Sample records for facta est lux

  1. Involvement of Shewanella oneidensis MR-1 LuxS in Biofilm Development and Sulfur Metabolism

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Learman, Deric R.; Yi, Haakrho; Brown, Steven D.

    2009-01-05

    The role of LuxS in Shewanella oneidensis MR-1 has been examined by transcriptomic profiling, biochemical, and physiological experiments. The results indicate that a mutation in luxS alters biofilm development, not by altering quorum-sensing abilities but by disrupting the activated methyl cycle (AMC). The S. oneidensis wild type can produce a luminescence response in the AI-2 reporter strain Vibrio harveyi MM32. This luminescence response is abolished upon the deletion of luxS. The deletion of luxS also alters biofilm formations in static and flowthrough conditions. Genetic complementation restores the mutant biofilm defect, but the addition of synthetic AI-2 has no effect. Thesemore » results suggest that AI-2 is not used as a quorum-sensing signal to regulate biofilm development in S. oneidensis. Growth on various sulfur sources was examined because of the involvement of LuxS in the AMC. A mutation in luxS produced a reduced ability to grow with methionine as the sole sulfur source. Methionine is a key metabolite used in the AMC to produce a methyl source in the cell and to recycle homocysteine. These data suggest that LuxS is important to metabolizing methionine and the AMC in S. oneidensis.« less

  2. The Staphylococcus aureus autoinducer-2 synthase LuxS is regulated by Ser/Thr phosphorylation.

    PubMed

    Cluzel, Marie-Eve; Zanella-Cléon, Isabelle; Cozzone, Alain J; Fütterer, Klaus; Duclos, Bertrand; Molle, Virginie

    2010-12-01

    The Staphylococcus aureus autoinducer-2 (AI-2) producer protein LuxS is phosphorylated by the Ser/Thr kinase Stk1 at a unique position, Thr14. The enzymatic activity of the phosphorylated isoform of LuxS was abrogated compared to that of nonphosphorylated LuxS, thus providing the first evidence of an AI-2-producing enzyme regulated by phosphorylation and demonstrating that S. aureus possesses an original and specific system for controlling AI-2 synthesis.

  3. The Staphylococcus aureus Autoinducer-2 Synthase LuxS Is Regulated by Ser/Thr Phosphorylation▿

    PubMed Central

    Cluzel, Marie-Eve; Zanella-Cléon, Isabelle; Cozzone, Alain J.; Fütterer, Klaus; Duclos, Bertrand; Molle, Virginie

    2010-01-01

    The Staphylococcus aureus autoinducer-2 (AI-2) producer protein LuxS is phosphorylated by the Ser/Thr kinase Stk1 at a unique position, Thr14. The enzymatic activity of the phosphorylated isoform of LuxS was abrogated compared to that of nonphosphorylated LuxS, thus providing the first evidence of an AI-2-producing enzyme regulated by phosphorylation and demonstrating that S. aureus possesses an original and specific system for controlling AI-2 synthesis. PMID:20870760

  4. Role of luxS in Stress Tolerance and Adhesion Ability in Lactobacillus plantarum KLDS1.0391

    PubMed Central

    Jia, Fang-Fang; Zheng, Hui-Qi; Sun, Si-Rui; Pang, Xue-Hui; Liang, Yu; Shang, Jia-Cui; Zhu, Zong-Tao

    2018-01-01

    Lactobacillus plantarum, a probiotic, has a high survival rate and high colonization ability in the gastrointestinal tract. Tolerance to the gastrointestinal environment and adhesion to intestinal epithelial cells by some Lactobacillus species (excluding L. plantarum) are related to luxS/AI-2. Here, the role of luxS in tolerance to simulated digestive juice (SDJ) and adhesion to Caco-2 cells by L. plantarum KLDS1.0391 (hereafter, KLDS1.0391) was investigated. The KLDS1.0391 luxS mutant strain was constructed by homologous recombination. When luxS was deleted, acid and bile salt tolerance and survival rates in SDJ significantly decreased (p < 0.05 for all). The ability of the luxS deletion strain to adhere to Caco-2 cells was markedly lower than that of the wild-type strain (p < 0.05). The ability of the luxS mutant strain to adhere (competition, exclusion, and displacement) to Escherichia coli ATCC 25922 was significantly lower than that of the wild-type strain (p < 0.05 for all). A significant decrease was noted only in the exclusion adhesion inhibition of the luxS mutant strain to Salmonella typhimurium ATCC 14028 (p < 0.05). These results indicate that the luxS gene plays an important role in the gastrointestinal environment tolerance and adhesion ability of KLDS1.0391. PMID:29651434

  5. Inactivation of the Haemophilus ducreyi luxS gene affects the virulence of this pathogen in human subjects.

    PubMed

    Labandeira-Rey, Maria; Janowicz, Diane M; Blick, Robert J; Fortney, Kate R; Zwickl, Beth; Katz, Barry P; Spinola, Stanley M; Hansen, Eric J

    2009-08-01

    Haemophilus ducreyi 35000HP contains a homologue of the luxS gene, which encodes an enzyme that synthesizes autoinducer 2 (AI-2) in other gram-negative bacteria. H. ducreyi 35000HP produced AI-2 that functioned in a Vibrio harveyi-based reporter system. A H. ducreyi luxS mutant was constructed by insertional inactivation of the luxS gene and lost the ability to produce AI-2. Provision of the H. ducreyi luxS gene in trans partially restored AI-2 production by the mutant. The luxS mutant was compared with its parent for virulence in the human challenge model of experimental chancroid. The pustule-formation rate in 5 volunteers was 93.3% (95% confidence interval, 81.7%-99.9%) at 15 parent sites and 60.0% (95% confidence interval, 48.3%-71.7%) at 15 mutant sites (1-tailed P < .001). Thus, the luxS mutant was partially attenuated for virulence. This is the first report of AI-2 production contributing to the pathogenesis of a genital ulcer disease.

  6. Functional correlation of bacterial LuxS with their quaternary associations: interface analysis of the structure networks

    PubMed Central

    Bhattacharyya, Moitrayee; Vishveshwara, Saraswathi

    2009-01-01

    Background The genome of a wide variety of prokaryotes contains the luxS gene homologue, which encodes for the protein S-ribosylhomocysteinelyase (LuxS). This protein is responsible for the production of the quorum sensing molecule, AI-2 and has been implicated in a variety of functions such as flagellar motility, metabolic regulation, toxin production and even in pathogenicity. A high structural similarity is present in the LuxS structures determined from a few species. In this study, we have modelled the structures from several other species and have investigated their dimer interfaces. We have attempted to correlate the interface features of LuxS with the phenotypic nature of the organisms. Results The protein structure networks (PSN) are constructed and graph theoretical analysis is performed on the structures obtained from X-ray crystallography and on the modelled ones. The interfaces, which are known to contain the active site, are characterized from the PSNs of these homodimeric proteins. The key features presented by the protein interfaces are investigated for the classification of the proteins in relation to their function. From our analysis, structural interface motifs are identified for each class in our dataset, which showed distinctly different pattern at the interface of LuxS for the probiotics and some extremophiles. Our analysis also reveals potential sites of mutation and geometric patterns at the interface that was not evident from conventional sequence alignment studies. Conclusion The structure network approach employed in this study for the analysis of dimeric interfaces in LuxS has brought out certain structural details at the side-chain interaction level, which were elusive from the conventional structure comparison methods. The results from this study provide a better understanding of the relation between the luxS gene and its functional role in the prokaryotes. This study also makes it possible to explore the potential direction towards the

  7. Critical role of LuxS in the virulence of Campylobacter jejuni in a guinea pig model of abortion.

    PubMed

    Plummer, Paul; Sahin, Orhan; Burrough, Eric; Sippy, Rachel; Mou, Kathy; Rabenold, Jessica; Yaeger, Mike; Zhang, Qijing

    2012-02-01

    Previous studies on Campylobacter jejuni have demonstrated the role of LuxS in motility, cytolethal distending toxin production, agglutination, and intestinal colonization; however, its direct involvement in virulence has not been reported. In this study, we demonstrate a direct role of luxS in the virulence of C. jejuni in two different animal hosts. The IA3902 strain, a highly virulent sheep abortion strain recently described by our laboratory, along with its isogenic luxS mutant and luxS complement strains, was inoculated by the oral route into both a pregnant guinea pig virulence model and a chicken colonization model. In both cases, the IA3902 luxS mutant demonstrated a complete loss of ability to colonize the intestinal tract. In the pregnant model, the mutant also failed to induce abortion, while the wild-type strain was highly abortifacient. Genetic complementation of the luxS gene fully restored the virulent phenotype in both models. Interestingly, when the organism was inoculated into guinea pigs by the intraperitoneal route, no difference in virulence (abortion induction) was observed between the luxS mutant and the wild-type strain, suggesting that the defect in virulence following oral inoculation is likely associated with a defect in colonization and/or translocation of the organism out of the intestine. These studies provide the first direct evidence that LuxS plays an important role in the virulence of C. jejuni using an in vivo model of natural disease.

  8. Functional Analysis of luxS in Staphylococcus aureus Reveals a Role in Metabolism but Not Quorum Sensing

    PubMed Central

    Doherty, Neil; Holden, Matthew T. G.; Qazi, Saara N.; Williams, Paul; Winzer, Klaus

    2006-01-01

    The function of AI-2 in many bacteria and the physiological role of LuxS, the enzyme responsible for its production, remain matters of debate. Here, we show that in Staphylococcus aureus the luxS gene forms a monocistronic transcriptional unit under the control of a σ70-dependent promoter. The gene was transcribed throughout growth under a variety of conditions, including intracellular growth in MAC-T cells. AI-2 was produced in rich media under aerobic and anaerobic conditions, peaking during the transition to stationary phase, but was hardly detectable in a sulfur-limited defined medium. In the presence of glucose or under anaerobic conditions, cultures retained considerable AI-2 activity after entry into stationary phase. Inactivation of luxS in various S. aureus strains did not affect virulence-associated traits, such as production of hemolysins and extracellular proteases, biofilm formation, and the agr signaling system. Conversely, AI-2 production remained unchanged in an agr mutant. However, luxS mutants grown in a sulfur-limited defined medium exhibited a growth defect. When grown together with the wild type in mixed culture, luxS mutants of various S. aureus strains showed reduced ability to compete for growth under these conditions. In contrast, a complemented luxS mutant grew as well as the parent strain, suggesting that the observed growth defect was of an intracellular nature and had not been caused by either second-site mutations or the lack of a diffusible factor. However, the LuxS/AI-2 system does not appear to contribute to the overall fitness of S. aureus RN6390B during intracellular growth in epithelial cells: the wild type and a luxS mutant showed very similar growth patterns after their internalization by MAC-T cells. PMID:16585750

  9. Effect of the luxS gene on biofilm formation and antibiotic resistance by Salmonella serovar Dublin.

    PubMed

    Ju, Xiangyu; Li, Junjie; Zhu, Mengjiao; Lu, Zhaoxin; Lv, Fengxia; Zhu, Xiaoyu; Bie, Xiaomei

    2018-05-01

    Biofilms are communities of bacterial cells that serve to protect them from external adverse influences and enhance bacterial resistance to antibiotics and sanitizers. Here, we studied the regulatory effects of glucose and sodium chloride on biofilm formation in Salmonella serovar Dublin (S. Dublin). To analyze expression levels of the quorum sensing gene luxS, we created a luxS knockout mutant. Also, antimicrobial resistance, hydrophobicity and autoinducer-2 (AI-2) activity of both the wild-type (WT) and the mutant strain were investigated. Our results revealed that glucose was not essential for S. Dublin biofilm formation but had an inhibitory effect on biofilm formation when the concentration was over 0.1%. NaCl was found to be indispensable in forming biofilm, and it also exerted an inhibitory effect at high concentrations (>1.0%). Both the WT and the mutant strains displayed significant MIC growth after biofilm formation. An increase of up to 32,768 times in the resistance of S. Dublin in biofilm phonotype against antibiotic (ampicillin) compared to its planktonic phonotype was observed. However, S. Dublin luxS knockout mutant only showed slight differences compared to the WT strain in the antimicrobial tests although it displayed better biofilm-forming capacity than the WT strain. The mutant strain also exhibited higher hydrophobicity than the WT strain, which was a feature related to biofilm formation. The production of the quorum sensing autoinducer-2 (AI-2) was significantly lower in the mutant strain than in the WT strain since the LuxS enzyme, encoded by the luxS gene, plays an essential role in AI-2 synthesis. However, the limited biofilm-forming ability in the WT strain indicated AI-2 was not directly related to S. Dublin biofilm formation. Furthermore, gene expression analysis of the WT and mutant strains revealed upregulation of genes related to biofilm stress response and enhanced resistance in the luxS mutant strain, which may provide evidence for

  10. Involvement of LuxS in Aeromonas salmonicida metabolism, virulence and infection in Atlantic salmon (Salmo salar L).

    PubMed

    Meng, Lingjie; Du, Yishuai; Liu, Pengfei; Li, Xian; Liu, Ying

    2017-05-01

    Quorum sensing is a bacterial density dependent communication system, which regarded to regulate co-operative behaviors of community and mediated by extracellular signal molecules named autoinducers (AI). Among various signals, autoinducer-2 (AI-2) is believed to be the messengers inter species and produced by LuxS. For Aeromonas salmonicida (A. salmonicida), an opportunistic pathogen to many cold-water teleost, little information has been known about the function of AI-2 and LuxS. Therefore, our aim was to preliminarily clarify the function of LuxS in A. salmonicida. The consequences demonstrated that wild type A. salmonicida exhibited AI-2 activity and luxS defective mutant strain fail to produce AI-2 signals. Furthermore, it was suggested that luxS deficiency could impact bacterial morphology, surface properties and virulence dramatically. Challenge experiment showed a tendency that immune factors expressed earlier when Atlantic salmon was infected with ΔluxS strain. Overall, we hypothesis that AI-2 quorum sensing could regulate the expression of A-layer protein coding gene vapA, and then influence bacterial survival ability when suffered from attack of the host immune system. Though additional studies are warranted, our study will supply a new thinking to control the damage caused by A. salmonicida. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Establishing bacterial communities by 'word of mouth': LuxS and autoinducer 2 in biofilm development.

