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Sample records for alternative 2-c-methyl-d-erythritol 4-phosphate

  1. Cloning and characterization of the 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway genes of a natural-rubber producing plant, Hevea brasiliensis.

    PubMed

    Sando, Tomoki; Takeno, Shinya; Watanabe, Norie; Okumoto, Hiroshi; Kuzuyama, Tomohisa; Yamashita, Atsushi; Hattori, Masahira; Ogasawara, Naotake; Fukusaki, Eiichiro; Kobayashi, Akio

    2008-11-01

    Natural rubber is synthesized as rubber particles in the latex, the fluid cytoplasm of laticifers, of Hevea brasiliensis. Although it has been found that natural rubber is biosynthesized through the mevalonate pathway, the involvement of an alternative 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway is uncertain. We obtained all series of the MEP pathway candidate genes by analyzing expressed sequence tag (EST) information and degenerate PCR in H. brasiliensis. Complementation experiments with Escherichia coli mutants were performed to confirm the functions of the MEP pathway gene products of H. brasiliensis together with those of Arabidopsis thaliana, and it was found that 1-deoxy-D-xylulose-5-phosphate reductoisomerase, 2-C-methyl-D-erythritol 4-phosphate cytidylyltransferase, and 2-C-methyl-D-erythritol 2,4-cyclodiphosphate synthase of H. brasiliensis were functionally active in the E. coli mutants. Gene expression analysis revealed that the expression level of the HbDXS2 gene in latex was relatively high as compared to those of other MEP pathway genes. However, a feeding experiment with [1-(13)C] 1-deoxy-D-xylulose triacetate, an intermediate derivative of the MEP pathway, indicated that the MEP pathway is not involved in rubber biosynthesis, but is involved in carotenoids biosynthesis in H. brasiliensis.

  2. The Mycobacterium tuberculosis MEP (2C-methyl-D-erythritol 4-phosphate) pathway as a new drug target

    PubMed Central

    Eoh, Hyungjin; Brennan, Patrick J.; Crick, Dean C.

    2009-01-01

    Tuberculosis (TB) is still a major public health problem, compounded by the human immunodeficiency virus (HIV)-TB co-infection and recent emergence of multidrug-resistant (MDR) and extensive drug resistant (XDR)-TB. Novel anti-TB drugs are urgently required. In this context, the 2C-methyl-D-erythritol 4-phosphate (MEP) pathway of Mycobacterium tuberculosis has drawn attention; it is one of several pathways vital for M. tuberculosis viability and the human host lacks homologous enzymes. Thus, the MEP pathway promises bacterium-specific drug targets and the potential for identification of lead compounds unencumbered by target-based toxicity. Indeed, fosmidomycin is now known to inhibit the second step in the MEP pathway. This review describes the cardinal features of the main enzymes of the MEP pathway in M. tuberculosis and how these can be manipulated in high throughput screening campaigns in the search for new anti-infectives against TB. PMID:18793870

  3. Novel bioassay for the discovery of inhibitors of the 2-C-Methyl-D-Erythritol 4-Phosphate (MEP) and terpenoid pathways leading to carotenoid biosynthesis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway leads to the synthesis of isopentenyl-phosphate (IPP) in plastids. It is a major branch point providing precursors for the synthesis of carotenoids, tocopherols, plastoquinone and the phytyl chain of chlorophylls, as well as the hormones abscisi...

  4. Deuterium-labelled isotopomers of 2-C-methyl-D-erythritol as tools for the elucidation of the 2-C-methyl-D-erythritol 4-phosphate pathway for isoprenoid biosynthesis.

    PubMed Central

    Charon, L; Hoeffler, J F; Pale-Grosdemange, C; Lois, L M; Campos, N; Boronat, A; Rohmer, M

    2000-01-01

    Escherichia coli synthesizes its isoprenoids via the mevalonate-independent 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway. The MC4100dxs::CAT strain, defective in deoxyxylulose-5-phosphate synthase, which is the first enzyme in this metabolic route, exclusively synthesizes its isoprenoids from exogenous 2-C-methyl-D-erythritol (ME) added to the culture medium. The fate of the hydrogen atoms in the MEP pathway was followed by the incorporation of [1,1-(2)H(2)]ME and [3,5,5,5-(2)H(4)]ME. The two C-1 hydrogen atoms of ME were found without any loss in the prenyl chain of menaquinone and/or ubiquinone on the carbon atoms derived from C-4 of isopentenyl diphosphate (IPP) and on the E-methyl group of dimethylallyl diphosphate (DMAPP), the C-5 hydrogen atoms on the methyl groups derived from IPP C-5 methyl group and the Z-methyl group of DMAPP. This showed that no changes in the oxidation state of these carbon atoms occurred in the reaction sequence between MEP and IPP. Furthermore, no deuterium scrambling was observed between the carbon atoms derived from C-4 and C-5 of IPP or DMAPP, suggesting a completely stereoselective IPP isomerase or no significant activity of this enzyme. The C-3 deuterium atom of [3,5,5,5-(2)H(4)]ME was preserved only in the DMAPP starter unit and was completely missing from all those derived from IPP. This finding, aided by the non-essential role of the IPP isomerase gene, suggests the presence in E. coli of two different routes towards IPP and DMAPP, starting from a common intermediate derived from MEP. PMID:10698701

  5. Development of inhibitors of the 2C-methyl-D-erythritol 4-phosphate (MEP) pathway enzymes as potential anti-infective agents.

    PubMed

    Masini, Tiziana; Hirsch, Anna K H

    2014-12-11

    Important pathogens such as Mycobacterium tuberculosis and Plasmodium falciparum, the causative agents of tuberculosis and malaria, respectively, and plants, utilize the 2C-methyl-D-erythritol 4-phosphate (MEP, 5) pathway for the biosynthesis of isopentenyl diphosphate (1) and dimethylallyl diphosphate (2), the universal precursors of isoprenoids, while humans exclusively utilize the alternative mevalonate pathway for the synthesis of 1 and 2. This distinct distribution, together with the fact that the MEP pathway is essential in numerous organisms, makes the enzymes of the MEP pathway attractive drug targets for the development of anti-infective agents and herbicides. Herein, we review the inhibitors reported over the past 2 years, in the context of the most important older developments and with a particular focus on the results obtained against enzymes of pathogenic organisms. We will also discuss new discoveries in terms of structural and mechanistic features, which can help to guide a rational development of inhibitors.

  6. Plasmodium IspD (2-C-Methyl-D-erythritol 4-Phosphate Cytidyltransferase), an Essential and Druggable Antimalarial Target

    PubMed Central

    Imlay, Leah S.; Armstrong, Christopher M.; Masters, Mary Clare; Li, Ting; Price, Kathryn E.; Edwards, Rachel L.; Mann, Katherine M.; Li, Lucy X.; Stallings, Christina L.; Berry, Neil G.; O’Neill, Paul M.; Odom, Audrey R.

    2015-01-01

    As resistance to current therapies spreads, novel antimalarials are urgently needed. In this work, we examine the potential for therapeutic intervention via the targeting of Plasmodium IspD (2-C-methyl-D-erythritol 4-phosphate cytidyltransferase), the second dedicated enzyme of the essential methylerythritol phosphate (MEP) pathway for isoprenoid biosynthesis. Enzymes of this pathway represent promising therapeutic targets because the pathway is not present in humans. The Malaria Box compound, MMV008138, inhibits Plasmodium falciparum growth, and PfIspD has been proposed as a candidate intracellular target. We find that PfIspD is the sole intracellular target of MMV008138 and characterize the mode of inhibition and target-based resistance, providing chemical validation of this target. Additionally, we find that the Pf ISPD genetic locus is refractory to disruption in malaria parasites, providing independent genetic validation for efforts targeting this enzyme. This work provides compelling support for IspD as a druggable target for the development of additional, much-needed antimalarial agents. PMID:26783558

  7. [Cloning and expression analysis of 2-C-methyl-D-erythritol 4-phosphate cytidylyltransferase gene in Tripterygium wilfordii].

    PubMed

    Tong, Yu-ru; Su, Ping; Zhang, Meng; Zhao, Yu-jun; Wang, Xiu-juan; Gao, Wei; Huang, Lu-qi

    2015-11-01

    To clone the 2-C-methyl-D-erythritol 4-phosphate cytidylyltransferase (TwMCT) full length cDNA from Tripterygium wilfordii, the specific primers were designed according to the transcriptome data and the LCPCR were carried out. After a series of bioinformatics analysis on the TwMCT, the MeJA induced expression content were investigated by real-time fluorescence quantification polymerase chain reaction (RT-qPCR). The result showed that the full of TwMCTcDNA was 1 318 bp nucleotides encoding 311 amino acids. The molecular weight of the deduced TwMCT protein was about 34.14 kDa and the theoretical isoelectric point was 8.65. Result of the RT-qPCR analysis indicated that the content of TwMCT mRNA expression in T. wilfordii suspension cell was rising after treating with MeJA and reached the maximum in 24 h. Cloning and analyzing TwMCT gene from T. wilfordii provided gene element for studying the function and expression regulation of secondary metabolites.

  8. A structural and functional study on the 2-C-methyl-d-erythritol-4-phosphate cytidyltransferase (IspD) from Bacillus subtilis

    PubMed Central

    Jin, Yun; Liu, Zhongchuan; Li, Yanjie; Liu, Weifeng; Tao, Yong; Wang, Ganggang

    2016-01-01

    2-C-Methyl-D-erythritol-4-phosphate cytidyltransferase (IspD) is an essential enzyme in the mevalonate-independent pathway of isoprenoid biosynthesis. This enzyme catalyzes 2-C-Methyl-d-erythritol 4-phosphate (MEP) and cytosine triphosphate (CTP) to 4-diphosphocytidyl-2-C-methyl-d-erythritol (CDPME) and inorganic pyrophosphate (PPi). Bacillus subtilis was a kind of excellent isoprene producer. However, the studies on the key enzymes of MEP pathway in B. subtilis were still absent. In this work, the crystal structures of IspD and IspD complexed with CTP from B.subtilis were determined. For the first time, the intact P-loop was observed in the apo structure of IspD enzyme. Structural comparisons revealed that the concerted movements of the P-loop and loops close to the active site were essential in the reaction catalyzed by IspD. Meanwhile, kinetic analysis showed that the CTP hydrolytic activity of IspD from B.subtilis was over two times higher than that from Escherichia coli. These results will be useful for future target-based screening of potential inhibitors and the metabolic engineering for isoprenoid biosynthesis. PMID:27821871

  9. The Plastidial 2-C-Methyl-d-Erythritol 4-Phosphate Pathway Provides the Isoprenyl Moiety for Protein Geranylgeranylation in Tobacco BY-2 Cells[C][W

    PubMed Central

    Gerber, Esther; Hemmerlin, Andréa; Hartmann, Michael; Heintz, Dimitri; Hartmann, Marie-Andrée; Mutterer, Jérôme; Rodríguez-Concepción, Manuel; Boronat, Albert; Van Dorsselaer, Alain; Rohmer, Michel; Crowell, Dring N.; Bach, Thomas J.

    2009-01-01

    Protein farnesylation and geranylgeranylation are important posttranslational modifications in eukaryotic cells. We visualized in transformed Nicotiana tabacum Bright Yellow-2 (BY-2) cells the geranylgeranylation and plasma membrane localization of GFP-BD-CVIL, which consists of green fluorescent protein (GFP) fused to the C-terminal polybasic domain (BD) and CVIL isoprenylation motif from the Oryza sativa calmodulin, CaM61. Treatment with fosmidomycin (Fos) or oxoclomazone (OC), inhibitors of the plastidial 2-C-methyl-d-erythritol 4-phosphate (MEP) pathway, caused mislocalization of the protein to the nucleus, whereas treatment with mevinolin, an inhibitor of the cytosolic mevalonate pathway, did not. The nuclear localization of GFP-BD-CVIL in the presence of MEP pathway inhibitors was completely reversed by all-trans-geranylgeraniol (GGol). Furthermore, 1-deoxy-d-xylulose (DX) reversed the effects of OC, but not Fos, consistent with the hypothesis that OC blocks 1-deoxy-d-xylulose 5-phosphate synthesis, whereas Fos inhibits its conversion to 2-C-methyl-d-erythritol 4-phosphate. By contrast, GGol and DX did not rescue the nuclear mislocalization of GFP-BD-CVIL in the presence of a protein geranylgeranyltransferase type 1 inhibitor. Thus, the MEP pathway has an essential role in geranylgeranyl diphosphate (GGPP) biosynthesis and protein geranylgeranylation in BY-2 cells. GFP-BD-CVIL is a versatile tool for identifying pharmaceuticals and herbicides that interfere either with GGPP biosynthesis or with protein geranylgeranylation. PMID:19136647

  10. Kinetic analysis of Escherichia coli 2-C-methyl-D-erythritol-4-phosphate cytidyltransferase, wild type and mutants, reveals roles of active site amino acids.

    PubMed

    Richard, Stéphane B; Lillo, Antonietta M; Tetzlaff, Charles N; Bowman, Marianne E; Noel, Joseph P; Cane, David E

    2004-09-28

    Escherichia coli 2-C-methyl-D-erythritol-4-phosphate cytidyltransferase (YgbP or IspD) catalyzes the conversion of 2-C-methyl-D-erythritol 4-phosphate (MEP) and cytidine triphosphate (CTP) to 4-diphosphocytidyl-2-C-methylerythritol (CDPME). Pulse chase experiments established that the reaction involves an ordered sequential mechanism with mandatory initial binding of CTP. On the basis of analysis of the previously reported crystal structures of apo-YgbP as well as YgbP complexed with both CTP.Mg(2+) and CDPME.Mg(2+) [Richard, S. B., Bowman, M. E., Kwiatkowski, W., Kang, I., Chow, C., Lillo, A. M., Cane, D. E., and Noel, J. P. (2001) Nat. Struct. Biol. 8, 641-648], a group of active site residues were selected for site-directed mutagenesis and steady-state kinetic analysis. Both Lys27 and Lys213 were shown to be essential to catalytic activity, consistent with their proposed role in stabilization of a pentacoordinate phosphate transition state resulting from in-line attack of the MEP phosphate on the alpha-phosphate of CTP. In addition, Thr140, Arg109, Asp106, and Thr165 were all shown to play critical roles in the binding and proper orientation of the MEP substrate.

  11. Escherichia coli engineered to synthesize isopentenyl diphosphate and dimethylallyl diphosphate from mevalonate: a novel system for the genetic analysis of the 2-C-methyl-d-erythritol 4-phosphate pathway for isoprenoid biosynthesis.

    PubMed Central

    Campos, N; Rodríguez-Concepción, M; Sauret-Güeto, S; Gallego, F; Lois, L M; Boronat, A

    2001-01-01

    Isopentenyl diphosphate (IPP) and its isomer dimethylallyl diphosphate (DMAPP) constitute the basic building block of isoprenoids, a family of compounds that is extraordinarily diverse in structure and function. IPP and DMAPP can be synthesized by two independent pathways: the mevalonate pathway and the recently discovered 2-C-methyl-d-erythritol 4-phosphate (MEP) pathway. Although the MEP pathway is essential in most eubacteria, algae and plants and has enormous biotechnological interest, only some of its steps have been determined. We devised a system suitable for the genetic analysis of the MEP pathway in Escherichia coli. A synthetic operon coding for yeast 5-diphosphomevalonate decarboxylase, human 5-phosphomevalonate kinase, yeast mevalonate kinase and E. coli isopentenyl diphosphate isomerase was incorporated in the chromosome of this bacterium. The expression of this operon allowed the synthesis of IPP and DMAPP from mevalonate added exogenously and complementation of lethal mutants of the MEP pathway. We used this system to show that the ygbP, ychB and ygbB genes are essential in E. coli and that the steps catalysed by the products of these genes belong to the trunk line of the MEP pathway. PMID:11115399

  12. Chemoenzymatic synthesis of 4-diphosphocytidyl-2-C-methyl-D-erythritol: A substrate for IspE.

    PubMed

    Narayanasamy, Prabagaran; Eoh, Hyungjin; Crick, Dean C

    2008-07-21

    Enantiomerically pure 2-C-methyl-D-erythritol 4-phosphate 1 (MEP) is synthesized from 1,2-O-isopropylidene-α-D-xylofuranose via facile benzylation in good yield. Subsequently, 1 is used for enzymatic synthesis of 4-diphosphocytidyl-2-C-methyl-D-erythritol 2 (CDP-ME) using 4-diphosphocytidyl-2-C-methyl-D-erythritol synthase (IspD). The chemoenzymatically synthesized 2 can be used as substrate for assay of IspE and for high throughput screening to identify IspE inhibitors.

  13. Studies on the nonmevalonate pathway of terpene biosynthesis. The role of 2C-methyl-D-erythritol 2,4-cyclodiphosphate in plants.

    PubMed

    Fellermeier, M; Raschke, M; Sagner, S; Wungsintaweekul, J; Schuhr, C A; Hecht, S; Kis, K; Radykewicz, T; Adam, P; Rohdich, F; Eisenreich, W; Bacher, A; Arigoni, D; Zenk, M H

    2001-12-01

    2C-methyl-D-erythritol 2,4-cyclodiphosphate was recently shown to be formed from 2C-methyl-D-erythritol 4-phosphate by the consecutive action of IspD, IspE, and IspF proteins in the nonmevalonate pathway of terpenoid biosynthesis. To complement previous work with radiolabelled precursors, we have now demonstrated that [U-13C5]2C-methyl-D-erythritol 4-phosphate affords [U-13C5]2C-methyl-D-erythritol 2,4-cyclodiphosphate in isolated chromoplasts of Capsicum annuum and Narcissus pseudonarcissus. Moreover, chromoplasts are shown to efficiently convert 2C-methyl-D-erythritol 4-phosphate as well as 2C-methyl-D-erythritol 2,4-cyclodiphosphate into the carotene precursor phytoene. The bulk of the kinetic data collected in competition experiments with radiolabeled substrates is consistent with the notion that the cyclodiphosphate is an obligatory intermediate in the nonmevalonate pathway to terpenes. Studies with [2,2'-13C2]2C-methyl-D-erythritol 2,4-cyclodiphosphate afforded phytoene characterized by pairs of jointly transferred 13C atoms in the positions 17/1, 18/5, 19/9, and 20/13 and, at a lower abundance, in positions 16/1, 4/5, 8/9, and 12/13. A detailed scheme is presented for correlating the observed partial scrambling of label with the known lack of fidelity of the isopentenyl diphosphate/dimethylethyl diphosphate isomerase.

  14. A spectrophotometric assay for the determination of 4-diphosphocytidyl-2-C-methyl-D-erythritol kinase activity.

    PubMed

    Bernal, Cristobal; Mendez, Eva; Terencio, José; Boronat, Albert; Imperial, Santiago

    2005-05-15

    We report an assay for the determination of the activity of 4-diphosphocytidyl-2-C-methyl-D-erythritol kinase, the enzyme which catalyzes the fourth reaction step of the 2-C-methyl-D-erythritol 4-phosphate pathway for the synthesis of isoprenoids, which is based on the spectrophotometrical determination of adenosine 5'-diphosphate using pyruvate kinase and L-lactate dehydrogenase as auxiliary enzymes. This method can be adapted to microtiter plates, can be automated, and because of its simplicity and speed can be useful for the functional characterization of the enzyme and for the screening of inhibitors with potential antibiotic or antimalarial action.

  15. 2C-Methyl- D- erythritol 2,4-cyclodiphosphate synthase from Stevia rebaudiana Bertoni is a functional gene.

    PubMed

    Kumar, Hitesh; Singh, Kashmir; Kumar, Sanjay

    2012-12-01

    Stevia [Stevia rebaudiana (Bertoni)] is a perennial herb which accumulates sweet diterpenoid steviol glycosides (SGs) in its leaf tissue. SGs are synthesized by 2C-methyl-D-erythritol 4-phosphate (MEP) pathway. Of the various enzymes of the MEP pathway, 2C-methyl-D-erythritol 2,4-cyclodiphosphate synthase (MDS) (encoded by MDS) catalyzes the cyclization of 4-(cytidine 5' diphospho)-2C-methyl-D-erythritol 2-phosphate into 2C-methyl-D-erythritol 2,4-cyclodiphosphate. Complementation of the MDS knockout mutant strain of Escherichia coli, EB370 with putative MDS of stevia (SrMDS) rescued the lethal mutant, suggesting SrMDS to be a functional gene. Experiments conducted in plant growth chamber and in the field suggested SrMDS to be a light regulated gene. Indole 3-acetic acid (IAA; 50, 100 μM) down-regulated the expression of SrMDS at 4 h of the treatment, whereas, abscisic acid did not modulate its expression. A high expression of SrMDS was observed during the light hours of the day as compared to the dark hours. The present work established functionality of SrMDS and showed the role of light and IAA in regulating expression of SrMDS.

  16. Expression and characterization of soluble 4-diphosphocytidyl-2-C-methyl-D-erythritol kinase from bacterial pathogens.

    PubMed

    Eoh, Hyungjin; Narayanasamy, Prabagaran; Brown, Amanda C; Parish, Tanya; Brennan, Patrick J; Crick, Dean C

    2009-12-24

    Many bacterial pathogens utilize the 2-C-methyl-D-erythritol 4-phosphate pathway for biosynthesizing isoprenoid precursors, a pathway that is vital for bacterial survival and absent from human cells, providing a potential source of drug targets. However, the characterization of 4-diphosphocytidyl-2-C-methyl-D-erythritol (CDP-ME) kinase (IspE) has been hindered due to a lack of enantiopure CDP-ME and difficulty in obtaining pure IspE. Here, enantiopure CDP-ME was chemically synthesized and recombinant IspE from bacterial pathogens were purified and characterized. Although gene disruption was not possible in Mycobacterium tuberculosis, IspE is essential in Mycobacterium smegmatis. The biochemical and kinetic characteristics of IspE provide the basis for development of a high throughput screen and structural characterization.

  17. Crystal structure of 4-diphosphocytidyl-2-C-methyl-D-erythritol kinase (IspE) from Mycobacterium tuberculosis.

    PubMed

    Shan, Shan; Chen, Xuehui; Liu, Ting; Zhao, Hanchao; Rao, Zihe; Lou, Zhiyong

    2011-05-01

    Isoprenoid precursors, which are a large group of natural products and play key roles in many biological pathways, can only be biosynthesized by the 2-C-methyl-d-erythritol 4-phosphate pathway in Mycobacterium tuberculosis. The 4-diphosphocytidyl-2-C-methyl-d-erythritol kinase (IspE), which is an essential enzyme in the isoprenoid precursor biosynthesis pathway, catalyzes ATP-dependent phosphorylation of 4-diphosphocytidyl-2-C-methyl-d-erythritol (CDP-ME) to 4-diphosphocytidyl-2C-methyl-d-erythritol-2-phosphate and plays a crucial role in M. tuberculosis survival. Therefore, IspE is characterized as an attractive and potential target for antimicrobial drug discovery. However, no experimental structure of M. tuberculosis IspE has been reported, which has hindered our understanding of its structural details and mechanism of action. Here, we report the expression and purification of fully active full-length M. tuberculosis IspE and solve the high-resolution crystal structures of IspE alone and in complex with either the substrate CDP-ME or nonhydrolyzable ATP analog or ADP. The structures present a characteristic galactose/homoserine/mevalonate/phosphomevalonate kinase superfamily α/β-fold with a catalytic center located in a cleft between 2 domains and display clear substrate and ATP binding pockets. Our results also indicate distinct differences in ligand binding of M. tuberculosis IspE with other reported IspEs. Combined with the results of mutagenesis and enzymatic studies, our results provide useful information on the structural basis of IspE for future anti-M. tuberculosis drug discovery targeting this kinase.

  18. Crystallization and preliminary X-ray analysis of 4-diphosphocytidyl-2-C-methyl-D-erythritol kinase (IspE) from Mycobacterium tuberculosis.

    PubMed

    Shan, Shan; Chen, Xuehui

    2011-07-01

    The 4-diphosphocytidyl-2-C-methyl-D-erythritol kinase (IspE) from Mycobacterium tuberculosis, an enzyme from the 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway, is crucial and essential for the survival of this pathogenic bacterium. IspE catalyzes the conversion of 4-diphosphocytidyl-2-C-methyl-D-erythritol (CDP-ME) to 4-diphosphocytidyl-2-C-methyl-D-erythritol 2-phosphate (CDP-ME2P) in an ATP-dependent manner. Solving the crystal structure of M. tuberculosis IspE will shed light on its structural details and mechanism of action and may provide the basis for the future design of drugs for the treatment of multidrug-resistant and extremely drug-resistant M. tuberculosis strains. Recombinant M. tuberculosis IspE was crystallized at 291 K using NaCl or Li2SO4 as a precipitant. A 2.1 Å resolution native data set was collected from a single flash-cooled crystal (100 K) belonging to space group P2(1)2(1)2(1), with unit-cell parameters a=52.5, b=72.3, c=107.3 Å. One molecule was assumed per asymmetric unit, which gives a Matthews coefficient of 3.4 Å3 Da(-1) with 63% solvent content.

  19. Glycosides of 2-C-methyl-D-erythritol from the fruits of anise, coriander and cumin.

    PubMed

    Kitajima, Junichi; Ishikawa, Toru; Fujimatu, Eiko; Kondho, Kyoko; Takayanagi, Tomomi

    2003-01-01

    Eight glycosides of 2-C-methyl-D-erythritol (1) were isolated from the fruit of anise, and their structures were clarified as 1-O-beta-D-glucopyranoside, 3-O-beta-D-glucopyranoside, 4-O-beta-D-glucopyranoside, 1-O-beta-D-fructofuranoside, 3-O-beta-D-fructofuranoside, 4-O-beta-D-fructofuranoside, 1-O-beta-D-(6-O-4-hydroxybenzoyl)-glucopyranoside and 1-O-beta-D-(6-O-4-methoxybenzoyl)-glucopyranoside of 2-C-methyl-D-erythritol (2-9), respectively. Furthermore, 2 and 4 were isolated from the fruit of coriander, and 2, 3 and 4 were isolated from the fruit of cumin. Though the phosphate of 1 was known to be one of the first precursors of isoprenoids in the non-mevalonate pathway, and 1 is considered to be a common constituent in Umbelliferous plants, the glycosides of 1 are found for the first time.

  20. Biosynthesis of terpenoids. 2C-Methyl-D-erythritol 2,4-cyclodiphosphate synthase (IspF) from Plasmodium falciparum.

    PubMed

    Rohdich, F; Eisenreich, W; Wungsintaweekul, J; Hecht, S; Schuhr, C A; Bacher, A

    2001-06-01

    The putative catalytic domain of an open reading frame from Plasmodium falciparum with similarity to the ispF gene of Escherichia coli specifying 2C-methyl-D-erythritol 2,4-cyclodiphosphate synthase was expressed in a recombinant E. coli strain. The recombinant protein was purified to homogeneity and was found to catalyze the formation of 2C-methyl-D-erythritol 2,4-cyclodiphosphate from 4-diphosphocytidyl-2C-methyl-D-erythritol 2-phosphate at a rate of 4.3 micromol x mg(-1) x min(-1). At lower rates, the recombinant protein catalyzes the formation of 2-phospho-2C-methyl-D-erythritol 3,4-cyclophosphate from 4-diphosphocytidyl-2C-methyl-D-erythritol 2-phosphate and the formation of 2C-methyl-D-erythritol 3,4-cyclophosphate from 4-diphosphocytidyl-2C-methyl-D-erythritol. Divalent metal ions such as magnesium or manganese are required for catalytic activity. The enzyme has a pH optimum at pH 7.0. Recombinant expression of the full-length open reading frame afforded insoluble protein that could not be folded in vitro. The enzyme is a potential target for antimalarial drugs directed at the nonmevalonate pathway of isoprenoid biosynthesis.

  1. Biosynthesis of terpenoids: YgbB protein converts 4-diphosphocytidyl-2C-methyl-d-erythritol 2-phosphate to 2C-methyl-d-erythritol 2,4-cyclodiphosphate

    PubMed Central

    Herz, Stefan; Wungsintaweekul, Juraithip; Schuhr, Christoph A.; Hecht, Stefan; Lüttgen, Holger; Sagner, Sylvia; Fellermeier, Monika; Eisenreich, Wolfgang; Zenk, Meinhart H.; Bacher, Adelbert; Rohdich, Felix

    2000-01-01

    In many microorganisms, the putative orthologs of the Escherichia coli ygbB gene are tightly linked or fused to putative orthologs of ygbP, which has been shown earlier to be involved in terpenoid biosynthesis. The ygbB gene of E. coli was expressed in a recombinant E. coli strain and was shown to direct the synthesis of a soluble, 17-kDa polypeptide. The recombinant protein was found to convert 4-diphosphocytidyl-2C-methyl-d-erythritol 2-phosphate into 2C-methyl-d-erythritol 2,4-cyclodiphosphate and CMP. The structure of the reaction product was established by NMR spectroscopy using 13C-labeled substrate samples. The enzyme-catalyzed reaction requires Mn2+ or Mg2+ but no other cofactors. Radioactivity from [2-14C]2C-methyl-d-erythritol 2,4-cyclodiphosphate was diverted efficiently to carotenoids by isolated chromoplasts from Capsicum annuum and, thus, was established as an intermediate in the deoxyxylulose phosphate pathway of isoprenoid biosynthesis. YgbB protein also was found to convert 4-diphosphocytidyl-2C-methyl-d-erythritol into 2C-methyl-d-erythritol 3,4-cyclophosphate. This compound does not serve as substrate for the formation of carotenoids by isolated chromoplasts and is assumed to be an in vitro product without metabolic relevance. PMID:10694574

  2. Biosynthesis of terpenoids: YgbB protein converts 4-diphosphocytidyl-2C-methyl-D-erythritol 2-phosphate to 2C-methyl-D-erythritol 2,4-cyclodiphosphate.

    PubMed

    Herz, S; Wungsintaweekul, J; Schuhr, C A; Hecht, S; Luttgen, H; Sagner, S; Fellermeier, M; Eisenreich, W; Zenk, M H; Bacher, A; Rohdich, F

    2000-03-14

    In many microorganisms, the putative orthologs of the Escherichia coli ygbB gene are tightly linked or fused to putative orthologs of ygbP, which has been shown earlier to be involved in terpenoid biosynthesis. The ygbB gene of E. coli was expressed in a recombinant E. coli strain and was shown to direct the synthesis of a soluble, 17-kDa polypeptide. The recombinant protein was found to convert 4-diphosphocytidyl-2C-methyl-D-erythritol 2-phosphate into 2C-methyl-D-erythritol 2,4-cyclodiphosphate and CMP. The structure of the reaction product was established by NMR spectroscopy using (13)C-labeled substrate samples. The enzyme-catalyzed reaction requires Mn(2+) or Mg(2+) but no other cofactors. Radioactivity from [2-(14)C]2C-methyl-D-erythritol 2,4-cyclodiphosphate was diverted efficiently to carotenoids by isolated chromoplasts from Capsicum annuum and, thus, was established as an intermediate in the deoxyxylulose phosphate pathway of isoprenoid biosynthesis. YgbB protein also was found to convert 4-diphosphocytidyl-2C-methyl-D-erythritol into 2C-methyl-D-erythritol 3,4-cyclophosphate. This compound does not serve as substrate for the formation of carotenoids by isolated chromoplasts and is assumed to be an in vitro product without metabolic relevance.

  3. Biosynthesis of isoprenoids: crystal structure of 4-diphosphocytidyl-2C-methyl-D-erythritol kinase.

    PubMed

    Miallau, Linda; Alphey, Magnus S; Kemp, Lauris E; Leonard, Gordon A; McSweeney, Sean M; Hecht, Stefan; Bacher, Adelbert; Eisenreich, Wolfgang; Rohdich, Felix; Hunter, William N

    2003-08-05

    4-Diphosphocytidyl-2C-methyl-d-erythritol kinase, an essential enzyme in the nonmevalonate pathway of isopentenyl diphosphate and dimethylallyl diphosphate biosynthesis, catalyzes the single ATP-dependent phosphorylation stage affording 4-diphosphocytidyl-2C-methyl-d-erythritol-2-phosphate. The 2-A resolution crystal structure of the Escherichia coli enzyme in a ternary complex with substrate and a nonhydrolyzable ATP analogue reveals the molecular determinants of specificity and catalysis. The enzyme subunit displays the alpha/beta fold characteristic of the galactose kinase/homoserine kinase/mevalonate kinase/phosphomevalonate kinase superfamily, arranged into cofactor and substrate-binding domains with the catalytic center positioned in a deep cleft between domains. Comparisons with related members of this superfamily indicate that the core regions of each domain are conserved, whereas there are significant differences in the substrate-binding pockets. The nonmevalonate pathway is essential in many microbial pathogens and distinct from the mevalonate pathway used by mammals. The high degree of sequence conservation of the enzyme across bacterial species suggests similarities in structure, specificity, and mechanism. Our model therefore provides an accurate template to facilitate the structure-based design of broad-spectrum antimicrobial agents.

  4. Characterization of Aquifex aeolicus 4-diphosphocytidyl-2C-methyl-d-erythritol kinase - ligand recognition in a template for antimicrobial drug discovery.

    PubMed

    Sgraja, Tanja; Alphey, Magnus S; Ghilagaber, Stephanos; Marquez, Rudi; Robertson, Murray N; Hemmings, Jennifer L; Lauw, Susan; Rohdich, Felix; Bacher, Adelbert; Eisenreich, Wolfgang; Illarionova, Victoria; Hunter, William N

    2008-06-01

    4-Diphosphocytidyl-2C-methyl-D-erythritol kinase (IspE) catalyses the ATP-dependent conversion of 4-diphosphocytidyl-2C-methyl-D-erythritol (CDPME) to 4-diphosphocytidyl-2C-methyl-d-erythritol 2-phosphate with the release of ADP. This reaction occurs in the non-mevalonate pathway of isoprenoid precursor biosynthesis and because it is essential in important microbial pathogens and absent from mammals it represents a potential target for anti-infective drugs. We set out to characterize the biochemical properties, determinants of molecular recognition and reactivity of IspE and report the cloning and purification of recombinant Aquifex aeolicus IspE (AaIspE), kinetic data, metal ion, temperature and pH dependence, crystallization and structure determination of the enzyme in complex with CDP, CDPME and ADP. In addition, 4-fluoro-3,5-dihydroxy-4-methylpent-1-enylphosphonic acid (compound 1) was designed to mimic a fragment of the substrate, a synthetic route to 1 was elucidated and the complex structure determined. Surprisingly, this ligand occupies the binding site for the ATP alpha-phosphate not the binding site for the methyl-D-erythritol moiety of CDPME. Gel filtration and analytical ultracentrifugation indicate that AaIspE is a monomer in solution. The enzyme displays the characteristic alpha/beta galacto-homoserine-mevalonate-phosphomevalonate kinase fold, with the catalytic centre positioned in a deep cleft between the ATP- and CDPME-binding domains. Comparisons indicate a high degree of sequence conservation on the IspE active site across bacterial species, similarities in structure, specificity of substrate recognition and mechanism. The biochemical characterization, attainment of well-ordered and reproducible crystals and the models resulting from the analyses provide reagents and templates to support the structure-based design of broad-spectrum antimicrobial agents.

  5. A triclinic crystal form of Escherichia coli 4-diphosphocytidyl-2C-methyl-D-erythritol kinase and reassessment of the quaternary structure.

    PubMed

    Kalinowska-Tłuścik, Justyna; Miallau, Linda; Gabrielsen, Mads; Leonard, Gordon A; McSweeney, Sean M; Hunter, William N

    2010-03-01

    4-Diphosphocytidyl-2C-methyl-D-erythritol kinase (IspE; EC 2.7.1.148) contributes to the 1-deoxy-D-xylulose 5-phosphate or mevalonate-independent biosynthetic pathway that produces the isomers isopentenyl diphosphate and dimethylallyl diphosphate. These five-carbon compounds are the fundamental building blocks for the biosynthesis of isoprenoids. The mevalonate-independent pathway does not occur in humans, but is present and has been shown to be essential in many dangerous pathogens, i.e. Plasmodium species, which cause malaria, and gram-negative bacteria. Thus, the enzymes involved in this pathway have attracted attention as potential drug targets. IspE produces 4-diphosphosphocytidyl-2C-methyl-D-erythritol 2-phosphate by ATP-dependent phosphorylation of 4-diphosphocytidyl-2C-methyl-D-erythritol. A triclinic crystal structure of the Escherichia coli IspE-ADP complex with two molecules in the asymmetric unit was determined at 2 A resolution and compared with a monoclinic crystal form of a ternary complex of E. coli IspE also with two molecules in the asymmetric unit. The molecular packing is different in the two forms. In the asymmetric unit of the triclinic crystal form the substrate-binding sites of IspE are occluded by structural elements of the partner, suggesting that the ;triclinic dimer' is an artefact of the crystal lattice. The surface area of interaction in the triclinic form is almost double that observed in the monoclinic form, implying that the dimeric assembly in the monoclinic form may also be an artifact of crystallization.

  6. Crystal structure of 4-(cytidine 5'-diphospho)-2-C-methyl-D-erythritol kinase, an enzyme in the non-mevalonate pathway of isoprenoid synthesis.

    PubMed

    Wada, Takashi; Kuzuyama, Tomohisa; Satoh, Shinya; Kuramitsu, Seiki; Yokoyama, Shigeyuki; Unzai, Satoru; Tame, Jeremy R H; Park, Sam-Yong

    2003-08-08

    The crystal structure of the enzyme 4-(cytidine 5'-diphospho)-2-C-methyl-D-erythritol (CDP-ME) kinase from the thermophilic bacterium Thermus thermophilus HB8 has been determined at 1.7-A resolution. This enzyme catalyzes phosphorylation of the 2-hydroxyl group of CDP-ME, the fourth step of the non-mevalonate pathway, which is essential for isoprenoid biosynthesis in several pathogenic microorganisms. Since this pathway is absent in humans, it is an important target for the development of novel antimicrobial compounds. The structure of the enzyme is similar to the structures of mevalonate kinase and homoserine kinase, members of the GHMP superfamily. Lys8 and Asp125 are active site residues in mevalonate kinase that also appear to play a catalytic role in CDP-ME kinase. Both the mevalonate and the non-mevalonate pathways therefore involve closely related kinases with similar mechanisms. Assaying the enzyme showed that CDP-ME kinase will phosphorylate CDP-ME but not 4-(uridine 5'-diphospho)-2-C-methyl-D-erythritol, indicating the substrate pyrimidine moiety is involved in important interactions with the enzyme.

  7. [Screening of potential antibiotics, inhibitors of the nonmevalonate pathway of isoprenoid biosynthesis--2-C-methyl-D-erythritol-2,4-cyclodiphosphate derivatives].

    PubMed

    Ershov, Iu V; Mazikin, K V; Ostrovskiĭ, D N

    2010-01-01

    The recently discovered nonmevalonate pathway of isoprenoid biosynthesis is a prospective target in screening of new antibiotics. Because of the absence of the pathway in the animal cells, the specific inhibitors of the pathway will be a new class of antibiotics against many pathogens (which cause, e.g., malaria, tuberculosis, etc), combining high efficiency and low toxicity. Several derivatives of 2-C-methyl-D-erythritol-2,4-cyclodiphosphate (MEC) were synthesized. 4-Phospho-methyl-D-erythritol-1,2-cyclophosphate, benzyl ether and benzyliden derivative of MEC inhibited the 14C-MEC incorporation into isoprenoids of chromoplasts from red pepper with IC50 of 1.7-5 MM. Some inhibition (about 10%) was also observed with the use of dimethyl ether and isopropyliden derivative of MEC.

  8. Identification of novel small molecule inhibitors of 4-diphosphocytidyl-2-C-methyl-D-erythritol (CDP-ME) kinase of Gram-negative bacteria.

    PubMed

    Tang, M; Odejinmi, S I; Allette, Y M; Vankayalapati, H; Lai, K

    2011-10-01

    The biosyntheses of isoprenoids is essential for the survival in all living organisms, and requires one of the two biochemical pathways: (a) Mevalonate (MVA) Pathway or (b) Methylerythritol Phosphate (MEP) Pathway. The latter pathway, which is used by all Gram-negative bacteria, some Gram-positive bacteria and a few apicomplexan protozoa, provides an attractive target for the development of new antimicrobials because of its absence in humans. In this report, we describe two different approaches that we used to identify novel small molecule inhibitors of Escherichia coli and Yersinia pestis 4-diphosphocytidyl-2-C-methyl D-erythritol (CDP-ME) kinases, key enzymes of the MEP pathway encoded by the E. coli ispE and Y. pestisipk genes, respectively. In the first approach, we explored existing inhibitors of the GHMP kinases while in the second approach; we performed computational high-throughput screening of compound libraries by targeting the CDP-ME binding site of the two bacterial enzymes. From the first approach, we identified two compounds with 6-(benzylthio)-2-(2-hydroxyphenyl)-4-oxo-3,4-dihydro-2H-1,3-thiazine-5-carbonitrile and (Z)-3-methyl-4-((5-phenylfuran-2-yl)methylene)isoxazol-5(4H)-one scaffolds which inhibited E. coli CDP-ME kinase in vitro. We then performed substructure search and docking experiments based on these two scaffolds and identified twenty three analogs for structure-activity relationship (SAR) studies. Three new compounds from the isoxazol-5(4H)-one series have shown inhibitory activities against E. coli and Y. pestis CDP-ME kinases with the IC(50) values ranging from 7 to 13 μM. The second approach by computational high-throughput screening (HTS) of two million drug-like compounds yielded two compounds with benzenesulfonamide and acetamide moieties which, at a concentration of 20 μM, inhibited 80% and 65%, respectively, of control CDP-ME kinase activity.

  9. [Properties of 2-C-methyl-D-erythritol 2,4-cyclopyrophosphate--an intermediate in the non-mevalonate isoprenoid biosynthesis].

    PubMed

    Ostrovskiĭ, D N; Demina, G P; Deriabina, Iu I; Goncharenko, A V; Eberl, M; Shumaev, K B; Shashkov, A S

    2003-01-01

    Extraction and purification from the biomass of Corynebacterium ammoniagenes of 2-C-methyl-D-erhythritol 2,4-cyclopyrophosphate (MEC) was associated with its spontaneous transformation into a number of derivatives (which was due to pyrophosphate bond lability and the formation of complexes with metals). These derivatives included 1,2-cyclophospho-4-phosphate, 2,4-diphosphate, 2,3-cyclophosphate, 1,4-diphosphate, and 3,5-diphosphate (identified by 1H, 31P, and 13C NMR spectroscopy) and accounted for about 10% MEC. When added to a solution of DNA in the presence of the Fenton reagent, MEC prevented DNA decomposition. In addition, MEC slowed down the interaction of the reagent with tempol radicals, which indicates that complexation of ferrous ions by MEC attenuates their ability to catalyze the formation of hydroxyl radicals from hydrogen peroxide. In the presence of 0.23 mM MEC, the rate of respiration of rat liver mitochondria increased 1.8 times. At 0.1-1.0 mM, MEC activated in vitro proliferation of human Vgamma9 T-cells. It is suggested that MEC acts as an endogenous stabilizing agent for bacterial cells subjected to oxidative stress and as an immunomodulator for eukaryotic hosts.

  10. A double mutation of Escherichia coli 2C-methyl-d-erythritol-2,4-cyclodiphosphate synthase disrupts six hydrogen bonds with, yet fails to prevent binding of, an isoprenoid diphosphate

    PubMed Central

    Sgraja, Tanja; Kemp, Lauris E.; Ramsden, Nicola; Hunter, William N.

    2005-01-01

    The essential enzyme 2C-methyl-d-erythritol-2,4-cyclodiphosphate (MECP) synthase, found in most eubacteria and the apicomplexan parasites, participates in isoprenoid-precursor biosynthesis and is a validated target for the development of broad-spectrum antimicrobial drugs. The structure and mechanism of the enzyme have been elucidated and the recent exciting finding that the enzyme actually binds diphosphate-containing isoprenoids at the interface formed by the three subunits that constitute the active protein suggests the possibility of feedback regulation of MECP synthase. To investigate such a possibility, a form of the enzyme was sought that did not bind these ligands but which would retain the quaternary structure necessary to create the active site. Two amino acids, Arg142 and Glu144, in Escherichia coli MECP synthase were identified as contributing to ligand binding. Glu144 interacts directly with Arg142 and positions the basic residue to form two hydrogen bonds with the terminal phosphate group of the isoprenoid diphosphate ligand. This association occurs at the trimer interface and three of these arginines interact with the ligand phosphate group. A dual mutation was designed (Arg142 to methionine and Glu144 to leucine) to disrupt the electrostatic attractions between the enzyme and the phosphate group to investigate whether an enzyme without isoprenoid diphosphate could be obtained. A low-resolution crystal structure of the mutated MECP synthase Met142/Leu144 revealed that geranyl diphosphate was retained despite the removal of six hydrogen bonds normally formed with the enzyme. This indicates that these two hydrophilic residues on the surface of the enzyme are not major determinants of isoprenoid binding at the trimer interface but rather that hydrophobic interactions between the hydrocarbon tail and the core of the enzyme trimer dominate ligand binding. PMID:16511114

  11. Structure of 2C-methyl-D-erythritol-2,4-cyclodiphosphate synthase from Shewanella oneidensis at 1.6 A: identification of farnesyl pyrophosphate trapped in a hydrophobic cavity.

    PubMed

    Ni, Shuisong; Robinson, Howard; Marsing, Gregory C; Bussiere, Dirksen E; Kennedy, Michael A

    2004-11-01

    Isopentenyl pyrophosphate (IPP) is a universal building block for the ubiquitous isoprenoids that are essential to all organisms. The enzymes of the non-mevalonate pathway for IPP synthesis, which is unique to many pathogenic bacteria, have recently been explored as targets for antibiotic development. Several crystal structures of 2C-methyl-D-erythritol-2,4-cyclophosphate (MECDP) synthase, the fifth of seven enzymes involved in the non-mevalonate pathway for synthesis of IPP, have been reported; however, the composition of metal ions in the active site and the presence of a hydrophobic cavity along the non-crystallographic threefold symmetry axis has varied between the reported structures. Here, the structure of MEDCP from Shewanella oneidensis MR1 (SO3437) was determined to 1.6 A resolution in the absence of substrate. The presence of a zinc ion in the active-site cleft, tetrahedrally coordinated by two histidine side chains, an aspartic acid side chain and an ambiguous fourth ligand, was confirmed by zinc anomalous diffraction. Based on analysis of anomalous diffraction data and typical metal-to-ligand bond lengths, it was concluded that an octahedral sodium ion was 3.94 A from the zinc ion. A hydrophobic cavity was observed along the threefold non-crystallographic symmetry axis, filled by a well defined non-protein electron density that could be modeled as farnesyl pyrophosphate (FPP), a downstream product of IPP, suggesting a possible feedback mechanism for enzyme regulation. The high-resolution data clarified the FPP-binding mode compared with previously reported structures. Multiple sequence alignment indicated that the residues critical to the formation of the hydrophobic cavity and for coordinating the pyrophosphate group of FPP are present in the majority of MEDCP synthase enzymes, supporting the idea of a specialized biological function related to FPP binding in a subfamily of MEDCP synthase homologs.

  12. Structure of 2C-Methyl-D-erythritol-2,4-cyclodiphosphate Synthase from Shewanella oneidensis at 1.6 angstrom: Identification of Farnesyl pyrophosphate Trapped in a Hydrophobic Cavity

    SciTech Connect

    Ni, Shuisong; Robinson, Howard; Marsing, Gregory C.; Bussiere, Dirksen E.; Kennedy, Michael A.

    2004-11-01

    1. Introduction Enzymes in the non-mevalonate pathway for isoprenoid synthesis have gained recent attention because of their potential value as targets for antibiotic drug development. 2C-methyl-D-erythritol-2,4 cyclophosphate (MECDP) synthase is the fifth enzyme in the seven enzyme non-mevalonate pathway for synthesis of isopentenyl diphosphate. Four groups have published structures of MECDP synthase at resolutions varying from 1.6Å to 2.8Å, either in the presence or absence of substrate from Escherichia coli (Richard et al., 2002; Kemp et al., 2002; Steinbacher et al., 2002) or from Thermus thermophilus (Kishida et al., 2003). Among these structures, the protein always exists as a homotrimer either with a crystallographic or a non-crystallographic three-fold symmetry axis and an active site formed in a cleft between adjacent monomers. While the overall shape of the proteins is highly similar among these structures, each of the four reported structures contain different combinations of metal ions in the active site including a Zn2+ ion only (Steinbacher et al., 2002), a Mn2+ ion only (Richard et al., 2002), Zn2+ and Mn2+ ions (Kemp et al., 2002) or two Mg2+ ions (Kishida et al., 2003). Furthermore, two of the structures are reported to contain a hydrophobic channel along the three-fold symmetry axis that is capped by a cluster of three arginine side chains (one from each monomer) at one end of the cavity and a cluster of three glutamic acid side chains (one from each monomer) at the other side of the cavity. In a 1.8Å resolution structure, Kemp et al. (2002) reported a sulfate ion coordinated to the arginine cap and solvent trapped in a hydrophobic cavity. In a lower 2.8Å resolution structure, Richard et al. (2002) concluded that geranyl diphosphate, GPP, was most likely trapped by the arginine cap and hydrophobic cavity (Richard et al., 2002), however, the low resolution of the data together with the presence of the crystallographic symmetry axis prohibited a

  13. Feedback inhibition of deoxy-D-xylulose-5-phosphate synthase regulates the methylerythritol 4-phosphate pathway.

    PubMed

    Banerjee, Aparajita; Wu, Yan; Banerjee, Rahul; Li, Yue; Yan, Honggao; Sharkey, Thomas D

    2013-06-07

    The 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway leads to the biosynthesis of isopentenyl diphosphate (IDP) and dimethylallyl diphosphate (DMADP), the precursors for isoprene and higher isoprenoids. Isoprene has significant effects on atmospheric chemistry, whereas other isoprenoids have diverse roles ranging from various biological processes to applications in commercial uses. Understanding the metabolic regulation of the MEP pathway is important considering the numerous applications of this pathway. The 1-deoxy-D-xylulose-5-phosphate synthase (DXS) enzyme was cloned from Populus trichocarpa, and the recombinant protein (PtDXS) was purified from Escherichia coli. The steady-state kinetic parameters were measured by a coupled enzyme assay. An LC-MS/MS-based assay involving the direct quantification of the end product of the enzymatic reaction, 1-deoxy-D-xylulose 5-phosphate (DXP), was developed. The effect of different metabolites of the MEP pathway on PtDXS activity was tested. PtDXS was inhibited by IDP and DMADP. Both of these metabolites compete with thiamine pyrophosphate for binding with the enzyme. An atomic structural model of PtDXS in complex with thiamine pyrophosphate and Mg(2+) was built by homology modeling and refined by molecular dynamics simulations. The refined structure was used to model the binding of IDP and DMADP and indicated that IDP and DMADP might bind with the enzyme in a manner very similar to the binding of thiamine pyrophosphate. The feedback inhibition of PtDXS by IDP and DMADP constitutes an important mechanism of metabolic regulation of the MEP pathway and indicates that thiamine pyrophosphate-dependent enzymes may often be affected by IDP and DMADP.

  14. A mutant pyruvate dehydrogenase E1 subunit allows survival of Escherichia coli strains defective in 1-deoxy-D-xylulose 5-phosphate synthase.

    PubMed

    Sauret-Güeto, Susanna; Urós, Eva María; Ibáñez, Ester; Boronat, Albert; Rodríguez-Concepción, Manuel

    2006-02-06

    The 2-C-methyl-D-erythritol 4-phosphate pathway has been proposed as a promising target to develop new antimicrobial agents. However, spontaneous mutations in Escherichia coli were observed to rescue the otherwise lethal loss of the first two enzymes of the pathway, 1-deoxy-D-xylulose 5-phosphate (DXP) synthase (DXS) and DXP reductoisomerase (DXR), with a relatively high frequency. A mutation in the gene encoding the E1 subunit of the pyruvate dehydrogenase complex was shown to be sufficient to rescue the lack of DXS but not DXR in vivo, suggesting that the mutant enzyme likely allows the synthesis of DXP or an alternative substrate for DXR.

  15. Biosynthesis of isoprenoids: a bifunctional IspDF enzyme from Campylobacter jejuni.

    PubMed

    Gabrielsen, Mads; Rohdich, Felix; Eisenreich, Wolfgang; Gräwert, Tobias; Hecht, Stefan; Bacher, Adelbert; Hunter, William N

    2004-07-01

    In the nonmevalonate pathway of isoprenoid biosynthesis, the conversion of 2C-methyl-d-erythritol 4-phosphate into its cyclic diphosphate proceeds via nucleotidyl intermediates and is catalyzed by the products of the ispD, ispE and ispF genes. An open reading frame of Campylobacter jejuni with similarity to the ispD and ispF genes of Escherichia coli was cloned into an expression vector directing the formation of a 42 kDa protein in a recombinant E. coli strain. The purified protein was shown to catalyze the transformation of 2C-methyl-D-erythritol 4-phosphate into 4-diphosphocytidyl-2C-methyl-D-erythritol and the conversion of 4-diphosphocytidyl-2C-methyl-D-erythritol 2-phosphate into 2C-methyl-D-erythritol 2,4-cyclodiphosphate at catalytic rates of 19 micro mol x mg(-1) x min(-1) and 7 micro mol x mg(-1) x min(-1), respectively. Both enzyme-catalyzed reactions require divalent metal ions. The C. jejuni enzyme does not catalyze the formation of 2C-methyl-D-erythritol 3,4-cyclophosphate from 4-diphosphocytidyl-2C-methyl-D-erythritol, a side reaction catalyzed in vitro by the IspF proteins of E. coli and Plasmodium falciparum. Comparative genomic analysis show that all sequenced alpha- and epsilon-proteobacteria have fused ispDF genes. These bifunctional proteins are potential drug targets in several human pathogens (e.g. Helicobacter pylori, C. jejuni and Treponema pallidum).

  16. Hexameric assembly of the bifunctional methylerythritol 2,4-cyclodiphosphate synthase and protein-protein associations in the deoxy-xylulose-dependent pathway of isoprenoid precursor biosynthesis.

    PubMed

    Gabrielsen, Mads; Bond, Charles S; Hallyburton, Irene; Hecht, Stefan; Bacher, Adelbert; Eisenreich, Wolfgang; Rohdich, Felix; Hunter, William N

    2004-12-10

    The bifunctional methylerythritol 4-phosphate cytidylyltransferase methylerythritol 2,4-cyclodiphosphate synthase (IspDF) is unusual in that it catalyzes nonconsecutive reactions in the 1-deoxy-D-xylulose 5-phosphate (DOXP) pathway of isoprenoid precursor biosynthesis. The crystal structure of IspDF from the bacterial pathogen Campylobacter jejuni reveals an elongated hexamer with D3 symmetry compatible with the dimeric 2C-methyl-D-erythritol-4-phosphate cytidylyltransferase and trimeric 2C-methyl-D-erythritol-2,4-cyclodiphosphate synthase monofunctional enzymes. Complex formation of IspDF with 4-diphosphocytidyl-2C-methyl-D-erythritol kinase (IspE), the intervening enzyme activity in the pathway, has been observed in solution for the enzymes from C. jejuni and Agrobacterium tumefaciens. The monofunctional enzymes (2C-methyl-D-erythritol-4-phosphate cytidylyltransferase, IspE, and 2C-methyl-D-erythritol-2,4-cyclodiphosphate synthase) involved in the DOXP biosynthetic pathway of Escherichia coli also show physical associations. We propose that complex formation of the three enzymes at the core of the DOXP pathway can produce an assembly localizing 18 catalytic centers for the early stages of isoprenoid biosynthesis.

