesized using C2–C5 alcohols as reducing agents and their catalytic activities for CO oxidation

    KAUST Repository

    Lee, Young-Ho; Park, Jung-Hyun; Shin, Chae-Ho

    2015-01-01

    MnO2 catalysts were synthesized in an aqueous solution of KMnO4 and C2–C5 alcohols using a simple redox method at room temperature. The crystalline structure of all samples was δ-MnO2 after being calcined at 300 °C. However, other physicochemical properties of the samples varied depending on the symmetry of the alcohols used. For the catalytic oxidation of CO, MnO2 catalysts prepared with 1° alcohols performed better than the samples prepared in 2° alcohols. Catalytic activities were correlated to the quantity of labile oxygen species of the catalysts. In CO-TPD analysis, the relative area of desorbed radical dotCO2, which is the product of the reaction between adsorbed CO and lattice oxygen species, becomes larger for MnO2 prepared with 1° alcohols than with 2° alcohols. These results were primarily resulted from the innate hydrogen dissociation behavior of alcohol in solution. The pKa was found to be an important factor in determining the physicochemical properties and catalytic activity toward CO oxidation of MnO2.

  19. Ionic conduction in 70-MeV C5+-ion-irradiated poly(vinylidenefluoride- co-hexafluoropropylene)-based gel polymer electrolytes

    International Nuclear Information System (INIS)

    Saikia, D.; Kumar, A.; Singh, F.; Avasthi, D.K.; Mishra, N.C.

    2005-01-01

    In an attempt to increase the Li + -ion diffusivity, poly(vinylidenefluoride-co-hexafluoropropylene)-(propylene carbonate+diethyl carbonate)-lithium perchlorate gel polymer electrolyte system has been irradiated with 70-MeV C 5+ -ion beam of nine different fluences. Swift heavy-ion irradiation shows enhancement in ionic conductivity at lower fluences and decrease in ionic conductivity at higher fluences with respect to unirradiated gel polymer electrolyte films. Maximum room-temperature (303 K) ionic conductivity is found to be 2x10 -2 S/cm after irradiation with a fluence of 10 11 ions/cm 2 . This interesting result could be attributed to the fact that for a particular ion beam with a given energy, a higher fluence provides critical activation energy for cross linking and crystallization to occur, which results in the decrease in ionic conductivity. X-ray-diffraction results show decrease in the degree of crystallinity upon ion irradiation at low fluences (≤10 11 ions/cm 2 ) and increase in crystallinity at higher fluences (>10 11 ions/cm 2 ). Analysis of Fourier-transform infrared spectroscopy results suggests the bond breaking at a fluence of 5x10 9 ions/cm 2 and cross linking at a fluence of 10 12 ions/cm 2 and corroborate conductivity and x-ray-diffraction results. Scanning electron micrographs exhibit increased porosity of the polymer electrolyte after ion irradiation

  20. SYNTHESIS AND CHARACTERIZATION OF (MU-5-C5ME5)2TI(R)CL (R = ME, ET, NORMAL-PR, CH=CH2, PH, O-NORMAL-PR) AND THEIR SALT METATHESIS REACTIONS - THERMAL-DECOMPOSITION PATHWAYS OF (MU-5-C5ME5)2TI(ME)R' (R' = ET, CH=CH2, PH, CH2PH)

    NARCIS (Netherlands)

    LUINSTRA, GA; TEUBEN, JH

    Complexes Cp*2Ti(R)Cl (Cp* = eta-5-C5Me5; R = Me (1), Et (2), n-Pr (3), CH=CH2 (4), Ph (5), O-n-Pr (6)) have been prepared by oxidation Of CP*2TiR with lead dichloride. Not every compound Cp*2Ti(R)Cl was accessible and for R = CH2CMe3 and CH2Ph reduction to Cp*2TiCl and R. was observed. Homolysis of

  1. Synthesis and Characterization of (η5-C5Me5)2Ti(R)Cl (R = Me, Et, n-Pr, CH=CH2, Ph, O-n-Pr) and Their Salt Metathesis Reactions. Thermal Decomposition Pathways of (η5-C5Me5)2Ti(Me)R' (R' = Et, CH=CH2, Ph, CH2Ph)

    NARCIS (Netherlands)

    Luinstra, Gerrit A.; Teuben, Jan H.

    1992-01-01

    Complexes Cp*2Ti(R)Cl (Cp* = η5-C5Me5; R = Me (1), Et (2), n-Pr (3), CH=CH2 (41, Ph (5), O-n-Pr (6)) have been prepared by oxidation of Cp*2TiR with lead dichloride. Not every compound Cp*2Ti(R)Cl was accessible and for R = CH2CMe3 and CH2Ph reduction to Cp*2TiCl and R· was observed. Homolysis of

  2. OXIDATIVE ALKYLATION OF (ETA-5-C5ME5)2TIR (R=CL, ME, ET, CH=CH2, PH, OME, N=C(H)TERT-BU) TO (ETA-5-C5ME5)2TI(ME)R BY GROUP-12 ORGANOMETALLIC COMPOUNDS MME2

    NARCIS (Netherlands)

    LUINSTRA, GA; TEUBEN, JH

    1991-01-01

    Oxidative alkylation of Cp*2TiX (Cp*: eta-5-C5Me5; X = OMe, Cl, N = C(H)tBu) and Cp*2TiMe by CdMe2 or ZnMe2 gives diamagnetic Cp*2Ti(Me)X and Cp*2TiMe2 respectively, and cadmium or zinc. The reactions of Cp*2TiR (R = Et, CH = CH2, Ph) with MMe2 (M = Cd, Zn) give statistical mixtures of Cp*2Ti(Me)R,

  3. Encapsulation of a trinuclear silver(I) cluster by two imido-nitrido metalloligands [{Ti(eta5-C5Me5)(micro-NH)}3(micro3-N)].

    Science.gov (United States)

    Martín, Avelino; Martínez-Espada, Noelia; Mena, Miguel; Yélamos, Carlos

    2007-07-28

    Treatment of the metalloligand [{Ti(eta(5)-C(5)Me(5))(micro-NH)}(3)(micro(3)-N)] with silver(i) trifluoromethanesulfonate in different molar ratios gives the ionic compounds [Ag{(micro(3)-NH)(3)Ti(3)(eta(5)-C(5)Me(5))(3)(micro(3)-N)}(2)][O(3)SCF(3)] and [Ag{(micro(3)-NH)(3)Ti(3)(eta(5)-C(5)Me(5))(3)(micro(3)-N)}][O(3)SCF(3)] or the triangular silver cluster [(CF(3)SO(2)O)(3)Ag(3){(micro(3)-NH)(3)Ti(3)(eta(5)-C(5)Me(5))(3)(micro(3)-N)}(2)] in which each face is capped by a metalloligand.

  4. SYNTHESIS OF NEW BIS(CYCLOPENTADIENYL)YTTRIUM COMPLEXES WITH ETHER FUNCTIONALIZED CYCLOPENTADIENYL LIGANDS - CRYSTAL-STRUCTURE OF [(C(5)H(4)CH(2)CH(2)OME)(2)Y(MU-H)(2)BH2

    NARCIS (Netherlands)

    LASKE, DA; DUCHATEAU, R; TEUBEN, JH; SPEK, AL

    1993-01-01

    Treatment of C(5)H(4)CH(2)CH(2)OMe.Li(TMEDA) (TMEDA = N, N, N', N' tetramethylethylenediamine) with half an equivalent of YCl3(THF)(3.5) in toluene afforded the salt- and solvent-free dimeric biscyclopentadienyl yttrium chloride [(C(5)H(4)CH(2)CH(2)OMe)(2)Y-(mu-Cl)](2) (1). Reaction of 1 with one

  5. Complement factor 5 (C5) p.A252T mutation is prevalent in, but not restricted to, sub-Saharan Africa: implications for the susceptibility to meningococcal disease.

    Science.gov (United States)

    Franco-Jarava, C; Comas, D; Orren, A; Hernández-González, M; Colobran, R

    2017-08-01

    Complement C5 deficiency (C5D) is a rare primary immunodeficiency associated with recurrent infections, particularly meningitis, by Neisseria species. To date, studies to elucidate the molecular basis of hereditary C5D have included fewer than 40 families, and most C5 mutations (13 of 17) have been found in single families. However, the recently described C5 p.A252T mutation is reported to be associated with approximately 7% of meningococcal disease cases in South Africa. This finding raises the question of whether the mutation may be prevalent in other parts of Africa or other continental regions. The aim of this study was to investigate the prevalence of C5 p.A252T in Africa and other regions and discuss the implications for prophylaxis against meningococcal disease. In total, 2710 samples from healthy donors within various populations worldwide were analysed by quantitative polymerase chain reaction (qPCR) assay to detect the C5 p.A252T mutation. Eleven samples were found to be heterozygous for p.A252T, and nine of these samples were from sub-Saharan African populations (allele frequency 0·94%). Interestingly, two other heterozygous samples were from individuals in populations outside Africa (Israel and Pakistan). These findings, together with data from genomic variation databases, indicate a 0·5-2% prevalence of the C5 p.A252T mutation in heterozygosity in sub-Saharan Africa. Therefore, this mutation may have a relevant role in meningococcal disease susceptibility in this geographical area. © 2017 British Society for Immunology.

  6. Concentrations of higher dicarboxylic acids C5–C13 in fresh snow samples collected at the High Alpine Research Station Jungfraujoch during CLACE 5 and 6

    Directory of Open Access Journals (Sweden)

    K. Sieg

    2009-03-01

    Full Text Available Samples of freshly fallen snow were collected at the high alpine research station Jungfraujoch (Switzerland in February and March 2006 and 2007, during the Cloud and Aerosol Characterization Experiments (CLACE 5 and 6. In this study a new technique has been developed and demonstrated for the measurement of organic acids in fresh snow. The melted snow samples were subjected to solid phase extraction and resulting solutions analysed for organic acids by HPLC-MS-TOF using negative electrospray ionization. A series of linear dicarboxylic acids from C5 to C13 and phthalic acid, were identified and quantified. In several samples the biogenic acid pinonic acid was also observed. In fresh snow the median concentration of the most abundant acid, adipic acid, was 0.69 μg L−1 in 2006 and 0.70 μg L−1 in 2007. Glutaric acid was the second most abundant dicarboxylic acid found with median values of 0.46 μg L−1 in 2006 and 0.61 μg L−1 in 2007, while the aromatic acid phthalic acid showed a median concentration of 0.34 μg L−1 in 2006 and 0.45 μg L−1 in 2007. The concentrations in the samples from various snowfall events varied significantly, and were found to be dependent on the back trajectory of the air mass arriving at Jungfraujoch. Air masses of marine origin showed the lowest concentrations of acids whereas the highest concentrations were measured when the air mass was strongly influenced by boundary layer air.

  7. Standard Molar Enthalpy of Formation of RE(C5H8NS2)3(C12H8N2)

    Institute of Scientific and Technical Information of China (English)

    Meng Xiangxin; Shuai Qi; Chen Sanping; Xie Gang; Gao Shengli; Shi Qizhen

    2005-01-01

    Four solid ternary complexes of RE (C5H8NS2)3(C12H8N2) (RE=Eu, Gd, Tb, Dy) were synthesized in absolute ethanol by rare earth chloride low hydrate with the mixed ligands of ammonium pyrrolidinedi-thiocarbamate (APDC) and 1, 10-phenanthroline*H2O (o-phen*H2O) in the ordinary laboratory atmosphere without any cautions against moisture or air sensitivity. IR spectra of the complexes show that the RE3+ coordinated with six sulfur atoms of three PDC- and two nitrogen atoms of o-phen*H2O. It was assumed that the coordination number of RE3+ is eight. The constant-volume combustion energies of the complexes, ΔcU, were determined as (-16937.88±9.79 ), (-17588.79±8.62 ), (-17747.14±8.25 ) and (-17840.37±8.87 ) kJ*mol-1, by a precise rotating-bomb calorimeter at 298.15 K. Its standard molar enthalpies of combustion, ΔcHθm, and standard molar enthalpies of formation, ΔfHθm, were calculated as (-16953.37±9.79), (-17604.28±8.62), (-17762.63±8.25), (-17855.86±8.87) kJ*mol-1 and (-857.04±10.52), (-282.43±9.58), (-130.08±9.13), (-55.75±9.83) kJ*mol-1.

  8. Dual Inhibition of AChE and BChE with the C-5 Substituted Derivative of Meldrum’s Acid: Synthesis, Structure Elucidation, and Molecular Docking Studies

    Directory of Open Access Journals (Sweden)

    Haroon Mehfooz

    2017-07-01

    Full Text Available Alzheimer’s disease (AD lies in the category of those diseases which are still posing challenges to medicinal chemists, and the search for super-effective drugs for the treatment of AD is a work in progress. The inhibition of cholinesterase is considered a viable strategy to enhance the level of acetylcholine in the brain. The C-5 substituted derivative of Meldrum’s acid was synthesized and screened against acetylcholinesterase (AChE and butyrylcholinesterase (BChE enzyme inhibition activity. The simple and unique structure of synthesized derivative 3 was found to be good for the dual inhibition of both enzymes (AChE and BChE. 2,2-Dimethyl-5-(([2-(trifluoromethyl phenyl]aminomethylidene-1,3-dioxane-4,6-dione (3 showed significant inhibition against AChE, with an IC50 value of 1.13 ± 0.03 µ M (Standard Neostigmine 22.2 ± 3.2 µM, and moderate inhibition against BChE, with an IC50 value of 2.12 ± 1.22 µM (Standard Neostigmine 49.6 ± 6.11 µM. The structural insights reveal that compound 3 possesses intriguing reactive groups, which can potentially evoke the non-covalent interactions and possibly assist by binding in the active site of the target protein. Docking simulations revealed that the compound 3 showed binding inside the active site gorges of both AChE and BChE. An excellent agreement was obtained, as the best docked poses showed important binding features mostly based on interactions due to oxygen atoms and the aromatic moieties of the compound. The docking computations coupled with the experimental findings ascertained that the compound 3 can serve as a scaffold for the dual inhibitors of the human acetylcholine esterases.

  9. Enthalpies of ligand substitution for [Mo(η5C5H5)(CO)2(NO)] – The role of π-bonding effects in metal–ligand bond strengths

    International Nuclear Information System (INIS)

    Majumdar, Subhojit; Captain, Burjor; Cazin, Catherine S.J.; Nolan, Steven P.; Hoff, Carl D.

    2014-01-01

    Graphical abstract: - Highlights: • Enthalpies of ligand substitution are measured for Mo(C 5 H 5 )(CO) 2 (NO). • Phosphines and N-heterocyclic carbenes are stronger ligands and displace CO. • Backbonding to π ∗ orbitals is an important part of complex stability. • FTIR studies show shifts to lower wavenumbers of ν-CO and ν-NO. • Structural studies show lengthening of the C-O and N-O bonds. - Abstract: Enthalpies of ligand substitution for [Mo(η 5 -C 5 H 5 )(CO) 2 (NO)] producing [Mo(η 5 -C 5 H 5 )Mo(CO)(L)(NO)] have been measured by solution calorimetry at 30 °C in THF for L = P(OMe) 3 2 2 Ph 3 (SIPr = 1,3-bis(2,6-bis(diisopropylphenyl)imidazolinylidene; IPr = 1,3-bis(2,6-bis(diisopropylphenyl)-imidazol-2-ylidene)). The accepting metal fragment [Mo(η 5 -C 5 H 5 )(CO)(NO)] has a vacant site containing strongly π-accepting carbonyl and nitrosyl ligands and this is shown to influence the stability of the product complex. Infrared studies of both ν CO and ν NO show that metal-to-ligand backbonding increases in the order P(OMe) 3 3 5 -C 5 H 5 )(CO)(IPr)(NO)] and [Mo(η 5 -C 5 H 5 )(CO)(SIPr)(NO)] are reported

  10. Tinnunculite, C5H4N4O3 · 2H2O: Occurrences on the Kola Peninsula and Redefinition and Validation as a Mineral Species

    Science.gov (United States)

    Pekov, I. V.; Chukanov, N. V.; Yapaskurt, V. O.; Belakovskiy, D. I.; Lykova, I. S.; Zubkova, N. V.; Shcherbakova, E. P.; Britvin, S. N.; Chervonnyi, A. D.

    2017-12-01

    Based on a study of samples found in the Khibiny (Mt. Rasvumchorr: the holotype) and Lovozero (Mts Alluaiv and Vavnbed) alkaline complexes on the Kola Peninsula, Russia, tinnunculite was approved by the IMA Commission on New Minerals, Nomenclature, and Classification as a valid mineral species (IMA no. 2015-02la) and, taking into account a revisory examination of the original material from burnt dumps of coal mines in the southern Urals, it was redefined as crystalline uric acid dihydrate (UAD), C5H4N4O3 · 2H2O. Tinnunculite is poultry manure mineralized in biogeochemical systems, which could be defined as "guano microdeposits." The mineral occurs as prismatic or tabular crystals up to 0.01 × 0.1 × 0.2 mm in size and clusters of them, as well as crystalline or microglobular crusts. Tinnunculite is transparent or translucent, colorless, white, yellowish, reddish or pale lilac. Crystals show vitreous luster. The mineral is soft and brittle, with a distinct (010) cleavage. D calc = 1.68 g/cm3 (holotype). Tinnunculite is optically biaxial (-), α = 1.503(3), β = 1.712(3), γ = 1.74(1), 2 V obs = 40(10)°. The IR spectrum is given. The chemical composition of the holotype sample (electron microprobe data, content of H is calculated by UAD stoichiometry) is as follows, wt %: 37.5 O, 28.4 C, 27.0 N, 3.8 Hcalc, total 96.7. The empirical formula calculated on the basis of (C + N+ O) = 14 apfu is: C4.99H8N4.07O4.94. Tinnunculite is monoclinic, space group (by analogy with synthetic UAD) P21/ c. The unit cell parameters of the holotype sample (single crystal XRD data) are a = 7.37(4), b = 6.326(16), c = 17.59(4) Å, β = 90(1)°, V = 820(5) Å3, Z = 4. The strongest reflections in the XRD pattern ( d, Å- I[ hkl]) are 8.82-84[002], 5.97-15[011], 5.63-24[102̅, 102], 4.22-22[112], 3.24-27[114̅,114], 3.18-100[210], 3.12-44[211̅, 211], 2.576-14[024].

  11. A new and general method for the preparation of novel II-heterocyclic derivatives of ruthenium [C5Me5Ru (η6-arene)]X (arene = benzene, thiophene, 3-methylthiophene, benzothiophene, pyridine, 2.6 and 3.5-lutidine, quinoline, acridine). X-ray crystal structure of [(C5Me5)2Ru2Cl2(pyridine)2] PF6

    International Nuclear Information System (INIS)

    Chaudret, B.; Jalon, F.; Perez-Manrique, M.; Lahoz, F.; Plou, F.J.

    1990-01-01

    Zinc reduction of (Cp*RuCl 2 ) n (Cp* = C 5 Me 5 ) in acetone or THF followed by addition of 1 equivalent of an arene or aromatic heterocycle leads to compounds of general formulation [Cp* Ru(arene)]X (X = Cl, BF 4 ). Coordination of benzene is rapid and competes successfully with any other arene. Thiophene and 3-methylthiophene give stable π adducts whereas benzothiophene is coordinated through the benzene not through the heterocyclic ring. 2.6 and 3.5-lutidine coordinate through the ring, thus demonstrating an electronic rather than steric stabilization. Again, quinoline and acridine coordinate through the benzene ring. Pyridine gives an unstable π adduct in THF. A paramagnetic mixed-valence species, byproduct of the reaction in THF, has been characterized by an X-ray crystal structure determination. Crystals are triclinic, space group P-1

  12. Compositions, thermodynamic properties, and transport coefficients of high-temperature C5F10O mixed with CO2 and O2 as substitutes for SF6 to reduce global warming potential

    Directory of Open Access Journals (Sweden)

    Linlin Zhong

    2017-07-01

    Full Text Available C5F10O has recently been found to be a very promising alternative to SF6. This paper is devoted to the investigation of compositions, thermodynamic properties, and transport coefficients of high-temperature C5F10O mixed with CO2 and O2. Firstly, the partition functions and enthalpies of formation for a few molecules (CxFy and CxFyO which are likely to exist in the mixtures, are calculated based on the G4(MP2 theory. The isomers of the above molecules are selected according to their Gibbs energy. The compositions of C5F10O-CO2-O2 mixtures are then determined using the minimization of the Gibbs free energy. Next, the thermodynamic properties (mass density, specific enthalpy, and specific heat are derived from the previously calculated compositions. Lastly, the transport coefficients (electrical conductivity, viscosity, and thermal conductivity are calculated based on Chapman-Enskog method. It is found that, as an arc quenching gas, C5F10O could not recombine into itself with the temperature decreasing down to room temperature after the arc extinction. Besides, the key species at room temperature are always CF4, CO2, and C4F6 if graphite is not considered. When taken into account, graphite will replace C4F6 as one of the dominate particles. The mixing of CO2 with C5F10O plasma significantly affects the thermodynamic properties (e.g. vanishing and/or shifting of the peaks in specific heat and transport coefficients (e.g. reducing viscosity and changing the number of peaks in thermal conductivity, while the addition of O2 with C5F10O-CO2 mixtures has no remarkable influence on both thermodynamic and transport properties.

  13. Compositions, thermodynamic properties, and transport coefficients of high-temperature C5F10O mixed with CO2 and O2 as substitutes for SF6 to reduce global warming potential

    Science.gov (United States)

    Zhong, Linlin; Rong, Mingzhe; Wang, Xiaohua; Wu, Junhui; Han, Guiquan; Han, Guohui; Lu, Yanhui; Yang, Aijun; Wu, Yi

    2017-07-01

    C5F10O has recently been found to be a very promising alternative to SF6. This paper is devoted to the investigation of compositions, thermodynamic properties, and transport coefficients of high-temperature C5F10O mixed with CO2 and O2. Firstly, the partition functions and enthalpies of formation for a few molecules (CxFy and CxFyO) which are likely to exist in the mixtures, are calculated based on the G4(MP2) theory. The isomers of the above molecules are selected according to their Gibbs energy. The compositions of C5F10O-CO2-O2 mixtures are then determined using the minimization of the Gibbs free energy. Next, the thermodynamic properties (mass density, specific enthalpy, and specific heat) are derived from the previously calculated compositions. Lastly, the transport coefficients (electrical conductivity, viscosity, and thermal conductivity) are calculated based on Chapman-Enskog method. It is found that, as an arc quenching gas, C5F10O could not recombine into itself with the temperature decreasing down to room temperature after the arc extinction. Besides, the key species at room temperature are always CF4, CO2, and C4F6 if graphite is not considered. When taken into account, graphite will replace C4F6 as one of the dominate particles. The mixing of CO2 with C5F10O plasma significantly affects the thermodynamic properties (e.g. vanishing and/or shifting of the peaks in specific heat) and transport coefficients (e.g. reducing viscosity and changing the number of peaks in thermal conductivity), while the addition of O2 with C5F10O-CO2 mixtures has no remarkable influence on both thermodynamic and transport properties.

  14. Compositions, thermodynamic properties, and transport coefficients of high-temperature C5F10O mixed with CO2 and O2 as substitutes for SF6 to reduce global warming potential

    OpenAIRE

    Linlin Zhong; Mingzhe Rong; Xiaohua Wang; Junhui Wu; Guiquan Han; Guohui Han; Yanhui Lu; Aijun Yang; Yi Wu

    2017-01-01

    C5F10O has recently been found to be a very promising alternative to SF6. This paper is devoted to the investigation of compositions, thermodynamic properties, and transport coefficients of high-temperature C5F10O mixed with CO2 and O2. Firstly, the partition functions and enthalpies of formation for a few molecules (CxFy and CxFyO) which are likely to exist in the mixtures, are calculated based on the G4(MP2) theory. The isomers of the above molecules are selected according to their Gibbs en...

  15. Zoledronate complexes. III. Two zoledronate complexes with alkaline earth metals: [Mg(C(5)H(9)N(2)O(7)P(2))(2)(H(2)O)(2)] and [Ca(C(5)H(8)N(2)O(7)P(2))(H(2)O)](n).

    Science.gov (United States)

    Freire, Eleonora; Vega, Daniel R; Baggio, Ricardo

    2010-06-01

    Diaquabis[dihydrogen 1-hydroxy-2-(imidazol-3-ium-1-yl)ethylidene-1,1-diphosphonato-kappa(2)O,O']magnesium(II), [Mg(C(5)H(9)N(2)O(7)P(2))(2)(H(2)O)(2)], consists of isolated dimeric units built up around an inversion centre and tightly interconnected by hydrogen bonding. The Mg(II) cation resides at the symmetry centre, surrounded in a rather regular octahedral geometry by two chelating zwitterionic zoledronate(1-) [or dihydrogen 1-hydroxy-2-(imidazol-3-ium-1-yl)ethylidene-1,1-diphosphonate] anions and two water molecules, in a pattern already found in a few reported isologues where the anion is bound to transition metals (Co, Zn and Ni). catena-Poly[[aquacalcium(II)]-mu(3)-[hydrogen 1-hydroxy-2-(imidazol-3-ium-1-yl)ethylidene-1,1-diphosphonato]-kappa(5)O:O,O':O',O''], [Ca(C(5)H(8)N(2)O(7)P(2))(H(2)O)](n), consists instead of a Ca(II) cation in a general position, a zwitterionic zoledronate(2-) anion and a coordinated water molecule. The geometry around the Ca(II) atom, provided by six bisphosphonate O atoms and one water ligand, is that of a pentagonal bipyramid with the Ca(II) atom displaced by 0.19 A out of the equatorial plane. These Ca(II) coordination polyhedra are ;threaded' by the 2(1) axis so that successive polyhedra share edges of their pentagonal basal planes. This results in a strongly coupled rhomboidal Ca(2)-O(2) chain which runs along [010]. These chains are in turn linked by an apical O atom from a -PO(3) group in a neighbouring chain. This O-atom, shared between chains, generates strong covalently bonded planar arrays parallel to (100). Finally, these sheets are linked by hydrogen bonds into a three-dimensional structure. Owing to the extreme affinity of zoledronic acid for bone tissue, in general, and with calcium as one of the major constituents of bone, it is expected that this structure will be useful in modelling some of the biologically interesting processes in which the drug takes part.

  16. Comparison of the one-electron oxidations of CO-bridged vs unbridged bimetallic complexes: Electron-transfer chemistry of Os2Cp2(CO)4 and Os2Cp∗2(μ-CO)2(CO)2 (Cp = η5-C5H5, Cp∗ = η5-C5Me5)

    KAUST Repository

    Laws, Derek R.