    PubMed

    Hardie, Kim Rachael; Heurlier, Karin

    2008-08-01

    Multicellular bacterial communities (biofilms) abound in nature, and their successful formation and survival is likely to require cell-cell communication--including quorum sensing--to co-ordinate appropriate gene expression. The only mode of quorum sensing that is shared by both Gram-positive and Gram-negative bacteria involves the production of the signalling molecule autoinducer 2 by LuxS. A survey of the current literature reveals that luxS contributes to biofilm development in some bacteria. However, inconsistencies prevent biofilm development being attributed to the production of AI2 in all cases.

  12. Elucidation of the conformational free energy landscape in H.pylori LuxS and its implications to catalysis.

    PubMed

    Bhattacharyya, Moitrayee; Vishveshwara, Saraswathi

    2010-08-12

    One of the major challenges in understanding enzyme catalysis is to identify the different conformations and their populations at detailed molecular level in response to ligand binding/environment. A detail description of the ligand induced conformational changes provides meaningful insights into the mechanism of action of enzymes and thus its function. In this study, we have explored the ligand induced conformational changes in H.pylori LuxS and the associated mechanistic features. LuxS, a dimeric protein, produces the precursor (4,5-dihydroxy-2,3-pentanedione) for autoinducer-2 production which is a signalling molecule for bacterial quorum sensing. We have performed molecular dynamics simulations on H.pylori LuxS in its various ligand bound forms and analyzed the simulation trajectories using various techniques including the structure network analysis, free energy evaluation and water dynamics at the active site. The results bring out the mechanistic details such as co-operativity and asymmetry between the two subunits, subtle changes in the conformation as a response to the binding of active and inactive forms of ligands and the population distribution of different conformations in equilibrium. These investigations have enabled us to probe the free energy landscape and identify the corresponding conformations in terms of network parameters. In addition, we have also elucidated the variations in the dynamics of water co-ordination to the Zn2+ ion in LuxS and its relation to the rigidity at the active sites. In this article, we provide details of a novel method for the identification of conformational changes in the different ligand bound states of the protein, evaluation of ligand-induced free energy changes and the biological relevance of our results in the context of LuxS structure-function. The methodology outlined here is highly generalized to illuminate the linkage between structure and function in any protein of known structure.

  13. Lack of genomic evidence of AI-2 receptors suggests a non-quorum sensing role for luxS in most bacteria

    PubMed Central

    Rezzonico, Fabio; Duffy, Brion

    2008-01-01

    Background Great excitement accompanied discoveries over the last decade in several Gram-negative and Gram-positive bacteria of the LuxS protein, which catalyzes production of the AI-2 autoinducer molecule for a second quorum sensing system (QS-2). Since the luxS gene was found to be widespread among the most diverse bacterial taxa, it was hypothesized that AI-2 may constitute the basis of a universal microbial language, a kind of bacterial Esperanto. Many of the studies published in this field have drawn a direct correlation between the occurrence of the luxS gene in a given organism and the presence and functionality of a QS-2 therein. However, rarely hathe existence of potential AI-2 receptors been examined. This is important, since it is now well recognized that LuxS also holds a central role as a metabolic enzyme in the activated methyl cycle which is responsible for the generation of S-adenosyl-L-methionine, the major methyl donor in the cell. Results In order to assess whether the role of LuxS in these bacteria is indeed related to AI-2 mediated quorum sensing we analyzed genomic databases searching for established AI-2 receptors (i.e., LuxPQ-receptor of Vibrio harveyi and Lsr ABC-transporter of Salmonella typhimurium) and other presumed QS-related proteins and compared the outcome with published results about the role of QS-2 in these organisms. An unequivocal AI-2 related behavior was restricted primarily to organisms bearing known AI-2 receptor genes, while phenotypes of luxS mutant bacteria lacking these genes could often be explained simply by assuming deficiencies in sulfur metabolism. Conclusion Genomic analysis shows that while LuxPQ is restricted to Vibrionales, the Lsr-receptor complex is mainly present in pathogenic bacteria associated with endotherms. This suggests that QS-2 may play an important role in interactions with animal hosts. In most other species, however, the role of LuxS appears to be limited to metabolism, although in a few cases

  14. Lack of genomic evidence of AI-2 receptors suggests a non-quorum sensing role for luxS in most bacteria.

    PubMed

    Rezzonico, Fabio; Duffy, Brion

    2008-09-20

    Great excitement accompanied discoveries over the last decade in several Gram-negative and Gram-positive bacteria of the LuxS protein, which catalyzes production of the AI-2 autoinducer molecule for a second quorum sensing system (QS-2). Since the luxS gene was found to be widespread among the most diverse bacterial taxa, it was hypothesized that AI-2 may constitute the basis of a universal microbial language, a kind of bacterial Esperanto. Many of the studies published in this field have drawn a direct correlation between the occurrence of the luxS gene in a given organism and the presence and functionality of a QS-2 therein. However, rarely hathe existence of potential AI-2 receptors been examined. This is important, since it is now well recognized that LuxS also holds a central role as a metabolic enzyme in the activated methyl cycle which is responsible for the generation of S-adenosyl-L-methionine, the major methyl donor in the cell. In order to assess whether the role of LuxS in these bacteria is indeed related to AI-2 mediated quorum sensing we analyzed genomic databases searching for established AI-2 receptors (i.e., LuxPQ-receptor of Vibrio harveyi and Lsr ABC-transporter of Salmonella typhimurium) and other presumed QS-related proteins and compared the outcome with published results about the role of QS-2 in these organisms. An unequivocal AI-2 related behavior was restricted primarily to organisms bearing known AI-2 receptor genes, while phenotypes of luxS mutant bacteria lacking these genes could often be explained simply by assuming deficiencies in sulfur metabolism. Genomic analysis shows that while LuxPQ is restricted to Vibrionales, the Lsr-receptor complex is mainly present in pathogenic bacteria associated with endotherms. This suggests that QS-2 may play an important role in interactions with animal hosts. In most other species, however, the role of LuxS appears to be limited to metabolism, although in a few cases the presence of yet unknown

  15. Census of solo LuxR genes in prokaryotic genomes

    PubMed Central

    Hudaiberdiev, Sanjarbek; Choudhary, Kumari S.; Vera Alvarez, Roberto; Gelencsér, Zsolt; Ligeti, Balázs; Lamba, Doriano; Pongor, Sándor

    2015-01-01

    luxR genes encode transcriptional regulators that control acyl homoserine lactone-based quorum sensing (AHL QS) in Gram negative bacteria. On the bacterial chromosome, luxR genes are usually found next or near to a luxI gene encoding the AHL signal synthase. Recently, a number of luxR genes were described that have no luxI genes in their vicinity on the chromosome. These so-called solo luxR genes may either respond to internal AHL signals produced by a non-adjacent luxI in the chromosome, or can respond to exogenous signals. Here we present a survey of solo luxR genes found in complete and draft bacterial genomes in the NCBI databases using HMMs. We found that 2698 of the 3550 luxR genes found are solos, which is an unexpectedly high number even if some of the hits may be false positives. We also found that solo LuxR sequences form distinct clusters that are different from the clusters of LuxR sequences that are part of the known luxR-luxI topological arrangements. We also found a number of cases that we termed twin luxR topologies, in which two adjacent luxR genes were in tandem or divergent orientation. Many of the luxR solo clusters were devoid of the sequence motifs characteristic of AHL binding LuxR proteins so there is room to speculate that the solos may be involved in sensing hitherto unknown signals. It was noted that only some of the LuxR clades are rich in conserved cysteine residues. Molecular modeling suggests that some of the cysteines may be involved in disulfide formation, which makes us speculate that some LuxR proteins, including some of the solos may be involved in redox regulation. PMID:25815274

  16. Census of solo LuxR genes in prokaryotic genomes.

    PubMed

    Hudaiberdiev, Sanjarbek; Choudhary, Kumari S; Vera Alvarez, Roberto; Gelencsér, Zsolt; Ligeti, Balázs; Lamba, Doriano; Pongor, Sándor

    2015-01-01

    luxR genes encode transcriptional regulators that control acyl homoserine lactone-based quorum sensing (AHL QS) in Gram negative bacteria. On the bacterial chromosome, luxR genes are usually found next or near to a luxI gene encoding the AHL signal synthase. Recently, a number of luxR genes were described that have no luxI genes in their vicinity on the chromosome. These so-called solo luxR genes may either respond to internal AHL signals produced by a non-adjacent luxI in the chromosome, or can respond to exogenous signals. Here we present a survey of solo luxR genes found in complete and draft bacterial genomes in the NCBI databases using HMMs. We found that 2698 of the 3550 luxR genes found are solos, which is an unexpectedly high number even if some of the hits may be false positives. We also found that solo LuxR sequences form distinct clusters that are different from the clusters of LuxR sequences that are part of the known luxR-luxI topological arrangements. We also found a number of cases that we termed twin luxR topologies, in which two adjacent luxR genes were in tandem or divergent orientation. Many of the luxR solo clusters were devoid of the sequence motifs characteristic of AHL binding LuxR proteins so there is room to speculate that the solos may be involved in sensing hitherto unknown signals. It was noted that only some of the LuxR clades are rich in conserved cysteine residues. Molecular modeling suggests that some of the cysteines may be involved in disulfide formation, which makes us speculate that some LuxR proteins, including some of the solos may be involved in redox regulation.

  17. The LUX experiment

    DOE PAGES

    Akerib, D. S.; Araújo, H. M.; Bai, X.; ...

    2015-03-24

    We present the status and prospects of the LUX experiment, which employs approximately 300 kg of two-phase xenon to search for WIMP dark matter interactions. The LUX detector was commissioned at the surface laboratory of the Sanford Underground Research Facility in Lead, SD, between December 2011 and February 2012 and the detector has been operating underground since January, 2013. These proceedings review the results of the commissioning run as well as the status of underground data-taking.

  18. The LUX Experiment

    NASA Astrophysics Data System (ADS)

    Akerib, D. S.; Araújo, H. M.; Bai, X.; Bailey, A. J.; Balajthy, J.; Bernard, E.; Bernstein, A.; Bradley, A.; Byram, D.; Cahn, S. B.; Carmona-Benitez, M. C.; Chan, C.; Chapman, J. J.; Chiller, A. A.; Chiller, C.; Coffey, T.; Currie, A.; de Viveiros, L.; Dobi, A.; Dobson, J.; Druszkiewicz, E.; Edwards, B.; Faham, C. H.; Fiorucci, S.; Flores, C.; Gaitskell, R. J.; Gehman, V. M.; Ghag, C.; Gibson, K. R.; Gilchriese, M. G. D.; Hall, C.; Hertel, S. A.; Horn, M.; Huang, D. Q.; Ihm, M.; Jacobsen, R. G.; Kazkaz, K.; Knoche, R.; Larsen, N. A.; Lee, C.; Lindote, A.; Lopes, M. I.; Malling, D. C.; Mannino, R.; McKinsey, D. N.; Mei, D.-M.; Mock, J.; Moongweluwan, M.; Morad, J.; Murphy, A. St. J.; Nehrkorn, C.; Nelson, H.; Neves, F.; Ott, R. A.; Pangilinan, M.; Parker, P. D.; Pease, E. K.; Pech, K.; Phelps, P.; Reichhart, L.; Shutt, T.; Silva, C.; Solovov, V. N.; Sorensen, P.; O'Sullivan, K.; Sumner, T. J.; Szydagis, M.; Taylor, D.; Tennyson, B.; Tiedt, D. R.; Tripathi, M.; Uvarov, S.; Verbus, J. R.; Walsh, N.; Webb, R.; White, J. T.; Witherell, M. S.; Wolfs, F. L. H.; Woods, M.; Zhang, C.

    We present the status and prospects of the LUX experiment, which employs approximately 300 kg of two-phase xenon to search for WIMP dark matter interactions. The LUX detector was commissioned at the surface laboratory of the Sanford Underground Research Facility in Lead, SD, between December 2011 and February 2012 and the detector has been operating underground since January, 2013. These proceedings review the results of the commissioning run as well as the status of underground data-taking through the summer of 2013.

  19. Autoinducer 2 activity in Escherichia coli culture supernatants can be actively reduced despite maintenance of an active synthase, LuxS.