  17. The 2-C-methylerythritol 4-phosphate pathway in melon is regulated by specialized isoforms for the first and last steps

    PubMed Central

    Saladié, Montserrat; Wright, Louwrance P.; Garcia-Mas, Jordi; Rodriguez-Concepcion, Manuel; Phillips, Michael A.

    2014-01-01

    The 2-C-methyl-d-erythritol-4-phosphate (MEP) pathway provides the precursors for the biosynthesis of plastidial isoprenoids, which include the carotenoid pigments of many fruits. We have analysed the genes encoding the seven enzymes of the MEP pathway in melon (Cucumis melo L.) and determined that the first one, 1-deoxyxylulose 5-phosphate synthase (DXS), and the last one, 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate reductase (HDR), are represented in the genome as a small gene family and paralogous pair, respectively. In the case of DXS, three genes encode functional DXS activities which fall into previously established type I (CmDXS1) and II (CmDXS2a and CmDXS2b) categories, while a fourth DXS-like gene belonging to the type III group did not encode a protein with DXS activity. Their expression patterns and phylogenies suggest that CmDXS1 is functionally specialized for developmental and photosynthetic processes, while CmDXS2a and CmDXS2b are induced in flowers and ripening fruit of orange- (but not white-) fleshed varieties, coinciding with β-carotene accumulation. This is the first instance connecting type II DXS genes to specialized isoprenoid biosynthesis in the fruit of an agronomically important species. Two HDR paralogues were shown to encode functional enzymes, although only CmHDR1 was highly expressed in the tissues and developmental stages tested. Phylogenetic analysis showed that in cucurbits such as melon, these HDR paralogues probably arose through individual gene duplications in a common angiosperm ancestor, mimicking a prior division in gymnosperms, while other flowering plants, including apple, soy, canola, and poplar, acquired HDR duplicates recently as homoeologues through large-scale genome duplications. We report the influence of gene duplication history on the regulation of the MEP pathway in melon and the role of specialized MEP-pathway isoforms in providing precursors for β-carotene production in orange-fleshed melon varieties. PMID

  18. Absence of substrate channeling between active sites in the Agrobacterium tumefaciens IspDF and IspE enzymes of the methyl erythritol phosphate pathway.

    PubMed

    Lherbet, Christian; Pojer, Florence; Richard, Stéphane B; Noel, Joseph P; Poulter, C D

    2006-03-21

    The conversion of 2-C-methyl-d-erythritol 4-phosphate (MEP) to 2-C-methyl-d-erythritol 2,4-cyclodiphosphate (cMEDP) in the MEP entry into the isoprenoid biosynthetic pathway occurs in three consecutive steps catalyzed by the IspD, IspE, and IspF enzymes, respectively. In Agrobacterium tumefaciens the ispD and ispF genes are fused to encode a bifunctional enzyme that catalyzes the first (synthesis of 4-diphosphocytidyl-2-C-methyl d-erythritol) and third (synthesis of 2-C-methyl-d-erythritol 2,4-cyclodiphosphate) steps. Sedimentation velocity experiments indicate that the bifunctional IspDF enzyme and the IspE protein associate in solution, raising the possibility of substrate channeling among the active sites in these two proteins. Kinetic evidence for substrate channeling was sought by measuring the time courses for product formation during incubations of MEP, CTP, and ATP with the IspDF and IspE proteins with and without an excess of the inactive IspE(D152A) mutant in the presence or absence of 30% (v/v) glycerol. The time dependencies indicate that the enzyme-generated intermediates are not transferred from the IspD active site in IspDF to the active site of IspE or from the active site in IspE to the active site of the IspF module of IspDF.

  19. Organ- and Growing Stage-Specific Expression of Solanesol Biosynthesis Genes in Nicotiana tabacum Reveals Their Association with Solanesol Content.

    PubMed

    Yan, Ning; Zhang, Hongbo; Zhang, Zhongfeng; Shi, John; Timko, Michael P; Du, Yongmei; Liu, Xinmin; Liu, Yanhua

    2016-11-15

    Solanesol is a noncyclic terpene alcohol that is composed of nine isoprene units and mainly accumulates in solanaceous plants, especially tobacco (Nicotiana tabacum L.). In the present study, RNA-seq analyses of tobacco leaves, stems, and roots were used to identify putative solanesol biosynthesis genes. Six 1-deoxy-d-xylulose 5-phosphate synthase (DXS), two 1-deoxy-d-xylulose 5-phosphate reductoisomerase (DXR), two 2-C-methyl-d-erythritol 4-phosphate cytidylyltransferase (IspD), four 4-diphosphocytidyl-2-C-methyl-d-erythritol kinase (IspE), two 2-C-methyl-d-erythritol 2,4-cyclo-diphosphate synthase (IspF), four 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate synthase (IspG), two 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate reductase (IspH), six isopentenyl diphosphate isomerase (IPI), and two solanesyl diphosphate synthase (SPS) candidate genes were identified in the solanesol biosynthetic pathway. Furthermore, the two N. tabacum SPS proteins (NtSPS1 and NtSPS2), which possessed two conserved aspartate-rich DDxxD domains, were highly homologous with SPS enzymes from other solanaceous plant species. In addition, the solanesol contents of three organs and of leaves from four growing stages of tobacco plants corresponded with the distribution of chlorophyll. Our findings provide a comprehensive evaluation of the correlation between the expression of different biosynthesis genes and the accumulation of solanesol, thus providing valuable insight into the regulation of solanesol biosynthesis in tobacco.

  20. Function of AP2/ERF Transcription Factors Involved in the Regulation of Specialized Metabolism in Ophiorrhiza pumila Revealed by Transcriptomics and Metabolomics

    PubMed Central

    Udomsom, Nirin; Rai, Amit; Suzuki, Hideyuki; Okuyama, Jun; Imai, Ryosuke; Mori, Tetsuya; Nakabayashi, Ryo; Saito, Kazuki; Yamazaki, Mami

    2016-01-01

    The hairy roots (HR) of Ophiorrhiza pumila produce camptothecin (CPT), a monoterpenoid indole alkaloid used as a precursor in the synthesis of chemotherapeutic drugs. O. pumila HR culture is considered as a promising alternative source of CPT, however, the knowledge about the biosynthetic pathway and regulatory mechanism is still limited. In this study, five genes that encode AP2/ERF transcription factors, namely OpERF1–OpERF5, were isolated from HR of O. pumila. Phylogenetic analysis of AP2/ERF protein sequences suggested the close evolutionary relationship of OpERF1 with stress-responsive ERF factors in Arabidopsis and of OpERF2 with ERF factors reported to regulate alkaloid production, such as ORCA3 in Catharanthus roseus, NIC2 locus ERF in tobacco, and JRE4 in tomato. We generated the transgenic HR lines of O. pumila, ERF1i and ERF2i, in which the expression of OpERF1 and OpERF2, respectively, was suppressed using RNA interference technique. The transcriptome and metabolome of these suppressed HR were analyzed for functional characterization of OpERF1 and OpERF2. Although significant changes were not observed in the metabolome, including CPT and related compounds, the suppression of OpERF2 resulted in reduced expression of genes in the 2-C-methyl-d-erythritol 4-phosphate and secologanin-strictosidine pathways, which supply a precursor, strictosidine, for CPT biosynthesis. Furthermore, while it was not conclusive for OpERF1, enrichment analysis of differentially expressed genes in the suppressed HR showed that the gene ontology terms for oxidation-reduction, presumably involved in secondary metabolite pathways, were enriched in the ERF2i downregulated gene set. These results suggest a positive role of OpERF2 in regulating specialized metabolism in O. pumila. PMID:28018397

  1. Isoprenoid biosynthesis in higher plants and in Escherichia coli: on the branching in the methylerythritol phosphate pathway and the independent biosynthesis of isopentenyl diphosphate and dimethylallyl diphosphate.

    PubMed Central

    Hoeffler, Jean-François; Hemmerlin, Andréa; Grosdemange-Billiard, Catherine; Bach, Thomas J; Rohmer, Michel

    2002-01-01

    In the bacterium Escherichia coli, the mevalonic-acid (MVA)-independent 2-C-methyl-d-erythritol 4-phosphate (MEP) pathway is characterized by two branches leading separately to isopentenyl diphosphate (IPP) and dimethylallyl diphosphate (DMAPP). The signature of this branching is the retention of deuterium in DMAPP and the deuterium loss in IPP after incorporation of 1-[4-(2)H]deoxy-d-xylulose ([4-(2)H]DX). Feeding tobacco BY-2 cell-suspension cultures with [4-(2)H]DX resulted in deuterium retention in the isoprene units derived from DMAPP, as well as from IPP in the plastidial isoprenoids, phytoene and plastoquinone, synthesized via the MEP pathway. This labelling pattern represents direct evidence for the presence of the DMAPP branch of the MEP pathway in a higher plant, and shows that IPP can be synthesized from DMAPP in plant plastids, most probably via a plastidial IPP isomerase. PMID:12010124

  2. Differential incorporation of 1-deoxy-D-xylulose into (3S)-linalool and geraniol in grape berry exocarp and mesocarp.

    PubMed

    Luan, Fang; Wüst, Matthias

    2002-07-01

    In vivo feeding experiments with [5,5-(2)H(2)]mevalonic acid lactone (MVL) and [5,5-(2)H(2)]-1-deoxy-D-xylulose (DOX) indicate that the novel mevalonate-independent 1-deoxy- D-xylulose 5-phosphate/2C-methyl- D-erythritol 4-phosphate (DOXP/MEP) pathway is the dominant metabolic route for monoterpene biosynthesis in grape berry exocarp and mesocarp and in grape leaves. The highly uneven distribution of the monoterpene alcohols (3S)-linalool and geraniol between leaves, berry exocarp and berry mesocarp can be attributed to a compartmentation of monoterpene metabolism. In grape berries incorporation of [5,5-(2)H(2)]-DOX into geraniol is mainly restricted to the exocarp, whereas (3S)-linalool biosynthesis can be detected in exocarp as well as in mesocarp tissue. The results demonstrate that grape berries exhibit an autonomic monoterpene biosynthesis via the novel DOXP/MEP route throughout the ripening process.

  3. Validation of a homology model of Mycobacterium tuberculosis DXS: rationalization of observed activities of thiamine derivatives as potent inhibitors of two orthologues of DXS.

    PubMed

    Masini, T; Lacy, B; Monjas, L; Hawksley, D; de Voogd, A R; Illarionov, B; Iqbal, A; Leeper, F J; Fischer, M; Kontoyianni, M; Hirsch, A K H

    2015-12-14

    The enzyme DXS catalyzes the first, rate-limiting step of the 2-C-methyl-d-erythritol-4-phosphate (MEP, 1) pathway using thiamine diphosphate (ThDP) as cofactor; the DXS-catalyzed reaction constitutes also the first step in vitamin B1 and B6 metabolism in bacteria. DXS is the least studied among the enzymes of this pathway in terms of crystallographic information, with only one complete crystal structure deposited in the Protein Data Bank (Deinococcus radiodurans DXS, PDB: ). We synthesized a series of thiamine and ThDP derivatives and tested them for their biochemical activity against two DXS orthologues, namely D. radiodurans DXS and Mycobacterium tuberculosis DXS. These experimental results, combined with advanced docking studies, led to the development and validation of a homology model of M. tuberculosis DXS, which, in turn, will guide medicinal chemists in rationally designing potential inhibitors for M. tuberculosis DXS.

  4. Antisense and chemical suppression of the nonmevalonate pathway affects ent-kaurene biosynthesis in Arabidopsis.

    PubMed

    Okada, Kazunori; Kawaide, Hiroshi; Kuzuyama, Tomohisa; Seto, Haruo; Curtis, Ian S; Kamiya, Yuji

    2002-06-01

    Transgenic plants of Arabidopsis thaliana (L.) Heynh. (ecotype Columbia) expressing the antisense AtMECT gene, encoding 2- C-methyl- D-erythritol 4-phosphate cytidylyltransferase, were generated to elucidate the physiological role of the nonmevalonate pathway for production of ent-kaurene, the latter being the plastidic precursor of gibberellins. In transformed plants pigmentation and accumulation of ent-kaurene were reduced compared to wild-type plants. Fosmidomycin, an inhibitor of 1-deoxy- D-xylulose 5-phosphate reductoisomerase (DXR), caused a similar depletion of these compounds in transgenic plants. These observations suggest that both AtMECT and DXR are important in the synthesis of isopentenyl diphosphate and dimethylallyl diphosphate and that ent-kaurene is mainly produced through the nonmevalonate pathway in the plastid.

  5. Comparative glandular trichome transcriptome based gene characterization reveals reasons for differential (-)-menthol biosynthesis in Mentha species.

    PubMed

    Akhtar, Md Qussen; Qamar, Nida; Yadav, Pallavi; Kulkarni, Pallavi; Kumar, Ajay; Shasany, Ajit Kumar

    2017-02-11

    , isopulegone isomerase; IPR, isopiperitenone reductase; L3H, limonene 3-hydroxylase; LS, limonene synthase; MCS, 2-C-methyl-D-erythritol 2,4-cyclodiphosphate synthase; MCT, 2-C-methyl-D-erythritol 4-phosphate cytidylyltransferase; MD, menthol dehydrogenase; MEP, methylerythritol phosphate; MFS, menthofuran synthase; MVA, mevalonic acid; MVK, mevalonate kinase; NMD, neomenthol dehydrogenase, Nr, non-redundant; PMD, phosphomevalonate decarboxylase; PMK, phosphomevalonate kinase; PR, pulegone reductase; qRT-PCR, quantitative real-time polymerase chain reaction; SSR, simple sequence repeat; TPS, terpene synthase.

  6. Combination of vascular targeting PDT with combretastatin A4 phosphate

    NASA Astrophysics Data System (ADS)

    He, Chong; Fateye, Babasola; Chen, Bin

    2009-06-01

    Tumor vasculature is an attractive target for cancer therapy due to its accessibility to blood-borne therapeutic agents and the dependence of tumor cells on a functional blood supply for survival and growth. Vascular targeting photodynamic therapy (vPDT) is a novel modality based on the selective laser light activation of photosensitizers localized inside tumor vasculature to shutdown tumor vascular function. Although this vascular targeting therapy is showing great promise for cancer treatment, tumor recurrence has been observed in both preclinical and clinical studies. In this study, we intend to enhance the therapeutic outcome of vascular targeting PDT by combining it with combretastatin A4 phosphate (CA4P), a blood flow inhibitor. We found that the combination of CA4P and vPDT significantly increased endothelial cell apoptosis than each single therapy. Western blot analysis suggests that myosin light chain kinase (MLCK) is a common target of CA4P and vPDT. In a PC-3 prostate tumor model, we found that CA4P was able to greatly enhance tumor response to vPDT. These results demonstrate that CA4P and vPDT can be combined to enhance the therapeutic effect.

  7. Characterization of 1-hydroxy-2-methyl-2-(E)-butenyl-4-diphosphate synthase (HDS) gene from Ginkgo biloba.

    PubMed

    Kim, Sang-Min; Kim, Soo-Un

    2010-02-01

    Diterpene trilactone ginkgolides, one of the major constituents of Ginkgo biloba extract, have shown interesting bioactivities including platelet-activating factor antagonistic activity. 1-Hydroxy-2-methyl-2-(E)-butenyl-4-diphosphate synthase (HDS), converting 2-C-methyl-d-erythritol-2,4-cyclodiphosphate into 1-hydroxy-2-methyl-2-(E)-butenyl-4-diphosphate, is the penultimate enzyme of the seven-step 2-C-methyl-d-erythritol 4-phosphate pathway that supplies building blocks for plant isoprenoids of plastid origin such as ginkgolides and carotenoids. Here, we report on the isolation and characterization of the full-length cDNA encoding HDS (GbHDS, GenBank accession number: DQ251630) from G. biloba. Full-length cDNA of GbHDS, 2,763 bp long, contained an ORF of 2,226 bp encoding a protein composed of 741 amino acids. The theoretical molecular weight and pI of the deduced mature GbHDS of 679 amino acid residues are 75.6 kDa and 5.5, respectively. From 2 weeks after initiation of the culture onward, transcription level of this gene in the ginkgo embryo roots increased to about two times higher than that in the leaves. GbHDS was predicted to possess chloroplast transit peptide of 62 amino acid residues, suggesting its putative localization in the plastids. The transient gene expression in Arabidopsis protoplasts confirmed that the transit peptide was capable of delivering the GbHDS protein from the cytosol into the chloroplasts. The isolation and characterization of GbHDS gene enabled us to further understand the role of GbHDS in the terpenoid biosynthesis in G. biloba.

  8. Multiphasic dynamics of phosphatidylinositol 4-phosphate during phagocytosis

    PubMed Central

    Levin, Roni; Hammond, Gerald R. V.; Balla, Tamas; De Camilli, Pietro; Fairn, Gregory D.; Grinstein, Sergio

    2017-01-01

    We analyzed the distribution, fate, and functional role of phosphatidylinositol 4-phosphate (PtdIns4P) during phagosome formation and maturation. To this end, we used genetically encoded probes consisting of the PtdIns4P-binding domain of the bacterial effector SidM. PtdIns4P was found to undergo complex, multiphasic changes during phagocytosis. The phosphoinositide, which is present in the plasmalemma before engagement of the target particle, is transiently enriched in the phagosomal cup. Soon after the phagosome seals, PtdIns4P levels drop precipitously due to the hydrolytic activity of Sac2 and phospholipase C, becoming undetectable for ∼10 min. PtdIns4P disappearance coincides with the emergence of phagosomal PtdIns3P. Conversely, the disappearance of PtdIns3P that signals the transition from early to late phagosomes is accompanied by resurgence of PtdIns4P, which is associated with the recruitment of phosphatidylinositol 4-kinase 2A. The reacquisition of PtdIns4P can be prevented by silencing expression of the kinase and can be counteracted by recruitment of a 4-phosphatase with a heterodimerization system. Using these approaches, we found that the secondary accumulation of PtdIns4P is required for proper phagosomal acidification. Defective acidification may be caused by impaired recruitment of Rab7 effectors, including RILP, which were shown earlier to displace phagosomes toward perinuclear lysosomes. Our results show multimodal dynamics of PtdIns4P during phagocytosis and suggest that the phosphoinositide plays important roles during the maturation of the phagosome. PMID:28035045

  9. Natural variation in monoterpene synthesis in kiwifruit: transcriptional regulation of terpene synthases by NAC and ETHYLENE-INSENSITIVE3-like transcription factors.

    PubMed

    Nieuwenhuizen, Niels J; Chen, Xiuyin; Wang, Mindy Y; Matich, Adam J; Perez, Ramon Lopez; Allan, Andrew C; Green, Sol A; Atkinson, Ross G

    2015-04-01

    Two kiwifruit (Actinidia) species with contrasting terpene profiles were compared to understand the regulation of fruit monoterpene production. High rates of terpinolene production in ripe Actinidia arguta fruit were correlated with increasing gene and protein expression of A. arguta terpene synthase1 (AaTPS1) and correlated with an increase in transcript levels of the 2-C-methyl-D-erythritol 4-phosphate pathway enzyme 1-deoxy-D-xylulose-5-phosphate synthase (DXS). Actinidia chinensis terpene synthase1 (AcTPS1) was identified as part of an array of eight tandemly duplicated genes, and AcTPS1 expression and terpene production were observed only at low levels in developing fruit. Transient overexpression of DXS in Nicotiana benthamiana leaves elevated monoterpene synthesis by AaTPS1 more than 100-fold, indicating that DXS is likely to be the key step in regulating 2-C-methyl-D-erythritol 4-phosphate substrate flux in kiwifruit. Comparative promoter analysis identified potential NAC (for no apical meristem [NAM], Arabidopsis transcription activation factor [ATAF], and cup-shaped cotyledon [CUC])-domain transcription factor) and ETHYLENE-INSENSITIVE3-like transcription factor (TF) binding sites in the AaTPS1 promoter, and cloned members of both TF classes were able to activate the AaTPS1 promoter in transient assays. Electrophoretic mobility shift assays showed that AaNAC2, AaNAC3, and AaNAC4 bind a 28-bp fragment of the proximal NAC binding site in the AaTPS1 promoter but not the A. chinensis AcTPS1 promoter, where the NAC binding site was mutated. Activation could be restored by reintroducing multiple repeats of the 12-bp NAC core-binding motif. The absence of NAC transcriptional activation in ripe A. chinensis fruit can account for the low accumulation of AcTPS1 transcript, protein, and monoterpene volatiles in this species. These results indicate the importance of NAC TFs in controlling monoterpene production and other traits in ripening fruits.

  10. Natural Variation in Monoterpene Synthesis in Kiwifruit: Transcriptional Regulation of Terpene Synthases by NAC and ETHYLENE-INSENSITIVE3-Like Transcription Factors1

    PubMed Central

    Nieuwenhuizen, Niels J.; Chen, Xiuyin; Wang, Mindy Y.; Matich, Adam J.; Perez, Ramon Lopez; Allan, Andrew C.; Green, Sol A.; Atkinson, Ross G.

    2015-01-01

    Two kiwifruit (Actinidia) species with contrasting terpene profiles were compared to understand the regulation of fruit monoterpene production. High rates of terpinolene production in ripe Actinidia arguta fruit were correlated with increasing gene and protein expression of A. arguta terpene synthase1 (AaTPS1) and correlated with an increase in transcript levels of the 2-C-methyl-d-erythritol 4-phosphate pathway enzyme 1-deoxy-d-xylulose-5-phosphate synthase (DXS). Actinidia chinensis terpene synthase1 (AcTPS1) was identified as part of an array of eight tandemly duplicated genes, and AcTPS1 expression and terpene production were observed only at low levels in developing fruit. Transient overexpression of DXS in Nicotiana benthamiana leaves elevated monoterpene synthesis by AaTPS1 more than 100-fold, indicating that DXS is likely to be the key step in regulating 2-C-methyl-d-erythritol 4-phosphate substrate flux in kiwifruit. Comparative promoter analysis identified potential NAC (for no apical meristem [NAM], Arabidopsis transcription activation factor [ATAF], and cup-shaped cotyledon [CUC])-domain transcription factor) and ETHYLENE-INSENSITIVE3-like transcription factor (TF) binding sites in the AaTPS1 promoter, and cloned members of both TF classes were able to activate the AaTPS1 promoter in transient assays. Electrophoretic mobility shift assays showed that AaNAC2, AaNAC3, and AaNAC4 bind a 28-bp fragment of the proximal NAC binding site in the AaTPS1 promoter but not the A. chinensis AcTPS1 promoter, where the NAC binding site was mutated. Activation could be restored by reintroducing multiple repeats of the 12-bp NAC core-binding motif. The absence of NAC transcriptional activation in ripe A. chinensis fruit can account for the low accumulation of AcTPS1 transcript, protein, and monoterpene volatiles in this species. These results indicate the importance of NAC TFs in controlling monoterpene production and other traits in ripening fruits. PMID:25649633

  11. Phosphatidylinositol(4,5)bisphosphate and phosphatidylinositol(4)phosphate in plant tissues. [Pisum sativum

    SciTech Connect

    Irvine, R.F.; Letcher, A.J.; Lander, D.J. ); Dawson, A.P. ); Musgrave, A. ); Drobak, B.K. )

    1989-03-01

    Pea (Pisum sativum) leaf discs or swimming suspensions of Chlamydomonas eugametos were radiolabeled with ({sup 3}H)myo-inositol or ({sup 32}P)Pi and the lipids were extracted, deacylated, and their glycerol moieties removed. The resulting inositol trisphosphate and bisphosphate fractions were examined by periodate degradation, reduction and dephosphorylation, or by incubation with human red cell membranes. Their likely structures were identified as D-myo-inositol(1,4,5)trisphosphate and D-myo-inositol(1,4,)-bisphosphate. It is concluded that plants contain phosphatidylinositol(4)phosphate and phosphatidylinositol(4,5)bisphosphate; no other polyphosphoinositides were detected.

  12. Type I phosphatidylinositol 4-phosphate 5-kinase homo- and heterodimerization determines its membrane localization and activity.

    PubMed

    Lacalle, Rosa Ana; de Karam, Juan C; Martínez-Muñoz, Laura; Artetxe, Ibai; Peregil, Rosa M; Sot, Jesús; Rojas, Ana M; Goñi, Félix M; Mellado, Mario; Mañes, Santos

    2015-06-01

    Type I phosphatidylinositol 4-phosphate 5-kinases (PIP5KIs; α, β, and γ) are a family of isoenzymes that produce phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2] using phosphatidylinositol 4-phosphate as substrate. Their structural homology with the class II lipid kinases [type II phosphatidylinositol 5-phosphate 4-kinase (PIP4KII)] suggests that PIP5KI dimerizes, although this has not been formally demonstrated. Neither the hypothetical structural dimerization determinants nor the functional consequences of dimerization have been studied. Here, we used Förster resonance energy transfer, coprecipitation, and ELISA to show that PIP5KIβ forms homo- and heterodimers with PIP5KIγ_i2 in vitro and in live human cells. Dimerization appears to be a general phenomenon for PIP5KI isoenzymes because PIP5KIβ/PIP5KIα heterodimers were also detected by mass spectrometry. Dimerization was independent of actin cytoskeleton remodeling and was also observed using purified proteins. Mutagenesis studies of PIP5KIβ located the dimerization motif at the N terminus, in a region homologous to that implicated in PIP4KII dimerization. PIP5KIβ mutants whose dimerization was impaired showed a severe decrease in PI(4,5)P2 production and plasma membrane delocalization, although their association to lipid monolayers was unaltered. Our results identify dimerization as an integral feature of PIP5K proteins and a central determinant of their enzyme activity.

  13. Erythritol feeds the pentose phosphate pathway via three new isomerases leading to D-erythrose-4-phosphate in Brucella

    PubMed Central

    Barbier, Thibault; Collard, François; Zúñiga-Ripa, Amaia; Moriyón, Ignacio; Godard, Thibault; Becker, Judith; Wittmann, Christoph; Van Schaftingen, Emile; Letesson, Jean-Jacques

    2014-01-01

    Erythritol is an important nutrient for several α-2 Proteobacteria, including N2-fixing plant endosymbionts and Brucella, a worldwide pathogen that finds this four-carbon polyol in genital tissues. Erythritol metabolism involves phosphorylation to l-erythritol-4-phosphate by the kinase EryA and oxidation of the latter to l-3-tetrulose 4-phosphate by the dehydrogenase EryB. It is accepted that further steps involve oxidation by the putative dehydrogenase EryC and subsequent decarboxylation to yield triose-phosphates. Accordingly, growth on erythritol as the sole C source should require aldolase and fructose-1,6-bisphosphatase to produce essential hexose-6-monophosphate. However, we observed that a mutant devoid of fructose-1,6-bisphosphatases grew normally on erythritol and that EryC, which was assumed to be a dehydrogenase, actually belongs to the xylose isomerase superfamily. Moreover, we found that TpiA2 and RpiB, distant homologs of triose phosphate isomerase and ribose 5-phosphate isomerase B, were necessary, as previously shown for Rhizobium. By using purified recombinant enzymes, we demonstrated that l-3-tetrulose-4-phosphate was converted to d-erythrose 4-phosphate through three previously unknown isomerization reactions catalyzed by EryC (tetrulose-4-phosphate racemase), TpiA2 (d-3-tetrulose-4-phosphate isomerase; renamed EryH), and RpiB (d-erythrose-4-phosphate isomerase; renamed EryI), a pathway fully consistent with the isotopomer distribution of the erythrose-4-phosphate-derived amino acids phenylalanine and tyrosine obtained from bacteria grown on 13C-labeled erythritol. d-Erythrose-4-phosphate is then converted by enzymes of the pentose phosphate pathway to glyceraldehyde 3-phosphate and fructose 6-phosphate, thus bypassing fructose-1,6-bisphosphatase. This is the first description to our knowledge of a route feeding carbohydrate metabolism exclusively via d-erythrose 4-phosphate, a pathway that may provide clues to the preferential metabolism of

  14. Erythritol feeds the pentose phosphate pathway via three new isomerases leading to D-erythrose-4-phosphate in Brucella.

    PubMed

    Barbier, Thibault; Collard, François; Zúñiga-Ripa, Amaia; Moriyón, Ignacio; Godard, Thibault; Becker, Judith; Wittmann, Christoph; Van Schaftingen, Emile; Letesson, Jean-Jacques

    2014-12-16

    Erythritol is an important nutrient for several α-2 Proteobacteria, including N2-fixing plant endosymbionts and Brucella, a worldwide pathogen that finds this four-carbon polyol in genital tissues. Erythritol metabolism involves phosphorylation to L-erythritol-4-phosphate by the kinase EryA and oxidation of the latter to L-3-tetrulose 4-phosphate by the dehydrogenase EryB. It is accepted that further steps involve oxidation by the putative dehydrogenase EryC and subsequent decarboxylation to yield triose-phosphates. Accordingly, growth on erythritol as the sole C source should require aldolase and fructose-1,6-bisphosphatase to produce essential hexose-6-monophosphate. However, we observed that a mutant devoid of fructose-1,6-bisphosphatases grew normally on erythritol and that EryC, which was assumed to be a dehydrogenase, actually belongs to the xylose isomerase superfamily. Moreover, we found that TpiA2 and RpiB, distant homologs of triose phosphate isomerase and ribose 5-phosphate isomerase B, were necessary, as previously shown for Rhizobium. By using purified recombinant enzymes, we demonstrated that L-3-tetrulose-4-phosphate was converted to D-erythrose 4-phosphate through three previously unknown isomerization reactions catalyzed by EryC (tetrulose-4-phosphate racemase), TpiA2 (D-3-tetrulose-4-phosphate isomerase; renamed EryH), and RpiB (D-erythrose-4-phosphate isomerase; renamed EryI), a pathway fully consistent with the isotopomer distribution of the erythrose-4-phosphate-derived amino acids phenylalanine and tyrosine obtained from bacteria grown on (13)C-labeled erythritol. D-erythrose-4-phosphate is then converted by enzymes of the pentose phosphate pathway to glyceraldehyde 3-phosphate and fructose 6-phosphate, thus bypassing fructose-1,6-bisphosphatase. This is the first description to our knowledge of a route feeding carbohydrate metabolism exclusively via D-erythrose 4-phosphate, a pathway that may provide clues to the preferential metabolism of

  15. Effects of polyamines and calcium and sodium ions on smooth muscle cytoskeleton-associated phosphatidylinositol (4)-phosphate 5-kinase.

    PubMed

    Chen, H; Baron, C B; Griffiths, T; Greeley, P; Coburn, R F

    1998-10-01

    In many different cell types, including smooth muscle cells (Baron et al., 1989, Am. J. Physiol., 256: C375-383; Baron et al., J. Pharmacol. Exp. Ther. 266: 8-15), phosphatidylinositol (4)-phosphate 5-kinase plays a critical role in the regulation of membrane concentrations of phosphatidylinositol (4,5)-bisphosphate and formation of inositol (1,4,5)-trisphosphate. In unstimulated porcine trachealis smooth muscle, 70% of total cellular phosphatidylinositol (4)-phosphate 5-kinase activity was associated with cytoskeletal proteins and only trace activity was detectable in isolated sarcolemma. Using two different preparations, we studied cytoskeleton-associated phosphatidyl inositol (4)-phosphate 5-kinase under conditions that attempted to mimic the ionic and thermal cytoplasmic environment of living cells. The cytoskeleton-associated enzyme, studied using phosphatidylinositol (4)-phosphate substrate concentrations that produced phosphatidylinositol 4,5-bisphosphate at about 10% of the maximal rate, was sensitive to free [Mg2+], had an absolute requirement for phosphatidylserine, phosphatidic acid, or phosphatidylinositol, and included type I isoforms. At 0.5 mM free [Mg2+], physiological spermine concentrations, 0.2-0.4 mM, increased phosphatidylinositol (4)-phosphate 5-kinase activity two to four times compared to controls run without spermine. The EC50 for spermine-evoked increases in activity was 0.17 +/- 0.02 mM. Spermine-evoked enzyme activity was a function of both free [Mg2+] and substrate concentration. Cytoskeleton-associated phosphatidylinositol (4)-phosphate 5-kinase was inhibited by free [Ca2+] over a physiological range for cytoplasm--10(-8) to 10(-5) M, an effect independent of the presence of calmodulin. Na+ over the range 20 to 50 mM also inhibited this enzyme activated by 5 mM Mg2+ but had no effect on spermine-activated enzyme. Na+, Ca2+, and spermine appear to be physiological modulators of smooth muscle cytoskeleton-bound phosphatidylinositol (4

  16. Histones Cause Aggregation and Fusion of Lipid Vesicles Containing Phosphatidylinositol-4-Phosphate

    PubMed Central

    Lete, Marta G.; Sot, Jesus; Gil, David; Valle, Mikel; Medina, Milagros; Goñi, Felix M.; Alonso, Alicia

    2015-01-01

    In a previous article, we demonstrated that histones (H1 or histone octamers) interact with negatively charged bilayers and induce extensive aggregation of vesicles containing phosphatidylinositol-4-phosphate (PIP) and, to a lesser extent, vesicles containing phosphatidylinositol (PI). Here, we found that vesicles containing PIP, but not those containing PI, can undergo fusion induced by histones. Fusion was demonstrated through the observation of intervesicular mixing of total lipids and inner monolayer lipids, and by ultrastructural and confocal microscopy studies. Moreover, in both PI- and PIP-containing vesicles, histones caused permeabilization and release of vesicular aqueous contents, but the leakage mechanism was different (all-or-none for PI and graded release for PIP vesicles). These results indicate that histones could play a role in the remodeling of the nuclear envelope that takes place during the mitotic cycle. PMID:25692591

  17. Histones cause aggregation and fusion of lipid vesicles containing phosphatidylinositol-4-phosphate.

    PubMed

    Lete, Marta G; Sot, Jesus; Gil, David; Valle, Mikel; Medina, Milagros; Goñi, Felix M; Alonso, Alicia

    2015-02-17

    In a previous article, we demonstrated that histones (H1 or histone octamers) interact with negatively charged bilayers and induce extensive aggregation of vesicles containing phosphatidylinositol-4-phosphate (PIP) and, to a lesser extent, vesicles containing phosphatidylinositol (PI). Here, we found that vesicles containing PIP, but not those containing PI, can undergo fusion induced by histones. Fusion was demonstrated through the observation of intervesicular mixing of total lipids and inner monolayer lipids, and by ultrastructural and confocal microscopy studies. Moreover, in both PI- and PIP-containing vesicles, histones caused permeabilization and release of vesicular aqueous contents, but the leakage mechanism was different (all-or-none for PI and graded release for PIP vesicles). These results indicate that histones could play a role in the remodeling of the nuclear envelope that takes place during the mitotic cycle.

  18. Combretastatin A4-phosphate and its potential in veterinary oncology: a review.

    PubMed

    Abma, E; Daminet, S; Smets, P; Ni, Y; de Rooster, H

    2017-03-01

    For many years, research on anticancer therapy has focussed almost exclusively on targeting cancer cells directly, to selectively kill them or restrict their growth. But limited advances in this strategy have led researchers to shift their attention to other potential targets. Active research is now on-going on targeting tumour stroma. Vascular disrupting agents (VDAs) appear a promising class of anticancer drugs that are currently under investigation as a sole or combined therapy in human cancer patients. This article will briefly touch on the history and biology of combretastatin A4-phosphate (CA4P) as a typical example of VDAs and will concentrate on the side effects that can be expected when used in veterinary patients. Particularly, the pathogenesis of these side effects and how they may be prevented and/or treated will be discussed. The purpose of this article is to illustrate the potentials of CA4P as anticancer therapy in veterinary oncology patients.

  19. Improving peppermint essential oil yield and composition by metabolic engineering.

    PubMed

    Lange, Bernd Markus; Mahmoud, Soheil Seyed; Wildung, Mark R; Turner, Glenn W; Davis, Edward M; Lange, Iris; Baker, Raymond C; Boydston, Rick A; Croteau, Rodney B

    2011-10-11

    Peppermint (Mentha × piperita L.) was transformed with various gene constructs to evaluate the utility of metabolic engineering for improving essential oil yield and composition. Oil yield increases were achieved by overexpressing genes involved in the supply of precursors through the 2C-methyl-D-erythritol 4-phosphate (MEP) pathway. Two-gene combinations to enhance both oil yield and composition in a single transgenic line were assessed as well. The most promising results were obtained by transforming plants expressing an antisense version of (+)-menthofuran synthase, which is critical for adjusting the levels of specific undesirable oil constituents, with a construct for the overexpression of the MEP pathway gene 1-deoxy-D-xylulose 5-phosphate reductoisomerase (up to 61% oil yield increase over wild-type controls with low levels of the undesirable side-product (+)-menthofuran and its intermediate (+)-pulegone). Elite transgenic lines were advanced to multiyear field trials, which demonstrated consistent oil yield increases of up to 78% over wild-type controls and desirable effects on oil composition under commercial growth conditions. The transgenic expression of a gene encoding (+)-limonene synthase was used to accumulate elevated levels of (+)-limonene, which allows oil derived from transgenic plants to be recognized during the processing of commercial formulations containing peppermint oil. Our study illustrates the utility of metabolic engineering for the sustainable agricultural production of high quality essential oils at a competitive cost.

  20. Cloning and Expression Analysis of MEP Pathway Enzyme-encoding Genes in Osmanthus fragrans

    PubMed Central

    Xu, Chen; Li, Huogeng; Yang, Xiulian; Gu, Chunsun; Mu, Hongna; Yue, Yuanzheng; Wang, Lianggui

    2016-01-01

    The 2-C-methyl-d-erythritol 4-phosphate (MEP) pathway is responsible for the biosynthesis of many crucial secondary metabolites, such as carotenoids, monoterpenes, plastoquinone, and tocopherols. In this study, we isolated and identified 10 MEP pathway genes in the important aromatic plant sweet osmanthus (Osmanthus fragrans). Multiple sequence alignments revealed that 10 MEP pathway genes shared high identities with other reported proteins. The genes showed distinctive expression profiles in various tissues, or at different flower stages and diel time points. The qRT-PCR results demonstrated that these genes were highly expressed in inflorescences, which suggested a tissue-specific transcript pattern. Our results also showed that OfDXS1, OfDXS2, and OfHDR1 had a clear diurnal oscillation pattern. The isolation and expression analysis provides a strong foundation for further research on the MEP pathway involved in gene function and molecular evolution, and improves our understanding of the molecular mechanism underlying this pathway in plants. PMID:27690108

  1. Enhanced Diterpene Tanshinone Accumulation and Bioactivity of Transgenic Salvia miltiorrhiza Hairy Roots by Pathway Engineering.

    PubMed

    Shi, Min; Luo, Xiuqin; Ju, Guanhua; Li, Leilei; Huang, Shengxiong; Zhang, Tong; Wang, Huizhong; Kai, Guoyin

    2016-03-30

    Tanshinones are health-promoting diterpenoids found in Salvia miltiorrhiza and have wide applications. Here, SmGGPPS (geranylgeranyl diphosphate synthase) and SmDXSII (1-deoxy-D-xylulose-5-phosphate synthase) were introduced into hairy roots of S. miltiorrhiza. Overexpression of SmGGPPS and SmDXSII in hairy roots produces higher levels of tanshinone than control and single-gene transformed lines; tanshinone production in the double-gene transformed line GDII10 reached 12.93 mg/g dry weight, which is the highest tanshinone content that has been achieved through genetic engineering. Furthermore, transgenic hairy root lines showed higher antioxidant and antitumor activities than control lines. In addition, contents of chlorophylls, carotenoids, indoleacetic acid, and gibberellins were significantly elevated in transgenic Arabidopsis thaliana plants. These results demonstrate a promising method to improve the production of diterpenoids including tanshinone as well as other natural plastid-derived isoprenoids in plants by genetic manipulation of the 2-C-methyl-D-erythritol-4-phosphate (MEP) pathway.

  2. Molecular cloning, functional characterization and expression of potato (Solanum tuberosum) 1-deoxy-d-xylulose 5-phosphate synthase 1 (StDXS1) in response to Phytophthora infestans.

    PubMed

    Henriquez, Maria Antonia; Soliman, Atta; Li, Genyi; Hannoufa, Abdelali; Ayele, Belay T; Daayf, Fouad

    2016-02-01

    1-Deoxy-D-xylulose 5-phosphate synthase (DXS) catalyzes the initial step of the plastidial 2C-methyl-D-erythritol-4-phosphate (DOXP-MEP) pathway involved in isoprenoid biosynthesis. In this study, we cloned the complete cDNA of potato DXS gene that was designated StDXS1. StDXS1 cDNA encodes for 719 amino acid residues, with MW of 77.8 kDa, and is present in one copy in the potato genome. Phylogenetic analysis and protein sequence alignments assigned StDXS1 to a group with DXS homologues from closely related species and exhibited homodomain identity with known DXS proteins from other plant species. Late blight symptoms occurred in parallel with a reduction in StDXS1 transcript levels, which may be associated with the levels of isoprenoids that contribute to plant protection against pathogens. Subcellular localization indicated that StDXS1 targets the chloroplasts where isoprenoids are synthesized. Arabidopsis expressing StDXS1 showed a higher accumulation of carotenoids and chlorophyll as compared to wild type controls. Lower levels of ABA and GA were detected in the transgenic DXS lines as compared to control plants, which reflected on higher germination rates of the transgenic DXS lines. No changes were detected in JA or SA contents. Selected downstream genes in the DOXP-MEP pathway, especially GGPPS genes, were up-regulated in the transgenic lines.

  3. Effects of fosmidomycin on plant photosynthesis as measured by gas exchange and chlorophyll fluorescence.

    PubMed

    Possell, Malcolm; Ryan, Annette; Vickers, Claudia E; Mullineaux, Philip M; Hewitt, C Nicholas

    2010-04-01

    In higher plants, many isoprenoids are synthesised via the chloroplastic 1-deoxy-D-xylulose 5-phosphate/2-C-methyl-D-erythritol 4-phosphate (MEP) pathway. Attempts to elucidate the function of individual isoprenoids have used the antibiotic/herbicidal compound fosmidomycin (3-[N-formyl-N-hydroxy amino] propyl phosphonic acid) to inhibit this pathway. Examination of the effect of fosmidomycin on the major components of photosynthesis in leaves of white poplar (Populus alba) and tobacco (Nicotiana tabacum) was made. Fosmidomycin reduced net photosynthesis in both species within 1 h of application, but only when photosynthesis was light-saturated. In P. alba, these reductions were confounded by high light and fosmidomycin inducing stomatal patchiness. In tobacco, this was caused by significant reductions in PSII chlorophyll fluorescence and reductions in V(cmax) and J(max). Our data indicate that the diminution of photosynthesis is likely a complex effect resulting from the inhibition of multiple MEP pathway products, resulting in photoinhibition and photo-damage. These effects should be accounted for in experimental design and analysis when using fosmidomycin to avoid misinterpretation of results as measured by gas exchange and chlorophyll fluorescence.

  4. A functional (E)-4-hydroxy-3-methylbut-2-enyl diphosphate reductase exhibits diurnal regulation of expression in Stevia rebaudiana (Bertoni).

    PubMed

    Kumar, Hitesh; Kumar, Sanjay

    2013-09-15

    The leaves of stevia [Stevia rebaudiana (Bertoni)] are a rich source of steviol glycosides that are used as non-calorific sweetener in many countries around the world. Steviol moiety of steviol glycosides is synthesized via plastidial 2C-methyl-D-erythritol 4-phosphate pathway, where (E)-4-hydroxy-3-methylbut-2-enyl diphosphate reductase (HDR) is the key enzyme. HDR catalyzes the simultaneous conversion of (E)-4-hydroxy-3-methylbut-2-enyl diphosphate into five carbon isoprenoid units, isopentenyl diphosphate and dimethylallyl diphosphate. Stevia HDR (SrHDR) successfully rescued HDR lethal mutant strain MG1655 ara<>ispH upon genetic complementation, suggesting SrHDR to encode a functional protein. The gene exhibited diurnal variation in expression. To identify the possible regulatory elements, upstream region of the gene was cloned and putative cis-acting elements were detected by in silico analysis. Electrophoretic mobility shift assay, using a putative light responsive element GATA showed the binding of nuclear proteins (NP) isolated from leaves during light period of the day, but not with the NP from leaves during the dark period. Data suggested the involvement of GATA box in light mediated gene regulation of SrHDR in stevia.

  5. Overexpression and Suppression of Artemisia annua 4-Hydroxy-3-Methylbut-2-enyl Diphosphate Reductase 1 Gene (AaHDR1) Differentially Regulate Artemisinin and Terpenoid Biosynthesis

    PubMed Central

    Ma, Dongming; Li, Gui; Zhu, Yue; Xie, De-Yu

    2017-01-01

    4-Hydroxy-3-methylbut-2-enyl diphosphate reductase (HDR) catalyzes the last step of the 2-C-methyl-D-erythritol 4- phosphate (MEP) pathway to synthesize isopentenyl pyrophosphate (IPP) and dimethylallyl diphosphate (DMAPP). To date, little is known regarding effects of an increase or a decrease of a HDR expression on terpenoid and other metabolite profiles in plants. In our study, an Artemisia annua HDR cDNA (namely AaHDR1) was cloned from leaves. Expression profiling showed that it was highly expressed in leaves, roots, stems, and flowers with different levels. Green florescence protein fusion and confocal microscope analyses showed that AaHDR1 was localized in chloroplasts. The overexpression of AaHDR1 increased contents of artemisinin, arteannuin B and other sesquiterpenes, and multiple monoterpenes. By contrast, the suppression of AaHDR1 by anti-sense led to opposite results. In addition, an untargeted metabolic profiling showed that the overexpression and suppression altered non-polar metabolite profiles. In conclusion, the overexpression and suppression of AaHDR1 protein level in plastids differentially affect artemisinin and other terpenoid biosynthesis, and alter non-polar metabolite profiles of A. annua. Particularly, its overexpression leading to the increase of artemisinin production is informative to future metabolic engineering of this antimalarial medicine. PMID:28197158

  6. A Geranylfarnesyl Diphosphate Synthase Provides the Precursor for Sesterterpenoid (C25) Formation in the Glandular Trichomes of the Mint Species Leucosceptrum canum

    PubMed Central

    Luo, Shi-Hong; Schmidt, Axel; Sun, Gui-Ling; Kuang, Ce; Yang, Min-Jie; Jing, Shu-Xi; Li, Chun-Huan

    2016-01-01

    Plant sesterterpenoids, an important class of terpenoids, are widely distributed in various plants, including food crops. However, little is known about their biosynthesis. Here, we cloned and functionally characterized a plant geranylfarnesyl diphosphate synthase (Lc-GFDPS), the enzyme producing the C25 prenyl diphosphate precursor to all sesterterpenoids, from the glandular trichomes of the woody plant Leucosceptrum canum. GFDPS catalyzed the formation of GFDP after expression in Escherichia coli. Overexpressing GFDPS in Arabidopsis thaliana also gave an extract catalyzing GFDP formation. GFDPS was strongly expressed in glandular trichomes, and its transcript profile was completely in accordance with the sesterterpenoid accumulation pattern. GFDPS is localized to the plastids, and inhibitor studies indicated its use of isoprenyl diphosphate substrates supplied by the 2-C-methyl-d-erythritol 4-phosphate pathway. Application of a jasmonate defense hormone induced GFDPS transcript and sesterterpenoid accumulation, while reducing feeding and growth of the generalist insect Spodoptera exigua, suggesting that these C25 terpenoids play a defensive role. Phylogenetic analysis suggested that GFDPS probably evolved from plant geranylgeranyl diphosphate synthase under the influence of positive selection. The isolation of GFDPS provides a model for investigating sesterterpenoid formation in other species and a tool for manipulating the formation of this group in plants and other organisms. PMID:26941091

  7. Overexpressing 3-Hydroxy-3-Methylglutaryl Coenzyme A Reductase (HMGR) in the Lactococcal Mevalonate Pathway for Heterologous Plant Sesquiterpene Production

    PubMed Central

    Song, Adelene Ai-Lian; Abdullah, Janna Ong; Abdullah, Mohd. Puad; Shafee, Norazizah; Othman, Roohaida; Tan, Ee-Fun; Noor, Normah Mohd.; Raha, Abdul Rahim

    2012-01-01

    Isoprenoids are a large and diverse group of metabolites with interesting properties such as flavour, fragrance and therapeutic properties. They are produced via two pathways, the mevalonate pathway or the 2-C-methyl-D-erythritol-4-phosphate (MEP) pathway. While plants are the richest source of isoprenoids, they are not the most efficient producers. Escherichia coli and yeasts have been extensively studied as heterologous hosts for plant isoprenoids production. In the current study, we describe the usage of the food grade Lactococcus lactis as a potential heterologous host for the production of sesquiterpenes from a local herbaceous Malaysian plant, Persicaria minor (synonym Polygonum minus). A sesquiterpene synthase gene from P. minor was successfully cloned and expressed in L. lactis. The expressed protein was identified to be a β-sesquiphellandrene synthase as it was demonstrated to be functional in producing β-sesquiphellandrene at 85.4% of the total sesquiterpenes produced based on in vitro enzymatic assays. The recombinant L. lactis strain developed in this study was also capable of producing β-sesquiphellandrene in vivo without exogenous substrates supplementation. In addition, overexpression of the strain’s endogenous 3-hydroxy-3-methylglutaryl coenzyme-A reductase (HMGR), an established rate-limiting enzyme in the eukaryotic mevalonate pathway, increased the production level of β-sesquiphellandrene by 1.25–1.60 fold. The highest amount achieved was 33 nM at 2 h post-induction. PMID:23300671

  8. Genetic structure and regulation of isoprene synthase in Poplar (Populus spp.).

    PubMed

    Vickers, Claudia E; Possell, Malcolm; Nicholas Hewitt, C; Mullineaux, Philip M

    2010-07-01

    Isoprene is a volatile 5-carbon hydrocarbon derived from the chloroplastic methylerythritol 2-C-methyl-D: -erythritol 4-phosphate isoprenoid pathway. In plants, isoprene emission is controlled by the enzyme isoprene synthase; however, there is still relatively little known about the genetics and regulation of this enzyme. Isoprene synthase gene structure was analysed in three poplar species. It was found that genes encoding stromal isoprene synthase exist as a small gene family, the members of which encode virtually identical proteins and are differentially regulated. Accumulation of isoprene synthase protein is developmentally regulated, but does not differ between sun and shade leaves and does not increase when heat stress is applied. Our data suggest that, in mature leaves, isoprene emission rates are primarily determined by substrate (dimethylallyl diphosphate, DMADP) availability. In immature leaves, where isoprene synthase levels are variable, emission levels are also influenced by the amount of isoprene synthase protein. No thylakoid isoforms could be identified in Populus alba or in Salix babylonica. Together, these data show that control of isoprene emission at the genetic level is far more complicated than previously assumed.

  9. Cross-talk between the cytosolic mevalonate and the plastidial methylerythritol phosphate pathways in tobacco bright yellow-2 cells.

    PubMed

    Hemmerlin, Andréa; Hoeffler, Jean-François; Meyer, Odile; Tritsch, Denis; Kagan, Isabelle A; Grosdemange-Billiard, Catherine; Rohmer, Michel; Bach, Thomas J

    2003-07-18

    In plants, two pathways are utilized for the synthesis of isopentenyl diphosphate, the universal precursor for isoprenoid biosynthesis. The key enzyme of the cytoplasmic mevalonic acid (MVA) pathway is 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGR). Treatment of Tobacco Bright Yellow-2 (TBY-2) cells by the HMGR-specific inhibitor mevinolin led to growth reduction and induction of apparent HMGR activity, in parallel to an increase in protein representing two HMGR isozymes. Maximum induction was observed at 24 h. 1-Deoxy-d-xylulose (DX), the dephosphorylated first precursor of the plastidial 2-C-methyl-d-erythritol 4-phosphate (MEP) pathway, complemented growth inhibition by mevinolin in the low millimolar concentration range. Furthermore, DX partially re-established feedback repression of mevinolin-induced HMGR activity. Incorporation studies with [1,1,1,4-2H4]DX showed that sterols, normally derived from MVA, in the presence of mevinolin are synthesized via the MEP pathway. Fosmidomycin, an inhibitor of 1-deoxy-d-xylulose-5-phosphate reductoisomerase, the second enzyme of the MEP pathway, was utilized to study the reverse complementation. Growth inhibition by fosmidomycin of TBY-2 cells could be partially overcome by MVA. Chemical complementation was further substantiated by incorporation of [2-13C]MVA into plastoquinone, representative of plastidial isoprenoids. Best rates of incorporation of exogenous stably labeled precursors were observed in the presence of both inhibitors, thereby avoiding internal isotope dilution.

  10. Design of novel ligands of CDP-methylerythritol kinase by mimicking direct protein-protein and solvent-mediated interactions.

    PubMed

    Giménez-Oya, Victor; Villacañas, Oscar; Obiol-Pardo, Cristian; Antolin-Llovera, Meritxell; Rubio-Martinez, Jaime; Imperial, Santiago

    2011-01-01

    The methylerythritol 4-phosphate (MEP) pathway for the biosynthesis of the isoprenoid universal building blocks (isopentenyl diphosphate (IPP) and dimethylallyl diphosphate (DMAPP)) is present in most of human pathogens and is absent in animals, turning it into a promising therapeutic druggable pathway. Two different strategies, a pharmacophore-directed virtual screening and a protein-protein interaction (PPI)-mimicking cyclic peptide were used to search for compounds that bind to the PPI surface of the 4-(cytidine 5-diphospho)-2C-methyl-D-erythritol kinase (CMK), which catalyzes the fourth step of the MEP pathway. A significant part of the pharmacophore hypothesis used in this study was designed by mimicking water-mediated PPI relevant in the CMK homodimer complex stabilization. After database search and with the aid of docking and molecular dynamics (MD) simulations, a 7H-furo[3,2-g]chromen-7-one derivative and a cyclic peptide were chosen as candidates to be ligands of CMK. Their binding affinities were measured using surface plasmon resonance (SPR) technology.

  11. Molecular Mechanism of Action of Antimalarial Benzoisothiazolones: Species-Selective Inhibitors of the Plasmodium spp. MEP Pathway enzyme, IspD

    PubMed Central

    Price, Kathryn E.; Armstrong, Christopher M.; Imlay, Leah S.; Hodge, Dana M.; Pidathala, C.; Roberts, Natalie J.; Park, Jooyoung; Mikati, Marwa; Sharma, Raman; Lawrenson, Alexandre S.; Tolia, Niraj H.; Berry, Neil G.; O’Neill, Paul M.; John, Audrey R. Odom

    2016-01-01

    The methylerythritol phosphate (MEP) pathway is an essential metabolic pathway found in malaria parasites, but absent in mammals, making it a highly attractive target for the discovery of novel and selective antimalarial therapies. Using high-throughput screening, we have identified 2-phenyl benzo[d]isothiazol-3(2H)-ones as species-selective inhibitors of Plasmodium spp. 2-C-methyl-D-erythritol-4-phosphate cytidyltransferase (IspD), the third catalytic enzyme of the MEP pathway. 2-Phenyl benzo[d]isothiazol-3(2H)-ones display nanomolar inhibitory activity against P. falciparum and P. vivax IspD and prevent the growth of P. falciparum in culture, with EC50 values below 400 nM. In silico modeling, along with enzymatic, genetic and crystallographic studies, have established a mechanism-of-action involving initial non-covalent recognition of inhibitors at the IspD binding site, followed by disulfide bond formation through attack of an active site cysteine residue on the benzo[d]isothiazol-3(2H)-one core. The species-selective inhibitory activity of these small molecules against Plasmodium spp. IspD and cultured parasites suggests they have potential as lead compounds in the pursuit of novel drugs to treat malaria. PMID:27857147

  12. Mutations in Escherichia coli aceE and ribB genes allow survival of strains defective in the first step of the isoprenoid biosynthesis pathway.