    2014-09-22

    The one-electron oxidations of two dimers of half-sandwich osmium carbonyl complexes have been examined by electrochemistry, spectro-electrochemistry, and computational methods. The all-terminal carbonyl complex Os2Cp2(CO)4 (1, Cp = η5-C5H5) undergoes a reversible one-electron anodic reaction at E1/2 = 0.41 V vs ferrocene in CH2Cl2/0.05 M [NBu4][B(C6F5)4], giving a rare example of a metal-metal bonded radical cation unsupported by bridging ligands. The IR spectrum of 1+ is consistent with an approximately 1:1 mixture of anti and gauche structures for the 33 e- radical cation in which it has retained all-terminal bonding of the CO ligands. Density functional theory (DFT) calculations, including orbital-occupancy-perturbed Mayer bond-order analyses, show that the highest-occupied molecular orbitals (HOMOs) of anti-1 and gauche-1 are metal-ligand delocalized. Removal of an electron from 1 has very little effect on the Os-Os bond order, accounting for the resistance of 1+ to heterolytic cleavage. The Os-Os bond distance is calculated to decrease by 0.10 å and 0.06 å as a consequence of one-electron oxidation of anti-1 and gauche-1, respectively. The CO-bridged complex Os2Cp∗2(μ-CO)2(CO)2 (Cp∗ = η5-C5Me5), trans-2, undergoes a more facile oxidation, E1/2 = -0.11 V, giving a persistent radical cation shown by solution IR analysis to preserve its bridged-carbonyl structure. However, ESR analysis of frozen solutions of 2+ is interpreted in terms of the presence of two isomers, most likely anti-2+ and trans-2+, at low temperature. Calculations show that the HOMO of trans-2 is highly delocalized over the metal-ligand framework, with the bridging carbonyls accounting for about half of the orbital makeup. The Os-Os bond order again changes very little with removal of an electron, and the Os-Os bond length actually undergoes minor shortening. Calculations suggest that the second isomer of 2+ has the anti all-terminal CO structure. (Figure Presented) © 2014 American

  17. Chelate-size effects on the structures, chemical behavior, properties, and catalytic activity of the new palladium(II)-allyl complexes [Pd(eta(3)-1-R-1-C3H4){FcCH=N-CH2-(CH2)(n)-NMe2}][PF6] {Fc = (eta(5)-C5H5)Fe(eta(5)-C5H4), n=2 or 1, and R-1 = h or ph}

    NARCIS (Netherlands)

    Pérez, S.; López, C.; Bosque, R.; Solans, X.; Font-Bardía, M.; Roig, A.; Molins, E.; van Leeuwen, P.W.N.M.; van Strijdonck, G.P.F.; Freixa, Z.

    2008-01-01

    The synthesis, X-ray crystal structures, and the study of the solution behavior of the palladium(II) allyl complexes [Pd(eta(3)-1R(1)-C3H4){FcCH=N-CH2-(CH2)(n)-NMe2}][PF6] {with Fc = (eta(5)-C5H5)Fe(eta(5)-C5H4), R-1 = H, and n = 2 (4) or 1 (5) or R-1 = Ph and n = 2 (6) or 1 (7)} are described. The

  18. Overexpression of PP2A-C5 that encodes the catalytic subunit 5 of protein phosphatase 2A in Arabidopsis confers better root and shoot development under salt conditions

    Science.gov (United States)

    Protein phosphatase 2A (PP2A) is an enzyme consisting of three subunits: a scaffolding A subunit, a regulatory B subunit and a catalytic C subunit. PP2As were shown to play diverse roles in eukaryotes. In this study, the function of the Arabidopsis PP2A-C5 gene that encodes the catalytic subunit 5 o...

  19. Synthesis and chemistry of the open-cage cobaltaheteroborane cluster [{(η(5)-C5Me5)Co}2B2H2Se2]: a combined experimental and theoretical study.

    Science.gov (United States)

    Barik, Subrat Kumar; Dorcet, Vincent; Roisnel, Thierry; Halet, Jean-François; Ghosh, Sundargopal

    2015-08-28

    Reaction of [(η(5)-C5Me5)CoCl]2 with a two-fold excess of [LiBH4·thf] followed by heating with an excess of Se powder produces the dicobaltaselenaborane species [{(η(5)-C5Me5)Co}2B2H2Se2], , in good yield. The geometry of resembles a nido pentagonal [Co2B2Se2] bipyramid with a missing equatorial vertex. It can alternatively be seen as an open cage triple-decker cluster. Isolation of permits its reaction with [Fe2(CO)9] to give heterometallic diselenametallaborane [{(η(5)-C5Me5)Co}Fe(CO)3B2H2Se2], . The geometry of is similar to that of with one of the [(η(5)-C5Me5)Co] groups replaced by the isolobal, two-electron fragment [Fe(CO)3]. Both new compounds have been characterized by mass spectrometry, and by (1)H, (11)B and (13)C NMR spectroscopy. The structural architectures have been unequivocally established by crystallographic analysis. In addition, density functional theory calculations were performed to investigate the bonding and electronic properties. The large HOMO-LUMO gaps computed for both clusters are consistent with their thermodynamic stability. Natural bond order calculations predict the absence of metal-metal bonding interaction.

  20. Design of music player based on MCU STC12C5A60S2%一种基于51单片机的音乐播放器的设计

    Institute of Scientific and Technical Information of China (English)

    何谐; 唐大权; 张淑廷; 陈雪

    2014-01-01

    The hardware design method of the music player based on MCU STC12C5A60S2 is introduced in this paper. The program design of the music player based on principle of FAT32 file system is studied. In the music player, MCU STC12C5A60S2 is taken as a main controller,SD card as a memory medium of music files and VS1003 chip as a decoder unit. When the player is running,MCU STC12C5A60S2 reads the music file from the SD card and continuously transfers data flow to VS1003 for decoding. In the meantime,the OLED liquid crystal display shows the message of the music in real time. The tested results from experiments show the music player can play the music files in multiple formats fluently if the player is connected with ear phone.%主要介绍一种基于51单片机的音乐播放器的硬件设计方法,并研究在FAT32文件系统下音乐播放器的程序设计。该音乐播放器采用STC12C5A60S2单片机为主控制器,SD卡作为音乐文件的存储介质,VS1003芯片作为解码器。STC12C5A60S2单片机从 SD卡中读取音乐文件,并不断将数据流传送至VS1003解码,最后连接耳机播放,同时STC12C5A60S2连接OLED液晶显示屏实时显示音乐播放信息。实验表明,该音乐播放器连接耳机能流畅播放多种格式的音乐文件。

  1. Calculations of total electron-impact ionization cross sections for Fluoroketone C5F10O and Fluoronitrile C4F7N using modified Deutsch-Märk formula

    Science.gov (United States)

    Xiong, Jiayu; Li, Xingwen; Wu, Jian; Guo, Xiaoxue; Zhao, Hu

    2017-11-01

    Both fluoroketone C5F10O and fluoronitrile C4F7N are promising substitute gases for SF6. The electron-impact ionization cross sections for these two gases are calculated using the Deutsch-Märk (DM) formula and its modified method. The necessary molecular geometry optimization and electron population were determined by ab initio calculation, which was performed with quantum chemistry code. The level of calculation, including the theoretical method and basis-set, are carefully determined. To eliminate the drawbacks of the DM formula, a modified DM formula is set in this paper. The modified DM formula, of which the weighting factors are changed, has a better agreement with the experimental data on both the peak and shape of the cross-section curves. The results calculated by DM formula and modified DM formula are given as references to fill in gaps in further research into C5F10O and C4F7N.

  2. Technology Insertion-Engineering Services Process Characterization. Task Order No. 1. Book 2 of 5. Database Documentation Book. OO-ALC MANPRA (C5 Main Landing Gear - WCD’S)

    Science.gov (United States)

    1989-12-15

    ORDER NO. 1 BOOK 2 OF 5 DATABASE DOCUMENTATION BOOK 00-ALC MANPRA *(C5 MAIN LANDING GEAR- WCD’S) CONTRACT SUMMARY REPORT , 15 DECEMBER 1989 ’.1 - CONTRACT...ORIQ 1 . T A 1~4 M E* X C I" El 1 -:11 E:XCE:EI:IIE:U RE:CORI’ RFiS CvAUiS FOREXE IN REWORK LI[MITS Ill FINAL DESTINATION 22. COOROINATION/INITIATING MCC

  3. Tailoring of the structure of Pt/WO3–ZrO2 catalyst for high activity in skeletal isomerization of C5–C6 paraffins under industrially relevant conditions

    Czech Academy of Sciences Publication Activity Database

    Hidalgo, J. M.; Kaucký, Dalibor; Bortnovsky, O.; Sobalík, Zdeněk; Černý, R.

    2015-01-01

    Roč. 41, č. 12 (2015), s. 9425-9437 ISSN 0922-6168 R&D Projects: GA MPO FR-TI3/316 Institutional support: RVO:61388955 Keywords : Pt/WOx–ZrO2 catalyst * Isomerization of C5–C6 paraffins * Heteroatom-substituted zirconia Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.833, year: 2015

  4. Ab initio/GIAO-CCSD(T) study of structures, energies, and 13C NMR chemical shifts of C4H7(+) and C5H9(+) ions: relative stability and dynamic aspects of the cyclopropylcarbinyl vs bicyclobutonium ions.

    Science.gov (United States)

    Olah, George A; Surya Prakash, G K; Rasul, Golam

    2008-07-16

    The structures and energies of the carbocations C 4H 7 (+) and C 5H 9 (+) were calculated using the ab initio method. The (13)C NMR chemical shifts of the carbocations were calculated using the GIAO-CCSD(T) method. The pisigma-delocalized bisected cyclopropylcarbinyl cation, 1 and nonclassical bicyclobutonium ion, 2 were found to be the minima for C 4H 7 (+) at the MP2/cc-pVTZ level. At the MP4(SDTQ)/cc-pVTZ//MP2/cc-pVTZ + ZPE level the structure 2 is 0.4 kcal/mol more stable than the structure 1. The (13)C NMR chemical shifts of 1 and 2 were calculated by the GIAO-CCSD(T) method. Based on relative energies and (13)C NMR chemical shift calculations, an equilibrium involving the 1 and 2 in superacid solutions is most likely responsible for the experimentally observed (13)C NMR chemical shifts, with the latter as the predominant equilibrating species. The alpha-methylcyclopropylcarbinyl cation, 4, and nonclassical bicyclobutonium ion, 5, were found to be the minima for C 5H 9 (+) at the MP2/cc-pVTZ level. At the MP4(SDTQ)/cc-pVTZ//MP2/cc-pVTZ + ZPE level ion 5 is 5.9 kcal/mol more stable than the structure 4. The calculated (13)C NMR chemical shifts of 5 agree rather well with the experimental values of C 5H 9 (+).

  5. The methyltransferase NSD3 has chromatin-binding motifs, PHD5-C5HCH, that are distinct from other NSD (nuclear receptor SET domain) family members in their histone H3 recognition.

    Science.gov (United States)

    He, Chao; Li, Fudong; Zhang, Jiahai; Wu, Jihui; Shi, Yunyu

    2013-02-15

    The NSD (nuclear receptor SET domain-containing) family members, consisting of NSD1, NSD2 (MMSET/WHSC1), and NSD3 (WHSC1L1), are SET domain-containing methyltransferases and aberrant expression of each member has been implicated in multiple diseases. They have specific mono- and dimethylase activities for H3K36, whereas play nonredundant roles during development. Aside from the well characterized catalytic SET domain, NSD proteins have multiple potential chromatin-binding motifs that are clinically relevant, including the fifth plant homeodomain (PHD5) and the adjacent Cys-His-rich domain (C5HCH) located at the C terminus. Herein, we report the crystal structures of the PHD5-C5HCH module of NSD3, in the free state and in complex with H3(1-7) (H3 residues 1-7), H3(1-15) (H3 residues 1-15), and H3(1-15)K9me3 (H3 residues 1-15 with trimethylation on K9) peptides. These structures reveal that the PHD5 and C5HCH domains fold into a novel integrated PHD-PHD-like structural module with H3 peptide bound only on the surface of PHD5 and provide the molecular basis for the recognition of unmodified H3K4 and trimethylated H3K9 by NSD3 PHD5. Structural studies and binding assays show that differences exist in histone binding specificity of the PHD5 domain between three members of the NSD family. For NSD2, the PHD5-C5HCH:H3 N terminus interaction is largely conserved, although with a stronger preference for unmethylated H3K9 (H3K9me0) than trimethylated H3K9 (H3K9me3), and NSD1 PHD5-C5HCH does not bind to H3 peptides. Our results shed light on how NSD proteins that mediate H3K36 methylation are localized to specific genomic sites and provide implications for the mechanism of functional diversity of NSD proteins.

  6. Synthesis of phenobarbital 14C - 5 (1964)

    International Nuclear Information System (INIS)

    Benakis, A.

    1964-01-01

    Phenobarbital (Luminal), well known as a hypnotic agent, plays also an important role in the medical treatment of epilepsy. With the object of studying the metabolism of this medicament in the living system, the synthesis of phenobarbital marked in position 2 of the pyrimidinic ring has been effected. It has been necessary, in order to carry out to research into the metabolism of this product, to have a phenobarbital marked in position 5 of the pyrimidinic ring. This synthesis, making it possible to introduce C-14 into position 5 of the pyrimidinic ring, consists of seven stages starting from C-14 carboxyl benzoic acid having a specific activity of 25 mc/mM. The melting point of the final product is 172 - 173 deg. C and its specific activity is 11.15 mc/mM. The overall radioactive yield of the pure product, with respect to the original benzoic acid (10 mM) is of the order of 3 per cent. The purity of the product has been controlled by paper chromatography; it is of the order of 99 per cent. (author) [fr

  7. C-5 Confined Space Technical Guidance Document

    National Research Council Canada - National Science Library

    Kapranos, Sophia

    2002-01-01

    ...) strict Technical Order (TO) and Operating Instruction (0I) directives. The TOs and OIs govern procedures such as lockout/tagout and system checks prior to entering the various areas of an aircraft.

  8. Study on in vivo examination of tumors of epithelial origin for the monoclonales antibodies ior c5, ior egf/r3 and humanized hr3, by using inmunogammagraphy technique

    International Nuclear Information System (INIS)

    Ramos Suzarte, Mayra; Iznaga Escobar, Normando; Torres Gemil, Olga; Rodriguez Obaya, Teresita; Perez Rodriguez, Rolando; Rodriguez Mesa, Nelson; Oliva Gonzalez, Juan P.; Perera Pintado, Alejandro; Torres Aroche, Leonel; Batista Cuellar, Juan; Gonzalez Lazo, Nery; Cruz, Teresa; Leonard, Ibrahim; Neninger, Elia

    2003-01-01

    The present work is aimed at demonstrating that humanized hR3 and ior egf/r3, ior c5, ior cea-1 murine monoclonal antibodies (mAbs) can identify primary neoplasia lesions, Their post-surgical received and metastasis by using immunography, Results showed that above mentioned mAbs are useful for the diagnosis of epithelial tumors, their metastasis and post-surgical received. this technique becomes a concept prove for further use of mAbs in cancer therapy

  9. Case report 332: A complex anomaly of the craniovertebral junction representing a regressive malformation with agenesis of the neural arch of C-2, hypomorphogenesis at C5-C6 and instability of the upper cervical spine

    International Nuclear Information System (INIS)

    Bernini, F.P.; Muras, I.

    1985-01-01

    In summary, a very complex anomaly, including agenesis of the neural arch of the axis, hypomorphogenesis of the cervical spine at the C5-C6 level with a partial ''blocked'' vertebra and disability of the upper cervical spine, is reported in a 31-year-old man. The anomalies associated with these changes are described in detail in the text and illustrated radiologically. The relationship of the embryological alterations in contrast with the normal is described and emphasized, particularly in the upper cervical area. It is stressed that narrowing of the space from the back of the odontoid (or the posterior lip of the foramen magnum) is a direct result of the complex anomalies described in this case, producing compression of the medulla and/or the upper cervical spinal cord. The literature on this subject is reviewed in depth. (orig.)

  10. Postvaccination C-Reactive Protein and C5/gp41732-744 Antibody Level Fold-Changes Over Baseline Are Independent Predictors of Therapeutic HIV Vaccine Effect in a Phase 2 Clinical Study of Vacc-4x.

    Science.gov (United States)

    Huang, Yunda; Zhang, Lily; Jolliffe, Darren; Sanchez, Brittany; Stjernholm, Grete; Jelmert, Øyvind; Ökvist, Mats; Sommerfelt, Maja A

    2018-03-01

    Therapeutic vaccination has the potential to contribute to functional HIV cure strategies. However, to show functional HIV cure, study participants must be taken off combination antiretroviral therapy (cART). The availability of suitable biomarkers that can predict viral load (VL) or CD4 count outcomes following therapeutic HIV vaccination would reduce the risks associated with cART interruption in such studies. This report sought to determine baseline and postvaccination biomarker predictors of vaccine effect (VE) on VL and CD4 counts following cART interruption in a double-blind, randomized phase 2 study of the peptide-based therapeutic HIV vaccine, Vacc-4x (n = 93), versus placebo (n = 43). Antibody responses to a novel envelope glycoprotein antigen, C5/gp41 732-744 , and three safety marker measurements [C-reactive protein (CRP), white blood cell, and lactate dehydrogenase] were considered. Interaction tests in univariate and multivariate linear regression models were used to estimate the effect of biomarkers on VE, defined as the VL or CD4 count difference in Vacc-4x versus placebo groups. The reported q-values (considered significant for hypothesis-generating purposes if ≤0.2) accounted for multiple comparisons using the false discovery rate method. Data were analyzed from all available 58 Vacc-4x and 25 placebo recipients before cART resumption. Lower postvaccination fold-change over baseline of CRP concentration (interaction p- (q-) value = 0.005 (0.11) for VL) and higher fold-change of anti-C5/gp41 732-744 antibody levels (0.005 (0.11) for VL and 0.009 (0.20) for CD4) were associated with Vacc-4x benefit. These findings suggest potential roles for inflammation and immune activation markers in predicting therapeutic HIV VE.

  11. Structure and thermodynamic properties of (C5H12N)CuBr3: a new weakly coupled antiferromagnetic spin-1/2 chain complex lying in the 1D-3D dimensional cross-over regime.

    Science.gov (United States)

    Pan, Bingying; Wang, Yang; Zhang, Lijuan; Li, Shiyan

    2014-04-07

    Single crystals of a metal organic complex (C5H12N)CuBr3 (C5H12N = piperidinium, pipH for short) have been synthesized, and the structure was determined by single-crystal X-ray diffraction. (pipH)CuBr3 crystallizes in the monoclinic group C2/c. Edging-sharing CuBr5 units link to form zigzag chains along the c axis, and the neighboring Cu(II) ions with spin-1/2 are bridged by bibromide ions. Magnetic susceptibility data down to 1.8 K can be well fitted by the Bonner-Fisher formula for the antiferromagnetic spin-1/2 chain, giving the intrachain magnetic coupling constant J ≈ -17 K. At zero field, (pipH)CuBr3 shows three-dimensional (3D) order below TN = 1.68 K. Calculated by the mean-field theory, the interchain coupling constant J' = -0.91 K is obtained and the ordered magnetic moment m0 is about 0.23 μB. This value of m0 makes (pipH)CuBr3 a rare compound suitable to study the 1D-3D dimensional cross-over problem in magnetism, since both 3D order and one-dimensional (1D) quantum fluctuations are prominent. In addition, specific heat measurements reveal two successive magnetic transitions with lowering temperature when external field μ0H ≥ 3 T is applied along the a' axis. The μ0H-T phase diagram of (pipH)CuBr3 is roughly constructed.

  12. Synthesis and reactivity of bis(tetramethylcyclopentadienyl) yttrium metallocenes including the reduction of Me(3)SiN(3) to [(Me(3)Si)(2)N](-) with [(C(5)Me(4)H)(2)Y(THF)](2)(mu-eta(2):eta(2)-N(2)).

    Science.gov (United States)

    Lorenz, Sara E; Schmiege, Benjamin M; Lee, David S; Ziller, Joseph W; Evans, William J

    2010-07-19

    The metallocene precursors needed to provide the tetramethylcyclopentadienyl yttrium complexes (C(5)Me(4)H)(3)Y, [(C(5)Me(4)H)(2)Y(THF)](2)(mu-eta(2):eta(2)-N(2)), and [(C(5)Me(4)H)(2)Y(mu-H)](2) for reactivity studies have been synthesized and fully characterized, and their reaction chemistry has led to an unexpected conversion of an azide to an amide. (C(5)Me(4)H)(2)Y(mu-Cl)(2)K(THF)(x), 1, synthesized from YCl(3) and KC(5)Me(4)H reacts with allylmagnesium chloride to make (C(5)Me(4)H)(2)Y(eta(3)-C(3)H(5)), 2, which is converted to [(C(5)Me(4)H)(2)Y][(mu-Ph)(2)BPh(2)], 3, with [Et(3)NH][BPh(4)]. Complex 3 reacts with KC(5)Me(4)H to form (C(5)Me(4)H)(3)Y, 4. The reduced dinitrogen complex, [(C(5)Me(4)H)(2)Y(THF)](2)(mu-eta(2):eta(2)-N(2)), 5, can be synthesized from either [(C(5)Me(4)H)(2)Y](2)[(mu-Ph)(2)BPh(2)], 3, or (C(5)Me(4)H)(3)Y, 4, with potassium graphite under a dinitrogen atmosphere. The (15)N labeled analogue, [(C(5)Me(4)H)(2)Y(THF)](2)(mu-eta(2):eta(2)-(15)N(2)), 5-(15)N, has also been prepared, and the (15)N NMR data have been compared to previously characterized reduced dinitrogen complexes. Complex 2 reacts with H(2) to form the corresponding hydride, [(C(5)Me(4)H)(2)Y(mu-H)](2), 6. Complex 5 displays similar reactivity to that of the analogous [(C(5)Me(4)H)(2)Ln(THF)](2)(mu-eta(2):eta(2)-N(2)) complexes (Ln = La, Lu), with substrates such as phenazine, anthracene, and CO(2). In addition, 5 reduces Me(3)SiN(3) to form (C(5)Me(4)H)(2)Y[N(SiMe(3))(2)], 7.

  13. NMR and TRLFS studies of Ln(iii) and An(iii) C5-BPP complexes† †Electronic supplementary information (ESI) available: LIFDI-MS spectra and additional NMR spectra. See DOI: 10.1039/c4sc03103b

    Science.gov (United States)

    Beele, Björn B.; Geist, Andreas; Müllich, Udo; Kaden, Peter; Panak, Petra J.

    2015-01-01

    C5-BPP is a highly efficient N-donor ligand for the separation of trivalent actinides, An(iii), from trivalent lanthanides, Ln(iii). The molecular origin of the selectivity of C5-BPP and many other N-donor ligands of the BTP-type is still not entirely understood. We present here the first NMR studies on C5-BPP Ln(iii) and An(iii) complexes. C5-BPP is synthesized with 10% 15N labeling and characterized by NMR and LIFDI-MS methods. 15N NMR spectroscopy gives a detailed insight into the bonding of C5-BPP with lanthanides and Am(iii) as a representative for trivalent actinide cations, revealing significant differences in 15N chemical shift for coordinating nitrogen atoms compared to Ln(iii) complexes. The temperature dependence of NMR chemical shifts observed for the Am(iii) complex indicates a weak paramagnetism. This as well as the observed large chemical shift for coordinating nitrogen atoms show that metal–ligand bonding in Am(C5-BPP)3 has a larger share of covalence than in lanthanide complexes, confirming earlier studies. The Am(C5-BPP)3 NMR sample is furthermore spiked with Cm(iii) and characterized by time-resolved laser fluorescence spectroscopy (TRLFS), yielding important information on the speciation of trace amounts of minor complex species. PMID:29560242

  14. Synthesis of phenobarbital {sup 14}C - 5 (1964); Synthese du phenobarbital {sup 14}C - 5 (1964)

    Energy Technology Data Exchange (ETDEWEB)

    Benakis, A [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    Phenobarbital (Luminal), well known as a hypnotic agent, plays also an important role in the medical treatment of epilepsy. With the object of studying the metabolism of this medicament in the living system, the synthesis of phenobarbital marked in position 2 of the pyrimidinic ring has been effected. It has been necessary, in order to carry out to research into the metabolism of this product, to have a phenobarbital marked in position 5 of the pyrimidinic ring. This synthesis, making it possible to introduce C-14 into position 5 of the pyrimidinic ring, consists of seven stages starting from C-14 carboxyl benzoic acid having a specific activity of 25 mc/mM. The melting point of the final product is 172 - 173 deg. C and its specific activity is 11.15 mc/mM. The overall radioactive yield of the pure product, with respect to the original benzoic acid (10 mM) is of the order of 3 per cent. The purity of the product has been controlled by paper chromatography; it is of the order of 99 per cent. (author) [French] Le phenobarbital (Luminal) bien connu comme agent hypnotique, joue egalement un role important dans la medication anti-epileptique. Pour l'etude du metabolisme de ce medicament dans l'organisme vivant, nous avons synthetise le phenobarbital marque en position 2 du cycle pyrimidinique. Afin de poursuivre la recherche du metabolisme de ce produit, il a ete necessaire de disposer du phenobarbital marque en position 5 du cycle. pyrimidinique. Cette synthese, permettant l'introduction du {sup 14}C en position 5 du cycle pyrimidinique, comporte sept etapes, au depart de l'acide benzoique carboxyle {sup 14}C, d'une activite specifique de 25 mc/mM. Point de fusion du produit final: 172 - 173 deg. C Activite specifique: 11,15 mC/mM. Rendement total radioactif du produit pur, par rapport a l'acide benzoique de depart sur 10 mM, de l'ordre de 3 pour cent. La purete du produit a ete controlee par chromatographie sur papier; elle est de l'ordre de 99 pour cent. (auteur)

  15. Screening for the optimal induction parameters for periplasmic ...

    African Journals Online (AJOL)

    ONOS

    2010-09-20

    Sep 20, 2010 ... 3Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, ... induce protein expression can be varied to adjust the ..... disruption in high pressure homogenizer.

  16. Plasmin cleaves fibrinogen and the human complement proteins C3b and C5 in the presence of Leptospira interrogans proteins: A new role of LigA and LigB in invasion and complement immune evasion.

    Science.gov (United States)

    Castiblanco-Valencia, Mónica Marcela; Fraga, Tatiana Rodrigues; Pagotto, Ana Helena; Serrano, Solange Maria de Toledo; Abreu, Patricia Antonia Estima; Barbosa, Angela Silva; Isaac, Lourdes

    2016-05-01

    Plasminogen is a single-chain glycoprotein found in human plasma as the inactive precursor of plasmin. When converted to proteolytically active plasmin, plasmin(ogen) regulates both complement and coagulation cascades, thus representing an important target for pathogenic microorganisms. Leptospira interrogans binds plasminogen, which is converted to active plasmin. Leptospiral immunoglobulin-like (Lig) proteins are surface exposed molecules that interact with extracellular matrix components and complement regulators, including proteins of the FH family and C4BP. In this work, we demonstrate that these multifunctional molecules also bind plasminogen through both N- and C-terminal domains. These interactions are dependent on lysine residues and are affected by ionic strength. Competition assays suggest that plasminogen does not share binding sites with C4BP or FH on Lig proteins at physiological molar ratios. Plasminogen bound to Lig proteins is converted to proteolytic active plasmin in the presence of urokinase-type plasminogen activator (uPA). Lig-bound plasmin is able to cleave the physiological substrates fibrinogen and the complement proteins C3b and C5. Taken together, our data point to a new role of LigA and LigB in leptospiral invasion and complement immune evasion. Plasmin(ogen) acquisition by these versatile proteins may contribute to Leptospira infection, favoring bacterial survival and dissemination inside the host. Copyright © 2016. Published by Elsevier GmbH.

  17. Molecular and crystal structure of nido-9-C5H5N-11-I-7,8-C2B9H10: supramolecular architecture via hydrogen bonding X-H...I (X = B, C)

    International Nuclear Information System (INIS)

    Polyanskaya, T.M.