    PubMed

    Hardie, Kim R; Cooksley, Clare; Green, Andrew D; Winzer, Klaus

    2003-03-01

    Production of the signalling molecule (autoinducer-2) synthesized by LuxS has been proposed to be pivotal to a universal mechanism of inter-species bacterial cell-cell communication (quorum sensing); however recently the function of LuxS has been noted to be integral to central metabolism since it contributes to the activated methyl cycle. This paper shows that when Helicobacter pylori LuxS is overproduced in Escherichia coli, it forms cross-linkable multimers. These multimers persist at comparable levels after 24 h of growth if glucose is omitted from the growth medium; however, the levels of extracellular autoinducer-2 decline (Glucose Retention of AI-2 Levels: GRAIL). Glycerol, maltose, galactose, ribose and L-arabinose could substitute for glucose, but lactose, D-arabinose, acetate, citrate and pyruvate could not. Mutations in (i). metabolic pathways (glycolytic enzymes eno, pgk, pgm; galactose epimerase; the Pta-AckA pathway), (ii). sugar transport (pts components, rbs operon, mgl, trg), and (iii). regulators involved in conventional catabolic repression (crp, cya), cAMP-independent catabolite repression (creC, fruR, rpoS,) the stringent response (relA, spoT) and the global carbon storage regulator (csrA) did not prevent GRAIL. Although the basis of GRAIL remains uncertain, it is clear that the mechanism is distinct from conventional catabolite repression. Moreover, GRAIL is not due to inactivation of the enzymic activity of LuxS, since in E. coli, LuxS contained within stationary-phase cells grown in the absence of glucose maintains its activity in vitro.

  20. Phylogenetically Novel LuxI/LuxR-Type Quorum Sensing Systems Isolated Using a Metagenomic Approach

    PubMed Central

    Nasuno, Eri; Fujita, Masaki J.; Nakatsu, Cindy H.; Kamagata, Yoichi; Hanada, Satoshi

    2012-01-01

    A great deal of research has been done to understand bacterial cell-to-cell signaling systems, but there is still a large gap in our current knowledge because the majority of microorganisms in natural environments do not have cultivated representatives. Metagenomics is one approach to identify novel quorum sensing (QS) systems from uncultured bacteria in environmental samples. In this study, fosmid metagenomic libraries were constructed from a forest soil and an activated sludge from a coke plant, and the target genes were detected using a green fluorescent protein (GFP)-based Escherichia coli biosensor strain whose fluorescence was screened by spectrophotometry. DNA sequence analysis revealed two pairs of new LuxI family N-acyl-l-homoserine lactone (AHL) synthases and LuxR family transcriptional regulators (clones N16 and N52, designated AubI/AubR and AusI/AusR, respectively). AubI and AusI each produced an identical AHL, N-dodecanoyl-l-homoserine lactone (C12-HSL), as determined by nuclear magnetic resonance (NMR) and mass spectrometry. Phylogenetic analysis based on amino acid sequences suggested that AusI/AusR was from an uncultured member of the Betaproteobacteria and AubI/AubR was very deeply branched from previously described LuxI/LuxR homologues in isolates of the Proteobacteria. The phylogenetic position of AubI/AubR indicates that they represent a QS system not acquired recently from the Proteobacteria by horizontal gene transfer but share a more ancient ancestry. We demonstrated that metagenomic screening is useful to provide further insight into the phylogenetic diversity of bacterial QS systems by describing two new LuxI/LuxR-type QS systems from uncultured bacteria. PMID:22983963

  1. Evaluation of Oxidative Metabolism in Leukocytes during Phagocytosis of Escherichia coli Carrying Genetic Constructs soxS::lux or katG::lux.

    PubMed

    Karimov, I F; Deryabin, D G; Karimova, D N; Subbotina, T Yu; Manukhov, I V

    2016-06-01

    We studied ROS generation by human peripheral blood monocytes and granulocytes during phagocytosis of Escherichia coli soxS::lux or katG::lux responding by luminescence (bioluminescence) to the development of oxidative stress. Initially high sensitivity of the bioluminescent reaction of E. coli katG::lux strain to the effects of model ROS (KO2 and H2O2) and pronounced induction of luminescence upon contact with granulocytes, whereas E. coli soxS::lux demonstrated less pronounced reaction to chemical oxidants and bioluminescence was observed primarily upon contact with monocytes. A correlation was found between quantitative characteristics of E. coli katG::lux bioluminescence and luminol-dependent chemiluminescence of leukocytes in some patients, but no dependence of this kind was noted for E. coli soxS::lux. The results can provide experimental substantiation of a new approach for evaluation of ROS production by leukocytes during phagocytosis and choosing the optimal object for these studies.

  2. The Large Underground Xenon (LUX) experiment

    DOE PAGES

    Akerib, D. S.; Bai, X.; Bedikian, S.; ...

    2012-11-29

    The Large Underground Xenon (LUX) collaboration has designed and constructed a dual-phase xenon detector, in order to conduct a search for Weakly Interacting Massive Particles (WIMPs), a leading dark matter candidate. The goal of the LUX detector is to clearly detect (or exclude) WIMPS with a spin independent cross section per nucleon of 2×10 -46 cm 2, equivalent to ~1 event/100 kg/month in the inner 100-kg fiducial volume (FV) of the 370-kg detector. The overall background goals are set to have <1 background events characterized as possible WIMPs in the FV in 300 days of running. This work describes themore » design and construction of the LUX detector.« less

  3. Cristoforetti packing TripleLux-A experiment

    NASA Image and Video Library

    2015-05-08

    ISS043E181043 (05/08/2015) --- ESA (European Space Agency) astronaut Samantha Cristoforetti prepares the TripleLux-A experiment for return on SpaceX’s Dragon cargo craft. TripleLux-A is investigating immune suppression in space as understanding such risks is essential in maintaining the health and performance of crew members during long-duration missions.

  4. Phylogenetic Analysis of the Incidence of lux Gene Horizontal Transfer in Vibrionaceae▿ †

    PubMed Central

    Urbanczyk, Henryk; Ast, Jennifer C.; Kaeding, Allison J.; Oliver, James D.; Dunlap, Paul V.

    2008-01-01

    Horizontal gene transfer (HGT) is thought to occur frequently in bacteria in nature and to play an important role in bacterial evolution, contributing to the formation of new species. To gain insight into the frequency of HGT in Vibrionaceae and its possible impact on speciation, we assessed the incidence of interspecies transfer of the lux genes (luxCDABEG), which encode proteins involved in luminescence, a distinctive phenotype. Three hundred three luminous strains, most of which were recently isolated from nature and which represent 11 Aliivibrio, Photobacterium, and Vibrio species, were screened for incongruence of phylogenies based on a representative housekeeping gene (gyrB or pyrH) and a representative lux gene (luxA). Strains exhibiting incongruence were then subjected to detailed phylogenetic analysis of horizontal transfer by using multiple housekeeping genes (gyrB, recA, and pyrH) and multiple lux genes (luxCDABEG). In nearly all cases, housekeeping gene and lux gene phylogenies were congruent, and there was no instance in which the lux genes of one luminous species had replaced the lux genes of another luminous species. Therefore, the lux genes are predominantly vertically inherited in Vibrionaceae. The few exceptions to this pattern of congruence were as follows: (i) the lux genes of the only known luminous strain of Vibrio vulnificus, VVL1 (ATCC 43382), were evolutionarily closely related to the lux genes of Vibrio harveyi; (ii) the lux genes of two luminous strains of Vibrio chagasii, 21N-12 and SB-52, were closely related to those of V. harveyi and Vibrio splendidus, respectively; (iii) the lux genes of a luminous strain of Photobacterium damselae, BT-6, were closely related to the lux genes of the lux-rib2 operon of Photobacterium leiognathi; and (iv) a strain of the luminous bacterium Photobacterium mandapamensis was found to be merodiploid for the lux genes, and the second set of lux genes was closely related to the lux genes of the lux-rib2

  5. Prevalence of LuxR- and LuxI-type quorum sensing circuits in members of the Populus deltoides microbiome

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schaefer, Amy L; Lappala, Colin; Morlen, Ryan

    2013-01-01

    We are interested in the root microbiome of the fast-growing Eastern cottonwood tree, Populus 25 deltoides. There is a large bank of bacterial isolates from P. deltoides and there are 44 draft 26 genomes of bacterial endophyte and rhizosphere isolates. As a first step in efforts to understand 27 the roles of bacterial communication and plant-bacterial signaling in P. deltoides we focused on 28 the prevalence of acyl-homoserine lactone (AHL) quorum sensing signal production and 29 reception in members of the P. deltoides microbiome. We screened 129 bacterial isolates for 30 AHL production using a broad-spectrum bioassay that responds tomore » many but not all AHLs, and 31 we queried the available genome sequences of microbiome isolates for homologs of AHL 32 synthase and receptor genes. AHL signal production was detected in 40% of 129 strains tested. 33 Positive isolates included -, - and -Proteobacteria. Members of the luxI family of AHL 34 synthases were identified in 18 of 39 Proteobacteria genomes including genomes of some 35 isolates that tested negative in the bioassay. Members of the luxR family of transcription factors, 36 that include AHL-responsive factors, were more abundant than luxI homologs. There were 72 in 37 the 39 Proteobacteria genomes. Some of the luxR homologs appear to be members of a 38 subfamily of LuxRs that respond to as yet unknown plant signals rather than bacterial AHLs. 39 Apparently, there is a substantial capacity for AHL cell-to-cell communication in Proteobacteria 40 of the P. deltoides microbiota and there are also Proteobacteria with LuxR homologs of the type 41 hypothesized to respond to plant signals or cues.« less

  6. The pkI gene encoding pyruvate kinase I links to the luxZ gene which enhances bioluminescence of the lux operon from Photobacterium leiognathi.

    PubMed

    Lin, J W; Lu, H C; Chen, H Y; Weng, S F

    1997-10-09

    Partial 3'-end nucleotide sequence of the pkI gene (GenBank accession No. AF019143) from Photobacterium leiognathi ATCC 25521 has been determined, and the encoded pyruvate kinase I is deduced. Pyruvate kinase I is the key enzyme of glycolysis, which converts phosphoenol pyruvate to pyruvate. Alignment and comparison of pyruvate kinase Is from P. leiognathi, E. coli and Salmonella typhimurium show that they are homologous. Nucleotide sequence reveals that the pkI gene is linked to the luxZ gene that enhances bioluminescence of the lux operon from P. leiognathi. The gene order of the pkI and luxZ genes is-pk1-ter-->-R&R"-luxZ-ter"-->, whereas ter is transcriptional terminator for the pkI and related genes, and R&R" is the regulatory region and ter" is transcriptional terminator for the luxZ gene. It clearly elicits that the pkI gene and luxZ gene are divided to two operons. Functional analysis confirms that the potential hairpin loop omega T is the transcriptional terminator for the pkI and related genes. It infers that the pkI and related genes are simply linked to the luxZ gene in P. leiognathi genome.

  7. Data acquisition and readout system for the LUX dark matter experiment

    DOE PAGES

    Akerib, D. S.; Bai, X.; Bedikian, S.; ...

    2011-11-28

    LUX is a two-phase (liquid/gas) xenon time projection chamber designed to detect nuclear recoils from interactions with dark matter particles. Signals from the LUX detector are processed by custom-built analog electronics which provide properly shaped signals for the trigger and data acquisition (DAQ) systems. The DAQ is comprised of commercial digitizers with firmware customized for the LUX experiment. Data acquisition systems in rare-event searches must accommodate high rate and large dynamic range during precision calibrations involving radioactive sources, while also delivering low threshold for maximum sensitivity. The LUX DAQ meets these challenges using real-time baseline sup- pression that allows formore » a maximum event acquisition rate in excess of 1.5 kHz with virtually no deadtime. This work describes the LUX DAQ and the novel acquisition techniques employed in the LUX experiment.« less

  8. Tritium calibration of the LUX dark matter experiment

    NASA Astrophysics Data System (ADS)

    Akerib, D. S.; Araújo, H. M.; Bai, X.; Bailey, A. J.; Balajthy, J.; Beltrame, P.; Bernard, E. P.; Bernstein, A.; Biesiadzinski, T. P.; Boulton, E. M.; Bradley, A.; Bramante, R.; Cahn, S. B.; Carmona-Benitez, M. C.; Chan, C.; Chapman, J. J.; Chiller, A. A.; Chiller, C.; Currie, A.; Cutter, J. E.; Davison, T. J. R.; de Viveiros, L.; Dobi, A.; Dobson, J. E. Y.; Druszkiewicz, E.; Edwards, B. N.; Faham, C. H.; Fiorucci, S.; Gaitskell, R. J.; Gehman, V. M.; Ghag, C.; Gibson, K. R.; Gilchriese, M. G. D.; Hall, C. R.; Hanhardt, M.; Haselschwardt, S. J.; Hertel, S. A.; Hogan, D. P.; Horn, M.; Huang, D. Q.; Ignarra, C. M.; Ihm, M.; Jacobsen, R. G.; Ji, W.; Kazkaz, K.; Khaitan, D.; Knoche, R.; Larsen, N. A.; Lee, C.; Lenardo, B. G.; Lesko, K. T.; Lindote, A.; Lopes, M. I.; Malling, D. C.; Manalaysay, A. G.; Mannino, R. L.; Marzioni, M. F.; McKinsey, D. N.; Mei, D.-M.; Mock, J.; Moongweluwan, M.; Morad, J. A.; Murphy, A. St. J.; Nehrkorn, C.; Nelson, H. N.; Neves, F.; O'Sullivan, K.; Oliver-Mallory, K. C.; Ott, R. A.; Palladino, K. J.; Pangilinan, M.; Pease, E. K.; Phelps, P.; Reichhart, L.; Rhyne, C.; Shaw, S.; Shutt, T. A.; Silva, C.; Solovov, V. N.; Sorensen, P.; Stephenson, S.; Sumner, T. J.; Szydagis, M.; Taylor, D. J.; Taylor, W.; Tennyson, B. P.; Terman, P. A.; Tiedt, D. R.; To, W. H.; Tripathi, M.; Tvrznikova, L.; Uvarov, S.; Verbus, J. R.; Webb, R. C.; White, J. T.; Whitis, T. J.; Witherell, M. S.; Wolfs, F. L. H.; Young, S. K.; Zhang, C.; LUX Collaboration

    2016-04-01

    We present measurements of the electron-recoil (ER) response of the LUX dark matter detector based upon 170 000 highly pure and spatially uniform tritium decays. We reconstruct the tritium energy spectrum using the combined energy model and find good agreement with expectations. We report the average charge and light yields of ER events in liquid xenon at 180 and 105 V /cm and compare the results to the NEST model. We also measure the mean charge recombination fraction and its fluctuations, and we investigate the location and width of the LUX ER band. These results provide input to a reanalysis of the LUX run 3 weakly interacting massive particle search.