    PubMed

    Perez-Gil, Jordi; Uros, Eva Maria; Sauret-Güeto, Susanna; Lois, L Maria; Kirby, James; Nishimoto, Minobu; Baidoo, Edward E K; Keasling, Jay D; Boronat, Albert; Rodriguez-Concepcion, Manuel

    2012-01-01

    A functional 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway is required for isoprenoid biosynthesis and hence survival in Escherichia coli and most other bacteria. In the first two steps of the pathway, MEP is produced from the central metabolic intermediates pyruvate and glyceraldehyde 3-phosphate via 1-deoxy-D-xylulose 5-phosphate (DXP) by the activity of the enzymes DXP synthase (DXS) and DXP reductoisomerase (DXR). Because the MEP pathway is absent from humans, it was proposed as a promising new target to develop new antibiotics. However, the lethal phenotype caused by the deletion of DXS or DXR was found to be suppressed with a relatively high efficiency by unidentified mutations. Here we report that several mutations in the unrelated genes aceE and ribB rescue growth of DXS-defective mutants because the encoded enzymes allowed the production of sufficient DXP in vivo. Together, this work unveils the diversity of mechanisms that can evolve in bacteria to circumvent a blockage of the first step of the MEP pathway.

  13. Multi-Substrate Terpene Synthases: Their Occurrence and Physiological Significance

    PubMed Central

    Pazouki, Leila; Niinemets, Ülo

    2016-01-01

    Terpene synthases are responsible for synthesis of a large number of terpenes in plants using substrates provided by two distinct metabolic pathways, the mevalonate-dependent pathway that is located in cytosol and has been suggested to be responsible for synthesis of sesquiterpenes (C15), and 2-C-methyl-D-erythritol-4-phosphate pathway located in plastids and suggested to be responsible for the synthesis of hemi- (C5), mono- (C10), and diterpenes (C20). Recent advances in characterization of genes and enzymes responsible for substrate and end product biosynthesis as well as efforts in metabolic engineering have demonstrated existence of a number of multi-substrate terpene synthases. This review summarizes the progress in the characterization of such multi-substrate terpene synthases and suggests that the presence of multi-substrate use might have been significantly underestimated. Multi-substrate use could lead to important changes in terpene product profiles upon substrate profile changes under perturbation of metabolism in stressed plants as well as under certain developmental stages. We therefore argue that multi-substrate use can be significant under physiological conditions and can result in complicate modifications in terpene profiles. PMID:27462341

  14. Fruit carotenoid-deficient mutants in tomato reveal a function of the plastidial isopentenyl diphosphate isomerase (IDI1) in carotenoid biosynthesis.

    PubMed

    Pankratov, Ilya; McQuinn, Ryan; Schwartz, Jochanan; Bar, Einat; Fei, Zhangjun; Lewinsohn, Efraim; Zamir, Dani; Giovannoni, James J; Hirschberg, Joseph

    2016-10-01

    Isoprenoids consist of a large class of compounds that are present in all living organisms. They are derived from the 5C building blocks isopentenyl diphosphate (IDP) and its isomer dimethylallyl diphosphate (DMADP). In plants, IDP is synthesized in the cytoplasm from mevalonic acid via the MVA pathway, and in plastids from 2-C-methyl-d-erythritol-4-phosphate through the MEP pathway. The enzyme IDP isomerase (IDI) catalyzes the interconversion between IDP and DMADP. Most plants contain two IDI enzymes, the functions of which are characteristically compartmentalized in the cells. Carotenoids are isoprenoids that play essential roles in photosynthesis and provide colors to flowers and fruits. They are synthesized in the plastids via the MEP pathway. Fruits of Solanum lycopersicum (tomato) accumulate high levels of the red carotene lycopene. We have identified mutations in tomato that reduce overall carotenoid accumulation in fruits. Four alleles of a locus named FRUIT CAROTENOID DEFICIENT 1 (fcd1) were characterized. Map-based cloning of fcd1 indicated that this gene encodes the plastidial enzyme IDI1. Lack of IDI1 reduced the concentration of carotenoids in fruits, flowers and cotyledons, but not in mature leaves. These results indicate that the plastidial IDI plays an important function in carotenoid biosynthesis, thus highlighting its role in optimizing the ratio between IDP and DMADP as precursors for different downstream isoprenoid pathways.

  15. Jasmonate-induced biosynthesis of andrographolide in Andrographis paniculata.

    PubMed

    Sharma, Shiv Narayan; Jha, Zenu; Sinha, Rakesh Kumar; Geda, Arvind Kumar

    2015-02-01

    Andrographolide is a prominent secondary metabolite found in Andrographis paniculata that exhibits enormous pharmacological effects. In spite of immense value, the normal biosynthesis of andrographolide results in low amount of the metabolite. To induce the biosynthesis of andrographolide, we attempted elicitor-induced activation of andrographolide biosynthesis in cell cultures of A. paniculata. This was carried out by using methyl jasmonate (MeJA) as an elicitor. Among the various concentrations of MeJA tested at different time periods, 5 µM MeJA yielded 5.25 times more andrographolide content after 24 h of treatment. The accumulation of andrographolide was correlated with the expression level of known regulatory genes (hmgs, hmgr, dxs, dxr, isph and ggps) of mevalonic acid (MVA) and 2-C-methyl-d-erythritol-4-phosphate (MEP) pathways. These results established the involvement of MeJA in andrographolide biosynthesis by inducing the transcription of its biosynthetic pathways genes. The coordination of isph, ggps and hmgs expression highly influenced the andrographolide biosynthesis.

  16. Nonmevalonate terpene biosynthesis enzymes as antiinfective drug targets: substrate synthesis and high-throughput screening methods.

    PubMed

    Illarionova, Victoria; Kaiser, Johannes; Ostrozhenkova, Elena; Bacher, Adelbert; Fischer, Markus; Eisenreich, Wolfgang; Rohdich, Felix

    2006-11-10

    The nonmevalonate isoprenoid pathway is an established target for antiinfective drug development. This paper describes high-throughput methods for the screening of 2C-methyl-D-erythritol synthase (IspC protein), 4-diphosphocytidyl-2C-methyl-D-erythritol synthase (IspD protein), 4-diphosphocytidyl-2C-methyl-D-erythritol kinase (IspE protein), and 2C-methyl-D-erythritol 2,4-cyclodiphosphate synthase (IspF protein) against large compound libraries. The assays use up to three auxiliary enzymes. They are all monitored photometrically at 340 nm and are robust as documented by Z-factors of >or=0.86. 13C NMR assays designed for hit verification via direct detection of the primary reaction product are also described. Enzyme-assisted methods for the preparation, on a multigram scale, of isoprenoid biosynthesis intermediates required as substrates for these assays are reported. Notably, these methods enable the introduction of single or multiple 13C labels as required for NMR-monitored assays. The preparation of 4-diphosphosphocytidyl-2C-methyl-D-erythritol 2-phosphate in multigram quantities is described for the first time.

  17. Osh4p exchanges sterols for phosphatidylinositol 4-phosphate between lipid bilayers

    PubMed Central

    de Saint-Jean, Maud; Delfosse, Vanessa; Douguet, Dominique; Chicanne, Gaëtan; Payrastre, Bernard; Bourguet, William

    2011-01-01

    Osh/Orp proteins transport sterols between organelles and are involved in phosphoinositide metabolism. The link between these two aspects remains elusive. Using novel assays, we address the influence of membrane composition on the ability of Osh4p/Kes1p to extract, deliver, or transport dehydroergosterol (DHE). Surprisingly, phosphatidylinositol 4-phosphate (PI(4)P) specifically inhibited DHE extraction because PI(4)P was itself efficiently extracted by Osh4p. We solve the structure of the Osh4p–PI(4)P complex and reveal how Osh4p selectively substitutes PI(4)P for sterol. Last, we show that Osh4p quickly exchanges DHE for PI(4)P and, thereby, can transport these two lipids between membranes along opposite routes. These results suggest a model in which Osh4p transports sterol from the ER to late compartments pinpointed by PI(4)P and, in turn, transports PI(4)P backward. Coupled to PI(4)P metabolism, this transport cycle would create sterol gradients. Because the residues that recognize PI(4)P are conserved in Osh4p homologues, other Osh/Orp are potential sterol/phosphoinositol phosphate exchangers. PMID:22162133

  18. INTRACELLULAR TRANSPORT. Phosphatidylserine transport by ORP/Osh proteins is driven by phosphatidylinositol 4-phosphate.

    PubMed

    Moser von Filseck, Joachim; Čopič, Alenka; Delfosse, Vanessa; Vanni, Stefano; Jackson, Catherine L; Bourguet, William; Drin, Guillaume

    2015-07-24

    In eukaryotic cells, phosphatidylserine (PS) is synthesized in the endoplasmic reticulum (ER) but is highly enriched in the plasma membrane (PM), where it contributes negative charge and to specific recruitment of signaling proteins. This distribution relies on transport mechanisms whose nature remains elusive. Here, we found that the PS transporter Osh6p extracted phosphatidylinositol 4-phosphate (PI4P) and exchanged PS for PI4P between two membranes. We solved the crystal structure of Osh6p:PI4P complex and demonstrated that the transport of PS by Osh6p depends on PI4P recognition in vivo. Finally, we showed that the PI4P-phosphatase Sac1p, by maintaining a PI4P gradient at the ER/PM interface, drove PS transport. Thus, PS transport by oxysterol-binding protein-related protein (ORP)/oxysterol-binding homology (Osh) proteins is fueled by PI4P metabolism through PS/PI4P exchange cycles.

  19. Characterizing the Tumor Response to Treatment With Combretastatin A4 Phosphate

    SciTech Connect

    Salmon, Beth A.; Siemann, Dietmar W. . E-mail: siemadw@ufl.edu

    2007-05-01

    Purpose: To examine the pathophysiologic impact of treatment with combretastatin A4 phosphate (CA4P) in regions of tumors that ultimately either necrose or survive treatment with this agent. Methods and Materials: Proliferation, perfusion, vessel density, and expression of vascular endothelial growth factor (VEGF) were analyzed in the KHT tumor model after treatment with CA4P. Analyses were conducted in the whole tumor and the tumor periphery. Results: Perfusion in the tumor periphery decreased 4 h after treatment, but returned to baseline 20 h later. Whole-tumor perfusion also decreased 4 h after treatment, but did not return to baseline. Vessel density decreased in the tumor as a whole, but not in the tumor periphery. No significant effect on the expression of VEGF was observed, but a decrease in proliferation in the whole tumor and the periphery was noted. Conclusions: The present study shows that those areas of a tumor that survive treatment with CA4P are affected by CA4P exposure, though only transiently. The decrease in perfusion could negatively affect therapies utilizing the combination of CA4P and conventional anticancer agents by decreasing drug delivery and tissue oxygenation. These findings suggest that the timing of CA4P treatments when used in conjunction with conventional anticancer therapies should be considered carefully.

  20. An efficient synthetic strategy for obtaining 4-methoxy carbon isotope labeled combretastatin A-4 phosphate and other Z-combretastatins.

    PubMed

    Pettit, George R; Minardi, Mathew D; Hogan, Fiona; Price, Pat M

    2010-03-26

    Human cancer and other clinical trials under development employing combretastatin A-4 phosphate (1b, CA4P) should benefit from the availability of a [(11)C]-labeled derivative for positron emission tomography (PET). In order to obtain a suitable precursor for addition of a [(11)C]methyl group at the penultimate step, several new synthetic pathways to CA4P were evaluated. Geometrical isomerization (Z to E) proved to be a challenge, but it was overcome by development of a new CA4P synthesis suitable for 4-methoxy isotope labeling.

  1. TIE2-expressing macrophages limit the therapeutic efficacy of the vascular-disrupting agent combretastatin A4 phosphate in mice

    PubMed Central

    Welford, Abigail F.; Biziato, Daniela; Coffelt, Seth B.; Nucera, Silvia; Fisher, Matthew; Pucci, Ferdinando; Di Serio, Clelia; Naldini, Luigi; De Palma, Michele; Tozer, Gillian M.; Lewis, Claire E.

    2011-01-01

    Vascular-disrupting agents (VDAs) such as combretastatin A4 phosphate (CA4P) selectively disrupt blood vessels in tumors and induce tumor necrosis. However, tumors rapidly repopulate after treatment with such compounds. Here, we show that CA4P-induced vessel narrowing, hypoxia, and hemorrhagic necrosis in murine mammary tumors were accompanied by elevated tumor levels of the chemokine CXCL12 and infiltration by proangiogenic TIE2-expressing macrophages (TEMs). Inhibiting TEM recruitment to CA4P-treated tumors either by interfering pharmacologically with the CXCL12/CXCR4 axis or by genetically depleting TEMs in tumor-bearing mice markedly increased the efficacy of CA4P treatment. These data suggest that TEMs limit VDA-induced tumor injury and represent a potential target for improving the clinical efficacy of VDA-based therapies. PMID:21490397

  2. TIE2-expressing macrophages limit the therapeutic efficacy of the vascular-disrupting agent combretastatin A4 phosphate in mice.

    PubMed

    Welford, Abigail F; Biziato, Daniela; Coffelt, Seth B; Nucera, Silvia; Fisher, Matthew; Pucci, Ferdinando; Di Serio, Clelia; Naldini, Luigi; De Palma, Michele; Tozer, Gillian M; Lewis, Claire E

    2011-05-01

    Vascular-disrupting agents (VDAs) such as combretastatin A4 phosphate (CA4P) selectively disrupt blood vessels in tumors and induce tumor necrosis. However, tumors rapidly repopulate after treatment with such compounds. Here, we show that CA4P-induced vessel narrowing, hypoxia, and hemorrhagic necrosis in murine mammary tumors were accompanied by elevated tumor levels of the chemokine CXCL12 and infiltration by proangiogenic TIE2-expressing macrophages (TEMs). Inhibiting TEM recruitment to CA4P-treated tumors either by interfering pharmacologically with the CXCL12/CXCR4 axis or by genetically depleting TEMs in tumor-bearing mice markedly increased the efficacy of CA4P treatment. These data suggest that TEMs limit VDA-induced tumor injury and represent a potential target for improving the clinical efficacy of VDA-based therapies.

  3. Over-expression of DXS gene enhances terpenoidal secondary metabolite accumulation in rose-scented geranium and Withania somnifera: active involvement of plastid isoprenogenic pathway in their biosynthesis.

    PubMed

    Jadaun, Jyoti Singh; Sangwan, Neelam S; Narnoliya, Lokesh K; Singh, Neha; Bansal, Shilpi; Mishra, Bhawana; Sangwan, Rajender Singh

    2017-04-01

    Rose-scented geranium (Pelargonium spp.) is one of the most important aromatic plants and is well known for its diverse perfumery uses. Its economic importance is due to presence of fragrance rich essential oil in its foliage. The essential oil is a mixture of various volatile phytochemicals which are mainly terpenes (isoprenoids) in nature. In this study, on the geranium foliage genes related to isoprenoid biosynthesis (DXS, DXR and HMGR) were isolated, cloned and confirmed by sequencing. Further, the first gene of 2-C-methyl-d-erythritol-4-phosphate (MEP) pathway, 1-deoxy-d-xylulose-5-phosphate synthase (GrDXS), was made full length by using rapid amplification of cDNA ends strategy. GrDXS contained a 2157 bp open reading frame that encoded a polypeptide of 792 amino acids having calculated molecular weight 77.5 kDa. This study is first report on heterologous expression and kinetic characterization of any gene from this economically important plant. Expression analysis of these genes was performed in different tissues as well as at different developmental stages of leaves. In response to external elicitors, such as methyl jasmonate, salicylic acid, light and wounding, all the three genes showed differential expression profiles. Further GrDXS was over expressed in the homologous (rose-scented geranium) as well as in heterologous (Withania somnifera) plant systems through genetic transformation approach. The over-expression of GrDXS led to enhanced secondary metabolites production (i.e. essential oil in rose-scented geranium and withanolides in W. somnifera). To the best of our knowledge, this is the first report showing the expression profile of the three genes related to isoprenoid biosynthesis pathways operated in rose-scented geranium as well as functional characterization study of any gene from rose-scented geranium through a genetic transformation system.

  4. Expression of 3-hydroxy-3-methylglutaryl-CoA reductase, p-hydroxybenzoate-m-geranyltransferase and genes of phenylpropanoid pathway exhibits positive correlation with shikonins content in arnebia [Arnebia euchroma (Royle) Johnston

    PubMed Central

    2010-01-01

    Background Geranyl pyrophosphate (GPP) and p-hydroxybenzoate (PHB) are the basic precursors involved in shikonins biosynthesis. GPP is derived from mevalonate (MVA) and/or 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway(s), depending upon the metabolite and the plant system under consideration. PHB, however, is synthesized by only phenylpropanoid (PP) pathway. GPP and PHB are central moieties to yield shikonins through the synthesis of m-geranyl-p-hydroxybenzoate (GHB). Enzyme p-hydroxybenzoate-m-geranyltransferase (PGT) catalyses the coupling of GPP and PHB to yield GHB. The present research was carried out in shikonins yielding plant arnebia [Arnebia euchroma (Royle) Johnston], wherein no molecular work has been reported so far. The objective of the work was to identify the preferred GPP synthesizing pathway for shikonins biosynthesis, and to determine the regulatory genes involved in the biosynthesis of GPP, PHB and GHB. Results A cell suspension culture-based, low and high shikonins production systems were developed to facilitate pathway identification and finding the regulatory gene. Studies with mevinolin and fosmidomycin, inhibitors of MVA and MEP pathway, respectively suggested MVA as a preferred route of GPP supply for shikonins biosynthesis in arnebia. Accordingly, genes of MVA pathway (eight genes), PP pathway (three genes), and GHB biosynthesis were cloned. Expression studies showed down-regulation of all the genes in response to mevinolin treatment, whereas gene expression was not influenced by fosmidomycin. Expression of all the twelve genes vis-à-vis shikonins content in low and high shikonins production system, over a period of twelve days at frequent intervals, identified critical genes of shikonins biosynthesis in arnebia. Conclusion A positive correlation between shikonins content and expression of 3-hydroxy-3-methylglutaryl-CoA reductase (AeHMGR) and AePGT suggested critical role played by these genes in shikonins biosynthesis. Higher

  5. Effector Vγ9Vδ2 T cells dominate the human fetal γδ T-cell repertoire.

    PubMed

    Dimova, Tanya; Brouwer, Margreet; Gosselin, Françoise; Tassignon, Joël; Leo, Oberdan; Donner, Catherine; Marchant, Arnaud; Vermijlen, David

    2015-02-10

    γδ T cells are unconventional T cells recognizing antigens via their γδ T-cell receptor (TCR) in a way that is fundamentally different from conventional αβ T cells. γδ T cells usually are divided into subsets according the type of Vγ and/or Vδ chain they express in their TCR. T cells expressing the TCR containing the γ-chain variable region 9 and the δ-chain variable region 2 (Vγ9Vδ2 T cells) are the predominant γδ T-cell subset in human adult peripheral blood. The current thought is that this predominance is the result of the postnatal expansion of cells expressing particular complementary-determining region 3 (CDR3) in response to encounters with microbes, especially those generating phosphoantigens derived from the 2-C-methyl-d-erythritol 4-phosphate pathway of isoprenoid synthesis. However, here we show that, rather than requiring postnatal microbial exposure, Vγ9Vδ2 T cells are the predominant blood subset in the second-trimester fetus, whereas Vδ1(+) and Vδ3(+) γδ T cells are present only at low frequencies at this gestational time. Fetal blood Vγ9Vδ2 T cells are phosphoantigen responsive and display very limited diversity in the CDR3 of the Vγ9 chain gene, where a germline-encoded sequence accounts for >50% of all sequences, in association with a prototypic CDR3δ2. Furthermore, these fetal blood Vγ9Vδ2 T cells are functionally preprogrammed (e.g., IFN-γ and granzymes-A/K), with properties of rapidly activatable innatelike T cells. Thus, enrichment for phosphoantigen-responsive effector T cells has occurred within the fetus before postnatal microbial exposure. These various characteristics have been linked in the mouse to the action of selecting elements and would establish a much stronger parallel between human and murine γδ T cells than is usually articulated.

  6. Biosynthesis of sesquiterpenes in grape berry exocarp of Vitis vinifera L.: evidence for a transport of farnesyl diphosphate precursors from plastids to the cytosol

    PubMed Central

    May, Bianca; Lange, B. Markus; Wüst, Matthias

    2013-01-01

    The participation of the mevalonic acid (MVA) and 1-deoxy-D-xylulose 5-phosphate/2-C-methyl-D-erythritol-4-phosphate (DOXP/MEP) pathways in sesquiterpene biosynthesis of grape berries was investigated. There is an increasing interest in this class of terpenoids, since the oxygenated sesquiterpene rotundone was identified as the peppery aroma impact compound in Australian Shiraz wines. To investigate precursor supply pathway utilization, in vivo feeding experiments were performed with the deuterium labeled, pathway specific, precursors [5,5-2H2]-1-deoxy-D-xylulose and [5,5-2H2]-mevalonic acid lactone. Head Space-Solid Phase Micro Extraction-Gas Chromatography-Mass Spectrometry (HS-SPME-GC-MS) analysis of the generated volatile metabolites demonstrated that de novo sesquiterpene biosynthesis is mainly located in the grape berry exocarp (skin), with no detectable activity in the mesocarp (flesh) of the Lemberger variety. Interestingly, precursors from both the (primarily) cytosolic MVA and plastidial DOXP/MEP pathways were incorporated into grape sesquiterpenes in the varieties Lemberger, Gewürztraminer and Syrah. Our labeling data provide evidence for a homogenous, cytosolic pool of precursors for sesquiterpene biosynthesis, indicating that a transport of precursors occurs mostly from plastids to the cytosol. The labeling patterns of the sesquiterpene germacrene D were in agreement with a cyclization mechanism analogous to that of a previously cloned enantioselective (R)-germacrene D synthase from Solidago canadensis. This observation was subsequently confirmed by enantioselective GC-MS analysis demonstrating the exclusive presence of (R)-germacrene D, and not the (S)-enantiomer, in grape berries. PMID:23954075

  7. Alteration of the flexible loop in 1-deoxy-D-xylulose-5-phosphate reductoisomerase boosts enthalpy-driven inhibition by fosmidomycin.

    PubMed

    Kholodar, Svetlana A; Tombline, Gregory; Liu, Juan; Tan, Zhesen; Allen, C Leigh; Gulick, Andrew M; Murkin, Andrew S

    2014-06-03

    1-Deoxy-d-xylulose-5-phosphate reductoisomerase (DXR), which catalyzes the first committed step in the 2-C-methyl-d-erythritol 4-phosphate pathway of isoprenoid biosynthesis used by Mycobacterium tuberculosis and other infectious microorganisms, is absent in humans and therefore an attractive drug target. Fosmidomycin is a nanomolar inhibitor of DXR, but despite great efforts, few analogues with comparable potency have been developed. DXR contains a strictly conserved residue, Trp203, within a flexible loop that closes over and interacts with the bound inhibitor. We report that while mutation to Ala or Gly abolishes activity, mutation to Phe and Tyr only modestly impacts kcat and Km. Moreover, pre-steady-state kinetics and primary deuterium kinetic isotope effects indicate that while turnover is largely limited by product release for the wild-type enzyme, chemistry is significantly more rate-limiting for W203F and W203Y. Surprisingly, these mutants are more sensitive to inhibition by fosmidomycin, resulting in Km/Ki ratios up to 19-fold higher than that of wild-type DXR. In agreement, isothermal titration calorimetry revealed that fosmidomycin binds up to 11-fold more tightly to these mutants. Most strikingly, mutation strongly tips the entropy-enthalpy balance of total binding energy from 50% to 75% and 91% enthalpy in W203F and W203Y, respectively. X-ray crystal structures suggest that these enthalpy differences may be linked to differences in hydrogen bond interactions involving a water network connecting fosmidomycin's phosphonate group to the protein. These results confirm the importance of the flexible loop, in particular Trp203, in ligand binding and suggest that improved inhibitor affinity may be obtained against the wild-type protein by introducing interactions with this loop and/or the surrounding structured water network.

  8. Metabolic engineering of Salmonella vaccine bacteria to boost human Vγ2Vδ2 T cell immunity.

    PubMed

    Workalemahu, Grefachew; Wang, Hong; Puan, Kia-Joo; Nada, Mohanad H; Kuzuyama, Tomohisa; Jones, Bradley D; Jin, Chenggang; Morita, Craig T

    2014-07-15

    Human Vγ2Vδ2 T cells monitor isoprenoid metabolism by recognizing foreign (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMBPP), a metabolite in the 2-C-methyl-D-erythritol-4-phosphate pathway used by most eubacteria and apicomplexan parasites, and self isopentenyl pyrophosphate, a metabolite in the mevalonate pathway used by humans. Whereas microbial infections elicit prolonged expansion of memory Vγ2Vδ2 T cells, immunization with prenyl pyrophosphates or aminobisphosphonates elicit short-term Vγ2Vδ2 expansion with rapid anergy and deletion upon subsequent immunizations. We hypothesized that a live, attenuated bacterial vaccine that overproduces HMBPP would elicit long-lasting Vγ2Vδ2 T cell immunity by mimicking a natural infection. Therefore, we metabolically engineered the avirulent aroA(-) Salmonella enterica serovar Typhimurium SL7207 strain by deleting the gene for LytB (the downstream enzyme from HMBPP) and functionally complementing for this loss with genes encoding mevalonate pathway enzymes. LytB(-) Salmonella SL7207 had high HMBPP levels, infected human cells as efficiently as did the wild-type bacteria, and stimulated large ex vivo expansions of Vγ2Vδ2 T cells from human donors. Importantly, vaccination of a rhesus monkey with live lytB(-) Salmonella SL7207 stimulated a prolonged expansion of Vγ2Vδ2 T cells without significant side effects or anergy induction. These studies provide proof-of-principle that metabolic engineering can be used to derive live bacterial vaccines that boost Vγ2Vδ2 T cell immunity. Similar engineering of metabolic pathways to produce lipid Ags or B vitamin metabolite Ags could be used to derive live bacterial vaccine for other unconventional T cells that recognize nonpeptide Ags.

  9. Divergent Regulation of Terpenoid Metabolism in the Trichomes of Wild and Cultivated Tomato Species1[W][OA

    PubMed Central

    Besser, Katrin; Harper, Andrea; Welsby, Nicholas; Schauvinhold, Ines; Slocombe, Stephen; Li, Yi; Dixon, Richard A.; Broun, Pierre

    2009-01-01

    The diversification of chemical production in glandular trichomes is important in the development of resistance against pathogens and pests in two species of tomato. We have used genetic and genomic approaches to uncover some of the biochemical and molecular mechanisms that underlie the divergence in trichome metabolism between the wild species Solanum habrochaites LA1777 and its cultivated relative, Solanum lycopersicum. LA1777 produces high amounts of insecticidal sesquiterpene carboxylic acids (SCAs), whereas cultivated tomatoes lack SCAs and are more susceptible to pests. We show that trichomes of the two species have nearly opposite terpenoid profiles, consisting mainly of monoterpenes and low levels of sesquiterpenes in S. lycopersicum and mainly of SCAs and very low monoterpene levels in LA1777. The accumulation patterns of these terpenoids are different during development, in contrast to the developmental expression profiles of terpenoid pathway genes, which are similar in the two species, but they do not correlate in either case with terpenoid accumulation. However, our data suggest that the accumulation of monoterpenes in S. lycopersicum and major sesquiterpenes in LA1777 are linked both genetically and biochemically. Metabolite analyses after targeted gene silencing, inhibitor treatments, and precursor feeding all show that sesquiterpene biosynthesis relies mainly on products from the plastidic 2-C-methyl-d-erythritol-4-phosphate pathway in LA1777 but less so in the cultivated species. Furthermore, two classes of sesquiterpenes produced by the wild species may be synthesized from distinct pools of precursors via cytosolic and plastidial cyclases. However, highly trichome-expressed sesquiterpene cyclase-like enzymes were ruled out as being involved in the production of major LA1777 sesquiterpenes. PMID:18997116

  10. Enhanced production of steviol glycosides in mycorrhizal plants: a concerted effect of arbuscular mycorrhizal symbiosis on transcription of biosynthetic genes.

    PubMed

    Mandal, Shantanu; Upadhyay, Shivangi; Singh, Ved Pal; Kapoor, Rupam

    2015-04-01

    Stevia rebaudiana (Bertoni) produces steviol glycosides (SGs)--stevioside (stev) and rebaudioside-A (reb-A) that are valued as low calorie sweeteners. Inoculation with arbuscular mycorrhizal fungi (AMF) augments SGs production, though the effect of this interaction on SGs biosynthesis has not been studied at molecular level. In this study transcription profiles of eleven key genes grouped under three stages of the SGs biosynthesis pathway were compared. The transcript analysis showed upregulation of genes encoding 2-C-methyl-D-erythritol-4-phosphate (MEP) pathway enzymes viz.,1-deoxy-D-xylulose 5-phospate synthase (DXS), 1-deoxy-D-xylulose 5-phospate reductoisomerase (DXR) and 2-C-methyl-D-erytrithol 2,4-cyclodiphosphate synthase (MDS) in mycorrhizal (M) plants. Zn and Mn are imperative for the expression of MDS and their enhanced uptake in M plants could be responsible for the increased transcription of MDS. Furthermore, in the second stage of SGs biosynthesis pathway, mycorrhization enhanced the transcription of copalyl diphosphate synthase (CPPS) and kaurenoic acid hydroxylase (KAH). Their expression is decisive for SGs biosynthesis as CPPS regulates flow of metabolites towards synthesis of kaurenoid precursors and KAH directs these towards steviol synthesis instead of gibberellins. In the third stage glucosylation of steviol to reb-A by four specific uridine diphosphate (UDP)-dependent glycosyltransferases (UGTs) occurs. While higher transcription of all the three characterized UGTs in M plants explains augmented production of SGs; higher transcript levels of UGT76G1, specifically improved reb-A to stev ratio implying increased sweetness. The work signifies that AM symbiosis upregulates the transcription of all eleven SGs biosynthesis genes as a result of improved nutrition and enhanced sugar concentration due to increased photosynthesis in M plants.

  11. Prerequisite for highly efficient isoprenoid production by cyanobacteria discovered through the over-expression of 1-deoxy-d-xylulose 5-phosphate synthase and carbon allocation analysis.

    PubMed

    Kudoh, Kai; Kawano, Yusuke; Hotta, Shingo; Sekine, Midori; Watanabe, Takafumi; Ihara, Masaki

    2014-07-01

    Cyanobacteria have recently been receiving considerable attention owing to their potential as photosynthetic producers of biofuels and biomaterials. Here, we focused on the production of isoprenoids by cyanobacteria, and aimed to provide insight into metabolic engineering design. To this end, we examined the over-expression of a key enzyme in 2-C-methyl-d-erythritol 4-phosphate (MEP) pathway, 1-deoxy-d-xylulose 5-phosphate synthase (DXS) in the cyanobacterium Synechocystis sp. PCC6803. In the DXS-over-expression strain (Dxs_ox), the mRNA and protein levels of DXS were 4-times and 1.5-times the levels in the wild-type (WT) strain, respectively. The carotenoid content of the Dxs_ox strain (8.4 mg/g dry cell weight [DCW]) was also up to 1.5-times higher than that in the WT strain (5.6 mg/g DCW), whereas the glycogen content dramatically decreased to an undetectable level. These observations suggested that the carotenoid content in the Dxs_ox strain was increased by consuming glycogen, which is a C-storage compound in cyanobacteria. We also quantified the total sugar (145 and 104 mg/g DCW), total fatty acids (31 and 24 mg/g DCW) and total protein (200 and 240 mg/g DCW) content in the WT and Dxs_ox strains, respectively, which were much higher than the carotenoid content. In particular, approximately 54% of the proteins were phycobiliproteins. This study demonstrated the major destinations of carbon flux in cyanobacteria, and provided important insights into metabolic engineering. Target yield can be improved through optimization of gene expression, the DXS protein stabilization, cell propagation depression and restriction of storage compound synthesis.

  12. Comparative Transcriptomics Unravel Biochemical Specialization of Leaf Tissues of Stevia for Diterpenoid Production1

    PubMed Central

    Kim, Mi Jung; Jin, Jingjing; Zheng, Junshi

    2015-01-01

    Stevia (Stevia rebaudiana) produces not only a group of diterpenoid glycosides known as steviol glycosides (SGs), but also other labdane-type diterpenoids that may be spatially separated from SGs. However, their biosynthetic routes and spatial distribution in leaf tissues have not yet been elucidated. Here, we integrate metabolome and transcriptome analyses of Stevia to explore the biosynthetic capacity of leaf tissues for diterpenoid metabolism. Tissue-specific chemical analyses confirmed that SGs were accumulated in leaf cells but not in trichomes. On the other hand, Stevia leaf trichomes stored other labdane-type diterpenoids such as oxomanoyl oxide and agatholic acid. RNA sequencing analyses from two different tissues of Stevia provided a comprehensive overview of dynamic metabolic activities in trichomes and leaf without trichomes. These metabolite-guided transcriptomics and phylogenetic and gene expression analyses clearly identified specific gene members encoding enzymes involved in the 2-C-methyl-d-erythritol 4-phosphate pathway and the biosynthesis of steviol or other labdane-type diterpenoids. Additionally, our RNA sequencing analysis uncovered copalyl diphosphate synthase (SrCPS) and kaurene synthase1 (SrKS1) homologs, SrCPS2 and KS-like (SrKSL), which were specifically expressed in trichomes. In vitro and in planta assays showed that unlike SrCPS and SrKS1, SrCPS2 synthesized labda-13-en-8-ol diphosphate and successively catalyzed the formation of manoyl oxide and epi-manoyl oxide in combination with SrKSL. Our findings suggest that Stevia may have evolved to use distinct metabolic pathways to avoid metabolic interferences in leaf tissues for efficient production of diverse secondary metabolites. PMID:26438788

  13. Comparative Transcriptomics Unravel Biochemical Specialization of Leaf Tissues of Stevia for Diterpenoid Production.

    PubMed

    Kim, Mi Jung; Jin, Jingjing; Zheng, Junshi; Wong, Limsoon; Chua, Nam-Hai; Jang, In-Cheol

    2015-12-01

    Stevia (Stevia rebaudiana) produces not only a group of diterpenoid glycosides known as steviol glycosides (SGs), but also other labdane-type diterpenoids that may be spatially separated from SGs. However, their biosynthetic routes and spatial distribution in leaf tissues have not yet been elucidated. Here, we integrate metabolome and transcriptome analyses of Stevia to explore the biosynthetic capacity of leaf tissues for diterpenoid metabolism. Tissue-specific chemical analyses confirmed that SGs were accumulated in leaf cells but not in trichomes. On the other hand, Stevia leaf trichomes stored other labdane-type diterpenoids such as oxomanoyl oxide and agatholic acid. RNA sequencing analyses from two different tissues of Stevia provided a comprehensive overview of dynamic metabolic activities in trichomes and leaf without trichomes. These metabolite-guided transcriptomics and phylogenetic and gene expression analyses clearly identified specific gene members encoding enzymes involved in the 2-C-methyl-d-erythritol 4-phosphate pathway and the biosynthesis of steviol or other labdane-type diterpenoids. Additionally, our RNA sequencing analysis uncovered copalyl diphosphate synthase (SrCPS) and kaurene synthase1 (SrKS1) homologs, SrCPS2 and KS-like (SrKSL), which were specifically expressed in trichomes. In vitro and in planta assays showed that unlike SrCPS and SrKS1, SrCPS2 synthesized labda-13-en-8-ol diphosphate and successively catalyzed the formation of manoyl oxide and epi-manoyl oxide in combination with SrKSL. Our findings suggest that Stevia may have evolved to use distinct metabolic pathways to avoid metabolic interferences in leaf tissues for efficient production of diverse secondary metabolites.

  14. Biosynthesis of sesquiterpenes in grape berry exocarp of Vitis vinifera L.: evidence for a transport of farnesyl diphosphate precursors from plastids to the cytosol.

    PubMed

    May, Bianca; Lange, B Markus; Wüst, Matthias

    2013-11-01

    The participation of the mevalonic acid (MVA) and 1-deoxy-d-xylulose 5-phosphate/2-C-methyl-d-erythritol-4-phosphate (DOXP/MEP) pathways in sesquiterpene biosynthesis of grape berries was investigated. There is an increasing interest in this class of terpenoids, since the oxygenated sesquiterpene rotundone was identified as the peppery aroma impact compound in Australian Shiraz wines. To investigate precursor supply pathway utilization, in vivo feeding experiments were performed with the deuterium labeled, pathway specific, precursors [5,5-(2)H2]-1-deoxy-d-xylulose and [5,5-(2)H2]-mevalonic acid lactone. Head Space-Solid Phase Micro Extraction-Gas Chromatography-Mass Spectrometry (HS-SPME-GC-MS) analysis of the generated volatile metabolites demonstrated that de novo sesquiterpene biosynthesis is mainly located in the grape berry exocarp (skin), with no detectable activity in the mesocarp (flesh) of the Lemberger variety. Interestingly, precursors from both the (primarily) cytosolic MVA and plastidial DOXP/MEP pathways were incorporated into grape sesquiterpenes in the varieties Lemberger, Gewürztraminer and Syrah. Our labeling data provide evidence for a homogenous, cytosolic pool of precursors for sesquiterpene biosynthesis, indicating that a transport of precursors occurs mostly from plastids to the cytosol. The labeling patterns of the sesquiterpene germacrene D were in agreement with a cyclization mechanism analogous to that of a previously cloned enantioselective (R)-germacrene D synthase from Solidago canadensis. This observation was subsequently confirmed by enantioselective GC-MS analysis demonstrating the exclusive presence of (R)-germacrene D, and not the (S)-enantiomer, in grape berries.

  15. De novo assembly and transcriptome analysis of the rubber tree (Hevea brasiliensis) and SNP markers development for rubber biosynthesis pathways.

    PubMed

    Mantello, Camila Campos; Cardoso-Silva, Claudio Benicio; da Silva, Carla Cristina; de Souza, Livia Moura; Scaloppi Junior, Erivaldo José; de Souza Gonçalves, Paulo; Vicentini, Renato; de Souza, Anete Pereira

    2014-01-01

    Hevea brasiliensis (Willd. Ex Adr. Juss.) Muell.-Arg. is the primary source of natural rubber that is native to the Amazon rainforest. The singular properties of natural rubber make it superior to and competitive with synthetic rubber for use in several applications. Here, we performed RNA sequencing (RNA-seq) of H. brasiliensis bark on the Illumina GAIIx platform, which generated 179,326,804 raw reads on the Illumina GAIIx platform. A total of 50,384 contigs that were over 400 bp in size were obtained and subjected to further analyses. A similarity search against the non-redundant (nr) protein database returned 32,018 (63%) positive BLASTx hits. The transcriptome analysis was annotated using the clusters of orthologous groups (COG), gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Pfam databases. A search for putative molecular marker was performed to identify simple sequence repeats (SSRs) and single nucleotide polymorphisms (SNPs). In total, 17,927 SSRs and 404,114 SNPs were detected. Finally, we selected sequences that were identified as belonging to the mevalonate (MVA) and 2-C-methyl-D-erythritol 4-phosphate (MEP) pathways, which are involved in rubber biosynthesis, to validate the SNP markers. A total of 78 SNPs were validated in 36 genotypes of H. brasiliensis. This new dataset represents a powerful information source for rubber tree bark genes and will be an important tool for the development of microsatellites and SNP markers for use in future genetic analyses such as genetic linkage mapping, quantitative trait loci identification, investigations of linkage disequilibrium and marker-assisted selection.

  16. Bisphosphonate Inhibitors Reveal a Large Elasticity of Plastidic Isoprenoid Synthesis Pathway in Isoprene-Emitting Hybrid Aspen1

    PubMed Central

    2015-01-01

    Recently, a feedback inhibition of the chloroplastic 1-deoxy-d-xylulose 5-phosphate (DXP)/2-C-methyl-d-erythritol 4-phosphate (MEP) pathway of isoprenoid synthesis by end products dimethylallyl diphosphate (DMADP) and isopentenyl diphosphate (IDP) was postulated, but the extent to which DMADP and IDP can build up is not known. We used bisphosphonate inhibitors, alendronate and zoledronate, that inhibit the consumption of DMADP and IDP by prenyltransferases to gain insight into the extent of end product accumulation and possible feedback inhibition in isoprene-emitting hybrid aspen (Populus tremula × Populus tremuloides). A kinetic method based on dark release of isoprene emission at the expense of substrate pools accumulated in light was used to estimate the in vivo pool sizes of DMADP and upstream metabolites. Feeding with fosmidomycin, an inhibitor of DXP reductoisomerase, alone or in combination with bisphosphonates was used to inhibit carbon input into DXP/MEP pathway or both input and output. We observed a major increase in pathway intermediates, 3- to 4-fold, upstream of DMADP in bisphosphonate-inhibited leaves, but the DMADP pool was enhanced much less, 1.3- to 1.5-fold. In combined fosmidomycin/bisphosphonate treatment, pathway intermediates accumulated, reflecting cytosolic flux of intermediates that can be important under strong metabolic pull in physiological conditions. The data suggested that metabolites accumulated upstream of DMADP consist of phosphorylated intermediates and IDP. Slow conversion of the huge pools of intermediates to DMADP was limited by reductive energy supply. These data indicate that the DXP/MEP pathway is extremely elastic, and the presence of a significant pool of phosphorylated intermediates provides an important valve for fine tuning the pathway flux. PMID:25926480

  17. Indirect Stimulation of Human Vγ2Vδ2 T cells Through Alterations in Isoprenoid Metabolism1

    PubMed Central

    Wang, Hong; Sarikonda, Ghanashyam; Puan, Kia-Joo; Tanaka, Yoshimasa; Feng, Ju; Giner, José-Luis; Cao, Rong; Mönkkönen, Jukka; Oldfield, Eric; Morita, Craig T.

    2011-01-01

    Human Vγ2Vδ2 T cells monitor isoprenoid metabolism by recognizing (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMBPP), an intermediate in the 2-C-methyl-D-erythritol-4-phosphate pathway used by microbes, and isopentenyl pyrophosphate (IPP), an intermediate in the mevalonate pathway used by humans. Aminobisphosphonates and alkylamines indirectly stimulate Vγ2Vδ2 cells by inhibiting farnesyl diphosphate synthase (FDPS) in the mevalonate pathway, thereby increasing IPP/ApppI that directly stimulate. In this study, we further characterize stimulation by these compounds, and define pathways used by new classes of compounds. Consistent with FDPS inhibition, stimulation of Vγ2Vδ2 cells by aminobisphosphonates and alkylamines was much more sensitive to statin inhibition than stimulation by prenyl pyrophosphates. However, the continuous presence of aminobisphosphonates was toxic for T cells, and blocked their proliferation. Aminobisphosphonate stimulation was rapid and prolonged, independent of known antigen presenting molecules, and resistant to fixation. New classes of stimulatory compounds–mevalonate, the alcohol of HMBPP, and alkenyl phosphonates–likely stimulate differently. Mevalonate, a rate-limiting metabolite, appears to enter cells to increase IPP levels whereas the alcohol of HMBPP and alkenyl phosphonates are directly recognized. The critical chemical feature of bisphosphonates is the amino moiety, because its loss switched aminobisphosphonates to direct antigens. Transfection of APC with siRNA downregulating FDPS rendered them stimulatory for Vγ2Vδ2 cells, and increased cellular IPP. siRNAs for isopentenyl diphosphate isomerase functioned similarly. Our results show that a variety of manipulations affecting isoprenoid metabolism lead to stimulation of Vγ2Vδ2 T cells and that pulsing aminobisphosphonates would be more effective for the ex vivo expansion of Vγ2Vδ2 T cells for adoptive cancer immunotherapy. PMID:22013129

  18. Transcriptome Sequencing and Expression Analysis of Terpenoid Biosynthesis Genes in Litsea cubeba

    PubMed Central

    Han, Xiao-Jiao; Wang, Yang-Dong; Chen, Yi-Cun; Lin, Li-Yuan; Wu, Qing-Ke

    2013-01-01

    Background Aromatic essential oils extracted from fresh fruits of Litsea cubeba (Lour.) Pers., have diverse medical and economic values. The dominant components in these essential oils are monoterpenes and sesquiterpenes. Understanding the molecular mechanisms of terpenoid biosynthesis is essential for improving the yield and quality of terpenes. However, the 40 available L. cubeba nucleotide sequences in the public databases are insufficient for studying the molecular mechanisms. Thus, high-throughput transcriptome sequencing of L. cubeba is necessary to generate large quantities of transcript sequences for the purpose of gene discovery, especially terpenoid biosynthesis related genes. Results Using Illumina paired-end sequencing, approximately 23.5 million high-quality reads were generated. De novo assembly yielded 68,648 unigenes with an average length of 834 bp. A total of 38,439 (56%) unigenes were annotated for their functions, and 35,732 and 25,806 unigenes could be aligned to the GO and COG database, respectively. By searching against the Kyoto Encyclopedia of Genes and Genomes Pathway database (KEGG), 16,130 unigenes were assigned to 297 KEGG pathways, and 61 unigenes, which contained the mevalonate and 2-C-methyl-D-erythritol 4-phosphate pathways, could be related to terpenoid backbone biosynthesis. Of the 12,963 unigenes, 285 were annotated to the terpenoid pathways using the PlantCyc database. Additionally, 14 terpene synthase genes were identified from the transcriptome. The expression patterns of the 16 genes related to terpenoid biosynthesis were analyzed by RT-qPCR to explore their putative functions. Conclusion RNA sequencing was effective in identifying a large quantity of sequence information. To our knowledge, this study is the first exploration of the L. cubeba transcriptome, and the substantial amount of transcripts obtained will accelerate the understanding of the molecular mechanisms of essential oils biosynthesis. The results may help

  19. Bisphosphonate inhibitors reveal a large elasticity of plastidic isoprenoid synthesis pathway in isoprene-emitting hybrid aspen.

    PubMed

    Rasulov, Bahtijor; Talts, Eero; Kännaste, Astrid; Niinemets, Ülo

    2015-06-01

    Recently, a feedback inhibition of the chloroplastic 1-deoxy-D-xylulose 5-phosphate (DXP)/2-C-methyl-D-erythritol 4-phosphate (MEP) pathway of isoprenoid synthesis by end products dimethylallyl diphosphate (DMADP) and isopentenyl diphosphate (IDP) was postulated, but the extent to which DMADP and IDP can build up is not known. We used bisphosphonate inhibitors, alendronate and zoledronate, that inhibit the consumption of DMADP and IDP by prenyltransferases to gain insight into the extent of end product accumulation and possible feedback inhibition in isoprene-emitting hybrid aspen (Populus tremula × Populus tremuloides). A kinetic method based on dark release of isoprene emission at the expense of substrate pools accumulated in light was used to estimate the in vivo pool sizes of DMADP and upstream metabolites. Feeding with fosmidomycin, an inhibitor of DXP reductoisomerase, alone or in combination with bisphosphonates was used to inhibit carbon input into DXP/MEP pathway or both input and output. We observed a major increase in pathway intermediates, 3- to 4-fold, upstream of DMADP in bisphosphonate-inhibited leaves, but the DMADP pool was enhanced much less, 1.3- to 1.5-fold. In combined fosmidomycin/bisphosphonate treatment, pathway intermediates accumulated, reflecting cytosolic flux of intermediates that can be important under strong metabolic pull in physiological conditions. The data suggested that metabolites accumulated upstream of DMADP consist of phosphorylated intermediates and IDP. Slow conversion of the huge pools of intermediates to DMADP was limited by reductive energy supply. These data indicate that the DXP/MEP pathway is extremely elastic, and the presence of a significant pool of phosphorylated intermediates provides an important valve for fine tuning the pathway flux.

  20. De Novo Assembly and Transcriptome Analysis of the Rubber Tree (Hevea brasiliensis) and SNP Markers Development for Rubber Biosynthesis Pathways

    PubMed Central

    Mantello, Camila Campos; Cardoso-Silva, Claudio Benicio; da Silva, Carla Cristina; de Souza, Livia Moura; Scaloppi Junior, Erivaldo José; de Souza Gonçalves, Paulo; Vicentini, Renato; de Souza, Anete Pereira

    2014-01-01

    Hevea brasiliensis (Willd. Ex Adr. Juss.) Muell.-Arg. is the primary source of natural rubber that is native to the Amazon rainforest. The singular properties of natural rubber make it superior to and competitive with synthetic rubber for use in several applications. Here, we performed RNA sequencing (RNA-seq) of H. brasiliensis bark on the Illumina GAIIx platform, which generated 179,326,804 raw reads on the Illumina GAIIx platform. A total of 50,384 contigs that were over 400 bp in size were obtained and subjected to further analyses. A similarity search against the non-redundant (nr) protein database returned 32,018 (63%) positive BLASTx hits. The transcriptome analysis was annotated using the clusters of orthologous groups (COG), gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Pfam databases. A search for putative molecular marker was performed to identify simple sequence repeats (SSRs) and single nucleotide polymorphisms (SNPs). In total, 17,927 SSRs and 404,114 SNPs were detected. Finally, we selected sequences that were identified as belonging to the mevalonate (MVA) and 2-C-methyl-D-erythritol 4-phosphate (MEP) pathways, which are involved in rubber biosynthesis, to validate the SNP markers. A total of 78 SNPs were validated in 36 genotypes of H. brasiliensis. This new dataset represents a powerful information source for rubber tree bark genes and will be an important tool for the development of microsatellites and SNP markers for use in future genetic analyses such as genetic linkage mapping, quantitative trait loci identification, investigations of linkage disequilibrium and marker-assisted selection. PMID:25048025

  1. Phosphatidylinositol 4-phosphate 5-kinase α is induced in ganglioside-stimulated brain astrocytes and contributes to inflammatory responses

    PubMed Central

    Kim, Bokyung; Yoon, Sarah; Kim, Yeon Joo; Liu, Tian; Woo, Joo Hong; Chwae, Yong-Joon; Joe, Eun-hye; Jou, Ilo

    2010-01-01

    In brain tissue, astrocytes play defensive roles in central nervous system integrity by mediating immune responses against pathological conditions. Type I phosphatidylinositol 4-phosphate 5-kinase α (PIP5Kα) that is responsible for production of phosphatidylinositol 4,5-bisphosphate (PI[4,5]P2) regulates many important cell functions at the cell surface. Here, we have examined whether PIP5Kα is associated with astrocyte inflammatory responses. Gangliosides are releasable from damaged cell membranes of neurons and capable of inducing inflammatory responses. We found that treatment of primary cultured astrocytes with gangliosides significantly enhanced PIP5Kα mRNA and protein expression levels. PI(4,5)P2 imaging using a fluorescent tubby (R332H) expression as a PI(4,5)P2-specific probe showed that ganglioside treatment increased PI(4,5)P2 level. Interestingly, microRNA-based PIP5Kα knockdown strongly reduced ganglioside-induced transcription of proinflammatory cytokines IL-1β and TNFα. PIP5Kα knockdown also suppressed ganglioside-induced phosphorylation and nuclear translocation of NF-κB and the degradation of IκB-α, indicating that PIP5Kα knockdown interfered with the ganglioside-activated NF-κB signaling. Together, these results suggest that PIP5Kα is a novel inflammatory mediator that undergoes upregulation and contributes to immune responses by facilitating NF-κB activation in ganglioside-stimulated astrocytes. PMID:20720456

  2. GOLPH3 Bridges Phosphatidylinositol-4- Phosphate and Actomyosin to Stretch and Shape the Golgi to Promote Budding

    PubMed Central

    Dippold, Holly C.; Ng, Michelle M.; Farber-Katz, Suzette E.; Lee, Sun-Kyung; Kerr, Monica L.; Peterman, Marshall C.; Sim, Ronald; Wiharto, Patricia A.; Galbraith, Kenneth A.; Madhavarapu, Swetha; Fuchs, Greg J.; Meerloo, Timo; Farquhar, Marilyn G.; Zhou, Huilin; Field, Seth J.

    2009-01-01

    SUMMARY Golgi membranes, from yeast to humans, are uniquely enriched in phosphatidylinositol-4-phosphate (PtdIns(4)P), although the role of this lipid remains poorly understood. Using a proteomic lipid binding screen, we identify the Golgi protein GOLPH3 (also called GPP34, GMx33, MIDAS, or yeast Vps74p) as a PtdIns(4)P-binding protein that depends upon PtdIns(4)P for its Golgi localization. We further show that GOLPH3 binds the unconventional myosin MYO18A, thus connecting the Golgi to F-actin. We demonstrate that this linkage is necessary for normal Golgi trafficking and morphology. The evidence suggests that GOLPH3 binds to PtdIns(4)P-rich trans-Golgi membranes and MYO18A conveying a tensile force required for efficient tubule and vesicle formation. Consequently, this tensile force stretches the Golgi into the extended ribbon observed by fluorescence microscopy and the familiar flattened form observed by electron microscopy. PMID:19837035

  3. Association of protein kinase Cmu with type II phosphatidylinositol 4-kinase and type I phosphatidylinositol-4-phosphate 5-kinase.

    PubMed

    Nishikawa, K; Toker, A; Wong, K; Marignani, P A; Johannes, F J; Cantley, L C

    1998-09-04

    Protein kinase Cmu (PKCmu), also named protein kinase D, is an unusual member of the PKC family that has a putative transmembrane domain and pleckstrin homology domain. This enzyme has a substrate specificity distinct from other PKC isoforms (Nishikawa, K., Toker, A., Johannes, F. J., Songyang, Z., and Cantley, L. C. (1997) J. Biol. Chem. 272, 952-960), and its mechanism of regulation is not yet clear. Here we show that PKCmu forms a complex in vivo with a phosphatidylinositol 4-kinase and a phosphatidylinositol-4-phosphate 5-kinase. A region of PKCmu between the amino-terminal transmembrane domain and the pleckstrin homology domain is shown to be involved in the association with the lipid kinases. Interestingly, a kinase-dead point mutant of PKCmu failed to associate with either lipid kinase activity, indicating that autophosphorylation may be required to expose the lipid kinase interaction domain. Furthermore, the subcellular distribution of the PKCmu-associated lipid kinases to the particulate fraction depends on the presence of the amino-terminal region of PKCmu including the predicted transmembrane region. These results suggest a novel model in which the non-catalytic region of PKCmu acts as a scaffold for assembly of enzymes involved in phosphoinositide synthesis at specific membrane locations.

  4. Nuclear pool of phosphatidylinositol 4 phosphate 5 kinase 1α is modified by polySUMO-2 during apoptosis

    SciTech Connect

    Chakrabarti, Rajarshi; Bhowmick, Debajit; Bhargava, Varsha; Bhar, Kaushik; Siddhanta, Anirban

    2013-09-20

    Highlights: •Nuclear pool of PIP5K is SUMOylated. •Enhancement of SUMOylated nuclear PIP5K during apoptosis. •Nuclear PIP5K is modified by polySUMO-1 during apoptosis. •Nuclear PIP5K is modified by polySUMO-2 chain during apoptosis. -- Abstract: Phosphatidylinositol 4 phosphate 5 kinase 1α (PIP5K) is mainly localized in the cytosol and plasma membrane. Studies have also indicated its prominent association with nuclear speckles. The exact nature of this nuclear pool of PIP5K is not clear. Using biochemical and microscopic techniques, we have demonstrated that the nuclear pool of PIP5K is modified by SUMO-1 in HEK-293 cells stably expressing PIP5K. Moreover, this SUMOylated pool of PIP5K increased during apoptosis. PolySUMO-2 chain conjugated PIP5K was detected by pull-down experiment using affinity-tagged RNF4, a polySUMO-2 binding protein, during late apoptosis.

  5. Phosphatidylinositol 4-phosphate in the Golgi apparatus regulates cell-cell adhesion and invasive cell migration in human breast cancer.