    2006-01-01

    A monocrystal X-ray diffraction study of a new iodine-containing cluster compound 9-(pyridine)-11-iodo-decahydro-7,8-dicarba-nido-undecaborane [9-C 5 H 5 N-11-I-7,8-C 2 B 9 H 10 ] has been performed. Crystal data: C 7 H 15 B 9 NI, M = 337.39, monoclinic, space group P2 1 /c, unit cell parameters: a=9.348(1) A, b=11.159(1) A, c=13.442(2) A, β=98.13(1) deg, V=1388.1(5) A 3 , Z=4, d calc = 1.614 g/cm 3 , T = 295 K, F(000)=648, μ=2.276 mm -1 . The structure was solved by a direct method and refined in the full-matrix anisotropic approximation (isotropic for hydrogen atoms) to final agreement factors R 1 = 0.0254, wR 2 = 0.0454 for 2437 I hkl >2σ I from 3590 measured I hkl (an Enraf-Nonius CAD-4 diffractometer, λMoK α , graphite monochromator, θ/2θ-scanning). The molecules are joined into a supramolecular assembly by hydrogen bonds X-H...I (X = B, C) [ru

  18. Association of miR-548c-5p, miR-7-5p, miR-210-3p, miR-128-3p with recurrence in systemically untreated breast cancer

    DEFF Research Database (Denmark)

    Block, Ines; Burton, Mark; Sørensen, Kristina Pilekær

    2018-01-01

    . To validate their prognostic potential, we analyzed microRNA expression in an independent cohort (n = 110) using a pairmatched study design minimizing dependence of classical markers. The expression of hsa-miR-548c-5p was significantly associated with abridged disease-free survival (hazard ratio [HR]:1.96, p...... = 0.027). Contradicting published results, high hsa-miR516-3p expression was associated with favorable outcome (HR:0.29, p = 0.0068). The association is probably time-dependent indicating later relapse. Additionally, re-analysis of previously published expression data of two matching cohorts (n = 100......, n = 255) supports an association of hsa-miR-128-3p with shortened diseasefree survival (HR:2.48, p = 0.0033) and an upregulation of miR-7-5p (p = 0.0038; p = 0.039) and miR-210-3p (p = 0.031) in primary tumors of patients who experienced metastases. Further analysis may verify the prognostic...

  19. Thermo-physical characterization of the Fe_6_7Mo_6Ni_3_._5Cr_3_._5P_1_2C_5_._5B_2_._5 bulk metallic glass forming alloy

    International Nuclear Information System (INIS)

    Bochtler, Benedikt; Gross, Oliver; Gallino, Isabella; Busch, Ralf

    2016-01-01

    The iron-phosphorus based bulk metallic glass forming alloy Fe_6_7Mo_6Ni_3_._5Cr_3_._5P_1_2C_5_._5B_2_._5 is characterized with respect to its thermophysical properties, crystallization and relaxation behavior, as well as its viscosity. The alloy provides a high critical casting thickness of 13 mm, thus allowing for the casting of amorphous parts with a considerable size. Calorimetric measurements reveal the characteristic transformation temperatures, transformation enthalpies, and the specific heat capacity. The analyses show that no stable supercooled liquid region exists upon heating. The specific heat capacity data are used to calculate the enthalpy, entropy, and Gibbs free energy differences between the crystalline and the supercooled liquid state. The crystallization behavior of amorphous samples upon heating is analyzed by differential scanning calorimetry and X-ray diffraction, and a time-temperature-transformation diagram is constructed. Dilatometry is used to determine the thermal expansion behavior. The equilibrium viscosity below the glass transition as well as volume relaxation behavior are measured by three-point beam bending and dilatometry, respectively, to assess the kinetic fragility. With a kinetic fragility parameter of D* = 21.3, the alloy displays a rather strong liquid behavior. Viscosity above the melting point is determined using electromagnetic levitation in microgravity on a reduced gravity aircraft in cooperation with the German Aerospace Center (DLR). These high-temperature viscosity data are compared with the low-temperature three-point beam bending measurements. The alloy displays a strong liquid behavior at low temperatures and a fragile behavior at high temperatures. These results are analogous to the ones observed in several Zr-based bulk metallic glass forming liquids, indicating a strong to fragile liquid-liquid transition in the undercooled liquid, which is obscured by crystallization.

  20. Theoretical Prediction on [5]Radialene Sandwich Complexes (CpM)2(C10H10) (Cp = η5-C5H5; M = Fe, Co, Ni): Geometry, Spin States, and Bonding.

    Science.gov (United States)

    Liu, Nan-Nan; Xue, Ying-Ying; Ding, Yi-Hong

    2017-02-09

    [5]Radialene, the missing link for synthesis of radialene family, has been finally obtained via the preparation and decomplexation of the [5]radialene-bis-Fe(CO) 3 complex. The stability of [5]radialene complex benefits from the coordination with Fe(CO) 3 by losing free 1,3-butadiene structures to avoid polymerization. In light of the similar coordination ability of half-sandwiches CpM(Cp = η 5 -C 5 H 5 ; M = Fe, Co, Ni), there is a great possibility that the sandwiched complexes of [5]radialene with CpM are available. Herein, we present the first theoretical prediction on the geometry, spin states and bonding of (CpM)(C 10 H 10 ) and (CpM) 2 (C 10 H 10 ). For M = Fe, Co, Ni, the ground states of (CpM)(C 10 H 10 ) and (CpM) 2 (C 10 H 10 ) are doublet and triplet, singlet and singlet, and doublet and triplet states, where each Fe, Co, and Ni adopts 17, 18, and 19 electron-configuration, respectively. In particular, (CpFe) 2 (C 10 H 10 ) and (CpNi) 2 (C 10 H 10 ) have considerable open-shell singlet features. Generally the trans isomers of (CpM) 2 (C 10 H 10 ) with two CpM fragments on the opposite sides of the [5]radialene plane are apparently more stable than the cis ones with CpM fragments on the same side. However, for the singlet and triplet isomers of (CpNi) 2 (C 10 H 10 ) (both cis and trans isomers), the energy differences are relatively small, indicating that these isomers all have the opportunity to exist. Besides, the easy Diels-Alder (DA) dimerization between the [3]dendralene-like fragments of (CpM)(C 10 H 10 ) suggests the great difficulty in isolating the (CpM)(C 10 H 10 ) monomer.

  1. Molecular structures and excited states of CpM(CO)(2) (Cp = eta(5)-C(5)H(5); M = Rh, Ir) and [Cl(2)Rh(CO)(2)](-). Theoretical evidence for a competitive charge transfer mechanism.

    Science.gov (United States)

    Hu, Zhenming; Boyd, Russell J; Nakatsuji, Hiroshi

    2002-03-20

    Molecular structures and excited states of CpM(CO)(2) (Cp = eta(5)-C(5)H(5); M = Rh, Ir) and [Cl(2)Rh(CO)(2)](-) complexes have been investigated using the B3LYP and the symmetry-adapted cluster (SAC)/SAC-configuration interaction (SAC-CI) theoretical methods. All the dicarbonyl complexes have singlet ground electronic states with large singlet-triplet separations. Thermal dissociations of CO from the parent dicarbonyls are energetically unfavorable. CO thermal dissociation is an activation process for [Cl(2)Rh(CO)(2)](-) while it is a repulsive potential for CpM(CO)(2). The natures of the main excited states of CpM(CO)(2) and [Cl(2)Rh(CO)(2)](-) are found to be quite different. For [Cl(2)Rh(CO)(2)](-), all the strong transitions are identified to be metal to ligand CO charge transfer (MLCT) excitations. A significant feature of the excited states of CpM(CO)(2) is that both MLCT excitation and a ligand Cp to metal and CO charge transfer excitation are strongly mixed in the higher energy states with the latter having the largest oscillator strength. A competitive charge transfer excited state has therefore been identified theoretically for CpRh(CO)(2) and CpIr(CO)(2). The wavelength dependence of the quantum efficiencies for the photoreactions of CpM(CO)(2) reported by Lees et al. can be explained by the existence of two different types of excited states. The origin of the low quantum efficiencies for the C-H/S-H bond activations of CpM(CO)(2) can be attributed to the smaller proportion of the MLCT excitation in the higher energy states.

  2. Synthesis and pharmacological characterization of a new PET ligand for the serotonin transporter: [{sup 11}C]5-bromo-2-[2-(dimethylaminomethylphenylsulfanyl)]phenylamine ([{sup 11}C]DAPA)

    Energy Technology Data Exchange (ETDEWEB)

    Huang Yiyun E-mail: hh285@columbia.edu; Hwang, D.-R.; Zhu Zhihong; Bae, S.-A.; Guo Ningning; Sudo, Yasuhiko; Kegeles, Lawrence S.; Laruelle, Marc

    2002-10-01

    A new PET radioligand for the serotonin transporter (SERT), [{sup 11}C]-5-bromo-2-[2-(dimethylaminomethylphenylsulfanyl)]phenylamine ([{sup 11}C]DAPA (10), was synthesized and evaluated in vivo in rats and baboons. [{sup 11}C]DAPA (10) was prepared from its monomethylamino precursor 8 by reaction with high specific activity [{sup 11}C]methyl iodide. Radiochemical yield was 24{+-}5% based on [{sup 11}C]methyl iodide at end of bombardment (EOB, n=10) and specific activity was 1553{+-}939 Ci/mmol at end of synthesis (EOS, n=10). Binding assays indicated that [{sup 11}C]DAPA displays high affinity (Ki 1.49{+-}0.28 nM for hSERT) and good selectivity for the SERT in vitro. Biodistribution studies in rats indicated that [{sup 11}C]DAPA enters into the brain readily and localizes in brain regions known to contain high concentrations of SERT, such as the thalamus, hypothalamus, frontal cortex and striatum. Moreover, such binding in SERT-rich regions of the brain are blocked by pretreatment with either the selective serotonin reuptake inhibitor (SSRI) citalopram and by the cold compound itself, demonstrating that [{sup 11}C]DAPA binding in the rat brain is saturable and specific to SERT. Imaging experiments in baboons indicated that [{sup 11}C]DAPA binding is consistent with the known distribution of SERT in the baboon brain, with highest levels of radioactivity detected in the midbrain and thalamus, intermediate levels in the hippocampus and striatum, and lower levels in the cortical regions. Pretreatment of the baboon with citalopram 10 min before radioactivity injection blocked the binding of [{sup 11}C]DAPA in all brain regions that contain SERT. Kinetic analysis revealed that, in all brain regions examined, [{sup 11}C]DAPA specific to nonspecific distribution volume ratios (V{sub 3}'') are higher than [{sup 11}C](+)-McN 5652 and similar to [{sup 11}C]DASB. In summary, [{sup 11}C]DAPA appears to be a promising radioligand suitable for the visualization of SERT

  3. Dual Functions of the C5a Receptor as a Connector for the K562 Erythroblast-Like Cell-THP-1 Macrophage-Like Cell Island and as a Sensor for the Differentiation of the K562 Erythroblast-Like Cell during Haemin-Induced Erythropoiesis

    Directory of Open Access Journals (Sweden)

    Hiroshi Nishiura

    2012-01-01

    Full Text Available The transcriptional nuclear factor binding to the Y box of human leukocyte antigen genes (NF-Y for the C5a receptor (C5aR gene is active in erythroblasts. However, the roles of the C5aR in erythropoiesis are unclear. We have previously demonstrated that apoptotic cell-derived ribosomal protein S19 (RP S19 oligomers exhibit extraribosomal functions in promoting monocyte chemotaxis and proapoptosis via the C5aR without receptor internalisation. In contrast to the extraribosomal functions of the RP S19, a proapoptotic signal in pro-EBs, which is caused by mutations in the RP S19 gene, is associated with the inherited erythroblastopenia, Diamond-Blackfan anaemia. In this study, we detected C5aR expression and RP S19 oligomer generation in human erythroleukemia K562 cells during haemin-induced erythropoiesis. Under monocell culture conditions, the differentiation into K562 erythrocyte-like cells was enhanced following the overexpression of Wild-type RP S19. Conversely, the differentiation was repressed following the overexpression of mutant RP S19. An RP S19 oligomer inhibitor and a C5aR inhibitor blocked the association of the K562 basophilic EB-like cells and the THP-1 macrophage-like cells under coculture conditions. When bound to RP S19 oligomers, the C5aR may exhibit dual functions as a connector for the EB-macrophage island and as a sensor for EB differentiation in the bone marrow.

  4. SYNTHESIS AND STRUCTURAL FEATURES OF NOVEL VANADIUM(II) AMIDES - X-RAY STRUCTURES OF OCTAHEDRAL [(2-C5H4N)(CH3)N]2V(TMEDA) (TMEDA=N,N,N',N'-TETRAMETHYLETHYLENEDIAMINE) AND SQUARE-PYRAMIDAL [2,5-(CH3)2C4H2N]2V(PY)3 (PY=PYRIDINE)

    NARCIS (Netherlands)

    EDEMA, JJH; GAMBAROTTA, S; MEETSMA, A; SPEK, AL; VELDMAN, N

    1991-01-01

    The reaction of trans-(TMEDA)2VCl2 (TMEDA = N,N,N',N'-tetramethylethylenediamine) with both mono- and bidentate alkali-metal amides has been investigated. Utilization of 2 equiv of bidentate amide (N segment N)-M [M = Li, Na; N segment N = 2-?? (MeN)C5H4N (1), PhNNNPh (2), 7-azaindolyl (3),

  5. C-5M Fuel Efficiency Through MFOQA Data Analysis

    Science.gov (United States)

    2015-03-26

    then contribute to more accurate fuel loading and more efficient fleet fuel usage. Flight Operations Quality Assurance (FOQA) data uses the quick access ...into the ranges in Table 2. Visual Basic ( VBA ) code was written to quickly parse an entire mission (one of the thirty samples) into usable cruise...segments within the Altitude ranges of Table 2. The logic for focusing upon stable cruise flight segments was outlined in Chapter II. The VBA code

  6. C-5 Channel Delays: Analysis of Potential Causal Factors

    Science.gov (United States)

    2011-06-01

    generalized for use when considering variables other than those used during this research. Additionally, modification of the inputs to this tool with a...from maintenance problems. Pressurization and hydraulic system malfunctions were commonplace, and the complexity of the caster -capable landing gear...Charleston AFB, “one tire blew out upon the impact and another wheel departed from the landing gear completely, bouncing down the runway by itself

  7. Case report 449: Chondroblastoma involving C5 and C6

    Energy Technology Data Exchange (ETDEWEB)

    Howe, J.W.; Yochum, T.R.; Sladich, M.A.; Baumgard, S.

    1988-01-01

    A case of chondroblastoma of the cervical spine is presented in a sixteen year old male. Both the axial location and the presence of an associated soft tissue mass make this an unusual case. Treatment is briefly considered. (orig.)

  8. 26 CFR 1.663(c)-5 - Examples.

    Science.gov (United States)

    2010-04-01

    ... estate's income and does not participate in appreciation or depreciation in estate assets. During the... does not participate in appreciation or depreciation of the estate's assets. However, under the statute... fractional formula residuary bequests, the income and any appreciation in the value of the estate assets are...

  9. 26 CFR 301.6231(c)-5 - Criminal investigations.

    Science.gov (United States)

    2010-04-01

    ... criminal investigation for violation of the internal revenue laws relating to income tax will interfere... latest taxable year of the partner to which the criminal investigation relates shall be treated as... criminal investigation and written notification is sent by the Internal Revenue Service that the partner's...

  10. Does dinitrogen hydrogenation follow different mechanisms for [(eta5-C5Me4H)2Zr]2(mu2,eta2,eta2-N2) and {[PhP(CH2SiMe2NSiMe2CH2)PPh]Zr}2(mu2,eta2,eta2-N2) complexes? A computational study.

    Science.gov (United States)

    Bobadova-Parvanova, Petia; Wang, Qingfang; Quinonero-Santiago, David; Morokuma, Keiji; Musaev, Djamaladdin G

    2006-09-06

    The mechanisms of dinitrogen hydrogenation by two different complexes--[(eta(5)-C(5)Me(4)H)(2)Zr](2)(mu(2),eta(2),eta(2)-N(2)), synthesized by Chirik and co-workers [Nature 2004, 427, 527], and {[P(2)N(2)]Zr}(2)(mu(2),eta(2),eta(2)-N(2)), where P(2)N(2) = PhP(CH(2)SiMe(2)NSiMe(2)CH(2))(2)PPh, synthesized by Fryzuk and co-workers [Science 1997, 275, 1445]--are compared with density functional theory calculations. The former complex is experimentally known to be capable of adding more than one H(2) molecule to the side-on coordinated N(2) molecule, while the latter does not add more than one H(2). We have shown that the observed difference in the reactivity of these dizirconium complexes is caused by the fact that the former ligand environment is more rigid than the latter. As a result, the addition of the first H(2) molecule leads to two different products: a non-H-bridged intermediate for the Chirik-type complex and a H-bridged intermediate for the Fryzuk-type complex. The non-H-bridged intermediate requires a smaller energy barrier for the second H(2) addition than the H-bridged intermediate. We have also examined the effect of different numbers of methyl substituents in [(eta(5)-C(5)Me(n)H(5)(-)(n))(2)Zr](2)(mu(2),eta(2),eta(2)-N(2)) for n = 0, 4, and 5 (n = 5 is hypothetical) and [(eta(5)-C(5)H(2)-1,2,4-Me(3))(eta(5)-C(5)Me(5))(2)Zr](2)(mu(2),eta(2),eta(2)-N(2)) and have shown that all complexes of this type would follow a similar H(2) addition mechanism. We have also performed an extensive analysis on the factors (side-on coordination of N(2) to two Zr centers, availability of the frontier orbitals with appropriate symmetry, and inflexibility of the catalyst ligand environment) that are required for successful hydrogenation of the coordinated dinitrogen.

  11. Assembly of bicyclic or monocyclic clusters from [(η5-C5Me5)2Mo2(μ3-S)4(CuMeCN)2]2+ with tetraphosphine or N,P mixed ligands: syntheses, structures and enhanced third-order NLO performances.

    Science.gov (United States)

    Ren, Zhi-Gang; Sun, Sha; Dai, Min; Wang, Hui-Fang; Lü, Chun-Ning; Lang, Jian-Ping; Sun, Zhen-Rong

    2011-09-07

    Reactions of the preformed cluster [(η(5)-C(5)Me(5))(2)Mo(2)(μ(3)-S)(4)Cu(2)(MeCN)(2)](ClO(4))(2) (1) with two tetraphosphine ligands, 1,4-N,N,N',N'-tetra(diphenylphosphanylmethyl)benzene diamine (dpppda) and N,N,N',N'-tetra(diphenylphosphanylmethyl)ethylene diamine (dppeda), produced two bicyclic clusters {[(η(5)-C(5)Me(5))(2)Mo(2)(μ(3)-S)(4)Cu(2)](2)(L)}(ClO(4))(4) (3: L = dpppda; 4: L = dppeda). Analogous reactions of 1 or [(η(5)-C(5)Me(5))(2)Mo(2)(μ(3)-S)(4)Cu(2)(MeCN)(2)](PF(6))(2) (2) with two N,P mixed ligands, N,N-bi(diphenylphosphanylmethyl)-2-aminopyridine (bdppmapy) and N-diphenylphosphanylmethyl-4-aminopyridine (dppmapy), afforded two monocyclic clusters {[(η(5)-C(5)Me(5))(2)Mo(2)(μ(3)-S)(4)Cu(2)](2)(L)(2)}X(4) (5: L = bdppmapy, X = ClO(4); 6: L = dppmapy, X = PF(6)). Compounds 3-6 were fully characterized by elemental analysis, IR spectra, UV-vis spectra, (1)H and (31)P{(1)H} NMR spectra, ESI-MS and single-crystal X-ray crystallography. In the tetracations of 3-6, two cubane-like [Mo(2)(μ(3)-S)(4)Cu(2)] cores are linked either by one dpppda or dppeda bridge to form a bicyclic structure or by a pair of bdppmapy or dppmapy bridges to afford a monocyclic structure. The third-order nonlinear optical (NLO) properties of 1 and 3-6 in MeCN were also investigated by femtosecond degenerate four-wave mixing (DFWM) technique with a 50 fs pulse width at 800 nm. Compounds 3-6 exhibited enhanced third-order NLO performances relative to that of 1. This journal is © The Royal Society of Chemistry 2011

  12. Volume properties and refraction of aqueous solutions of bisadducts of light fullerene C60 and essential amino acids lysine, threonine, and oxyproline (C60(C6H13N2O2)2, C60(C4H8NO3)2, and C60(C5H9NO2)2) at 25°C

    Science.gov (United States)

    Semenov, K. N.; Ivanova, N. M.; Charykov, N. A.; Keskinov, V. A.; Kalacheva, S. S.; Duryagina, N. N.; Garamova, P. V.; Kulenova, N. A.; Nabieva, A.

    2017-02-01

    Concentration dependences of the density of aqueous solutions of bisadducts of light fullerene C60 and essential amino acids are studied by pycnometry. Concentration dependences of the average molar volumes and partial volumes of components (H2O and corresponding bisadducts) are calculated for C60(C6H13N2O2)2-H2O, C60(C4H8NO3)2-H2O, and C60(C5H9NO2)2-H2O binary systems at 25°C. Concentration dependences of the indices of refraction of C60(C6H13N2O2)2-H2O, C60(C4H8NO3)2-H2O, and C60(C5H9NO2)2-H2O binary systems are determined at 25°C. The concentration dependences of specific refraction and molar refraction of bisadducts and aqueous solutions of them are calculated.

  13. Quantitative evaluation of the biosynthetic pathways leading to δ-aminolevulinic acid from the Shemin precursor glycine via the C5 pathway in Arthrobacter hyalinus by analysis of 13C-labeled coproporphyrinogen III biosynthesized from [2-13C]glycine, [1-13C]acetate, and [2-13C]acetate using 13C NMR spectroscopy

    International Nuclear Information System (INIS)

    Katsumi Iida

    2013-01-01

    The biosynthetic pathways leading to δ-aminolevulinic acid (ALA) from the Shemin precursor glycine via the C5 pathway in Arthrobacter hyalinus were quantitatively evaluated by means of feeding experiments with [2- 13 C]glycine, sodium [1- 13 C]acetate, and sodium [2- 13 C]acetate, followed by analysis of the labeling patterns of coproporphyrinogen III (Copro'gen III) (biosynthesized from ALA) using 13 C NMR spectroscopy. Two biosynthetic pathways leading to ALA from glycine via the C5 pathway were identified: i.e., transformation of glycine to l-serine catalyzed by glycine hydroxymethyltransferase, and glycine synthase-catalyzed catabolism of glycine to N 5 , N 10 -methylene-tetrahydrofolic acid (THF), which reacts with another molecule of glycine to afford l-serine. l-Serine is transformed to acetyl-CoA via pyruvic acid. Acetyl-CoA enters the tricarboxylic acid cycle, affording 2-oxoglutaric acid, which in turn is transformed to l-glutamic acid. The l-glutamic acid enters the C5 pathway, affording ALA in A. hyalinus. A 13 C NMR spectroscopic comparison of the labeling patterns of Copro'gen III obtained after feeding of [2- 13 C]glycine, sodium [1- 13 C]acetate, and sodium [2- 13 C]acetate showed that [2- 13 C]glycine transformation and [2- 13 C]glycine catabolism in A. hyalinus proceed in the ratio of 52 and 48 %. The reaction of [2- 13 C]glycine and N 5 , N 10 -methylene-THF, that of glycine and N 5 , N 10 -[methylene- 13 C]methylene-THF generated from the [2- 13 C]glycine catabolism, and that of [2- 13 C]glycine and N 5 , N 10 -[methylene- 13 C]methylene-THF transformed the fed [2- 13 C]glycine to [1- 13 C]acetyl-CoA, [2- 13 C]acetyl-CoA, and [1,2- 13 C 2 ]acetyl-CoA in the ratios of 42, 37, and 21 %, respectively. These labeled acetyl-CoAs were then incorporated into ALA. Our results provide a quantitative picture of the pathways of biosynthetic transformation to ALA from glycine in A. hyalinus. (author)

  14. Isopiestic determination of the osmotic coefficient and vapour pressure of N-R-4-(N,N-dimethylamino)pyridinium tetrafluoroborate (R = C4H9, C5H11, C6H13) in the ethanol solution at T = 298.15 K

    International Nuclear Information System (INIS)

    Sardroodi, Jaber Jahanbin; Atabay, Maryam; Azamat, Jafar

    2012-01-01

    Highlights: ► The osmotic coefficients of the solutions of ionic liquid in ethanol have been measured. ► Measured osmotic coefficients were correlated using Pitzer, e-NRTL and NRF models and polynomial equation. ► Vapour pressures were evaluated from the correlated osmotic coefficients. - Abstract: Osmotic coefficients of the solutions of room temperature ionic liquid N-R-4-(N,N-dimethylamino)pyridinium tetrafluoroborate (R = C 4 H 9 , C 5 H 11 , C 6 H 13 ) in ethanol have been measured at T = 298.15 K by the isopiestic method. The experimental osmotic coefficients have been correlated using the ion interaction model of Pitzer, electrolyte non-random two liquid (e-NRTL) model of Chen, non-random factor (NRF) and a fourth-order polynomial in terms of molality. The vapour pressures of the solutions studied have been evaluated from the osmotic coefficients.

  15. Synthesis and crystal structure of new uranyl selenite(IV)-selenate(VI) [C5H14N][(UO2)3(SeO4)4(HSeO3)(H2O)](H2SeO3)(HSeO4)

    International Nuclear Information System (INIS)

    Krivovichev, S.V.; Tananaev, I.G.; Myasoedov, B.F.; Kalenberg, V.

    2006-01-01

    Crystals of new uranyl selenite(IV)-selenate(VI) [C 5 H 14 N][(UO 2 ) 3 (SeO 4 ) 4 (HSeO 3 )(H 2 O)](H 2 SeO 3 )(HSeO 4 ) are obtained by the method of evaporation from aqueous solutions. Compound has triclinic lattice, space group P1-bar, a=11.7068(9), b=14.8165(12), c=16.9766(15), α=73.899(6), β=76.221(7), γ=89.361(6) Deg, V=2743.0(4) A 3 , Z=2. Laminated complexes (UO 2 ) 3 (SeO 4 ) 4 (HSeO 3 )(H 2 O)] 3- are the basis of the structure. [HSe(VI)O 4 ] - , [H 2 Se(IV)O 3 ] complexes and protonated methylbutylamine cations are disposed between layers [ru

  16. Plant sterol metabolism. Δ7-Sterol-C5-Desaturase (STE1/DWARF7), Δ5,7-Sterol-Δ7-Reductase (DWARF5) and Δ24-Sterol-Δ24-Reductase (DIMINUTO/DWARF1) show multiple subcellular localizations in Arabidopsis thaliana (Heynh) L

    DEFF Research Database (Denmark)

    Silvestro, Daniele; Andersen, Tonni Grube; Schaller, Hubert

    2013-01-01

    in the corresponding enzymes. All fusion proteins were found to localize in the endoplasmic reticulum in functionally complemented plants. The results show that both ¿(5,7)-sterol-¿(7)-reductase and ¿(24)-sterol-¿(24)-reductase are in addition localized to the plasma membrane, whereas ¿(7)-sterol-C(5)-desaturase......Sterols are crucial lipid components that regulate membrane permeability and fluidity and are the precursors of bioactive steroids. The plant sterols exist as three major forms, free sterols, steryl glycosides and steryl esters. The storage of steryl esters in lipid droplets has been shown...... to contribute to cellular sterol homeostasis. To further document cellular aspects of sterol biosynthesis in plants, we addressed the question of the subcellular localization of the enzymes implicated in the final steps of the post-squalene biosynthetic pathway. In order to create a clear localization map...

  17. Translocation of an 89-kDa periplasmic protein is associated with Holospora infection

    International Nuclear Information System (INIS)

    Iwatani, Koichi; Dohra, Hideo; Lang, B. Franz; Burger, Gertraud; Hori, Manabu; Fujishima, Masahiro

    2005-01-01

    The symbiotic bacterium Holospora obtusa infects the macronucleus of the ciliate Paramecium caudatum. After ingestion by its host, an infectious form of Holospora with an electron-translucent tip passes through the host digestive vacuole and penetrates the macronuclear envelope with this tip. To investigate the underlying molecular mechanism of this process, we raised a monoclonal antibody against the tip-specific 89-kDa protein, sequenced this partially, and identified the corresponding complete gene. The deduced protein sequence carries two actin-binding motifs. Indirect immunofluorescence microscopy shows that during escape from the host digestive vacuole, the 89-kDa proteins translocates from the inside to the outside of the tip. When the bacterium invades the macronucleus, the 89-kDa protein is left behind at the entry point of the nuclear envelope. Transmission electron microscopy shows the formation of fine fibrous structures that co-localize with the antibody-labeled regions of the bacterium. Our findings suggest that the 89-kDa protein plays a role in Holospora's escape from the host digestive vacuole, the migration through the host cytoplasm, and the invasion into the macronucleus

  18. Characterization of a periplasmic S1-like nuclease coded by the Mesorhizobium loti symbiosis island

    International Nuclear Information System (INIS)

    Pimkin, Maxim; Miller, C. Glenn; Blakesley, Lauryn; Oleykowski, Catherine A.; Kodali, Nagendra S.; Yeung, Anthony T.