  9. Tritium calibration of the LUX dark matter experiment

    DOE PAGES

    Akerib, D. S.

    2016-04-20

    Here, we present measurements of the electron-recoil (ER) response of the LUX dark matter detector based upon 170,000 highly pure and spatially uniform tritium decays. We reconstruct the tritium energy spectrum using the combined energy model and find good agreement with expectations. We report the average charge and light yields of ER events in liquid xenon at 180 and 105 V/cm and compare the results to the NEST model. We also measure the mean charge recombination fraction and its fluctuations, and we investigate the location and width of the LUX ER band. These results provide input to a reanalysis ofmore » the LUX run 3 weakly interacting massive particle search.« less

  10. Afatinib versus cisplatin-based chemotherapy for EGFR mutation-positive lung adenocarcinoma (LUX-Lung 3 and LUX-Lung 6): analysis of overall survival data from two randomised, phase 3 trials.

    PubMed

    Yang, James Chih-Hsin; Wu, Yi-Long; Schuler, Martin; Sebastian, Martin; Popat, Sanjay; Yamamoto, Nobuyuki; Zhou, Caicun; Hu, Cheng-Ping; O'Byrne, Kenneth; Feng, Jifeng; Lu, Shun; Huang, Yunchao; Geater, Sarayut L; Lee, Kye Young; Tsai, Chun-Ming; Gorbunova, Vera; Hirsh, Vera; Bennouna, Jaafar; Orlov, Sergey; Mok, Tony; Boyer, Michael; Su, Wu-Chou; Lee, Ki Hyeong; Kato, Terufumi; Massey, Dan; Shahidi, Mehdi; Zazulina, Victoria; Sequist, Lecia V

    2015-02-01

    We aimed to assess the effect of afatinib on overall survival of patients with EGFR mutation-positive lung adenocarcinoma through an analysis of data from two open-label, randomised, phase 3 trials. Previously untreated patients with EGFR mutation-positive stage IIIB or IV lung adenocarcinoma were enrolled in LUX-Lung 3 (n=345) and LUX-Lung 6 (n=364). These patients were randomly assigned in a 2:1 ratio to receive afatinib or chemotherapy (pemetrexed-cisplatin [LUX-Lung 3] or gemcitabine-cisplatin [LUX-Lung 6]), stratified by EGFR mutation (exon 19 deletion [del19], Leu858Arg, or other) and ethnic origin (LUX-Lung 3 only). We planned analyses of mature overall survival data in the intention-to-treat population after 209 (LUX-Lung 3) and 237 (LUX-Lung 6) deaths. These ongoing studies are registered with ClinicalTrials.gov, numbers NCT00949650 and NCT01121393. Median follow-up in LUX-Lung 3 was 41 months (IQR 35-44); 213 (62%) of 345 patients had died. Median follow-up in LUX-Lung 6 was 33 months (IQR 31-37); 246 (68%) of 364 patients had died. In LUX-Lung 3, median overall survival was 28.2 months (95% CI 24.6-33.6) in the afatinib group and 28.2 months (20.7-33.2) in the pemetrexed-cisplatin group (HR 0.88, 95% CI 0.66-1.17, p=0.39). In LUX-Lung 6, median overall survival was 23.1 months (95% CI 20.4-27.3) in the afatinib group and 23.5 months (18.0-25.6) in the gemcitabine-cisplatin group (HR 0.93, 95% CI 0.72-1.22, p=0.61). However, in preplanned analyses, overall survival was significantly longer for patients with del19-positive tumours in the afatinib group than in the chemotherapy group in both trials: in LUX-Lung 3, median overall survival was 33.3 months (95% CI 26.8-41.5) in the afatinib group versus 21.1 months (16.3-30.7) in the chemotherapy group (HR 0.54, 95% CI 0.36-0.79, p=0.0015); in LUX-Lung 6, it was 31.4 months (95% CI 24.2-35.3) versus 18.4 months (14.6-25.6), respectively (HR 0.64, 95% CI 0.44-0.94, p=0.023). By contrast, there were no

  11. Status of the Large Underground Xenon (LUX) Detector

    NASA Astrophysics Data System (ADS)

    Larsen, Nicole

    2012-03-01

    The LUX (Large Underground Xenon) experiment is a 350-kg xenon-based direct dark matter detection experiment consisting of a two-phase (liquid/gas) xenon time projection chamber with a 100-kg fiducial mass. This technology has many advantages, including scalability, self-shielding, the absence of any long-lived isotopes, high gamma ray stopping power, and the ability to precisely measure the charge-to-light ratio of interactions within the detector, which provides an accurate method for discriminating between electron recoils (gamma rays, beta decays) and nuclear recoils (neutrons, WIMPS) within the detector. LUX's projected sensitivity for 300 days of acquisition is a cross-section of 7 x10-46 cm^2 for a WIMP mass of 100 GeV, representing an increase of nearly an order of magnitude over previous WIMP cross-section limits. From November 2011 through February 2012, LUX was deployed in a surface laboratory at the Homestake Mine in South Dakota for its second surface run. This talk will provide an overview of the LUX design and a report on the status of the experiment after the surface run and before underground deployment.

  12. Non-native acylated homoserine lactones reveal that LuxIR quorum sensing promotes symbiont stability

    PubMed Central

    Ho, Jessica S.; Geske, Grant D.; Blackwell, Helen E.; Ruby, Edward G.

    2014-01-01

    SUMMARY Quorum sensing, a group behavior coordinated by a diffusible pheromone signal and a cognate receptor, is typical of bacteria that form symbioses with plants and animals. LuxIR-type acyl homoserine-lactone (AHL) quorum sensing is common in Gram-negative proteobacteria, and many members of this group have additional quorum-sensing networks. The bioluminescent symbiont Vibrio fischeri encodes two AHL signal synthases: AinS and LuxI. AinS-dependent quorum sensing converges with LuxI-dependent quorum sensing at the LuxR regulatory element. Both AinS- and LuxI-mediated signaling are required for efficient and persistent colonization of the squid host, Euprymna scolopes. The basis of the mutualism is symbiont bioluminescence, which is regulated by both LuxI- and AinS-dependent quorum sensing, and is essential for maintaining a colonization of the host. Here, we used chemical and genetic approaches to probe the dynamics of LuxI- and AinS-mediated regulation of bioluminescence during symbiosis. We demonstrate that both native AHLs and non-native AHL analogs can be used to non-invasively and specifically modulate induction of symbiotic bioluminescence via LuxI-dependent quorum sensing. Our data suggest that the first day of colonization, during which symbiont bioluminescence is induced by LuxIR, is a critical period that determines the stability of the V. fischeri population once symbiosis is established. PMID:24191970

  13. Light intensity of 5 or 20 lux on broiler behavior, welfare and productivity.

    PubMed

    Rault, Jean-Loup; Clark, Katie; Groves, Peter J; Cronin, Greg M

    2017-04-01

    Light intensity can influence broiler behavior, but discrepancies in the scientific literature remain. Furthermore, few studies have investigated the welfare implications induced by varying light intensity. We investigated the effects of providing 5 or 20 lux light intensity on broiler behavior, welfare and productivity. A total of 1,872 Ross 308 broilers of mixed sex were studied across 2 replicates. Treatments began on d 8 with one of 2 light intensity levels: 5 lux or 20 lux, using LED lights on a 16L:8D photoperiod with 30 min sunrise and sunset periods. Production data, behavioral activity, and plasma samples for corticosterone concentration analysis were collected weekly from 8 to 46 d of age. Eye weight was collected at 42 d of age. Leg strength was assessed at 35, 42 and 45 d of age using the latency to lie test and leg and foot conditions (foot pad dermatitis, hock burn, leg straightness) were assessed at 46 d. Live weight differed between light treatments, with broilers kept at 20 lux being lighter than broilers kept at 5 lux at 46 d of age (males: -5.1%, females: -2.8%, P < 0.0001), despite no significant differences in feed intake. However, broilers kept at 20 lux were more active during the photophase than broilers kept at 5 lux throughout the rearing period (P < 0.0001). Eye weight was also on average 5% lighter for broilers kept at 20 lux compared to 5 lux (P = 0.001). Nonetheless, there was no significant effect of light intensity on other measures of broiler welfare: mortality and culls, plasma corticosterone concentrations, or latency to lie reflective of leg strength. Hence, broilers kept at 20 lux compared to 5 lux were found to be more active, had slower growth, and had lighter eye weight, but other welfare measures reflective of biological functioning or leg health did not show significant changes. © 2016 Poultry Science Association Inc.

  14. A bioinformatic survey of distribution, conservation, and probable functions of LuxR solo regulators in bacteria.

    PubMed

    Subramoni, Sujatha; Florez Salcedo, Diana Vanessa; Suarez-Moreno, Zulma R

    2015-01-01

    LuxR solo transcriptional regulators contain both an autoinducer binding domain (ABD; N-terminal) and a DNA binding Helix-Turn-Helix domain (HTH; C-terminal), but are not associated with a cognate N-acyl homoserine lactone (AHL) synthase coding gene in the same genome. Although a few LuxR solos have been characterized, their distributions as well as their role in bacterial signal perception and other processes are poorly understood. In this study we have carried out a systematic survey of distribution of all ABD containing LuxR transcriptional regulators (QS domain LuxRs) available in the InterPro database (IPR005143), and identified those lacking a cognate AHL synthase. These LuxR solos were then analyzed regarding their taxonomical distribution, predicted functions of neighboring genes and the presence of complete AHL-QS systems in the genomes that carry them. Our analyses reveal the presence of one or multiple predicted LuxR solos in many proteobacterial genomes carrying QS domain LuxRs, some of them harboring genes for one or more AHL-QS circuits. The presence of LuxR solos in bacteria occupying diverse environments suggests potential ecological functions for these proteins beyond AHL and interkingdom signaling. Based on gene context and the conservation levels of invariant amino acids of ABD, we have classified LuxR solos into functionally meaningful groups or putative orthologs. Surprisingly, putative LuxR solos were also found in a few non-proteobacterial genomes which are not known to carry AHL-QS systems. Multiple predicted LuxR solos in the same genome appeared to have different levels of conservation of invariant amino acid residues of ABD questioning their binding to AHLs. In summary, this study provides a detailed overview of distribution of LuxR solos and their probable roles in bacteria with genome sequence information.

  15. A bioinformatic survey of distribution, conservation, and probable functions of LuxR solo regulators in bacteria

    PubMed Central

    Subramoni, Sujatha; Florez Salcedo, Diana Vanessa; Suarez-Moreno, Zulma R.

    2015-01-01

    LuxR solo transcriptional regulators contain both an autoinducer binding domain (ABD; N-terminal) and a DNA binding Helix-Turn-Helix domain (HTH; C-terminal), but are not associated with a cognate N-acyl homoserine lactone (AHL) synthase coding gene in the same genome. Although a few LuxR solos have been characterized, their distributions as well as their role in bacterial signal perception and other processes are poorly understood. In this study we have carried out a systematic survey of distribution of all ABD containing LuxR transcriptional regulators (QS domain LuxRs) available in the InterPro database (IPR005143), and identified those lacking a cognate AHL synthase. These LuxR solos were then analyzed regarding their taxonomical distribution, predicted functions of neighboring genes and the presence of complete AHL-QS systems in the genomes that carry them. Our analyses reveal the presence of one or multiple predicted LuxR solos in many proteobacterial genomes carrying QS domain LuxRs, some of them harboring genes for one or more AHL-QS circuits. The presence of LuxR solos in bacteria occupying diverse environments suggests potential ecological functions for these proteins beyond AHL and interkingdom signaling. Based on gene context and the conservation levels of invariant amino acids of ABD, we have classified LuxR solos into functionally meaningful groups or putative orthologs. Surprisingly, putative LuxR solos were also found in a few non-proteobacterial genomes which are not known to carry AHL-QS systems. Multiple predicted LuxR solos in the same genome appeared to have different levels of conservation of invariant amino acid residues of ABD questioning their binding to AHLs. In summary, this study provides a detailed overview of distribution of LuxR solos and their probable roles in bacteria with genome sequence information. PMID:25759807

  16. Monitoring xenon purity in the LUX detector with a mass spectrometry system

    NASA Astrophysics Data System (ADS)

    Balajthy, Jon; LUX Experiment Collaboration

    2015-04-01

    The LUX dark matter search experiment is a 350 kg two-phase liquid/gas xenon time projection chamber located at the 4850 ft level of the Sanford Underground Research Facility in Lead, SD. To monitor for radioactive impurities such as krypton and impurities which limit charge yield such as oxygen, LUX uses a xenon sampling system consisting of a mass spectrometer and a liquid nitrogen cold trap. The cold trap separates the gaseous impurities from a small sample of xenon and allows them to pass to the mass spectrometer for analysis. We report here on results from the LUX xenon sampling program. We also report on methods to enhance the sensitivity of the cold trap technique in preparation for the next-generation LUX-ZEPLIN experiment which will have even more stringent purity requirements.