    PubMed

    Tokuda, Emi; Itoh, Toshiki; Hasegawa, Junya; Ijuin, Takeshi; Takeuchi, Yukiko; Irino, Yasuhiro; Fukumoto, Miki; Takenawa, Tadaomi

    2014-06-01

    Downregulation of cell-cell adhesion and upregulation of cell migration play critical roles in the conversion of benign tumors to aggressive invasive cancers. In this study, we show that changes in cell-cell adhesion and cancer cell migration/invasion capacity depend on the level of phosphatidylinositol 4-phosphate [PI(4)P] in the Golgi apparatus in breast cancer cells. Attenuating SAC1, a PI(4)P phosphatase localized in the Golgi apparatus, resulted in decreased cell-cell adhesion and increased cell migration in weakly invasive cells. In contrast, silencing phosphatidylinositol 4-kinase IIIβ, which generates PI(4)P in the Golgi apparatus, increased cell-cell adhesion and decreased invasion in highly invasive cells. Furthermore, a PI(4)P effector, Golgi phosphoprotein 3, was found to be involved in the generation of these phenotypes in a manner that depends on its PI(4)P-binding ability. Our results provide a new model for breast cancer cell progression in which progression is controlled by PI(4)P levels in the Golgi apparatus.

  6. Molecular basis of phosphatidylinositol 4-phosphate and ARF1 GTPase recognition by the FAPP1 pleckstrin homology (PH) domain.

    PubMed

    He, Ju; Scott, Jordan L; Heroux, Annie; Roy, Siddhartha; Lenoir, Marc; Overduin, Michael; Stahelin, Robert V; Kutateladze, Tatiana G

    2011-05-27

    Four-phosphate-adaptor protein 1 (FAPP1) regulates secretory transport from the trans-Golgi network (TGN) to the plasma membrane. FAPP1 is recruited to the Golgi through binding of its pleckstrin homology (PH) domain to phosphatidylinositol 4-phosphate (PtdIns(4)P) and a small GTPase ADP-ribosylation factor 1 (ARF1). Despite the critical role of FAPP1 in membrane trafficking, the molecular basis of its dual function remains unclear. Here, we report a 1.9 Å resolution crystal structure of the FAPP1 PH domain and detail the molecular mechanisms of the PtdIns(4)P and ARF1 recognition. The FAPP1 PH domain folds into a seven-stranded β-barrel capped by an α-helix at one edge, whereas the opposite edge is flanked by three loops and the β4 and β7 strands that form a lipid-binding pocket within the β-barrel. The ARF1-binding site is located on the outer side of the β-barrel as determined by NMR resonance perturbation analysis, mutagenesis, and measurements of binding affinities. The two binding sites have little overlap, allowing FAPP1 PH to associate with both ligands simultaneously and independently. Binding to PtdIns(4)P is enhanced in an acidic environment and is required for membrane penetration and tubulation activity of FAPP1, whereas the GTP-bound conformation of the GTPase is necessary for the interaction with ARF1. Together, these findings provide structural and biochemical insight into the multivalent membrane anchoring by the PH domain that may augment affinity and selectivity of FAPP1 toward the TGN membranes enriched in both PtdIns(4)P and GTP-bound ARF1.

  7. Synthesis of unsaturated phosphatidylinositol 4-phosphates and the effects of substrate unsaturation on SopB phosphatase activity.

    PubMed

    Furse, Samuel; Mak, LokHang; Tate, Edward W; Templer, Richard H; Ces, Oscar; Woscholski, Rüdiger; Gaffney, Piers R J

    2015-02-21

    In this paper evidence is presented that the fatty acid component of an inositide substrate affects the kinetic parameters of the lipid phosphatase Salmonella Outer Protein B (SopB). A succinct route was used to prepare the naturally occurring enantiomer of phosphatidylinositol 4-phosphate (PI-4-P) with saturated, as well as singly, triply and quadruply unsaturated, fatty acid esters, in four stages: (1) The enantiomers of 2,3:5,6-O-dicyclohexylidene-myo-inositol were resolved by crystallisation of their di(acetylmandelate) diastereoisomers. (2) The resulting diol was phosphorylated regio-selectively exclusively on the 1-O using the new reagent tri(2-cyanoethyl)phosphite. (3) With the 4-OH still unprotected, the glyceride was coupled using phosphate tri-ester methodology. (4) A final phosphorylation of the 4-O, followed by global deprotection under basic then acidic conditions, provided PI-4-P bearing a range of sn-1-stearoyl, sn-2-stearoyl, -oleoyl, -γ-linolenoyl and arachidonoyl, glycerides. Enzymological studies showed that the introduction of cis-unsaturated bonds has a measurable influence on the activity (relative Vmax) of SopB. Mono-unsaturated PI-4-P exhibited a five-fold higher activity, with a two-fold higher KM, over the saturated substrate, when presented in DOPC vesicles. Poly-unsaturated PI-4-P showed little further change with respect to the singly unsaturated species. This result, coupled with our previous report that saturated PI-4-P has much higher stored curvature elastic stress than PI, supports the hypothesis that the activity of inositide phosphatase SopB has a physical role in vivo.

  8. Local control of phosphatidylinositol 4-phosphate signaling in the Golgi apparatus by Vps74 and Sac1 phosphoinositide phosphatase

    PubMed Central

    Wood, Christopher S.; Hung, Chia-Sui; Huoh, Yu-San; Mousley, Carl J.; Stefan, Christopher J.; Bankaitis, Vytas; Ferguson, Kathryn M.; Burd, Christopher G.

    2012-01-01

    In the Golgi apparatus, lipid homeostasis pathways are coordinated with the biogenesis of cargo transport vesicles by phosphatidylinositol 4-kinases (PI4Ks) that produce phosphatidylinositol 4-phosphate (PtdIns4P), a signaling molecule that is recognized by downstream effector proteins. Quantitative analysis of the intra-Golgi distribution of a PtdIns4P reporter protein confirms that PtdIns4P is enriched on the trans-Golgi cisterna, but surprisingly, Vps74 (the orthologue of human GOLPH3), a PI4K effector required to maintain residence of a subset of Golgi proteins, is distributed with the opposite polarity, being most abundant on cis and medial cisternae. Vps74 binds directly to the catalytic domain of Sac1 (KD = 3.8 μM), the major PtdIns4P phosphatase in the cell, and PtdIns4P is elevated on medial Golgi cisternae in cells lacking Vps74 or Sac1, suggesting that Vps74 is a sensor of PtdIns4P level on medial Golgi cisternae that directs Sac1-mediated dephosphosphorylation of this pool of PtdIns4P. Consistent with the established role of Sac1 in the regulation of sphingolipid biosynthesis, complex sphingolipid homeostasis is perturbed in vps74Δ cells. Mutant cells lacking complex sphingolipid biosynthetic enzymes fail to properly maintain residence of a medial Golgi enzyme, and cells lacking Vps74 depend critically on complex sphingolipid biosynthesis for growth. The results establish additive roles of Vps74-mediated and sphingolipid-dependent sorting of Golgi residents. PMID:22553352

  9. Structural definition of the active site and catalytic mechanism of 3,4-dihydroxy-2-butanone-4-phosphate synthase.

    PubMed

    Liao, Der-Ing; Zheng, Ya-Jun; Viitanen, Paul V; Jordan, Douglas B

    2002-02-12

    X-ray crystal structures of L-3,4-dihydroxy-2-butanone-4-phosphate synthase from Magnaporthe grisea are reported for the E-SO(4)(2-), E-SO(4)(2-)-Mg(2+), E-SO(4)(2)(-)-Mn(2+), E-SO(4)(2)(-)-Mn(2+)-glycerol, and E-SO(4)(2)(-)-Zn(2+) complexes with resolutions that extend to 1.55, 0.98, 1.60, 1.16, and 1.00 A, respectively. Active-site residues of the homodimer are fully defined. The structures were used to model the substrate ribulose 5-phosphate in the active site with the phosphate group anchored at the sulfate site and the placement of the ribulose group guided by the glycerol site. The model includes two Mg(2+) cations that bind to the oxygen substituents of the C2, C3, C4, and phosphate groups of the substrate, the side chains of Glu37 and His153, and water molecules. The position of the metal cofactors and the substrate's phosphate group are further stabilized by an extensive hydrogen-bond and salt-bridge network. On the basis of their proximity to the substrate's reaction participants, the imidazole of an Asp99-His136 dyad from one subunit, the side chains of the Asp41, Cys66, and Glu174 residues from the other subunit, and Mg(2+)-activated water molecules are proposed to serve specific roles in the catalytic cycle as general acid-base functionalities. The model suggests that during the 1,2-shift step of the reaction, the substrate's C3 and C4 hydroxyl groups are cis to each other. A cis transition state is calculated to have an activation barrier that is 2 kcal/mol greater than that of the trans transition state in the absence of the enzyme.

  10. Structural definition of the active site and catalytic mechanism of 3,4-dihydroxy-2-butanone 4-phosphate synthase

    SciTech Connect

    Liao, D.-I.; Zheng, Y.-J.; Viitanen, P.V.; Jordan, D.B.

    2010-03-08

    X-ray crystal structures of L-3,4-dihydroxy-2-butanone-4-phosphate synthase from Magnaporthe grisea are reported for the E-SO{sub 4}{sup 2-}, E-{sub 4}{sup 2-}-Mg{sup 2+}, E-SO{sub 4}{sup 2-}-Mn{sup 2+}, E-SO{sub 4}{sup 2-}-Mn{sup 2+}-glycerol, and E-SO{sub 4}{sup 2-}-Zn{sup 2+} complexes with resolutions that extend to 1.55, 0.98, 1.60, 1.16, and 1.00 {angstrom}, respectively. Active-site residues of the homodimer are fully defined. The structures were used to model the substrate ribulose 5-phosphate in the active site with the phosphate group anchored at the sulfate site and the placement of the ribulose group guided by the glycerol site. The model includes two Mg{sup 2+} cations that bind to the oxygen substituents of the C2, C3, C4, and phosphate groups of the substrate, the side chains of Glu37 and His153, and water molecules. The position of the metal cofactors and the substrate's phosphate group are further stabilized by an extensive hydrogen-bond and salt-bridge network. On the basis of their proximity to the substrate's reaction participants, the imidazole of an Asp99-His136 dyad from one subunit, the side chains of the Asp41, Cys66, and Glu174 residues from the other subunit, and Mg{sup 2+}-activated water molecules are proposed to serve specific roles in the catalytic cycle as general acid-base functionalities. The model suggests that during the 1,2-shift step of the reaction, the substrate's C3 and C4 hydroxyl groups are cis to each other. A cis transition state is calculated to have an activation barrier that is 2 kcal/mol greater than that of the trans transition state in the absence of the enzyme.

  11. Eps15 homology domain 1-associated tubules contain phosphatidylinositol-4-phosphate and phosphatidylinositol-(4,5)-bisphosphate and are required for efficient recycling.

    PubMed

    Jović, Marko; Kieken, Fabien; Naslavsky, Naava; Sorgen, Paul L; Caplan, Steve

    2009-06-01

    The C-terminal Eps15 homology domain (EHD) 1/receptor-mediated endocytosis-1 protein regulates recycling of proteins and lipids from the recycling compartment to the plasma membrane. Recent studies have provided insight into the mode by which EHD1-associated tubular membranes are generated and the mechanisms by which EHD1 functions. Despite these advances, the physiological function of these striking EHD1-associated tubular membranes remains unknown. Nuclear magnetic resonance spectroscopy demonstrated that the Eps15 homology (EH) domain of EHD1 binds to phosphoinositides, including phosphatidylinositol-4-phosphate. Herein, we identify phosphatidylinositol-4-phosphate as an essential component of EHD1-associated tubules in vivo. Indeed, an EHD1 EH domain mutant (K483E) that associates exclusively with punctate membranes displayed decreased binding to phosphatidylinositol-4-phosphate and other phosphoinositides. Moreover, we provide evidence that although the tubular membranes to which EHD1 associates may be stabilized and/or enhanced by EHD1 expression, these membranes are, at least in part, pre-existing structures. Finally, to underscore the function of EHD1-containing tubules in vivo, we used a small interfering RNA (siRNA)/rescue assay. On transfection, wild-type, tubule-associated, siRNA-resistant EHD1 rescued transferrin and beta1 integrin recycling defects observed in EHD1-depleted cells, whereas expression of the EHD1 K483E mutant did not. We propose that phosphatidylinositol-4-phosphate is an essential component of EHD1-associated tubules that also contain phosphatidylinositol-(4,5)-bisphosphate and that these structures are required for efficient recycling to the plasma membrane.

  12. Studies on the nonmevalonate pathway to terpenes: The role of the GcpE (IspG) protein

    PubMed Central

    Hecht, Stefan; Eisenreich, Wolfgang; Adam, Petra; Amslinger, Sabine; Kis, Klaus; Bacher, Adelbert; Arigoni, Duilio; Rohdich, Felix

    2001-01-01

    Recombinant Escherichia coli cells engineered for the expression of the xylB gene in conjunction with genes of the nonmevalonate pathway were supplied with 13C-labeled 1-deoxy-d-xylulose. Cell extracts were analyzed directly by NMR spectroscopy. 13C-labeled 2C-methyl-d-erythritol 2,4-cyclodiphosphate was detected at high levels in cells expressing xylB, ispC, ispD, ispE, and ispF. The additional expression of the gcpE gene afforded 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate as an intermediate of the nonmevalonate pathway. Hypothetical mechanisms involving conserved cysteine residues are proposed for the enzymatic conversion of 2C-methyl-d-erythritol 2,4-cyclodiphosphate into 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate catalyzed by the GcpE protein. PMID:11752431

  13. Studies on the nonmevalonate pathway to terpenes: the role of the GcpE (IspG) protein.

    PubMed

    Hecht, S; Eisenreich, W; Adam, P; Amslinger, S; Kis, K; Bacher, A; Arigoni, D; Rohdich, F

    2001-12-18

    Recombinant Escherichia coli cells engineered for the expression of the xylB gene in conjunction with genes of the nonmevalonate pathway were supplied with (13)C-labeled 1-deoxy-D-xylulose. Cell extracts were analyzed directly by NMR spectroscopy. (13)C-labeled 2C-methyl-D-erythritol 2,4-cyclodiphosphate was detected at high levels in cells expressing xylB, ispC, ispD, ispE, and ispF. The additional expression of the gcpE gene afforded 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate as an intermediate of the nonmevalonate pathway. Hypothetical mechanisms involving conserved cysteine residues are proposed for the enzymatic conversion of 2C-methyl-D-erythritol 2,4-cyclodiphosphate into 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate catalyzed by the GcpE protein.

  14. Cloning and expression of IspDF from Mesorhizobium loti. Characterization of a bifunctional protein that catalyzes non-consecutive steps in the methylerythritol phosphate pathway.

    PubMed

    Testa, Charles A; Lherbet, Christian; Pojer, Florence; Noel, Joseph P; Poulter, C Dale

    2006-01-01

    Gram-negative bacteria, plant chloroplasts, green algae and some Gram-positive bacteria utilize the 2-C-methyl-d-erythritol phosphate (MEP) pathway for the biosynthesis of isoprenoids. IspD, ispE, and ispF encode the enzymes required to convert MEP to 2-C-methyl-d-erythritol 2,4-cyclodiphosphate (cMEDP) during the biosynthesis of isopentenyl diphosphate and dimethylallyl diphosphate in the MEP pathway. Upon analysis of the Mesorhizobium loti genome, ORF mll0395 showed homology to both ispD and ispF and appeared to encode a fusion protein. M. loti ispE was located elsewhere on the chromosome. Purified recombinant IspDF protein was mostly a homodimer, MW approximately 46 kDa/subunit. Incubation of IspDF with MEP, CTP, and ATP gave 4-diphosphocytidyl-2-C-methyl-d-erythritol (CDP-ME) as the only product. When Escherichia coli IspE protein was added to the incubation mixture, cMEDP was formed. In addition, M. loti ORF mll0395 complements lethal disruptions in both ispD and ispF in Salmonella typhimurium. These results indicate that IspDF is a bifunctional protein, which catalyzes the first and third steps in the conversion of MEP to cMEDP.

  15. Lenz-Majewski mutations in PTDSS1 affect phosphatidylinositol 4-phosphate metabolism at ER-PM and ER-Golgi junctions

    PubMed Central

    Sohn, Mira; Ivanova, Pavlina; Brown, H. Alex; Varnai, Peter; Kim, Yeun Ju; Balla, Tamas

    2016-01-01

    Lenz-Majewski syndrome (LMS) is a rare disease characterized by complex craniofacial, dental, cutaneous, and limb abnormalities combined with intellectual disability. Mutations in the PTDSS1 gene coding one of the phosphatidylserine (PS) synthase enzymes, PSS1, were described as causative in LMS patients. Such mutations render PSS1 insensitive to feedback inhibition by PS levels. Here we show that expression of mutant PSS1 enzymes decreased phosphatidylinositol 4-phosphate (PI4P) levels both in the Golgi and the plasma membrane (PM) by activating the Sac1 phosphatase and altered PI4P cycling at the PM. Conversely, inhibitors of PI4KA, the enzyme that makes PI4P in the PM, blocked PS synthesis and reduced PS levels by 50% in normal cells. However, mutant PSS1 enzymes alleviated the PI4P dependence of PS synthesis. Oxysterol-binding protein–related protein 8, which was recently identified as a PI4P-PS exchanger between the ER and PM, showed PI4P-dependent membrane association that was significantly decreased by expression of PSS1 mutant enzymes. Our studies reveal that PS synthesis is tightly coupled to PI4P-dependent PS transport from the ER. Consequently, PSS1 mutations not only affect cellular PS levels and distribution but also lead to a more complex imbalance in lipid homeostasis by disturbing PI4P metabolism. PMID:27044099

  16. Rhinovirus uses a phosphatidylinositol 4-phosphate/cholesterol counter-current for the formation of replication compartments at the ER-Golgi interface.

    PubMed

    Roulin, Pascal S; Lötzerich, Mark; Torta, Federico; Tanner, Lukas B; van Kuppeveld, Frank J M; Wenk, Markus R; Greber, Urs F

    2014-11-12

    Similar to other positive-strand RNA viruses, rhinovirus, the causative agent of the common cold, replicates on a web of cytoplasmic membranes, orchestrated by host proteins and lipids. The host pathways that facilitate the formation and function of the replication membranes and complexes are poorly understood. We show that rhinovirus replication depends on host factors driving phosphatidylinositol 4-phosphate (PI4P)-cholesterol counter-currents at viral replication membranes. Depending on the virus type, replication required phosphatidylinositol 4-kinase class 3beta (PI4K3b), cholesteryl-esterase hormone-sensitive lipase (HSL) or oxysterol-binding protein (OSBP)-like 1, 2, 5, 9, or 11 associated with lipid droplets, endosomes, or Golgi. Replication invariably required OSBP1, which shuttles cholesterol and PI4P between ER and Golgi at membrane contact sites. Infection also required ER-associated PI4P phosphatase Sac1 and phosphatidylinositol (PI) transfer protein beta (PITPb) shunting PI between ER-Golgi. These data support a PI4P-cholesterol counter-flux model for rhinovirus replication.

  17. Combretastatin-A4 phosphate improves the distribution and antitumor efficacy of albumin-bound paclitaxel in W256 breast carcinoma model

    PubMed Central

    Gao, Meng; Zhang, Dongjian; Jin, Qiaomei; Jiang, Cuihua; Wang, Cong; Li, Jindian; Peng, Fei; Huang, Dejian; Zhang, Jian; Song, Shaoli

    2016-01-01

    Nanomedicine holds great promise for fighting against malignant tumors. However, tumor elevated interstitial fluid pressure (IFP) seriously hinders convective transvascular and interstitial transport of nanomedicines and thus damages its antitumor efficacy. In this study, combretastatin-A4 phosphate (CA4P) was utilized to reduce tumor IFP, and thereby to improve the intratumoral distribution and antitumor efficacy of nanoparticle albumin-bound paclitaxel (nab-paclitaxel). IFP was measured using the wick-in-needle method in tumors growing subcutaneously pretreatment and posttreatment with a single intravenous injection of CA4P. The tracing method of iodine 131 isotope was used for biodistribution analysis of nab-paclitaxel. Liquid chromatography coupled with tandem mass spectrometry was used to detect the intratumoral concentration of paclitaxel. Magnetic resonance imaging was applied to monitor tumor volume and ratios of necrosis. The tumor IFP continued to decline gradually over time following CA4P treatment, reaching approximately 31% of the pretreatment value by 1 h posttreatment. Biodistribution data indicated that both 131I-nab-paclitaxel and paclitaxel exhibited higher tumor uptake in CA4P + 131I-nab-paclitaxel group compared with I131-nab-paclitaxel group. Nab-paclitaxel combined with CA4Pshowed significant tumor growth inhibition and higher tumor necrosis ratio relative to PBS, CA4P and nab-paclitaxel group, respectively. In conclusion, CA4P improved the intratumoral distribution and antitumor efficacy of nab-paclitaxel in W256 tumor-bearing rats. PMID:27531898

  18. ARC3, a chloroplast division factor, is a chimera of prokaryotic FtsZ and part of eukaryotic phosphatidylinositol-4-phosphate 5-kinase.

    PubMed

    Shimada, Hiroshi; Koizumi, Masato; Kuroki, Kouta; Mochizuki, Mariko; Fujimoto, Hitoshi; Ohta, Hiroyuki; Masuda, Tatsuru; Takamiya, Ken-ichiro

    2004-08-01

    The arc3 (accumulation and replication of chloroplast) mutant of Arabidopsis thaliana has a small number of abnormally large chloroplasts in the cell, suggesting that chloroplast division is arrested in the mutant and ARC3 has an important role in the initiation of chloroplast division. To elucidate the role of ARC3, first we identified the ARC3 gene, and determined the location of ARC3 protein during chloroplast division because the localization and spatial orientation of such division factors are vital for correct chloroplast division. Sequencing analysis showed that ARC3 was a fusion of the prokaryotic FtsZ and part of the eukaryotic phosphatidylinositol-4-phosphate 5-kinase (PIP5K) genes. The PIP5K-homologous region of ARC3 had no catalytic domain but a membrane-occupation-and-recognition-nexus (MORN) repeat motif. Immunofluorescence microscopy, Western blotting analysis and in vitro chloroplast import and protease protection assays revealed that ARC3 protein was soluble, and located on the outer surface of the chloroplast in a ring-like structure at the early stage of chloroplast division. Prokaryotes have one FtsZ as a gene for division but have no ARC3 counterparts, the chimera of FtsZ and PIP5K, suggesting that the ARC3 gene might have been generated from FtsZ as another division factor during the evolution of chloroplast by endosymbiosis.

  19. Protein Kinase D1 regulates focal adhesion dynamics and cell adhesion through Phosphatidylinositol-4-phosphate 5-kinase type-l γ

    PubMed Central

    Durand, Nisha; Bastea, Ligia I.; Long, Jason; Döppler, Heike; Ling, Kun; Storz, Peter

    2016-01-01

    Focal adhesions (FAs) are highly dynamic structures that are assembled and disassembled on a continuous basis. The balance between the two processes mediates various aspects of cell behavior, ranging from cell adhesion and spreading to directed cell migration. The turnover of FAs is regulated at multiple levels and involves a variety of signaling molecules and adaptor proteins. In the present study, we show that in response to integrin engagement, a subcellular pool of Protein Kinase D1 (PKD1) localizes to the FAs. PKD1 affects FAs by decreasing turnover and promoting maturation, resulting in enhanced cell adhesion. The effects of PKD1 are mediated through direct phosphorylation of FA-localized phosphatidylinositol-4-phosphate 5-kinase type-l γ (PIP5Klγ) at serine residue 448. This phosphorylation occurs in response to Fibronectin-RhoA signaling and leads to a decrease in PIP5Klγs’ lipid kinase activity and binding affinity for Talin. Our data reveal a novel function for PKD1 as a regulator of FA dynamics and by identifying PIP5Klγ as a novel PKD1 substrate provide mechanistic insight into this process. PMID:27775029

  20. Protein Kinase D1 regulates focal adhesion dynamics and cell adhesion through Phosphatidylinositol-4-phosphate 5-kinase type-l γ.

    PubMed

    Durand, Nisha; Bastea, Ligia I; Long, Jason; Döppler, Heike; Ling, Kun; Storz, Peter

    2016-10-24

    Focal adhesions (FAs) are highly dynamic structures that are assembled and disassembled on a continuous basis. The balance between the two processes mediates various aspects of cell behavior, ranging from cell adhesion and spreading to directed cell migration. The turnover of FAs is regulated at multiple levels and involves a variety of signaling molecules and adaptor proteins. In the present study, we show that in response to integrin engagement, a subcellular pool of Protein Kinase D1 (PKD1) localizes to the FAs. PKD1 affects FAs by decreasing turnover and promoting maturation, resulting in enhanced cell adhesion. The effects of PKD1 are mediated through direct phosphorylation of FA-localized phosphatidylinositol-4-phosphate 5-kinase type-l γ (PIP5Klγ) at serine residue 448. This phosphorylation occurs in response to Fibronectin-RhoA signaling and leads to a decrease in PIP5Klγs' lipid kinase activity and binding affinity for Talin. Our data reveal a novel function for PKD1 as a regulator of FA dynamics and by identifying PIP5Klγ as a novel PKD1 substrate provide mechanistic insight into this process.

  1. Influence of Ca2+ and Mg2+ on the turnover of the phosphomonoester group of phosphatidylinositol 4-phosphate in human erythrocyte membranes.

    PubMed Central

    Hegewald, H; Müller, E; Klinger, R; Wetzker, R; Frunder, H

    1987-01-01

    In isolated erythrocyte membranes, increasing the free Mg2+ concentration from 0.5 to 10 mM progressively activates the membrane-bound phosphatidylinositol (PtdIns) kinase and leads to the establishment of a new equilibrium with higher phosphatidylinositol 4-phosphate (PtdIns4P) and lower PtdIns concentrations. The steady-state turnover of the phosphomonoester group of PtdIns4P also increases at high Mg2+ concentrations, indicating a simultaneous activation of PtdIns4P phosphomonoesterase by Mg2+. Half-maximum inhibition of PtdIns kinase occurs at 10 microM free Ca2+ in the presence of physiological free Mg2+ concentrations. Increasing free Mg2+ concentrations overcome Ca2+ inhibition of PtdIns kinase. In the presence of Ca2+, calmodulin activates Ca2+-transporting ATPase 5-fold, but does not alter pool size and radiolabelling of PtdIns4P. In intact erythrocytes, adding EGTA or EGTA plus Mg2+ and the ionophore A23187 to the external medium does not exert significant effects on concentration and radiolabelling of polyphosphoinositides when compared with controls in the presence of 1.4 mM free Ca2+. PMID:2821996

  2. Analysis of the metabolic turnover of the individual phosphate groups of phosphatidylinositol 4-phosphate and phosphatidylinositol 4,5-bisphosphate. Validation of novel analytical techniques by using 32P-labelled lipids from erythrocytes.

    PubMed Central

    Hawkins, P T; Michell, R H; Kirk, C J

    1984-01-01

    We have developed methods that yield estimates of the 32P content of each of the individual phosphate groups of phosphatidylinositol 4-phosphate and phosphatidylinositol 4,5-bisphosphate, thus extending the information available from studies of the labelling of these lipids in intact cells or membrane preparations. The analyses are undertaken with the deacylated lipids. Assay of the 5-phosphate of phosphatidylinositol 4,5-bisphosphate is achieved by the use, under conditions of first-order kinetics, of a 5-phosphate-specific phosphomonoesterase present in isolated erythrocyte membranes [Downes, Mussat & Michell (1982) Biochem. J. 203, 169-177]. Assay of the 4-phosphate of phosphatidylinositol 4-phosphate and of the total monoester phosphate content (4-phosphate plus 5-phosphate) of phosphatidylinositol 4,5-bisphosphate employs alkaline phosphatase from bovine intestine. The radioactivity of the 1-phosphate is that remaining as organic phosphate after exhaustive alkaline phosphatase treatment. The methodology has been validated by using lipids from human erythrocytes: these contain no 32P in their 1-phosphate. These methods should be of substantial value in studies of the many cells that show rapid hormonal perturbations of phosphatidylinositol 4,5-bisphosphate metabolism. PMID:6326746

  3. Effector Vγ9Vδ2 T cells dominate the human fetal γδ T-cell repertoire

    PubMed Central

    Dimova, Tanya; Brouwer, Margreet; Gosselin, Françoise; Tassignon, Joël; Leo, Oberdan; Donner, Catherine; Marchant, Arnaud; Vermijlen, David

    2015-01-01

    γδ T cells are unconventional T cells recognizing antigens via their γδ T-cell receptor (TCR) in a way that is fundamentally different from conventional αβ T cells. γδ T cells usually are divided into subsets according the type of Vγ and/or Vδ chain they express in their TCR. T cells expressing the TCR containing the γ-chain variable region 9 and the δ-chain variable region 2 (Vγ9Vδ2 T cells) are the predominant γδ T-cell subset in human adult peripheral blood. The current thought is that this predominance is the result of the postnatal expansion of cells expressing particular complementary-determining region 3 (CDR3) in response to encounters with microbes, especially those generating phosphoantigens derived from the 2-C-methyl-d-erythritol 4-phosphate pathway of isoprenoid synthesis. However, here we show that, rather than requiring postnatal microbial exposure, Vγ9Vδ2 T cells are the predominant blood subset in the second-trimester fetus, whereas Vδ1+ and Vδ3+ γδ T cells are present only at low frequencies at this gestational time. Fetal blood Vγ9Vδ2 T cells are phosphoantigen responsive and display very limited diversity in the CDR3 of the Vγ9 chain gene, where a germline-encoded sequence accounts for >50% of all sequences, in association with a prototypic CDR3δ2. Furthermore, these fetal blood Vγ9Vδ2 T cells are functionally preprogrammed (e.g., IFN-γ and granzymes-A/K), with properties of rapidly activatable innatelike T cells. Thus, enrichment for phosphoantigen-responsive effector T cells has occurred within the fetus before postnatal microbial exposure. These various characteristics have been linked in the mouse to the action of selecting elements and would establish a much stronger parallel between human and murine γδ T cells than is usually articulated. PMID:25617367

  4. Plastoquinone and Ubiquinone in Plants: Biosynthesis, Physiological Function and Metabolic Engineering

    PubMed Central

    Liu, Miaomiao; Lu, Shanfa

    2016-01-01

    Plastoquinone (PQ) and ubiquinone (UQ) are two important prenylquinones, functioning as electron transporters in the electron transport chain of oxygenic photosynthesis and the aerobic respiratory chain, respectively, and play indispensable roles in plant growth and development through participating in the biosynthesis and metabolism of important chemical compounds, acting as antioxidants, being involved in plant response to stress, and regulating gene expression and cell signal transduction. UQ, particularly UQ10, has also been widely used in people’s life. It is effective in treating cardiovascular diseases, chronic gingivitis and periodontitis, and shows favorable impact on cancer treatment and human reproductive health. PQ and UQ are made up of an active benzoquinone ring attached to a polyisoprenoid side chain. Biosynthesis of PQ and UQ is very complicated with more than thirty five enzymes involved. Their synthetic pathways can be generally divided into two stages. The first stage leads to the biosynthesis of precursors of benzene quinone ring and prenyl side chain. The benzene quinone ring for UQ is synthesized from tyrosine or phenylalanine, whereas the ring for PQ is derived from tyrosine. The prenyl side chains of PQ and UQ are derived from glyceraldehyde 3-phosphate and pyruvate through the 2-C-methyl-D-erythritol 4-phosphate pathway and/or acetyl-CoA and acetoacetyl-CoA through the mevalonate pathway. The second stage includes the condensation of ring and side chain and subsequent modification. Homogentisate solanesyltransferase, 4-hydroxybenzoate polyprenyl diphosphate transferase and a series of benzene quinone ring modification enzymes are involved in this stage. PQ exists in plants, while UQ widely presents in plants, animals and microbes. Many enzymes and their encoding genes involved in PQ and UQ biosynthesis have been intensively studied recently. Metabolic engineering of UQ10 in plants, such as rice and tobacco, has also been tested. In this

  5. Assessment of Tumor Response to the Vascular Disrupting Agents 5,6-Dimethylxanthenone-4-Acetic Acid or Combretastatin-A4-Phosphate by Intrinsic Susceptibility Magnetic Resonance Imaging

    SciTech Connect

    McPhail, Lesley D. Griffiths, John R. D.Phil.; Robinson, Simon P.

    2007-11-15

    Purpose: To investigate the use of the transverse magnetic resonance imaging (MRI) relaxation rate R{sub 2}* (s{sup -1}) as a biomarker of tumor vascular response to monitor vascular disrupting agent (VDA) therapy. Methods and Materials: Multigradient echo MRI was used to quantify R{sub 2}* in rat GH3 prolactinomas. R{sub 2}* is a sensitive index of deoxyhemoglobin in the blood and can therefore be used to give an index of tissue oxygenation. Tumor R{sub 2}* was measured before and up to 35 min after treatment, and 24 h after treatment with either 350 mg/kg 5,6-dimethylxanthenone-4-acetic acid (DMXAA) or 100 mg/kg combretastatin-A4-phosphate (CA4P). After acquisition of the MRI data, functional tumor blood vessels remaining after VDA treatment were quantified using fluorescence microscopy of the perfusion marker Hoechst 33342. Results: DMXAA induced a transient, significant (p < 0.05) increase in tumor R{sub 2}* 7 min after treatment, whereas CA4P induced no significant changes in tumor R{sub 2}* over the first 35 min. Twenty-four hours after treatment, some DMXAA-treated tumors demonstrated a decrease in R{sub 2}*, but overall, reduction in R{sub 2}* was not significant for this cohort. Tumors treated with CA4P showed a significant (p < 0.05) reduction in R{sub 2}* 24 h after treatment. The degree of Hoechst 33342 uptake was associated with the degree of R{sub 2}* reduction at 24 h for both agents. Conclusions: The reduction in tumor R{sub 2}* or deoxyhemoglobin levels 24 h after VDA treatment was a result of reduced blood volume caused by prolonged vascular collapse. Our results suggest that DMXAA was less effective than CA4P in this rat tumor model.

  6. In Vivo Near-Infrared Spectroscopy and Magnetic Resonance Imaging Monitoring of Tumor Response to Combretastatin A-4-Phosphate Correlated With Therapeutic Outcome

    SciTech Connect

    Zhao Dawen; Chang Chenghui; Kim, Jae G.; Liu Hanli; Mason, Ralph P.

    2011-06-01

    Purpose: To develop a combination treatment consisting of combretastatin A-4-phosphate (CA4P) with radiation based on tumor oxygenation status. Methods and Materials: In vivo near-infrared spectroscopy (NIRS) and diffusion-weighted (DW) magnetic resonance imaging (MRI) were applied to noninvasively monitor changes in tumor blood oxygenation and necrosis induced by CA4P (30 mg/kg) in rat mammary 13762NF adenocarcinoma, and the evidence was used to optimize combinations of CA4P and radiation treatment (a single dose of 5 Gy). Results: NIRS showed decreasing concentrations of tumor vascular oxyhemoglobin and total hemoglobin during the first 2 h after CA4P treatment, indicating significant reductions in tumor blood oxygenation and perfusion levels (p < 0.001). Twenty-four hours later, in response to oxygen inhalation, significant recovery was observed in tumor vascular and tissue oxygenation according to NIRS and pimonidazole staining results, respectively (p < 0.05). DW MRI revealed significantly increased water diffusion in tumors measured by apparent diffusion coefficient at 24 h (p < 0.05), suggesting that CA4P-induced central necrosis. In concordance with the observed tumor oxygen dynamics, we found that treatment efficacy depended on the timing of the combined therapy. The most significant delay in tumor growth was seen in the group of tumors treated with radiation while the rats breathed oxygen 24 h after CA4P administration. Conclusions: Noninvasive evaluation of tumor oxygen dynamics allowed us to rationally enhance the response of syngeneic rat breast tumors to combined treatment of CA4P with radiation.

  7. Chloroplast localization of methylerythritol 4-phosphate pathway enzymes and regulation of mitochondrial genes in ispD and ispE albino mutants in Arabidopsis.

    PubMed

    Hsieh, Ming-Hsiun; Chang, Chiung-Yun; Hsu, Shih-Jui; Chen, Ju-Jiun

    2008-04-01

    Plant isoprenoids are derived from two independent pathways, the cytosolic mevalonate pathway and the plastid methylerythritol 4-phosphate (MEP) pathway. We used green fluorescent fusion protein assays to demonstrate that the Arabidopsis MEP pathway enzymes are localized to the chloroplast. We have also characterized three Arabidopsis albino mutants, ispD-1, ispD-2 and ispE-1, which have T-DNA insertions in the IspD and IspE genes of the MEP pathway. Levels of photosynthetic pigments are almost undetectable in these albino mutants. Instead of thylakoids, the ispD and ispE mutant chloroplasts are filled with large vesicles. Impairments in chloroplast development and functions may signal changes in the expression of nuclear, chloroplast and mitochondrial genes. We used northern blot analysis to examine the expression of photosynthetic and respiratory genes in the ispD and ispE albino mutants. Steady-state mRNA levels of nucleus- and chloroplast-encoded photosynthetic genes are significantly decreased in the albino mutants. In contrast, transcript levels of nuclear and mitochondrial genes encoding subunits of the mitochondrial electron transport chain are increased or not affected in these mutants. Genomic Southern blot analysis revealed that the DNA amounts of mitochondrial genes are not enhanced in the ispD and ispE albino mutants. These results support the notion that the functional state of chloroplasts may affect the expression of nuclear and mitochondrial genes. The up-regulation of mitochondrial genes in the albino mutants is not caused by changes of mitochondrial DNA copy number in Arabidopsis.

  8. Alternative security

    SciTech Connect

    Weston, B.H. )

    1990-01-01

    This book contains the following chapters: The Military and Alternative Security: New Missions for Stable Conventional Security; Technology and Alternative Security: A Cherished Myth Expires; Law and Alternative Security: Toward a Just World Peace; Politics and Alternative Security: Toward a More Democratic, Therefore More Peaceful, World; Economics and Alternative Security: Toward a Peacekeeping International Economy; Psychology and Alternative Security: Needs, Perceptions, and Misperceptions; Religion and Alternative Security: A Prophetic Vision; and Toward Post-Nuclear Global Security: An Overview.

  9. Synthesis of methylerythritol phosphate analogues and their evaluation as alternate substrates for IspDF and IspE from Agrobacterium tumefaciens.

    PubMed

    Krasutsky, Sergiy G; Urbansky, Marek; Davis, Chad E; Lherbet, Christian; Coates, Robert M; Poulter, C Dale

    2014-10-03

    The methylerythritol phosphate biosynthetic pathway, found in most Bacteria, some parasitic protists, and plant chloroplasts, converts D-glyceraldehyde phosphate and pyruvate to isopentenyl diphosphate (IPP) and dimethylallyl diphosphate (DMAPP), where it intersects with the mevalonate pathway found in some Bacteria, Archaea, and Eukarya, including the cytosol of plants. D-3-Methylerythritol-4-phosphate (MEP), the first pathway-specific intermediate in the pathway, is converted to IPP and DMAPP by the consecutive action of the IspD-H proteins. We synthesized five D-MEP analogues-D-erythritol-4-phosphate (EP), D-3-methylthrietol-4-phosphate (MTP), D-3-ethylerythritol-4-phosphate (EEP), D-1-amino-3-methylerythritol-4-phosphate (NMEP), and D-3-methylerythritol-4-thiolophosphate (MESP)-and studied their ability to function as alternative substrates for the reactions catalyzed by the IspDF fusion and IspE proteins from Agrobacterium tumefaciens, which covert MEP to the corresponding eight-membered cyclic diphosphate. All of the analogues, except MTP, and their products were substrates for the three consecutive enzymes.

  10. Synthesis of Methylerythritol Phosphate Analogues and Their Evaluation as Alternate Substrates for IspDF and IspE from Agrobacterium tumefaciens

    PubMed Central

    2015-01-01

    The methylerythritol phosphate biosynthetic pathway, found in most Bacteria, some parasitic protists, and plant chloroplasts, converts d-glyceraldehyde phosphate and pyruvate to isopentenyl diphosphate (IPP) and dimethylallyl diphosphate (DMAPP), where it intersects with the mevalonate pathway found in some Bacteria, Archaea, and Eukarya, including the cytosol of plants. d-3-Methylerythritol-4-phosphate (MEP), the first pathway-specific intermediate in the pathway, is converted to IPP and DMAPP by the consecutive action of the IspD-H proteins. We synthesized five d-MEP analogues—d-erythritol-4-phosphate (EP), d-3-methylthrietol-4-phosphate (MTP), d-3-ethylerythritol-4-phosphate (EEP), d-1-amino-3-methylerythritol-4-phosphate (NMEP), and d-3-methylerythritol-4-thiolophosphate (MESP)—and studied their ability to function as alternative substrates for the reactions catalyzed by the IspDF fusion and IspE proteins from Agrobacterium tumefaciens, which covert MEP to the corresponding eight-membered cyclic diphosphate. All of the analogues, except MTP, and their products were substrates for the three consecutive enzymes. PMID:25184438

  11. Alternative Fuels

    EPA Pesticide Factsheets

    Alternative fuels include gaseous fuels such as hydrogen, natural gas, and propane; alcohols such as ethanol, methanol, and butanol; vegetable and waste-derived oils; and electricity. Overview of alternative fuels is here.

  12. Alternative Therapies

    MedlinePlus

    ... Late Effects of Poliomyelitis for Physicians and Survivors © Alternative Therapies Alternative therapies, also called complementary, can support ... of motion, pain, and fatigue are often reported. Energy work includes acupuncture and acupressure, traditional Chinese medicine ...

  13. Influence of temperature and frequency on ionic conductivity of Li{sub 3}PO{sub 4}–Pb{sub 3}(PO{sub 4}){sub 2}–BiPO{sub 4} phosphate glasses

    SciTech Connect

    El Moudane, M.; El Maniani, M.; Sabbar, A.; Ghanimi, A.; Tabyaoui, M.; Bellaouchou, A.; Guenbour, A.

    2015-12-15

    Highlights: • Results of ionic conductivities of Li{sub 3}PO{sub 4}–Pb{sub 3}(PO{sub 4}){sub 2}–BiPO{sub 4} phosphate glasses. • Determination of glass transition temperature using DSC method. • Study of temperature and frequency on ionic conductivity of Li{sub 3}PO{sub 4}–Pb{sub 3}(PO{sub 4}){sub 2}–BiPO{sub 4} phosphate glasses. - Abstract: Lithium–Lead–Bismuth phosphates glasses having, a composition 30Li{sub 3}PO{sub 4}–(70 − x)Pb{sub 3}(PO{sub 4}){sub 2}–xBiPO{sub 4} (45 ≤ x ≤ 60 mol%) were prepared by using the melt quenching method 1000 °C. The thermal stability of theses glasses increases with the substitution of Bi{sub 2}O{sub 3} with PbO. The ionic conductivity of all compositions have been measured over a wide temperature (200–500 °C) and frequency range (1–106 Hz). The ionic conductivity data below and above T{sub g} follows Arrhenius and Vogel–Tamman–Fulcher (VTF) relationship, respectively. The activation energies are estimated and discussed. The dependence in frequency of AC conductivity is found to obey Jonscher’s relation.

  14. Alternative fuels

    SciTech Connect

    Not Available

    1991-07-01

    This paper presents the preliminary results of a review, of the experiences of Brazil, Canada, and New Zealand, which have implemented programs to encourage the use of alternative motor fuels. It will also discuss the results of a separate completed review of the Department of Energy's (DOE) progress in implementing the Alternative Motor Fuels Act of 1988. The act calls for, among other things, the federal government to use alternative-fueled vehicles in its fleet. The Persian Gulf War, environmental concerns, and the administration's National Energy Strategy have greatly heightened interest in the use of alternative fuels in this country.

  15. Pleasant Alternatives.

    ERIC Educational Resources Information Center

    Unks, Gerald

    1981-01-01

    The author feels that the current wave of political conservatism may prove beneficial to education if the national mood of decentralization and decontrol leads to a resurgence of community involvement and locally-developed alternatives. He cites several examples of successful urban alternative schools. (SJL)

  16. Alternative Schools.

    ERIC Educational Resources Information Center

    Annett, Larry D.

    A model is presented for the categorizing of alternative schools, then the nature of the free school, which represents the essence of the alternative school movement, is examined. Strengths and weaknesses of court, legislative, and administrative approaches to resolve governance issues are set forth. This is followed by an analysis of three…

  17. Alternative Assessment.

    ERIC Educational Resources Information Center

    Stefonek, Tom; And Others

    1991-01-01

    This special double issue focuses on the issue of alternative assessment and its place in educational reform. "Alternative Assessment: A National Perspective" (T. Stefonek) emphasizes that the fundamental purposes of new assessment methods are grounded in educational goals, meaningful outcomes, and curricular and instructional programs…

  18. Alternative Schools.

    ERIC Educational Resources Information Center

    Pritchett, Stanley; Kimsey, Steve

    2002-01-01

    Describes the design of the DeKalb Alternative School in Atlanta, Georgia, located in a renovated shopping center. Purchasing commercial land and renovating the existing building saved the school system time and money. (EV)

  19. The direct interaction between ASH2, a Drosophila trithorax group protein, and SKTL, a nuclear phosphatidylinositol 4-phosphate 5-kinase, implies a role for phosphatidylinositol 4,5-bisphosphate in maintaining transcriptionally active chromatin.

    PubMed Central

    Cheng, Mimi K; Shearn, Allen

    2004-01-01

    The products of trithorax group (trxG) genes maintain active transcription of many important developmental regulatory genes, including homeotic genes. Several trxG proteins have been shown to act in multimeric protein complexes that modify chromatin structure. ASH2, the product of the Drosophila trxG gene absent, small, or homeotic discs 2 (ash2) is a component of a 500-kD complex. In this article, we provide biochemical evidence that ASH2 binds directly to Skittles (SKTL), a predicted phosphatidylinositol 4-phosphate 5-kinase, and genetic evidence that the association of these proteins is functionally significant. We also show that histone H1 hyperphosphorylation is dramatically increased in both ash2 and sktl mutant polytene chromosomes. These results suggest that ASH2 maintains active transcription by binding a producer of nuclear phosphoinositides and downregulating histone H1 hyperphosphorylation. PMID:15280236

  20. Magnetostrictive Alternator

    NASA Technical Reports Server (NTRS)

    Dyson, Rodger; Bruder, Geoffrey

    2013-01-01

    This innovation replaces the linear alternator presently used in Stirling engines with a continuous-gradient, impedance-matched, oscillating magnetostrictive transducer that eliminates all moving parts via compression, maintains high efficiency, costs less to manufacture, reduces mass, and eliminates the need for a bearing system. The key components of this new technology are the use of stacked magnetostrictive materials, such as Terfenol-D, under a biased magnetic and stress-induced compression, continuous-gradient impedance-matching material, coils, force-focusing metallic structure, and supports. The acoustic energy from the engine travels through an impedancematching layer that is physically connected to the magnetostrictive mass. Compression bolts keep the structure under compressive strain, allowing for the micron-scale compression of the magnetostrictive material and eliminating the need for bearings. The relatively large millimeter displacement of the pressure side of the impedance-matching material is reduced to micron motion, and undergoes stress amplification at the magnetostrictive interface. The alternating compression and expansion of the magnetostrictive material creates an alternating magnetic field that then induces an electric current in a coil that is wound around the stack. This produces electrical power from the acoustic pressure wave and, if the resonant frequency is tuned to match the engine, can replace the linear alternator that is commonly used.

  1. ALTERNATIVE OXIDANTS

    EPA Science Inventory

    This chapter reports on the efforts of the USEPA to study chloramines, chlorine dioxide and ozone as alternative oxidants/disinfectants to chlorine for the control of disinfection by-rpdocuts (DBPs) in drinking water. It examines the control of DBPs like trihalomethanes and haloa...

  2. Alternative Thinking.

    ERIC Educational Resources Information Center

    Herman, Dan

    1999-01-01

    Explains how advances in diesel and alternative fuels has caused schools to reconsider their use for their bus fleets. Reductions in air pollution emissions, cost-savings developments, and the economies experienced from less downtime and maintenance requirements are explored. (GR)

  3. Alternative fuels

    NASA Technical Reports Server (NTRS)

    Grobman, J. S.; Butze, H. F.; Friedman, R.; Antoine, A. C.; Reynolds, T. W.

    1977-01-01

    Potential problems related to the use of alternative aviation turbine fuels are discussed and both ongoing and required research into these fuels is described. This discussion is limited to aviation turbine fuels composed of liquid hydrocarbons. The advantages and disadvantages of the various solutions to the problems are summarized. The first solution is to continue to develop the necessary technology at the refinery to produce specification jet fuels regardless of the crude source. The second solution is to minimize energy consumption at the refinery and keep fuel costs down by relaxing specifications.

  4. A High and Phosphatidylinositol-4-phosphate (PI4P)-dependent ATPase Activity for the Drs2p/Cdc50p Flippase after Removal of its N- and C-terminal Extensions.

    PubMed

    Azouaoui, Hassina; Montigny, Cédric; Dieudonné, Thibaud; Champeil, Philippe; Jacquot, Aurore; Vázquez-Ibar, José Luis; Le Maréchal, Pierre; Ulstrup, Jakob; Ash, Miriam-Rose; Lyons, Joseph A; Nissen, Poul; Lenoir, Guillaume

    2017-03-16

    P4-ATPases, also known as phospholipid flippases, are responsible for creating and maintaining transbilayer lipid asymmetry in eukaryotic cell membranes. Here, we use limited proteolysis to investigate the role of the N- and C-termini in ATP hydrolysis and auto-inhibition of the yeast flippase Drs2p/Cdc50p. We show that limited proteolysis of the detergent-solubilized and purified yeast flippase may result in more than one order of magnitude increase of its ATPase activity, which remains dependent on phosphatidylinositol-4-phosphate (PI4P), a regulator of this lipid flippase, and specific to a phosphatidylserine substrate. Using thrombin as the protease, Cdc50p remains intact and in complex with Drs2p, which is cleaved at two positions, namely after R104 and after R1290, resulting in a homogenous sample lacking 104 and 65 residues from its N- and C-termini, respectively. Removal of the 1291-1302 region of the C-terminal extension is critical for relieving the auto-inhibition of full-length Drs2p, while the 1-104 N-terminal residues have an additional but more modest significance for activity. The present results therefore reveal that trimming off appropriate regions of the terminal extensions of Drs2p can greatly increase its ATPase activity in the presence of PI4P, and demonstrate that relief of such auto-inhibition remains compatible with subsequent regulation by PI4P. These experiments suggest that activation of the Drs2p/Cdc50p flippase follows a multi-step mechanism, with preliminary release of a number of constraints, possibly through the binding of regulatory proteins in the trans-Golgi network, followed by full activation by PI4P.

  5. Alternative Splice in Alternative Lice.

    PubMed

    Tovar-Corona, Jaime M; Castillo-Morales, Atahualpa; Chen, Lu; Olds, Brett P; Clark, John M; Reynolds, Stuart E; Pittendrigh, Barry R; Feil, Edward J; Urrutia, Araxi O

    2015-10-01

    Genomic and transcriptomics analyses have revealed human head and body lice to be almost genetically identical; although con-specific, they nevertheless occupy distinct ecological niches and have differing feeding patterns. Most importantly, while head lice are not known to be vector competent, body lice can transmit three serious bacterial diseases; epidemictyphus, trench fever, and relapsing fever. In order to gain insights into the molecular bases for these differences, we analyzed alternative splicing (AS) using next-generation sequencing data for one strain of head lice and one strain of body lice. We identified a total of 3,598 AS events which were head or body lice specific. Exon skipping AS events were overrepresented among both head and body lice, whereas intron retention events were underrepresented in both. However, both the enrichment of exon skipping and the underrepresentation of intron retention are significantly stronger in body lice compared with head lice. Genes containing body louse-specific AS events were found to be significantly enriched for functions associated with development of the nervous system, salivary gland, trachea, and ovarian follicle cells, as well as regulation of transcription. In contrast, no functional categories were overrepresented among genes with head louse-specific AS events. Together, our results constitute the first evidence for transcript pool differences in head and body lice, providing insights into molecular adaptations that enabled human lice to adapt to clothing, and representing a powerful illustration of the pivotal role AS can play in functional adaptation.

  6. Alternative Splice in Alternative Lice

    PubMed Central

    Tovar-Corona, Jaime M.; Castillo-Morales, Atahualpa; Chen, Lu; Olds, Brett P.; Clark, John M.; Reynolds, Stuart E.; Pittendrigh, Barry R.; Feil, Edward J.; Urrutia, Araxi O.

    2015-01-01

    Genomic and transcriptomics analyses have revealed human head and body lice to be almost genetically identical; although con-specific, they nevertheless occupy distinct ecological niches and have differing feeding patterns. Most importantly, while head lice are not known to be vector competent, body lice can transmit three serious bacterial diseases; epidemictyphus, trench fever, and relapsing fever. In order to gain insights into the molecular bases for these differences, we analyzed alternative splicing (AS) using next-generation sequencing data for one strain of head lice and one strain of body lice. We identified a total of 3,598 AS events which were head or body lice specific. Exon skipping AS events were overrepresented among both head and body lice, whereas intron retention events were underrepresented in both. However, both the enrichment of exon skipping and the underrepresentation of intron retention are significantly stronger in body lice compared with head lice. Genes containing body louse-specific AS events were found to be significantly enriched for functions associated with development of the nervous system, salivary gland, trachea, and ovarian follicle cells, as well as regulation of transcription. In contrast, no functional categories were overrepresented among genes with head louse-specific AS events. Together, our results constitute the first evidence for transcript pool differences in head and body lice, providing insights into molecular adaptations that enabled human lice to adapt to clothing, and representing a powerful illustration of the pivotal role AS can play in functional adaptation. PMID:26169943

  7. Evaluation of coriander spice as a functional food by using in vitro bioassays.

    PubMed

    Zhang, Chuan-Rui; Dissanayake, Amila A; Kevseroğlu, Kudret; Nair, Muraleedharan G

    2015-01-15

    Coriander leaves and seeds are widely used as a condiment and spice. The use of roasted coriander seeds in food and beverage is very common. In this study, we investigated raw and roasted coriander seeds for their functional food quality using antioxidant, anti-inflammatory and human tumour cell proliferation inhibitory assays. The hexane and methanolic extracts of raw and roasted coriander seeds showed identical chromatographic and bioassay profiles. Chromatographic purification of the roasted seed extracts afforded tripetroselinin as the predominant component. Other isolates were petroselinic acid, 1,3-dipetroselinin, 2-C-methyl-d-erythritol, 2-C-methyl-d-erythritol 4-O-β-d-glucopyranoside and linalool. Hexane and methanolic extracts of both raw and roasted seeds and pure isolates from them showed comparable antioxidant and anti-inflammatory activities to the positive controls used in the assays, and inhibited the growth of human tumour cells AGS (gastric carcinoma), DU-145 and LNCaP (prostate carcinoma), HCT-116 (colon carcinoma), MCF-7 (breast carcinoma) and NCI-H460 (lung carcinoma) by 4-34%, respectively.