    2006-01-01

    DNA sequences encoding hypothetical proteins homologous to S1 nuclease from Aspergillus oryzae are found in many organisms including fungi, plants, pathogenic bacteria, and eukaryotic parasites. One of these is the M1 nuclease of Mesorhizobium loti which we demonstrate herein to be an enzymatically active, soluble, and stable S1 homolog that lacks the extensive mannosyl-glycosylation found in eukaryotic S1 nuclease homologs. We have expressed the cloned M1 protein in M. loti and purified recombinant native M1 to near homogeneity and have also isolated a homogeneous M1 carboxy-terminal hexahistidine tag fusion protein. Mass spectrometry and N-terminal Edman degradation sequencing confirmed the protein identity. The enzymatic properties of the purified M1 nuclease are similar to those of S1. At acidic pH M1 is 25 times more active on single-stranded DNA than on double-stranded DNA and 3 times more active on single-stranded DNA than on single-stranded RNA. At neutral pH the RNase activity of M1 exceeds the DNase activity. M1 nicks supercoiled RF-I plasmid DNA and rapidly cuts the phosphodiester bond across from the nick in the resultant relaxed RF-II plasmid DNA. Therefore, M1 represents an active bacterial S1 homolog in spite of great sequence divergence. The biochemical characterization of M1 nuclease supports our sequence alignment that reveals the minimal 21 amino acid residues that are necessarily conserved for the structure and functions of this enzyme family. The ability of M1 to degrade RNA at neutral pH implies previously unappreciated roles of these nucleases in biological systems

  19. CHITINASE-B FROM SERRATIA-MARCESCENS-BJL200 IS EXPORTED TO THE PERIPLASM WITHOUT PROCESSING

    NARCIS (Netherlands)

    BRURBERG, MB; EIJSINK, VGH; HAANDRIKMAN, AJ; VENEMA, G; NES, IF

    A gene encoding a chitinase from Serratia marcescens BJL200 was cloned and expressed in Escherichia coli and S. marcescens. Nucleotide sequencing revealed an open reading frame encoding a 55.5 kDa protein of 499 amino acids without a typical signal peptide for export. The cellular localization of

  20. Complement mediated renal inflammation induced by donor brain death : role of renal C5a-C5aR interaction

    NARCIS (Netherlands)

    van Werkhoven, M. B.; Damman, J.; van Dijk, M. C. R. F.; Daha, M. R.; de Jong, I. J.; Leliveld, A.; Krikke, C.; Leuvenink, H. G.; van Goor, H.; van Son, W. J.; Olinga, P.; Hillebrands, J. -L.; Seelen, M. A. J.

    Kidneys retrieved from brain-dead donors have impaired allograft function after transplantation compared to kidneys from living donors. Donor brain death (BD) triggers inflammatory responses, including both systemic and local complement activation. The mechanism by which systemic activated

  1. [Pr2(pdc3(Hpdc(H2O4]n·n(H3hp·8n(H2O, a One-Dimensional Coordination Polymer Containing PrO6N3 Tri-Capped Trigonal Prisms and PrO8N Mono-Capped Square Anti-Prisms (H2pdc = Pyridine 2,6-Dicarboxylic Acid, C7H5NO4; 3hp = 3-Hydroxy Pyridine, C5H5NO

    Directory of Open Access Journals (Sweden)

    Shahzad Sharif

    2012-08-01

    Full Text Available The synthesis, structure and some properties of the one-dimensional coordination polymer, [Pr2(pdc3(Hpdc]n·n(H3hp·8n(H2O, (H2pdc = pyridine 2,6-dicarboxylic acid, C7H5NO4; 3hp = 3-hydroxypyridine, C5H5NO are described. One of the Pr3+ ions is coordinated by two O,N,O-tridentate pdc2− ligands and one tridentate Hpdc− anion to generate a fairly regular PrO6N3 tri-capped trigonal prism, with the N atoms acting as the caps. The second Pr3+ ion is coordinated by one tridentate pdc2− dianion, four water molecules and two monodentate bridging pdc2− ligands to result in a PrO8N coordination polyhedron that approximates to a mono-capped square-anti-prism. The ligands bridge the metal-atom nodes into a chain, which extends in the [100] direction. The H3hp+ cation and uncoordinated water molecules occupy the inter-chain regions and an N–HLO and numerous O–HLO hydrogen bonds consolidate the structure. The H3hp+ species appears to intercalate between pendant pdc rings to consolidate the polymeric structure. Crystal data: 1 (C33H43N5O29Pr2, Mr = 1255.54, triclinic,  (No. 2, Z = 2, a = 13.2567(1 Å, b = 13.6304(2 Å, c = 13.6409(2 Å, α = 89.695(1°, β = 63.049(1°, γ = 86.105(1°, V = 2191.16(5 Å3, R(F = 0.033, wR(F2 = 0.084.

  2. The Influence of the Thymine C5 Methyl Group on Spontaneous Base Pair Breathing in DNA

    Czech Academy of Sciences Publication Activity Database

    Wärmländer, S.; Šponer, Jiří; Leijon, M.; Šponer, Judit E.

    2002-01-01

    Roč. 277, č. 32 (2002), s. 28491-28497 ISSN 0021-9258 R&D Projects: GA MŠk LN00A016 Institutional research plan: CEZ:AV0Z4040901 Keywords : thymine * DNA * base pairs Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 6.696, year: 2002

  3. Design and Discovery of Functionally Selective Serotonin 2C (5-HT2C) Receptor Agonists.

    Science.gov (United States)

    Cheng, Jianjun; McCorvy, John D; Giguere, Patrick M; Zhu, Hu; Kenakin, Terry; Roth, Bryan L; Kozikowski, Alan P

    2016-11-10

    On the basis of the structural similarity of our previous 5-HT 2C agonists with the melatonin receptor agonist tasimelteon and the putative biological cross-talk between serotonergic and melatonergic systems, a series of new (2,3-dihydro)benzofuran-based compounds were designed and synthesized. The compounds were evaluated for their selectivity toward 5-HT 2A , 5-HT 2B , and 5-HT 2C receptors in the calcium flux assay with the ultimate goal to generate selective 5-HT 2C agonists. Selected compounds were studied for their functional selectivity by comparing their transduction efficiency at the G protein signaling pathway versus β-arrestin recruitment. The most functionally selective compound (+)-7e produced weak β-arrestin recruitment and also demonstrated less receptor desensitization compared to serotonin in both calcium flux and phosphoinositide (PI) hydrolysis assays. We report for the first time that selective 5-HT 2C agonists possessing weak β-arrestin recruitment can produce distinct receptor desensitization properties.

  4. Effect of Copper on Passivity and Corrosion Behavior of Fe-xC-5Cu ...

    African Journals Online (AJOL)

    ... copper/microstructure is discussed. Alloying Cu showed a beneficial effect on hypoeutectoid steel and harmful effect on hypereutectoid steel. The improved corrosion resistance is related to cementite morphology and by a copper dissolution/re-deposition process. Keywords: Corrosion; Copper; cementite; EIS; Passivation ...

  5. Control and safety systems for TRIGA irradiation facilities C5 and C9

    International Nuclear Information System (INIS)

    Talpalariu Cornel Talpalariu Jeni Crucean Mircea Matei Corina

    2008-01-01

    Full text: The Institute for Nuclear Research conducted research for designing and manufacturing of microprocessor equipment for some irradiation facilities operating by the TRIGA reactor. This equipment has accumulated a wide operating time allowing the conclusions referring to reliability, ergonomics, and design of the operating facilities. Based upon these studies a new program was initiated for the design and manufacturing of a modern equipment with improved reliability and flexibility performances. The system provides the user with a multitude of options, numerical and analog interfaces, keyboard and high reliability local display. The main functional components of the system are: - 8 PID full options regulating loops; - 8 safety analog channels having 4 preset trips; - watch dog restart and fault tolerant facilities; - 8 high precision analog with an input of 0 - 15 mV from thermocouple; - 8 computer controlled power supplies of 220 V, 1 kWA; - alphanumeric display and keyboard; - fault tolerant analog scanner. A real improvement of the system is the future remote control computer, a PC AT Pentium working like a system controller, real time data acquisition, and operator's adviser. This new facility allows the operator to set the trips or to control remotely all the power supply and step-by-step positioner of irradiation device. Software design for acquisition and data processing provides modern techniques for operator interfacing, representation recording and protection of test results. Software implementation keeps a special organization supported by a real time executive that is the best method to achieve the performance required. Following this objective, the software structure consists of: 1. Tasks as follows: - testing parameters setup; - data processing routines; - engineering and electrical conversion; - numerical / graphical data representation; - test results recording routines and data base management. 2. Drivers as follows: - A/I and D/I acquisitions; - commands generation; - graphical positioning in screen pages; - peripheral communications management; - system time checking. This new concept can improve the availability precision and system safety and reduce personal irradiation. (authors)

  6. An efficient and facile synthesis of divergent C-3/C-5 bis ...

    Indian Academy of Sciences (India)

    extensive attention in organic synthesis and also serve as potential synthons for the ... plays an important role in synthetic chemistry, because they also serve as ...... scope, rate acceleration and selective formation of bis-. MBH adduct with ...

  7. 17 CFR 270.3c-5 - Beneficial ownership by knowledgeable employees and certain other persons.

    Science.gov (United States)

    2010-04-01

    ... Company. For purposes of this definition, the term “investment company” as used in section 2(a)(3) of the Act includes a Covered Company. (2) The term Covered Company means a Section 3(c)(1) Company or a... SECURITIES AND EXCHANGE COMMISSION (CONTINUED) RULES AND REGULATIONS, INVESTMENT COMPANY ACT OF 1940 § 270.3c...

  8. Classification of HTTP traffic based on C5.0 Machine Learning Algorithm

    DEFF Research Database (Denmark)

    Bujlow, Tomasz; Riaz, Tahir; Pedersen, Jens Myrup

    2012-01-01

    streaming through third-party plugins, etc. This paper suggests and evaluates two approaches to distinguish various types of HTTP traffic based on the content: distributed among volunteers' machines and centralized running in the core of the network. We also assess the accuracy of the centralized classifier...

  9. Plant MicroRNA Prediction by Supervised Machine Learning Using C5.0 Decision Trees

    Directory of Open Access Journals (Sweden)

    Philip H. Williams

    2012-01-01

    Full Text Available MicroRNAs (miRNAs are nonprotein coding RNAs between 20 and 22 nucleotides long that attenuate protein production. Different types of sequence data are being investigated for novel miRNAs, including genomic and transcriptomic sequences. A variety of machine learning methods have successfully predicted miRNA precursors, mature miRNAs, and other nonprotein coding sequences. MirTools, mirDeep2, and miRanalyzer require “read count” to be included with the input sequences, which restricts their use to deep-sequencing data. Our aim was to train a predictor using a cross-section of different species to accurately predict miRNAs outside the training set. We wanted a system that did not require read-count for prediction and could therefore be applied to short sequences extracted from genomic, EST, or RNA-seq sources. A miRNA-predictive decision-tree model has been developed by supervised machine learning. It only requires that the corresponding genome or transcriptome is available within a sequence window that includes the precursor candidate so that the required sequence features can be collected. Some of the most critical features for training the predictor are the miRNA:miRNA∗ duplex energy and the number of mismatches in the duplex. We present a cross-species plant miRNA predictor with 84.08% sensitivity and 98.53% specificity based on rigorous testing by leave-one-out validation.

  10. 29 CFR 2550.404c-5 - Fiduciary relief for investments in qualified default investment alternatives.

    Science.gov (United States)

    2010-07-01

    ..., transfer agent and similar administrative expenses), and are not imposed, or do not vary, based on a... accepted investment theories, is diversified so as to minimize the risk of large losses and that is... portfolio that applies generally accepted investment theories, is diversified so as to minimize the risk of...

  11. Binding of 14C-5-aminolevulinic acid to a stromal protein from developing pea chloroplasts

    International Nuclear Information System (INIS)

    Thayer, S.S.; Castelfranco, P.A.; Wilkinson, J.; Benson, G.

    1987-01-01

    14 -5-Aminolevulinic acid ( 14 C-ALA) binds to a stromal protein with an apparent molecular weight of 42-43 KD on LDS and non-denaturing gels. The reaction is rapid. Binding is inhibited by sulfhydryl reagents, mM concentrations of levulinic, dihydroxy heptanoic acids and gabaculine, 10 μM N-methylprotoporphyrin. Dicarboxilic acids, such as δKG, Glu, OAA, do not inhibit. Chloramphenicol, ATP, protoporphyrin, anoxia, light, darkness have no effect. The product, once formed, is stable to treatment with 5% conc. HCl in cold acetone. It can be chased in a second incubation with unlabeled ALA, but not with levulinic acid. No activity was detected in the subplastidic membrane fractions. Western blot analysis failed to reveal any homology between the labeled protein and either cytochrome for ALA dehydratase. This ALA-binding protein was not formed in chloroplasts isolated from fully expanded pea leaves. Therefore, it is deemed likely to participate in ALA metabolism during chloroplast development

  12. MMP mediated type V collagen degradation (C5M) is elevated in ankylosing spondylitis

    DEFF Research Database (Denmark)

    Veidal, S S; Larsen, D V; Chen, Xijuan

    2012-01-01

    Type V collagen has been demonstrated to control fibril formation. The aim of this study was to develop an ELISA capable of detecting a fragment of type V collagen generated by MMP-2/9 and to evaluate the assay as biomarker for ankylosing spondylitis (AS)....

  13. 26 CFR 31.3306(c)(5)-1 - Family employment.

    Science.gov (United States)

    2010-04-01

    ... this section, the exception is conditioned solely upon the family relationship between the employee and... partnership are not within the exception unless the requisite family relationship exists between the employee... relationship between the employee and the individual employing him. The exceptions are as follows: (1) Services...

  14. Plant MicroRNA Prediction by Supervised Machine Learning Using C5.0 Decision Trees.

    Science.gov (United States)

    Williams, Philip H; Eyles, Rod; Weiller, Georg

    2012-01-01

    MicroRNAs (miRNAs) are nonprotein coding RNAs between 20 and 22 nucleotides long that attenuate protein production. Different types of sequence data are being investigated for novel miRNAs, including genomic and transcriptomic sequences. A variety of machine learning methods have successfully predicted miRNA precursors, mature miRNAs, and other nonprotein coding sequences. MirTools, mirDeep2, and miRanalyzer require "read count" to be included with the input sequences, which restricts their use to deep-sequencing data. Our aim was to train a predictor using a cross-section of different species to accurately predict miRNAs outside the training set. We wanted a system that did not require read-count for prediction and could therefore be applied to short sequences extracted from genomic, EST, or RNA-seq sources. A miRNA-predictive decision-tree model has been developed by supervised machine learning. It only requires that the corresponding genome or transcriptome is available within a sequence window that includes the precursor candidate so that the required sequence features can be collected. Some of the most critical features for training the predictor are the miRNA:miRNA(∗) duplex energy and the number of mismatches in the duplex. We present a cross-species plant miRNA predictor with 84.08% sensitivity and 98.53% specificity based on rigorous testing by leave-one-out validation.

  15. Public-Private Competitions: Processes Used for C-5 Aircraft Award Appear Reasonable

    National Research Council Canada - National Science Library

    1998-01-01

    .... To mitigate the impact of the closings on the local communities and employees, the administration announced its intention to maintain employment levels by privatizing the depots workloads in place...

  16. New cultive medium for bioconversion of C5 fraction from sugarcane bagasse using rice bran extract

    Directory of Open Access Journals (Sweden)

    Debora Danielle Virginio da Silva

    2014-12-01

    Full Text Available The use of hemicellulosic hydrolysates in bioprocesses requires supplementation as to ensure the best fermentative performance of microorganisms. However, in light of conflicting data in the literature, it is necessary to establish an inexpensive and applicable medium for the development of bioprocesses. This paper evaluates the fermentative performance of Scheffersomyces (Pichia stipitis and Candida guilliermondii growth in sugarcane bagasse hemicellulosic hydrolysate supplemented with different nitrogen sources including rice bran extract, an important by-product of agroindustry and source of vitamins and amino acids. Experiments were carried out with hydrolysate supplemented with rice bran extract and (NH42SO4; peptone and yeast extract; (NH42SO4, peptone and yeast extract and non-supplemented hydrolysate as a control. S. stipitis produced only ethanol, while C. guilliermondii produced xylitol as the main product and ethanol as by-product. Maximum ethanol production by S. stipitis was observed when sugarcane bagasse hemicellulosic hydrolysate was supplemented with (NH42SO4, peptone and yeast extract. Differently, the maximum xylitol formation by C. guilliermondii was obtained by employing hydrolysate supplemented with (NH42SO4 and rice bran extract. Together, these findings indicate that: a for both yeasts (NH42SO4 was required as an inorganic nitrogen source to supplement sugarcane bagasse hydrolysate; b for S. stipitis, sugarcane hemicellulosic hydrolysate must be supplemented with peptone and yeast extract as organic nitrogen source; and: c for C. guilliermondii, it must be supplemented with rice bran extract. The present study designed a fermentation medium employing hemicellulosic hydrolysate and provides a basis for studies about value-added products as ethanol and xylitol from lignocellulosic materials.

  17. Strategic Airlift Modernization: Analysis of C-5 Modernization and C-17 Acquisition Issues

    Science.gov (United States)

    2008-04-15

    shaped more like an aircraft’s wing, to generate lift through aerodynamic forces. Advocates hope airships may be capable of carrying a complete Army...airships use aerodynamic lift and will take-off and land much like conventional aircraft. Some estimate that 1,000 ton-class hybrid aircraft will require...Description153 Power plant: Four Pratt & Whitney F117-PW-100 turbofan engines Wingspan: 169 feet 10 inches (to winglet tips) (51.76 meters) Length: 174

  18. Wet effluent diffusion technique and determination of C1-C5 alcohols in air

    Czech Academy of Sciences Publication Activity Database

    Sklenská, Jana; Pařízek, Petr; Večeřa, Zbyněk

    2001-01-01

    Roč. 8, č. 1 (2001), s. 121-127 ISSN 1231-7098 R&D Projects: GA ČR GA203/98/0943 Grant - others:COPERNICUS(BE) SUB-AERO EVK2-1999-000327 Institutional research plan: CEZ:AV0Z4031919 Keywords : wet effluent difussion denuder * determination * air Subject RIV: CB - Analytical Chemistry, Separation

  19. Project W-320, 241-C-106 sluicing: Construction specification W-320-C5

    Energy Technology Data Exchange (ETDEWEB)

    Bailey, J.W.

    1998-07-20

    This supporting document has been prepared to make the construction specifications for Project W-320 readily available. Project W-320, Waste Retrieval Sluicing System (WRSS), specification is for procurement, fabrication and installation of equipment at the C Tank Farm, including Operator Station and some equipment just outside the C Tank Farm fence, necessary to support the sluicing operation. Work consists of furnishing labor, equipment, and materials to provide the means to procure materials and equipment, fabricate items, excavate and place concrete, and install equipment, piping, wiring, and structures in accordance with the Contract Documents. Major work elements include: Excavation for process and fire protection piping, electrical conduit trenches, and foundations for small structures; Placement of concrete cover blocks, foundations, and equipment pads; Procurement and installation of double walled piping, electrical conduit, fire and raw water piping, chilled water piping, and electrical cable; Procurement and installation of above-ground ventilation system piping between the (HVAC) Process building and Tank C-106; Core drill existing concrete; Furnish and installation of electrical distribution equipment; Installation of the concrete foundation, and assembly installation of the two Seismic Shutdown Systems with Environmental Enclosures; Fabrication and installation of in-pit pipe jumpers, including related valves, instruments and wiring; and Installation of a vertical submersible pump, horizontal booster pump, and winch assembly into tank access riser pits.

  20. Project W-320, 241-C-106 sluicing: Construction specification W-320-C5

    International Nuclear Information System (INIS)

    Bailey, J.W.

    1998-01-01

    This supporting document has been prepared to make the construction specifications for Project W-320 readily available. Project W-320, Waste Retrieval Sluicing System (WRSS), specification is for procurement, fabrication and installation of equipment at the C Tank Farm, including Operator Station and some equipment just outside the C Tank Farm fence, necessary to support the sluicing operation. Work consists of furnishing labor, equipment, and materials to provide the means to procure materials and equipment, fabricate items, excavate and place concrete, and install equipment, piping, wiring, and structures in accordance with the Contract Documents. Major work elements include: Excavation for process and fire protection piping, electrical conduit trenches, and foundations for small structures; Placement of concrete cover blocks, foundations, and equipment pads; Procurement and installation of double walled piping, electrical conduit, fire and raw water piping, chilled water piping, and electrical cable; Procurement and installation of above-ground ventilation system piping between the (HVAC) Process building and Tank C-106; Core drill existing concrete; Furnish and installation of electrical distribution equipment; Installation of the concrete foundation, and assembly installation of the two Seismic Shutdown Systems with Environmental Enclosures; Fabrication and installation of in-pit pipe jumpers, including related valves, instruments and wiring; and Installation of a vertical submersible pump, horizontal booster pump, and winch assembly into tank access riser pits

  1. C5-Alkynyl-Functionalized ?-L-LNA: Synthesis, Thermal Denaturation Experiments and Enzymatic Stability

    OpenAIRE

    Kumar, Pawan; Baral, Bharat; Anderson, Brooke A.; Guenther, Dale C.; ?stergaard, Michael E.; Sharma, Pawan K.; Hrdlicka, Patrick J.

    2014-01-01

    Major efforts are currently being devoted to improving the binding affinity, target specificity, and enzymatic stability of oligonucleotides used for nucleic acid targeting applications in molecular biology, biotechnology, and medicinal chemistry. One of the most popular strategies toward this end has been to introduce additional modifications to the sugar ring of affinity-inducing conformationally restricted nucleotide building blocks such as locked nucleic acid (LNA). In the preceding artic...

  2. Sampling and analysis plan for the 116-C-5 retention basins characteristic dangerous waste determination

    International Nuclear Information System (INIS)

    Bauer, R.G.; Dunks, K.L.

    1996-03-01

    Cooling water flow from the rear face of the 100-B and 100-C reactors was diverted to large retention basins prior to discharge to the Columbia River. These retention basins delayed the release of the reactor coolant for decay of the short-lived activation products and for thermal cooling. Some of the activation products were deposited in sludge that settled in the basins and discharge lines. In addition, some contamination was deposited in soil around the basins and associated piping. The sampling objective of this project is to determine if regulated levels of leachable lead are present in the abrasive materials used to decontaminate the retention basin tank walls, in the material between the tank base plate and the concrete foundation, and in the soils immediately surrounding the perimeter of the retention basins. Sampling details, including sampling locations, frequencies, and analytical requirements, are discussed. Also described is the quality assurance plan for this project

  3. Fall and rise of satellite repeats in allopolyploids of Nicotiana over c. 5 million years

    Czech Academy of Sciences Publication Activity Database

    Koukalová, Blažena; Moraes, A.P.; Renny-Byfield, S.; Matyášek, Roman; Leitch, A.R.; Kovařík, Aleš

    2010-01-01

    Roč. 186, č. 1 (2010), s. 148-160 ISSN 0028-646X R&D Projects: GA ČR(CZ) GA521/07/0116 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : concerted evolution * interlocus homogenization * Nicotiana Subject RIV: BO - Biophysics Impact factor: 6.516, year: 2010

  4. Resolving the Two-Electron Process for the Couple [(C5Me5)M(N

    Czech Academy of Sciences Publication Activity Database

    Kaim, W.; Reinhardt, R.; Greulich, S.; Fiedler, Jan

    2003-01-01

    Roč. 22, - (2003), s. 2240-2244 ISSN 0276-7333 R&D Projects: GA ČR GA203/03/0821 Institutional research plan: CEZ:AV0Z4040901 Keywords : electrochemical generation * iridium (III) complexes * bridging ligands Subject RIV: CG - Electrochemistry Impact factor: 3.375, year: 2003

  5. 26 CFR 1.642(c)-5 - Definition of pooled income fund.

    Science.gov (United States)

    2010-04-01

    ... participation will fluctuate with each new transfer of property to the fund in relation to the appreciation or depreciation in the fair market value of the property in the fund, but all units in the fund will always have... initial fair market value; the instrument also provides that the income allocable to appreciation in the...

  6. 26 CFR 1.1402(c)-5 - Ministers and members of religious orders.

    Science.gov (United States)

    2010-04-01

    ... taken a vow of poverty as a member of such order) may elect, as provided in § 1.1402(e)(1)-1, to have... member of a religious order (other than a member of a religious order who has taken a vow of poverty as a... advisory service to Y Company in connection with the publication of a book dealing with the history of M's...

  7. Engineering Brevibacterium flavum for the production of renewable bioenergy: C4-C5 advanced alcohols.

    Science.gov (United States)

    Su, HaiFeng; Lin, JiaFu; Wang, YuanHong; Chen, Qiao; Wang, GuangWei; Tan, FuRong

    2017-09-01

    Biosynthesis of advanced biofuels by engineered non-natural microorganisms has been proposed to be the most promising approach for the replacement of dwindling fossil fuel resources. Brevibacterium flavum (Bf) is a model brevibacterium aerobe which lacks basic and applied research that could enable this species to produce biofuels. There are no reports regarding engineering this microorganism to produce advanced alcohols before. Here, for the first time, we developed the bacterium as a novel biosynthetic platform for advanced alcohols production via the mutagenesis and engineering to produce 2-ketoacids derived alcohols. In order to enhance the strain's capability of producing advanced alcohols, we preferentially improved intrinsic metabolism ability of the strain to obtain improved expression host (IEH) via generating mutagenesis libraries by whole cell mutagenesis (WCM). The IEH was determined via screening out the mutant strain with the highest production of branched-chain organic acids (BCOA) using high throughput screening method.. Subsequently, a novel vector system for Bf was established, and the corresponding biosynthetic pathway of directing carbon flux into the target advanced alcohols was recruited to make the bacterium possess the capability of producing advanced alcohols and further enhance the production using the IEH. Specifically, we generated bioengineered strains that were able to synthesize up to the highest 5362 and 4976 mg/L isobutanol, 1945 and 1747 mg/L 2-methyl-1-butanol (2 MB), and 785.34 and 781 mg/L 3-methyl-1-butanol (3 MB) from pure glucose and duckweed substrates, respectively. Our findings confirmed the feasibility and potential of using Bf as a novel biosynthetic platform to generate advanced biofuels with glucose and inexpensive renewable feedstock-duckweed as a fermentation substrate. Biotechnol. Bioeng. 2017;114: 1946-1958. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  8. 26 CFR 1.414(c)-5 - Certain tax-exempt organizations.

    Science.gov (United States)

    2010-04-01

    ... circumstances. To illustrate the rules of this paragraph (b), if exempt organization A has the power to appoint... other form; and (B) Such treatment would be consistent with the anti-abuse standards in paragraph (f) of... percent of the trustees of either organization. Organization O has the power to remove any of the trustees...