  17. A Walk into the LuxR Regulators of Actinobacteria: Phylogenomic Distribution and Functional Diversity

    PubMed Central

    Santos, Catarina Lopes; Correia-Neves, Margarida; Moradas-Ferreira, Pedro; Mendes, Marta Vaz

    2012-01-01

    LuxR regulators are a widely studied group of bacterial helix-turn-helix (HTH) transcription factors involved in the regulation of many genes coding for important traits at an ecological and medical level. This regulatory family is particularly known by their involvement in quorum-sensing (QS) mechanisms, i.e., in the bacterial ability to communicate through the synthesis and binding of molecular signals. However, these studies have been mainly focused on Gram-negative organisms, and the presence of LuxR regulators in the Gram-positive Actinobacteria phylum is still poorly explored. In this manuscript, the presence of LuxR regulators among Actinobacteria was assayed using a domain-based strategy. A total of 991 proteins having one LuxR domain were identified in 53 genome-sequenced actinobacterial species, of which 59% had an additional domain. In most cases (53%) this domain was REC (receiver domain), suggesting that LuxR regulators in Actinobacteria may either function as single transcription factors or as part of two-component systems. The frequency, distribution and evolutionary stability of each of these sub-families of regulators was analyzed and contextualized regarding the ecological niche occupied by each organism. The results show that the presence of extra-domains in the LuxR-regulators was likely driven by a general need to physically uncouple the signal sensing from the signal transduction. Moreover, the total frequency of LuxR regulators was shown to be dependent on genetic, metabolic and ecological variables. Finally, the functional annotation of the LuxR regulators revealed that the bacterial ecological niche has biased the specialization of these proteins. In the case of pathogens, our results suggest that LuxR regulators can be involved in virulence and are therefore promising targets for future studies in the health-related biotechnology field. PMID:23056438

  18. Controlling optics contamination at the PolLux STXM

    NASA Astrophysics Data System (ADS)

    Watts, B.; Pilet, N.; Sarafimov, B.; Witte, K.; Raabe, J.

    2018-04-01

    Contamination of X-ray mirror surfaces by carbon is a common issue that can significantly degrade the optical performance of the instrument. The effects can be severe at photon energies near the carbon K-edge (ca. 300 eV), where the X-rays are strongly attenuated, but also significant at higher photon energies where the carbon coating affects the reflectivity and surface shape of the mirrors. [1] The Swiss Light Source has typically relied on in-situ plasma cleaning to control mirror contamination and the PolLux scanning transmission X-ray microscopy (STXM) beamline has also been employing further contamination reduction strategies in recent years. In particular, in 2014 we installed a 1×10‑8 mbar background pressure of O2 on the PolLux first mirror chamber. We present a history of efforts to control optical contamination at the PolLux beamline and report on the observed efficiencies of the different processes employed both for the in-vacuum optics and critical components of the frequently vented STXM experiment chamber.

  19. Krm83 calibration of the 2013 LUX dark matter search

    NASA Astrophysics Data System (ADS)

    Akerib, D. S.; Alsum, S.; Araújo, H. M.; Bai, X.; Bailey, A. J.; Balajthy, J.; Beltrame, P.; Bernard, E. P.; Bernstein, A.; Biesiadzinski, T. P.; Boulton, E. M.; Brás, P.; Byram, D.; Cahn, S. B.; Carmona-Benitez, M. C.; Chan, C.; Currie, A.; Cutter, J. E.; Davison, T. J. R.; Dobi, A.; Druszkiewicz, E.; Edwards, B. N.; Fallon, S. R.; Fan, A.; Fiorucci, S.; Gaitskell, R. J.; Genovesi, J.; Ghag, C.; Gilchriese, M. G. D.; Hall, C. R.; Hanhardt, M.; Haselschwardt, S. J.; Hertel, S. A.; Hogan, D. P.; Horn, M.; Huang, D. Q.; Ignarra, C. M.; Jacobsen, R. G.; Ji, W.; Kamdin, K.; Kazkaz, K.; Khaitan, D.; Knoche, R.; Larsen, N. A.; Lenardo, B. G.; Lesko, K. T.; Lindote, A.; Lopes, M. I.; Manalaysay, A.; Mannino, R. L.; Marzioni, M. F.; McKinsey, D. N.; Mei, D.-M.; Mock, J.; Moongweluwan, M.; Morad, J. A.; Murphy, A. St. J.; Nehrkorn, C.; Nelson, H. N.; Neves, F.; O'Sullivan, K.; Oliver-Mallory, K. C.; Palladino, K. J.; Pease, E. K.; Rhyne, C.; Shaw, S.; Shutt, T. A.; Silva, C.; Solmaz, M.; Solovov, V. N.; Sorensen, P.; Sumner, T. J.; Szydagis, M.; Taylor, D. J.; Taylor, W. C.; Tennyson, B. P.; Terman, P. A.; Tiedt, D. R.; To, W. H.; Tripathi, M.; Tvrznikova, L.; Uvarov, S.; Velan, V.; Verbus, J. R.; Webb, R. C.; White, J. T.; Whitis, T. J.; Witherell, M. S.; Wolfs, F. L. H.; Xu, J.; Yazdani, K.; Young, S. K.; Zhang, C.; LUX Collaboration

    2017-12-01

    LUX was the first dark matter experiment to use a Krm83 calibration source. In this paper, we describe the source preparation and injection. We also present several Krm83 calibration applications in the context of the 2013 LUX exposure, including the measurement of temporal and spatial variation in scintillation and charge signal amplitudes, and several methods to understand the electric field within the time projection chamber.

  20. Genotoxicity testing on the international space station: Preparatory work on the SOS-LUX test as part of the space experiment TRIPLE-LUX

    NASA Astrophysics Data System (ADS)

    Stojicic, Nevena; Walrafen, David; Baumstark-Khan, Christa; Rabbow, Elke; Rettberg, Petra; Weisshaar, Maria-Paz; Horneck, Gerda

    Harmful environmental factors - namely ionizing radiation - will continue to influence future manned space missions. The Radiation Biology Unit at the German Aerospace Center (DLR) develops cellular monitoring systems, which include bacterial and mammalian cell systems capable of recognizing DNA damage as a consequence of the presence of genotoxic conditions. Such a bioassay is the SOS-LUX test, which represents the radiobiological part of the German space experiment "Gene, immune and cellular responses to single and combined space flight conditions (TRIPLE-LUX)" which has been selected by the IDI/USRA Peer Review Panel for NASA/ESA to be performed on the International Space Station (ISS). It will supply basic information on the genotoxic response to radiation applied in microgravity. The biological end-point under investigation will depend on the bacterial SOS response brought about by genetically modified bacteria that are transformed with the pSWITCH plasmid (constructed from the plasmids pPLS-1 and pGFPuv). The luminescent/fluorescent bioassay SWITCH (SWITCH: Salmonella Weighting of Induced Toxicity Cyto/GenoTox for Human Health) as successor of the SOS-LUX test for rapid toxicity (genotoxicity and cytotoxicity) testing, makes use of two sensing and reporting systems for the two biological endpoints under investigation: the SOS-LUX test and the LAC- Fluoro test. The SWITCH plasmid carries the promoterless lux operon of Photobacterium leiognathi as reporter element under the control of the DNA-damage-dependent SOS promoter of ColD as sensor element (for genotoxicity testing) and the sequences for a hybrid protein consisting of β-galactosidase and GFPuv of Aequorea victoria as reporter element under the control of the (in Salmonella constitutively active) LAC promoter of Escherichia coli as sensor element (for cytotoxicity testing). The system has worked properly for terrestrial applications during the first experiments. Experiments using X-rays and UV radiation

  1. The LUX-Zeplin Dark Matter Detector

    NASA Astrophysics Data System (ADS)

    Mock, Jeremy; Lux-Zeplin (Lz) Collaboration

    2016-03-01

    The LUX-ZEPLIN (LZ) detector is a second generation dark matter experiment that will operate at the 4850 foot level of the Sanford Underground Research Experiment as a follow-up to the LUX detector, currently the world's most sensitive WIMP direct detection experiment. The LZ detector will contain 7 tonnes of active liquid xenon with a 5.6 tonne fiducial mass in the TPC. The TPC is surrounded by an active, instrumented, liquid-xenon ``skin'' region to veto gammas, then a layer of liquid scintillator to veto neutrons, all contained within a water shield. Modeling the detector is key to understanding the expected background, which in turn leads to a better understanding of the projected sensitivity, currently expected to be 2e-48 cm2 for a 50 GeV WIMP. I will discuss the current status of the LZ experiment as well as its projected sensitivity.

  2. LuxO controls extracellular protease, haemolytic activities and siderophore production in fish pathogen Vibrio alginolyticus.

    PubMed

    Wang, Q; Liu, Q; Ma, Y; Rui, H; Zhang, Y

    2007-11-01

    To characterize the luxO gene in fish pathogen Vibrio alginolyticus MVP01 and investigate its roles in regulation of extracellular products (ECP) and siderophore production. The luxO gene was cloned from V. alginolyticus MVP01. Genetic analysis revealed that it encoded a protein with high similarity to other LuxO homologues. The luxO in-frame deletion mutant and rpoN null mutant were constructed with suicide plasmids. We demonstrated that sole deletion in LuxO increased the secretion of extracellular protease and haemolytic products, but decreased siderophore production for V. alginolyticus MVP01. Mutants with null rpoN displayed significantly enhanced protease level and siderophore production while notable reduction in haemolytic activities of ECP. Vibrio alginolyticus harbours functional luxO gene that regulates the secretion of extracellular protease and haemolytic materials as well as siderophore production in either sigma(54) dependent or independent manners. The current study demonstrated that V. alginolyticus MVP01 produces extracellular protease and haemolytic activity material as well as siderophore, which may be characteristics of the virulence of the strain. Revelations that secretion of these products is under the regulation of LuxO and sigma(54) as well as the potential quorum sensing systems in V. alginolyticus MVP01 will expedite the understanding of vibriosis pathogenesis.

  3. Stenotrophomonas maltophilia responds to exogenous AHL signals through the LuxR solo SmoR (Smlt1839).

    PubMed

    Martínez, Paula; Huedo, Pol; Martinez-Servat, Sònia; Planell, Raquel; Ferrer-Navarro, Mario; Daura, Xavier; Yero, Daniel; Gibert, Isidre

    2015-01-01

    Quorum Sensing (QS) mediated by Acyl Homoserine Lactone (AHL) molecules are probably the most widespread and studied among Gram-negative bacteria. Canonical AHL systems are composed by a synthase (LuxI family) and a regulator element (LuxR family), whose genes are usually adjacent in the genome. However, incomplete AHL-QS machinery lacking the synthase LuxI is frequently observed in Proteobacteria, and the regulator element is then referred as LuxR solo. It has been shown that certain LuxR solos participate in interspecific communication by detecting signals produced by different organisms. In the case of Stenotrophomonas maltophilia, a preliminary genome sequence analysis revealed numerous putative luxR genes, none of them associated to a luxI gene. From these, the hypothetical LuxR solo Smlt1839, here designated SmoR, presents a conserved AHL binding domain and a helix-turn-helix DNA binding motif. Its genomic organization-adjacent to hchA gene-indicate that SmoR belongs to the new family "LuxR regulator chaperone HchA-associated." AHL-binding assays revealed that SmoR binds to AHLs in-vitro, at least to oxo-C8-homoserine lactone, and it regulates operon transcription, likely by recognizing a conserved palindromic regulatory box in the hchA upstream region. Supplementation with concentrated supernatants from Pseudomonas aeruginosa, which contain significant amounts of AHLs, promoted swarming motility in S. maltophilia. Contrarily, no swarming stimulation was observed when the P. aeruginosa supernatant was treated with the lactonase AiiA from Bacillus subtilis, confirming that AHL contributes to enhance the swarming ability of S. maltophilia. Finally, mutation of smoR resulted in a swarming alteration and an apparent insensitivity to the exogenous AHLs provided by P. aeruginosa. In conclusion, our results demonstrate that S. maltophilia senses AHLs produced by neighboring bacteria through the LuxR solo SmoR, regulating population behaviors such as swarming

  4. Results from the LUX dark matter experiment

    NASA Astrophysics Data System (ADS)

    Horn, Markus; Akerib, D. S.; Araújo, H. M.; Bai, X.; Bailey, A. J.; Balajthy, J.; Bernard, E.; Bernstein, A.; Bradley, A.; Byram, D.; Cahn, S. B.; Carmona-Benitez, M. C.; Chan, C.; Chapman, J. J.; Chiller, A. A.; Chiller, C.; Currie, A.; de Viveiros, L.; Dobi, A.; Dobson, J.; Druszkiewicz, E.; Edwards, B.; Faham, C. H.; Fiorucci, S.; Flores, C.; Gaitskell, R. J.; Gehman, V. M.; Ghag, C.; Gibson, K. R.; Gilchriese, M. G. D.; Hall, C.; Hanhardt, M.; Haselschwardt, S.; Hertel, S. A.; Huang, D. Q.; Ihm, M.; Jacobsen, R. G.; Kazkaz, K.; Knoche, R.; Larsen, N. A.; Lee, C.; Lenardo, B.; Lesko, K. T.; Lindote, A.; Lopes, M. I.; Malling, D. C.; Mannino, R.; McKinsey, D. N.; Mei, D.-M.; Mock, J.; Moongweluwan, M.; Morad, J.; Murphy, A. St. J.; Nehrkorn, C.; Nelson, H.; Neves, F.; Ott, R. A.; Pangilinan, M.; Parker, P. D.; Pease, E. K.; Pech, K.; Phelps, P.; Reichhart, L.; Shutt, T.; Silva, C.; Solovov, V. N.; Sorensen, P.; O`Sullivan, K.; Sumner, T. J.; Szydagis, M.; Taylor, D.; Tennyson, B.; Tiedt, D. R.; Tripathi, M.; Uvarov, S.; Verbus, J. R.; Walsh, N.; Webb, R.; White, J. T.; Witherell, M. S.; Wolfs, F. L. H.; Woods, M.; Zhang, C.; LUX Collaboration

    2015-06-01

    The LUX (Large Underground Xenon) experiment aims at the direct detection of dark matter particles via their collisions with xenon nuclei. The 370 kg two-phase liquid xenon time projection chamber measures simultaneously the scintillation and ionization from interactions in the target. The ratio of these two signals provides very good discrimination between potential nuclear recoil and electronic recoil signals to search for WIMP-nucleon scattering. The LUX detector operates at the Sanford Underground Research Facility (Lead, South Dakota, USA) since February 2013. First results were presented in late 2013 setting the world's most stringent limits on WIMP-nucleon scattering cross-sections over a wide range of WIMP masses. A 300 day run beginning in 2014 will further improve the sensitivity and new calibration techniques will reduce systematics for the WIMP signal search.