  8. Looking for an Alternative.

    ERIC Educational Resources Information Center

    Kennedy, Jack

    1999-01-01

    Argues that high school newspapers might do well to create stronger ties with alternative weeklies. Discusses issues of niche marketing, alternative content, and alternative presentation. Notes that high school papers could learn a lot from alternative newspapers. (SR)

  9. A High-Yield Co-Expression System for the Purification of an Intact Drs2p-Cdc50p Lipid Flippase Complex, Critically Dependent on and Stabilized by Phosphatidylinositol-4-Phosphate

    PubMed Central

    Azouaoui, Hassina; Montigny, Cédric; Ash, Miriam-Rose; Fijalkowski, Frank; Jacquot, Aurore; Grønberg, Christina; López-Marqués, Rosa L.; Palmgren, Michael G.; Garrigos, Manuel; le Maire, Marc; Decottignies, Paulette; Gourdon, Pontus; Nissen, Poul; Champeil, Philippe; Lenoir, Guillaume

    2014-01-01

    P-type ATPases from the P4 subfamily (P4-ATPases) are energy-dependent transporters, which are thought to establish lipid asymmetry in eukaryotic cell membranes. Together with their Cdc50 accessory subunits, P4-ATPases couple ATP hydrolysis to lipid transport from the exoplasmic to the cytoplasmic leaflet of plasma membranes, late Golgi membranes, and endosomes. To gain insights into the structure and function of these important membrane pumps, robust protocols for expression and purification are required. In this report, we present a procedure for high-yield co-expression of a yeast flippase, the Drs2p-Cdc50p complex. After recovery of yeast membranes expressing both proteins, efficient purification was achieved in a single step by affinity chromatography on streptavidin beads, yielding ∼1–2 mg purified Drs2p-Cdc50p complex per liter of culture. Importantly, the procedure enabled us to recover a fraction that mainly contained a 1∶1 complex, which was assessed by size-exclusion chromatography and mass spectrometry. The functional properties of the purified complex were examined, including the dependence of its catalytic cycle on specific lipids. The dephosphorylation rate was stimulated in the simultaneous presence of the transported substrate, phosphatidylserine (PS), and the regulatory lipid phosphatidylinositol-4-phosphate (PI4P), a phosphoinositide that plays critical roles in membrane trafficking events from the trans-Golgi network (TGN). Likewise, overall ATP hydrolysis by the complex was critically dependent on the simultaneous presence of PI4P and PS. We also identified a prominent role for PI4P in stabilization of the Drs2p-Cdc50p complex towards temperature- or C12E8-induced irreversible inactivation. These results indicate that the Drs2p-Cdc50p complex remains functional after affinity purification and that PI4P as a cofactor tightly controls its stability and catalytic activity. This work offers appealing perspectives for detailed structural and

  10. Regulation of resin acid synthesis in Pinus densiflora by differential transcription of genes encoding multiple 1-deoxy-D-xylulose 5-phosphate synthase and 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate reductase genes.

    PubMed

    Kim, Yeon-Bok; Kim, Sang-Min; Kang, Min-Kyoung; Kuzuyama, Tomohisa; Lee, Jong Kyu; Park, Seung-Chan; Shin, Sang-Chul; Kim, Soo-Un

    2009-05-01

    Pinus densiflora Siebold et Zucc. is the major green canopy species in the mountainous area of Korea. To assess the response of resin acid biosynthetic genes to mechanical and chemical stimuli, we cloned cDNAs of genes encoding enzymes involved in the 2-C-methyl-d-erythritol 4-phosphate (MEP) pathway (1-deoxy-d-xylulose 5-phosphate synthase (PdDXS), 1-deoxy-d-xylulose 5-phosphate reductoisomerase (PdDXR) and 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate reductase (PdHDR)) by the rapid amplification of cDNA ends (RACE) technique. In addition, we cloned the gene encoding abietadiene synthase (PdABS) as a marker for the site of pine resin biosynthesis. PdHDR and PdDXS occurred as two gene families. In the phylogenetic trees, PdDXSs, PdDXR and PdHDRs each formed a separate clade from their respective angiosperm homologs. PdDXS2, PdHDR2 and PdDXR were most actively transcribed in stem wood, whereas PdABS was specifically transcribed. The abundance of PdDXS2 transcripts in wood in the resting state was generally 50-fold higher than the abundance of PdDXS1 transcripts, and PdHDR2 transcripts were more abundant by an order of magnitude in wood than in other tissues, with the ratio of PdHDR2 to PdHDR1 transcripts in wood being about 1. Application of 1 mM methyl jasmonate (MeJA) selectively enhanced the transcript levels of PdDXS2 and PdHDR2 in wood. The ratios of PdDXS2 to PdDXS1 and PdHDR2 to PdHDR1 reached 900 and 20, respectively, on the second day after MeJA treatment, whereas the transcript level of PdABS increased twofold by 3 days after MeJA treatment. Wounding of the stem differentially enhanced the transcript ratios of PdDXS2 to PdDXS1 and PdHDR2 to PdHDR1 to 300 and 70, respectively. The increase in the transcript levels of the MEP pathway genes in response to wounding was accompanied by two orders of magnitude increase in PdABS transcripts. These observations indicated that resin acid biosynthesis activity, represented by PdABS transcription, was correlated

  11. Approaches to Alternative Assessment.

    ERIC Educational Resources Information Center

    Hamayan, Else V.

    1995-01-01

    Examines the major characteristics of nontraditional or alternative assessment in language learning, the uses of alternative assessment procedures, and different types of alternative assessment. An annotated bibliography discusses eight important works in the field. (75 references) (MDM)

  12. All About Alternatives

    ERIC Educational Resources Information Center

    Barr, Robert D.; And Others

    1972-01-01

    A primer on alternative schools. Described are existing programs in different areas, philosophy of the alternative schools, funding, student behavior, community relations, accountability, State regulations, management, and the environment of the alternative school. A list of sources of additional information on alternative schools is included.…

  13. Alternative and Integrative Medicine

    MedlinePlus

    ... Alternative & Integrative Medicine Clinical Trials GBM AGILE TTFields – Optune™ Brain Tumor Treatment Locations Treatment Side Effects & their ... Alternative & Integrative Medicine Clinical Trials GBM AGILE TTFields – Optune™ Brain Tumor Treatment Locations Treatment Side Effects & their ...

  14. Alternative Refractive Surgery Procedures

    MedlinePlus

    ... LASIK Alternative Refractive Surgery Procedures Laser Surgery Recovery Alternative Refractive Surgery Procedures Dec. 12, 2015 Today's refractive ... that releases controlled amounts of radio frequency (RF) energy, instead of a laser, to apply heat to ...

  15. Shoreside Alternative Energy Evaluation

    DTIC Science & Technology

    2002-09-01

    in November 2000 titled, Shoreside Alternative Energy Evaluation. This study of alternative energies focused on usage of natural gas, and included...energy sources such as costs, benefits, and logistic availability. This study of alternative energies focused on usage of natural gas and included...resources in this area. Recognizing Air Station Cape Cod as a leader in utilizing alternative energies , the Research and Development Center established

  16. Alternatives for Education Manual.

    ERIC Educational Resources Information Center

    Alternatives for Education, San Pedro, CA.

    A directory of alternative schools and a list of books and reprints about alternative education are presented. The alternative schools listed are almost all on the West Coast and include both day and boarding schools at the primary and secondary level. The name and address of each school is given along with supplementary material about its…

  17. Chicano Alternative Education.

    ERIC Educational Resources Information Center

    Galicia, H. Homero; Almaguer, Clementina

    Alternative schooling is challenging some basic notions of curriculum, operation, and structure of traditional schools; it is not challenging the basic concept of schooling. Chicano alternative education, an elusive concept, lacks a precise definition. Chicano alternative schools reflect a vast diversity in structure, focus, and goals. The Chicano…

  18. Assessment "Honest Alternatives".

    ERIC Educational Resources Information Center

    Mandel, Susan Glazer

    1995-01-01

    Addresses the challenge of finding or creating alternatives to tests and traditional grading systems. Reflects on and describes the experience of creating an assessment tool and cautions against choosing alternatives that merely camouflage the grades. Encourages educators to find authentic alternatives to describe children's growth. (BAC)

  19. Alternative Certification Isn't Alternative

    ERIC Educational Resources Information Center

    Walsh, Kate; Jacobs, Sandi

    2007-01-01

    While nearly all states now have something on their books labeled "alternate route to certification," these programs defy standard definition due to their enormous variability. States differ in the types of candidates allowed to apply (e.g., career changers or recent college graduates) and in the academic backgrounds these individuals must…

  20. On alternating quantum walks

    NASA Astrophysics Data System (ADS)

    Rousseva, Jenia; Kovchegov, Yevgeniy

    2017-03-01

    We study an inhomogeneous quantum walk on a line that evolves according to alternating coins, each a rotation matrix. For the quantum walk with the coin alternating between clockwise and counterclockwise rotations by the same angle, we derive a closed form solution for the propagation of probabilities, and provide its asymptotic approximation via the method of stationary phase. Finally, we observe that for a x03c0;/4 angle, this alternating rotation walk will replicate the renown Hadamard walk.

  1. Alternatives to Certain Phthalates Partnership

    EPA Pesticide Factsheets

    The alternatives assessment partnership project on alternatives to certain phthalates seeks to eplore the human health and environmental profiles of eight action plan phthalates and functional alternatives

  2. Alternator insulation evaluation tests

    NASA Technical Reports Server (NTRS)

    Penn, W. B.; Schaefer, R. F.; Balke, R. L.

    1972-01-01

    Tests were conducted to predict the remaining electrical insulation life of a 60 KW homopolar inductor alternator following completion of NASA turbo-alternator endurance tests for SNAP-8 space electrical power systems application. The insulation quality was established for two alternators following completion of these tests. A step-temperature aging test procedure was developed for insulation life prediction and applied to one of the two alternators. Armature winding insulation life of over 80,000 hours for an average winding temperature of 248 degrees C was predicted using the developed procedure.

  3. Alternative Automobile Engines

    ERIC Educational Resources Information Center

    Wilson, David Gordon

    1978-01-01

    Requirements for cleaner and more efficient engines have stimulated a search for alternatives to the conventional spark-ignition engine. So far, the defects of the alternative engines are clearer than the virtues. The following engines are compared: spark ignition, diesel, vapor-cycle, Stirling, and gas turbine. (Author/MA)

  4. System Alternatives Project

    ERIC Educational Resources Information Center

    Petrait, James A.

    1977-01-01

    The Systems Alternatives Project is an attempt to develop open classroom alternatives within a modular scheduling system. Biology students are given both action and test objectives that emphasize individualization. Structure of the project is detailed and an attempt to analyze the project evaluation data statistically is included. (MA)

  5. Alternative Schools, Mainstream Education

    ERIC Educational Resources Information Center

    McKee, Jan; Conner, Evguenia

    2007-01-01

    Alternative education has its own history. Having emerged in the sixties as a response to the social crisis, its goal was primarily to fight increasing bureaucracy and the depersonalization of public education by giving students more freedom and minimal adult supervision. In the eighties, the understanding of "alternative education" narrowed to…

  6. Alternative Work Programs

    ERIC Educational Resources Information Center

    Kuehn, Kerri L.

    2004-01-01

    Employers are feeling the strain of needing to offer alternative work arrangements to retain and recruit employees. Due to a change in demographics, dual-career couples and increased technology; people are demanding a transformation in the workplace environment. Two alternatives, which are being offered by employers, are flextime and…

  7. Alternative Fuels Data Center

    SciTech Connect

    2013-06-01

    Fact sheet describes the Alternative Fuels Data Center, which provides information, data, and tools to help fleets and other transportation decision makers find ways to reduce petroleum consumption through the use of alternative and renewable fuels, advanced vehicles, and other fuel-saving measures.

  8. Alternatives to blood transfusion.

    PubMed

    Spahn, Donat R; Goodnough, Lawrence T

    2013-05-25

    The use of alternatives to allogeneic blood continues to rest on the principles that blood transfusions have inherent risks, associated costs, and affect the blood inventory available for health-care delivery. Increasing evidence exists of a fall in the use of blood because of associated costs and adverse outcomes, and suggests that the challenge for the use of alternatives to blood components will similarly be driven by costs and patient outcomes. Additionally, the risk-benefit profiles of alternatives to blood transfusion such as autologous blood procurement, erythropoiesis-stimulating agents, and haemostatic agents are under investigation. Nevertheless, the inherent risks of blood, along with the continued rise in blood costs are likely to favour the continued development and use of alternatives to blood transfusion. We summarise the current roles of alternatives to blood in the management of medical and surgical anaemias.

  9. Alternative fuel transit buses

    SciTech Connect

    Motta, R.; Norton, P.; Kelly, K.

    1996-10-01

    The National Renewable Energy Laboratory (NREL) is a U.S. Department of Energy (DOE) national laboratory; this project was funded by DOE. One of NREL`s missions is to objectively evaluate the performance, emissions, and operating costs of alternative fuel vehicles so fleet managers can make informed decisions when purchasing them. Alternative fuels have made greater inroads into the transit bus market than into any other. Each year, the American Public Transit Association (APTA) surveys its members on their inventory and buying plans. The latest APTA data show that about 4% of the 50,000 transit buses in its survey run on an alternative fuel. Furthermore, 1 in 5 of the new transit buses that members have on order are alternative fuel buses. This program was designed to comprehensively and objectively evaluate the alternative fuels in use in the industry.

  10. Alternate Fuels Combustion Research

    DTIC Science & Technology

    1983-10-01

    AFWAL-TR-83-2057 AD A13 8 5 7 5 ALTERNATE FUELS COMBUSTION RESEARCH PHASE RI ’~*~~4 & IWITEY CMAAA * ’s~t:Uwz, ONTARIO October 1983 I•oerls Report...83-2057 P_______________ C TITLE (mod ,,--tt-) 5. TYPE OF REPORT A PERIOD COVERED Alternate Fuels ioahusticn Research Interim Report for Period Phase...I$. KEY WORDS (Continue on reverse sirte it necessear and identify by block number) FUELS ALTERNATE FUELS GAS TURBINE COMBUSTION EXHAUST EMISSIONS 0

  11. Alternate Fuels Combustion Research

    DTIC Science & Technology

    1984-07-01

    AFWAL-TR-84-2042 ESL-TR-84-29 ALTERNATE FUELS COMBUSTION RESEARCH 0) PRATT & WHITNEY CANADA MISSISSAUGA, ONTARIO CANADA In JULY 1984 Final Report for...in small engincs. -291 REFERENCES 1. Gratton, M., Sampath, P., " Alternate Fuels Combustion Research Phase If", Pratt & Whitney Canada , AFWAL-TR-83-2057...for Period May 80 Sep e ALTERNATE FUELS COMBUSTION RESEARCHMa80-Sp3 4. PERFORMING ORIJ. REPORT NUMBER 7. AUTNOR(s) 4. 60ONTRA-CT-WI GANUMNER(s) *M

  12. Marking: A Critical Alternative.

    ERIC Educational Resources Information Center

    Hull, Charles

    1984-01-01

    Having pupils critique their own work is an alternative to marking that is worthy of consideration. Pupil critique fosters in students a willingness to take responsibility for the quality of their work products. (RM)

  13. Alternative fuel information sources

    SciTech Connect

    Not Available

    1994-06-01

    This short document contains a list of more than 200 US sources of information (Name, address, phone number, and sometimes contact) related to the use of alternative fuels in automobiles and trucks. Electric-powered cars are also included.

  14. An Alternative to Tradition

    ERIC Educational Resources Information Center

    Dunathan, Arni; Guenther, John

    1970-01-01

    Two faculty members from the University of Missouri propose film making as an alternative to writing as a means of self expression for today's students and offer suggestions for preparing and operating a film production program. (LS)

  15. Complementary and Alternative Medicine

    MedlinePlus

    ... use practices like acupuncture in medicine. But until recently, most Western hospitals didn't provide any alternative ... medicine is often used instead of conventional medical techniques. Complementary medicine is used in addition to conventional ...

  16. Alternative disinfectant water treatments

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alternative disinfestant water treatments are disinfestants not as commonly used by the horticultural industry. Chlorine products that produce hypochlorous acid are the main disinfestants used for treating irrigation water. Chlorine dioxide will be the primary disinfestant discussed as an alternativ...

  17. Consumer Health: Alternative Therapy

    MedlinePlus

    ... classified by the National Center for Complementary and Alternative Medicine (NCCAM): Whole medical systems Mind-body medicine Biologically based practices Manipulative and body-based practices Energy medicine Keep in mind that the distinctions between ...

  18. Seal design alternatives study

    SciTech Connect

    Van Sambeek, L.L.

    1993-06-01

    This report presents the results from a study of various sealing alternatives for the WIPP sealing system. Overall, the sealing system has the purpose of reducing to the extent possible the potential for fluids (either gas or liquid) from entering or leaving the repository. The sealing system is divided into three subsystems: drift and panel seals within the repository horizon, shaft seals in each of the four shafts, and borehole seals. Alternatives to the baseline configuration for the WIPP seal system design included evaluating different geometries and schedules for seal component installations and the use of different materials for seal components. Order-of-magnitude costs for the various alternatives were prepared as part of the study. Firm recommendations are not presented, but the advantages and disadvantages of the alternatives are discussed. Technical information deficiencies are identified and studies are outlined which can provide required information.

  19. GLOBAL ALTERNATIVE FUTURE SCENARIOS

    EPA Science Inventory

    One way to examine possible future outcomes for environmental protection is through the development and analysis of alternative future scenarios. This type of assessment postulates two or more different paths that social and environmental development might take, using correspond...

  20. Alternative Fuels Infrastructure Development

    SciTech Connect

    Bloyd, Cary N.

    2010-06-30

    This summary reviews the status of alternate transportation fuels development and utilization in Thailand. An understanding of the issues and experiences associated with the introduction of alternative fuels in other countries can help the US in anticipation potential problems as it introduces new automotive fuels. Thailand is of particular interest since it introduced E20 to its commercial market in 2007 and the US is now considering introducing E20 into the US market.

  1. Alternative Policy Instruments

    DTIC Science & Technology

    1987-11-01

    CpRE CENTER FOR POLICY RESEARCH IN EDUCATION Alternative Policy o Instruments I Lorraine M. McDonnell Richard F. Elmore November 1987 DTICELECTE...03 Alternative Policy Instruments Lorraine M. McDonnell The RAND Corporation Richard F. Elmore Michigan State University November 1987 THRAND...range of policy instruments available or on the political and organizational conditions needed for each to work as intended. Policy decisions would

  2. [The role of 2-C-methylerythritol-2,4-cyclopyrophosphate in the resuscitation of the "nonculturable" forms of Mycobacterium smegmatis].

    PubMed

    Goncharenko, A V; Ershov, Iu V; Salina, E G; Wiesner, J; Vostroknutova, G N; Sandanov, A A; Kapel'iants, A S; Ostrovskiĭ, D N

    2007-01-01

    2-C-Methyl-D-erythritol-2,4-cyclopyrophosphate (MEC), an intermediate of the biosynthesis of isoprenoid compounds in bacteria, was found to be capable of exerting a resuscitating effect on resting Mycobacterium smegmatis cells. The introduction of an additional copy of the ispE gene encoding cytidyl-methylerythritol kinase, an enzyme involved in MEC synthesis in M. smegmatis, resulted in the emergence of a capacity for spontaneous reactivation of "nonculturable" M. smegmatis cells, which is not characteristic of the wild-type cells of this species. The involvement of MEC in the transition from the "nonculturable" state to the state of active growth is indicative of a previously unknown function of MEC, assumed to consist in regulation of the bacterial genome activity.

  3. Alternate policies for alternate energy sources

    SciTech Connect

    Hall, F.F.

    1985-09-01

    Some ''alternates within alternates'' are studied and possible improvement of our energy policies are explored. The viability of a hydrogen fuel economy is reviewed. Methanol, ethanol or ammonia versus hydrogen is one area of interest. Others include liquid hydrogen versus jet fuels, the use of geothermal, solar, wind or water energy for production of hydrogen gas versus development of deep earth supplies of natural gas is another. Energy enhancement as opposed to energy conservation is investigated with regard to polar climate and what might be done to improve natural energy balances, particularly in the northern hemisphere. Pumping Arctic Ocean water out into the Pacific Ocean via the Bering Strait would be an energy debit as opposed to energy gains such as biomass conversion of future plant growth throughout the Siberian and Canadian tundra regions and presently very arid desert regions, improved access to northern region fuel, metal ore and mineral resources, year-round shipping and fishing fleet operations in the Arctic Ocean and development of the tremendous Greenland hydro-electric power potential.

  4. Alternative drugs of abuse.

    PubMed

    Sutter, M E; Chenoweth, J; Albertson, T E

    2014-02-01

    The incidence of drug abuse with alternative agents is increasing. The term "alternative drugs of abuse" is a catch-all term for abused chemicals that do not fit into one of the classic categories of drugs of abuse. The most common age group abusing these agents range from 17 to 25 years old and are often associated with group settings. Due to their diverse pharmacological nature, legislative efforts to classify these chemicals as a schedule I drug have lagged behind the development of new alternative agents. The potential reason for abuse of these agents is their hallucinogenic, dissociative, stimulant, anti-muscarinic, or sedative properties. Some of these drugs are easily obtainable such as Datura stramonium (Jimson Weed) or Lophophora williamsii (Peyote) because they are natural plants indigenous to certain regions. The diverse pharmacology and clinical effects of these agents are so broad that they do not produce a universal constellation of signs and symptoms. Detailed physical exams are essential for identifying clues leading one to suspect an alternative drug of abuse. Testing for the presence of these agents is often limited, and even when available, the results do not return in a timely fashion. Intoxications from these agents pose unique challenges for health care providers. Physician knowledge of the physiological effects of these alternative agents and the local patterns of drug of abuse are important for the accurate diagnosis and optimal care of poisoned patients. This review summarizes the current knowledge of alternative drugs of abuse and highlights their clinical presentations.

  5. Effects of Feeding Spodoptera littoralis on Lima Bean Leaves: IV. Diurnal and Nocturnal Damage Differentially Initiate Plant Volatile Emission1[W][OA

    PubMed Central

    Arimura, Gen-ichiro; Köpke, Sabrina; Kunert, Maritta; Volpe, Veronica; David, Anja; Brand, Peter; Dabrowska, Paulina; Maffei, Massimo E.; Boland, Wilhelm

    2008-01-01

    Continuous mechanical damage initiates the rhythmic emission of volatiles in lima bean (Phaseolus lunatus) leaves; the emission resembles that induced by herbivore damage. The effect of diurnal versus nocturnal damage on the initiation of plant defense responses was investigated using MecWorm, a robotic device designed to reproduce tissue damage caused by herbivore attack. Lima bean leaves that were damaged by MecWorm during the photophase emitted maximal levels of β-ocimene and (Z)-3-hexenyl acetate in the late photophase. Leaves damaged during the dark phase responded with the nocturnal emission of (Z)-3-hexenyl acetate, but with only low amounts of β-ocimene; this emission was followed by an emission burst directly after the onset of light. In the presence of 13CO2, this light-dependent synthesis of β-ocimene resulted in incorporation of 75% to 85% of 13C, demonstrating that biosynthesis of β-ocimene is almost exclusively fueled by the photosynthetic fixation of CO2 along the plastidial 2-C-methyl-d-erythritol 4-P pathway. Jasmonic acid (JA) accumulated locally in direct response to the damage and led to immediate up-regulation of the P. lunatus β-ocimene synthase gene (PlOS) independent of the phase, that is, light or dark. Nocturnal damage caused significantly higher concentrations of JA (approximately 2–3 times) along with enhanced expression levels of PlOS. Transgenic Arabidopsis thaliana transformed with PlOS promoter∷β-glucuronidase fusion constructs confirmed expression of the enzyme at the wounded sites. In summary, damage-dependent JA levels directly control the expression level of PlOS, regardless of light or dark conditions, and photosynthesis is the major source for the early precursors of the 2-C-methyl-d-erythritol 4-P pathway. PMID:18165324

  6. Alternative Green Solvents Project

    NASA Technical Reports Server (NTRS)

    Maloney, Phillip R.

    2012-01-01

    Necessary for safe and proper functioning of equipment. Mainly halogenated solvents. Tetrachloride, Trichloroethylene (TCE), CFC-113. No longer used due to regulatory/safety concerns. Precision Cleaning at KSC: Small % of total parts. Used for liquid oxygen (LOX) systems. Dual solvent process. Vertrel MCA (decafluoropentane (DFP) and trons-dichloroethylene) HFE-7100. DFP has long term environmental concerns. Project Goals: a) Identify potential replacements. b) 22 wet chemical processes. c) 3 alternative processes. d) Develop test procedures. e) Contamination and cleaning. f) Analysis. g) Use results to recommend alternative processes. Conclusions: a) No alternative matched Vertrel in this study. b) No clear second place solvent. c) Hydrocarbons- easy; Fluorinated greases- difficult. d) Fluorinated component may be needed in replacement solvent. e) Process may need to make up for shortcoming of the solvent. f) Plasma and SCC02 warrant further testing.

  7. Biodiesel: an alternative fuel.

    PubMed

    Manzanera, Maximino; Molina-Muñoz, Maria L; González-López, Jesús

    2008-01-01

    Biodiesel is an alternative energy source and could be a substitute for petroleum-based diesel fuel. To be a viable alternative, a biofuel should provide a net energy gain, have environmental benefits, be economically competitive, and be producible in large quantities without reducing food supplies. Most of the sources, methods and apparatus to produce biodiesel are reviewed here. Some of the patents propose the use of oils and fats of animal or vegetal origin and other kind of sources. Many others focus on the methods for the production or oxidation stability of the biofuel in order to make its production economically competitive. Several apparatus comprising reactors and refineries are also presented. This review article summarizes recent and important patents relating to the production of biodiesel to make its production a viable alternative.

  8. Alternative Fuels Infrastructure Development

    SciTech Connect

    Bloyd, Cary N.; Stork, Kevin

    2011-02-01

    This summary reviews the status of alternate transportation fuels development and utilization in Thailand. Thailand has continued to work to promote increased consumption of gasohol especially for highethanol content fuels like E85. The government has confirmed its effort to draw up incentives for auto makers to invest in manufacturing E85-compatible vehicles in the country. An understanding of the issues and experiences associated with the introduction of alternative fuels in other countries can help the US in anticipation potential problems as it introduces new automotive fuels.

  9. Solvent alternatives guide

    SciTech Connect

    Elion, J.M.; Monroe, K.R.; Hill, E.A.

    1996-06-01

    It is no longer legal to manufacture or import chlorofluorocarbon 113 or methyl chloroform solvents, and companies that currently clean their parts with either material are now required to implement environmentally safe substitutes. To help find alternative methods, Research Triangle Institute`s Surface Cleaning Technology Program has designed a Solvent Alternatives Guide (SAGE), an online tool that enables access to practical information and recommendations for acceptable solvents. Developed in partnership with the US Environmental Protection Agency, SAGE is available free of charge on the Internet`s World Wide Web.

  10. The energy cane alternative

    SciTech Connect

    Alexander, A.G.

    1985-01-01

    This book reviews the conceptual and theoretical background of Saccharum botany, which underlies the growing of cane as a total growth commodity. Management details are provided for energy cane planting, cultivation, harvest, and postharvest operations. Chapters on energy cane utilization stress new developments in lignocellulose conversion plus alternative options for fermentable solids usage. Chapters are also included for the management of alternative grasses to supplement energy cane, and the breeding of new hybrid canes with high biomass attributes at the intergeneric and interspecific levels.

  11. Alternatives in Education.

    ERIC Educational Resources Information Center

    Rusk, Bruce, Ed.

    These six lectures explore alternative approaches to education both within and outside the educational system. The contributions and their authors include: "Telling It Like It Ain't: An Examination of the Language of Education," by Neil Postman; "The Psychology of J. Piaget and Its Relevance to Education," by Vinh Bang (presented also in French);…

  12. Alternative Approaches to Negotiating.

    ERIC Educational Resources Information Center

    Ramming, Thomas M.

    1997-01-01

    The wait-and-react and laundry-list approaches to combating teachers' collective-bargaining demands are ineffective. An alternative goals-setting approach requires management and the district negotiations team to identify important needs and objectives. West Seneca Central School District ended contentious negotiations by presenting unions with…

  13. Environment and Alternative Development.

    ERIC Educational Resources Information Center

    Kothari, Rajni

    Stressing the global dimension to the adversary relationship between economic development and environmental conservation, this monograph examines the philosophical, historical, cultural, and ethnic underpinnings of modern science and technology. In addition, the monograph spells out policy implications of an alternative concept of development and…

  14. Independent Alternative Schools.

    ERIC Educational Resources Information Center

    Wohl, Seth F.

    Ten alternative high schools serving a total of 2,750 students in New York City were evaluated in terms of their administration, programs, student body, and specific educational objectives. Three main types of programs were in operation at the schools. These included: (1) Remediation with emphasis on basic skills in reading, mathematics and…

  15. Alternative energy technologies

    NASA Astrophysics Data System (ADS)

    Dresselhaus, M. S.; Thomas, I. L.

    2001-11-01

    Fossil fuels currently supply most of the world's energy needs, and however unacceptable their long-term consequences, the supplies are likely to remain adequate for the next few generations. Scientists and policy makers must make use of this period of grace to assess alternative sources of energy and determine what is scientifically possible, environmentally acceptable and technologically promising.

  16. Alternative Programming for Adults.

    ERIC Educational Resources Information Center

    Flint, Thomas A.; Frey, Ruth

    2003-01-01

    The Council for Adult and Experiential Learning is currently cataloguing alternative programming features that are most effective with adult students in a best practices inventory organized around a framework of high-level descriptive principles of effectiveness. This chapter identifies a few interesting features from a quick survey of this…

  17. Secondary Retention Alternative.

    ERIC Educational Resources Information Center

    Baenen, Nancy R.; Hopkins, Patricia

    Two alternatives to retention in grade for secondary school students were evaluated in Austin (Texas). Both were designed to allow students who are potential retainees (PRs) to receive remediation in one semester. The Transitional Academic Program (TAP) allows PRs to enroll in ninth-grade courses while repeating eighth-grade courses they had…

  18. Archive Storage Media Alternatives.

    ERIC Educational Resources Information Center

    Ranade, Sanjay

    1990-01-01

    Reviews requirements for a data archive system and describes storage media alternatives that are currently available. Topics discussed include data storage; data distribution; hierarchical storage architecture, including inline storage, online storage, nearline storage, and offline storage; magnetic disks; optical disks; conventional magnetic…

  19. A Better Alternative

    ERIC Educational Resources Information Center

    Knoeppel, Janet

    2007-01-01

    Mandated as an option for students who have not been successful in traditional programs, continuation education provides as alternative setting that helps students meet graduation requirements and earn their high school diplomas. Continuation high schools are quite successful in helping their students. This is due to their small size (usually 20:1…

  20. Augmentative & Alternative Communication

    ERIC Educational Resources Information Center

    Murphy, Patti

    2007-01-01

    There is no definitive recipe for augmentative and alternative communication (AAC) success, but its universal ingredients can be found at home. The main ones are: (1) Understanding that all children need to express themselves, however outgoing or shy they may be; (2) Willingness to embrace the technology that may help your child regardless of your…

  1. Alternatives in solar energy

    NASA Technical Reports Server (NTRS)

    Schueler, D. G.

    1978-01-01

    Although solar energy has the potential of providing a significant source of clean and renewable energy for a variety of applications, it is expected to penetrate the nation's energy economy very slowly. The alternative solar energy technologies which employ direct collection and conversion of solar radiation as briefly described.

  2. Alternative Energy Busing

    ERIC Educational Resources Information Center

    LaFee, Scott

    2012-01-01

    In recent years, school districts have converted portions of their bus fleets to cleaner-burning, sometimes cheaper, alternative fossil fuels, such as compressed natural gas or propane. Others have adopted biodiesel, which combines regular diesel with fuel derived from organic sources, usually vegetable oils or animal fats. The number of biodiesel…

  3. Energy conversion alternatives study

    NASA Technical Reports Server (NTRS)

    Shure, L. T.

    1979-01-01

    Comparison of coal based energy systems is given. Study identifies and compares various advanced energy conversion systems using coal or coal derived fuels for baselaoad electric power generation. Energy Conversion Alternatives Study (ECAS) reports provede government, industry, and general public with technically consistent basis for comparison of system's options of interest for fossilfired electric-utility application.

  4. Alternative Education Options.

    ERIC Educational Resources Information Center

    Little (Arthur D.), Inc., Washington, DC.

    This guide deals with various areas of alternative education programs, including current practices and different options available to school and community personnel. Steps are outlined to assess present educational settings, design new programs, select the participants, and implement and evaluate the new program. The first appendix contains…

  5. Compensated pulsed alternator

    DOEpatents

    Weldon, William F.; Driga, Mircea D.; Woodson, Herbert H.

    1980-01-01

    This invention relates to an electromechanical energy converter with inertial energy storage. The device, a single phase, two or multi-pole alternator with stationary field coils, and a rotating armature is provided. The rotor itself may be of laminated steel for slower pulses or for faster pulses should be nonmagnetic and electrically nonconductive in order to allow rapid penetration of the field as the armature coil rotates. The armature coil comprises a plurality of power generating conductors mounted on the rotor. The alternator may also include a stationary or counterrotating compensating coil to increase the output voltage thereof and to reduce the internal impedance of the alternator at the moment of peak outout. As the machine voltage rises sinusoidally, an external trigger switch is adapted to be closed at the appropriate time to create the desired output current from said alternator to an external load circuit, and as the output current passes through zero a self-commutating effect is provided to allow the switch to disconnect the generator from the external circuit.

  6. Finding alternatives to antibiotics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The spread of antibiotic-resistant pathogens requires new treatments. The availability of new antibiotics has severely declined, and so alternatives to antibiotics need to be considered in both animal agriculture and human medicine. Products for disease prevention are different than products for d...

  7. The SOLAR Alternative.

    ERIC Educational Resources Information Center

    Warren, E. H., Jr.; Walton, A. L.

    1984-01-01

    Only when the sun's energy can be captured at a comparable or lower opportunity cost than that of competing sources will solar energy systems become viable alternatives. Economic issues of solar energy are discussed. The legitimate role of government is also examined. (RM)

  8. Alternatives in Teacher Education.

    ERIC Educational Resources Information Center

    Clements, Millard

    This paper on alternatives in teacher education begins by analyzing the current emphasis on the scientific approach in education. The author finds the promise of the scientific approach to be illusory. He defines it as education that promotes behavior change in some desirable direction. However, this definition, which the author finds equally…

  9. Alternatives to Violence.

    ERIC Educational Resources Information Center

    Children Today, 1994

    1994-01-01

    Notes that our capacity to diffuse conflict rests in our ability to recognize and verbalize feelings, develop empathy, and think of alternatives to violence. Explores the influence of role models and culture on violence and how the media can use violent images effectively in helping us confront a culture of violence. (HTH)

  10. Alternatives to Evolutionism.

    ERIC Educational Resources Information Center

    Harper, G. H.

    1979-01-01

    Discusses alternative theories to evolutionism. Five theories are mentioned, but most attention is given to the steady state theory of species which the author considers the most suitable partner for Darwinism in O- and A-level biology courses in the United Kingdom. (HM)

  11. Alternative transportation fuels

    SciTech Connect

    Askew, W. S.; McNamara, T. M.; Maxfield, D. P.

    1980-01-01

    The commercialization of alternative fuels is analyzed. Following a synopsis of US energy use, the concept of commercialization, the impacts of supply shortages and demand inelasticity upon commercialization, and the status of alternative fuels commercialization to date in the US are discussed. The US energy market is viewed as essentially numerous submarkets. The interrelationship among these submarkets precludes the need to commercialize for a specific fuel/use. However, the level of consumption, the projected growth in demand, and the inordinate dependence upon foreign fuels dictate that additional fuel supplies in general be brought to the US energy marketplace. Commercialization efforts encompass a range of measures designed to accelerate the arrival of technologies or products in the marketplace. As discussed in this paper, such a union of willing buyers and willing sellers requires that three general conditions be met: product quality comparable to existing products; price competitiveness; and adequate availability of supply. Product comparability presently appears to be the least problematic of these three requirements. Ethanol/gasoline and methanol/gasoline blends, for example, demonstrate the fact that alternative fuel technologies exist. Yet price and availability (i.e., production capacity) remain major obstacles. Given inelasticity (with respect to price) in the US and abroad, supply shortages - actual or contrived - generate upward price pressure and should make once-unattractive alternative fuels more price competitive. It is noted, however, that actual price competitiveness has been slow to occur and that even with price competitiveness, the lengthy time frame needed to achieve significant production capacity limits the near-term impact of alternative fuels.

  12. Alternate dietary lifestyles.

    PubMed

    Krey, S H

    1982-09-01

    Various forms of vegetarian diets are discussed and evaluated for their nutritional adequacy. Health, philosophical, religious, ecological, and economic concerns are suggested as possible reasons for these alternate dietary lifestyles. Nutrients of specific concern ot the vegetarian are highlighted and suggestions given to help incorporate these in the diet, thereby avoiding marginal intakes. With judicious menu planning and careful thought to food selections, most vegetarian diets can supply excellent nutrition. Very restricted vegetarian diets or higher level macrobiotic diets may not be nutritionally complete, and individuals following these diets may benefit from special dietary counseling and dietary supplementation. Otherwise, these diets may place the adult as well as pregnant and lactating women, infants, and children at a nutritional risk. As vegetarian food habits are becoming more widespread, physicians and nutritionists must be knowledgeable about these alternate dietary lifestyles in order to counsel their patients appropriately, to understand the reasons for these eating habits, and to be supportive of the choice of diet.

  13. [Alternatives to animal testing].

    PubMed

    Fabre, Isabelle

    2009-11-01

    The use of alternative methods to animal testing are an integral part of the 3Rs concept (refine, reduce, replace) defined by Russel & Burch in 1959. These approaches include in silico methods (databases and computer models), in vitro physicochemical analysis, biological methods using bacteria or isolated cells, reconstructed enzyme systems, and reconstructed tissues. Emerging "omic" methods used in integrated approaches further help to reduce animal use, while stem cells offer promising approaches to toxicologic and pathophysiologic studies, along with organotypic cultures and bio-artificial organs. Only a few alternative methods can so far be used in stand-alone tests as substitutes for animal testing. The best way to use these methods is to integrate them in tiered testing strategies (ITS), in which animals are only used as a last resort.

  14. [Alternative hemodialysis regimens].

    PubMed

    Matos, Jorge Paulo Strogoff de; Lugon, Jocemir Ronaldo

    2010-03-01

    The mortality rate among patients on hemodialysis (HD) is extremely high. Remaining life expectancy for a patient initiating HD is only approximately one quarter of that of the general population at the same age bracket. The conventional HD regimen based on four-hour sessions three times a week was empirically established nearly four decades ago and needs to be revisited. Since the failure of the HEMO Study to demonstrate the clinical benefits of higher urea Kt/V for patients on conventional HD, an increasing interest for alternative HD regimens has emerged aiming at providing a treatment for improving survival rates. Short daily HD and long nocturnal HD stand out as the most promising alternative regimens. Economical obstacles which could hinder the clinical application of emerging knowledge in the field should be overcome.

  15. Alternative nanostructures for thermophones

    NASA Astrophysics Data System (ADS)

    Mayo, Nathanael; Aliev, Ali; Baughman, Ray

    2015-03-01

    There is a large promise for thermophones in high power sonar arrays, flexible loudspeakers, and noise cancellation devices. So far, freestanding aerogel-like carbon nanotube sheets demonstrate the best performance as a thermoacoustic heat source. However, the limited accessibility of large size freestanding carbon nanotube sheets and other even more exotic materials published recently, hampers the field. We present here new alternative materials for a thermoacoustic heat source with high energy conversion efficiency, additional functionalities, environmentally friendly and cost effective production technologies. We discuss the thermoacoustic performance of alternative nanoscale materials and compare their spectral and power dependencies of sound pressure in air. The study presented here focuses on engineering thermal gradients in the vicinity of nanostructures and subsequent heat dissipation processes from the interior of encapsulated thermoacoustic projectors. Applications of thermoacoustic projectors for high power SONAR arrays, sound cancellation, and optimal thermal design, regarding enhanced energy conversion efficiency, are discussed.

  16. Alternatives to ECMO.

    PubMed Central

    Donn, S M

    1994-01-01

    The past decade has witnessed technological advancements which are unparalleled in neonatology. ECMO has been demonstrated to be a powerful rescue treatment, but has perhaps been overutilised and is not universally available. Alternative treatments have been shown to be both safe and efficacious in the management of infants with respiratory failure. Direct head to head clinical trials will probably be necessary to establish appropriate criteria and indications for use, given the wide diversity of pathophysiology these unique patients present. PMID:7802759

  17. Outlook for alternative transportation fuels

    SciTech Connect

    Gushee, D.E.

    1996-12-31

    This presentation provides a brief review of regulatory issues and Federal programs regarding alternative fuel use in automobiles. A number of U.S. DOE initiatives and studies aimed at increasing alternative fuels are outlined, and tax incentives in effect at the state and Federal levels are discussed. Data on alternative fuel consumption and alternative fuel vehicle use are also presented. Despite mandates, tax incentives, and programs, it is concluded alternative fuels will have minimal market penetration. 7 refs., 5 tabs.

  18. State alternative route designations

    SciTech Connect

    Not Available

    1989-07-01

    Pursuant to the Hazardous Materials Transportation Act (HMTA), the Department of Transportation (DOT) has promulgated a comprehensive set of regulations regarding the highway transportation of high-level radioactive materials. These regulations, under HM-164 and HM-164A, establish interstate highways as the preferred routes for the transportation of radioactive materials within and through the states. The regulations also provide a methodology by which a state may select alternative routes. First,the state must establish a ``state routing agency,`` defined as an entity authorized to use the state legal process to impose routing requirements on carriers of radioactive material (49 CFR 171.8). Once identified, the state routing agency must select routes in accordance with Large Quantity Shipments of Radioactive Materials or an equivalent routing analysis. Adjoining states and localities should be consulted on the impact of proposed alternative routes as a prerequisite of final route selection. Lastly, the states must provide written notice of DOT of any alternative route designation before the routes are deemed effective.

  19. State alternative route designations

    SciTech Connect

    Not Available

    1989-07-01

    Pursuant to the Hazardous Materials Transportation Act (HMTA), the Department of Transportation (DOT) has promulgated a comprehensive set of regulations regarding the highway transportation of high-level radioactive materials. These regulations, under HM-164 and HM-164A, establish interstate highways as the preferred routes for the transportation of radioactive materials within and through the states. The regulations also provide a methodology by which a state may select alternative routes. First,the state must establish a state routing agency,'' defined as an entity authorized to use the state legal process to impose routing requirements on carriers of radioactive material (49 CFR 171.8). Once identified, the state routing agency must select routes in accordance with Large Quantity Shipments of Radioactive Materials or an equivalent routing analysis. Adjoining states and localities should be consulted on the impact of proposed alternative routes as a prerequisite of final route selection. Lastly, the states must provide written notice of DOT of any alternative route designation before the routes are deemed effective.

  20. THE ALTERNATIVE FOR SURVIVAL*

    PubMed Central

    Krishnakumar, P.R.

    1985-01-01

    The need of the time is to develop the traditional health care systems as a people oriented health care system. The factors that dominated the health care structure of our nation has been systematically pushing the traditional systems of medicine away from the people. In this background, an attempt has been made to reflect upon one's own experience, to understand the pattern of domination and to probe and suggest further on what could be the possible alternative development strategy and suggest specific tasks that would help define the development problematique in a meaningful manner in order to progress further in a self-determined manner PMID:22557469

  1. Potential alternate life biochemistries

    NASA Astrophysics Data System (ADS)

    Konesky, Gregory

    2013-09-01

    While life on Earth continues to be discovered in unlikely environments, the underlying biochemistry is all very similar, based on the element carbon, and requiring liquid water. We consider alternate biochemistries based on elements other than carbon, including other group IVA elements, such as silicon and germanium, and solvents other than water. Terminal electron acceptors other than oxygen are also discussed. A fundamental issue is raised related to the detection of, and even the definition of life, whether it is carbon or non-carbon based. An extreme example of this issue would be in consideration of speculative life based on electrically charged dusty plasmas, which may have no physical body.

  2. Alternative therapy in pruritus.

    PubMed

    Millikan, Larry E

    2003-01-01

    Because of its multitude of origins, the symptom complex of pruritus has a plethora of purported remedies and few therapeutic indications. Very few topical and systemic FDA approved medications have the indication of pruritus. Specific therapy still awaits a better definition of the exact physiologic events in chronic pruritus. Hence most medications actually focus on the central nervous system--the peripheral receptors--and the lack of specific physiologic targets has inhibited pharmacologic development. The resulting gap has opened the door to a variety of alternative therapies.

  3. Alternate fusion fuels workshop

    SciTech Connect

    Not Available

    1981-06-01

    The workshop was organized to focus on a specific confinement scheme: the tokamak. The workshop was divided into two parts: systems and physics. The topics discussed in the systems session were narrowly focused on systems and engineering considerations in the tokamak geometry. The workshop participants reviewed the status of system studies, trade-offs between d-t and d-d based reactors and engineering problems associated with the design of a high-temperature, high-field reactor utilizing advanced fuels. In the physics session issues were discussed dealing with high-beta stability, synchrotron losses and transport in alternate fuel systems. The agenda for the workshop is attached.

  4. Alternatives to eigenstate thermalization.

    PubMed

    Rigol, Marcos; Srednicki, Mark

    2012-03-16

    An isolated quantum many-body system in an initial pure state will come to thermal equilibrium if it satisfies the eigenstate thermalization hypothesis (ETH). We consider alternatives to ETH that have been proposed. We first show that von Neumann's quantum ergodic theorem relies on an assumption that is essentially equivalent to ETH. We also investigate whether, following a sudden quench, special classes of pure states can lead to thermal behavior in systems that do not obey ETH, namely, integrable systems. We find examples of this, but only for initial states that obeyed ETH before the quench.

  5. Alternative nanostructures for thermophones.

    PubMed

    Aliev, Ali E; Mayo, Nathanael K; Jung de Andrade, Monica; Robles, Raquel O; Fang, Shaoli; Baughman, Ray H; Zhang, Mei; Chen, Yongsheng; Lee, Jae Ah; Kim, Seon Jeong

    2015-05-26

    Thermophones are highly promising for applications such as high-power SONAR arrays, flexible loudspeakers, and noise cancellation devices. So far, freestanding carbon nanotube aerogel sheets provide the most attractive performance as a thermoacoustic heat source. However, the limited accessibility of large-size freestanding carbon nanotube aerogel sheets and other even more exotic materials recently investigated hampers the field. We describe alternative materials for a thermoacoustic heat source with high-energy conversion efficiency, additional functionalities, environmentally friendly, and cost-effective production technologies. We discuss the thermoacoustic performance of alternative nanostructured materials and compare their spectral and power dependencies of sound pressure in air. We demonstrate that the heat capacity of aerogel-like nanostructures can be extracted by a thorough analysis of the sound pressure spectra. The study presented here focuses on engineering thermal gradients in the vicinity of nanostructures and subsequent heat dissipation processes from the interior of encapsulated thermoacoustic projectors. Applications of thermoacoustic projectors for high-power SONAR arrays, sound cancellation, and optimal thermal design, regarding enhanced energy conversion efficiency, are discussed.

  6. Herbs, Supplements and Alternative Medicines

    MedlinePlus

    ... Living With Diabetes > Treatment and Care > Medication > Other Treatments > Herbs, Supplements, and Alternative Medicines Share: Print Page Text ... magazine: meds-other, In this section Medication Other Treatments Herbs, Supplements, and Alternative Medicines Types of Dietary Supplements ...

  7. Alternatives for Jet Engine Control

    NASA Technical Reports Server (NTRS)

    Leake, R. J.; Sain, M. K.

    1976-01-01

    Approaches are developed as alternatives to current design methods which rely heavily on linear quadratic and Riccati equation methods. The main alternatives are discussed in two broad categories, local multivariable frequency domain methods and global nonlinear optimal methods.

  8. Extending the Alternating Series Test

    ERIC Educational Resources Information Center

    Katsuura, Hidefumi

    2012-01-01

    Alternating series have the simplest of sign patterns. What about series with more complicated patterns? By inspecting the alternating series test closely, we find a theorem that applies to more complicated sign patterns, and beyond.

  9. Alternative aircraft fuels

    NASA Technical Reports Server (NTRS)

    Longwell, J. P.; Grobman, J.

    1978-01-01

    In connection with the anticipated impossibility to provide on a long-term basis liquid fuels derived from petroleum, an investigation has been conducted with the objective to assess the suitability of jet fuels made from oil shale and coal and to develop a data base which will allow optimization of future fuel characteristics, taking energy efficiency of manufacture and the tradeoffs in aircraft and engine design into account. The properties of future aviation fuels are examined and proposed solutions to problems of alternative fuels are discussed. Attention is given to the refining of jet fuel to current specifications, the control of fuel thermal stability, and combustor technology for use of broad specification fuels. The first solution is to continue to develop the necessary technology at the refinery to produce specification jet fuels regardless of the crude source.

  10. Comparing solar energy alternatives

    NASA Astrophysics Data System (ADS)

    White, J. R.

    1984-03-01

    This paper outlines a computational procedure for comparing the merits of alternative processes to convert solar radiation to heat, electrical power, or chemical energy. The procedure uses the ratio of equipment investment to useful work as an index. Comparisons with conversion counterparts based on conventional fuels are also facilitated by examining this index. The procedure is illustrated by comparisons of (1) photovoltaic converters of differing efficiencies; (2) photovoltaic converters with and without focusing concentrators; (3) photovoltaic conversion plus electrolysis vs photocatalysis for the production of hydrogen; (4) photovoltaic conversion plus plasma arcs vs photocatalysis for nitrogen fixation. Estimates for conventionally-fuelled processes are included for comparison. The reasons why solar-based concepts fare poorly in such comparisons are traced to the low energy density of solar radiation and its low stream time factor resulting from the limited number of daylight hours available and clouds obscuring the sun.

  11. Alternative energy sources

    NASA Astrophysics Data System (ADS)

    Todd, R. W.

    1982-04-01

    Renewable energy sources and their potential contribution for solving energy needs are presented. Centralized supply technologies include those alternative fuels derived from biomass using solar energy, (supplying 57% of the energy supply in some countries), and those using directly collected solar energy to manufacture a fuel. Fuel utilization effects can be doubled by using combined heat and power stations, and other major sources include wind, wave, tidal, and solar. In terms of local supply technology, wood burning appliances are becoming more popular, and methane is being used for heating and to fuel spark ignition engines. Geothermal low temperature heating exists worldwide at a capacity of 7.2 GW, supplying heat, particularly in Hungary, parts of the U.S.S.R., and Iceland, and a geothermal research program has been established in the United States. Sweden has a potential hydroelectric capacity of 600 MW, and the United States has a 100 GW capacity. Many of these technologies are already cost effective.

  12. Alkalis in alternative biofuels

    SciTech Connect

    Miles, T.R.; Miles, T.R. Jr.; Bryers, R.W.; Baxter, L.L.; Jenkins, B.M.; Oden, L.L.

    1994-12-31

    The alkali content and behavior of inorganic material of annually produced biofuels severely limits their use for generating electrical power in conventional furnaces. A recent eighteen-month investigation of the chemistry and firing characteristics of 26 different biofuels has been conducted. Firing conditions were simulated in the laboratory for eleven biofuels. This paper describes some results from the investigation including fuel properties, deposits, deposition mechanisms, and implications for biomass boiler design, fuel sampling and characterizations. Urban wood fuel, agricultural residues, energy crops, and other potential alternate fuels are included in the study. Conventional methods for establishing fuel alkali content and determining ash sticky temperatures were deceptive. The crux of the problem was found to be the high concentration of potassium in biofuels and its reactions with other fuel constituents which lower the ``sticky temperature`` of the ash to the 650 C to 760 C (1,200 F-1,400 F).

  13. Exploring new energy alternatives.

    SciTech Connect

    LePoire, D.J.

    2011-09-01

    What is most likely to satisfy our energy needs in the future - wind farms and photovoltaic arrays, or something yet to be invented? Options for the world's energy future may include surprises, thanks to innovative research under way around the world. The article focuses on the energy sources alternatives in the U.S. It explores innovations for energy sources such as wind farms, solar thermal concentrators, solar cells, and geothermal energy production. It states that the attainment of energy efficiency through conversation or improved technology allows to extract more applied energy. It points out that techniques are being explored to expand the possible fuel materials to includes other types of uranium and thorium. Furthermore, it discusses the capability of nanotechnology in offering a tool which could help create designs that convert energy more efficiently.

  14. Alternative Fuels Research Laboratory

    NASA Technical Reports Server (NTRS)

    Surgenor, Angela D.; Klettlinger, Jennifer L.; Nakley, Leah M.; Yen, Chia H.

    2012-01-01

    NASA Glenn has invested over $1.5 million in engineering, and infrastructure upgrades to renovate an existing test facility at the NASA Glenn Research Center (GRC), which is now being used as an Alternative Fuels Laboratory. Facility systems have demonstrated reliability and consistency for continuous and safe operations in Fischer-Tropsch (F-T) synthesis and thermal stability testing. This effort is supported by the NASA Fundamental Aeronautics Subsonic Fixed Wing project. The purpose of this test facility is to conduct bench scale F-T catalyst screening experiments. These experiments require the use of a synthesis gas feedstock, which will enable the investigation of F-T reaction kinetics, product yields and hydrocarbon distributions. Currently the facility has the capability of performing three simultaneous reactor screening tests, along with a fourth fixed-bed reactor for catalyst activation studies. Product gas composition and performance data can be continuously obtained with an automated gas sampling system, which directly connects the reactors to a micro-gas chromatograph (micro GC). Liquid and molten product samples are collected intermittently and are analyzed by injecting as a diluted sample into designated gas chromatograph units. The test facility also has the capability of performing thermal stability experiments of alternative aviation fuels with the use of a Hot Liquid Process Simulator (HLPS) (Ref. 1) in accordance to ASTM D 3241 "Thermal Oxidation Stability of Aviation Fuels" (JFTOT method) (Ref. 2). An Ellipsometer will be used to study fuel fouling thicknesses on heated tubes from the HLPS experiments. A detailed overview of the test facility systems and capabilities are described in this paper.

  15. A new quenching alternative

    SciTech Connect

    Brennan, R.J.; Faulkner, C.H.

    1996-12-31

    The quenching of ferrous alloys implies the controlled extraction of heat from a part at a rate sufficient to harden the part and still control the desired dimensional limitations. Quenchants in common use today are: molten metals, molten salts, petroleum oils, polymer solutions, water, and salt/water solutions. Each type of quenchant has its benefits and limitations. With current waste legislation and the trends toward environmentally friendlier industrial working fluids, many of these quenching products are coming under close scrutiny by the users and legislators. The most widely used quenchant is petroleum oil due to its favorable heat extraction characteristics. The dependence upon imports, price vulnerability, and contamination potential have caused suppliers and users to look into alternative products. Research into renewable resource, non-petroleum, vegetable oils has been going on globally for several years. The drawbacks encountered with many vegetable oils were widely known and only years of research enabled them to be overcome. The presently formulated product not only performs as well as petroleum oil but shows some characteristics better than those of the petroleum products, especially in the biodegradability and ecological aspects of the products. Stability and reproducible quenching properties have been proven with over two and one half years of field testing.

  16. Alternative Compression Garments

    NASA Technical Reports Server (NTRS)

    Stenger, M. B.; Lee, S. M. C.; Ribeiro, L. C.; Brown, A. K.; Westby, C. M.; Platts, S. H.

    2011-01-01

    Orthostatic intolerance after spaceflight is still an issue for astronauts as no in-flight countermeasure has been 100% effective. Future anti-gravity suits (AGS) may be similar to the Shuttle era inflatable AGS or may be a mechanical compression device like the Russian Kentavr. We have evaluated the above garments as well as elastic, gradient compression garments of varying magnitude and determined that breast-high elastic compression garments may be a suitable replacement to the current AGS. This new garment should be more comfortable than the AGS, easy to don and doff, and as effective a countermeasure to orthostatic intolerance. Furthermore, these new compression garments could be worn for several days after space flight as necessary if symptoms persisted. We conducted two studies to evaluate elastic, gradient compression garments. The purpose of these studies was to evaluate the comfort and efficacy of an alternative compression garment (ACG) immediately after actual space flight and 6 degree head-down tilt bed rest as a model of space flight, and to determine if they would impact recovery if worn for up to three days after bed rest.