  9. Acquisition Management: Source Selection Procedures for the C-5 Avionics Modernization Program

    National Research Council Canada - National Science Library

    Granetto, Paul J; Neville, Douglas P; Mathews, Amy L; Thompson, Lashonda M; Burger, Michael T; Anderson, Lamar; Hepler, Michael T; Borrero, Karen M; Hart, Erin S

    2006-01-01

    ... (Acquisition, Technology, and Logistics) commissioned a study to review acquisition-related actions taken by the former Principal Deputy Assistant Secretary of the Air Force for Acquisition and Management (Principal Deputy...

  10. Type IX secretion system PorM and gliding machinery GldM form arches spanning the periplasmic space

    OpenAIRE

    Leone, Philippe; Roche, Jennifer; Vincent, Maxence S.; Tran, Quang Hieu; Desmyter, Aline; Cascales, Eric; Kellenberger, Christine; Cambillau, Christian; Roussel, Alain

    2018-01-01

    Type IX secretion system (T9SS), exclusively present in the Bacteroidetes phylum, has been studied mainly in Flavobacterium johnsoniae and Porphyromonas gingivalis. Among the 18 genes, essential for T9SS function, a group of four, porK-N (P. gingivalis) or gldK-N (F. johnsoniae) belongs to a co-transcribed operon that expresses the T9SS core membrane complex. The central component of this complex, PorM (or GldM), is anchored in the inner membrane by a trans-membrane helix and interacts throug...

  11. Comparison of different methods of osmotic shocks for extraction of Human Granulocyte Colony Stimulating Factor produced in periplasm

    Directory of Open Access Journals (Sweden)

    Sharareh Peymanfar

    2018-06-01

    Discussion and conclusion: Regarding the results, it is concluded that the MgSO4 with Tris buffer create a good osmotic pressure and accordingly is a more effective way for G-CSF protein extraction. As a result, this method could be used for production and simple separation of recombinant drug proteins.

  12. Transcriptomic analysis of swarm motility phenotype of Salmonella enterica serovar Typhimurium mutant defective in periplasmic glucan synthesis

    Science.gov (United States)

    Movement of food-borne pathogens on moist surfaces enables them to migrate towards more favorable niches and facilitate their survival for extended periods of time. Salmonella enterica serovar Typhimurium mutants defective in OPG synthesis are unable to exhibit motility on moist surfaces (swarming) ...

  13. The structure of BVU2987 from Bacteroides vulgatus reveals a superfamily of bacterial periplasmic proteins with possible inhibitory function

    International Nuclear Information System (INIS)

    Das, Debanu; Finn, Robert D.; Carlton, Dennis; Miller, Mitchell D.; Abdubek, Polat; Astakhova, Tamara; Axelrod, Herbert L.; Bakolitsa, Constantina; Chen, Connie; Chiu, Hsiu-Ju; Chiu, Michelle; Clayton, Thomas; Deller, Marc C.; Duan, Lian; Ellrott, Kyle; Ernst, Dustin; Farr, Carol L.; Feuerhelm, Julie; Grant, Joanna C.; Grzechnik, Anna; Han, Gye Won; Jaroszewski, Lukasz; Jin, Kevin K.; Klock, Heath E.; Knuth, Mark W.; Kozbial, Piotr; Krishna, S. Sri; Kumar, Abhinav; Marciano, David; McMullan, Daniel; Morse, Andrew T.; Nigoghossian, Edward; Nopakun, Amanda; Okach, Linda; Puckett, Christina; Reyes, Ron; Rife, Christopher L.; Sefcovic, Natasha; Tien, Henry J.; Trame, Christine B.; Bedem, Henry van den; Weekes, Dana; Wooten, Tiffany; Xu, Qingping; Hodgson, Keith O.; Wooley, John; Elsliger, Marc-André; Deacon, Ashley M.; Godzik, Adam; Lesley, Scott A.; Wilson, Ian A.

    2010-01-01

    The crystal structure of the BVU2987 gene product from B. vulgatus (UniProt A6L4L1) reveals that members of the new Pfam family PF11396 (domain of unknown function; DUF2874) are similar to β-lactamase inhibitor protein and YpmB. Proteins that contain the DUF2874 domain constitute a new Pfam family PF11396. Members of this family have predominantly been identified in microbes found in the human gut and oral cavity. The crystal structure of one member of this family, BVU2987 from Bacteroides vulgatus, has been determined, revealing a β-lactamase inhibitor protein-like structure with a tandem repeat of domains. Sequence analysis and structural comparisons reveal that BVU2987 and other DUF2874 proteins are related to β-lactamase inhibitor protein, PepSY and SmpA-OmlA proteins and hence are likely to function as inhibitory proteins

  14. Periplasmic Cytochrome c(3) of Desulfovibrio vulgaris Is Directly Involved in H2-Mediated Metal but Not Sulfate Reduction

    International Nuclear Information System (INIS)

    Elias, Dwayne A.; Suflita, Joseph M.; McInerney, Michael J.; Krumholz, Lee R.

    2004-01-01

    Kinetic parameters and the role of cytochrome c3 in sulfate, Fe(III), and U(VI) reduction were investigated in Desulfovibrio vulgaris Hildenborough. While sulfate reduction followed Michaelis-Menten kinetics (Km 220 uM), loss of Fe(III) and U(VI) was first-order at all concentrations tested. Initial reduction rates of all electron acceptors were similar for cells grown with H2 and sulfate, while cultures grown using lactate and sulfate had similar rates of metal loss but lower sulfate reduction activities. The similarities in metal, but not sulfate, reduction with H2 and lactate suggest divergent pathways. Respiration assays and reduced minus oxidized spectra were carried out to determine c-type cytochrome involvement in electron acceptor reduction. c-type cytochrome oxidation was immediate with Fe(III) and U(VI) in the presence of H2, lactate, or pyruvate. Sulfidogenesis occurred with all three electron donors and effectively oxidized the c-type cytochrome in lactate or pyruvate-reduced, but not H2-reduced cells. Correspondingly, electron acceptor competition assays with lactate or pyruvate as electron donors showed that Fe(III) inhibited U(VI) reduction, and U(VI) inhibited sulfate loss. However, sulfate reduction was slowed but not halted when H2 was the electron donor in the presence of Fe(III) or U(VI). U(VI) loss was still impeded by Fe(III) when H2 was used. Hence, we propose a modified pathway for the reduction of sulfate, Fe(III), and U(VI) which helps explain why these bacteria cannot grow using these metals. We further propose that cytochrome c3 is an electron carrier involved in lactate and pyruvate oxidation and is the reductase for alternate electron acceptors with higher redox potentials than sulfate

  15. Report on fiscal 2000 geothermal development promotion survey. No. C-5 Appi district environmental impact survey (1st phase); 2000 nendo chinetsu kaihatsu sokushin chosa hokokusho - No.C-5. 1. Appi chiiki kankyo eikyo chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-08-01

    For the survey of weather in the Appi district, Iwate Prefecture, observation data covering the last decade were collected at weather stations and the like, and characteristics of weather, climate, and natural earthquakes were learned. In the survey of fluctuation in the spa water level, studies were made about fluctuation in water temperature, spring water, and river water, and basic data were collected for the examination of the impact to be generated by geothermal exploration well boring and short-term discharge tests. In the survey of animal and vegetables, the habitation and distribution of animals and vegetables at sites planned for geothermal well boring were investigated, and data were collected for the evaluation of the impact to be imposed on them by well boring or the like. In the survey dealing with nature conservation and landscape, laws and regulations governing nature conservation were collected and put in an easy-to-use order, and seasonal changes in the natural landscape were photographed and recorded. In the survey of noise/vibration and ground fluctuation, the background values were measured prior to the implementation of geothermal well boring, discharge tests, and so forth. (NEDO)

  16. Air-tolerant C–C bond formation via organometallic ruthenium catalysis: diverse catalytic pathways involving (C5Me5)Ru or (C5H5)Ru are robust to molecular oxygen

    Czech Academy of Sciences Publication Activity Database

    Severa, Lukáš; Vávra, Jan; Kohoutová, Anna; Čížková, Martina; Šálová, Tereza; Hývl, Jakub; Šaman, David; Pohl, Radek; Adriaenssens, Louis; Teplý, Filip

    2009-01-01

    Roč. 50, č. 31 (2009), s. 4526-4528 ISSN 0040-4039 Institutional research plan: CEZ:AV0Z40550506 Keywords : ruthenium * organometallic catalysis * [2+2+2] cycloaddition * terminal alkynes Subject RIV: CC - Organic Chemistry Impact factor: 2.660, year: 2009

  17. Penerapan Total Productive Maintenance dengan menggunakan metode OEE pada turbin uap Type C5 DS II – GVS

    Directory of Open Access Journals (Sweden)

    Joel Bastanta Perangin Angin

    2018-01-01

    Full Text Available Abstrak Secara harfiah, tidak ada barang ataupun benda buatan manusia yang tidak dapat rusak, mesin turbin uap misalnya. Namun kerusakan tersebut dapat dicegah dengan metode perawatan yang tepat demi masa pakai yang lebih lama. Penelitian ini menganalisis tentang penerapan Total Productive Maintenace (TPM pada mesin turbin uap untuk peningkatan produktivitas dengan menggunakan metode Overall Equipment Efectiveness (OEE di PT PP London Sumatera Indonesia, tbk. Didalam analisis TPM dengan menggunakan metode OEE ini ada terdapat enam penyebab kerugian yang disebut dengan Six Big Losses yaitu diantaranya : kerusakan peralatan, persiapan peralatan, gangguan kecil dan waktu nganggur, kecepatan rendah, cacat produk dalam proses, hasil rendah.Kesimpulan yang didapat adalah nilai rata – rata OEE selama tahun 2015 adalah 65,08 % masih dibawah standar. Nilai gangguan kecil dan waktu nganggur 85,44 % dengan total waktu 2449,54 jam, hasilCacat produk dalam proses2,52 % dengan total waktu 72,12 jam, hasilKecepatan rendah 11,58 % dengan total waktu 331,88 jam, hasil Kerusakan peralatan0,38 % dengan total waktu 11 jam, hasil Persiapan peralatan 0,08 % dengan total waktu 2,41 jam, hasil Hasil rendah 0. Kata kunci: Total Productive Maintenance, Overall Equipment Effectiveness, Six Big Losses,Maintenance, Turbin Uap Abstract Generally, there is nothing properties hand made without damaging, steam turbine engines as an example. But the damage can be prevent by the precise method maintenance in the machines for the long life time. This study analyzes the application of Total Productive Maintenance (TPM at the steam turbine machinery to increase productivity by using the method Overall Equipment Effectiveness (OEE. In the analysis of TPM using OEE there are six causes of loss called Six Big Losses, such as: damage to equipment ( breakdown losses , preparation of equipment ( set- up and adjustment , disorders of the small and idle time ( idling and minor stoppages low speed ( speed reduced losses , defective products in the process ( rework losses , lower results (yield / scrap losses. The conclusion is the value - average OEE for 2015 is 65.08 % is below standard. The Value of Idling / Minor Stoppages Losses is 85.44 % with a total time of 2449.54 hours, the results of Yield / Scrap losses is 2.52 % with a total time of 72.12 hours, the results of Reduce Speed Losses 11.58 % with a total time of 331.88 hours, the results of Breakdown Losses is 0.38 % with a total time of 11 hours, the results Setup and Adjustment Losses is 0.08 % with a total time of 2.41 hours, the results of Rework Losses 0. Keywords: Total Productive Maintenance, Overall Equipment Effectiveness, Six Big Losses,Maintenance, Turbin Uap

  18. Estimating the Cerenkov neutron sensitivity of Suprasil (SiO2) and Lucite (C5H8O2)

    International Nuclear Information System (INIS)

    Clark, D.

    1982-01-01

    Fast neutrons hitting a sample of suprasil will produce light. This light is Cerenkov light produced by high energy (> .2 MeV) electrons traversing the transparent medium. Neutrons produce these electrons in a two step process. First, the neutrons inelastically scatter with either the silicon (Si) or the oxygen (O) atoms producing inelastic gamma rays. Some of these gammas, in turn, will also react producing, primarily, Compton electrons with some pair production electrons possible. The majority of these Compton electrons will have enough energy to induce Cerenkov light production. For intermediate energy neutrons (2 to 20 MeV), this process is efficient enough to produce a relatively simple neutron detector with some desirable properties. Estimations of the Cherenkov/neutron sensitivities of suprasil and lucite are presented

  19. TM0416, a Hyperthermophilic Promiscuous Nonphosphorylated Sugar Isomerase, Catalyzes Various C5 and C6 Epimerization Reactions.

    Science.gov (United States)

    Shin, Sun-Mi; Cao, Thinh-Phat; Choi, Jin Myung; Kim, Seong-Bo; Lee, Sang-Jae; Lee, Sung Haeng; Lee, Dong-Woo

    2017-05-15

    There is currently little information on nonphosphorylated sugar epimerases, which are of potential interest for producing rare sugars. We found a gene (the TM0416 gene) encoding a putative d-tagatose-3-epimerase-related protein from the hyperthermophilic bacterium Thermotoga maritima We overexpressed the TM0416 gene in Escherichia coli and purified the resulting recombinant protein for detailed characterization. Amino acid sequence alignment and a structural similarity search revealed that TM0416 is a putative nonphosphorylated sugar epimerase. The recombinant enzyme exhibited maximal C-3 epimerization of l-ribulose to l-xylulose at ∼80°C and pH 7 in the presence of 1 mM Mn 2+ In addition, this enzyme showed unusually high activity for the epimerization of d-tagatose to d-sorbose, with a conversion yield of 20% after 6 h at 80°C. Remarkably, the enzyme catalyzed the isomerization of d-erythrose or d-threose to d-erythrulose significantly, with conversion yields of 71% and 54.5%, respectively, after 6 h at 80°C at pH 7. To further investigate the substrate specificity of TM0416, we determined its crystal structures in complex with divalent metal ions and l-erythrulose at resolutions of 1.5 and 1.6 Å. Detailed inspection of the structural features and biochemical data clearly demonstrated that this metalloenzyme, with a freely accessible substrate-binding site and neighboring hydrophobic residues, exhibits different and promiscuous substrate preferences, compared with its mesophilic counterparts. Therefore, this study suggests that TM0416 can be functionally classified as a novel type of l-ribulose 3-epimerase (R3E) with d-erythrose isomerase activity. IMPORTANCE Rare sugars, which occur naturally in small amounts, have attracted considerable attention in the food and drug industries. However, there is little information on nonphosphorylated sugar epimerases, which might potentially be applied for the production of rare sugars. This study describes the characterization and functional annotation of a putative nonphosphorylated sugar 3-epimerase from a hyperthermophilic bacterium. Furthermore, we determined its crystal structures in complex with divalent metal ions and l-erythrulose, highlighting its metal-dependent, bifunctional, sugar-isomerizing activity. This hyperthermophilic R3E exhibited d-erythrose/d-threose isomerase activity, with structural features near the substrate-binding site distinct from those of its mesophilic counterparts. Moreover, this metalloenzyme showed unusually high activity for the epimerization of d-tagatose to d-sorbose at 70°C. Therefore, TM0416 can be functionally classified as a novel type of promiscuous R3E with a potential for the production of rare sugars for the food and pharmaceutical industries. Copyright © 2017 American Society for Microbiology.

  20. Self-Assembly of Amphiphilic Block Copolypeptoids with C 2 -C 5 Side Chains in Aqueous Solution

    KAUST Repository

    Fetsch, Corinna

    2014-12-22

    © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Nowadays, amphiphilic molecules play an important role in our life. In medical applications, amphiphilic block copolymers have attracted much attention as excipients in drug delivery systems. Here, the polymers are used as emulsifiers, micelles, or polymersomes with a hydrophilic corona block and a hydrophobic core or membrane. The aggregation behavior in aqueous solutions of a series of different amphiphilic block copolypeptoids comprising polysarcosine as a hydrophilic part is here reported. The formation of aggregates is investigated with 1H NMR spectroscopy and dynamic light scattering, and the determination of the critical micelle concentration (cmc) is performed using pyrene fluorescence spectroscopy. For the different block copolypeptoids cmc values ranging from 0.6 × 10-6 M to 0.1 × 10-3 M are found. The tendency to form micelles increases with increasing hydrophobicity at the nitrogen side chain in the hydrophobic moiety. Furthermore, in the case of the same hydrophobic side chain, a decreasing hydrophilic/lipophilic balance leads to the formation of larger aggregates. The aggregates formed in the buffer are able to solubilize the hydrophobic model compounds Reichardt\\'s dye and pyrene, and exhibit versatile microenvironments. Final investigations about the cytotoxicity reveal that the block copolypeptoids are well tolerated by mammalian cells up to high concentrations.

  1. Global Erratum for Kepler Q0-Q17 and K2 C0-C5 Short Cadence Data

    Science.gov (United States)

    Caldwell, Douglas; Van Cleve, Jeffrey E.

    2016-01-01

    An accounting error has scrambled much of the short-cadence collateral smear data used to correct for the effects of Keplers shutterless readout. This error has been present since launch and affects approximately half of all short-cadence targets observed by Kepler and K2 to date. The resulting calibration errors are present in both the short-cadence target pixel files and the short-cadence light curves for Kepler Data Releases 1-24 and K2 Data Releases 1-7. This error does not affect long-cadence data. Since it will take some time to correct this error and reprocess all Kepler and K2 data, a list of affected targets is provided. Even though the affected targets are readily identified, the science impact for any particular target may be difficult to assess. Since the smear signal is often small compared to the target signal, the effect is negligible for many targets. However, the smear signal is scene-dependent, so time varying signals can be introduced into any target by the other stars falling on the same CCD column. Some tips on how to assess the severity of the calibration error are provided in this document.

  2. Characterization of the stoichiometry of the complex formed by Staphylococcal toxin LukSF and human C5a receptor

    NARCIS (Netherlands)

    Haapasalo-Tuomainen, Karita; Wollman, Adam; De Haas, Carla; Aerts, Piet; Van'T Veld, Esther; Strijbis, Karin; Wubbolts, Richard; Van Kessel, Kok; Leake, Mark; Van Strijp, Jos

    2016-01-01

    Staphylococcus aureus causes diseases ranging from superficial skin and soft tissue infections (SSTI) to severe invasive diseases like osteomyelitis and necrotizing pneumonia. Panton Valentine Leukocidin (PVL) is a powerful leukocidal toxin produced by multiple S. aureus isolates. It is a pro-phage

  3. Adsorption of tentacled tetragonal star connectors, C4R4-Co-C-5(HgX)(5), on mercury

    Czech Academy of Sciences Publication Activity Database

    Pospíšil, Lubomír; Varaksa, N.; Magnera, T. F.; Brotin, T.; Michl, Josef

    2007-01-01

    Roč. 23, č. 2 (2007), s. 930-935 ISSN 0743-7463 R&D Projects: GA MŠk LC510; GA MŠk OC 140; GA MŠk ME 857; GA AV ČR IAA400400505 Grant - others:USARO(US) W911NF-05-0535; NSF(US) OISE 0532040 Institutional research plan: CEZ:AV0Z40400503 Source of funding: V - iné verejné zdroje ; V - iné verejné zdroje Keywords : air water interface * square-grid polymer * potential sweep voltammetry * electrochemistry Subject RIV: CG - Electrochemistry Impact factor: 4.009, year: 2007

  4. Employ Simulation Techniques. Second Edition. Module C-5 of Category C--Instructional Execution. Professional Teacher Education Module Series.

    Science.gov (United States)

    Ohio State Univ., Columbus. National Center for Research in Vocational Education.

    One of a series of performance-based teacher education learning packages focusing upon specific professional competencies of vocational teachers, this learning module deals with employing simulation techniques. It consists of an introduction and four learning experiences. Covered in the first learning experience are various types of simulation…

  5. Environmental Assessment. Beddown of a C-5M Super Galaxy Formal Training Unit, Dover Air Force Base

    Science.gov (United States)

    2011-03-01

    operations and maintenance OSHA Occupational Safety and Health Administration Pb lead PCE tetrachloroethylene PM10 particulate matter measuring...Korea, Malaysia , Pakistan, or the Philippine Islands; and • Native Hawaiian and Other Pacific Islanders – A person having origins in any of the...near operating facilities. 3.9.1.1 Occupational Health and Safety The Occupational Safety and Health Administration ( OSHA ) program’s purpose is to

  6. Temporal expansion of annual crop classification layers for the CONUS using the C5 decision tree classifier

    Science.gov (United States)

    Friesz, Aaron M.; Wylie, Bruce K.; Howard, Daniel M.

    2017-01-01

    Crop cover maps have become widely used in a range of research applications. Multiple crop cover maps have been developed to suite particular research interests. The National Agricultural Statistics Service (NASS) Cropland Data Layers (CDL) are a series of commonly used crop cover maps for the conterminous United States (CONUS) that span from 2008 to 2013. In this investigation, we sought to contribute to the availability of consistent CONUS crop cover maps by extending temporal coverage of the NASS CDL archive back eight additional years to 2000 by creating annual NASS CDL-like crop cover maps derived from a classification tree model algorithm. We used over 11 million records to train a classification tree algorithm and develop a crop classification model (CCM). The model was used to create crop cover maps for the CONUS for years 2000–2013 at 250 m spatial resolution. The CCM and the maps for years 2008–2013 were assessed for accuracy relative to resampled NASS CDLs. The CCM performed well against a withheld test data set with a model prediction accuracy of over 90%. The assessment of the crop cover maps indicated that the model performed well spatially, placing crop cover pixels within their known domains; however, the model did show a bias towards the ‘Other’ crop cover class, which caused frequent misclassifications of pixels around the periphery of large crop cover patch clusters and of pixels that form small, sparsely dispersed crop cover patches.

  7. Self-Assembly of Amphiphilic Block Copolypeptoids with C 2 -C 5 Side Chains in Aqueous Solution

    KAUST Repository

    Fetsch, Corinna; Flecks, Silvana; Gieseler, Dan; Marschelke, Claudia; Ulbricht, Juliane; van Pé e, Karl-Heinz; Luxenhofer, Robert

    2014-01-01

    © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Nowadays, amphiphilic molecules play an important role in our life. In medical applications, amphiphilic block copolymers have attracted much attention as excipients in drug delivery systems. Here

  8. In vitro and in vivo dependency of chemokine generation on C5a and TNF-alpha

    DEFF Research Database (Denmark)

    Czermak, B J; Sarma, V; Bless, N M

    1999-01-01

    production in vitro and in vivo. Two rat CXC chemokines (macrophage inflammatory protein (MIP)-2 and cytokine-induced neutrophil chemoattractant (CINC)) as well as three rat CC chemokines (MIP-1alpha, MIP-1beta, and monocyte chemoattractant protein (MCP)-1) were investigated. Chemokine generation in vitro...

  9. 'HoneySweet' (C5), the first genetically engineered Plum pox virus-resistant plum (Prunus domestica L.) cultivar

    Science.gov (United States)

    ‘HoneySweet’ plum was released by the U.S. Department of Agriculture, Agricultural Research Service, to provide U.S. growers and P. domestica plum breeders with a high fruit quality plum cultivar resistant to Plum pox virus (PPV). ‘HoneySweet’ was developed through genetic engineering utilizing the...

  10. Evaluation of the Flying Qualities Requirements of MIL-F-8785B (ASG) using the C-5A Airplane

    Science.gov (United States)

    1975-03-20

    sea level (MSL), ft h Maximum seivicu altitude, ftma• h1 M0ixmum op.rational altitude, fta max h Minimum operational altitude, ft ra.n H Total flight...0.04 2,000 675,00U Fmd 0.1161 0.029 0.04 The fla)s down data, li t: the i,,ise r-suIt-, sho., : oat the period (54 to 74 seconds) is easily contiallable

  11. Reversible Sigma C-C Bond Formation Between Phenanthroline Ligands Activated by (C5Me5)2Yb

    Energy Technology Data Exchange (ETDEWEB)

    Nocton, Gr& #233; gory; Lukens, Wayne W.; Booth, Corwin H.; Rozenel, Sergio S.; Medling, Scott A.; Maron, Laurent; Andersen, Richard A.

    2014-06-26

    The electronic structure and associated magnetic properties of the 1,10-phenanthroline adducts of Cp*2Yb are dramatically different from those of the 2,2?-bipyridine adducts. The monomeric phenanthroline adducts are ground state triplets that are based upon trivalent Yb(III), f13, and (phen ) that are only weakly exchange coupled, which is in contrast to the bipyridine adducts whose ground states are multiconfigurational, open-shell singlets in which ytterbium is intermediate valent ( J. Am. Chem. Soc 2009, 131, 6480; J. Am. Chem. Soc 2010, 132, 17537). The origin of these different physical properties is traced to the number and symmetry of the LUMO and LUMO+1 of the heterocyclic diimine ligands. The bipy has only one 1 orbital of b1 symmetry of accessible energy, but phen has two orbitals of b1 and a2 symmetry that are energetically accessible. The carbon p-orbitals have different nodal properties and coefficients and their energies, and therefore their populations change depending on the position and number of methyl substitutions on the ring. A chemical ramification of the change in electronic structure is that Cp 2Yb(phen) is a dimer when crystallized from toluene solution, but a monomer when sublimed at 180190 C. When 3,8-Me2phenanthroline is used, the adduct Cp*2Yb(3,8-Me2phen) exists in the solution in a dimer monomer equilibrium in which G is near zero. The adducts with 3-Me, 4-Me, 5-Me, 3,8-Me2, and 5,6-Me2-phenanthroline are isolated and characterized by solid state X-ray crystallography, magnetic susceptibility and LIII-edge XANES spectroscopy as a function of temperature and variable-temperature 1H NMR spectroscopy.

  12. [(11)C]5-HTP and microPET are not suitable for pharmacodynamic studies in the rodent brain

    NARCIS (Netherlands)

    Visser, Anniek K D; Ramakrishnan, Nisha K; Willemsen, Antoon T M; Di Gialleonardo, Valentina; de Vries, Erik F J; Kema, Ido P; Dierckx, Rudi A J O; van Waarde, Aren

    The PET tracer [C-11]5-hydroxytryptophan ([C-11]5-HTP), which is converted to [C-11]5-hydroxytryptamine ([C-11]5-HT) by aromatic amino acid decarboxylase (AADC), is thought to measure 5-HT synthesis rates. But can we measure these synthesis rates by kinetic modeling of [C-11]5-HTP in rat? Male rats

  13. Aero thermal test results obtained on the n. C 5 EL 4 Cluster in the atmospheric pressure cell

    International Nuclear Information System (INIS)

    Gasc, B.

    1964-01-01

    In the framework of thermal studies on the EL-4 cluster, the full-scale tests at atmospheric pressure are designed to permit measurement of local values of the wall temperature, of the velocity and of the temperature in the fluid. The experimental results, obtained with the help of an original measuring apparatus, make it possible to follow the changes in these values along the cluster and to predict in much detail the in-pile thermal behaviour. In particular it is shown that changes in the wall temperature along the cluster are greatly influenced by disruption of the flow caused by grids and supports. (author) [fr

  14. Genetic evidence that the degradation of para-cresol by Geobacter metallireducens is catalyzed by the periplasmic para-cresol methylhydroxylase

    DEFF Research Database (Denmark)

    Chaurasia, Akhilesh Kumar; Tremblay, Pier-Luc; Holmes, Dawn E.

    2015-01-01

    -CoA dehydrogenase (bbsG), an enzyme required for toluene degradation by G. metallireducens that is homologous to the p-hydroxybenzylsuccinyl-CoA dehydrogenase involved in p-cresol degradation by Desulfobacula toluolica Tol2 via fumarate addition, and the gene encoding the alpha prime subunit of PCMH (pcmI), were...... deleted to investigate the possibility of co-existing p-cresol degradation pathways in G. metallireducens. The absence of a functional PcmI protein completely inhibited p-cresol degradation, while deletion of the bbsG gene had little impact. These results further support the observation that G...

  15. Export of functional Streptomyces coelicolor alditol oxidase to the periplasm or cell surface of Escherichia coli and its application in whole-cell biocatalysis

    NARCIS (Netherlands)

    van Bloois, Edwin; Winter, Remko T.; Janssen, Dick B.; Fraaije, Marco W.