  5. Streptococcus gordonii LuxS/autoinducer-2 quorum-sensing system modulates the dual-species biofilm formation with Streptococcus mutans.

    PubMed

    Wang, Xiao; Li, Xiaolan; Ling, Junqi

    2017-07-01

    Dental plaques are mixed-species biofilms that are related to the development of dental caries. Streptococcus mutans (S. mutans) is an important cariogenic bacterium that forms mixed-species biofilms with Streptococcus gordonii (S. gordonii), an early colonizer of the tooth surface. The LuxS/autoinducer-2(AI-2) quorum sensing system is involved in the regulation of mixed-species biofilms, and AI-2 is proposed as a universal signal for the interaction between bacterial species. In this work, a S. gordonii luxS deficient strain was constructed to investigate the effect of the S. gordonii luxS gene on dual-species biofilm formed by S. mutans and S. gordonii. In addition, AI-2 was synthesized in vitro by incubating recombinant LuxS and Pfs enzymes of S. gordonii together. The effect of AI-2 on S. mutans single-species biofilm formation and cariogenic virulence gene expression were also assessed. The results showed that luxS disruption in S. gordonii altered dual-species biofilm formation, architecture, and composition, as well as the susceptibility to chlorhexidine. And the in vitro synthesized AI-2 had a concentration-dependent effect on S. mutans biofilm formation and virulence gene expression. These findings indicate that LuxS/AI-2 quorum-sensing system of S. gordonii plays a role in regulating the dual-species biofilm formation with S. mutans. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Kr 83 m calibration of the 2013 LUX dark matter search

    DOE PAGES

    Akerib, D. S.; Alsum, S.; Araújo, H. M.; ...

    2017-12-26

    Here, LUX was the first dark matter experiment to use a 83mKr calibration source. In this paper, we describe the source preparation and injection. We also present several 83mKr calibration applications in the context of the 2013 LUX exposure, including the measurement of temporal and spatial variation in scintillation and charge signal amplitudes, and several methods to understand the electric field within the time projection chamber.

  7. Kr 83 m calibration of the 2013 LUX dark matter search

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Akerib, D. S.; Alsum, S.; Araújo, H. M.

    Here, LUX was the first dark matter experiment to use a 83mKr calibration source. In this paper, we describe the source preparation and injection. We also present several 83mKr calibration applications in the context of the 2013 LUX exposure, including the measurement of temporal and spatial variation in scintillation and charge signal amplitudes, and several methods to understand the electric field within the time projection chamber.

  8. Radiogenic and muon-induced backgrounds in the LUX dark matter detector

    NASA Astrophysics Data System (ADS)

    Akerib, D. S.; Araújo, H. M.; Bai, X.; Bailey, A. J.; Balajthy, J.; Bernard, E.; Bernstein, A.; Bradley, A.; Byram, D.; Cahn, S. B.; Carmona-Benitez, M. C.; Chan, C.; Chapman, J. J.; Chiller, A. A.; Chiller, C.; Coffey, T.; Currie, A.; de Viveiros, L.; Dobi, A.; Dobson, J.; Druszkiewicz, E.; Edwards, B.; Faham, C. H.; Fiorucci, S.; Flores, C.; Gaitskell, R. J.; Gehman, V. M.; Ghag, C.; Gibson, K. R.; Gilchriese, M. G. D.; Hall, C.; Hertel, S. A.; Horn, M.; Huang, D. Q.; Ihm, M.; Jacobsen, R. G.; Kazkaz, K.; Knoche, R.; Larsen, N. A.; Lee, C.; Lindote, A.; Lopes, M. I.; Malling, D. C.; Mannino, R.; McKinsey, D. N.; Mei, D.-M.; Mock, J.; Moongweluwan, M.; Morad, J.; Murphy, A. St. J.; Nehrkorn, C.; Nelson, H.; Neves, F.; Ott, R. A.; Pangilinan, M.; Parker, P. D.; Pease, E. K.; Pech, K.; Phelps, P.; Reichhart, L.; Shutt, T.; Silva, C.; Solovov, V. N.; Sorensen, P.; O'Sullivan, K.; Sumner, T. J.; Szydagis, M.; Taylor, D.; Tennyson, B.; Tiedt, D. R.; Tripathi, M.; Uvarov, S.; Verbus, J. R.; Walsh, N.; Webb, R.; White, J. T.; Witherell, M. S.; Wolfs, F. L. H.; Woods, M.; Zhang, C.

    2015-03-01

    The Large Underground Xenon (LUX) dark matter experiment aims to detect rare low-energy interactions from Weakly Interacting Massive Particles (WIMPs). The radiogenic backgrounds in the LUX detector have been measured and compared with Monte Carlo simulation. Measurements of LUX high-energy data have provided direct constraints on all background sources contributing to the background model. The expected background rate from the background model for the 85.3 day WIMP search run is (2.6 ±0.2stat ±0.4sys) ×10-3 events keVee-1 kg-1day-1 in a 118 kg fiducial volume. The observed background rate is (3.6 ±0.4stat) ×10-3 events keVee-1 kg-1day-1 , consistent with model projections. The expectation for the radiogenic background in a subsequent one-year run is presented.

  9. Low-intensity blue-enriched white light (750 lux) and standard bright light (10,000 lux) are equally effective in treating SAD. A randomized controlled study.

    PubMed

    Meesters, Ybe; Dekker, Vera; Schlangen, Luc J M; Bos, Elske H; Ruiter, Martine J

    2011-01-28

    Photoreceptor cells containing melanopsin play a role in the phase-shifting effects of short-wavelength light. In a previous study, we compared the standard light treatment (SLT) of SAD with treatment using short-wavelength blue-enriched white light (BLT). Both treatments used the same illuminance (10,000 lux) and were equally highly effective. It is still possible, however, that neither the newly-discovered photoreceptor cells, nor the biological clock play a major role in the therapeutic effects of light on SAD. Alternatively, these effects may at least be partly mediated by these receptor cells, which may have become saturated as a result of the high illuminances used in the therapy. This randomized controlled study compares the effects of low-intensity BLT to those of high-intensity SLT. In a 22-day design, 22 patients suffering from a major depression with a seasonal pattern (SAD) were given light treatment (10,000 lux) for two weeks on workdays. Subjects were randomly assigned to either of the two conditions, with gender and age evenly distributed over the groups. Light treatment either consisted of 30 minutes SLT (5000 °K) with the EnergyLight® (Philips, Consumer Lifestyle) with a vertical illuminance of 10,000 lux at eye position or BLT (17,000 °K) with a vertical illuminance of 750 lux using a prototype of the EnergyLight® which emitted a higher proportion of short-wavelengths. All participants completed questionnaires concerning mood, activation and sleep quality on a daily basis. Mood and energy levels were also assessed on a weekly basis by means of the SIGH-SAD and other assessment tools. On day 22, SIGH-SAD ratings were significantly lower than on day 1 (SLT 65.2% and BLT 76.4%). On the basis of all assessments no statistically significant differences were found between the two conditions. With sample size being small, conclusions can only be preliminary. Both treatment conditions were found to be highly effective. The therapeutic effects of low

  10. In Helicobacter pylori auto-inducer-2, but not LuxS/MccAB catalysed reverse transsulphuration, regulates motility through modulation of flagellar gene transcription

    PubMed Central

    2010-01-01

    Background LuxS may function as a metabolic enzyme or as the synthase of a quorum sensing signalling molecule, auto-inducer-2 (AI-2); hence, the mechanism underlying phenotypic changes upon luxS inactivation is not always clear. In Helicobacter pylori, we have recently shown that, rather than functioning in recycling methionine as in most bacteria, LuxS (along with newly-characterised MccA and MccB), synthesises cysteine via reverse transsulphuration. In this study, we investigated whether and how LuxS controls motility of H. pylori, specifically if it has its effects via luxS-required cysteine metabolism or via AI-2 synthesis only. Results We report that disruption of luxS renders H. pylori non-motile in soft agar and by microscopy, whereas disruption of mccAHp or mccBHp (other genes in the cysteine provision pathway) does not, implying that the lost phenotype is not due to disrupted cysteine provision. The motility defect of the ΔluxSHp mutant was complemented genetically by luxSHp and also by addition of in vitro synthesised AI-2 or 4, 5-dihydroxy-2, 3-pentanedione (DPD, the precursor of AI-2). In contrast, exogenously added cysteine could not restore motility to the ΔluxSHp mutant, confirming that AI-2 synthesis, but not the metabolic effect of LuxS was important. Microscopy showed reduced number and length of flagella in the ΔluxSHp mutant. Immunoblotting identified decreased levels of FlaA and FlgE but not FlaB in the ΔluxSHp mutant, and RT-PCR showed that the expression of flaA, flgE, motA, motB, flhA and fliI but not flaB was reduced. Addition of DPD but not cysteine to the ΔluxSHp mutant restored flagellar gene transcription, and the number and length of flagella. Conclusions Our data show that as well as being a metabolic enzyme, H. pylori LuxS has an alternative role in regulation of motility by modulating flagellar transcripts and flagellar biosynthesis through production of the signalling molecule AI-2. PMID:20691071

  11. Discovering and visualizing indirect associations between biomedical concepts

    PubMed Central

    Tsuruoka, Yoshimasa; Miwa, Makoto; Hamamoto, Kaisei; Tsujii, Jun'ichi; Ananiadou, Sophia

    2011-01-01

    Motivation: Discovering useful associations between biomedical concepts has been one of the main goals in biomedical text-mining, and understanding their biomedical contexts is crucial in the discovery process. Hence, we need a text-mining system that helps users explore various types of (possibly hidden) associations in an easy and comprehensible manner. Results: This article describes FACTA+, a real-time text-mining system for finding and visualizing indirect associations between biomedical concepts from MEDLINE abstracts. The system can be used as a text search engine like PubMed with additional features to help users discover and visualize indirect associations between important biomedical concepts such as genes, diseases and chemical compounds. FACTA+ inherits all functionality from its predecessor, FACTA, and extends it by incorporating three new features: (i) detecting biomolecular events in text using a machine learning model, (ii) discovering hidden associations using co-occurrence statistics between concepts, and (iii) visualizing associations to improve the interpretability of the output. To the best of our knowledge, FACTA+ is the first real-time web application that offers the functionality of finding concepts involving biomolecular events and visualizing indirect associations of concepts with both their categories and importance. Availability: FACTA+ is available as a web application at http://refine1-nactem.mc.man.ac.uk/facta/, and its visualizer is available at http://refine1-nactem.mc.man.ac.uk/facta-visualizer/. Contact: tsuruoka@jaist.ac.jp PMID:21685059

  12. Deducing receptor signaling parameters from in vivo analysis: LuxN/AI-1 quorum sensing in Vibrio harveyi

    PubMed Central

    Swem, Lee R.; Swem, Danielle L.; Wingreen, Ned S.; Bassler, Bonnie L.