  17. Enhanced Design Alternative IV

    SciTech Connect

    N. E. Kramer

    1999-05-18

    This report evaluates Enhanced Design Alternative (EDA) IV as part of the second phase of the License Application Design Selection (LADS) effort. The EDA IV concept was compared to the VA reference design using criteria from the ''Design Input Request for LADS Phase II EDA Evaluations'' (CRWMS M&O 1999b) and (CRWMS M&O 1999f). Briefly, the EDA IV concept arranges the waste packages close together in an emplacement configuration known as ''line load''. Continuous pre-closure ventilation keeps the waste packages from exceeding the 350 C cladding and 200 C (4.3.13) drift wall temperature limits. This EDA concept keeps relatively high, uniform emplacement drift temperatures (post-closure) to drive water away from the repository and thus dry out the pillars between emplacement drifts. The waste package is shielded to permit human access to emplacement drifts and includes an integral filler inside the package to reduce the amount of water that can contact the waste form. Closure of the repository is desired 50 years after first waste is emplaced. Both backfill and a drip shields will be emplaced at closure to improve post-closure performance.

  18. Diesel Engine Alternatives

    SciTech Connect

    Ryan, T

    2003-08-24

    There are basically three different modes of combustion possible for use in reciprocating engines. These include, diffusion burning, as occurs in current diesel engines, flame propagation combustion such as used in conventional SI engines, and homogeneous combustion such as is used in the SwRI HCCI engine. Diesel engines currently offer significant fuel consumption benefits relative to other powerplants for on and off road applications; however, costs and efficiency may become problems as the emissions standards become even more stringent. This presentation presents a discussion of the potentials of HCCI and flame propagation engines as alternatives to the diesel engines. It is suggested that as the emissions standards become more and more stringent, the advantages of the diesel may disappear. The potential for HCCI is limited by the availability of the appropriate fuel. The potential of flame propagation engines is limited by several factors including knock, EGR tolerance, high BMEP operation, and throttling. These limitations are discussed in the context of potential for improvement of the efficiency of the flame propagation engine.

  19. Alternating hemiplegia of childhood.

    PubMed

    Kansagra, Sujay; Mikati, Mohamad A; Vigevano, Federico

    2013-01-01

    Alternating hemiplegia of childhood (AHC) is a very rare disease characterized by recurrent attacks of loss of muscular tone resulting in hypomobility of one side of the body. The etiology of the disease due to ATP1A3 gene mutations in the majority of patients. Few familial cases have been described. AHC has an onset in the first few months of life. Hemiplegic episodes are often accompanied by other paroxysmal manifestations, such as lateral eyes and head deviation toward the hemiplegic side and a very peculiar monocular nystagmus. As the attack progresses, hemiplegia can shift to the other side of the body. Sometimes the attack can provoke bilateral paralysis, and these patients may have severe clinical impairment, with difficulty in swallowing and breathing. Hemiplegic attacks may be triggered by different stimuli, like bath in warm water, motor activity, or emotion. The frequency of attacks is high, usually several in a month or in a week. The duration is variable from a few minutes to several hours or even days. Sleep can stop the attack. Movement disorders such as dystonia and abnormal movements are frequent. Cognitive delay of variable degree is a common feature. Epilepsy has been reported in 50% of the cases, but seizure onset is usually during the third or fourth year of life. Many drugs have been used in AHC with very few results. Flunarizine has the most supportive anecdotal evidence regarding efficacy.

  20. [Alternative oxidase in industrial fungi].

    PubMed

    Gu, Shuai; Liu, Qiang; He, Hao; Li, Shuang

    2015-01-01

    Filamentous fungi have been used in industrial fermentation extensively. Based on non-phosphorylating electron transport process, alternative respiration pathway (ARP) acts as an energy overflow, which can balance carbon metabolism and electron transport, allow the continuance of tricarboxylic acid cycle without the formation of ATP, and permit the turnover of carbon skeletons. Alternative respiration pathway also plays an important role in the stress response of fungi and the physiological function of conditioned pathogen. Alternative oxidase (AOX) is the terminal oxidase responsible for the activity of alternative respiration pathway, which exists widely in higher plants, parts of fungi and algae. Owing to the property that alternative oxidase (AOX) is sensitive to salicylhydroxamic acid (SHAM) and insensitive to conventional inhibitors of cytochrome respiration, alternative respiration pathway by AOX is also named as cyanide-resistant respiration (CRR). In recent years, the study of the alternative respiration pathway and alternative oxidase has been a hot topic in the area involving cellular respiration metabolism. In this review we summarized the latest research advances about the functions of alternative respiration pathway and alternative oxidase in industrial fungi.

  1. Complementary and alternative medicine

    PubMed Central

    Gaboury, Isabelle; Johnson, Noémie; Robin, Christine; Luc, Mireille; O’Connor, Daniel; Patenaude, Johane; Pélissier-Simard, Luce; Xhignesse, Marianne

    2016-01-01

    Abstract Objective To determine whether medical training prepares FPs to meet the requirements of the Collège des médecins du Québec for their role in advising patients on the use of complementary and alternative medicine (CAM). Design Secondary analysis of survey results. Setting Quebec. Participants Family physicians and GPs in active practice. Main outcome measures Perceptions of the role of the physician as an advisor on CAM; level of comfort responding to questions and advising patients on CAM; frequency with which patients ask their physicians about CAM; personal position on CAM; and desire for training on CAM. Results The response rate was 19.5% (195 respondents of 1000) and the sample appears to be representative of the target population. Most respondents (85.8%) reported being asked about CAM several times a month. A similar proportion (86.7%) believed it was their role to advise patients on CAM. However, of this group, only 33.1% reported being able to do so. There is an association between an urban practice and knowledge of the advisory role of physicians. More than three-quarters of respondents expressed interest in receiving additional training on CAM. Conclusion There is a gap between the training that Quebec physicians receive on CAM and their need to meet legal and ethical obligations designed to protect the public where CAM products and therapies are concerned. One solution might be more thorough training on CAM to help physicians meet the Collège des médecins du Québec requirements. PMID:27965354

  2. Alternating gradient photodetector

    NASA Technical Reports Server (NTRS)

    Overhauser, Albert W. (Inventor); Maserjian, Joseph (Inventor)

    1989-01-01

    A far infrared (FIR) range responsive photodetector is disclosed. There is a substrate of degenerate germanium. A plurality of alternating impurity-band and high resistivity layers of germanium are disposed on the substrate. The impurity-band layers have a doping concentration therein sufficiently high to include donor bands which can release electrons upon impingement by FIR photons of energy hv greater than an energy gap epsilon. The high resistivity layers have a doping concentration therein sufficiently low as to not include conducting donor bands and are depleted of electrons. Metal contacts are provided for applying an electrical field across the substrate and the plurality of layers. In the preferred embodiment as shown, the substrate is degenerate n-type (N++) germanium; the impurity-band layers are n+ layers of germanium doped to approximately the low 10(exp 16)/cu cm range; and, the high resistivity layers are n-layers of germanium doped to a maximum of approximately 10(exp)/cu cm. Additionally, the impurity-band layers have a thickness less than a conduction-electron diffusion length in germanium and likely to be in the range of 0.1 to 1.0 micron, the plurality of impurity-bands is of a number such that the flux of FIR photons passing therethrough will be substantially totally absorbed therein, the thickness of the high resistivity layers is such compared to the voltage applied that the voltage drop in each the high resistivity layers controls the occurence of impact ionization in the impurity-band layers to a desired level.

  3. Synthetic and Alternate Fuels Characterization

    DTIC Science & Technology

    1988-02-01

    e-e AD-A197 531 AD_ m iI ORNL/TM-10706 OAK RIDGE NATIONAL Synthetic and Alternate LABORATORY Fuels Characterization •_ _ __ _ _Final Report February...21701-5012 62787A 2787A878 CA 294 11 TITLE (Include Security Classification) Synthetic and Alternate Fuels Characterization 12 PERSONAL AUTHOR(S) W. H...results suggest that highly refined and finished mobility fuels from synthetic or alternate sources will not pose a significantly greater toxicological

  4. Alternative display and interaction devices

    NASA Technical Reports Server (NTRS)

    Bolas, M. T.; McDowall, I. E.; Mead, R. X.; Lorimer, E. R.; Hackbush, J. E.; Greuel, C.

    1995-01-01

    While virtual environment systems are typically thought to consist of a head mounted display and a flex-sensing glove, alternative peripheral devices are beginning to be developed in response to application requirements. Three such alternatives are discussed: fingertip sensing gloves, fixed stereoscopic viewers, and counterbalanced head mounted displays. A subset of commercial examples that highlight each alternative is presented as well as a brief discussion of interesting engineering and implementation issues.

  5. Alternative fuelds in urban fleets

    SciTech Connect

    Lindsay, T.

    1994-12-31

    In this presentation the author addresses four main objectives. They are to: discuss programs that are driving the introduction of alternative fuels into fleet operations in urban areas around the country; define alternative fuels; quantify the present use and future projections on alternative fuel vehicles (AVFs) in the Chicago metropolitan statistical area; and discuss benefits of increased use of alternative fuels in urban areas. Factors which touch on these points include: present domestic dependence on petroleum for autos, with usage exceeding production; the large populations in urban areas which do not meet Clean Air Standards; recent legislative initiatives which give guidance and aid in the adoption of such strategies.

  6. Alternative RNA splicing and cancer.

    PubMed

    Liu, Sali; Cheng, Chonghui

    2013-01-01

    Alternative splicing of pre-messenger RNA (mRNA) is a fundamental mechanism by which a gene can give rise to multiple distinct mRNA transcripts, yielding protein isoforms with different, even opposing, functions. With the recognition that alternative splicing occurs in nearly all human genes, its relationship with cancer-associated pathways has emerged as a rapidly growing field. In this review, we summarize recent findings that have implicated the critical role of alternative splicing in cancer and discuss current understandings of the mechanisms underlying dysregulated alternative splicing in cancer cells.

  7. Normetex Pump Alternatives Study

    SciTech Connect

    Clark, Elliot A.

    2013-04-25

    A mainstay pump for tritium systems, the Normetex scroll pump, is currently unavailable because the Normetex company went out of business. This pump was an all-metal scroll pump that served tritium processing facilities very well. Current tritium system operators are evaluating replacement pumps for the Normetex pump and for general used in tritium service. An all-metal equivalent alternative to the Normetex pump has not yet been identified. 1. The ideal replacement tritium pump would be hermetically sealed and contain no polymer components or oils. Polymers and oils degrade over time when they contact ionizing radiation. 2. Halogenated polymers (containing fluorine, chlorine, or both) and oils are commonly found in pumps. These materials have many properties that surpass those of hydrocarbon-based polymers and oils, including thermal stability (higher operating temperature) and better chemical resistance. Unfortunately, they are less resistant to degradation from ionizing radiation than hydrocarbon-based materials (in general). 3. Polymers and oils can form gaseous, condensable (HF, TF), liquid, and solid species when exposed to ionizing radiation. For example, halogenated polymers form HF and HCl, which are extremely corrosive upon reaction with water. If a pump containing polymers or oils must be used in a tritium system, the system must be designed to be able to process the unwanted by-products. Design features to mitigate degradation products include filters and chemical or physical traps (eg. cold traps, oil traps). 4. Polymer components can work in tritium systems, but must be replaced regularly. Polymer components performance should be monitored or be regularly tested, and regular replacement of components should be viewed as an expected normal event. A radioactive waste stream must be established to dispose of used polymer components and oil with an approved disposal plan developed based on the facility location and its regulators. Polymers have varying

  8. Alternative Funerals: An Exploratory Study.

    ERIC Educational Resources Information Center

    Bergen, M. Betsy; Williams, Robert R.

    1981-01-01

    Studied attitudes and beliefs related to death and funeral preferences in a small midwestern Protestant congregation. While most respondents felt a ceremony or funeral was important, 75 percent preferred an alternative to the conventional funeral. Alternatives considered building a simple coffin with private burial and later public ceremony.…

  9. Saving Money with Menu Alternatives.

    ERIC Educational Resources Information Center

    Rubin, David

    1998-01-01

    Menu alternatives are substitute meals, whereas menu additions are dishes that complement the main meal. Both should be vegetarian dishes that are less expensive than the main offering and attractive to 20-40% of the camp population. By offering alternatives and additions, one can eliminate complaints, save money, and change eating patterns.…

  10. Alternative Programs for Disruptive Youth.

    ERIC Educational Resources Information Center

    Thomas, M. Angele, Ed.; And Others

    The book addresses issues in meeting the educational needs of disruptive students. In the introduction, R. Sarri examines the rise of alternative schools and discusses common elements in their design and operation. D. Sabatino follows with "Issues and Concerns: Problems with Alternative Schools," in which he examines the particular difficulties…

  11. Orion Project: Alternate Attitude Study

    NASA Technical Reports Server (NTRS)

    Alvarez-Hernandez, A.; Miller, Stephen W.

    2009-01-01

    This slide presentation reviews the study done on alternate attitudes for the Orion project's crew exploration vehicle. The analysis focused on the thermal performance of the vehicle with the alternate attitudes. The pressure vessel heater power, other vehicle heaters and radiator sink temperatures were included in the analysis.

  12. Rural Inservice Using Alternate Scheduling.

    ERIC Educational Resources Information Center

    Kimmet, James L.

    Three small rural school districts in Montana and Wyoming used alternate school day scheduling to make time for staff and curriculum development inservice programs. The schedule of one short and four long days delivered the instructional time of 175 6-hour days each year. Benefits of alternate scheduling included time for regular inservice…

  13. The Alternative Press in Microform.

    ERIC Educational Resources Information Center

    Tsang, Daniel C.

    Presented is an analysis of what has been done regarding the preservation of alternative publications in microfilm. The alternative press was defined, for the purposes of this study, as "nonstandard, nonestablishment publications." Two projects undertaken to microfilm such publications, one by the Microphoto Division of Bell and Howell…

  14. Alternative Teacher Certification in Texas.

    ERIC Educational Resources Information Center

    Texas Education Agency, Austin.

    This publication describes alternative teacher certification programs in Texas that train interns who are generally mature, mid-career individuals. The document is organized into seven sections: (1) "Alternative Certification in Texas" discusses the history and background of the programs including legislation, the first alternative…

  15. Alternate Semester 1972. An Evaluation.

    ERIC Educational Resources Information Center

    Copp, Barry D.; And Others

    Five students from a Boston high school and 35 from Lincoln-Sudbury took part in an alternate semester consisting of 5 units: Outward Bound, environmental issues, urban, rural, and river/building. Students had to be juniors or seniors, have parental permission, and meet graduation requirements. The alternate semester began with Outward Bound, a…

  16. Complementary and Alternative Methods and Cancer

    MedlinePlus

    ... Effects Complementary and Alternative Medicine Complementary and Alternative Methods and Cancer Complementary and alternative are terms used ... with cancer here. What Are Complementary and Alternative Methods? How Are Complementary Methods Used to Manage Cancer? ...

  17. Considerations for Equating Alternate Assessments: Two Case Studies of Alternate Assessments Based on Alternate Achievement Standards

    ERIC Educational Resources Information Center

    Wyse, Adam E.; Dean, Vincent J.; Viger, Steven G.; Vansickle, Timothy R.

    2013-01-01

    The development of alternate assessments for students with disabilities plays a pivotal role in state and national accountability systems. An important assumption in the use of alternate assessments in these accountability systems is that scores are comparable on different test forms across diverse groups of students over time. The use of test…

  18. NASA Alternative Aviation Fuel Research

    NASA Astrophysics Data System (ADS)

    Anderson, B. E.; Beyersdorf, A. J.; Thornhill, K. L., II; Moore, R.; Shook, M.; Winstead, E.; Ziemba, L. D.; Crumeyrolle, S.

    2015-12-01

    We present an overview of research conducted by NASA Aeronautics Research Mission Directorate to evaluate the performance and emissions of "drop-in" alternative jet fuels, highlighting experiment design and results from the Alternative Aviation Fuel Experiments (AAFEX-I & -II) and Alternative Fuel-Effects on Contrails and Cruise Emissions flight series (ACCESS-I & II). These projects included almost 100 hours of sampling exhaust emissions from the NASA DC-8 aircraft in both ground and airborne operation and at idle to takeoff thrust settings. Tested fuels included Fischer-Tropsch (FT) synthetic kerosenes manufactured from coal and natural-gas feedstocks; Hydro-treated Esters and Fatty-Acids (HEFA) fuels made from beef-tallow and camelina-plant oil; and 50:50 blends of these alternative fuels with Jet A. Experiments were also conducted with FT and Jet A fuels doped with tetrahydrothiophene to examine the effects of fuel sulfur on volatile aerosol and contrail formation and microphysical properties. Results indicate that although the absence of aromatic compounds in the alternative fuels caused DC-8 fuel-system leaks, the fuels did not compromise engine performance or combustion efficiency. And whereas the alternative fuels produced only slightly different gas-phase emissions, dramatic reductions in non-volatile particulate matter (nvPM) emissions were observed when burning the pure alternative fuels, particularly at low thrust settings where particle number and mass emissions were an order of magnitude lower than measured from standard jet fuel combustion; 50:50 blends of Jet A and alternative fuels typically reduced nvPM emissions by ~50% across all thrust settings. Alternative fuels with the highest hydrogen content produced the greatest nvPM reductions. For Jet A and fuel blends, nvPM emissions were positively correlated with fuel aromatic and naphthalene content. Fuel sulfur content regulated nucleation mode aerosol number and mass concentrations within aging

  19. Peat as an energy alternative

    SciTech Connect

    Punwani, D.V.

    1980-07-01

    The importance of developing alternative energy sources to augment supplies of fossil fuels is growing all over the world. Coal, oil shale, tar sands, biomass, solar, geothermal, nuclear, and hydroelectric power have received considerable attention as alternative energy sources. One large energy resource, however, has received little attention until recently. That resource is peat. Although peat is used as an energy source in some countries such as Russia, Ireland, and Finland, it is virtually unexploited in many countries including the United States. This paper provides an understanding of peat: its varieties, abundance, and distribution; its value as an energy alternative; its current and future role as an energy alternative; and the environmental and socioeconomic impacts of large-scale peat utilization.

  20. Disturbance maintains alternative biome states.

    PubMed

    Dantas, Vinícius de L; Hirota, Marina; Oliveira, Rafael S; Pausas, Juli G

    2016-01-01

    Understanding the mechanisms controlling the distribution of biomes remains a challenge. Although tropical biome distribution has traditionally been explained by climate and soil, contrasting vegetation types often occur as mosaics with sharp boundaries under very similar environmental conditions. While evidence suggests that these biomes are alternative states, empirical broad-scale support to this hypothesis is still lacking. Using community-level field data and a novel resource-niche overlap approach, we show that, for a wide range of environmental conditions, fire feedbacks maintain savannas and forests as alternative biome states in both the Neotropics and the Afrotropics. In addition, wooded grasslands and savannas occurred as alternative grassy states in the Afrotropics, depending on the relative importance of fire and herbivory feedbacks. These results are consistent with landscape scale evidence and suggest that disturbance is a general factor driving and maintaining alternative biome states and vegetation mosaics in the tropics.

  1. Alternatives. How to Avoid ID.

    ERIC Educational Resources Information Center

    Thiagarajan, Sivasailam

    1984-01-01

    Three alternatives to instructional development are briefly described: shifting more instructional responsibility from developer to learner; implementing an instructional system utilizing paraprofessionals, content experts, and peers; and selecting and adapting existing instructional materials. (MBR)

  2. Clear Thinking about Alternative Therapies

    MedlinePlus

    ... industry, with corporations both large and small vigorously marketing their products. 5 | Clear Thinking about Alternative Therapies ... Once the FDA has cleared the product for marketing, people are protected by disclosure requirements such as ...

  3. Alternative fuels for road vehicles

    SciTech Connect

    Poulton, M.L.

    1994-12-31

    The finite nature of global fossil fuel resources underscores the need to develop alternative vehicular fuels. Increased use of renewable and alternative fuels can extend fossil fuel supplies and help resolve air pollution problems inherent in automotive use of conventional fuels. Fuel characteristics, safety implications, feedstocks, infrastructure, fuel production costs, emissions performance, required vehicle modifications, and outlook are described for LPG, reformulated gasoline, natural gas, hydrogen, electricity, biofuels, ethanol, and methanol. 26 fig., 288 refs., 29 tabs.

  4. Alternative approaches to plasma confinement

    NASA Technical Reports Server (NTRS)

    Roth, J. R.

    1977-01-01

    The potential applications of fusion reactors, the desirable properties of reactors intended for various applications, and the limitations of the Tokamak concept are discussed. The principles and characteristics of 20 distinct alternative confinement concepts are described, each of which may be an alternative to the Tokamak. The devices are classed as Tokamak-like, stellarator-like, mirror machines, bumpy tori, electrostatically assisted, migma concept, and wall-confined plasma.

  5. State Energy Alternatives: Alternative Energy Resources by State

    DOE Data Explorer

    This U.S. map provides state by state information on incentives and laws related to alternative fuels and advanced vehicles. Discover what's available in each state for innovation grants, infrastructure grants, and production grants and who to contact. Find out how many alternative refueling stations are available in each state and where they are. Tennessee, for example, in 2009, has 114 alternative refueling stations: 36 biodiesel, 1 electrical, 29 ethanol, 4 natural gas, and 44 propane. There are also 5 Truck Stop Electrification (TSE) sites in Tennessee. Users can also find out from this map interface the contacts for Clean Cities in a state, information about renewable energy projects and activities in each state, fuel prices across a state, and biomass potential resources and current production in each state.

  6. Autocratic strategies for alternating games.

    PubMed

    McAvoy, Alex; Hauert, Christoph

    2017-02-01

    Repeated games have a long tradition in the behavioral sciences and evolutionary biology. Recently, strategies were discovered that permit an unprecedented level of control over repeated interactions by enabling a player to unilaterally enforce linear constraints on payoffs. Here, we extend this theory of "zero-determinant" (or, more generally, "autocratic") strategies to alternating games, which are often biologically more relevant than traditional synchronous games. Alternating games naturally result in asymmetries between players because the first move matters or because players might not move with equal probabilities. In a strictly-alternating game with two players, X and Y, we give conditions for the existence of autocratic strategies for player X when (i) X moves first and (ii) Y moves first. Furthermore, we show that autocratic strategies exist even for (iii) games with randomly-alternating moves. Particularly important categories of autocratic strategies are extortionate and generous strategies, which enforce unfavorable and favorable outcomes for the opponent, respectively. We illustrate these strategies using the continuous Donation Game, in which a player pays a cost to provide a benefit to the opponent according to a continuous cooperative investment level. Asymmetries due to alternating moves could easily arise from dominance hierarchies, and we show that they can endow subordinate players with more autocratic strategies than dominant players.

  7. Alternative splicing interference by xenobiotics.

    PubMed

    Zaharieva, Emanuela; Chipman, J Kevin; Soller, Matthias

    2012-06-14

    The protein coding sequence of most eukaryotic genes (exons) is interrupted by non-coding parts (introns), which are excised in a process termed splicing. To generate a mature messenger RNA (mRNA) hundreds of combinatorial protein-protein and RNA-protein interactions are required to splice out often very large introns with high fidelity and accuracy. Inherent to splicing is the use of alternative splice sites generating immense proteomic diversity from a limited number of genes. In humans, alternative splicing is a major mode of regulating gene expression, occurs in over 90% of genes and is particularly abundant in the brain. Only recently, it has been recognized that the complexity of the splicing process makes it susceptible to interference by various xenobiotics. These compounds include antineoplastic substances, commonly used drugs and food supplements and cause a spectrum of effects ranging from deleterious inhibition of general splicing to highly specific modifications of alternative splicing affecting only certain genes. Alterations in splicing have been implicated in numerous diseases such as cancer and neurodegeneration. Splicing regulation plays an important role in the execution of programmed cell death. The switch between anti- and pro-apoptotic isoforms by alternative splice site selection and misregulation of a number of splicing factors impacts on cell survival and disease. Here, our current knowledge is summarized on compounds interfering with general and alternative splicing and of the current methodology to study changes in these processes relevant to the field of toxicology and future risk assessments.

  8. Advances in alternative cementitious binders

    SciTech Connect

    Juenger, M.C.G.; Winnefeld, F.; Provis, J.L.; Ideker, J.H.

    2011-12-15

    There is a burgeoning interest in the development, characterization, and implementation of alternatives to Portland cement as a binder in concrete. The construction materials industry is under increasing pressure to reduce the energy used in production of Portland cement clinker and the associated greenhouse gas emissions. Further, Portland cement is not the ideal binder for all construction applications, as it suffers from durability problems in particularly aggressive environments. Several alternative binders have been available for almost as long as Portland cement, yet have not been extensively used, and new ones are being developed. In this paper, four promising binders available as alternatives to Portland cement are discussed, namely calcium aluminate cement, calcium sulfoaluminate cement, alkali-activated binders, and supersulfated cements. The history of the binders, their compositions and reaction mechanisms, benefits and drawbacks, unanswered questions, and primary challenges are described.

  9. Experiences in mainstreaming alternative energy

    SciTech Connect

    Cabraal, A.

    1997-12-01

    The author discusses efforts by the Asia Alternative Energy Unit (ASTAE) of the World Bank in supporting alternative energy source projects in Asia. Energy growth rates have been as high as 18% per year, with power capacity doubling each decade in the 1960`s, 70`s and 80`s. Much of this has come from fossil fuel projects coupled with major hydroelectric projects. One consequence is developing air pollution loads originating in Asia. ASTAE has been supporting pilot programs in applying alternative energy sources. The goal has been to mainstream renewable energy sources in World Bank operations, by working with managers from different countries to: include renewable energy in country assistance strategies and sectorial development plans; provide assistance to renewable energy initiatives; expand initiatives to new countries, sectors and technologies.

  10. Coupling transcription and alternative splicing.

    PubMed

    Kornblihtt, Alberto R

    2007-01-01

    Alternative splicing regulation not only depends on the interaction of splicing factors with splicing enhancers and silencers in the pre-mRNA, but also on the coupling between transcription and splicing. This coupling is possible because splicing is often cotranscriptional and promoter identity and occupation may affect alternative splicing. We discuss here the different mechanisms by which transcription regulates alternative splicing. These include the recruitment of splicing factors to the transcribing polymerase and "kinetic coupling", which involves changes in the rate of transcriptional elongation that in turn affect the timing in which splice sites are presented to the splicing machinery. The recruitment mechanism may depend on the particular features of the carboxyl terminal domain of RNA polymerase II, whereas kinetic coupling seems to be linked to how changes in chromatin structure and other factors affect transcription elongation.

  11. Revisiting the solar hydrogen alternative

    SciTech Connect

    Tomkiewicz, M.

    1996-09-01

    Research aimed at the development of technology to advance the solar-hydrogen alternative is per definition mission oriented. The priority that society puts on such research rise and fall with the priorities that we associate with the mission. The mission that we associate with the hydrogen economy is to provide a technological option for an indefinitely sustainable energy and material economies in which society is in equilibrium with its environment. In this paper we try to examine some global aspects of the hydrogen alternative and recommend formulation of a {open_quotes}rational{close_quotes} tax and regulatory system that is based on efforts needed to restore the ecological balance. Such a system, once entered into the price structure of the alternative energy schemes, will be used as a standard to compare energy systems that in turn will serve as a base for prioritization of publicly supported research and development.

  12. Gasohol - Analysis and biomass alternatives

    NASA Astrophysics Data System (ADS)

    1980-11-01

    The economics of fermentation ethanol as a near-term alternative to liquid hydrocarbon fuels are analyzed and alternatives to grain-fermented ethanol are examined. Based on estimates of raw material and production costs and energy consumption, it is shown that net production costs for alcohol fuel from corn amount to $2.14/gallon, with no significant net consumption or gain in energy. It is also pointed out that the use of grain for alcohol production will influence quantities available for livestock production and export, and that land available for grain production is limited. Consideration is then given to the economic potential of using cellulosic biomass from agricultural and forest residues in the production of ethanol fuels and coal gasification for methanol production, and it is pointed out that these alternatives offer economic, energy and oil-savings advantages over ethanol production from grains.

  13. Genetics Home Reference: alternating hemiplegia of childhood

    MedlinePlus

    ... Conditions alternating hemiplegia of childhood alternating hemiplegia of childhood Enable Javascript to view the expand/collapse boxes. ... Open All Close All Description Alternating hemiplegia of childhood is a neurological condition characterized by recurrent episodes ...

  14. Alternative Fuel News, Vol. 6, No. 4

    SciTech Connect

    Not Available

    2003-03-01

    Quarterly magazine with articles on Alternate Fuel Vehicles (AFVs) in India, alternative fuels for emergency preparedness, and testing of propane vehicles by UPS. Also an interview of author Jeremy Rifkin on how alternative fuels provide pathways to hydrogen.

  15. FMDP reactor alternative summary report: Volume 4, Evolutionary LWR alternative

    SciTech Connect

    1996-09-01

    Significant quantities of weapons-usable fissile materials [primarily plutonium and highly enriched uranium (HEU)] have become surplus to national defense needs both in the United States and Russia. These stocks of fissile materials pose significant dangers to national and international security. The dangers exist not only in the potential proliferation of nuclear weapons but also in the potential for environmental, safety, and health (ES&H) consequences if surplus fissile materials are not properly managed. The purpose of this report is to provide schedule, cost, and technical information that will be used to support the Record of Process (ROD). Following the screening process, DOE/MD via its national laboratories initiated a more detailed analysis activity to further evaluate each of the ten plutonium disposition alternatives that survived the screening process. Three ``Alternative Teams,`` chartered by DOE and comprised of technical experts from across the DOE national laboratory complex, conducted these analyses. One team was chartered for each of the major disposition classes (borehole, immobilization, and reactors). During the last year and a half, the Fissile Materials Disposition Program (FMDP) Reactor Alternative Team (RxAT) has conducted extensive analyses of the cost, schedule, technical maturity, S&S, and other characteristics of reactor-based plutonium disposition. The results of the RxAT`s analyses of the existing LWR, CANDU, and partially complete LWR alternatives are documented in Volumes 1-3 of this report. This document (Volume 4) summarizes the results of these analyses for the ELWR-based plutonium disposition option.

  16. Multipebble Simulations for Alternating Automata

    NASA Astrophysics Data System (ADS)

    Clemente, Lorenzo; Mayr, Richard

    We study generalized simulation relations for alternating Büchi automata (ABA), as well as alternating finite automata. Having multiple pebbles allows the Duplicator to "hedge her bets" and delay decisions in the simulation game, thus yielding a coarser simulation relation. We define (k 1,k 2)-simulations, with k 1/k 2 pebbles on the left/right, respectively. This generalizes previous work on ordinary simulation (i.e., (1,1)-simulation) for nondeterministic Büchi automata (NBA)[4] in and ABA in [5], and (1,k)-simulation for NBA in [3].

  17. Two alternative versions of strangeness

    PubMed Central

    Nishijima, Kazuhikoa

    2008-01-01

    The concept of strangeness emerged from the low energy phenomenology before the entry of quarks in particle physics. The connection between strangeness and isospin is rather accidental and loose and we recognize later that the definition of strangeness is model-dependent. Indeed, in Gell-Mann’s triplet quark model we realize that there is a simple alternative representation of strangeness. When the concept of generations is incorporated into the quark model we find that only the second alternative version of strangeness remains meaningful, whereas the original one does no longer keep its significance. PMID:18997448

  18. The neurogenetics of alternative splicing

    PubMed Central

    Vuong, Celine K.; Black, Douglas L.; Zheng, Sika

    2016-01-01

    Alternative precursor-mRNA splicing is a key mechanism for regulating gene expression in mammals and is controlled by specialized RNA-binding proteins. The misregulation of splicing is implicated in multiple neurological disorders. We describe recent mouse genetic studies of alternative splicing that reveal its critical role in both neuronal development and the function of mature neurons. We discuss the challenges in understanding the extensive genetic programmes controlled by proteins that regulate splicing, both during development and in the adult brain. PMID:27094079

  19. Spent-fuel-storage alternatives

    SciTech Connect

    Not Available

    1980-01-01

    The Spent Fuel Storage Alternatives meeting was a technical forum in which 37 experts from 12 states discussed storage alternatives that are available or are under development. The subject matter was divided into the following five areas: techniques for increasing fuel storage density; dry storage of spent fuel; fuel characterization and conditioning; fuel storage operating experience; and storage and transport economics. Nineteen of the 21 papers which were presented at this meeting are included in this Proceedings. These have been abstracted and indexed. (ATT)

  20. Mobile Alternative Fueling Station Locator

    SciTech Connect

    Not Available

    2009-04-01

    The Department of Energy's Alternative Fueling Station Locator is available on-the-go via cell phones, BlackBerrys, or other personal handheld devices. The mobile locator allows users to find the five closest biodiesel, electricity, E85, hydrogen, natural gas, and propane fueling sites using Google technology.

  1. Alternatives to War in History.

    ERIC Educational Resources Information Center

    Kimball, Jeffrey

    1994-01-01

    Asserts that human history is a story of paradoxes: cooperation and conflict, war and peace. States that, throughout history, various individuals and groups have sought alternatives to war. Describes attempts to keep the peace, to manage conflict, and to initiate social reforms that eliminate the causes of war. (CFR)

  2. Alternatives for jet engine control

    NASA Technical Reports Server (NTRS)

    Sain, M. K.

    1984-01-01

    The technical progress of researches Alternatives for Jet Engine Control is reported. A numerical study employing feedback tensors for optimal control of nonlinear systems was completed. It is believed that these studies are the first of their kind. State regulation, with a decrease in control power is demonstrated. A detailed treatment follows.

  3. An Alternative to Thought Suppression?

    ERIC Educational Resources Information Center

    Boice, Robert

    2012-01-01

    Comments on the original article, "Setting free the bears: Escape from thought suppression," by D. M. Wegner (see record 2011-25622-008). While Wegner supposed that we might have to learn to live with bad thoughts, the present author discusses the use of imagination and guided imagery as an alternative to forced thought suppression.

  4. Community College Career Alternatives Handbook.

    ERIC Educational Resources Information Center

    Snider, Patricia A.; Valente, Patricia L.

    This handbook was designed as a resource on career alternatives for counselors and students and to identify the Illinois colleges and universities to which the community college student may transfer to complete his/her education. The handbook is classified by college majors offered at Morton College (MC), and is based on information obtained from…

  5. Alternative Careers in Physical Education.

    ERIC Educational Resources Information Center

    Lambert, Charlotte

    Several alternate definitions of "physical education" can be presented to illustrate the fact that changes in name or definition open the way to new opportunities and new ways of thinking of career options. Traditional definitions of physical education have limited it to a profession of teaching in the traditional school system normal…

  6. Renewable Energy Alternatives in Maryland.

    ERIC Educational Resources Information Center

    Welsh, Greg E.; McClellan, Deborah A. S.

    This handbook discusses the renewable energy resources suitable for use in Maryland. It follows a question and answer format with sections about the following alternative renewable energy sources; solar, wind, wood, water, bio-gas/methane, and geothermal. Each section includes a list of recommended readings, appropriate agencies or organizations,…

  7. A Simple Alternative to Grading

    ERIC Educational Resources Information Center

    Potts, Glenda

    2010-01-01

    In this article, the author investigates whether an alternative grading system (contract grading) would yield the same final grades as traditional grading (letter grading), and whether or not it would be accepted by students. The author states that this study demonstrated that contract grading was widely, and for the most part, enthusiastically…

  8. Looking for alternative energy sources.

    PubMed

    Gross, Michael

    2012-02-21

    With unrest in oil-exporting countries, backlashes against biofuels and photovoltaics, and a nuclear incident in Japan, the year 2011 rattled confidence in future energy supplies. The search for alternatives is all the more urgent, but some of the solutions investigated hark back to fossil fuels that we can't afford to burn.

  9. Not Just Another Alternative School

    ERIC Educational Resources Information Center

    Gulson, Kalervo N.; Webb, P. Taylor

    2016-01-01

    In this article, we problematize the establishment of an Africentric Alternative School in Toronto, Canada. We argue that policy, and race and racializations cannot be understood outside of, or immune to, neoliberalism. We contend that policy is a form of racial biopolitics, and race is now produced through neoliberal markets, in conjunction with…

  10. Alternative Education: The Cutting Edge?

    ERIC Educational Resources Information Center

    Byrne, Jay

    2004-01-01

    Miami Valley Career Technology Youth Connections, an alternative high school located in Dayton, Ohio, has an enrollment of 160 students and was created as a joint venture among local politicians to address the high dropout rates in Montgomery County, Ohio. To achieve this, the Montgomery County commissioners created a task force to develop…

  11. Alternatives for jet engine control

    NASA Technical Reports Server (NTRS)

    Sain, M. K.

    1984-01-01

    The technical progress of researches on alternatives for jet engine control is reported. Extensive numerical testing is included. It is indicated that optimal inputs contribute significantly to the process of calculating tensor approximations for nonlinear systems, and that the resulting approximations may be order-reduced in a systematic way.

  12. Alternatives for jet engine control

    NASA Technical Reports Server (NTRS)

    Sain, M. K.

    1983-01-01

    The technical progress of researches on alternatives for jet engine control, is reported. The principal new activities involved the initial testing of an input design method for choosing the inputs to a non-linear system to aid the approximation of its tensor parameters, and the beginning of order reduction studies designed to remove unnecessary monomials from tensor models.

  13. Alternative Sources of Student Financing.

    ERIC Educational Resources Information Center

    Cross, Dolores E.

    Financial barriers to college attendance that affect women, minorities, low-income, and other nontraditional students are identified, along with alternative sources of student financial aid. Research has suggested that financially-independent students are most vulnerable to fluctuations in aid, and tend to have low incomes, be minority members or…

  14. An Overview of Alternative Education

    ERIC Educational Resources Information Center

    Aron, Laudan Y.

    2006-01-01

    This publication represents the first in a series of papers on alternative education for the U.S. Department of Labor. The main focus of this review is community- or district-based programs that have as their primary focus the re-engagement of out-of-school youth in learning in order to better prepare these youth to successfully enter high growth…

  15. Imaging Alternative Future School Organizations.

    ERIC Educational Resources Information Center

    Popper, Samuel H., Ed.

    This publication presents the proceedings of the University of Minnesota UCEA Career Development Seminar on alternative school organization for the future. Participants addressed themselves to how both universities and public school systems must adapt to changing social aspirations if they are to remain effective. This entails education…

  16. Alternative nitrogen sources for cotton

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Several alternative nitrogen (N) sources, rates of N, and amendments were evaluated at Prattville, Alabama, on cotton in 2008. Nitrogen rates reported are for sidedress application only. Dry urea produced the highest yield, averaging 1100 pounds lint per acre. Ammonia volatilization was measured fr...

  17. Alternatives to Afrocentrism. Second Edition.

    ERIC Educational Resources Information Center

    Miller, John J., Ed.

    The essays in this collection place the current Afrocentric movement in its historical context and offer alternative suggestions about how to teach African American students about their history. The first section deals with the roots of Afrocentrism, analyzes the content of Afrocentric books and curricula, and discusses the impact of Afrocentrism…

  18. Home Schooling: A Controversial Alternative.

    ERIC Educational Resources Information Center

    Duffey, Jane

    1998-01-01

    Home schooling, an alternative involving about 1 million students annually, walks a fine line in an educational reform era. Home-schooling families have succeeded in establishing their constitutional right to educate their children and have proven their educational programs' legitimacy with achievement test results and with successful "graduates."…

  19. Alternatives To Dissection. Second Edition.

    ERIC Educational Resources Information Center

    DeRosa, Bill, Ed.; Winiarskyj, Lesia, Ed.

    This packet attempts to provide educationally sound alternatives to dissection in the classroom, thereby making it possible for teachers to eliminate dissection from the curriculum. This packet can also be used by educators who include dissection in their curricula but consider it important to respect the expression of students' ethical, moral, or…

  20. Alternative Approaches to Introductory Economics.

    ERIC Educational Resources Information Center

    Bonello, Frank J.; And Others

    This document examines the educational output of three alternative approaches to introductory macroeconomics at the University of Notre Dame. The framework for evaluation consists of the cognitive and affective tradeoffs entailed by using a new experimental course as opposed to two more traditional courses. The experimental course is a freshman…

  1. Alternatives to Grading Student Writing.

    ERIC Educational Resources Information Center

    Tchudi, Stephen, Ed.

    The result of an investigation into the grading writing by the National Council of Teachers of English Committee on Alternatives to Grading Student Writing, this collection of essays offers the writing teacher several innovative and interesting options. Following an introduction by the editor (chair of the Committee), in which he delineates the…

  2. An Alternative to Process Recording

    ERIC Educational Resources Information Center

    Baker, Joan; And Others

    1976-01-01

    Some disadvantages in the use of process recordings as an assessment and teaching tool for evaluating the communication skills of the student in nurse-client interactions are discussed. A more useful alternative process requires actual observation and subsequent participation by the instructor during student-client interviews. (EC)

  3. An Alternative Triangle Area Strategy

    ERIC Educational Resources Information Center

    Shockey, T. L.; Zhang, P.; Brosnan, P.

    2016-01-01

    We explore the mathematics engagement of a group of mathematics coaches, working in k-12 mathematics education. The incenter of a triangle is used to derive an alternative formula for the area of a triangle inspired by Usiskin, Peressini, Marhisotto, and Stanley (2002).

  4. Alternative Assignment Incentive Pay Formats

    DTIC Science & Technology

    2005-06-01

    Suite 1204, Arlington, VA 22202-4302, and to the Office of Management and Budget, Paperwork Reduction Project (0704-0188) Washington DC 20503. 1...degree of MASTER OF BUSINESS ADMINISTRATION from the NAVAL POSTGRADAUTE SCHOOL June 2005 Authors... Business and Public Policy iv THIS PAGE INTENTIONALLY LEFT BLANK v ALTERNATIVE

  5. Alternative Routes for Teacher Certification.

    ERIC Educational Resources Information Center

    Education Commission of the States, Denver, CO.

    This publication presents a series of charts, designed for quick reference, which describe the status of alternative teacher certification routes in each of the 50 states. The charts were prepared in response to an increasing number of inquiries from educators, policy makers, and the public. Information was gathered by telephone surveys of state…

  6. 40 CFR 191.26 - Alternative provisions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Alternative provisions. 191.26 Section....26 Alternative provisions. The Administrator may, by rule, substitute for any of the provisions of this subpart alternative provisions chosen after: (a) The alternative provisions have been proposed...

  7. Academic Programs in Alternative Education: An Overview

    ERIC Educational Resources Information Center

    Ruzzi, Betsy Brown; Kraemer, Jacqueline

    2006-01-01

    This paper, second in a series of papers on alternative education, examines the academic programming in alternative education programs by reviewing the literature specifically focused on the academic programs in alternative education and summarizing a survey of fifteen alternative education programs. It suggests options for further research on…

  8. Alternative Medicine and Alzheimer's Disease

    PubMed Central

    Kelley, Brendan J.; Knopman, David S.

    2009-01-01

    Background Alternative medicine has an extensive worldwide history and is commonly used by older patients. A number of different alternative medicines are used by patients having Alzheimer's disease. It is both desirable and expected for clinicians to be acquainted with these medications. Review Summary This paper discusses the available clinical trial evidence regarding eight agents commonly used by people having Alzheimer's disease. We provide an overview of the history and basic scientific evidence available for each agent, followed by a critical analysis of the evidence available from clinical trials, including the number of participants, trial duration and specific outcomes evaluated. Conclusion While many of these compounds have been associated with interesting basic science, none has shown clear clinical benefit to date. Data available for some, such as ginkgo biloba, curcumin and huperzine A, suggest that further evaluation is warranted. Familiarity with this literature will allow clinicians to provide meaningful recommendations to patients who wish to use these agents. PMID:18784599

  9. Wastewater privatization: A beneficial alternative

    SciTech Connect

    Wakeman, R.F.; Drewry, W.A.

    1999-07-01

    Municipalities with wastewater operations face increasing requirements to maximize efficiency, implement capital improvements, and ensure environmental compliance. Privatization is a relatively unused alternative offering benefits in the areas of cost-effective operations, flexible financing, technology access, and compliance assurance. Recent executive direction and tax code changes have opened new doors for mutually beneficial public-private partnerships. Wastewater privatization has historically consisted of short-term contract agreements for treatment operations, but looming infrastructure recapitalization and development requirements have catalyzed an exploration of non-traditional alternatives that include private sector financing, development, and operation of entire wastewater systems, The purpose of this paper is to show why privatization must be considered, evaluate the different levels available, and generate an analytical aid for communities taking their first look at privatization opportunities.

  10. Alternate-fuel reactor studies

    SciTech Connect

    Evans, K. Jr.; Ehst, D.A.; Gohar, Y.; Jung, J.; Mattas, R.F.; Turner, L.R.

    1983-02-01

    A number of studies related to improvements and/or greater understanding of alternate-fueled reactors is presented. These studies cover the areas of non-Maxwellian distributions, materials and lifetime analysis, a /sup 3/He-breeding blanket, tritium-rich startup effects, high field magnet support, and reactor operation spanning the range from full D-T operation to operation with no tritium breeding.

  11. The Economic Evaluation of Alternatives

    DTIC Science & Technology

    2010-02-08

    structuring cost-effectiveness analyses is alternately referred to as Multiple-criteria Decision-making (MCDM), Multi-attribute Utility Theory (MAUT...1992). Multiple criteria decision making, multi-attribute utility theory . Management Science, 38(5), pp645-654. Edwards, W., von Winterfeldt, D...ORGANIZATION NAME (S) AND ADDRESS (ES) NAVAL POSTGRADUATE SCHOOL GRADUATE SCHOOL OF BUSINESS AND PUBLIC POLICY 555 DYER ROAD MONTEREY, CA 93943-5103 8

  12. Alternative therapies in veterinary dermatology.

    PubMed

    Budgin, Jeanne B; Flaherty, Molly J

    2013-01-01

    This article presents an overview of alternative therapies for skin disorders including traditional Chinese medicine (acupuncture and Chinese herbs), homeopathy, and Western herbs and plant extracts. The medical and veterinary literature on the aforementioned modalities will be reviewed with a focus on reduction of inflammation and pruritus of the skin and ear canal in the canine species. Clinical application and potential adverse effects will also be included when available.

  13. Alternative scenarios utilizing nonterrestrial resources

    NASA Technical Reports Server (NTRS)

    Eldred, Charles H.; Roberts, Barney B.

    1992-01-01

    A collection of alternative scenarios that are enabled or substantially enhanced by the utilization of nonterrestrial resources is provided. We take a generalized approach to scenario building so that our report will have value in the context of whatever goals are eventually chosen. Some of the topics covered include the following: lunar materials processing; asteroid mining; lunar resources; construction of a large solar power station; solar dynamic power for the space station; reduced gravity; mission characteristics and options; and tourism.

  14. Ambitious Philippine alternative energy plans

    SciTech Connect

    Not Available

    1981-09-07

    The Philippines is to spend $5.4 billion over the next ten years for the development of alternative sources of energy. These would include the development of fuel woods and other biomass, and the commercialization of a coconut/diesel-oil fuel. It is hoped that the Philippines' dependence on imported oil will be reduced from about 80% today to around 50% by the end of the decade.

  15. Alternative Timing Networks with GPS

    DTIC Science & Technology

    1989-11-01

    receiving stations has been investigated. The xnethods of llsirlg tht: Global P~s i t~ iun- ing System ( GPS ) for transferring time in previolis work has...planes established by the positions of the other stations used to range to six SV’s. Tn this coordinate system the number of observations (24) will...ALTERNATIVE TIMING NETWORKS WITH GPS G.P. Landis, S. Stebbins, and ILL. Heard Naval ltesearch Laboratory Washington, D.C. and H.F. Pliegel The

  16. Alternative to Nitric Acid Passivation

    NASA Technical Reports Server (NTRS)

    Kessel, Kurt R.

    2016-01-01

    Corrosion is an extensive problem that affects the National Aeronautics and Space Administration (NASA) and European Space Agency (ESA). The deleterious effects of corrosion result in steep costs, asset downtime affecting mission readiness, and safety risks to personnel. It is vital to reduce corrosion costs and risks in a sustainable manner. The primary objective of this effort is to qualify citric acid as an environmentally-preferable alternative to nitric acid for passivation of stainless steel alloys.

  17. Alternative Aviation Fuel Experiment (AAFEX)

    NASA Technical Reports Server (NTRS)

    Anderson, B. E.; Beyersdorf, A. J.; Hudgins, C. H.; Plant, J. V.; Thornhill, K. L.; Winstead, E. L.; Ziemba, L. D.; Howard, R.; Corporan, E.; Miake-Lye, R. C.; Herndon, S. C.; Timko, M.; Woods, E.; Dodds, W.; Lee, B.; Santoni, G.; Whitefield, P.; Hagen, D.; Lobo, P.; Knighton, W. B.; Bulzan, D.; Tacina, K.; Wey, C.; VanderWal, R.; Bhargava, A.

    2011-01-01

    The rising cost of oil coupled with the need to reduce pollution and dependence on foreign suppliers has spurred great interest and activity in developing alternative aviation fuels. Although a variety of fuels have been produced that have similar properties to standard Jet A, detailed studies are required to ascertain the exact impacts of the fuels on engine operation and exhaust composition. In response to this need, NASA acquired and burned a variety of alternative aviation fuel mixtures in the Dryden Flight Research Center DC-8 to assess changes in the aircraft s CFM-56 engine performance and emission parameters relative to operation with standard JP-8. This Alternative Aviation Fuel Experiment, or AAFEX, was conducted at NASA Dryden s Aircraft Operations Facility (DAOF) in Palmdale, California, from January 19 to February 3, 2009 and specifically sought to establish fuel matrix effects on: 1) engine and exhaust gas temperatures and compressor speeds; 2) engine and auxiliary power unit (APU) gas phase and particle emissions and characteristics; and 3) volatile aerosol formation in aging exhaust plumes

  18. Thyroid Disease and Complementary and Alternative Medicine (CAM)

    MedlinePlus

    ... Alternative Medicine in Thyroid Disease Complementary and Alternative Medicine in Thyroid Disease (CAM) WHAT IS COMPLEMENTARY AND ALTERNATIVE MEDICINE (CAM)? Complementary and Alternative Medicine (CAM) is defined ...

  19. FMDP reactor alternative summary report. Volume 1 - existing LWR alternative

    SciTech Connect

    Greene, S.R.; Bevard, B.B.

    1996-10-07

    Significant quantities of weapons-usable fissile materials [primarily plutonium and highly enriched uranium (HEU)] are becoming surplus to national defense needs in both the United States and Russia. These stocks of fissile materials pose significant dangers to national and international security. The dangers exist not only in the potential proliferation of nuclear weapons but also in the potential for environmental, safety, and health (ES&H) consequences if surplus fissile materials are not properly managed. This document summarizes the results of analysis concerned with existing light water reactor plutonium disposition alternatives.

  20. [Alternative medicine: really an alternative to academic medicine?].

    PubMed

    Happle, R

    2000-06-01

    Numerous courses on alternative medicine are regularly advertised in Deutsches Arzteblatt, the organ of the German Medical Association. The present German legislation likewise supports this form of medicine, and this explains why Iscador, an extract of the mistletoe, is found in the Rote Liste, a directory of commercially available medical drugs, under the heading "cytostatic and antimetastatic drugs" although such beneficial effect is unproven. To give another example, a German health insurance fund was sentenced to pay for acupuncture as a treatment for hepatic failure. This judgement is characteristic of the present German judicial system and represents a victory of "oracling irrationalism" (Popper). The astonishing popularity of alternative medicine can be explained by a revival of romanticism. An intellectually fair opposite position has been delineated by Karl Popper in the form of critical rationalism. It is important to realize, however, that our decision to adhere to rational thinking is made in the innermost depth of our heart but not on the basis of rational arguing. Rather, the decision in favor of reason has a moral dimension.

  1. Thermoelectric converters for alternating current standards

    NASA Astrophysics Data System (ADS)

    Anatychuk, L. I.; Taschuk, D. D.

    2012-06-01

    Thermoelectric converters of alternating current remain priority instruments when creating standard equipment. This work presents the results of design and manufacture of alternating current converter for a military standard of alternating current in Ukraine. Results of simulation of temperature distribution in converter elements, ways of optimization to improve the accuracy of alternating current signal reproduction are presented. Results of metrological trials are given. The quality of thermoelectric material specially created for alternating current metrology is verified. The converter was used in alternating current standard for the frequency range from 10 Hz to 30 MHz. The efficiency of using thermoelectric signal converters in measuring instruments is confirmed.

  2. Alternative approaches to epilepsy treatment.

    PubMed

    McElroy-Cox, Caitlin

    2009-07-01

    Complementary and alternative medicine (CAM) is a diverse group of health care practices and products that fall outside the realm of traditional Western medical theory and practice and that are used to complement or replace conventional medical therapies. The use of CAM has increased over the past two decades, and surveys have shown that up to 44% of patients with epilepsy are using some form of CAM treatment. This article reviews the CAM modalities of meditation, yoga, relaxation techniques, biofeedback, nutritional and herbal supplements, dietary measures, chiropractic care, acupuncture, Reiki, and homeopathy and what is known about their potential efficacy in patients with epilepsy.

  3. Bayesian Alternation during Tactile Augmentation

    PubMed Central

    Goeke, Caspar M.; Planera, Serena; Finger, Holger; König, Peter

    2016-01-01

    A large number of studies suggest that the integration of multisensory signals by humans is well-described by Bayesian principles. However, there are very few reports about cue combination between a native and an augmented sense. In particular, we asked the question whether adult participants are able to integrate an augmented sensory cue with existing native sensory information. Hence for the purpose of this study, we build a tactile augmentation device. Consequently, we compared different hypotheses of how untrained adult participants combine information from a native and an augmented sense. In a two-interval forced choice (2 IFC) task, while subjects were blindfolded and seated on a rotating platform, our sensory augmentation device translated information on whole body yaw rotation to tactile stimulation. Three conditions were realized: tactile stimulation only (augmented condition), rotation only (native condition), and both augmented and native information (bimodal condition). Participants had to choose one out of two consecutive rotations with higher angular rotation. For the analysis, we fitted the participants' responses with a probit model and calculated the just notable difference (JND). Then, we compared several models for predicting bimodal from unimodal responses. An objective Bayesian alternation model yielded a better prediction (χred2 = 1.67) than the Bayesian integration model (χred2 = 4.34). Slightly higher accuracy showed a non-Bayesian winner takes all (WTA) model (χred2 = 1.64), which either used only native or only augmented values per subject for prediction. However, the performance of the Bayesian alternation model could be substantially improved (χred2 = 1.09) utilizing subjective weights obtained by a questionnaire. As a result, the subjective Bayesian alternation model predicted bimodal performance most accurately among all tested models. These results suggest that information from augmented and existing sensory modalities in

  4. Machine translation project alternatives analysis

    NASA Technical Reports Server (NTRS)

    Bajis, Catherine J.; Bedford, Denise A. D.

    1993-01-01

    The Machine Translation Project consists of several components, two of which, the Project Plan and the Requirements Analysis, have already been delivered. The Project Plan details the overall rationale, objectives and time-table for the project as a whole. The Requirements Analysis compares a number of available machine translation systems, their capabilities, possible configurations, and costs. The Alternatives Analysis has resulted in a number of conclusions and recommendations to the NASA STI program concerning the acquisition of specific MT systems and related hardware and software.

  5. ALTERNATIVE APPROACH TO ESTIMATING CANCER ...

    EPA Pesticide Factsheets

    The alternative approach for estimating cancer potency from inhalation exposure to asbestos seeks to improve the methods developed by USEPA (1986). This efforts seeks to modify the the current approach for estimating cancer potency for lung cancer and mesothelioma to account for the current scientific consensus that cancer risk from asbestos depends both on mineral type and on particle size distribution. In brief, epidemiological exposure-response data for lung cancer and mesothelioma in asbestos workers are combined with estimates of the mineral type(s) and partical size distribution at each exposure location in order to estimate potency factors that are specific to a selected set of mineral type and size

  6. Alternate nozzle ablative materials program

    NASA Technical Reports Server (NTRS)

    Kimmel, N. A.