    Streptomyces coelicolor A3(2) alditol oxidase (AldO) is a soluble monomeric flavoprotein in which the flavin cofactor is covalently linked to the polypeptide chain. AldO displays high reactivity towards different polyols such as xylitol and sorbitol. These characteristics make AldO industrially

  16. Macropolyhedral boron-containing cluster chemistry. Cluster opening and B-frame rearrangement in the reaction of B16H20 with [{(IrCl2(eta(5)-C5Me5)}(2)]. Synchrotron X-ray structures of [(eta(5)-C5Me5)(2)Ir2B16H17Cl] and [(eta(5)-C5Me5)(2)Ir2B16H15Cl

    Czech Academy of Sciences Publication Activity Database

    Carr, MJ.; Perera, SD.; Jelínek, Tomáš; Kilner, C. A.; Clegg, W.; Štíbr, Bohumil; Kennedy, J.D.

    2006-01-01

    Roč. 44, - (2006), s. 5221-5224 ISSN 1477-9226 R&D Projects: GA AV ČR(CZ) IAA400320601; GA ČR GA203/05/2646 Grant - others:EPSRC(GB) J/56929; EPSRC(GB) GR/L/49505; EPSRC(GB) R/61949 Institutional research plan: CEZ:AV0Z40320502 Keywords : intercluster bonding intimagy * matallaborane clusters * crystal-structures Subject RIV: CA - Inorganic Chemistry Impact factor: 3.012, year: 2006

  17. DNA (Cytosine-C5) Methyltransferase Inhibition by Oligodeoxyribonucleotides Containing 2-(1H)-Pyrimidinone (Zebularine Aglycon) at the Enzymatic Target Site

    OpenAIRE

    van Bemmel, Dana M.; Brank, Adam S.; Eritja, Ramon; Marquez, Victor E.; Christman, Judith K.

    2009-01-01

    Aberrant cytosine methylation in promoter regions leads to gene silencing associated with cancer progression. A number of DNA methyltransferase inhibitors are known to reactivate silenced genes; including 5-azacytidine and 2-(1H)-pyrimidinone riboside (zebularine). Zebularine is a more stable, less cytotoxic inhibitor compared to 5-azacytidine. To determine the mechanistic basis for this difference, we carried out a detailed comparisons of the interaction between purified DNA methyltransferas...

  18. DMPD: Functions of anaphylatoxin C5a in rat liver: direct and indirect actions onnonparenchymal and parenchymal cells. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available nnonparenchymal and parenchymal cells. Schieferdecker HL, Schlaf G, Jungermann K, Gotze O. Int Immunopharmac...chymal cells. Authors Schieferdecker HL, Schlaf G, Jungermann K, Gotze O. Publication Int Immunopharmacol. 2

  19. Discovery of C5-C17 poly- and perfluoroalkyl substances in water by in-line SPE-HPLC-Orbitrap with in-source fragmentation flagging.

    Science.gov (United States)

    Liu, Yanna; Pereira, Alberto Dos Santos; Martin, Jonathan W

    2015-04-21

    The presence of unknown organofluorine compounds in environmental samples has prompted the development of nontargeted analytical methods capable of detecting new perfluoroalkyl and polyfluoroalkyl substances (PFASs). By combining high volume injection with high performance liquid chromatography (HPLC) and ultrahigh resolution Orbitrap mass spectrometry, a sensitive (0.003-0.2 ng F/mL for model mass-labeled PFASs) untargeted workflow was developed for discovery and characterization of novel PFASs in water. In the first step, up to 5 mL of water is injected to in-line solid phase extraction, chromatographed by HPLC, and detected by electrospray ionization with mass spectral acquisition in parallel modes cycling back and forth: (i) full scan with ultrahigh resolving power (RP = 120,000, mass accuracy ≤3 ppm), and (ii) in-source fragmentation flagging scans designed to yield marker fragment ions including [C2F5](-) (m/z 118.992), [C3F7](-) (m/z 168.988), [SO4H](-) (m/z 96.959), and [Cl](-) (m/z 34.9). For flagged PFASs, plausible empirical formulas were generated from accurate masses, isotopic patterns, and fragment ions. In the second step, another injection is made to collect high resolution MS/MS spectra of suspect PFAS ions, allowing further confirmation of empirical formulas while also enabling preliminary structural characterization. The method was validated by applying it to an industrial wastewater, and 36 new PFASs were discovered. Of these, 26 were confidently assigned to 3 new PFAS classes that have not previously been reported in the environment: polyfluorinated sulfates (CnFn+3Hn-2SO4(-); n = 5, 7, 9, 11, 13, and 15), chlorine substituted perfluorocarboxylates (ClCnF2nCO2(-); n = 4-11), and hydro substituted perfluorocarboxylates (HCnF2nCO2(-); n = 5-16). Application of the technique to environmental water samples is now warranted.

  20. A Heterobimetallic Complex With an Unsupported Uranium(III)-Aluminum(I) Bond: (CpSiMe3)3U-AlCp* (Cp* = C5Me5)

    Energy Technology Data Exchange (ETDEWEB)

    Minasian, Stefan; Krinsky Ph.D., Jamin; Williams, Valerie; Arnold Ph.D., John

    2008-07-23

    The discovery of molecular metal-metal bonds has been of fundamental importance to the understanding of chemical bonding. For the actinides, examples of unsupported metal-metal bonds are relatively uncommon, consisting of Cp{sub 3}U-SnPh{sub 3}, and several actinide-transition metal complexes. Traditionally, bonding in the f-elements has been described as electrostatic; however, elucidating the degree of covalency is a subject of recent research. In carbon monoxide complexes of the trivalent uranium metallocenes, decreased {nu}{sub CO} values relative to free CO suggest that the U(III) atom acts as a {pi}-donor. Ephritikhine and coworkers have demonstrated that {pi}-accepting ligands can differentiate trivalent lanthanide and actinide ions, an effect that renders this chemistry of interest in the context of nuclear waste separation technology.

  1. Validation of MIL-F-9490D. General Specification for Flight Control System for Piloted Military Aircraft. Volume III. C-5A Heavy Logistics Transport Validation

    Science.gov (United States)

    1977-04-01

    subjected to extreme environmental climatic tests, including the IdL,-T-5289 test requirement. 5.1.9.2 Invulnerability to Lightning Strikes and Static...specified in Paragraph 3.2.3.2.1. The hydi aulic computing elements were designed to the requirements of MIL-C- 5503 and �-H-8775. I 297 L...and climate in any area of the world using MI,- STD-210, FAA-T3O-(49C, and MIL-F-9490, as applicable. Environmental areas included solar radiation

  2. PACE. A Program for Acquiring Competence in Entrepreneurship. Part III: Being an Entrepreneur. Unit E: Successful Selling. Research and Development Series No. 194 C-5.

    Science.gov (United States)

    Ohio State Univ., Columbus. National Center for Research in Vocational Education.

    This three-part curriculum for entrepreneurship education is primarily for postsecondary level, including four-year colleges and adult education, but it can be adapted for special groups or vocational teacher education. The emphasis of the eight instructional units in Part III is operating a business. Unit E focuses on personal (face-to-face)…

  3. Reaction of tricyclopentadienyl uranium chloride (C5H5)3UCl with triethylaluminium Al(C2H5)3

    International Nuclear Information System (INIS)

    Vasil'ev, V.K.; Sokolov, V.N.; Kondratenkov, G.P.

    1977-01-01

    The mechanism of reaction of tricyclopentadienyluranchloride with triethylaluminium was studied by the NMR 1 method. The kinetic and thermodynamic parameters of this reaction (k=(6+-1)x10 5 sec -1 , E=27+-4 kJ/molxK) were estimated from the temperature dependence of the chemical shifts with due regard for the paramagnetic shift and the half-width of the averaged-signal line

  4. Combustion, gaseous and particulate emission of a diesel engine fueled with n-pentanol (C5 alcohol) blended with waste cooking oil biodiesel

    International Nuclear Information System (INIS)

    Zhu, Lei; Xiao, Yao; Cheung, C.S.; Guan, Chun; Huang, Zhen

    2016-01-01

    Highlights: • BP blends have fast combustion process at high temperature. • BP blends improve brake thermal efficiency of biodiesel. • Particle mass and number concentration could be reduced by pentanol addition. • Diameter of the primary particle is minimized by pentanol addition. • The addition of 10% pentanol is recommended as a suitable replacement ratio. - Abstract: The combustion, gaseous and particulate emissions of a diesel engine fueled with biodiesel–pentanol (BP) blends were investigated under different engine loads. The results indicate that with the increased pentanol fraction, the start of combustion is delayed. All of the BP blends provide faster combustion than biodiesel and diesel fuel from CA10 to CA90. The faster combustion of BP blends leads to a higher BTE than that of biodiesel and diesel fuel in most cases. The particle mass and number concentrations are reduced by the addition of pentanol in biodiesel in most test conditions, due to the higher oxygen concentration for the fuel/air stoichiometry, longer ignition delay for fuel/air mixing, and lower viscosity for the improvement of atomization. The R−(C=O)O−R′ group in biodiesel is less efficient in suppressing the soot precursor’s formation than the R−OH group in pentanol. The diameter of the primary particles is reduced with the increased addition of pentanol. The particulate emission of BP10 have higher oxidation reactivity that that of BP20 and BP30. Base on this study, pentanol–biodiesel can be considered as an acceptable alternative fuel for diesel engines due to its improved combustion performance and reduced particulate emissions.

  5. Molecular Interactions in Binary Mixtures of Benzene with 1-Alkanols(C5,C7,C8) at 35℃:An Ultrasonic Study

    Institute of Scientific and Technical Information of China (English)

    ALI,A.; IBRAHIM.M; 等

    2003-01-01

    Densities and ultrasonic speeds have been measured in binary mixtures of benzene with 1-pentanol,1-heptanol and 1-octanol,and in the pure components,as a function of compostion at 35℃.The isentropic compressibility,intermolecular free length,relative association,acoustic impedance,isothermal compressibility,thermal expansion coefficient,deviations in isentropic compressibility,excess freee length,excess volume,deviations in ultrasonic speed,excess acoustic impedance,apparent molar compressibility,apparent molar volume,partial molar volume of 1-alkanol in benzene have been calculated from the experimental data of densities and ultrasonic speeds.The variation of these parameters with composition indicates weak interaction between the component molecules and this interaction decreases in the order:1-pentanol>1-heptanol>1-octanol.Further,theoretical values of ultrasonic speeds were evaluated using free length theory,collision factor theory,Nomoto's relation and Van Dael-Vangeel ideal mixing relation.The relative merits of these theories and relations were discussed for these systems.

  6. Environmental Assessment of the 445th Airlift Wing Conversion from C-5 to C-17 Aircraft at Wright-Patterson Air Force Base

    Science.gov (United States)

    2010-12-01

    prefabricated clean room with a 15-foot ceiling . Additional renovation requirements for this shop area 22 include providing a self-contained heating...construction and demolition debris. Recycling programs for various 21 waste categories (e.g., glass , metals, and papers) reduce reliance on landfills...from Defense Fuel Support Point – Lebanon . The 21 Bulk Fuels Storage tank farm is comprised of ten 420,000-gallon JP-8 ASTs and one 840,000-gallon JP

  7. Readily-accessible oxidation of d0 organozirconium compounds: The electronic structure of (η5-C5H5)3ZrX compounds

    International Nuclear Information System (INIS)

    Strittmatter, R.J.; Bursten, B.E.; Rhodes, L.F.; Morris, D.E.; Rogers, R.D.

    1990-01-01

    In an effort to obtain a comparison between organotransition metal and organoactinide complexes, a series of Cp 3 ZrX compounds have been synthesized. A single crystal X-ray crystallographic study of Cp 3 ZrCl reveals that all three Cp ligands are bound in an η 5 fashion. Electrochemical investigations of this series show a first oxidation of these d 0 compounds approximately one volt less positive than the d 0 Cp 2 ZrX 2 compounds and approximately one-half volt less positive than the d 0 f 0 Cp 3 ThCl compound. These results will be presented along with a discussion of the electronic structure of this series, as determined by Xα-SW and Fenske-Hall calculations

  8. Catalytic Oligomerization of Terminal Alkynes by Lanthanide Carbyls (η5-C5Me5)2LnCH(SiMe3)2 (Ln = Y, La, Ce)

    NARCIS (Netherlands)

    Heeres, H.J.; Teuben, J.H.

    1991-01-01

    Lanthanide and group 3 carbyls Cp*2LnCH(SiMe3)2 (1, Ln = Y; 2, Ln = La; 3, Ln = Ce) are active catalyst precursors for the oligomerization of terminal alkynes HC≡CR (R = alkyl, aryl, SiMe3). The regioselectivity and the extent of oligomerization depend strongly on the lanthanide applied as well as

  9. Synthesis of C3, C5, and C7 pregnane derivatives and their effect on NMDA receptor responses in cultured rat hippocampal neurons

    Czech Academy of Sciences Publication Activity Database

    Šťastná, Eva; Chodounská, Hana; Pouzar, Vladimír; Kapras, Vojtěch; Borovská, Jiřina; Cais, Ondřej; Vyklický ml., Ladislav

    2009-01-01

    Roč. 74, č. 2 (2009), s. 256-263 ISSN 0039-128X R&D Projects: GA ČR(CZ) GA309/07/0271; GA ČR(CZ) GA203/08/1498 Grant - others:GA MŠk(CZ) LC554; FP6 Photolysis(XE) LSHM-CT-2007-037765 Program:LC Institutional research plan: CEZ:AV0Z40550506; CEZ:AV0Z50110509 Keywords : pregnane derivatives * NMDA receptor * structure-activity relationship * patch-clamp recording Subject RIV: CC - Organic Chemistry Impact factor: 2.905, year: 2009

  10. Isomerization of C5–C7 paraffins over a Pt/WO3–ZrO2 catalyst using industrial feedstock

    Czech Academy of Sciences Publication Activity Database

    Hidalgo, J. M.; Kaucký, Dalibor; Bortnovsky, O.; Černý, R.; Sobalík, Zdeněk

    2014-01-01

    Roč. 145, č. 9 (2014), s. 1407-1416 ISSN 0026-9247 R&D Projects: GA MPO FR-TI3/316 Institutional support: RVO:61388955 Keywords : isomers * alkanes * hydrocarbons Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.222, year: 2014

  11. Stellar and Planetary Parameters for K2 's Late-type Dwarf Systems from C1 to C5

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, Arturo O. [Department of Astronomy, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182 (United States); Crossfield, Ian J. M.; Peacock, Sarah [Lunar and Planetary Laboratory, University of Arizona, 1629 E. University Blvd, Tucson, AZ 85721 (United States); Schlieder, Joshua E. [NASA Ames Research Center, Moffett Field, CA 94035 (United States); Dressing, Courtney D. [Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125 (United States); Obermeier, Christian [Max Planck Institut für Astronomie, Heidelberg (Germany); Livingston, John; Petigura, Erik A. [Department of Astronomy, Graduate School of Science, The University of Tokyo, 7-3-1 Bunkyo-ku, Tokyo 113-0033 (Japan); Ciceri, Simona [Department of Astronomy, Stockholm University, SE-106 91 Stockholm (Sweden); Beichman, Charles A. [NASA Exoplanet Science Institute, California Institute of Technology, Pasadena, CA 91125 (United States); Lépine, Sébastien [Department of Physics and Astronomy, Georgia State University, 25 Park Pl NE #605, Atlanta, GA 30303 (United States); Aller, Kimberly M. [Institute for Astronomy, University of Hawai’i at Mānoa, 2680 Woodlawn Dr., Honolulu, HI 96822 (United States); Chance, Quadry A. [Steward Observatory, University of Arizona, 933 N. Cherry Ave, Tucson, AZ 85719 (United States); Howard, Andrew W. [Department of Astronomy, California Institute of Technology, Pasadena, CA 91125 (United States); Werner, Michael W. [Jet Propulsion Laboratory, 4800 Oak Grove Dr., Pasadena, CA 91109 (United States)

    2017-03-01

    The NASA K2 mission uses photometry to find planets transiting stars of various types. M dwarfs are of high interest since they host more short-period planets than any other type of main-sequence star and transiting planets around M dwarfs have deeper transits compared to other main-sequence stars. In this paper, we present stellar parameters from K and M dwarfs hosting transiting planet candidates discovered by our team. Using the SOFI spectrograph on the European Southern Observatory’s New Technology Telescope, we obtained R ≈ 1000 J -, H -, and K -band (0.95–2.52 μ m) spectra of 34 late-type K2 planet and candidate planet host systems and 12 bright K4–M5 dwarfs with interferometrically measured radii and effective temperatures. Out of our 34 late-type K2 targets, we identify 27 of these stars as M dwarfs. We measure equivalent widths of spectral features, derive calibration relations using stars with interferometric measurements, and estimate stellar radii, effective temperatures, masses, and luminosities for the K2 planet hosts. Our calibrations provide radii and temperatures with median uncertainties of 0.059 R {sub ⊙} (16.09%) and 160 K (4.33%), respectively. We then reassess the radii and equilibrium temperatures of known and candidate planets based on our spectroscopically derived stellar parameters. Since a planet’s radius and equilibrium temperature depend on the parameters of its host star, our study provides more precise planetary parameters for planets and candidates orbiting late-type stars observed with K2 . We find a median planet radius and an equilibrium temperature of approximately 3 R {sub ⊕} and 500 K, respectively, with several systems (K2-18b and K2-72e) receiving near-Earth-like levels of incident irradiation.

  12. Single Stage Tandem Mass Spectrometry Assignment of the C-5 Uronic Acid Stereochemistry in Heparan Sulfate Tetrasaccharides using Electron Detachment Dissociation

    NARCIS (Netherlands)

    Agyekum, Isaac; Zong, Chengli; Boons, Geert-Jan; Amster, I. Jonathan

    The analysis of heparan sulfate (HS) glycosaminoglycans presents many challenges, due to the high degree of structural heterogeneity arising from their non-template biosynthesis. Complete structural elucidation of glycosaminoglycans necessitates the unambiguous assignments of sulfo modifications and

  13. Liquid Phase Behaviour in Systems of 1-Butyl-3-Alkylimidazolium bis(trifluoromethyl)SulfonylimideIonic Liquids with Water: Influence of the Structure of the C5 Alkyl Substituent.

    Czech Academy of Sciences Publication Activity Database

    Rotrekl, Jan; Storch, Jan; Velíšek, Petr; Schröer, W.; Jacquemin, J.; Wagner, Zdeněk; Husson, P.; Bendová, Magdalena

    2017-01-01

    Roč. 46, č. 7 (2017), s. 1456-1474 ISSN 0095-9782 R&D Projects: GA MŠk LD14090 Institutional support: RVO:67985858 Keywords : ionic liquids * liquid phase behaviour * ising model Subject RIV: CF - Physical ; Theoretical Chemistry OBOR OECD: Physical chemistry Impact factor: 1.342, year: 2016

  14. Case report: 122° kyphosis secondary to C5-L3 laminectomy and quadriplegia, surgical correction and 30-year follow-up.

    Science.gov (United States)

    Winter, R B; Akbarnia, B A

    2011-09-01

    The study design was a case report with 30-year follow-up. In 1980, there were no pedicle screws available, so it was a great challenge to achieve correction and fusion in a patient with no laminae, and who was quadriplegic. Such a case with such a long follow-up has not been previously reported. This is a single case report with an ultra-long follow-up. The patient underwent an anterior fusion from T3 to L4 via two incisions, and at a second stage, a posterior fusion from T3 to S1 using Luque rods and wires passed through the foramenae. After 2 years he underwent repair of two pseudarthroses with both anterior and posterior procedures. He achieved solid fusion following the pseudarthrosis repair. Although being a C7 quadriplegic all his life, he is totally independent in his activities of daily living, and is fully employed. Correction and fusion can be achieved even in the absence of laminae and pedicle screws.

  15. Dynamic Response of Control Servo System Installed in NAES-Equipped SB2C-5 Airplane (BuAer No. 83135)

    Science.gov (United States)

    Smaus, Louis H.; Stewart, Elwood C.

    1950-01-01

    Dynamic--response measurements for various conditions of displacement and rate signal input, sensitivity setting, and simulated hinge moment were made of the three control-surface servo systems of an NAES-equipped remote-controlled airplane while on the ground. The basic components of the servo systems are those of the General Electric Company type G-1 autopilot using electrical signal. sources, solenoid-operated valves, and hydraulic pistons. The test procedures and difficulties are discussed, Both frequency and transient-response data, are presented and comparisons are made. The constants describing the servo system, the undamped natural frequency, and the damping ratio, are determined by several methods. The response of the system with the addition of airframe rate signal is calculated. The transfer function of the elevator surface, linkage, and cable system is obtained. The agreement between various methods of measurement and calculation is considered very good. The data are complete enough and in such form that they may be used directly with the frequency-response data of an airplane to predict the stability of the autopilot-airplane combination.

  16. ORF Alignment: NC_004337 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available ... CFT073] ref|NP_415411.1| periplasmic chaperone effects ... translocation... ... periplasmic protein effects translocation of ... lipoproteins from inner membrane to outer; pe...riplasmic ... chaperone effects translocation of lipoproteins from ... ...78.1| periplasmic protein effects translocation ... of lipoproteins from i...nner membrane to outer ... [Escherichia coli O157:H7 EDL933] dbj|BAB34399.1| ... periplasmic protein effects

  17. ORF Alignment: NC_004741 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available ... CFT073] ref|NP_415411.1| periplasmic chaperone effects ... translocation... ... periplasmic protein effects translocation of ... lipoproteins from inner membrane to outer; pe...riplasmic ... chaperone effects translocation of lipoproteins from ... ...78.1| periplasmic protein effects translocation ... of lipoproteins from i...nner membrane to outer ... [Escherichia coli O157:H7 EDL933] dbj|BAB34399.1| ... periplasmic protein effects

  18. ORF Alignment: NC_002655 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available ... CFT073] ref|NP_415411.1| periplasmic chaperone effects ... translocation... ... periplasmic protein effects translocation of ... lipoproteins from inner membrane to outer; pe...riplasmic ... chaperone effects translocation of lipoproteins from ... ...78.1| periplasmic protein effects translocation ... of lipoproteins from i...nner membrane to outer ... [Escherichia coli O157:H7 EDL933] dbj|BAB34399.1| ... periplasmic protein effects

  19. ORF Alignment: NC_002695 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available ... CFT073] ref|NP_415411.1| periplasmic chaperone effects ... translocation... ... periplasmic protein effects translocation of ... lipoproteins from inner membrane to outer; pe...riplasmic ... chaperone effects translocation of lipoproteins from ... ...78.1| periplasmic protein effects translocation ... of lipoproteins from i...nner membrane to outer ... [Escherichia coli O157:H7 EDL933] dbj|BAB34399.1| ... periplasmic protein effects

  20. ORF Alignment: NC_000913 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available ... CFT073] ref|NP_415411.1| periplasmic chaperone effects ... translocation... ... periplasmic protein effects translocation of ... lipoproteins from inner membrane to outer; pe...riplasmic ... chaperone effects translocation of lipoproteins from ... ...78.1| periplasmic protein effects translocation ... of lipoproteins from i...nner membrane to outer ... [Escherichia coli O157:H7 EDL933] dbj|BAB34399.1| ... periplasmic protein effects

  1. ORF Alignment: NC_004431 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available ... CFT073] ref|NP_415411.1| periplasmic chaperone effects ... translocation... ... periplasmic protein effects translocation of ... lipoproteins from inner membrane to outer; pe...riplasmic ... chaperone effects translocation of lipoproteins from ... ...78.1| periplasmic protein effects translocation ... of lipoproteins from i...nner membrane to outer ... [Escherichia coli O157:H7 EDL933] dbj|BAB34399.1| ... periplasmic protein effects

  2. Fiscal 2000 report on geothermal energy development promotion survey. Phase 1. Report on environmental impact survey in No. C-5 Appi district (Weather); 2000 nendo chinetsu kaihatsu sokushin chosa hokokusho. No.C-5. Appi chiiki - kankyo eikyo chosa (kisho) dai 1 ji

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    For grasping the characteristics of weather, climate, and natural earthquakes in and around the geothermal survey area in the Appi district, Iwate Prefecture, observation data of weather stations or the like in the neighborhood were collected and put in an easy-to-use order. Weather and earthquake data of the 1990-1999 decade were collected and subjected to statistical processing. Weather in the Appi District Survey C area is characterized in that it assumes the Japan Sea side pattern with much snow in winter and much rain in the rainy season. In the other seasons, however, it assumes the Pacific side inland pattern. Weather data in the Appi district and its vicinity are deemed to be similar to the values observed at the Hachimantai weather station. The area covered by the survey, however, is higher than the Hachimantai weather station by 400-900m, and therefore is that much colder and has more rain and snow. As for earthquakes, a total of 647 were recorded in the decade 1990-1999. In the Appi District Survey C area, which is approximately 20km times 20km large, suffered 31.1 events/month in 1998, which indicated a great rise in seismic occurrence. The rise is now attributed to the volcanic activity of Mt. Iwate which is deemed to be waning. (NEDO)

  3. Comparison of the one-electron oxidations of CO-bridged vs unbridged bimetallic complexes: Electron-transfer chemistry of Os2Cp2(CO)4 and Os2Cp∗2(μ-CO)2(CO)2 (Cp = η5-C5H5, Cp∗ = η5-C5Me5)

    KAUST Repository

    Laws, Derek R.; Bullock, Morris Morris; Lee, Richmond; Huang, Kuo-Wei; Geiger, William E.

    2014-01-01

    with an approximately 1:1 mixture of anti and gauche structures for the 33 e- radical cation in which it has retained all-terminal bonding of the CO ligands. Density functional theory (DFT) calculations, including orbital-occupancy-perturbed Mayer bond-order analyses

  4. Chemistry of phosphido-bridged dimolybdenum complexes. Part 2: the reaction of [(η-C5H5)2Mo2(μ-H)(μ-PMe2) (CO)4] with alkynes: X-ray crystal structure of [(η-C5H5)2Mo2 (μ-σ:η2-C(Me) = CHMe) (μ-PMe2) (CO)3

    International Nuclear Information System (INIS)

    Conole, G.; Henrick, K.; McPartlin, M.; Horton, A.D.; Mays, M.J.