    2008-01-01

    Summary Quorum sensing, a process of bacterial cell-cell communication, relies on production, detection, and response to autoinducer signaling molecules. Here we focus on LuxN, a nine transmembrane domain protein from Vibrio harveyi, and the founding example of membrane-bound receptors for acyl-homoserine lactone (AHL) autoinducers. Previously, nothing was known about signal recognition by membrane-bound AHL receptors. We used mutagenesis and suppressor analyses to identify the AHL-binding domain of LuxN, and discovered LuxN mutants that confer decreased and increased AHL sensitivity. Our analysis of dose-response curves of multiple LuxN mutants pins these inverse phenotypes on quantifiable opposing shifts in the free-energy bias of LuxN for its kinase and phosphatase states. To extract signaling parameters, we exploited a strong LuxN antagonist, one of fifteen small-molecule antagonists we identified. We find that quorum-sensing-mediated communication can be manipulated positively and negatively to control bacterial behavior, and that signaling parameters can be deduced from in vivo data. PMID:18692469

  13. The influences of LuxX in Escherichia coli biofilm formation and improving teacher quality through the Bio-Bus Program

    NASA Astrophysics Data System (ADS)

    Robbins, Chandan Morris

    The objectives of this work are: (1) to agarose-stabilize fragile biofilms for quantitative structure analysis; (2) to understand the influences of LuxS on biofilm formation; (3) to improve teacher quality by preparing Georgia's middle school science teachers to integrate inquiry-based, hands-on research modules in the classroom. Quantitative digital image analysis demonstrated the effectiveness of the agarose stabilization technique for generating reproducible measurements of three dimensional biofilm structure. The described method will also benefit researchers who transport their flow cell-cultivated biofilms to a core facility for imaging. AI-2-dependent and independent effects of LuxS on biofilm-related phenotypes were revealed, suggesting that LuxS is a versatile enzyme, possessing multiple functions in E. coli ecology that could assist E. coli in adapting to diverse conditions. Overall, the work presented in this dissertation supported the concept that QS, biofilm formation, and cell adhesion are largely related. Additionally, through this project, teachers enhanced content knowledge and confidence levels, mastered innovative teaching strategies and integrated inquiry-based, inter-disciplinary, hands-on activities in the classroom. As a result, student learning was enhanced, and Georgia's students are better equipped to become tomorrow's leaders. INDEX WORDS: Biofilm, Escherichia coli, Quorum sensing, LuxS, Autoinducer-2, Microbial ecology

  14. Measurement of Yields and Fluctuations using Background and Calibration Data from the LUX Detector

    NASA Astrophysics Data System (ADS)

    Pease, Evan; LUX Collaboration

    2016-03-01

    The Large Underground Xenon (LUX) detector is a 350-kg liquid xenon (LXe) time-projection chamber designed for the direct detection of weakly-interacting massive particles (WIMPs), a leading dark matter candidate. LUX operates on the 4850-foot level of the Sanford Underground Research Facility in Lead, SD. Monoenergetic electronic recoil (ER) peaks in the WIMP search and calibration data from the first underground science run of the LUX detector have been used to measure ER light and charge yields in LXe between 5.2 keV and 662 keV. The energy resolution of the LUX detector at these energies will also be presented. Recombination fluctuations are observed to follow a linear dependence on the number of ions for the energies in this study, and this dependence is consistent with low-energy measurements made with a tritium beta source in the LUX detector. Using these results and additional measurements of the recoil bands from tritium and D-D neutron calibrations, I will compare recombination fluctuations in LXe response to electronic and nuclear recoils. The presenter is supported by the U.S. Department of Energy, Office of Science Graduate Student Research (SCGSR) program. The SCGSR program is administered by the Oak Ridge Institute for Science and Education for the DOE under contract DE-AC05-06OR23100.

  15. Radon-related Backgrounds in the LUX Dark Matter Search

    NASA Astrophysics Data System (ADS)

    Bradley, A.; Akerib, D. S.; Araújo, H. M.; Bai, X.; Bailey, A. J.; Balajthy, J.; Bernard, E.; Bernstein, A.; Byram, D.; Cahn, S. B.; Carmona-Benitez, M. C.; Chan, C.; Chapman, J. J.; Chiller, A. A.; Chiller, C.; Coffey, T.; Currie, A.; de Viveiros, L.; Dobi, A.; Dobson, J.; Druszkiewicz, E.; Edwards, B.; Faham, C. H.; Fiorucci, S.; Flores, C.; Gaitskell, R. J.; Gehman, V. M.; Ghag, C.; Gibson, K. R.; Gilchriese, M. G. D.; Hall, C.; Hertel, S. A.; Horn, M.; Huang, D. Q.; Ihm, M.; Jacobsen, R. G.; Kazkaz, K.; Knoche, R.; Larsen, N. A.; Lee, C.; Lindote, A.; Lopes, M. I.; Malling, D. C.; Mannino, R.; McKinsey, D. N.; Mei, D.-M.; Mock, J.; Moongweluwan, M.; Morad, J.; Murphy, A. St. J.; Nehrkorn, C.; Nelson, H.; Neves, F.; Ott, R. A.; Pangilinan, M.; Parker, P. D.; Pease, E. K.; Pech, K.; Phelps, P.; Reichhart, L.; Shutt, T.; Silva, C.; Solovov, V. N.; Sorensen, P.; O'Sullivan, K.; Sumner, T. J.; Szydagis, M.; Taylor, D.; Tennyson, B.; Tiedt, D. R.; Tripathi, M.; Uvarov, S.; Verbus, J. R.; Walsh, N.; Webb, R.; White, J. T.; Witherell, M. S.; Wolfs, F. L. H.; Woods, M.; Zhang, C.

    The LUX detector is currently in operation at the Davis Campus at the 4850' level of the Sanford Underground Research Facility (SURF) in Lead, SD to directly search for WIMP dark matter. Knowing the type and rate of backgrounds is critical in a rare, low energy event search, and LUX was designed, constructed, and deployed to mitigate backgrounds, both internal and external. An important internal background are decays of radon and its daughters. These consist of alpha decays, which are easily tagged and are a tracer of certain backgrounds, and beta decays, some of which are not as readily tagged and present a background for the WIMP search. We report on studies of alpha decay and discuss implications for the WIMP search.

  16. Radon-related backgrounds in the LUX dark matter search

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bradley, A.; Akerib, D. S.; Araújo, H. M.

    The LUX detector is currently in operation at the Davis Campus at the 4850’ level of the Sanford Underground Research Facility (SURF) in Lead, SD to directly search for WIMP dark matter. Knowing the type and rate of backgrounds is critical in a rare, low energy event search, and LUX was designed, constructed, and deployed to mitigate backgrounds, both internal and external. An important internal background are decays of radon and its daughters. These consist of alpha decays, which are easily tagged and are a tracer of certain backgrounds, and beta decays, some of which are not as readily taggedmore » and present a background for the WIMP search. We report on studies of alpha decay and discuss implications for the WIMP search.« less

  17. Radon-related backgrounds in the LUX dark matter search

    DOE PAGES

    Bradley, A.; Akerib, D. S.; Araújo, H. M.; ...

    2015-01-01

    The LUX detector is currently in operation at the Davis Campus at the 4850’ level of the Sanford Underground Research Facility (SURF) in Lead, SD to directly search for WIMP dark matter. Knowing the type and rate of backgrounds is critical in a rare, low energy event search, and LUX was designed, constructed, and deployed to mitigate backgrounds, both internal and external. An important internal background are decays of radon and its daughters. These consist of alpha decays, which are easily tagged and are a tracer of certain backgrounds, and beta decays, some of which are not as readily taggedmore » and present a background for the WIMP search. We report on studies of alpha decay and discuss implications for the WIMP search.« less

  18. The AstraLux Large M-dwarf Multiplicity Survey

    NASA Astrophysics Data System (ADS)

    Janson, Markus; Hormuth, Felix; Bergfors, Carolina; Brandner, Wolfgang; Hippler, Stefan; Daemgen, Sebastian; Kudryavtseva, Natalia; Schmalzl, Eva; Schnupp, Carolin; Henning, Thomas

    2012-07-01

    We present the results of an extensive high-resolution imaging survey of M-dwarf multiplicity using the Lucky Imaging technique. The survey made use of the AstraLux Norte camera at the Calar Alto 2.2 m telescope and the AstraLux Sur camera at the ESO New Technology Telescope in order to cover nearly the full sky. In total, 761 stars were observed (701 M-type and 60 late K-type), among which 182 new and 37 previously known companions were detected in 205 systems. Most of the targets have been observed during two or more epochs, and could be confirmed as physical companions through common proper motion, often with orbital motion being confirmed in addition. After accounting for various bias effects, we find a total M-dwarf multiplicity fraction of 27% ± 3% within the AstraLux detection range of 0farcs08-6'' (semimajor axes of ~3-227 AU at a median distance of 30 pc). We examine various statistical multiplicity properties within the sample, such as the trend of multiplicity fraction with stellar mass and the semimajor axis distribution. The results indicate that M-dwarfs are largely consistent with constituting an intermediate step in a continuous distribution from higher-mass stars down to brown dwarfs. Along with other observational results in the literature, this provides further indications that stars and brown dwarfs may share a common formation mechanism, rather than being distinct populations. Based on observations collected at the European Southern Observatory, Chile, under observing programs 081.C-0314(A), 082.C-0053(A), and 084.C-0812(A), and on observations collected at the Centro Astronómico Hispano Alemán (CAHA) at Calar Alto, operated jointly by the Max-Planck Institute for Astronomy and the Instituto de Astrofísica de Andalucía (CSIC).

  19. January 2018 report CAMS BeNeLux

    NASA Astrophysics Data System (ADS)

    Roggemans, Paul

    2018-02-01

    A summary of the activity of the CAMS BeNeLux network during the month January 2018 is presented. This month was characterized by exceptional poor weather, lowest amount of sunshine since January 1935 during daylight, mostly overcast during the night. Thanks to the dedication of the network team still 11986 meteors were recorded, 4859 of which proved multiple station, or 41%. In total 1878 orbits were collected during this month.

  20. Decrease in fMRI brain activation during working memory performed after sleeping under 10 lux light.

    PubMed

    Kang, Seung-Gul; Yoon, Ho-Kyoung; Cho, Chul-Hyun; Kwon, Soonwook; Kang, June; Park, Young-Min; Lee, Eunil; Kim, Leen; Lee, Heon-Jeong

    2016-11-09

    The aim of this study was to investigate the effect of exposure to dim light at night (dLAN) when sleeping on functional brain activation during a working-memory tasks. We conducted the brain functional magnetic resonance imaging (fMRI) analysis on 20 healthy male subjects. All participants slept in a polysomnography laboratory without light exposure on the first and second nights and under a dim-light condition of either 5 or 10 lux on the third night. The fMRI scanning was conducted during n-back tasks after second and third nights. Statistical parametric maps revealed less activation in the right inferior frontal gyrus (IFG) after exposure to 10-lux light. The brain activity in the right and left IFG areas decreased more during the 2-back task than during the 1- or 0-back task in the 10-lux group. The exposure to 5-lux light had no significant effect on brain activities. The exposure to dLAN might influence the brain function which is related to the cognition.

  1. Phylogenetic analysis of the lux operon distinguishes two evolutionarily distinct clades of Photobacterium leiognathi.

    PubMed

    Ast, Jennifer C; Dunlap, Paul V

    2004-05-01

    The luminous marine bacterium Photobacterium mandapamensis was synonymized several years ago with Photobacterium leiognathi based on a high degree of phenotypic and genetic similarity. To test the possibility that P. leiognathi as now formulated, however, actually contains two distinct bacterial groups reflecting the earlier identification of P. mandapamensis and P. leiognathi as separate species, we compared P. leiognathi strains isolated from light-organ symbiosis with leiognathid fishes (i.e., ATCC 25521(T), ATCC 25587, lequu.1.1 and lleuc.1.1) with strains from seawater originally described as P. mandapamensis and later synonymized as P. leiognathi (i.e., ATCC 27561(T) and ATCC 33981) and certain strains initially identified as P. leiognathi (i.e., PL-721, PL-741, 554). Analysis of the 16S rRNA and gyrB genes did not resolve distinct clades, affirming a close relationship among these strains. However, strains ATCC 27561(T), ATCC 33981, PL-721, PL-741 and 554 were found to bear a luxF gene in the lux operon ( luxABFE), whereas ATCC 25521(T), ATCC 25587, lequu.1.1 and lleuc.1.1 lack this gene ( luxABE). Phylogenetic analysis of the luxAB(F)E region confirmed this distinction. Furthermore, ATCC 27561(T), ATCC 33981, PL-721, PL-741 and 554 all produced a higher level of luminescence on high-salt medium, as previously described for PL-721, whereas ATCC 25521(T), ATCC 25587, lequu.1.1 and lleuc.1.1 all produced a higher level of luminescence on low-salt medium, a characteristic of P. leiognathi from leiognathid fish light organs. These results demonstrate that P. leiognathi contains two evolutionarily and phenotypically distinct clades, P. leiognathi subsp. leiognathi (strains ATCC 25521(T), ATCC 25587, lequu.1.1 and lleuc.1.1), and P. leiognathi subsp. mandapamensis (strains ATCC 27561(T), ATCC 33981, PL-721, PL-741 and 554).

  2. Ex Vivo Bioluminescence Imaging of Late Gestation Ewes Following Intra-uterine Inoculation With Lux-modified Escherichia coli

    USDA-ARS?s Scientific Manuscript database

    Our objectives were to develop an ovine model for Escherichia coli-induced preterm delivery, and monitor E. coli (lux modified for photonic detection) invasion of the fetal environment—ewes (124 ± 18 d of gestation) received intrauterine inoculations using E. coli-lux as follows: control (n = 5), 1....