    1984-01-01

    Four subscale solid rocket motor tests were conducted successfully to evaluate alternate nozzle liner, insulation, and exit cone structural overwrap components for possible application to the Space Shuttle Solid Rocket Motor (SRM) nozzle asasembly. The 10,000 lb propellant motor tests were simulated, as close as practical, the configuration and operational environment of the full scale SRM. Fifteen PAN based and three pitch based materials had no filler in the phenolic resin, four PAN based materials had carbon microballoons in the resin, and the rest of the materials had carbon powder in the resin. Three nozzle insulation materials were evaluated; an aluminum oxide silicon oxide ceramic fiber mat phenolic material with no resin filler and two E-glass fiber mat phenolic materials with no resin filler. It was concluded by MTI/WD (the fabricator and evaluator of the test nozzles) and NASA-MSFC that it was possible to design an alternate material full scale SRM nozzle assembly, which could provide an estimated 360 lb increased payload capability for Space Shuttle launches over that obtainable with the current qualified SRM design.

  7. Mitigation alternatives for L Lake

    SciTech Connect

    Moore, D.B.

    1988-11-03

    The current condition of L Lake/Steel Creek was summarized in a report to SCDHEC in June 1988 which reported that the L Lake and Steel Creek ecosystems were adequately developing towards balanced biological communities. If mitigation for L Lake inputs, specifically temperature and nutrients, are required, several viable alternatives are available. A report prepared by Spencer in 1986 discusses the various options available for cooling L-Reactor discharges. In effect, a small cooling tower is the only realistic solution to reducing effluent temperatures. Nutrient mitigation can take several approaches including upstream sewage treatment, hypolimnetic withdrawal, dilution of input water by Par Pond water, precipitation of nutrients, and sediment oxidation. None of these systems would influence the thermal regime, but would significantly reduce nutrient input into the system. One beneficial use of L-Lake thermal effluents is algaculture, the production of useful algae. A document prepared in 1988 concludes that algaculture is a technically and economically feasible mitigation alternative for L Lake and could allow L Lake to be handled under Section 318 of the Clean Water Act.

  8. Alternate Energy for National Security.

    NASA Astrophysics Data System (ADS)

    Rath, Bhakta

    2010-02-01

    Recent price fluctuations at the gas pump have brought our attention to the phenomenal increase of global energy consumption in recent years. It is now evident that we have almost reached a peak in global oil production. Several projections indicate that total world consumption of oil will rise by nearly 60 per cent between 1999 and 2020. In 1999 consumption was equivalent to 86 million barrels of oil per day, which has reached a peak of production extracted from most known oil reserves. These projections, if accurate, will present an unprecedented crisis to the global economy and industry. As an example, in the US, nearly 40 per cent of energy usage is provided by petroleum, of which nearly a third is used in transportation. The US Department of Defense (DOD) is the single largest buyer of fuel, amounting to, on the average, 13 million gallons per day. Additionally, these fuels have to meet different requirements that prevent use of ethanol additives and biodiesel. An aggressive search for alternate energy sources, both renewable and nonrenewable, is vital. The presentation will review national and DOD perspectives on the exploration of alternate energy with a focus on energy derivable from the ocean. )

  9. Alternative therapies for postmenopausal women.

    PubMed

    Speroff, Leon

    2005-01-01

    Alternative therapies are being used by postmenopausal women in attempts to treat all of the complaints and medical conditions of the menopause. One-fifth of those who take prescription drugs for these indications also take herbal remedies and/or high-dose vitamins, most often without disclosing the fact to the physician. Although studies of alternative therapies are short-term and rarely focused on safety--let alone efficacy--in the long-term, there are many studies spread over the large number of substances involved. More than 130 studies, including meta-analyses, are reviewed in this article under the headings of phytoestrogens, especially from soy; therapies for hot flushes; and preventives for cardiovascular disease, osteoporosis, and breast cancer. Special attention is given to the recently recognized daidzein metabolite equol, and for the sake of completeness there are reviews of the unconventional, but not botanical, treatments estriol, transdermal progesterone, and dehydroepiandrosterone. The total picture produced by conscientious review of the studies is bleak overall, but there seems to be good reason to pursue the possibilities inherent in soy protein with phytoestrogens in populations of women who endogenously produce equol.

  10. Alternative forms for genomic clines

    PubMed Central

    Fitzpatrick, Benjamin M

    2013-01-01

    Understanding factors regulating hybrid fitness and gene exchange is a major research challenge for evolutionary biology. Genomic cline analysis has been used to evaluate alternative patterns of introgression, but only two models have been used widely and the approach has generally lacked a hypothesis testing framework for distinguishing effects of selection and drift. I propose two alternative cline models, implement multivariate outlier detection to identify markers associated with hybrid fitness, and simulate hybrid zone dynamics to evaluate the signatures of different modes of selection. Analysis of simulated data shows that previous approaches are prone to false positives (multinomial regression) or relatively insensitive to outlier loci affected by selection (Barton's concordance). The new, theory-based logit-logistic cline model is generally best at detecting loci affecting hybrid fitness. Although some generalizations can be made about different modes of selection, there is no one-to-one correspondence between pattern and process. These new methods will enhance our ability to extract important information about the genetics of reproductive isolation and hybrid fitness. However, much remains to be done to relate statistical patterns to particular evolutionary processes. The methods described here are implemented in a freely available package “HIest” for the R statistical software (CRAN; http://cran.r-project.org/). PMID:23919142

  11. 7 CFR 981.35 - Alternates.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE ALMONDS GROWN IN CALIFORNIA Order Regulating Handling Almond Board of California § 981.35 Alternates. An alternate for a member for the...

  12. 7 CFR 981.35 - Alternates.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE ALMONDS GROWN IN CALIFORNIA Order Regulating Handling Almond Board of California § 981.35 Alternates. An alternate for a member for the...

  13. 7 CFR 981.35 - Alternates.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE ALMONDS GROWN IN CALIFORNIA Order Regulating Handling Almond Board of California § 981.35 Alternates. An alternate for a member for the...

  14. 7 CFR 981.35 - Alternates.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE ALMONDS GROWN IN CALIFORNIA Order Regulating Handling Almond Board of California § 981.35 Alternates. An alternate for a member for the...

  15. 7 CFR 981.35 - Alternates.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE ALMONDS GROWN IN CALIFORNIA Order Regulating Handling Almond Board of California § 981.35 Alternates. An alternate for a member for the...

  16. 7 CFR 906.27 - Alternate members.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... RIO GRANDE VALLEY IN TEXAS Order Regulating Handling Committee § 906.27 Alternate members. An... of the death, removal, resignation, or disqualification of a member, his alternate shall act for...

  17. 7 CFR 906.27 - Alternate members.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... RIO GRANDE VALLEY IN TEXAS Order Regulating Handling Committee § 906.27 Alternate members. An... of the death, removal, resignation, or disqualification of a member, his alternate shall act for...

  18. 7 CFR 906.27 - Alternate members.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... RIO GRANDE VALLEY IN TEXAS Order Regulating Handling Committee § 906.27 Alternate members. An... of the death, removal, resignation, or disqualification of a member, his alternate shall act for...

  19. 7 CFR 906.27 - Alternate members.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... RIO GRANDE VALLEY IN TEXAS Order Regulating Handling Committee § 906.27 Alternate members. An... of the death, removal, resignation, or disqualification of a member, his alternate shall act for...

  20. LIFE CYCLE ASSESSMENT OF ELECTRICITY GENERATION ALTERNATIVES

    EPA Science Inventory

    This presentation summarizes various electricity and electricity/steam cogeneration alternatives. Among these alternatives, are fossil fuel and biomass power generation plants. These plants have different designs due to the need in fossil fuel (coal) plants to include process u...

  1. Complementary and Alternative Medicine for Patients

    MedlinePlus

    ... Ask about Your Treatment Research Complementary and Alternative Medicine for Patients Complementary and alternative medicine (CAM) is ... based on scientific evidence from research studies. Complementary medicine refers to treatments that are used with standard ...

  2. 33 CFR 127.017 - Alternatives.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... written request for the alternative at least 30 days before facility operations under the alternative... same degree of safety provided by the regulations in this part. (b) The COTP approves or...

  3. 33 CFR 127.017 - Alternatives.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... written request for the alternative at least 30 days before facility operations under the alternative... same degree of safety provided by the regulations in this part. (b) The COTP approves or...

  4. 7 CFR 1208.44 - Alternate members.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE PROCESSED RASPBERRY PROMOTION, RESEARCH, AND INFORMATION ORDER Processed Raspberry Promotion, Research, and Information Order National Processed Raspberry Council § 1208.44 Alternate members. An alternate member of the Council, during...

  5. 7 CFR 1208.44 - Alternate members.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE PROCESSED RASPBERRY PROMOTION, RESEARCH, AND INFORMATION ORDER Processed Raspberry Promotion, Research, and Information Order National Processed Raspberry Council § 1208.44 Alternate members. An alternate member of the Council, during...

  6. 7 CFR 932.30 - Alternates.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE OLIVES GROWN IN CALIFORNIA Order Regulating Handling Olive Administrative Committee § 932.30 Alternates. An alternate for a member of...

  7. 7 CFR 932.30 - Alternates.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE OLIVES GROWN IN CALIFORNIA Order Regulating Handling Olive Administrative Committee § 932.30 Alternates. An alternate for a member of...

  8. 7 CFR 932.30 - Alternates.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE OLIVES GROWN IN CALIFORNIA Order Regulating Handling Olive Administrative Committee § 932.30 Alternates. An alternate for a member of...

  9. 7 CFR 932.30 - Alternates.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE OLIVES GROWN IN CALIFORNIA Order Regulating Handling Olive Administrative Committee § 932.30 Alternates. An alternate for a member of...

  10. 7 CFR 932.30 - Alternates.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE OLIVES GROWN IN CALIFORNIA Order Regulating Handling Olive Administrative Committee § 932.30 Alternates. An alternate for a member of...

  11. Advanced Technology and Alternative Fuel Vehicles

    SciTech Connect

    Tuttle, J.

    2001-08-20

    This fact sheet provides a basic overview of today's alternative fuel choices--including biofuels, biodiesel, electricity, and hydrogen--alternative fuel vehicles, and advanced vehicle technology, such as hybrid electric vehicles, fuel cells and advanced drive trains.

  12. 7 CFR 982.36 - Alternates.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE HAZELNUTS GROWN IN OREGON AND WASHINGTON Order Regulating Handling Hazelnut Control Board § 982.36 Alternates. An alternate for a member...

  13. 7 CFR 982.36 - Alternates.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE HAZELNUTS GROWN IN OREGON AND WASHINGTON Order Regulating Handling Hazelnut Control Board § 982.36 Alternates. An alternate for a member...

  14. 7 CFR 982.36 - Alternates.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE HAZELNUTS GROWN IN OREGON AND WASHINGTON Order Regulating Handling Hazelnut Control Board § 982.36 Alternates. An alternate for a member...

  15. 7 CFR 982.36 - Alternates.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE HAZELNUTS GROWN IN OREGON AND WASHINGTON Order Regulating Handling Hazelnut Control Board § 982.36 Alternates. An alternate for a member...

  16. 7 CFR 982.36 - Alternates.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE HAZELNUTS GROWN IN OREGON AND WASHINGTON Order Regulating Handling Hazelnut Control Board § 982.36 Alternates. An alternate for a member...

  17. Are There Feasible Alternatives to Laboratory Animals?

    ERIC Educational Resources Information Center

    Rowan, A. N.

    1976-01-01

    Discusses several alternatives to the use of laboratory animals in investigating biomedical problems. Alternatives include tissue culture, use of plant and bacterial material, redesigning experiments, and construction of mathematical and computer models. (CS)

  18. Resurgence and alternative-reinforcer magnitude.

    PubMed

    Craig, Andrew R; Browning, Kaitlyn O; Nall, Rusty W; Marshall, Ciara M; Shahan, Timothy A

    2017-03-01

    Resurgence is defined as an increase in the frequency of a previously reinforced target response when an alternative source of reinforcement is suspended. Despite an extensive body of research examining factors that affect resurgence, the effects of alternative-reinforcer magnitude have not been examined. Thus, the present experiments aimed to fill this gap in the literature. In Experiment 1, rats pressed levers for single-pellet reinforcers during Phase 1. In Phase 2, target-lever pressing was extinguished, and alternative-lever pressing produced either five-pellet, one-pellet, or no alternative reinforcement. In Phase 3, alternative reinforcement was suspended to test for resurgence. Five-pellet alternative reinforcement produced faster elimination and greater resurgence of target-lever pressing than one-pellet alternative reinforcement. In Experiment 2, effects of decreasing alternative-reinforcer magnitude on resurgence were examined. Rats pressed levers and pulled chains for six-pellet reinforcers during Phases 1 and 2, respectively. In Phase 3, alternative reinforcement was decreased to three pellets for one group, one pellet for a second group, and suspended altogether for a third group. Shifting from six-pellet to one-pellet alternative reinforcement produced as much resurgence as suspending alternative reinforcement altogether, while shifting from six pellets to three pellets did not produce resurgence. These results suggest that alternative-reinforcer magnitude has effects on elimination and resurgence of target behavior that are similar to those of alternative-reinforcer rate. Thus, both suppression of target behavior during alternative reinforcement and resurgence when conditions of alternative reinforcement are altered may be related to variables that affect the value of the alternative-reinforcement source.

  19. Alternative Metal Hot Cutting Operations for Opacity

    DTIC Science & Technology

    2014-10-01

    Distribution A: Approved for public release; distribution is unlimited. TDS-NAVFAC-EXWC-EV-1509 October 2014 Alternative Metal Hot Cutting...demonstration (see Figure 1) and validation. Figure 1: Demonstration of alternative gasified hot - cutting fuel. PROPOSED BENEFITS 1...1205, March 2012. Alternative Metal Hot Cutting Operations for Opacity, TR-NAVFAC-EXWC-EV-1409, November 2014. POINTS OF CONTACT To acquire

  20. Alternative Materials in Libraries: A Handbook.

    ERIC Educational Resources Information Center

    Shore, Elliott, Ed.; Danky, James, Ed.

    The papers presented focus on the library acquisition, processing, and use of alternative publications, which include small press and other materials produced by non-standard, non-establishment groups or individuals. In "Libraries and Alternatives: An Essay," Patricia Glass Schuman discusses the importance of alternative publications and…

  1. Amending pine bark with alternative substrates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Due to a number of factors, pine bark supplies have significantly decreased over the past few years. While alternative substrates are being evaluated, many growers are asking if these alternative substrates can be used to stretch existing PB supplies. In this study, two alternative substrates, “Cl...

  2. Issues in Alternative Assessment: The Japanese Perspective.

    ERIC Educational Resources Information Center

    Butler, Priscilla, Ed.

    A collection of essays addresses issues in alternative assessment in English as-a-Second-Language (ESL) instruction. Chapter 1, "Toward a Definition of Alternative Assessment," (Priscilla Butler) gives an overview of the concept of alternative assessment and introduces some theoretical considerations. Chapter 2, "The Roots of…

  3. First passage failure: Analysis alternatives

    SciTech Connect

    PAEZ,THOMAS L.; NGUYEN,H.P.; WIRSCHING,PAUL H.

    2000-04-17

    Most mechanical and structural failures can be formulated as first passage problems. The traditional approach to first passage analysis models barrier crossings as Poisson events. The crossing rate is established and used in the Poisson framework to approximate the no-crossing probability. While this approach is accurate in a number of situations, it is desirable to develop analysis alternatives for those situations where traditional analysis is less accurate and situations where it is difficult to estimate parameters of the traditional approach. This paper develops an efficient simulation approach to first passage failure analysis. It is based on simulation of segments of complex random processes with the Karhunen-Loeve expansion, use of these simulations to estimate the parameters of a Markov chain, and use of the Markov chain to estimate the probability of first passage failure. Some numerical examples are presented.

  4. Basic sciences: an alternative career?

    PubMed

    Khatri, R

    2013-01-01

    Career selection is a crucial and a complex process which is also true for the medical profession. In the context of our country, due to the limited opportunity and proper guidance, migration of medical graduates to foreign countries is increasing. Though, clinical subjects have a huge attraction, basic science field has failed to impress our medical graduates. In current scenario, basic science field seems to be a dumping site for the incompetent as the candidates who have failed trying their luck elsewhere stumble upon basic science careers though it is not true for all. Moreover, a very few medical graduates are interested in developing their career as a basic scientist. Therefore, to motivate today's young medical graduates, there is a need of a good mentor along with a proper career guidance which can help them to understand the basic science field as an alternative career.

  5. Promoter usage and alternative splicing.

    PubMed

    Kornblihtt, Alberto R

    2005-06-01

    Recent findings justify a renewed interest in alternative splicing (AS): the process is more a rule than an exception as it affects the expression of 60% of human genes; it explains how a vast mammalian proteomic complexity is achieved with a limited number of genes; and mutations in AS regulatory sequences are a widespread source of human disease. AS regulation not only depends on the interaction of splicing factors with their target sequences in the pre-mRNA but is coupled to transcription. A clearer picture is emerging of the mechanisms by which transcription affects AS through promoter identity and occupation. These mechanisms involve the recruitment of factors with dual functions in transcription and splicing (i.e. that contain both functional domains and hence link the two processes) and the control of RNA polymerase II elongation.

  6. Alternative fuels for cancer cells.

    PubMed

    Keenan, Melissa M; Chi, Jen-Tsan

    2015-01-01

    Tumor metabolism is significantly altered to support the various metabolic needs of tumor cells. The most prominent change is the increased tumor glycolysis that leads to increased glucose uptake and utilization. However, it has become obvious that many non-glucose nutrients, such as amino acids, lactate, acetate, and macromolecules, can serve as alternative fuels for cancer cells. This knowledge reveals an unexpected flexibility and evolutionarily conserved model in which cancer cells uptake nutrients from their external environment to fulfill their necessary energetic needs. Tumor cells may have evolved the ability to utilize different carbon sources because of the limited supply of nutrients in their microenvironment, which can be driven by oncogenic mutations or tumor microenvironmental stresses. In certain cases, these factors permanently alter the tumor cells' metabolism, causing certain nutrients to become indispensable and thus creating opportunities for therapeutic intervention to eradicate tumors by their metabolic vulnerabilities.

  7. Alternative approaches to plasma confinement

    NASA Technical Reports Server (NTRS)

    Roth, J. R.

    1978-01-01

    The paper discusses 20 plasma confinement schemes each representing an alternative to the tokamak fusion reactor. Attention is given to: (1) tokamak-like devices (TORMAC, Topolotron, and the Extrap concept), (2) stellarator-like devices (Torsatron and twisted-coil stellarators), (3) mirror machines (Astron and reversed-field devices, the 2XII B experiment, laser-heated solenoids, the LITE experiment, the Kaktus-Surmac concept), (4) bumpy tori (hot electron bumpy torus, toroidal minimum-B configurations), (5) electrostatically assisted confinement (electrostatically stuffed cusps and mirrors, electrostatically assisted toroidal confinement), (6) the Migma concept, and (7) wall-confined plasmas. The plasma parameters of the devices are presented and the advantages and disadvantages of each are listed.

  8. Recent advances in alternative therapies.

    PubMed

    Ziment, I

    2000-01-01

    Complementary and alternative medicine (CAM) is becoming more popular, and CAM remedies are used instead of, or integrated with, orthodox allopathic therapies by many patients with asthma. Although most CAM remedies may have no discernible effects when analyzed by conventional medical techniques, some double-blind controlled studies do suggest that a meaningful benefit can be obtained with acupunture and homeopathic management in asthma. Herbal medicine is more popular, despite little evidence that the vast majority of herbs for asthma have any useful effects other than a nonspecific expectorant action. Dietary adjustment may benefit a small percentage of patients with asthma, but extreme measures are very rarely indicated. Formal pyschologic approaches can help some patients by reducing anxiety. Although most CAM approaches are harmless, the lack of benefit of many remedies and the potential harm from some of them must be recognized.

  9. Alternator control for battery charging

    DOEpatents

    Brunstetter, Craig A.; Jaye, John R.; Tallarek, Glen E.; Adams, Joseph B.

    2015-07-14

    In accordance with an aspect of the present disclosure, an electrical system for an automotive vehicle has an electrical generating machine and a battery. A set point voltage, which sets an output voltage of the electrical generating machine, is set by an electronic control unit (ECU). The ECU selects one of a plurality of control modes for controlling the alternator based on an operating state of the vehicle as determined from vehicle operating parameters. The ECU selects a range for the set point voltage based on the selected control mode and then sets the set point voltage within the range based on feedback parameters for that control mode. In an aspect, the control modes include a trickle charge mode and battery charge current is the feedback parameter and the ECU controls the set point voltage within the range to maintain a predetermined battery charge current.

  10. [Alternative oxidase - never ending story].

    PubMed

    Szal, Bożena; Rychter, Anna M

    2016-01-01

    Investigations of plant cyanide resistant respiration lead to the discovery in mitochondrial respiratory chain of the second terminal oxidase, alternative oxidase (AOX). AOX transfers electrons from reduced ubiquinone to oxygen omitting two coupling places thus lowering energetic efficiency of respiration. The presence of AOX was shown in all plants and also in some fungi, mollusca and protista. In termogenic plants the activity of AOX is connected with heat production. In other organisms AOX activity is important for maintaining metabolic homeostasis (carbon metabolism, cell redox state and energy demand) and ROS homeostasis. In this article structure of plant AOX protein and the regulation on molecular levels was described. Possible role of AOX as stress marker was pointed and the possibility of using AOX in human gene therapy was discussed.

  11. Health management education: current alternatives.

    PubMed

    Weil, Thomas P

    2014-01-01

    The past several decades have witnessed a significant increase in the number of graduate programs in health management, either on campus or online. The alternative for a health professional to attending a graduate program on campus is to receive an MBA or MHA degree online. The current cost ranges from $13,600 to $78,000, with the more expensive online programs tied to graduate programs that are accredited by the Commission on the Accreditation of Healthcare Management Education and provide the names and qualifications of their faculty. The for-profit online programs have not been forthcoming to this author concerning their health management faculty or their curriculum. For the individual desiring more health management education who is unable to enroll, for family or financial reasons, in an on-campus program, the top-tier online programs seem like a worthwhile but is a relatively expensive option.

  12. An alternative to Zoe's Law.

    PubMed

    Dalmau, James

    2015-03-01

    Under the criminal law of New South Wales, the destruction of a foetus (other than in the course of a medical procedure) constitutes grievous bodily harm to the pregnant woman. Charges can be laid for offences against the woman, but not against the foetus. Many are dissatisfied with this. The Crimes Amendment (Zoe's Law) Bill 2013 (No 2) (NSW) aimed to change this by providing that a foetus is taken to be a living person for the purposes of certain offences. The Bill was strongly opposed on the basis that according personhood to a foetus in this way will have undesirable consequences that could erode the reproductive rights of women. The public debate over how the criminal law addresses the destruction of a foetus has centred on Zoe's Law. This article proposes an alternative amendment. that aims, to accommodate the concerns of the Bill's supporters and its detractors.

  13. Alternative Crops and Biofuel Production

    SciTech Connect

    Kenkel, Philip; Holcomb, Rodney B.

    2013-03-01

    In order for the biofuel industry to meet the RFS benchmarks for biofuels, new feedstock sources and production systems will have to be identified and evaluated. The Southern Plains has the potential to produce over a billion gallons of biofuels from regionally produced alternative crops, agricultural residues, and animal fats. While information on biofuel conversion processes is available, it is difficult for entrepreneurs, community planners and other interested individuals to determine the feasibility of biofuel processes or to match production alternatives with feed stock availability and community infrastructure. This project facilitates the development of biofuel production from these regionally available feed stocks. Project activities are concentrated in five major areas. The first component focused on demonstrating the supply of biofuel feedstocks. This involves modeling the yield and cost of production of dedicated energy crops at the county level. In 1991 the DOE selected switchgrass as a renewable source to produce transportation fuel after extensive evaluations of many plant species in multiple location (Caddel et al,. 2010). However, data on the yield and cost of production of switchgrass are limited. This deficiency in demonstrating the supply of biofuel feedstocks was addressed by modeling the potential supply and geographic variability of switchgrass yields based on relationship of available switchgrass yields to the yields of other forage crops. This model made it possible to create a database of projected switchgrass yields for five different soil types at the county level. A major advantage of this methodology is that the supply projections can be easily updated as improved varieties of switchgrass are developed and additional yield data becomes available. The modeling techniques are illustrated using the geographic area of Oklahoma. A summary of the regional supply is then provided.

  14. Alternative calcination development status report

    SciTech Connect

    Boardman, R.D.

    1997-12-01

    The Programmatic Spent Nuclear Fuel and (INEEL) Environmental Restoration and Waste Management Programs Environmental Impact Statement Record of Decision, dated June 1, 1995, specifies that high-level waste stored in the underground tanks at the ICPP continue to be calcined while other options to treat the waste are studied. Therefore, the High-Level Waste Program has funded a program to develop new flowsheets to increase the liquid waste processing rate. Simultaneously, a radionuclide separation process, as well as other options, are also being developed, which will be compared to the calcination treatment option. Two alternatives emerged as viable candidates; (1) elevated temperature calcination (also referred to as high temperature calcination), and (2) sugar-additive calcination. Both alternatives were determined to be viable through testing performed in a lab-scale calcination mockup. Subsequently, 10-cm Calciner Pilot Plant scoping tests were successfully completed for both flowsheets. The results were compared to the standard 500 C, high-ANN flow sheet (baseline flowsheet). The product and effluent streams were characterized to help elucidate the process chemistry and to investigate potential environmental permitting issues. Several supplementary tests were conducted to gain a better understanding of fine-particles generation, calcine hydration, scrub foaming, feed makeup procedures, sugar/organic elimination, and safety-related issues. Many of the experiments are only considered to be scoping tests, and follow-up experiments will be required to establish a more definitive understanding of the flowsheets. However, the combined results support the general conclusion that flowsheet improvements for the NWCF are technically viable.

  15. Expression of alternative oxidase in tomato

    SciTech Connect

    Kakefuda, M.; McIntosh, L. )

    1990-05-01

    Tomato fruit ripening is characterized by an increase in ethylene biosynthesis, a burst in respiration (i.e. the climacteric), fruit softening and pigmentation. As whole tomatoes ripened from mature green to red, there was an increase in the alternative oxidase capacity. Aging pink tomato slices for 24 and 48 hrs also showed an increase of alternative oxidase and cytochrome oxidase capacities. Monoclonal antibodies prepared to the Sauromatum guttatum alternative oxidase were used to follow the appearance of alternative oxidase in tomato fruits. There is a corresponding increase in a 36kDa protein with an increase in alternative oxidase capacity. Effects of ethylene and norbornadiene on alternative oxidase capacity were also studied. We are using an alternative oxidase cDNA clone from potato to study the expression of mRNA in ripening and wounded tomatoes to determine if the gene is transcriptionally regulated.

  16. BIO: an alternative to RIO

    NASA Astrophysics Data System (ADS)

    Okuroglu, Bahri; Oktug, Sema

    2001-07-01

    RED (Random Early Detection) is the most popular active queue management algorithm, although it has some weaknesses. Recently, another active queue management algorithm, BLUE, was proposed and shown that it is more successful in controlling the queue length when high number of flows are active on ECN (Explicit Congestion Notification) capable networks. In this paper, RED and BLUE algorithms are evaluated for different levels of RTTs, with/without ECN support. It is shown that BLUE on ECN incapable networks is not as successful as on ECN capable networks. Differentiated Services architecture suggests that RIO (Red with In and Out) style queue management algorithms are to be used on each AF (Assured Forwarding) queue to offer different levels of services for different priorities at each AF class. Inspired of BLUE's success over RED on ECN capable networks, we developed a simple alternative to RIO, BIO (BLUE with In and Out). BIO, which runs two different BLUE algorithms for in and out packets, was expected to achieve lower loss rates while maximizing link utilization for high number of active flows on AF queues. However, due to the self-configuring architecture of the algorithm, it is observed that BIO marks packets too aggressively and degrades utilization. In this paper, the properties of BIO are also explained and the results obtained are justified.

  17. Boom Rendezvous Alternative Docking Approach

    NASA Technical Reports Server (NTRS)

    Bonometti, Joseph A.

    2006-01-01

    Space rendezvous and docking has always been attempted with primarily one philosophic methodology. The slow matching of one vehicle's orbit by a second vehicle and then a final closing sequence that ends in matching the orbits with perfect precision and with near zero relative velocities. The task is time consuming, propellant intensive, risk inherent (plume impingement, collisions, fuel depletion, etc.) and requires substantial hardware mass. The historical background and rationale as to why this approach is used is discussed in terms of the path-not-taken and in light of an alternate methodology. Rendezvous and docking by boom extension is suggested to have inherent advantages that today s technology can readily exploit. Extension from the primary spacecraft, beyond its inherent large inertia, allows low inertia connections to be made rapidly and safely. Plume contamination issues are eliminated as well as the extra propellant mass and risk required for the final thruster (docking) operations. Space vehicle connection hardware can be significantly lightened. Also, docking sensors and controls require less fidelity; allowing them to be more robust and less sensitive. It is the potential safety advantage and mission risk reduction that makes this approach attractive, besides the prospect of nominal time and mass savings.

  18. Alternative Water Processor Test Development

    NASA Technical Reports Server (NTRS)

    Pickering, Karen D.; Mitchell, Julie L.; Adam, Niklas M.; Barta, Daniel; Meyer, Caitlin E.; Pensinger, Stuart; Vega, Leticia M.; Callahan, Michael R.; Flynn, Michael; Wheeler, Ray; Birmele, Michele; Lunn, Griffin; Jackson, Andrew

    2013-01-01

    The Next Generation Life Support Project is developing an Alternative Water Processor (AWP) as a candidate water recovery system for long duration exploration missions. The AWP consists of biological water processor (BWP) integrated with a forward osmosis secondary treatment system (FOST). The basis of the BWP is a membrane aerated biological reactor (MABR), developed in concert with Texas Tech University. Bacteria located within the MABR metabolize organic material in wastewater, converting approximately 90% of the total organic carbon to carbon dioxide. In addition, bacteria convert a portion of the ammonia-nitrogen present in the wastewater to nitrogen gas, through a combination of nitrification and denitrification. The effluent from the BWP system is low in organic contaminants, but high in total dissolved solids. The FOST system, integrated downstream of the BWP, removes dissolved solids through a combination of concentration-driven forward osmosis and pressure driven reverse osmosis. The integrated system is expected to produce water with a total organic carbon less than 50 mg/l and dissolved solids that meet potable water requirements for spaceflight. This paper describes the test definition, the design of the BWP and FOST subsystems, and plans for integrated testing.

  19. Reproductive effects of alternative disinfectants

    SciTech Connect

    Carlton, B.D.; Barlett, P.; Basaran, A.; Colling, K.; Osis, I.; Smith, M.K.

    1986-11-01

    Organohalides formed through the reaction of chlorine and organic compounds in natural and waste waters pose potential health hazards. For this reason, alternative water disinfectants that do not form organohalides are being investigated with great interest. In this laboratory, the authors have examined the reproductive effects of chloramine and chlorine administered by gavage in Long-Evans rats. Animals were treated for a total of 66 to 76 days. Males were treated for 56 days and females for 14 days prior to breeding and throughout the 10-day breeding period. Females were treated throughout gestation and lactation. Following breeding, the males were necropsied and evaluated for sperm parameters and reproductive tract histopathology. Adult females and some pups were necropsied at weaning on postnatal day 21. Other pups were treated postweaning until 28 or 40 days of age. These pups were evaluated for the day of vaginal patency and thyroid hormone levels. No differences were observed between control rats and those rats exposed to up to 5 mg/kg/day chlorine or 10 mg/kg/day chloramine when fertility, viability, litter size, day of eye opening, or day of vaginal patency were evaluated. No alterations in sperm count, sperm direct progressive movement percent motility, or sperm morphology were observed among adult male rats. In addition, male and female reproductive organ weights were comparable to their respective control groups, and no significant histopathologic changes were observed among chlorine- or chloramine-treated male and female rats.

  20. Polyandry and alternative mating tactics

    PubMed Central

    Neff, Bryan D.; Svensson, Erik I.

    2013-01-01

    Many species in the animal kingdom are characterized by alternative mating tactics (AMTs) within a sex. In males, such tactics include mate guarding versus sneaking behaviours, or territorial versus female mimicry. Although AMTs can occur in either sex, they have been most commonly described in males. This sex bias may, in part, reflect the increased opportunity for sexual selection that typically exists in males, which can result in a higher probability that AMTs evolve in that sex. Consequently, females and polyandry can play a pivotal role in governing the reproductive success associated with male AMTs and in the evolutionary dynamics of the tactics. In this review, we discuss polyandry and the evolution of AMTs. First, we define AMTs and review game theoretical and quantitative genetic approaches used to model their evolution. Second, we review several examples of AMTs, highlighting the roles that genes and environment play in phenotype expression and development of the tactics, as well as empirical approaches to differentiating among the mechanisms. Third, ecological and genetic constraints to the evolution of AMTs are discussed. Fourth, we speculate on why female AMTs are less reported on in the literature than male tactics. Fifth, we examine the effects of AMTs on breeding outcomes and female fitness, and as a source, and possibly also a consequence, of sexual conflict. We conclude by suggesting a new model for the evolution of AMTs that incorporates both environmental and genetic effects, and discuss some future avenues of research. PMID:23339236

  1. Canonical and alternative MAPK signaling.

    PubMed

    Pimienta, Genaro; Pascual, Jaime

    2007-11-01

    The archetype of MAPK cascade activation is somewhat challenged by the most recent discovery of unexpected phosphorylation patterns, alternative activation mechanisms and sub-cellular localization, in various members of this protein kinase family. In particular, activation by autophosphorylation pathways has now been described for the three best understood MAPK subgroups: ERK1/2; JNK1/2 and p38 alpha/beta. Also, a form of dosage compensation between homologs has been shown to occur in the case of ERK1/2 and JNK1/2. In this paper we summarize the MAPK activation pathway, with an emphasis on non-canonical examples. We use this information to propose a model for MAPK signal transduction that considers a cross-talk between MAPKs with different activation loop sequence motifs and unique C-terminal extensions. We highlight the occurrence of non-canonical substrate specificity during MAPK auto-activation, in strong connection with MAPK homo- and hetero-dimerization events.

  2. Alternative Energy for Higher Education

    SciTech Connect

    Michael Cherney, PhD

    2012-02-22

    This project provides educational opportunities creating both a teaching facility and center for public outreach. The facility is the largest solar array in Nebraska. It was designed to allow students to experience a variety of technologies and provide the public with opportunities for exposure to the implementation of an alternative energy installation designed for an urban setting. The project integrates products from 5 panel manufacturers (including monocrystalline, polycrystalline and thin film technologies) mounted on both fixed and tracking structures. The facility uses both micro and high power inverters. The majority of the system was constructed to serve as an outdoor classroom where panels can be monitored, tested, removed and replaced by students. As an educational facility it primarily serves students in the Creighton University and Metropolitan Community College, but it also provides broader educational opportunities. The project includes a real-time dashboard and a historical database of the output of individual inverters and the corresponding meteorological data for researcher and student use. This allows the evaluation of both panel types and the feasibility of installation types in a region of the country subject to significant temperature, wind and precipitation variation.

  3. Alternative Water Processor Test Development

    NASA Technical Reports Server (NTRS)

    Pickering, Karen D.; Mitchell, Julie; Vega, Leticia; Adam, Niklas; Flynn, Michael; Wjee (er. Rau); Lunn, Griffin; Jackson, Andrew

    2012-01-01

    The Next Generation Life Support Project is developing an Alternative Water Processor (AWP) as a candidate water recovery system for long duration exploration missions. The AWP consists of biological water processor (BWP) integrated with a forward osmosis secondary treatment system (FOST). The basis of the BWP is a membrane aerated biological reactor (MABR), developed in concert with Texas Tech University. Bacteria located within the MABR metabolize organic material in wastewater, converting approximately 90% of the total organic carbon to carbon dioxide. In addition, bacteria convert a portion of the ammonia-nitrogen present in the wastewater to nitrogen gas, through a combination of nitrogen and denitrification. The effluent from the BWP system is low in organic contaminants, but high in total dissolved solids. The FOST system, integrated downstream of the BWP, removes dissolved solids through a combination of concentration-driven forward osmosis and pressure driven reverse osmosis. The integrated system is expected to produce water with a total organic carbon less than 50 mg/l and dissolved solids that meet potable water requirements for spaceflight. This paper describes the test definition, the design of the BWP and FOST subsystems, and plans for integrated testing.

  4. An Alternative to Laser Cooling

    NASA Astrophysics Data System (ADS)

    Raizen, Mark

    2015-03-01

    Laser cooling has been the standard approach for over thirty years for cooling the translational motion of atoms. While laser cooling is an extremely successful method, it has been limited to a small set of elements in the periodic table. The performance of laser cooling for those elements has saturated in terms of flux of ultra-cold atoms, density, and phase-space density. I report our progress towards the development of an alternative to laser cooling. Our approach relies on magnetic stopping of supersonic beams, an atomic coilgun. A recent advance is the experimental realization of an adiabatic coilgun which preserves phase-space density. Further cooling was demonstrated with a one-way wall, realizing the historic thought experiment of Maxwell's Demon. More recently, we showed how to apply this method to compress atomic phase space with almost no loss of atom number. Our approach is fundamentally different than laser cooling as it does not rely on the momentum of the photon, but rather the photon entropy. I will report on our experimental progress towards this goal, and describe future experiments that will be enabled by this work.

  5. Economics of alternative energy sources.

    PubMed

    Ryle, M

    1977-05-12

    An important part of the oil and natural gas at present consumed in the UK is used for the heating of buildings, a demand which shows large diurnal, day-to-day and annual fluctuations. The replacement of this energy by nuclear-generated electricity, as at present envisaged, would require the construction of some 250 GW of additional capacity by the end of the century, a progamme which does not seem feasible. By incorporating relatively cheap, short term storage in the form of low-grade heat, the generating capacity required to fulfil peak demand could be reduced by more than 50%. As soon as such storage is provided, however, other sources of energy become viable and attractive alternatives, and the UK is well situated to make use of wind, wave, and tidal power. It seems likely that the value of North Sea oil/gas reserves as feedstock to the chemical industry will rise sufficiently to make an early reduction in their consumption as fuel of great economic importance.

  6. Phytoremediation -- a practical capping alternative

    SciTech Connect

    Beath, J.M.; Peak, M.J.

    1997-12-31

    Much literature has been devoted recently to the use of various plant species for the uptake of heavy metals and organic contaminants. Other uses for plants as part of the remediation process are growing in perceived effectiveness. Consequently, this paper deals with two other equally important potential uses of plants to address environmental problems that are just now evolving to the field trial stage: the use of plants to remediate organic pollutants; and the use of plants to control the rainfall-driven leaching of contaminants and the subsequent delivery to underlying groundwater. The traditional Resource Conservation and Recovery Act (RCRA) approach to capping landfills will be contrasted with the potential benefits of using plants that can balance incoming rainfall with evapotranspiration, as well as plants which can act on organic constituents in soil or sludge by either uptake or by promoting microbial activity in soil. This paper compares traditional RCRA capping costs to those for a phytoremediation capping alternative, whose benefits include significantly lower implementation cost and continued remediation. This paper discusses important elements of a successful approach to phytoremediation including: species selection, implementation techniques, cost-efficient monitoring, regulatory aspects, project timing, and realistic expectations.

  7. Alternative to Nitric Acid Passivation

    NASA Technical Reports Server (NTRS)

    Kessel, Kurt R.

    2015-01-01

    The Ground Systems Development and Operations (GSDO) Program at NASA John F. Kennedy Space Center (KSC), Florida, has the primary objective of modernizing and transforming the launch and range complex at KSC to benefit current and future NASA programs along with other emerging users. Described as the launch support and infrastructure modernization program in the NASA Authorization Act of 2010, the GSDO Program will develop and implement shared infrastructure and process improvements to provide more flexible, affordable, and responsive capabilities to a multi-user community. In support of NASA and the GSDO Program, the objective of this project is to qualify citric acid as an environmentally-preferable alternative to nitric acid for passivation of stainless steel alloys. This project is a direct follow-on to United Space Alliance (USA) work at KSC to optimize the parameters for the use of citric acid and verify effectiveness. This project will build off of the USA study to further evaluate citric acids effectiveness and suitability for corrosion protection of a number of stainless steels alloys used by NASA, the Department of Defense (DoD), and the European Space Agency (ESA).

  8. Alternatives to traditional transportation fuels: An overview

    SciTech Connect

    Not Available

    1994-06-01

    This report presents the first compilation by the Energy Information Administration (EIA) of information on alternatives to gasoline and diesel fuel. The purpose of the report is: (1) to provide background information on alternative transportation fuels and replacement fuels compared with gasoline and diesel fuel, and (2) to furnish preliminary estimates of alternative transportation fuels and alternative fueled vehicles as required by the Energy Policy Act of 1992 (EPACT), Title V, Section 503, ``Replacement Fuel Demand Estimates and Supply Information.`` Specifically, Section 503 requires the EIA to report annually on: (1) the number and type of alternative fueled vehicles in existence the previous year and expected to be in use the following year, (2) the geographic distribution of these vehicles, (3) the amounts and types of replacement fuels consumed, and (4) the greenhouse gas emissions likely to result from replacement fuel use. Alternative fueled vehicles are defined in this report as motorized vehicles licensed for on-road use, which may consume alternative transportation fuels. (Alternative fueled vehicles may use either an alternative transportation fuel or a replacement fuel.) The intended audience for the first section of this report includes the Secretary of Energy, the Congress, Federal and State agencies, the automobile manufacturing industry, the transportation fuel manufacturing and distribution industries, and the general public. The second section is designed primarily for persons desiring a more technical explanation of and background for the issues surrounding alternative transportation fuels.

  9. Alternative medicine and the family physician.

    PubMed

    Gordon, J S

    1996-11-15

    The seven categories of alternative medicine, as established by the National Institutes of Health Office of Alternative Medicine, are mind-body interventions, bioelectromagnetic therapies, alternative systems of medical practice, manual healing methods, pharmacologic and biologic treatments, herbal medicine, and diet and nutrition. Mind-body approaches have been shown to be effective in a variety of conditions. Acupuncture and homeopathy are alternative systems of medical practice that may be beneficial. Chiropractic manipulation for low back pain and infant message for enhancing growth are two methods of manual healing. While the literature on herbal medicine is vast, most of it focuses on a single approach for a specific condition. Traditional herbalists use a combination of herbs individualized for the specific person. As more and more people turn to alternative therapies, it is important for family physicians to be open to their patients' interest in alternative approaches.

  10. Display Sharing: An Alternative Paradigm

    NASA Technical Reports Server (NTRS)

    Brown, Michael A.

    2010-01-01

    The current Johnson Space Center (JSC) Mission Control Center (MCC) Video Transport System (VTS) provides flight controllers and management the ability to meld raw video from various sources with telemetry to improve situational awareness. However, maintaining a separate infrastructure for video delivery and integration of video content with data adds significant complexity and cost to the system. When considering alternative architectures for a VTS, the current system's ability to share specific computer displays in their entirety to other locations, such as large projector systems, flight control rooms, and back supporting rooms throughout the facilities and centers must be incorporated into any new architecture. Internet Protocol (IP)-based systems also support video delivery and integration. IP-based systems generally have an advantage in terms of cost and maintainability. Although IP-based systems are versatile, the task of sharing a computer display from one workstation to another can be time consuming for an end-user and inconvenient to administer at a system level. The objective of this paper is to present a prototype display sharing enterprise solution. Display sharing is a system which delivers image sharing across the LAN while simultaneously managing bandwidth, supporting encryption, enabling recovery and resynchronization following a loss of signal, and, minimizing latency. Additional critical elements will include image scaling support, multi -sharing, ease of initial integration and configuration, integration with desktop window managers, collaboration tools, host and recipient controls. This goal of this paper is to summarize the various elements of an IP-based display sharing system that can be used in today's control center environment.

  11. Alternative to particle dark matter

    NASA Astrophysics Data System (ADS)

    Khoury, Justin

    2015-01-01

    We propose an alternative to particle dark matter that borrows ingredients of modified Newtonian dynamics (MOND) while adding new key components. The first new feature is a dark matter fluid, in the form of a scalar field with small equation of state and sound speed. This component is critical in reproducing the success of cold dark matter for the expansion history and the growth of linear perturbations, but does not cluster significantly on nonlinear scales. Instead, the missing mass problem on nonlinear scales is addressed by a modification of the gravitational force law. The force law approximates MOND at large and intermediate accelerations, and therefore reproduces the empirical success of MOND at fitting galactic rotation curves. At ultralow accelerations, the force law reverts to an inverse-square law, albeit with a larger Newton's constant. This latter regime is important in galaxy clusters and is consistent with their observed isothermal profiles, provided the characteristic acceleration scale of MOND is mildly varying with scale or mass, such that it is 12 times higher in clusters than in galaxies. We present an explicit relativistic theory in terms of two scalar fields. The first scalar field is governed by a Dirac-Born-Infeld action and behaves as a dark matter fluid on large scales. The second scalar field also has single-derivative interactions and mediates a fifth force that modifies gravity on nonlinear scales. Both scalars are coupled to matter via an effective metric that depends locally on the fields. The form of this effective metric implies the equality of the two scalar gravitational potentials, which ensures that lensing and dynamical mass estimates agree. Further work is needed in order to make both the acceleration scale of MOND and the fraction at which gravity reverts to an inverse-square law explicitly dynamical quantities, varying with scale or mass.

  12. EUVL alternating phase shift mask

    NASA Astrophysics Data System (ADS)

    Yan, Pei-Yang; Myers, Alan; Shroff, Yashesh; Chandhok, Manish; Zhang, Guojing; Gullikson, Eric; Salmassi, Farhad

    2011-04-01

    Extreme ultra-violet Lithography (EUVL) alternating phase shift mask (APSM) or other optical enhancement techniques are likely needed for 16nm (half pitch) technology generation and beyond. One possible option is the combination of EUVL and APSM. The fabrication of EUVL APSM is more difficult than either the fabrication of an EUVL binary mask or a conventional optical APSM mask. In the case of EUVL APSM, the phase difference in the two regions (0 and 180-degree phase regions) is created by a phase step in the substrate prior to the multilayer (ML) coating. The step height that induces 180-degree phase mismatch in the ML is determined by [λ/(4cosθ)](2m+1), where m are integers (0, 1, 2,...). In this experiment, we targeted for a step height with m=1. The same mask design also contains the standard binary structures so that the comparison between the EUVL APSM and the EUVL binary mask can be performed under the same illumination and wafer process conditions. The EUVL APSM mask was exposed using Nikon's EUV1 scanner in Kumagaya Japan. The wafer level results showed higher dense line resolution for EUVL APSM as compared to that of EUVL binary mask. APSM also showed improved line width roughness (LWR) and depth of focus (DoF) as compared to the best EUVL binary results obtained with C-dipole off-axis illumination (OAI). The wafer CD resolution improvement obtained by APSM in this experiment is partially limited by the resist resolution and the mask phase edge spread during ML deposition. We believe that wafer CD resolution and can further be improved with imaging imbalance compensation mask design and improvements in resist resolution and the phase generation portion of the mask fabrication process. In this paper, we will discuss in detail the mask fabrication process, wafer level data analysis, and our understanding of EUVL APSM related issues.

  13. Reproductive effects of alternative disinfectants.

    PubMed

    Carlton, B D; Barlett, P; Basaran, A; Colling, K; Osis, I; Smith, M K

    1986-11-01

    Organohalides formed through the reaction of chlorine and organic compounds in natural and waste waters pose potential health hazards. For this reason, alternative water disinfectants that do not form organohalides are being investigated with great interest. Limited data are available on the health effects, in particular reproductive toxicity effects, of these compounds. In our laboratory, we have examined the reproductive effects of chloramine and chlorine administered by gavage in Long-Evans rats. Animals were treated for a total of 66 to 76 days. Males were treated for 56 days and females for 14 days prior to breeding and throughout the 10-day breeding period. Females were treated throughout gestation and lactation. Following breeding, the males were necropsied and evaluated for sperm parameters and reproductive tract histopathology. Adult females and some pups were necropsied at weaning on postnatal day 21. Other pups were treated postweaning until 28 or 40 days of age. These pups were evaluated for the day of vaginal patency and thyroid hormone levels. No differences were observed between control rats and those rats exposed to up to 5 mg/kg/day chlorine or 10 mg/kg/day chloramine when fertility, viability, litter size, day of eye opening, or day of vaginal patency were evaluated. No alterations in sperm count, sperm direct progressive movement (micron/sec), percent motility, or sperm morphology were observed among adult male rats. In addition, male and female reproductive organ weights were comparable to their respective control groups, and no significant histopathologic changes were observed among chlorine- or chloramine-treated male and female rats.

  14. Alternative Neutron Detection Testing Summary

    SciTech Connect

    Kouzes, Richard T.; Ely, James H.; Erikson, Luke E.; Kernan, Warnick J.; Lintereur, Azaree T.; Siciliano, Edward R.; Stromswold, David C.; Woodring, Mitchell L.

    2010-04-08

    Radiation portal monitors used for interdiction of illicit materials at borders include highly sensitive neutron detection systems. The main reason for having neutron detection capability is to detect fission neutrons from plutonium. Most currently deployed radiation portal monitors (RPMs) use neutron detectors based upon 3He-filled gas proportional counters, which are the most common large area neutron detector. This type of neutron detector is used in the TSA and other RPMs installed in international locations and in the Ludlum and Science Applications International Corporation RPMs deployed primarily for domestic applications. There is a declining supply of 3He in the world and, thus, methods to reduce the use of this gas in RPMs with minimal changes to the current system designs and sensitivity to cargo-borne neutrons are being investigated. Four technologies have been identified as being currently commercially available, potential alternative neutron detectors to replace the use of 3He in RPMs. These technologies are: 1) Boron trifluoride-filled proportional counters, 2) Boron-lined proportional counters, 3) Lithium-loaded glass fibers, and 4) Coated wavelength-shifting plastic fibers. Reported here is a summary of the testing carried out at Pacific Northwest National Laboratory on these technologies to date, as well as measurements on 3He tubes at various pressures. Details on these measurements are available in the referenced reports. Sponsors of these tests include the Department of Energy (DOE), Department of Homeland Security (DHS), and the Department of Defense (DoD), as well as internal Pacific Northwest National Laboratory funds.

  15. Planetary Protection Alternate Protocol Certification

    NASA Astrophysics Data System (ADS)

    Baker, Amy; Barengoltz, Jack; Tisdale, David

    The talk presents a standardized approach for new method certification or alterative testing protocol (ATP) certification against the existing U.S. Planetary Protection Standards. In consideration of new method certification there are two phases of activities that are relevant to the certification process. The first is sample acquisition which typically incorporates swab or wipes sampling on relevant hardware, associated facilities and ground support equipment. The sampling methods introduce considerations of field sampling efficiency as it relates to spore distribution on the spacecraft, spacecraft material influences on the ability of the swab or wipe to remove spores from the hardware, the types of swabs and wipes used (polyester, cotton, macrofoam), and human sampling influences. The second portion of a new protocol certification looks specifically at the lab work-up or analysis of the samples provided to the laboratory. Variables in this process include selection of appropriate biomarkers, extraction efficiencies (removal of spores or constituents of interest from the sampling device), and a method's ability to accurately determine the number of spores present in the sample with a statistically valid level of confidence as described by parameters such as precision, accuracy, robustness, specificity and sensitivity. Considerations for alternative testing protocols such as those which utilize bioburden reduction techniques include selection of appropriate biomarkers for testing, test materials and a defined statistical approach that provides sufficient scientific data to support the modification of an existing NASA specification or the generation of a new NASA specification. Synergies between the U.S. and European Space Agency approaches will also be discussed.

  16. Use of alternative sweeteners in diabetic diet.

    PubMed

    Crapo, P A

    1988-02-01

    Alternative sweeteners are widely advocated and used. However, there is insufficient scientific information to determine whether alternative sweeteners aer of value in the management of diabetes, either in improving dietary adherence or in contributing to the achievement or maintenance of a lower body weight. Each of the available sweeteners has advantages and disadvantages; no one is preferred. Recommendations about alternative-sweetener use should be tailored to the specific dietary and life-style patterns of the individual.

  17. Methods for Characterization of Alternative RNA Splicing.

    PubMed

    Harvey, Samuel E; Cheng, Chonghui

    2016-01-01

    Quantification of alternative splicing to detect the abundance of differentially spliced isoforms of a gene in total RNA can be accomplished via RT-PCR using both quantitative real-time and semi-quantitative PCR methods. These methods require careful PCR primer design to ensure specific detection of particular splice isoforms. We also describe analysis of alternative splicing using a splicing "minigene" in mammalian cell tissue culture to facilitate investigation of the regulation of alternative splicing of a particular exon of interest.

  18. Alternate Reality Teaching: OurSpace

    DTIC Science & Technology

    2014-05-31

    Alternate Reality Teaching: OurSpace N00014-11-C-0593 Data contained on this page is subject to restrictions on cover and notice page. Intific...Inc. 1 Alternate Reality Teaching: OurSpace May 31, 2014 Sponsored by Defense Advanced Research Projects Agency (DOD) Issued by Office of...REPORT TYPE Final Phase 2 Report 3. DATES COVERED (From - To) 31-05-2012 – 31-05-2014 4. TITLE AND SUBTITLE Alternate Reality Teaching: Our Space

  19. Transitioning to Low-GWP Alternatives in Commercial Refrigeration

    EPA Pesticide Factsheets

    This fact sheet provides information on low-GWP alternatives in commercial refrigeration. It discusses HFC alternatives, market trends, challenges to market entry for alternatives, and potential solutions.

  20. 7 CFR 1220.207 - Alternate members.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE SOYBEAN PROMOTION, RESEARCH, AND CONSUMER INFORMATION Soybean Promotion and Research Order United Soybean Board § 1220.207 Alternate...

  1. 7 CFR 1220.207 - Alternate members.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE SOYBEAN PROMOTION, RESEARCH, AND CONSUMER INFORMATION Soybean Promotion and Research Order United Soybean Board § 1220.207 Alternate...

  2. 7 CFR 1220.207 - Alternate members.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE SOYBEAN PROMOTION, RESEARCH, AND CONSUMER INFORMATION Soybean Promotion and Research Order United Soybean Board § 1220.207 Alternate...

  3. 7 CFR 1220.207 - Alternate members.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE SOYBEAN PROMOTION, RESEARCH, AND CONSUMER INFORMATION Soybean Promotion and Research Order United Soybean Board § 1220.207 Alternate...

  4. 7 CFR 1220.207 - Alternate members.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE SOYBEAN PROMOTION, RESEARCH, AND CONSUMER INFORMATION Soybean Promotion and Research Order United Soybean Board § 1220.207 Alternate...

  5. Evolutionary conservation of alternative splicing in chicken

    PubMed Central

    Katyal, S.; Gao, Z.; Liu, R.-Z.; Godbout, R.