    1988-01-01

    The photolytic reactions with alkynes have been studied. With MeC ≡ CMe the major product is the μ-vinyl complex which has been characterised by a single crystal X-ray diffraction study. This shows that the methyl groups on the μ-vinyl ligand adopt a mutually trans orientation; the Mo - Mo bond length is 3.056 (1) A (mean for two independent molecules). The unsymmetrical alkynes give inseparable isomeric mixtures but HC ≡ CH and PhC ≡ CPh do not give simple μ-vinyl products. Each of the above μ-vinyl complexes is accompanied by a minor yield of the corresponding oxo complex and a low yield of such a complex is also obtained in the reaction with acetylene itself. 21 refs

  5. Fiscal 2000 report on geothermal energy development promotion survey. Phase 1. Report on environmental impact survey in No. C-5 Appi district (Hot spa fluctuation); 2000 nendo chinetsu kaihatsu sokushin chosa hokokusho. No. C-5. Appi chiiki kankyo chosa (onsen hendo) dai 1 ji

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    For the assessment of the environmental impact to be produced by geothermal exploration well boring and short-term outburst tests, water in hot spas, fountains, and rivers in and around the Appi survey district was inspected for fluctuation. A survey was conducted of multiple components to help analysis of the geothermal reservoir structure. Distributed in the alteration zone in this district are the hot spas of Kusanoyu, Shin-Kusanoyu, Appi, and so forth, and, in the vicinity, numerous hot spas including Iwahatanoyu belonging to the Appi hot spa. In the multiple component survey, 12 hot spas, 1 fountain, 8 rivers, and 2 gas wells were subjected to measurement. In the fluctuation survey, 5 hot spas, 1 fountain, 5 rivers, and the amount of precipitation were subjected to measurement. In the survey of river bottom quality and river bed rocks, river bottom quality was checked at 18 spots and river bed rocks at 12 spots. It was found that fluctuation was great in the amount of welling water at Kusanoyu, Shin-kusanoyu, and Appi, with the coefficient of fluctuation recording 10 or more. A negative correlation was detected between the welling amount and water temperature. It is deemed that the hot water spurts out of natural fountains or shallow wells and that its temperature tends to grow lower with an increase in meteoric water by which it is diluted. (NEDO)

  6. Prospective Evaluation of Transcatheter Arterial Chemoembolization (TACE) with Multiple Anti-Cancer Drugs (Epirubicin, Cisplatin, Mitomycin C, 5-Fluorouracil) Compared with TACE with Epirubicin for Treatment of Hepatocellular Carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Sahara, Shinya; Kawai, Nobuyuki; Sato, Morio, E-mail: morisato@mail.wakayama-med.ac.jp; Tanaka, Takami; Ikoma, Akira; Nakata, Kouhei; Sanda, Hiroki; Minamiguchi, Hiroki; Nakai, Motoki; Shirai, Shintaro; Sonomura, Tetsuo [Wakayama Medical University, Department of Radiology (Japan)

    2012-12-15

    Purpose: To compare the efficacy of transcatheter arterial chemoembolization (TACE) using multiple anticancer drugs (epirubicin, cisplatin, mitomycin C, and 5-furuorouracil: Multi group) with TACE using epirubicin (EP group) for hepatocellular carcinoma (HCC). Materials and Methods: The study design was a single-center, prospective, randomized controlled trial. Patients with unrespectable HCC confined to the liver, unsuitable for radiofrequency ablation, were assigned to the Multi group or the EP group. We assessed radiographic response as the primary endpoint; secondary endpoints were progression-free survival (PFS), safety, and hepatic branch artery abnormality (Grade I, no damage or mild vessel wall irregularity; Grade II, overt stenosis; Grade III, occlusion; Grades II and III indicated significant hepatic artery damage). A total of 51 patients were enrolled: 24 in the Multi group vs. 27 in the EP group. Results: No significant difference in HCC patient background was found between the groups. Radiographic response, PFS, and 1- and 2-year overall survival of the Multi vs. EP group were 54% vs. 48%, 6.1 months vs. 8.7 months, and 95% and 65% vs. 85% and 76%, respectively, with no significant difference. Significantly greater Grade 3 transaminase elevation was found in the Multi group (p = 0.023). Hepatic artery abnormality was observed in 34% of the Multi group and in 17.1% of the EP group (p = 0.019). Conclusion: TACE with multiple anti-cancer drugs was tolerable but appeared not to contribute to an increase in radiographic response or PFS, and caused significantly more hepatic arterial abnormalities compared with TACE with epirubicin alone.

  7. Excess molar volumes and dynamic viscosities for binary mixtures of toluene + n-alkanes (C5-C10) at T = 298.15 K - Comparison with Prigogine-Flory-Patterson theory

    International Nuclear Information System (INIS)

    Iloukhani, Hossein; Rezaei-Sameti, Mahdi; Basiri-Parsa, Jalal

    2006-01-01

    Densities ρ, dynamic viscosities η, for binary mixtures of toluene with some n-alkanes, namely, n-pentane, n-hexane, n-heptane, n-octane, n-nonane, and n-decane have been measured over the complete composition range. Excess molar volumes V E , viscosity deviations Δη, and excess Gibbs free energy of activation ΔG * E , were calculated there from and were correlated by Redlich-Kister type function in terms of mole fractions. For mixtures of toluene with n-pentane and n-hexane the V E is negative and for the remaining systems is positive. The Δη values are negative for all the studied mixtures. The ΔG * E values shows the positive values for the binary mixtures with n-decane, whereas the negative values have been observed for all the remaining binary mixtures. From the results, the excess thermal expansivities at constant pressure α E , is also estimated. The Prigogine-Flory-Patterson (PFP) theory and its applicability in predicting V E is tested. The results obtained for viscosity of binary mixtures were used to test the semi-empirical relations of Grunberg and Nissan, Tamura and Kurata, Hind et al., Katti and Chaudhri, McAllister, Heric, Kendall, and Monroe. The experimental on the constituted binaries are analyzed to discus the nature and strength of intermolecular interactions in these mixtures

  8. Unravelling the pH-dependence of a molecular photocatalytic system for hydrogen production† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c5sc01349f Click here for additional data file.

    Science.gov (United States)

    Pastor, Ernest; Gross, Manuela A.; Selim, Shababa

    2015-01-01

    Photocatalytic systems for the reduction of aqueous protons are strongly pH-dependent, but the origin of this dependency is still not fully understood. We have studied the effect of different degrees of acidity on the electron transfer dynamics and catalysis taking place in a homogeneous photocatalytic system composed of a phosphonated ruthenium tris(bipyridine) dye (RuP) and a nickel bis(diphosphine) electrocatalyst (NiP) in an aqueous ascorbic acid solution. Our approach is based on transient absorption spectroscopy studies of the efficiency of photo-reduction of RuP and NiP correlated with pH-dependent photocatalytic H2 production and the degree of catalyst protonation. The influence of these factors results in an observed optimum photoactivity at pH 4.5 for the RuP–NiP system. The electron transfer from photo-reduced RuP to NiP is efficient and independent of the pH value of the medium. At pH RuP photo-reduction by the sacrificial electron donor, ascorbic acid. At pH >4.5, the efficiency of the system is limited by the poor protonation of NiP, which inhibits its ability to reduce protons to hydrogen. We have therefore developed a rational strategy utilising transient absorption spectroscopy combined with bulk pH titration, electrocatalytic and photocatalytic experiments to disentangle the complex pH-dependent activity of the homogenous RuP–NiP photocatalytic system, which can be widely applied to other photocatalytic systems. PMID:28717491

  9. Reduction-Induced Cyclization and Redox Reactions of Fully Methylated Titanocene Dichlorides Bearing Pendant Alkenyldimethylsilyl Groups, [TiCl2{.eta.5-C5Me4(SiMe2R)}2] (R=Vinyl, and Allyl)

    Czech Academy of Sciences Publication Activity Database

    Lukešová, Lenka; Štěpnička, P.; Fejfarová, K.; Gyepes, R.; Císařová, I.; Horáček, Michal; Kubišta, Jiří; Mach, Karel

    2002-01-01

    Roč. 21, - (2002), s. 2639-2653 ISSN 0276-7333 R&D Projects: GA AV ČR IAA4040004; GA ČR GA203/02/0436 Institutional research plan: CEZ:AV0Z4040901 Keywords : titanocene * reduction-induced * dichlorides Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.215, year: 2002

  10. Tetranuclear Complexes of [Fe(CO)2(C5H5)]+ with the TCNX Ligands (TCNX = TCNE, TCNQ, TCNB): Evidence for an Intramolecular Electron Transfer Dichotomy in Compounds (.mu.4-TCNX)[MLn]4

    Czech Academy of Sciences Publication Activity Database

    Maity, A. N.; Schwederski, B.; Sarkar, B.; Záliš, Stanislav; Fiedler, Jan; Kar, S.; Lahiri, G. K.; Duboc, C.; Grunert, M.; Gütlich, P.; Kaim, W.

    2007-01-01

    Roč. 46, č. 18 (2007), s. 7312-7320 ISSN 0020-1669 R&D Projects: GA MŠk 1P05OC068; GA AV ČR 1ET400400413 Institutional research plan: CEZ:AV0Z40400503 Keywords : TCNX ligands * tetracyanoethene * intramolecular electron transfer Subject RIV: CG - Electrochemistry Impact factor: 4.123, year: 2007

  11. Configuration-dependent conformational transmission in trigonal-bipyramidal phosphorus(V) compounds. Enhanced gauche (-) population around the C(5)-C(6) linkage in 6-phosphorus(V) phosphorylated tetramethyl-a-D-galactopyranoside

    NARCIS (Netherlands)

    Vries, de N.K.; Buck, H.M.

    1986-01-01

    A 300-MHz 1H NMR variable-temperature study of the 1'-phosphorylated trigonal-bipyramidal (TBP) tetrahydropyran-2-methyl model compound 4 is reported. For this compound, in which both the equatorial and axial sites undergoing phosphorus pseudorotation bear a tetrahydro-pyran-2-methyl group, a

  12. Diferratricarbaboranes of the subcloso-[eta(5)-C5H5)(2)Fe2C3B8H11] type, the first representatives of the 13-vertex dimetallatricarbaborane series

    Czech Academy of Sciences Publication Activity Database

    Grüner, Bohumír; Štíbr, Bohumil; Kivekäs, R.; Sillanpää, R.; Stopka, Pavel; Teixidor, F.; Vinas, C.

    2003-01-01

    Roč. 9, č. 24 (2003), s. 6115-6121 ISSN 0947-6539 R&D Projects: GA MŠk LN00A028; GA ČR GA203/00/1042; GA ČR GA203/01/0944 Institutional research plan: CEZ:AV0Z4032918 Keywords : boranes * carboranes * cluster compounds Subject RIV: CA - Inorganic Chemistry Impact factor: 4.353, year: 2003

  13. Two New 1,1,3,3-Tetramethylguanidinium Halochromates (C5H14N3CrO3X (X: Cl, F: Efficient Reagents for Oxidation of Organic Substrates under Solvent-Free Conditions and Microwave Irradiation

    Directory of Open Access Journals (Sweden)

    Kıvılcım Şendıl

    2016-01-01

    Full Text Available Two new mild oxidizing agents 1,1,3,3-tetramethylguanidinium fluorochromate (TMGFC and 1,1,3,3-tetramethylguanidinium chlorochromate (TMGCC were prepared in high yields by reacting tetramethylguanidine with CrO3 and related acid. These reagents are suitable to oxidize various primary and secondary alcohols and oximes to the corresponding carbonyl compounds under solvent-free conditions and microwave irradiation.

  14. Highly Functionalised Cyclopentanes by Radical Cyclisation of Unsaturated Bromolactones III. Preparation of Carbaaldohexofuranoses. - Determination of the Relative Configuration at C-4/C-5 of 2,3-Unsaturated heptono-1,4-lactones by Means of 1-H NMR Spectroscopy

    DEFF Research Database (Denmark)

    Lundt, Inge; Horneman, Anne Marie

    1999-01-01

    Two new carbaaldohexofuranoses, carba--D-glucofuranose and carba--L-mannofuranose have been prepared using 5,6-O-isopropylidene-D-glycero-L-galacto-heptono-1,4-lactone (6) as the starting material. The key step was a highly stereoselective intramolecular 5-exo-trig radical cyclisation of C-2......-substituted 2,3-unsaturated 7-bromo-7-deoxy-heptono-1,4-lactones promoted by tributyltin hydride. Assignment of the configuration of the unsaturated lactones was based upon NMR data of related compounds. The starting material, compound 6, was obtained by chain elongation of D-gulose, and a facile method...

  15. Reduced and Excited States of the Intermediates (α-diimine)(C5R5) Rh in Hydride Transfer Catalysis Schemes: EPR and Resonance Raman Spectroscopy, and Comparative DFT Calculations of Co, Rh and Ir Analoques

    Czech Academy of Sciences Publication Activity Database

    Sieger, M.; Kaim, W.; Stufkens, D. J.; Snoeck, T. L.; Stoll, H.; Záliš, Stanislav

    -, č. 22 (2004), s. 3815-3821 ISSN 1477-9226 R&D Projects: GA AV ČR 1ET400400413 Institutional research plan: CEZ:AV0Z4040901 Keywords : gas shift reaction * cationic iridium (III) complexes * electrochemical properties Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.926, year: 2004

  16. Die kunjugative Verbrückung metallorganischer Reaktionszentren Heterozweikernkomplexen [(OC)3ClRe(.mu.-L)MCl(C5Me5)]+, M=Rh oder Ir Spektroskopische Konsequenzen reduktiver Aktivierung

    Czech Academy of Sciences Publication Activity Database

    Kaim, W.; Scheiring, T.; Weber, M.; Fiedler, Jan

    2004-01-01

    Roč. 630, - (2004), s. 1883-1893 ISSN 0044-2313 R&D Projects: GA MŠk OC D15.10; GA MŠk OC D14.20 Institutional research plan: CEZ:AV0Z4040901 Keywords : electrochemistry * iridium * rhenium Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.086, year: 2004

  17. Influence of the Torsion Angle in 3,3'-Dimethyl-2,2'-bipyridine on the Intermediate Valence of Yb in (C5Me5)2 Yb(3,3'-Me2-bipy)

    Energy Technology Data Exchange (ETDEWEB)

    Nocton, Gr& #233; gory; Booth, Corwin H.; Maron, Laurent; Andersen, Richard A.

    2014-06-26

    The synthesis and X-ray crystal structures of Cp-2*Yb(3,3'-Me(2)bipy) and [Cp-2 Yb(3,3'-Me(2)bipy)][Cp-2 YbCl1.6I0.4]center dot CH2Cl2 are described. In both complexes, the NCCN torsion angles are approximately 40 degrees. The temperature-independent value of n(f) of 0.17 shows that the valence of ytterbium in the neutral adduct is multiconfigurational, in reasonable agreement with a CASSCF calculation that yields a n(f) value of 0.27; that is, the two configurations in the wave function are f(13)(pi(1))(1) and f(14)(pi(1))(0) in a ratio of 0.27:0.73, respectively, and the open-shell singlet lies 0.28 eV below the triplet state (n(f) accounts for f-hole occupancy; that is, n(f) = 1 when the configuration is f(13) and n(f) = 0 when the configuration is f(14)). A correlation is outlined between the value of nf and the individual ytterbocene and bipyridine fragments such that, as the reduction potentials of the ytterbocene cation and the free x,x'-R-2-bipy ligands approach each other, the value of nf and therefore the f(13):f(14) ratio reaches a maximum; conversely, the ratio is minimized as the disparity increases.

  18. Enhanced aging properties of HKUST-1 in hydrophobic mixed-matrix membranes for ammonia adsorption† †Electronic supplementary information (ESI) available: Experimental procedures. See DOI: 10.1039/c5sc04368a Click here for additional data file.

    Science.gov (United States)

    Denny, Jr., Michael S.; Peterson, Gregory W.; Mahle, John J.

    2016-01-01

    Metal–organic frameworks (MOFs) in their free powder form have exhibited superior capacities for many gases when compared to other materials, due to their tailorable functionality and high surface areas. Specifically, the MOF HKUST-1 binds small Lewis bases, such as ammonia, with its coordinatively unsaturated copper sites. We describe here the use of HKUST-1 in mixed-matrix membranes (MMMs) prepared from polyvinylidene difluoride (PVDF) for the removal of ammonia gas. These MMMs exhibit ammonia capacities similar to their hypothetical capacities based on the weight percent of HKUST-1 in each MMM. HKUST-1 in its powder form is unstable toward humid conditions; however, upon exposure to humid environments for prolonged periods of time, the HKUST-1 MMMs exhibit outstanding structural stability, and maintain their ammonia capacity. Overall, this study has achieved all of the critical and combined elements for real-world applications of MOFs: high MOF loadings, fully accessible MOF surfaces, enhanced MOF stabilization, recyclability, mechanical stability, and processability. This study is a critical step in advancing MOFs to a stable, usable, and enabling technology. PMID:28660045

  19. Tetramethyl(perfluoroalkyl)cyclopentadienyl Rhodium(I) Complexes with Ethylene or Diene Ligands. Crystal Structure of [(eta-5-C5Me4C6F13)Rh(CO)2

    Czech Academy of Sciences Publication Activity Database

    Čermák, Jan; Krupková, Alena; Auerová, Kateřina; Zamrzla, M.; Nguyen Thi, T.H.; Vojtíšek, P.; Císařová, I.

    2010-01-01

    Roč. 695, č. 3 (2010), s. 375-381 ISSN 0022-328X R&D Projects: GA AV ČR IAA4072203; GA MŠk(CZ) LC06070 Institutional research plan: CEZ:AV0Z40720504 Keywords : fluorous cyclopentadienes * rhodium complexes * alkene complexes Subject RIV: CC - Organic Chemistry Impact factor: 2.205, year: 2010

  20. NCBI nr-aa BLAST: CBRC-OANA-01-2119 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-OANA-01-2119 ref|ZP_01307403.1| Secreted/periplasmic Zn-dependent peptidase, insulina...se-like protein [Oceanobacter sp. RED65] gb|EAT11978.1| Secreted/periplasmic Zn-dependent peptidase, insulinase-like protein [Oceanobacter sp. RED65] ZP_01307403.1 0.40 28% ...

  1. NCBI nr-aa BLAST: CBRC-OGAR-01-1183 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-OGAR-01-1183 ref|YP_420327.1| Periplasmic protein TonB [Magnetospirillum magne...ticum AMB-1] dbj|BAE49768.1| Periplasmic protein TonB [Magnetospirillum magneticum AMB-1] YP_420327.1 0.019 25% ...

  2. ORF Alignment: NC_003911 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available NC_003911 gi|56698296 >1eljA 1 332 19 332 1e-06 ... gb|AAV96699.1| polyamine ABC trasnporte...snporter, periplasmic polyamine-binding protein ... [Silicibacter pomeroyi D...r, periplasmic polyamine-binding protein ... [Silicibacter pomeroyi DSS-3] ref|YP_168669.1| polyamine ... ABC tra

  3. ORF Alignment: NC_006905 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available NC_006905 gi|62179485 >1iwlA 1 182 23 204 2e-69 ... ref|YP_215902.1| periplasmic protein effects...ica ... subsp. enterica serovar Choleraesuis str. SC-B67] ... gb|AAX64821.1| periplasmic protein effects

  4. Environmental Impact Analysis Process. Final Environmental Impact Statement for Proposed Air Force Reserve Mission Change (C-130 to C-5A Aircraft) and Westover Metropolitan Development Corporation (Expansion of Civil Aviation Operations through 1995) at Westover Air Force Base, Massachusetts. Volume 1

    Science.gov (United States)

    1987-04-01

    many of which would not be acceptable under current environmental regula- tions but which were in compliance with the standards in effect at tK2 ...waste management regulations and issued a Notice of Violation (NOV) citing specific deficiencies in hazardous waste management procedures. The focus of...materials are handled and disposed of in compliance with applicable federal, state, and local regulations. Specific deficiencies cited in the NOV included

  5. A dual-response BODIPY-based fluorescent probe for the discrimination of glutathione from cystein and homocystein† †Electronic supplementary information (ESI) available: Synthesis, spectroscopic properties, NMR and mass spectra. See DOI: 10.1039/c5sc00216h Click here for additional data file.

    Science.gov (United States)

    Wang, Feiyi; Zhou, Li; Wang, Rui; Fei, Qiang; Luo, Sihang; Guo, Zhiqian; Tian, He

    2015-01-01

    In situ monitoring of intracellular thiol activity in cell growth and function is highly desirable. However, the discriminative detection of glutathione (GSH) from cysteine (Cys) and homocystein (Hcy) and from common amino acids still remains a challenge due to the similar reactivity of the thiol groups in these amino acids. Here we report a novel strategy for selectively sensing GSH by a dual-response mechanism. Integrating two independent reaction sites with a disulfide linker and a thioether function into a fluorescent BODIPY-based chemsensor can guarantee the synergetic dual-response in an elegant fashion to address the discrimination of GSH. In the first synergetic reaction process, the thiol group in GSH, Cys and Hcy induces disulfide cleavage and subsequent intramolecular cyclization to release the unmasked phenol-based BODIPY (discriminating thiol amino acids from other amino acids). In the second synergetic process, upon the substitution of the thioether with the nucleophilic thiolate to form a sulfenyl-BODIPY, only the amino groups of Cys and Hcy, but not that of GSH, undergo a further intramolecular displacement to yield an amino-substituted BODIPY. In this way, we make full use of the kinetically favorable cyclic transition state in the intramolecular rearrangement, and enable photophysical distinction between sulfenyl- and amino-substituted BODIPY for allowing the discriminative detection of GSH over Cys and Hcy and thiol-lacking amino acids under physiological conditions. Moreover, this probe exhibits a distinguishable ratiometric fluorescence pattern generated from the orange imaging channel to the red channel, which proves the differentiation of GSH from Cys and Hcy in living cells. PMID:29560246

  6. The AT-Hook motif as a versatile minor groove anchor for promoting DNA binding of transcription factor fragments? ?Electronic supplementary information (ESI) available: Peptide synthesis, full experimental procedures and analytical data of the peptides and products obtained. See DOI: 10.1039/c5sc01415h Click here for additional data file.

    OpenAIRE

    Rodr?guez, J?ssica; Mosquera, Jes?s; Couceiro, Jose R.; V?zquez, M. Eugenio; Mascare?as, Jos? L.

    2015-01-01

    We report the development of chimeric DNA binding peptides comprising a DNA binding fragment of natural transcription factors (the basic region of a bZIP protein or a monomeric zinc finger module) and an AT-Hook peptide motif. The resulting peptide conjugates display high DNA affinity and excellent sequence selectivity. Furthermore, the AT-Hook motif also favors the cell internalization of the conjugates.

  7. Thermodynamics of amine + ketone mixtures: Volumetric, speed of sound data and viscosity at 303.15 K and 308.15 K for the binary mixtures of N,N-diethylaniline + aliphatic ketones (C3–C5 + 4-methyl-2-pentanone

    Directory of Open Access Journals (Sweden)

    Manukonda Gowrisankar

    2017-05-01

    Full Text Available Measurement of densities (ρ, viscosities (η, and ultrasonic speeds (u has been carried out for binary mixtures of N,N-diethylaniline (N,N-DEA with acetone (AC, methylethylketone (MEK, methylpropylketone (MPK, diethylketone (DEK, and methylisobutylketone (MIBK, and their pure liquids at 303.15 K and 308.15 K over the entire composition range. These experimental values have been used to calculate the excess molar volume (VE, deviation in ultrasonic speeds (Δu, deviation in isentropic compressibility (Δκs, deviation in intermolecular free length (ΔLf, deviation in acoustic impedance (ΔZ, excess Gibbs free energy of activation of viscous flow (G∗E and deviation in viscosity (Δη. The variation of these properties with composition of the mixtures suggests dipole–dipole interactions and charge-transfer complex formation between N,N-diethylaniline and dipolar ketones. The magnitude of the property is found to depend on the chain length of the ketones’ molecule. The viscosity data have been correlated using three equations: Grunberg and Nissan, Katti and Chaudhri and Hind et al. These results have been fitted to the Redlich–Kister polynomial using multiparametric nonlinear regression analysis to estimate the binary coefficients and standard errors.

  8. Post-synthetic halide conversion and selective halogen capture in hybrid perovskites† †Electronic supplementary information (ESI) available. CCDC 1048945–1048947. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c5sc01135c

    Science.gov (United States)

    Solis-Ibarra, D.; Smith, I. C.

    2015-01-01

    Reaction with halogen vapor allows us to post-synthetically exchange halides in both three- (3D) and two-dimensional (2D) organic–inorganic metal-halide perovskites. Films of 3D Pb–I perovskites cleanly convert to films of Pb–Br or Pb–Cl perovskites upon exposure to Br2 or Cl2 gas, respectively. This gas–solid reaction provides a simple method to produce the high-quality Pb–Br or Pb–Cl perovskite films required for optoelectronic applications. Reactivity with halogens can be extended to the organic layers in 2D metal-halide perovskites. Here, terminal alkene groups placed between the inorganic layers can capture Br2 gas through chemisorption to form dibromoalkanes. This reaction's selectivity for Br2 over I2 allows us to scrub Br2 to obtain high-purity I2 gas streams. We also observe unusual halogen transfer between the inorganic and organic layers within a single perovskite structure. Remarkably, the perovskite's crystallinity is retained during these massive structural rearrangements. PMID:29218171

  9. 5-Fluoro-6′H,7′H,8′H-spiro[indoline-3,7′-pyrano[3,2-c:5,6-c′]di-1-benzopyran]-2,6′,8′-trione

    Directory of Open Access Journals (Sweden)

    J. Suresh

    2012-03-01

    Full Text Available In the title compound, C26H12FNO6, the central pyran ring and both benzopyran systems are nonplanar, having total puckering amplitudes of 0.139 (2, 0.050 (1 and 0.112 (2 Å, respectively. The central pyran ring adopts a boat conformation. The crystal structure is stabilized by C—H...O, N—H...O, N—H...F and C—H...π interactions.

  10. Can acyclic conformational control be achieved via a sulfur–fluorine gauche effect?† †Electronic supplementary information (ESI) available. CCDC 1048074–1048078. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c5sc00871a

    Science.gov (United States)

    Thiehoff, C.; Holland, M. C.; Daniliuc, C.

    2015-01-01

    The gauche conformation of the 1,2-difluoroethane motif is known to involve stabilising hyperconjugative interactions between donor (bonding, σC–H) and acceptor (antibonding, σ*C–F) orbitals. This model rationalises the generic conformational preference of F–Cβ–Cα–X systems (φFCCX ≈ 60°), where X is an electron deficient substituent containing a Period 2 atom. Little is known about the corresponding Period 3 systems, such as sulfur and phosphorus, where multiple oxidation states are possible. Conformational analyses of β-fluorosulfides, -sulfoxides and -sulfones are disclosed here, thus extending the scope of the fluorine gauche effect to the 3rd Period (F–C–C–S(O)n; φFCCS ≈ 60°). Synergy between experiment and computation has revealed that the gauche effect is only pronounced in structures bearing an electropositive vicinal sulfur atom (S+–O–, SO2). PMID:29511517

  11. Recalculation of loads on LOFT penetrations 1A, 2A, 3E, 3F, 5A, 5B, 5C, 5D, 5E, 5F, 7A, 9A, 11C, 17A, 17B, 20A, 20B, 20C, 21A

    International Nuclear Information System (INIS)

    McFadden, D.F.

    1978-01-01

    The loads on the piping nozzles penetrating the LOFT containment vessel are presented. Since the design and construction of the containment vessel, piping systems that penetrate the nozzles have been changed. Consequently, the moments and forces on the containment vessel are different than those stated in LOFT specification S-1. Two combined load cases were tabulated, deadweight plus thermal expansion plus operating basis earthquake and deadweight plus safe shutdown earthquake

  12. Thermally-responsive, nonflammable phosphonium ionic liquid electrolytes for lithium metal batteries: operating at 100 degrees celsius† †Electronic supplementary information (ESI) available: Detailed ionic liquids synthesis, characterization, conductivity, cyclic voltammetry, battery cycling and those of other compositions; SEM images; energy density calculation. See DOI: 10.1039/c5sc01518a Click here for additional data file.

    Science.gov (United States)

    Lin, X.; Kavian, R.; Lu, Y.; Hu, Q.; Shao-Horn, Y.

    2015-01-01

    Rechargeable batteries such as Li ion/Li metal batteries are widely used in the electronics market but the chemical instability of the electrolyte limits their use in more demanding environmental conditions such as in automotive, oil exploration, or mining applications. In this study, a series of alkyl phosphonium ionic liquid electrolyte are described with high thermal stability and solubility for LiTFSI. A lithium metal battery (LMB) containing a tailored phosphonium ionic liquid/LiTFSI electrolyte operates at 100 °C with good specific capacities and cycling stability. Substantial capacity is maintained during 70 cycles or 30 days. Instant on-off battery operation is realized via the significant temperature dependence of the electrolyte material, demonstrating the robustness and potential for use at high temperature. PMID:28757963

  13. Environmental Impact Analysis Process. Final Environmental Impact Statement for Proposed Air Force Reserve Mission Change (C-130 to C-5A Aircraft) and Westover Metropolitan Development Corporation. (Expansion of Civil Aviation Operations through 1995) at Westover Air Force Base, Massachusetts April 1987. Volume 2

    Science.gov (United States)

    1987-04-01

    and reactions to them by their peers, and this provides increased motivation for them to work to resolve problems that they cause. Each base commander...3* ft Of 040 00b Pt P.*~. 1. bD 4 4-A W ft S I 50 1 a I us * I 1S% P 4~ 0 -4*.1J @A PS4 ~%P inf m -~t~d 4 4 FS% SA E 00 If V I. t 0 5 a I. * z 0 4 ft

  14. A diversity-oriented synthesis strategy enabling the combinatorial-type variation of macrocyclic peptidomimetic scaffolds† †Electronic supplementary information (ESI) available: Experimental procedures, characterization data and details of the computational analyses. See DOI: 10.1039/c5ob00371g Click here for additional data file.