    2013-01-01

    Alternative splicing represents a source of great diversity for regulating protein expression and function. It has been estimated that one-third to two-thirds of mammalian genes are alternatively spliced. With the sequencing of the chicken genome and analysis of transcripts expressed in chicken tissues, we are now in a position to address evolutionary conservation of alternative splicing events in chicken and mammals. Here, we compare chicken and mammalian transcript sequences of 41 alternatively-spliced genes and 50 frequently accessed genes. Our results support a high frequency of splicing events in chicken, similar to that observed in mammals. PMID:17675855

  6. Complementary and Alternative Therapies in ALS

    PubMed Central

    Bedlack, Richard S.; Joyce, Nanette; Carter, Gregory T.; Pagononi, Sabrina; Karam, Chafic

    2015-01-01

    Synopsis Given the severity of their illness and lack of effective disease modifying agents, it is not surprising that most patients with ALS consider trying complementary and alternative therapies. Some of the most commonly considered alternative therapies include special diets, nutritional supplements, cannabis, acupuncture, chelation and energy healing. This chapter reviews these in detail. We also describe 3 models by which physicians may frame discussions about alternative therapies: paternalism, autonomy and shared decision making. Finally, we review a program called ALSUntangled which using shared shared decision making to review alternative therapies for ALS. PMID:26515629

  7. Alcoholism and alternative splicing of candidate genes.

    PubMed

    Sasabe, Toshikazu; Ishiura, Shoichi

    2010-04-01

    Gene expression studies have shown that expression patterns of several genes have changed during the development of alcoholism. Gene expression is regulated not only at the level of transcription but also through alternative splicing of pre-mRNA. In this review, we discuss some of the evidence suggesting that alternative splicing of candidate genes such as DRD2 (encoding dopamine D2 receptor) may form the basis of the mechanisms underlying the pathophysiology of alcoholism. These reports suggest that aberrant expression of splice variants affects alcohol sensitivities, and alcohol consumption also regulates alternative splicing. Thus, investigations of alternative splicing are essential for understanding the molecular events underlying the development of alcoholism.

  8. Alternate Energy from the Desert

    NASA Astrophysics Data System (ADS)

    Malek, E.

    2003-12-01

    Due to rapid growth of the world's population and more demands for energy, and due to limited amount of fossil fuels (which provide 95 % of the world's energy needs), harnessing of alternate energy sources such as solar and wind power should be considered. In addition to the mountain passes with usually high wind, vast and flat desert areas could be good candidates for harvesting both solar and wind power. We set up a weather station in the middle of a desert, approximately 65 km east-west by 130 km north-south, located at Dugway (40\\deg 08' N, 113\\deg 27' W, 1124 m above mean sea level) in northwestern Utah, USA, in 1999. This station measured the incoming (Rsi) and outgoing (Rso) solar or shortwave radiation using two CM21 Kipp & Zonen pyranometers (one inverted), the incoming (Rli or atmospheric) and outgoing (Rlo or terrestrial) longwave radiation, using two CG1 Kipp & Zonen pyrgeometers (one inverted), and the net (Rn) radiation using a Q*7 net radiometer (Radiation Energy Balance System, REBS). We also measured the 3-m wind speed (U3) and direction (R.M. Young wind monitor) and precipitation (Campbell Sci., Inc.) and some other weather parameters. The measurements were taken every two seconds, and averaged into 20-min, continuously, throughout the year. The two-year (January 2000 - December 2001) period comparisons of global or solar radiation and windiness with two other stations in central (Hunter) and northern (Logan) Utah, indicate higher average solar radiation [Rsi,Dugway = 601 MJ / (m2-month) vs. Rsi, Hunter = 5371 MJ /(m2-month) and Rsi, Logan = 516 MJ /(m2-month)] and much higher 10-m average wind (UDugway = 478 km/d vs. UHunter = 323 km/d and ULogan = 275 km/d) throughout the period over the desert. These data reveal the possibility of simultaneously harvesting these two sources of clean energies at this vast and uniform desert area. Keywords: Desert, energy, radiation balance, solar and wind energies, windiness.

  9. Leveraging structure determination with fragment screening for infectious disease drug targets: MECP synthase from Burkholderia pseudomallei

    SciTech Connect

    Begley, Darren W.; Hartley, Robert C.; Davies, Douglas R.; Edwards, Thomas E.; Leonard, Jess T.; Abendroth, Jan; Burris, Courtney A.; Bhandari, Janhavi; Myler, Peter J.; Staker, Bart L.; Stewart, Lance J.

    2011-09-28

    As part of the Seattle Structural Genomics Center for Infectious Disease, we seek to enhance structural genomics with ligand-bound structure data which can serve as a blueprint for structure-based drug design. We have adapted fragment-based screening methods to our structural genomics pipeline to generate multiple ligand-bound structures of high priority drug targets from pathogenic organisms. In this study, we report fragment screening methods and structure determination results for 2C-methyl-D-erythritol-2,4-cyclo-diphosphate (MECP) synthase from Burkholderia pseudomallei, the gram-negative bacterium which causes melioidosis. Screening by nuclear magnetic resonance spectroscopy as well as crystal soaking followed by X-ray diffraction led to the identification of several small molecules which bind this enzyme in a critical metabolic pathway. A series of complex structures obtained with screening hits reveal distinct binding pockets and a range of small molecules which form complexes with the target. Additional soaks with these compounds further demonstrate a subset of fragments to only bind the protein when present in specific combinations. This ensemble of fragment-bound complexes illuminates several characteristics of MECP synthase, including a previously unknown binding surface external to the catalytic active site. These ligand-bound structures now serve to guide medicinal chemists and structural biologists in rational design of novel inhibitors for this enzyme.

  10. The plastidial retrograde signal methyl erythritol cyclopyrophosphate is a regulator of salicylic acid and jasmonic acid crosstalk.

    PubMed

    Lemos, Mark; Xiao, Yanmei; Bjornson, Marta; Wang, Jin-Zheng; Hicks, Derrick; Souza, Amancio de; Wang, Chang-Quan; Yang, Panyu; Ma, Shisong; Dinesh-Kumar, Savithramma; Dehesh, Katayoon

    2016-03-01

    The exquisite harmony between hormones and their corresponding signaling pathways is central to prioritizing plant responses to simultaneous and/or successive environmental trepidations. The crosstalk between jasmonic acid (JA) and salicylic acid (SA) is an established effective mechanism that optimizes and tailors plant adaptive responses. However, the underlying regulatory modules of this crosstalk are largely unknown. Global transcriptomic analyses of mutant plants (ceh1) with elevated levels of the stress-induced plastidial retrograde signaling metabolite 2-C-methyl-D-erythritol cyclopyrophosphate (MEcPP) revealed robustly induced JA marker genes, expected to be suppressed by the presence of constitutively high SA levels in the mutant background. Analyses of a range of genotypes with varying SA and MEcPP levels established the selective role of MEcPP-mediated signal(s) in induction of JA-responsive genes in the presence of elevated SA. Metabolic profiling revealed the presence of high levels of the JA precursor 12-oxo-phytodienoic acid (OPDA), but near wild type levels of JA in the ceh1 mutant plants. Analyses of coronatine-insensitive 1 (coi1)/ceh1 double mutant plants confirmed that the MEcPP-mediated induction is JA receptor COI1 dependent, potentially through elevated OPDA. These findings identify MEcPP as a previously unrecognized central regulatory module that induces JA-responsive genes in the presence of high SA, thereby staging a multifaceted plant response within the environmental context.

  11. Methylerythritol phosphate pathway to isoprenoids: kinetic modeling and in silico enzyme inhibitions in Plasmodium falciparum.

    PubMed

    Singh, Vivek Kumar; Ghosh, Indira

    2013-09-02

    The methylerythritol phosphate (MEP) pathway of Plasmodium falciparum (P. falciparum) has become an attractive target for anti-malarial drug discovery. This study describes a kinetic model of this pathway, its use in validating 1-deoxy-d-xylulose 5-phosphate reductoisomerase (DXR) as drug target from the systemic perspective, and additional target identification, using metabolic control analysis and in silico inhibition studies. In addition to DXR, 1-deoxy-d-xylulose 5-phosphate synthase (DXS) can be targeted because it is the first enzyme of the pathway and has the highest flux control coefficient followed by that of DXR. In silico inhibition of both enzymes caused large decrement in the pathway flux. An added advantage of targeting DXS is its influence on vitamin B1 and B6 biosynthesis. Two more potential targets, 2-C-methyl-d-erythritol 2,4-cyclodiphosphate synthase and 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate synthase, were also identified. Their inhibition caused large accumulation of their substrates causing instability of the system. This study demonstrates that both types of enzyme targets, one acting via flux reduction and the other by metabolite accumulation, exist in P. falciparum MEP pathway. These groups of targets can be exploited for independent anti-malarial drugs.

  12. Perspectives in anti-infective drug design. The late steps in the biosynthesis of the universal terpenoid precursors, isopentenyl diphosphate and dimethylallyl diphosphate.

    PubMed

    Rohdich, Felix; Bacher, Adelbert; Eisenreich, Wolfgang

    2004-10-01

    A mevalonate-independent pathway for the biosynthesis of isopentenyl diphosphate (IPP) and dimethylallyl diphosphate (DMAPP) that has been elucidated during the last decade is essential in plants, many eubacteria and apicomplexan parasites, but is absent in Archaea and animals. The enzymes of the pathway are potential targets for the development of novel antibiotic, antimalarial and herbicidal agents. This review is focused on the late steps of this pathway. The intermediate 2C-methyl-D-erythritol 2,4-cyclodiphosphate is converted into IPP and DMAPP via 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate by the consecutive action of the iron-sulfur proteins IspG and IspH. IPP and DMAPP can be interconverted by IPP isomerase which is essential in microorganisms using the mevalonate pathway, whereas its presence is optional in microorganisms using the non-mevalonate pathway. A hitherto unknown family of IPP isomerases using FMN as coenzyme has been discovered recently in Archaea and certain eubacteria.

  13. In situ localization of gene transcriptions for monoterpene synthesis in irregular parenchymic cells surrounding the secretory cavities in rough lemon (Citrus jambhiri).

    PubMed

    Yamasaki, Yumiko; Akimitsu, Kazuya

    2007-11-01

    A cDNA (RlemispF) encoding 2-C-methyl-d-erythritol 2,4-cyclodiphosphate synthase, an enzyme of the methyl erythritol phosphate (MEP) pathway, and two homologs (RlemTPS1 and RlemTPS2) of citrus monoterpene synthase cDNA were isolated from the rough lemon (Citrus jambhiri). Transient localization of all or a part of RlemispF fused to a green fluorescence protein using particle gun-mediated DNA delivery localized RlemispF in the chloroplast. Transcripts of RlemispF and other monoterpene synthase genes are constitutively expressed in leaves of rough lemon. Transcript accumulations of RlemispF and RlemTPS1 were not induced by microbe attacks, but microbe attack weakly induced RlemTPS2 expression. Wounding decreased RlemispF expression. RlemispF and two different monoterpene synthase genes were specifically expressed in the epithelial tissue cells with dense cytoplasm that surround secretory cavities, which form a broadly round package containing a large volume of essential oils composed of monoterpenes. Interestingly, although expressions of RlemTPS1 and RlemTPS2 were detected at both mature and developing secretory cavities, the RlemispF-expressing cells were found more at around developing secretory cavities.

  14. 28 CFR 42.734 - Alternative funding.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 28 Judicial Administration 1 2013-07-01 2013-07-01 false Alternative funding. 42.734 Section 42.734 Judicial Administration DEPARTMENT OF JUSTICE NONDISCRIMINATION; EQUAL EMPLOYMENT OPPORTUNITY...; Implementation of the Age Discrimination Act of 1975 Compliance Procedures § 42.734 Alternative funding....

  15. 28 CFR 42.734 - Alternative funding.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 28 Judicial Administration 1 2012-07-01 2012-07-01 false Alternative funding. 42.734 Section 42.734 Judicial Administration DEPARTMENT OF JUSTICE NONDISCRIMINATION; EQUAL EMPLOYMENT OPPORTUNITY...; Implementation of the Age Discrimination Act of 1975 Compliance Procedures § 42.734 Alternative funding....

  16. 28 CFR 42.734 - Alternative funding.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Alternative funding. 42.734 Section 42.734 Judicial Administration DEPARTMENT OF JUSTICE NONDISCRIMINATION; EQUAL EMPLOYMENT OPPORTUNITY...; Implementation of the Age Discrimination Act of 1975 Compliance Procedures § 42.734 Alternative funding....

  17. 28 CFR 42.734 - Alternative funding.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 28 Judicial Administration 1 2014-07-01 2014-07-01 false Alternative funding. 42.734 Section 42.734 Judicial Administration DEPARTMENT OF JUSTICE NONDISCRIMINATION; EQUAL EMPLOYMENT OPPORTUNITY...; Implementation of the Age Discrimination Act of 1975 Compliance Procedures § 42.734 Alternative funding....

  18. 28 CFR 42.734 - Alternative funding.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 28 Judicial Administration 1 2011-07-01 2011-07-01 false Alternative funding. 42.734 Section 42.734 Judicial Administration DEPARTMENT OF JUSTICE NONDISCRIMINATION; EQUAL EMPLOYMENT OPPORTUNITY...; Implementation of the Age Discrimination Act of 1975 Compliance Procedures § 42.734 Alternative funding....

  19. Alternative Certification Pathways: Filling a Gap?

    ERIC Educational Resources Information Center

    Ludlow, Carlyn

    2013-01-01

    The purpose of this article is to examine the proliferation of alternative certification pathways through an analysis of the role and history of teacher certification and supply followed by a synthesis of national, regional, and state research studies on alternative routes to certification programs and a review of studies conducted on well-known…

  20. Alternatives for Financing Higher Education Facilities.

    ERIC Educational Resources Information Center

    Leslie, Larry L.; Felix, Frank J.

    1980-01-01

    How state governments should finance public college and university facilities is discussed. A framework for analyzing the capital financing alternatives available to state governments is described. Several alternatives in Arizona--including state appropriations, leasing, and revenue bonding--are considered as an illustration. (Author/MLW)

  1. Alternative Asbestos Control Method (AACM) Research

    EPA Science Inventory

    This presentation describes the status to date of the Alternative Asbestos Control Method research, which is intended as a possible alternative technology for use in the demolition of buildings that contain asbestos and are covered under the regulatory requirements of the Asbesto...

  2. 30 CFR 47.43 - Label alternatives.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Label alternatives. 47.43 Section 47.43 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR EDUCATION AND TRAINING HAZARD COMMUNICATION (HazCom) Container Labels and Other Forms of Warning § 47.43 Label alternatives. The operator...

  3. 30 CFR 47.43 - Label alternatives.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Label alternatives. 47.43 Section 47.43 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR EDUCATION AND TRAINING HAZARD COMMUNICATION (HazCom) Container Labels and Other Forms of Warning § 47.43 Label alternatives. The operator...

  4. 30 CFR 47.43 - Label alternatives.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Label alternatives. 47.43 Section 47.43 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR EDUCATION AND TRAINING HAZARD COMMUNICATION (HazCom) Container Labels and Other Forms of Warning § 47.43 Label alternatives. The operator...

  5. 30 CFR 47.43 - Label alternatives.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Label alternatives. 47.43 Section 47.43 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR EDUCATION AND TRAINING HAZARD COMMUNICATION (HazCom) Container Labels and Other Forms of Warning § 47.43 Label alternatives. The operator...

  6. Alternatives to Suspension: A Government Initiative

    ERIC Educational Resources Information Center

    Ryan, Thomas G.; Zoldy, Scott

    2011-01-01

    Student discipline and the ineffectiveness of out-of-school suspension is examined in light of the Ontario (Canada) legislative reform that supported a greater emphasis on progressive discipline alternatives to out-of-school suspension. Alternative discipline herein is explored via the behavior education plan, the school survival group, and…

  7. Alternating Skew Deviation from Traumatic Intracranial Hypotension

    PubMed Central

    Moster, Stephen J.; Moster, Mark L.

    2014-01-01

    Abstract A 56-year-old woman developed progressive headache, mental status changes, and diplopia after trauma. She was diagnosed with alternating skew deviation caused by intracranial hypotension. This is the first case of alternating skew deviation reported from intracranial hypotension and perhaps a differential pressure between intracranial and intraspinal spaces plays a role in the development of these findings. PMID:27928294

  8. The Unprepared Discipline: Selection of Alternative Futures.

    ERIC Educational Resources Information Center

    Massengale, John D.

    1988-01-01

    Physical education teachers need to create alternative futures, select the one of their choice, and then take the necessary steps to make this future come true. Background information on futurism, futures research, and ways to consider alternative futures is provided for those who wish to incorporate these concepts into the curriculum. (Author/CB)

  9. 7 CFR 1205.328 - Alternate members.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE COTTON RESEARCH AND PROMOTION Cotton Research and Promotion Order Cotton Board § 1205.328 Alternate members. An alternate member of the... member from the same cotton-producing state or region to serve in such member's place and stead of...

  10. 7 CFR 1205.328 - Alternate members.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE COTTON RESEARCH AND PROMOTION Cotton Research and Promotion Order Cotton Board § 1205.328 Alternate members. An alternate member of the... member from the same cotton-producing state or region to serve in such member's place and stead of...

  11. 7 CFR 1205.328 - Alternate members.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE COTTON RESEARCH AND PROMOTION Cotton Research and Promotion Order Cotton Board § 1205.328 Alternate members. An alternate member of the... member from the same cotton-producing state or region to serve in such member's place and stead of...

  12. Alternatives to traditional transportation fuels 1996

    SciTech Connect

    1997-12-01

    Interest in alternative transportation fuels (ATF`s) has increased in recent years due to the drives for cleaner air and less dependence upon foreign oil. This report, Alternatives to Traditional Transportation Fuels 1996, provides information on ATFs, as well as the vehicles that consume them.

  13. Renewal, resurgence, and alternative reinforcement context.

    PubMed

    Sweeney, Mary M; Shahan, Timothy A

    2015-07-01

    Resurgence, relapse induced by the removal of alternative reinforcement, and renewal, relapse induced by a change in contextual stimuli, are typically studied separately in operant conditioning paradigms. In analogous treatments of operant problem behavior, aspects of both relapse phenomena can operate simultaneously. Therefore, the purpose of this study was to examine a novel method for studying resurgence and renewal in the same experimental preparation. An alternative source of reinforcement was available during extinction for one group of rats (a typical resurgence preparation). Another group experienced an operant renewal preparation in which the extinction context was distinguished via olfactory and visual stimuli. A third group experienced alternative reinforcement delivery in the new context, a novel combination of typical resurgence and renewal preparations. Removal of alternative reinforcement and/or a change in context induced relapse relative to an extinction-only control group. When alternative reinforcement was delivered in a novel context, the alternative response was less persistent relative to when extinction of the alternative response took place in the context in which it was trained. This methodology might be used to illustrate shared (or distinct) mechanisms of resurgence and renewal, and to determine how delivering alternative reinforcement in another context may affect persistence and relapse.

  14. 7 CFR 1216.45 - Alternate members.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE PEANUT PROMOTION, RESEARCH, AND INFORMATION ORDER Peanut Promotion, Research, and Information Order National Peanut Board § 1216.45 Alternate members. An alternate member of the Board, during the absence of the member for the primary...

  15. 7 CFR 1216.45 - Alternate members.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE PEANUT PROMOTION, RESEARCH, AND INFORMATION ORDER Peanut Promotion, Research, and Information Order National Peanut Board § 1216.45 Alternate members. An alternate member of the Board, during the absence of the member for the primary...

  16. 7 CFR 1216.45 - Alternate members.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE PEANUT PROMOTION, RESEARCH, AND INFORMATION ORDER Peanut Promotion, Research, and Information Order National Peanut Board § 1216.45 Alternate members. An alternate member of the Board, during the absence of the member for the primary...

  17. 7 CFR 1216.45 - Alternate members.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE PEANUT PROMOTION, RESEARCH, AND INFORMATION ORDER Peanut Promotion, Research, and Information Order National Peanut Board § 1216.45 Alternate members. An alternate member of the Board, during the absence of the member for the primary...

  18. 7 CFR 1216.45 - Alternate members.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE PEANUT PROMOTION, RESEARCH, AND INFORMATION ORDER Peanut Promotion, Research, and Information Order National Peanut Board § 1216.45 Alternate members. An alternate member of the Board, during the absence of the member for the primary...

  19. Context-driven expectations about focus alternatives

    PubMed Central

    Kim, Christina S.; Gunlogson, Christine; Tanenhaus, Michael K.; Runner, Jeffrey T.

    2015-01-01

    What is conveyed by a sentence frequently depends not only on the descriptive content carried by its words, but also on implicit alternatives determined by the context of use. Four visual world eye-tracking experiments examined how alternatives are generated based on aspects of the discourse context and used in interpreting sentences containing the focus operators only and also. Experiment 1 builds on previous reading time studies showing that the interpretations of only sentences are constrained by alternatives explicitly mentioned in the preceding discourse, providing fine-grained time course information about the expectations triggered by only. Experiments 2 and 3 show that, in the absence of explicitly mentioned alternatives, lexical and situation-based categories evoked by the context are possible sources of alternatives. While Experiments 1-3 all demonstrate the discourse dependence of alternatives, only explicit mention triggered expectations about alternatives that were specific to sentences with only. By comparing only with also, Experiment 4 begins to disentangle expectations linked to the meanings of specific operators from those generalizable to the class of focus-sensitive operators. Together, these findings show that the interpretation of sentences with focus operators draws on both dedicated mechanisms for introducing alternatives into the discourse context and general mechanisms associated with discourse processing. PMID:25797456

  20. An Alternative Starting Point for Fraction Instruction

    ERIC Educational Resources Information Center

    Cortina, José Luis; Višnovská, Jana; Zúñiga, Claudia

    2015-01-01

    We analyze the results of a study conducted for the purpose of assessing the viability of an alternative starting point for teaching fractions. The alternative is based on Freudenthal's insights about fraction as comparison. It involves portraying the entities that unit fractions quantify as always being apart from the reference unit, instead of…

  1. SKOLE: The Journal of Alternative Education, 1996.

    ERIC Educational Resources Information Center

    Leue, Mary, Ed.

    1996-01-01

    The four issues of "SKOLE" published in 1996 include articles about alternatives to public education, the value of free schools and home-schooling, and children's learning experiences. Feature articles include profiles of alternative schools and educational programs; descriptions of learning experiences and teaching practices; a study of full…

  2. Alternance Training in Texas: A Preliminary Overview.

    ERIC Educational Resources Information Center

    Glover, Robert W.; Shelton, Elaine

    A study was undertaken to identify and evaluate state-of-the-art practices in alternance training used in community and junior colleges and technical institutes throughout Texas. Various arrangements combining alternating periods of study and work, including apprenticeships, cooperative education, internships, clinical experience, and practicums,…

  3. The Compensated Pulsed Alternator Program - A Review

    DTIC Science & Technology

    1981-06-01

    mechanical systems, CEM-UT proposed the compensated pulsed alternator approach in January, lg7s. The basic idea behind the compulsator concept is to...compen- sated, pulsed alternator is shown in Figure 1. STATIONARY FIELD COMPULSATOR Figure 1 Rotor (armature) winding Stator (compensating) winding... Compulsator An engineering prototype compulsator was designed and fabricated under contract to Lawrence Livermore National Laboratory (LLNL) to

  4. Alternative Fuels Market and Policy Trends (Presentation)

    SciTech Connect

    Schroeder, A. N.

    2013-09-01

    Market forces and policies are increasing opportunities for alternative fuels. There is no one-size-fits-all, catch-all, silver-bullet fuel. States play a critical role in the alternative fuel market and are taking a leading role.

  5. Alternative Fuels Data Center (Fact Sheet)

    SciTech Connect

    Not Available

    2013-07-01

    Fact sheet describes the Alternative Fuels Data Center, which provides information, data, and tools to help fleets and other transportation decision makers find ways to reduce petroleum consumption through the use of alternative and renewable fuels, advanced vehicles, and other fuel-saving measures.

  6. Partnership in Urban Education: An Alternative School.

    ERIC Educational Resources Information Center

    Eriksen, Aase; Gantz, Joseph

    This book focuses on the process of implementing an alternative school within a public urban system. To identify and illustrate the problems inherent in organizing and operating an alternative school the West Philadelphia Community Free School was taken as a case study. Observations and analysis are here offered on two different levels: (1)…

  7. Alternative Education Completers: A Phenomenological Study

    ERIC Educational Resources Information Center

    Murray, Becky L.; Holt, Carleton R.

    2014-01-01

    The purpose of this study was to explore the elements of the alternative education experience significant to successful completion of the program. This phenomenological paradigm provided the framework for all aspects of the qualitative study. Students, parents, administrators, and staff members of two alternative programs in the southeast Kansas…

  8. 46 CFR 107.205 - Alternate compliance.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Alternate compliance. 107.205 Section 107.205 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS INSPECTION AND CERTIFICATION Inspection and Certification § 107.205 Alternate compliance. (a) In place of compliance with...

  9. 46 CFR 107.205 - Alternate compliance.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Alternate compliance. 107.205 Section 107.205 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS INSPECTION AND CERTIFICATION Inspection and Certification § 107.205 Alternate compliance. (a) In place of compliance with...

  10. 46 CFR 107.205 - Alternate compliance.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Alternate compliance. 107.205 Section 107.205 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS INSPECTION AND CERTIFICATION Inspection and Certification § 107.205 Alternate compliance. (a) In place of compliance with...

  11. Alternatives to Drug Abuse: Steps Toward Prevention.

    ERIC Educational Resources Information Center

    Cohen, Allan Y.

    This publication introduces and describes new efforts based on the concept of alternatives to drug abuse. The pamphlet is designed for educators, community groups, drug abuse professionals, treatment personnel, parents and young people. According to those who espouse the alternatives approach, motives for drug-taking inevitably include the need to…

  12. 40 CFR 194.6 - Alternative provisions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Alternative provisions. 194.6 Section... COMPLIANCE WITH THE 40 CFR PART 191 DISPOSAL REGULATIONS General Provisions § 194.6 Alternative provisions. The Administrator may, by rule pursuant to 5 U.S.C. 553, substitute for any of the provisions of...

  13. Complementary and Alternative Therapies for Down Syndrome

    ERIC Educational Resources Information Center

    Roizen, Nancy J.

    2005-01-01

    In their role as committed advocates, parents of children with Down syndrome have always sought alternative therapies, mainly to enhance cognitive function but also to improve their appearance. Nutritional supplements have been the most frequent type of complementary and alternative therapy used. Cell therapy, plastic surgery, hormonal therapy,…

  14. Student Perceptions of the Alternative School

    ERIC Educational Resources Information Center

    Herrington, Tina Sabrina

    2012-01-01

    Some students find it difficult to reach graduation in a regular secondary school setting, but may be successful in an alternative setting. Causes of not graduating could include high absenteeism and behavior problems, which may result in dropping out. This study sought student perceptions of an alternative program in a public school district in…

  15. Industrial Arts Curriculum Guide for Alternative Energy.

    ERIC Educational Resources Information Center

    Connecticut State Dept. of Education, Hartford. Div. of Vocational and Adult Education.

    This curriculum guide for alternative energy courses is part of a series of curriculum guides for use in the industrial arts curriculum in Connecticut. The guide contains two parts. Part 1 provides the following overview: (1) objectives of alternative energy education, including suggestions for course levels, class sizes, teaching methods, and…

  16. Alternative Maternity Services in Washington State.

    ERIC Educational Resources Information Center

    Starzyk, Patricia M.

    The nature of maternity services has changed in the past 20 years, with a movement away from traditional (physician delivery in a hospital) towards other alternative services. This study examined alternative maternity services in Washington State, which ranks eighth in the country in the use of such services. Data were collected from birth and…

  17. Alternatives to Institutionalization: A Definitive Bibliography.

    ERIC Educational Resources Information Center

    Brantley, James R., Comp.

    This bibliography catalogs all the literature in the National Criminals Justice Reference Service database on the topic of alternatives to institutionalization. The materials represented pertain to such diverse alternatives as juvenile training schools, pre-release centers, halfway houses, work-release programs, weekend sentencing, restitution,…

  18. 21 CFR 640.120 - Alternative procedures.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Alternative Procedures § 640.120... Regulations regarding blood, blood components, or blood products. Requests for such exceptions or alternatives... permission may be given orally by the Director. Oral requests and approvals must be promptly followed...

  19. Sodium Bearing Waste Processing Alternatives Analysis

    SciTech Connect

    Murphy, James Anthony; Palmer, Brent J; Perry, Keith Joseph

    2003-12-01

    A multidisciplinary team gathered to develop a BBWI recommendation to DOE-ID on the processing alternatives for the sodium bearing waste in the INTEC Tank Farm. Numerous alternatives were analyzed using a rigorous, systematic approach. The data gathered were evaluated through internal and external peer reviews for consistency and validity. Three alternatives were identified to be top performers: Risk-based Calcination, MACT to WIPP Calcination and Cesium Ion Exchange. A dual-path through early Conceptual design is recommended for MACT to WIPP Calcination and Cesium Ion Exchange since Risk-based Calcination does not require design. If calcination alternatives are not considered based on giving Type of Processing criteria significantly greater weight, the CsIX/TRUEX alternative follows CsIX in ranking. However, since CsIX/TRUEX shares common uncertainties with CsIX, reasonable backups, which follow in ranking, are the TRUEX and UNEX alternatives. Key uncertainties must be evaluated by the decision-makers to choose one final alternative. Those key uncertainties and a path forward for the technology roadmapping of these alternatives is provided.

  20. Alternative Natural Energy Sources in Building Design.

    ERIC Educational Resources Information Center

    Davis, Albert J.; Schubert, Robert P.

    This publication provides a discussion of various energy conserving building systems and design alternatives. The information presented here covers alternative space and water heating systems, and energy conserving building designs incorporating these systems and other energy conserving techniques. Besides water, wind, solar, and bio conversion…

  1. 46 CFR 283.4 - Alternate standards.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... OPERATORS DIVIDEND POLICY FOR OPERATORS RECEIVING OPERATING-DIFFERENTIAL SUBSIDY § 283.4 Alternate standards. (a) The Maritime Administrator may waive or modify any of the financial terms or requirements otherwise applicable in part 283, upon determining that other factors exist which make alternate terms...

  2. Analytical services contract reform alternatives project

    SciTech Connect

    Hunt, J.W.; Fox, M.R.; Kristofzski, J.G.; Minette, M.J.

    1995-03-23

    Westinghouse Hanford Company (WHC) was directed by the U.S. Department of Energy, Richland Operations Office (DOE-RL) to examine the feasibility of outsourcing all or part of its laboratory and analytical functions as part of a contract reform effort. The analytical services provided by WHC were found to be significantly greater than that of a typical environmental laboratory which provides sample analysis based on a simple sample in-report out model. In addition to high-volume production analysis, the work scope includes special analytical services, technical consulting, sample handling and disposition, and special material preparations. Numerous broad ranging potential contract reform alternatives were identified and categorized into seven main alternatives with associated sub-alternatives. Issues associated with each alternative varied significantly depending on the alternative. Fifteen issues were identified and described including human resources, contract, and procurement areas. Readers of this report will perhaps identify additional alternatives and/or issues. In addressing the issues, it was determined that those issues pertaining to labor relations and procurement require major policy resolutions by WHC/DOE senior management prior to being able to establish meaningful assumptions for cost/benefit analyses of the seven alternatives. Further review was therefore stopped without economic analyses or recommendation for any specific alternative. Accordingly, this report is intended to fulfill the requirements of RL Milestone AS-95-016.

  3. 7 CFR 993.29 - Alternates.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Order Regulating Handling Prune Marketing Committee § 993.29 Alternates. An alternate for a member of... event of his removal, resignation, disqualification, or death, until a successor for such...

  4. BWR Steam Dryer Alternating Stress Assessment Procedures

    SciTech Connect

    Morante, R. J.; Hambric, S. A.; Ziada, S.

    2016-12-01

    This report presents an overview of Boiling Water Reactor (BWR) steam dryer design; the fatigue cracking failures that occurred at the Quad Cities (QC) plants and their root causes; a history of BWR Extended Power Uprates (EPUs) in the USA; and a discussion of steam dryer modifications/replacements, alternating stress mechanisms on steam dryers, and structural integrity evaluations (static and alternating stress).

  5. An Examination of Alternative Instructional Methods

    ERIC Educational Resources Information Center

    Brewer, Peggy D.

    2004-01-01

    Demographic shifts, advances in technology, and changing student perceptions and expectations have influenced the development of alternative means and methods for offering and delivering traditional college courses. This study reports student perceptions of four alternatives at one university where students were asked to rate course offerings…

  6. 46 CFR 183.130 - Alternative standards.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...) ELECTRICAL INSTALLATION General Provisions § 183.130 Alternative standards. (a) A vessel, other than a high... applicable: (i) E-8, “Alternating Current (AC) Electrical Systems on Boats;” (ii) E-9, “Direct Current (DC) Electrical Systems on Boats;” and (iii) A-16, “Electrical Navigation Lights.” (b) A vessel with an...

  7. 46 CFR 183.130 - Alternative standards.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...) ELECTRICAL INSTALLATION General Provisions § 183.130 Alternative standards. (a) A vessel, other than a high... applicable: (i) E-8, “Alternating Current (AC) Electrical Systems on Boats;” (ii) E-9, “Direct Current (DC) Electrical Systems on Boats;” and (iii) A-16, “Electrical Navigation Lights.” (b) A vessel with an...

  8. Alternative Energy Lessons in Scotland

    NASA Astrophysics Data System (ADS)

    Boyle, Julie

    2010-05-01

    In Scotland the new science curriculum for pupils aged 12 to 15 shall include the following outcomes: "Using my knowledge and understanding, I can express an informed view on a national or global environmental issue;" "I have participated in constructing a model to harness a renewable source of energy and can investigate how to optimise the output;" and "I can discuss why it is important to me and to the future of the world that alternatives to fossil fuels are developed." There will be an emphasis on creating lessons that will nurture responsible citizens, improve pupil engagement and allow students to develop their team working skills. To help teachers plan lessons to address this, the Scottish Schools Equipment Research Centre and Edinburgh University made teaching materials on four renewable energy resources. This poster describes how their suggested activities on solar cells, wind turbines, hydroelectric power stations and wave power were used in science lessons with twelve year old students. After an initial class discussion based on issues related to climate change and diminishing fossil fuel supplies, a workshop activity was carried out in three stages. The students were issued with a fact sheet about one of four imaginary islands (Skisdale, Cloudy Island, Surfsville and Sun City) and they were asked to work in teams to choose the most suitable method of generating electricity for their island. Issues such as costs, where it will be sited and environmental implications were considered. They were then asked to conduct practical activities by constructing and testing models for these forms of renewable energy. To conclude, they presented their proposal to the rest of the class with reasoned explanations. The kits used in the lessons can be purchased from Anderson Scientific (sales@andersonscientific.co.uk). The solar cells were simply connected to a voltmeter. The wind and hydroelectric groups used the same basic equipment. This was made using a small water

  9. Alternative Route Graphs in Road Networks

    NASA Astrophysics Data System (ADS)

    Bader, Roland; Dees, Jonathan; Geisberger, Robert; Sanders, Peter

    Every human likes choices. But today's fast route planning algorithms usually compute just a single route between source and target. There are beginnings to compute alternative routes, but there is a gap between the intuition of humans what makes a good alternative and mathematical definitions needed for grasping these concepts algorithmically. In this paper we make several steps towards closing this gap: Based on the concept of an alternative graph that can compactly encode many alternatives, we define and motivate several attributes quantifying the quality of the alternative graph. We show that it is already NP-hard to optimize a simple objective function combining two of these attributes and therefore turn to heuristics. The combination of the refined penalty based iterative shortest path routine and the previously proposed Plateau heuristics yields best results. A user study confirms these results.

  10. Alternative energy technologies for the Caribbean islands

    SciTech Connect

    Pytlinski, J.T. )

    1992-01-01

    All islands in the Caribbean except Puerto Rico can be classified as developing islands. Of these islands, all except Trinidad and Tobago are oil importers. Uncertainties concerning uninterrupted oil supply and increasing oil prices causes economic, social and political instability and jeopardizes further development of these islands. The paper discusses the energy situation of the Caribbean islands and presents alternative energy options. Several alternative energy projects financed by local, federal and international organizations are presented. Present and future uses of alternative energy technologies are described in different islands. Barrier which handicap developing and implementing alternative energy sources in the Caribbean are discussed. The potential and possible applications of alternative energy technologies such as: solar-thermal energy, photovoltaics, wind energy, ocean thermal energy conversion (OTEC), ocean currents and tides energy, biomass, peat energy, municipal solid wastes, bioconversion, hydropower, geothermal energy, nuclear energy and energy conservation are discussed in detail as means to alleviate the energy situation in the Caribbean islands.

  11. Pharmacology of Modulators of Alternative Splicing

    PubMed Central

    Morris, Jonathan C.; Oltean, Sebastian; Donaldson, Lucy F.

    2017-01-01

    More than 95% of genes in the human genome are alternatively spliced to form multiple transcripts, often encoding proteins with differing or opposing function. The control of alternative splicing is now being elucidated, and with this comes the opportunity to develop modulators of alternative splicing that can control cellular function. A number of approaches have been taken to develop compounds that can experimentally, and sometimes clinically, affect splicing control, resulting in potential novel therapeutics. Here we develop the concepts that targeting alternative splicing can result in relatively specific pathway inhibitors/activators that result in dampening down of physiologic or pathologic processes, from changes in muscle physiology to altering angiogenesis or pain. The targets and pharmacology of some of the current inhibitors/activators of alternative splicing are demonstrated and future directions discussed. PMID:28034912

  12. Investigating alternative RNA splicing in Xenopus.

    PubMed

    Mereau, Agnès; Hardy, Serge

    2012-01-01

    Alternative splicing, the process by which distinct mature mRNAs can be produced from a single primary transcript, is a key mechanism to increase the organism complexity. The generation of alternative splicing pattern is a means to expand the proteome diversity and also to control gene expression through the regulation of mRNA abundance. Alternative splicing is therefore particularly prevalent during development and accordingly numerous splicing events are regulated in a tissue or temporal manner. To study the roles of alternative splicing during developmental processes and decipher the molecular mechanisms that underlie temporal and spatial regulation, it is important to develop in vivo whole animal studies. In this chapter, we present the advantages of using the amphibian Xenopus as a fully in vivo model to study alternative splicing and we describe the experimental procedures that can be used with Xenopus laevis embryos and oocytes to define the cis-regulatory elements and identify the associated trans-acting factors.

  13. Special Section: Complementary and Alternative Medicine (CAM):Quiz on Complementary and Alternative Medicine

    MedlinePlus

    ... Special Section CAM Quiz on Complementary and Alternative Medicine Past Issues / Winter 2009 Table of Contents For ... low back pain. True False Complementary and alternative medicine (CAM) includes: Meditation Chiropractic Use of natural products, ...

  14. Alternative Energy Development and China's Energy Future

    SciTech Connect

    Zheng, Nina; Fridley, David

    2011-06-15

    In addition to promoting energy efficiency, China has actively pursued alternative energy development as a strategy to reduce its energy demand and carbon emissions. One area of particular focus has been to raise the share of alternative energy in China’s rapidly growing electricity generation with a 2020 target of 15% share of total primary energy. Over the last ten years, China has established several major renewable energy regulations along with programs and subsidies to encourage the growth of non-fossil alternative energy including solar, wind, nuclear, hydro, geothermal and biomass power as well as biofuels and coal alternatives. This study thus seeks to examine China’s alternative energy in terms of what has and will continue to drive alternative energy development in China as well as analyze in depth the growth potential and challenges facing each specific technology. This study found that despite recent policies enabling extraordinary capacity and investment growth, alternative energy technologies face constraints and barriers to growth. For relatively new technologies that have not achieved commercialization such as concentrated solar thermal, geothermal and biomass power, China faces technological limitations to expanding the scale of installed capacity. While some alternative technologies such as hydropower and coal alternatives have been slowed by uneven and often changing market and policy support, others such as wind and solar PV have encountered physical and institutional barriers to grid integration. Lastly, all alternative energy technologies face constraints in human resources and raw material resources including land and water, with some facing supply limitations in critical elements such as uranium for nuclear, neodymium for wind and rare earth metals for advanced solar PV. In light of China’s potential for and barriers to growth, the resource and energy requirement for alternative energy technologies were modeled and scenario analysis

  15. Pass It On: Alternatively Certified Teachers' Advice to Prospective Alternate Route Educators

    ERIC Educational Resources Information Center

    Brown, Casey

    2009-01-01

    Ten alternatively certified teachers provide advice to other non-traditionally certified teachers via in-depth interviews. The alternatively certified teachers interviewed had retained their teaching positions and achieved longevity in the teaching profession. Data collection and analysis resulted in alternatively certified teachers' advice to…

  16. 77 FR 31756 - Energy Conservation Program: Alternative Efficiency Determination Methods and Alternative Rating...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-30

    ... Parts 429, 430, and 431 RIN 1904-AC46 Energy Conservation Program: Alternative Efficiency Determination Methods and Alternative Rating Methods: Public Meeting AGENCY: Office of Energy Efficiency and Renewable... proposed modifications to the regulations authorizing the use of alternative methods of determining...

  17. Do We Want the Canary to Sing? Thinking Alternatively about Alternative Education

    ERIC Educational Resources Information Center

    Swain, Amy Elizabeth

    2013-01-01

    Alternative schools give us a perspective for viewing our educational system as a whole, while also considering the message and purpose of our institutions. Who does alternative schooling serve? What is the job of alternative schooling? Hugh Cale Community School, located in eastern North Carolina, offers insight into the role and purpose of…

  18. Nearest shrunken centroids via alternative genewise shrinkages

    PubMed Central

    Choi, Byeong Yeob; Bair, Eric; Lee, Jae Won

    2017-01-01

    Nearest shrunken centroids (NSC) is a popular classification method for microarray data. NSC calculates centroids for each class and “shrinks” the centroids toward 0 using soft thresholding. Future observations are then assigned to the class with the minimum distance between the observation and the (shrunken) centroid. Under certain conditions the soft shrinkage used by NSC is equivalent to a LASSO penalty. However, this penalty can produce biased estimates when the true coefficients are large. In addition, NSC ignores the fact that multiple measures of the same gene are likely to be related to one another. We consider several alternative genewise shrinkage methods to address the aforementioned shortcomings of NSC. Three alternative penalties were considered: the smoothly clipped absolute deviation (SCAD), the adaptive LASSO (ADA), and the minimax concave penalty (MCP). We also showed that NSC can be performed in a genewise manner. Classification methods were derived for each alternative shrinkage method or alternative genewise penalty, and the performance of each new classification method was compared with that of conventional NSC on several simulated and real microarray data sets. Moreover, we applied the geometric mean approach for the alternative penalty functions. In general the alternative (genewise) penalties required fewer genes than NSC. The geometric mean of the class-specific prediction accuracies was improved, as well as the overall predictive accuracy in some cases. These results indicate that these alternative penalties should be considered when using NSC. PMID:28199352

  19. Advancing practice relating to SEA alternatives

    SciTech Connect

    González, Ainhoa; Thérivel, Riki; Fry, John; Foley, Walter

    2015-07-15

    Developing and assessing alternatives is a key and central stage to Strategic Environmental Assessment (SEA). However, research has repeatedly reported this stage as one of the most poorly undertaken aspects of the SEA process. Current practice limitations include belated consideration of reasonable alternatives, narrow scope of alternatives that often include unrealistic or retrofitted options, limited stakeholder and public involvement in their identification, assessment and selection, lack of systematic approaches to their assessment and comparison, and inadequate reporting of the ‘storyline’ on how they were identified, what the potential impacts are and why the preferred alternative was selected. These issues have resulted in objections and judicial reviews. On the positive side, a number of good practice case studies enable extraction of key lessons and formulation of a set of general recommendations to advance practice in SEA alternatives. In this paper, practical guidance on the identification and development of alternatives, their assessment and comparison, selection of the preferred option, and documentation of the process and the reasons for selection is provided and discussed to frame good practice approaches. - Highlights: • Alternatives are one of the most poorly completed aspects of Strategic Environmental Assessment. • Current practice limitations need to be addressed to enhance SEA effectiveness. • A set of recommendations are extracted from good practice case studies. • These recommendations can be applied across jurisdictions and sectors and tailored as necessary.

  20. Potential of renewable and alternative energy sources

    NASA Astrophysics Data System (ADS)

    Konovalov, V.; Pogharnitskaya, O.; Rostovshchikova, A.; Matveenko, I.

    2015-11-01

    The article deals with application potential of clean alternative renewable energy sources. By means of system analysis the forecast for consumption of electrical energy in Tomsk Oblast as well as main energy sources of existing energy system have been studied up to 2018. Engineering potential of renewable and alternative energy sources is evaluated. Besides, ranking in the order of their efficiency descending is performed. It is concluded that Tomsk Oblast has high potential of alternative and renewable energy sources, among which the most promising development perspective is implementation of gasification stations to save fuel consumed by diesel power stations as well as building wind-power plants.

  1. Crankshaft position sensing with combined starter alternator

    DOEpatents

    Brandenburg, Larry Raymond; Miller, John Michael

    2000-06-13

    A crankshaft position sensing apparatus for use with an engine (16) having a combined starter/alternator assembly (18). The crankshaft position sensing apparatus includes a tone ring (38) with a sensor (36) and bandpass filter (46), having a cylinder identification input from a camshaft sensor (48), and a gain limiter (54). The sensing apparatus mounts near the rotor (30) of the combined starter/alternator assembly (18). The filtered crankshaft position signal can then be input into a vehicle system controller (58) and an inner loop controller (60). The starter/alternator assembly (18) in combination with an internal combustion engine is particularly useful for a hybrid electric vehicle system.

  2. Innovative and Alternative Technology Assessment Manual

    SciTech Connect

    1980-02-01

    This four chapter, six appendix manual presents the procedures and methodology as well as the baseline costs and energy information necessary for the analysis and evaluation of innovative and alternative technology applications submitted for federal grant assistance under the innovative and alternative technology provisions of the Clean Water Act of 1977. The manual clarifies and interprets the intent of Congress and the Environmental Protection Agency in carrying out the mandates of the innovative and alternative provisions of the Clean Water Act of 1977. [DJE 2005

  3. Chromatin, DNA structure and alternative splicing.

    PubMed

    Nieto Moreno, Nicolás; Giono, Luciana E; Cambindo Botto, Adrián E; Muñoz, Manuel J; Kornblihtt, Alberto R

    2015-11-14

    Coupling of transcription and alternative splicing via regulation of the transcriptional elongation rate is a well-studied phenomenon. Template features that act as roadblocks for the progression of RNA polymerase II comprise histone modifications and variants, DNA-interacting proteins and chromatin compaction. These may affect alternative splicing decisions by inducing pauses or decreasing elongation rate that change the time-window for splicing regulatory sequences to be recognized. Herein we discuss the evidence supporting the influence of template structural modifications on transcription and splicing, and provide insights about possible roles of non-B DNA conformations on the regulation of alternative splicing.

  4. REACT: Alternatives to Critical Materials in Magnets

    SciTech Connect

    2012-01-01

    REACT Project: The 14 projects that comprise ARPA-E’s REACT Project, short for “Rare Earth Alternatives in Critical Technologies”, are developing cost-effective alternatives to rare earths, the naturally occurring minerals with unique magnetic properties that are used in electric vehicle (EV) motors and wind generators. The REACT projects will identify low-cost and abundant replacement materials for rare earths while encouraging existing technologies to use them more efficiently. These alternatives would facilitate the widespread use of EVs and wind power, drastically reducing the amount of greenhouse gases released into the atmosphere.

  5. Complementary and alternative therapies and SCI nursing.

    PubMed

    Oliver, N R

    2001-01-01

    Increasing numbers of individuals are experimenting with different complementary and alternative techniques and practices in their quest to improve their health status or change symptom experiences. Consumer utilization patterns are described, activities to ensure the safety and efficacy of alternative practices are reviewed, and relationships to nursing interventions and nursing responsibilities are presented. The relationship between complementary/alternative therapies and spinal cord injury (SCI) nursing practice, education, and research are described, as well as strategies for integrating these therapies into SCI nursing. The potential roles for SCI nurses and benefits to individuals with SCI are unlimited.

  6. Crankshaft position sensing with combined starter alternator

    SciTech Connect

    Brandenburg, L.R.; Miller, J.M.

    2000-06-13

    A crankshaft position sensing apparatus is described for use with an engine having a combined starter/alternator assembly. The crankshaft position sensing apparatus includes a tone ring with a sensor and bandpass filter, having a cylinder identification input from a camshaft sensor, and a gain limiter. The sensing apparatus mounts near the rotor of the combined starter/alternator assembly. The filtered crankshaft position signal can then be input into a vehicle system controller and an inner loop controller. The starter/alternator assembly in combination with an internal combustion engine is particularly useful for a hybrid electric vehicle system.

  7. Tapping the potential of alternative medicine.

    PubMed

    La Puma, J; Eiler, G

    1998-04-01

    Interest in alternative medicine is growing among healthcare consumers. Health plans and healthcare organizations may be able to improve clinical outcomes and benefit financially by providing patients with access to alternative services. Organizations that can assess their communities' particular needs, draw on interested professional staff to help develop alternative medicine programs and protocols, and study quality outcomes will stand a better chance of making such programs successful. Educating medical staff, designing a credible program, and forging strategic alliances with respected partners can help organizations create a sharply focused brand identity in the community.

  8. Alternative theories of gravity and Lorentz violation

    NASA Astrophysics Data System (ADS)

    Xu, Rui; Foster, Joshua; Kostelecky, V. Alan

    2017-01-01

    General relativity has achieved many successes, including the prediction of experimental results. However, its incompatibility with quantum theory remains an obstacle. By extending the foundational properties of general relativity, alternative theories of gravity can be constructed. In this talk, we focus on fermion couplings in the weak-gravity limit of certain alternative theories of gravity. Under suitable experimental circumstances, some of these couplings match terms appearing in the gravitational SME, which is a general framework describing violations of local Lorentz invariance. Existing limits on Lorentz violation can therefore be used to constrain certain Lorentz-invariant alternative theories of gravity.

  9. Alternative Work Schedules Increase Employee Satisfaction.

    ERIC Educational Resources Information Center

    Turney, John R.; Cohen, Stanley L.

    1983-01-01

    Facets of alternative work schedules (AWS) are discussed: importance of employee control, possible negative consequences, AWS handbook, time monitoring systems, and treatment of exceptions. AWS' effect on productivity and motivation is examined. (SK)

  10. Air Quality Dispersion Modeling - Alternative Models

    EPA Pesticide Factsheets

    Models, not listed in Appendix W, that can be used in regulatory applications with case-by-case justification to the Reviewing Authority as noted in Section 3.2, Use of Alternative Models, in Appendix W.

  11. Survey of alternative feedstocks for biodiesel production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Summarized will be results obtained from the production of biodiesel from several alternative feedstocks with promising agronomic characteristics. Such feedstocks include camelina (Camelina sativa L.), coriander (Coriandrum sativum L.), field pennycress (Thlaspi arvense L.), and meadowfoam (Limnanth...

  12. Alternating superlattice textures in driven nanomagnets

    NASA Astrophysics Data System (ADS)

    Leon, Alejandro O.; Laroze, David; Clerc, Marcel G.; Cabanas, Ana M.

    2017-03-01

    Nanomagnets driven with uniform electric currents exhibit a wide variety of spatial textures. In the present work, we investigate alternating superlattice states in nanomagnets, which are spatially periodic textures composed by several spatial modes that oscillate in time. The magnetic system is described in the continuum approach by the Landau-Lifshitz-Gilbert-Slonczewski equation, and direct numerical simulations of this model allow us to characterize the alternating patterns. As a result of this temporal oscillation, textures alternate between different shapes. In particular, we focus on two types of textures, namely a superhexagon and a square-like pattern, which are composed by six and two dominant Fourier modes, respectively. Based on an appropriate modal decomposition, we reveal that the mechanism that originates the alternating superhexagon is a homoclinic bifurcation. In addition, we show that the oscillatory square-like texture emerges through a supercritical Andronov-Hopf bifurcation.

  13. Alternative Programs and Desegregation in Flint, Michigan

    ERIC Educational Resources Information Center

    Kugler, Marianne Russell

    1978-01-01

    Discusses the results of the Flint, Michigan Board of Education's decision to include extensive development of alternative programs as part of the Quality Education/Desegregation Plan developed for the Flint schools. (Author/RK)

  14. Parallelizing alternating direction implicit solver on GPUs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We present a parallel Alternating Direction Implicit (ADI) solver on GPUs. Our implementation significantly improves existing implementations in two aspects. First, we address the scalability issue of existing Parallel Cyclic Reduction (PCR) implementations by eliminating their hardware resource con...

  15. Alternative institutional arrangements for nuclear power

    SciTech Connect

    Bussard, D.

    1980-08-01

    This paper investigates how alternative organizations of nuclear power generation would effect the regulatory environment for nuclear power production, how it would effect financial constraints on new construction, and what governmental barriers to such reorganization exist.

  16. Alternative Radioisotopes for Heat and Power Sources

    NASA Astrophysics Data System (ADS)

    Tinsley, T.; Sarsfield, M.; Rice, T.

    Production of 238Pu requires considerable facilities including a nuclear reactor and reprocessing plants that are very expensive to build and operate. Thus, a more economical alternative is very attractive to the industry. There are many alternative radioisotopes that exist but few that satisfy the criteria of performance, availability and cost to produce. Any alternative to 238Pu must exist in a chemical form that is compatible with the materials required to safely encapsulate the heat source at the high temperatures of operation and potential launch failure scenarios. The chemical form must also have suitable thermal properties to ensure maximum energy conversion efficiencies when integrated into radioisotope thermoelectric generators over the required mission durations. In addition, the radiation dose must be low enough for operators during production and not so prohibitive that excessive shielding mass is required on the space craft. This paper will focus on the preferred European alternative of 241Am, and the issues that will need to be addressed.

  17. Ear Infection Treatment: Do Alternative Therapies Work?

    MedlinePlus

    ... recommended for use in children — some have dangerous side effects or may interfere with conventional treatments. By Mayo Clinic Staff Alternative ear infection treatments abound on the internet and in books and magazines. They include chiropractic adjustments, homeopathy, herbal ...

  18. The Foreign Language Requirement: An Alternative Program.

    ERIC Educational Resources Information Center

    Demuth, Katherine A.; Smith, Nathaniel B.

    1987-01-01

    A new program at Boston University that identifies students who would have great difficulty fulfilling their foreign language requirement is described. This program offers an alternative sequence of courses designed to help these students achieve foreign language learning success. (LMO)

  19. Beating the traffic with commuting alternatives

    SciTech Connect

    1995-05-01

    This pamphlet describes how, by encouraging commuting options, local governments can help reduce air pollution, fuel consumption, and traffic congestion. Minimizing these problems makes the community more appealing to businesses, residents, and visitors and boosts the local economy. Approaches to alternative transportation are as varied as the communities devising and using them. But the critical factor is initiative from local governments, often one of communities largest employers. They can use and promote commuting alternatives among their employees. Local governments can also promote alternative transportation among other employers and the general public. They can provide information on commuting options, improve the infrastructure, and use local authority to require and reward those changes necessary to make alternative transportation a widely accepted part of community life. Best of all, local governments can lead by example and establish a template for other employers to follow.

  20. Complementary and Alternative Therapies for Chronic Constipation

    PubMed Central

    2015-01-01

    Chronic constipation, an ancient disease, is prevalent, and costly in the general population. Complementary and alternative therapies are frequently used for constipation. This review introduces various methods of complementary and alternative therapies, including acupuncture, moxibustion, massage, and herbal medicine. Efficacy, safety, influence factors, sham control design, and mechanisms of these therapies are discussed and evaluated. Acupuncture or electroacupuncture was found to be most commonly used for constipation among these complementary and alternative therapies, followed by herbal medicine. Although only a small number of clinical studies are flawless, our review of the literature seems to suggest that acupuncture or electroacupuncture and herbal medicine are effective in treating constipation, whereas findings on massage and moxibustion are inconclusive. More well-designed clinical trials are needed to improve and prove the efficacy of the complementary and alternative therapies for constipation; mechanistic studies that would lead to wide spread use and improvement of the methods are also discussed in this review. PMID:26064163