    Science.gov (United States)

    Isidro-Llobet, Albert; Hadje Georgiou, Kathy; Galloway, Warren R. J. D.; Giacomini, Elisa; Hansen, Mette R.; Méndez-Abt, Gabriela; Tan, Yaw Sing; Carro, Laura; Sore, Hannah F.

    2015-01-01

    Macrocyclic peptidomimetics are associated with a broad range of biological activities. However, despite such potentially valuable properties, the macrocyclic peptidomimetic structural class is generally considered as being poorly explored within drug discovery. This has been attributed to the lack of general methods for producing collections of macrocyclic peptidomimetics with high levels of structural, and thus shape, diversity. In particular, there is a lack of scaffold diversity in current macrocyclic peptidomimetic libraries; indeed, the efficient construction of diverse molecular scaffolds presents a formidable general challenge to the synthetic chemist. Herein we describe a new, advanced strategy for the diversity-oriented synthesis (DOS) of macrocyclic peptidomimetics that enables the combinatorial variation of molecular scaffolds (core macrocyclic ring architectures). The generality and robustness of this DOS strategy is demonstrated by the step-efficient synthesis of a structurally diverse library of over 200 macrocyclic peptidomimetic compounds, each based around a distinct molecular scaffold and isolated in milligram quantities, from readily available building-blocks. To the best of our knowledge this represents an unprecedented level of scaffold diversity in a synthetically derived library of macrocyclic peptidomimetics. Cheminformatic analysis indicated that the library compounds access regions of chemical space that are distinct from those addressed by top-selling brand-name drugs and macrocyclic natural products, illustrating the value of our DOS approach to sample regions of chemical space underexploited in current drug discovery efforts. An analysis of three-dimensional molecular shapes illustrated that the DOS library has a relatively high level of shape diversity. PMID:25778821

  15. Overpotential for CO2 electroreduction lowered on strained penta-twinned Cu nanowires? ?Electronic supplementary information (ESI) available: Details of DFT and MD calculations, CHE model and reaction pathways for C2H4 production. See DOI: 10.1039/c5sc02667a Click here for additional data file.

    OpenAIRE

    Chen, Zhengzheng; Zhang, Xu; Lu, Gang

    2015-01-01

    Based on first-principles calculations, we predict that penta-twinned Cu nanowires (NWs) are superior to conventional Cu catalysts for CO2 electroreduction. The penta-twinned NWs possess a combination of ultrahigh mechanical strength, large surface-to-volume ratios and an abundance of undercoordinated adsorption sites, all desirable for CO2 electroreduction. In particular, we show that the penta-twinned Cu NWs can withstand elastic strains orders of magnitude higher than their conventional co...

  16. Overpotential for CO2 electroreduction lowered on strained penta-twinned Cu nanowires† †Electronic supplementary information (ESI) available: Details of DFT and MD calculations, CHE model and reaction pathways for C2H4 production. See DOI: 10.1039/c5sc02667a Click here for additional data file.

    Science.gov (United States)

    Chen, Zhengzheng; Zhang, Xu

    2015-01-01

    Based on first-principles calculations, we predict that penta-twinned Cu nanowires (NWs) are superior to conventional Cu catalysts for CO2 electroreduction. The penta-twinned NWs possess a combination of ultrahigh mechanical strength, large surface-to-volume ratios and an abundance of undercoordinated adsorption sites, all desirable for CO2 electroreduction. In particular, we show that the penta-twinned Cu NWs can withstand elastic strains orders of magnitude higher than their conventional counterpart, and as a result their CO2 electroreduction activities can be significantly enhanced by elastic tensile strains. With a moderate tensile strain, the bias potential for methane production at a decent current density (2 mA cm–2) can be reduced by 50%. On the other hand, the competing hydrogen evolution reaction can be suppressed by the tensile strains. The presence of H at the NW surface is found to have a minor effect on CO2 electroreduction. Finally, we propose to use graphene as a substrate to stretch deposited Cu NWs. PMID:28757974

  17. Synthesis of N-(β-D-glycuronopyranosyl)alkanamides and 1-(β-D-glycuronopyranosyl)-4-phenyl-[1,2,3]-triazoles as N-glycoprotein linkage region analogs: examination of the effect of C5 substituent on the N-glycosidic torsion (ΦN) based on X-ray crystallography.

    Science.gov (United States)

    Mathiselvam, Manoharan; Loganathan, Duraikkannu; Varghese, Babu

    2013-10-18

    The torsion angle around the N-glycoprotein linkage region (GlcNAc-Asn) is an important factor for presenting sugar on the cell surface which is crucial for many biological processes. Earlier studies using model and analogs showed that this important torsion angle is greatly influenced by substitutions in the sugar part. In the present work, uronic acid alkanamides and triazole derivatives have been designed and synthesized as newer analogs of N-glycoprotein linkage region to understand the influence of the carboxylic group on linkage region torsion as well as on molecular packing. Crystal structure of N-(β-D-galacturonopyranosyl)acetamide is solved with the space group of P22121. Comparison of the torsion angle and molecular packing of this compound with N-(β-D-galactopyranosyl)acetamide showed that changing the C6-hydoxymethyl group to the carboxylic acid group has minimum influence on the N-glycosidic torsion angle, ΦN and significant influence on the molecular packing. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Semiconductive 3-D haloplumbate framework hybrids with high color rendering index white-light emission† †Electronic supplementary information (ESI) available. CCDC 1055380 and 1055381. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c5sc02501j Click here for additional data file. Click here for additional data file.

    Science.gov (United States)

    Wang, Guan-E; Wang, Ming-Sheng; Cai, Li-Zhen; Li, Wen-Hua

    2015-01-01

    Single-component white light materials may create great opportunities for novel conventional lighting applications and display systems; however, their reported color rendering index (CRI) values, one of the key parameters for lighting, are less than 90, which does not satisfy the demand of color-critical upmarket applications, such as photography, cinematography, and art galleries. In this work, two semiconductive chloroplumbate (chloride anion of lead(ii)) hybrids, obtained using a new inorganic–organic hybrid strategy, show unprecedented 3-D inorganic framework structures and white-light-emitting properties with high CRI values around 90, one of which shows the highest value to date. PMID:28757985

  19. Using a biomimetic membrane surface experiment to investigate the activity of the magnetite biomineralisation protein Mms6† †Electronic supplementary information (ESI) available: Including Mms6 protein and peptide sequences, additional QCM-D and SEM data and protein modelling. See DOI: 10.1039/c5ra16469a Click here for additional data file.

    Science.gov (United States)

    Bird, Scott M.; Rawlings, Andrea E.; Galloway, Johanna M.

    2016-01-01

    Magnetotactic bacteria are able to synthesise precise nanoparticles of the iron oxide magnetite within their cells. These particles are formed in dedicated organelles termed magnetosomes. These lipid membrane compartments use a range of biomineralisation proteins to nucleate and regulate the magnetite crystallisation process. A key component is the membrane protein Mms6, which binds to iron ions and helps to control the formation of the inorganic core. We have previously used Mms6 on gold surfaces patterned with a self-assembled monolayer to successfully produce arrays of magnetic nanoparticles. Here we use this surface system as a mimic of the interior face of the magnetosome membrane to study differences between intact Mms6 and the acid-rich C-terminal peptide subregion of the Mms6 protein. When immobilised on surfaces, the peptide is unable to reproduce the particle size or homogeneity control exhibited by the full Mms6 protein in our experimental setup. Moreover, the peptide is unable to support anchoring of a dense array of nanoparticles to the surface. This system also allows us to deconvolute particle binding from particle nucleation, and shows that Mms6 particle binding is less efficient when supplied with preformed magnetite nanoparticles when compared to particles precipitated from solution in the presence of the surface immobilised Mms6. This suggests that Mms6 binds to iron ions rather than to magnetite surfaces in our system, and is perhaps a nucleating agent rather than a controller of magnetite crystal growth. The comparison between the peptide and the protein under identical experimental conditions indicates that the full length sequence is required to support the full function of Mms6 on surfaces. PMID:27019707

  20. Macropolyhedral boron-containing cluster chemistry. The unique nido-five-vertex-< B-2 >-nido-ten-vertex conjuncto structure of [(eta(5)-C5Me5)(2)Rh2B11H15] via an unexpected cluster-dismantling

    Czech Academy of Sciences Publication Activity Database

    Carr, MJ.; Perera, SD.; Jelínek, Tomáš; Štíbr, Bohumil; Clegg, W.; Kilner, C. A.; Kennedy, D. J.

    2007-01-01

    Roč. 34, - (2007), s. 3559-3561 ISSN 1359-7345 R&D Projects: GA ČR GA203/05/2646; GA AV ČR(CZ) IAA400320601 Grant - others:EPSRC(GB) J/56929; EPSRC(GB) GR/L/49505; EPSRC(GB) R/61949 Institutional research plan: CEZ:AV0Z40320502 Keywords : nuclear magnetic resonance Subject RIV: CA - Inorganic Chemistry Impact factor: 5.141, year: 2007

  1. YidC is in involved in the biogenesis of the secreted autotransporter Hemoglobin Protease

    NARCIS (Netherlands)

    Jong, W.S.P.; ten Hagen-Jongman ten, C.M.; Ruijter, E.; Orru, R.V.A.; Genevaux, P.; Luirink, S.

    2010-01-01

    Autotransporters (ATs) constitute an important family of virulence factors secreted by Gram-negative bacteria. Following their translocation across the inner membrane (IM), ATs temporarily reside in the periplasmic space after which they are secreted into the extracellular environment. Previous

  2. Sequence Classification: 488452 [

    Lifescience Database Archive (English)

    Full Text Available TMB Non-TMH TMB TMB TMB TMB >gi|28869747|ref|NP_792366.1| phosphonates ABC transpor...ter, periplasmic phosphonates-binding protein || http://www.ncbi.nlm.nih.gov/protein/28869747 ...

  3. Sequence Classification: 206174 [

    Lifescience Database Archive (English)

    Full Text Available TMB Non-TMH TMB TMB TMB TMB >gi|16124617|ref|NP_419181.1| phosphonates ABC transpor...ter, periplasmic phosphonates-binding protein || http://www.ncbi.nlm.nih.gov/protein/16124617 ...

  4. Characterization and distribution of esterase activity in activated sludge

    NARCIS (Netherlands)

    Boczar, BA; Forney, LJ; Begley, WM; Larson, RJ; Federle, TW

    2001-01-01

    The location and activity of esterase enzymes in activated Sludge from three Municipal wastewater treatment plants were characterized using model Substrate, and denaturing and nondenaturing polyacrylamide gel electrophoresis (PAGE) Of particulate, freeze thaw (primarily periplasmic enzymes and those

  5. ORF Sequence: NC_002655 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available NC_002655 gi|15800754 >gi|15800754|ref|NP_286768.1| periplasmic protein effects translocation of lipoprotei...ns from inner membrane to outer [Escherichia coli O157:H7 EDL933] MMKKIAITCALLSSLVA

  6. ORF Sequence: NC_000913 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available NC_000913 gi|16128858 >gi|16128858|ref|NP_415411.1| periplasmic chaperone effects translocation of lipoprot...eins from inner membrane to outer membrane [Escherichia coli K12] MMKKIAITCALLSSLVA

  7. ORF Sequence: NC_006905 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available NC_006905 gi|62179485 >gi|62179485|ref|YP_215902.1| periplasmic protein effects translocation of lipoprotei...ns from inner membrane to outer membrane [Salmonella enterica subsp. enterica serov

  8. Efficient functionalization of alginate biomaterials.

    Science.gov (United States)

    Dalheim, Marianne Ø; Vanacker, Julie; Najmi, Maryam A; Aachmann, Finn L; Strand, Berit L; Christensen, Bjørn E

    2016-02-01

    Peptide coupled alginates obtained by chemical functionalization of alginates are commonly used as scaffold materials for cells in regenerative medicine and tissue engineering. We here present an alternative to the commonly used carbodiimide chemistry, using partial periodate oxidation followed by reductive amination. High and precise degrees of substitution were obtained with high reproducibility, and without formation of by-products. A protocol was established using l-Tyrosine methyl ester as a model compound and the non-toxic pic-BH3 as the reducing agent. DOSY was used to indirectly verify covalent binding and the structure of the product was further elucidated using NMR spectroscopy. The coupling efficiency was to some extent dependent on alginate composition, being most efficient on mannuronan. Three different bioactive peptide sequences (GRGDYP, GRGDSP and KHIFSDDSSE) were coupled to 8% periodate oxidized alginate resulting in degrees of substitution between 3.9 and 6.9%. Cell adhesion studies of mouse myoblasts (C2C12) and human dental stem cells (RP89) to gels containing various amounts of GRGDSP coupled alginate demonstrated the bioactivity of the material where RP89 cells needed higher peptide concentrations to adhere. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Interactive surface in the PapD chaperone cleft is conserved in pilus chaperone superfamily and essential in subunit recognition and assembly.

    OpenAIRE

    Slonim, L N; Pinkner, J S; Brändén, C I; Hultgren, S J

    1992-01-01

    The assembly of adhesive pili in Gram-negative bacteria is modulated by specialized periplasmic chaperone systems. PapD is the prototype member of the superfamily of periplasmic pilus chaperones. Previously, the alignment of chaperone sequences superimposed on the three dimensional structure of PapD revealed the presence of invariant, conserved and variable amino acids. Representative residues that protruded into the PapD cleft were targeted for site directed mutagenesis to investigate the pi...

  10. Molecular glues for manipulating enzymes: trypsin inhibition by benzamidine-conjugated molecular glues† †Electronic supplementary information (ESI) available: Synthesis of TEG–BA, Gluen–BA, mGluen–BA and Gluen–Ph; 1H NMR, 13C NMR, MALDI-TOF MS, electronic absorption, and CD spectra; zeta potential distributions; SLS plots; DLS histograms; and related experimental procedures. See DOI: 10.1039/c5sc00524h Click here for additional data file.

    Science.gov (United States)

    Mogaki, Rina

    2015-01-01

    Water-soluble bioadhesive polymers bearing multiple guanidinium ion (Gu+) pendants at their side-chain termini (Gluen–BA, n = 10 and 29) that were conjugated with benzamidine (BA) as a trypsin inhibitor were developed. The Gluen–BA molecules are supposed to adhere to oxyanionic regions of the trypsin surface, even in buffer, via a multivalent Gu+/oxyanion salt-bridge interaction, such that their BA group properly blocks the substrate-binding site. In fact, Glue10–BA and Glue29–BA exhibited 35- and 200-fold higher affinities for trypsin, respectively, than a BA derivative without the glue moiety (TEG–BA). Most importantly, Glue10–BA inhibited the protease activity of trypsin 13-fold more than TEG–BA. In sharp contrast, mGlue27–BA, which bears 27 Gu+ units along the main chain and has a 5-fold higher affinity than TEG–BA for trypsin, was inferior even to TEG–BA for trypsin inhibition. PMID:28706668

  11. High throughput imaging cytometer with acoustic focussing† †Electronic supplementary information (ESI) available: High throughput imaging cytometer with acoustic focussing. See DOI: 10.1039/c5ra19497k Click here for additional data file. Click here for additional data file. Click here for additional data file. Click here for additional data file. Click here for additional data file. Click here for additional data file. Click here for additional data file. Click here for additional data file.

    Science.gov (United States)

    Zmijan, Robert; Jonnalagadda, Umesh S.; Carugo, Dario; Kochi, Yu; Lemm, Elizabeth; Packham, Graham; Hill, Martyn

    2015-01-01

    We demonstrate an imaging flow cytometer that uses acoustic levitation to assemble cells and other particles into a sheet structure. This technique enables a high resolution, low noise CMOS camera to capture images of thousands of cells with each frame. While ultrasonic focussing has previously been demonstrated for 1D cytometry systems, extending the technology to a planar, much higher throughput format and integrating imaging is non-trivial, and represents a significant jump forward in capability, leading to diagnostic possibilities not achievable with current systems. A galvo mirror is used to track the images of the moving cells permitting exposure times of 10 ms at frame rates of 50 fps with motion blur of only a few pixels. At 80 fps, we demonstrate a throughput of 208 000 beads per second. We investigate the factors affecting motion blur and throughput, and demonstrate the system with fluorescent beads, leukaemia cells and a chondrocyte cell line. Cells require more time to reach the acoustic focus than beads, resulting in lower throughputs; however a longer device would remove this constraint. PMID:29456838

  12. DNA origami based Au–Ag-core–shell nanoparticle dimers with single-molecule SERS sensitivity† †Electronic supplementary information (ESI) available: Additional information about materials and methods, designs of DNA origami templates, height profiles, additional SERS spectra, assignment of DNA bands, SEM images, additional AFM images, FDTD simulations, additional reference spectra for Cy3 and detailed description of EF estimation, simulated absorption and scattering spectra. See DOI: 10.1039/c5nr08674d Click here for additional data file.

    Science.gov (United States)

    Prinz, J.; Heck, C.; Ellerik, L.; Merk, V.

    2016-01-01

    DNA origami nanostructures are a versatile tool to arrange metal nanostructures and other chemical entities with nanometer precision. In this way gold nanoparticle dimers with defined distance can be constructed, which can be exploited as novel substrates for surface enhanced Raman scattering (SERS). We have optimized the size, composition and arrangement of Au/Ag nanoparticles to create intense SERS hot spots, with Raman enhancement up to 1010, which is sufficient to detect single molecules by Raman scattering. This is demonstrated using single dye molecules (TAMRA and Cy3) placed into the center of the nanoparticle dimers. In conjunction with the DNA origami nanostructures novel SERS substrates are created, which can in the future be applied to the SERS analysis of more complex biomolecular targets, whose position and conformation within the SERS hot spot can be precisely controlled. PMID:26892770

  13. Triazolophostins: a library of novel and potent agonists of IP3 receptors? ?Electronic supplementary information (ESI) available: Synthetic procedures and spectral data for all new compounds, crystal data for disaccharide 4 and details of the docking study. CCDC 1022279. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c5ob00440c Click here for additional data file. Click here for additional data file.

    OpenAIRE

    Vibhute, Amol M.; Konieczny, Vera; Taylor, Colin W.; Sureshan, Kana M.

    2015-01-01

    IP3 receptors are channels that mediate the release of Ca2+ from the intracellular stores of cells stimulated by hormones or neurotransmitters. Adenophostin A (AdA) is the most potent agonist of IP3 receptors, with the ?-anomeric adenine contributing to the increased potency. The potency of AdA and its stability towards the enzymes that degrade IP3 have aroused interest in AdA analogs for biological studies. The complex structure of AdA poses problems that have necessitated optimization of sy...

  14. Evidence for an intermediate conformational state of LacY.

    Science.gov (United States)

    Jiang, Xiaoxu; Guan, Lan; Zhou, Yonggang; Hong, Wen-Xu; Zhang, Qinghai; Kaback, H Ronald

    2012-03-20

    LacY mutant Cys154 → Gly exhibits a periplasmic-closed crystal structure identical to the WT, but is periplasmic-open in the membrane. The mutant hardly catalyzes transport, but binds galactosides from either side of the membrane with the same affinity and is resistant to site-directed proteolysis relative to the pseudo-WT. Site-directed alkylation was also applied to 11 single-Cys mutants in Cys154 → Gly LacY in right-side-out membrane vesicles or after solubilization and purification in dodecyl-β-D-maltopyranoside (DDM). Unlike the pseudo-WT, Cys replacements on the periplasmic side of the Cys154 → Gly mutant label rapidly in the membrane without sugar, but labeling decreases markedly after the mutant proteins are purified. Thus, Cys154 → Gly LacY likely favors a higher-energy intermediate periplasmic-open conformation in situ, but collapses to a lower-energy periplasmic-closed conformation in DDM after purification. Notably, branched-chain or neopentyl glycol maltoside detergents stabilize Cys154 → Gly LacY in the membrane-embedded form.

  15. The Lack of the Essential LptC Protein in the Trans-Envelope Lipopolysaccharide Transport Machine Is Circumvented by Suppressor Mutations in LptF, an Inner Membrane Component of the Escherichia coli Transporter

    KAUST Repository

    Benedet, Mattia

    2016-08-16

    The lipopolysaccharide (LPS) transport (Lpt) system is responsible for transferring LPS from the periplasmic surface of the inner membrane (IM) to the outer leaflet of the outer membrane (OM), where it plays a crucial role in OM selective permeability. In E. coli seven essential proteins are assembled in an Lpt trans-envelope complex, which is conserved in gamma-Proteobacteria. LptBFG constitute the IMABC transporter, LptDE form the OM translocon for final LPS delivery, whereas LptC, an IM-anchored protein with a periplasmic domain, interacts with the IM ABC transporter, the periplasmic protein LptA, and LPS. Although essential, LptC can tolerate several mutations and its role in LPS transport is unclear. To get insights into the functional role of LptC in the Lpt machine we searched for viable mutants lacking LptC by applying a strong double selection for lptC deletion mutants. Genome sequencing of viable Delta lptC mutants revealed single amino acid substitutions at a unique position in the predicted large periplasmic domain of the IM component LptF (LptF(SupC)). In complementation tests, lptF(SupC) mutants suppress lethality of both Delta lptC and lptC conditional expressionmutants. Our data show that mutations in a specific residue of the predicted LptF periplasmic domain can compensate the lack of the essential protein LptC, implicate such LptF domain in the formation of the periplasmic bridge between the IM and OM complexes, and suggest that LptC may have evolved to improve the performance of an ancestral six-component Lpt machine.

  16. The Lack of the Essential LptC Protein in the Trans-Envelope Lipopolysaccharide Transport Machine Is Circumvented by Suppressor Mutations in LptF, an Inner Membrane Component of the Escherichia coli Transporter

    KAUST Repository

    Benedet, Mattia; Falchi, Federica A.; Puccio, Simone; Di Benedetto, Cristiano; Peano, Clelia; Polissi, Alessandra; Deho, Gianni

    2016-01-01

    The lipopolysaccharide (LPS) transport (Lpt) system is responsible for transferring LPS from the periplasmic surface of the inner membrane (IM) to the outer leaflet of the outer membrane (OM), where it plays a crucial role in OM selective permeability. In E. coli seven essential proteins are assembled in an Lpt trans-envelope complex, which is conserved in gamma-Proteobacteria. LptBFG constitute the IMABC transporter, LptDE form the OM translocon for final LPS delivery, whereas LptC, an IM-anchored protein with a periplasmic domain, interacts with the IM ABC transporter, the periplasmic protein LptA, and LPS. Although essential, LptC can tolerate several mutations and its role in LPS transport is unclear. To get insights into the functional role of LptC in the Lpt machine we searched for viable mutants lacking LptC by applying a strong double selection for lptC deletion mutants. Genome sequencing of viable Delta lptC mutants revealed single amino acid substitutions at a unique position in the predicted large periplasmic domain of the IM component LptF (LptF(SupC)). In complementation tests, lptF(SupC) mutants suppress lethality of both Delta lptC and lptC conditional expressionmutants. Our data show that mutations in a specific residue of the predicted LptF periplasmic domain can compensate the lack of the essential protein LptC, implicate such LptF domain in the formation of the periplasmic bridge between the IM and OM complexes, and suggest that LptC may have evolved to improve the performance of an ancestral six-component Lpt machine.

  17. Structural Basis for a Ribofuranosyl Binding Protein: Insights into the Furanose Specific Transport

    Energy Technology Data Exchange (ETDEWEB)

    Bagaria, A.; Swaminathan, S.; Kumaran, D.; Burley, S. K.

    2011-04-01

    The ATP-binding cassette transporters (ABC-transporters) are members of one of the largest protein superfamilies, with representatives in all extant phyla. These integral membrane proteins utilize the energy of ATP hydrolysis to carry out certain biological processes, including translocation of various substrates across membranes and non-transport related processes such as translation of RNA and DNA repair. Typically, such transport systems in bacteria consist of an ATP binding component, a transmembrane permease, and a periplasmic receptor or binding protein. Soluble proteins found in the periplasm of gram-negative bacteria serve as the primary receptors for transport of many compounds, such as sugars, small peptides, and some ions. Ligand binding activates these periplasmic components, permitting recognition by the membrane spanning domain, which supports for transport and, in some cases, chemotaxis. Transport and chemotaxis processes appear to be independent of one another, and a few mutants of bifunctional periplasmic components reveal the absence of one or the other function. Previously published high-resolution X-ray structures of various periplasmic ligand binding proteins include Arabinose binding protein (ABP), Allose binding protein (ALBP), Glucose-galactose binding protein (GBP) and Ribose binding protein (RBP). Each of these proteins consists of two structurally similar domains connected by a three-stranded hinge region, with ligand buried between the domains. Upon ligand binding and release, various conformational changes have been observed. For RBP, open (apo) and closed (ligand bound) conformations have been reported and so for MBP. The closed/active form of the protein interacts with the integral membrane component of the system in both transport and chemotaxis. Herein, we report 1.9{angstrom} resolution X-ray structure of the R{sub f}BP periplasmic component of an ABC-type sugar transport system from Hahella chejuensis (UniProt Id Q2S7D2) bound to

  18. Cytoplasmic Histidine Kinase (HP0244)-Regulated Assembly of Urease with UreI, a Channel for Urea and Its Metabolites, CO2, NH3, and NH4+, Is Necessary for Acid Survival of Helicobacter pylori▿

    OpenAIRE

    Scott, David R.; Marcus, Elizabeth A.; Wen, Yi; Singh, Siddarth; Feng, Jing; Sachs, George

    2009-01-01

    Helicobacter pylori colonizes the normal human stomach by maintaining both periplasmic and cytoplasmic pH close to neutral in the presence of gastric acidity. Urease activity, urea flux through the pH-gated urea channel, UreI, and periplasmic α-carbonic anhydrase are essential for colonization. Exposure to pH 4.5 for up to 180 min activates total bacterial urease threefold. Within 30 min at pH 4.5, the urease structural subunits, UreA and UreB, and the Ni2+ insertion protein, UreE, are recrui...

  19. The substrate-binding protein imposes directionality on an electrochemical sodium gradient-driven TRAP transporter

    NARCIS (Netherlands)

    Mulligan, Christopher; Geertsma, Eric R.; Severi, Emmanuele; Kelly, David J.; Poolman, Bert; Thomas, Gavin H.

    2009-01-01

    Substrate-binding protein-dependent secondary transporters are widespread in prokaryotes and are represented most frequently by members of the tripartite ATP-independent periplasmic (TRAP) transporter family. Here, we report the membrane reconstitution of a TRAP transporter, the sialic acid-specific

  20. Maltose-binding protein effectively stabilizes the partially closed conformation of the ATP-binding cassette transporter MalFGK2

    KAUST Repository

    Weng, Jingwei; Gu, Shuo; Gao, Xin; Huang, Xuhui; Wang, Wenning

    2017-01-01

    Maltose transporter MalFGK2 is a type-I importer in the ATP-binding cassette (ABC) transporter superfamily. Upon the binding of its periplasmic binding protein, MalE, the ATPase activity of MalFGK2 can be greatly enhanced. Crystal structures of the MalFGK2-MalE-maltose complex in a so-called