  3. First Results from the LUX Dark Matter Experiment at the Sanford Underground Research Facility

    NASA Astrophysics Data System (ADS)

    Akerib, D. S.; Araújo, H. M.; Bai, X.; Bailey, A. J.; Balajthy, J.; Bedikian, S.; Bernard, E.; Bernstein, A.; Bolozdynya, A.; Bradley, A.; Byram, D.; Cahn, S. B.; Carmona-Benitez, M. C.; Chan, C.; Chapman, J. J.; Chiller, A. A.; Chiller, C.; Clark, K.; Coffey, T.; Currie, A.; Curioni, A.; Dazeley, S.; de Viveiros, L.; Dobi, A.; Dobson, J.; Dragowsky, E. M.; Druszkiewicz, E.; Edwards, B.; Faham, C. H.; Fiorucci, S.; Flores, C.; Gaitskell, R. J.; Gehman, V. M.; Ghag, C.; Gibson, K. R.; Gilchriese, M. G. D.; Hall, C.; Hanhardt, M.; Hertel, S. A.; Horn, M.; Huang, D. Q.; Ihm, M.; Jacobsen, R. G.; Kastens, L.; Kazkaz, K.; Knoche, R.; Kyre, S.; Lander, R.; Larsen, N. A.; Lee, C.; Leonard, D. S.; Lesko, K. T.; Lindote, A.; Lopes, M. I.; Lyashenko, A.; Malling, D. C.; Mannino, R.; McKinsey, D. N.; Mei, D.-M.; Mock, J.; Moongweluwan, M.; Morad, J.; Morii, M.; Murphy, A. St. J.; Nehrkorn, C.; Nelson, H.; Neves, F.; Nikkel, J. A.; Ott, R. A.; Pangilinan, M.; Parker, P. D.; Pease, E. K.; Pech, K.; Phelps, P.; Reichhart, L.; Shutt, T.; Silva, C.; Skulski, W.; Sofka, C. J.; Solovov, V. N.; Sorensen, P.; Stiegler, T.; O'Sullivan, K.; Sumner, T. J.; Svoboda, R.; Sweany, M.; Szydagis, M.; Taylor, D.; Tennyson, B.; Tiedt, D. R.; Tripathi, M.; Uvarov, S.; Verbus, J. R.; Walsh, N.; Webb, R.; White, J. T.; White, D.; Witherell, M. S.; Wlasenko, M.; Wolfs, F. L. H.; Woods, M.; Zhang, C.; LUX Collaboration

    2014-03-01

    The Large Underground Xenon (LUX) experiment is a dual-phase xenon time-projection chamber operating at the Sanford Underground Research Facility (Lead, South Dakota). The LUX cryostat was filled for the first time in the underground laboratory in February 2013. We report results of the first WIMP search data set, taken during the period from April to August 2013, presenting the analysis of 85.3 live days of data with a fiducial volume of 118 kg. A profile-likelihood analysis technique shows our data to be consistent with the background-only hypothesis, allowing 90% confidence limits to be set on spin-independent WIMP-nucleon elastic scattering with a minimum upper limit on the cross section of 7.6×10-46 cm2 at a WIMP mass of 33 GeV/c2. We find that the LUX data are in disagreement with low-mass WIMP signal interpretations of the results from several recent direct detection experiments.

  4. First results from the LUX dark matter experiment at the Sanford underground research facility.

    PubMed

    Akerib, D S; Araújo, H M; Bai, X; Bailey, A J; Balajthy, J; Bedikian, S; Bernard, E; Bernstein, A; Bolozdynya, A; Bradley, A; Byram, D; Cahn, S B; Carmona-Benitez, M C; Chan, C; Chapman, J J; Chiller, A A; Chiller, C; Clark, K; Coffey, T; Currie, A; Curioni, A; Dazeley, S; de Viveiros, L; Dobi, A; Dobson, J; Dragowsky, E M; Druszkiewicz, E; Edwards, B; Faham, C H; Fiorucci, S; Flores, C; Gaitskell, R J; Gehman, V M; Ghag, C; Gibson, K R; Gilchriese, M G D; Hall, C; Hanhardt, M; Hertel, S A; Horn, M; Huang, D Q; Ihm, M; Jacobsen, R G; Kastens, L; Kazkaz, K; Knoche, R; Kyre, S; Lander, R; Larsen, N A; Lee, C; Leonard, D S; Lesko, K T; Lindote, A; Lopes, M I; Lyashenko, A; Malling, D C; Mannino, R; McKinsey, D N; Mei, D-M; Mock, J; Moongweluwan, M; Morad, J; Morii, M; Murphy, A St J; Nehrkorn, C; Nelson, H; Neves, F; Nikkel, J A; Ott, R A; Pangilinan, M; Parker, P D; Pease, E K; Pech, K; Phelps, P; Reichhart, L; Shutt, T; Silva, C; Skulski, W; Sofka, C J; Solovov, V N; Sorensen, P; Stiegler, T; O'Sullivan, K; Sumner, T J; Svoboda, R; Sweany, M; Szydagis, M; Taylor, D; Tennyson, B; Tiedt, D R; Tripathi, M; Uvarov, S; Verbus, J R; Walsh, N; Webb, R; White, J T; White, D; Witherell, M S; Wlasenko, M; Wolfs, F L H; Woods, M; Zhang, C

    2014-03-07

    The Large Underground Xenon (LUX) experiment is a dual-phase xenon time-projection chamber operating at the Sanford Underground Research Facility (Lead, South Dakota). The LUX cryostat was filled for the first time in the underground laboratory in February 2013. We report results of the first WIMP search data set, taken during the period from April to August 2013, presenting the analysis of 85.3 live days of data with a fiducial volume of 118 kg. A profile-likelihood analysis technique shows our data to be consistent with the background-only hypothesis, allowing 90% confidence limits to be set on spin-independent WIMP-nucleon elastic scattering with a minimum upper limit on the cross section of 7.6 × 10(-46) cm(2) at a WIMP mass of 33 GeV/c(2). We find that the LUX data are in disagreement with low-mass WIMP signal interpretations of the results from several recent direct detection experiments.

  5. The LUX experiment - trigger and data acquisition systems

    NASA Astrophysics Data System (ADS)

    Druszkiewicz, Eryk

    2013-04-01

    The Large Underground Xenon (LUX) detector is a two-phase xenon time projection chamber designed to detect interactions of dark matter particles with the xenon nuclei. Signals from the detector PMTs are processed by custom-built analog electronics which provide properly shaped signals for the trigger and data acquisition (DAQ) systems. During calibrations, both systems must be able to handle high rates and have large dynamic ranges; during dark matter searches, maximum sensitivity requires low thresholds. The trigger system uses eight-channel 64-MHz digitizers (DDC-8) connected to a Trigger Builder (TB). The FPGA cores on the digitizers perform real-time pulse identification (discriminating between S1 and S2-like signals) and event localization. The TB uses hit patterns, hit maps, and maximum response detection to make trigger decisions, which are reached within few microseconds after the occurrence of an event of interest. The DAQ system is comprised of commercial digitizers with customized firmware. Its real-time baseline suppression allows for a maximum event acquisition rate in excess of 1.5 kHz, which results in virtually no deadtime. The performance of the trigger and DAQ systems during the commissioning runs of LUX will be discussed.

  6. Circadian Behavioral Study: LED vs Cool White Fluorescent - 0.1, 1, 10, 40, 80 lux. Part 2

    NASA Technical Reports Server (NTRS)

    Holley, Daniel C.; Syrkin, N.; Mele, G.

    2000-01-01

    Currently, the light source most commonly used in animal habitat lighting is cool white fluorescent (CWF) light. It was the objective of this study to evaluate a novel LED light source for use in animal habitat lighting by comparing its effectiveness to CWF light in producing and maintaining a normal circadian entrainment. The LED and CWF lights had similar spectral power distributions. Sprague-Dawley rats (175-350 g) were kept individually in metabolic cages, under a strict lighting control: 4 days of acclimation at 12:12 LD, 14 days of 12:12 LD, 14 days of 24:0 LD (free-run), and finally 12:12 LD. Food and water were provided ad libitum. Three behavioral parameters were monitored continuously: gross locomotor activity, drinking, and feeding. Combined mean free run periods (tau) were (mean +/- SEM): 24.6 +/- 0.1 and 24.7 +/- 0.2 at 0.1 lux, 25.5 +/- 0.1 and 25.7 +/- 0.1 at 1.0 lux, 25.3 +/- 0.2 and 25.4 +/- 0.2 at 10 lux, 25.8 +/- 0.1 and 25.9 +/- 0.1 at 40 lux, and 25.9 +/- 0.1 and 25.9 +/- 0.1 at 80 lux, CWF and LED respectively. ANOVA found a significant effect (p < 0.05) due to light level, but no difference in tau between rats exposed to constant CWF light and rats exposed to constant LED light. This study has shown that LED light can produce the same entrainment pattern as a conventional CWT light at similar intensities (0.1, 1, 10, 40, and 80 lux). LED light sources may be a suitable replacement for conventional light sources used in animal habitat lighting while providing many mechanical and economical advantages.

  7. Coordination of the Arc Regulatory System and Pheromone-Mediated Positive Feedback in Controlling the Vibrio fischeri lux Operon

    PubMed Central

    Septer, Alecia N.; Stabb, Eric V.

    2012-01-01

    Bacterial pheromone signaling is often governed both by environmentally responsive regulators and by positive feedback. This regulatory combination has the potential to coordinate a group response among distinct subpopulations that perceive key environmental stimuli differently. We have explored the interplay between an environmentally responsive regulator and pheromone-mediated positive feedback in intercellular signaling by Vibrio fischeri ES114, a bioluminescent bacterium that colonizes the squid Euprymna scolopes. Bioluminescence in ES114 is controlled in part by N-(3-oxohexanoyl)-L-homoserine lactone (3OC6), a pheromone produced by LuxI that together with LuxR activates transcription of the luxICDABEG operon, initiating a positive feedback loop and inducing luminescence. The lux operon is also regulated by environmentally responsive regulators, including the redox-responsive ArcA/ArcB system, which directly represses lux in culture. Here we show that inactivating arcA leads to increased 3OC6 accumulation to initiate positive feedback. In the absence of positive feedback, arcA-mediated control of luminescence was only ∼2-fold, but luxI-dependent positive feedback contributed more than 100 fold to the net induction of luminescence in the arcA mutant. Consistent with this overriding importance of positive feedback, 3OC6 produced by the arcA mutant induced luminescence in nearby wild-type cells, overcoming their ArcA repression of lux. Similarly, we found that artificially inducing ArcA could effectively repress luminescence before, but not after, positive feedback was initiated. Finally, we show that 3OC6 produced by a subpopulation of symbiotic cells can induce luminescence in other cells co-colonizing the host. Our results suggest that even transient loss of ArcA-mediated regulation in a sub-population of cells can induce luminescence in a wider community. Moreover, they indicate that 3OC6 can communicate information about both cell density and the state of

  8. Individual and Combined Roles of the Master Regulators AphA and LuxR in Control of the Vibrio harveyi Quorum-Sensing Regulon

    PubMed Central

    van Kessel, Julia C.; Rutherford, Steven T.; Shao, Yi; Utria, Alan F.

    2013-01-01

    Bacteria use a chemical communication process called quorum sensing to control transitions between individual and group behaviors. In the Vibrio harveyi quorum-sensing circuit, two master transcription factors, AphA and LuxR, coordinate the quorum-sensing response. Here we show that AphA regulates 167 genes, LuxR regulates 625 genes, and they coregulate 77 genes. LuxR strongly controls genes at both low cell density and high cell density, suggesting that it is the major quorum-sensing regulator. In contrast, AphA is absent at high cell density and acts to fine-tune quorum-sensing gene expression at low cell density. We examined two loci as case studies of coregulation by AphA and LuxR. First, AphA and LuxR directly regulate expression of the genes encoding the quorum-regulatory small RNAs Qrr2, Qrr3, and Qrr4, the consequence of which is a specifically timed transition between the individual and the group life-styles. Second, AphA and LuxR repress type III secretion system genes but at different times and to different extents. The consequence of this regulation is that type III secretion is restricted to a peak at mid-cell density. Thus, the asymmetric production of AphA and LuxR coupled with differences in their strengths and timing of target gene regulation generate a precise temporal pattern of gene expression. PMID:23204455

  9. Detection of E. coli O157:H7 with a reporter phage containing the luxCDABE cassette

    USDA-ARS?s Scientific Manuscript database

    Bacteriophage and reporter phage are used for typing and/or detection of pathogens. The temperate tailed phage fV10 has been utilized for phage-typing E. coli O157:H7. By modifying fV10 to transduce kanamycin resistance and the a luxCDABE cassette, we developed a reporter bacteriophage (fV10-lux) p...

  10. Sensitometric properties of Agfa Dentus OrthoLux, Agfa Dentus ST8G, and Kodak Ektavision panoramic radiographic film.

    PubMed

    Wakoh, M; Nishikawa, K; Kobayashi, N; Farman, A G; Kuroyanagi, K

    2001-02-01

    The purpose of this study was to compare the sensitometric properties of and visualization of anatomical structures with Agfa OrthoLux green-sensitive panoramic radiographic film, Agfa ST8G green sensitive panoramic radiographic film, and Kodak Ektavision green-sensitive panoramic radiographic film used in combination with an Agfa Ortho Regular 400 imaging screen, Kodak Ektavision imaging screen, and Kodak Lanex Regular imaging screen. The density response and resolution of panoramic radiographic film/intensifying screen combinations was evaluated by means of Hunter and Driffield curves, modulation transfer functions, and noise-equivalent number of quanta. Image clarity of selected anatomical structures was rated independently by 6 oral and maxillofacial radiologists. The ISO speed for the Agfa OrthoLux panoramic radiographic film combinations was the fastest, and the ISO speed for the Kodak Ektavision green-sensitive panoramic radiographic film combinations was the slowest. The average gradient for the Agfa ST8G systems was relatively steep in comparison with those for the other film/screen combinations. The modulation transfer functions for the Kodak Ektavision film were higher than those for the other films, irrespective of the screen combination used, and those for Agfa OrthoLux film were slightly higher than those for Agfa ST8G film. The noise-equivalent number of quanta for the Agfa ST8G film/screen combinations was lower than those for the other film/screen combinations. The noise-equivalent number of quanta for the Kodak Ektavision film/screen combinations was well within the high-frequency range, whereas Agfa OrthoLux combined with either the Kodak Ektavision imaging screen or the Kodak Lanex Regular imaging screen produced a noise-equivalent number of quanta similar to those of the Kodak Ektavision film/screen combinations in the low-frequency range. Agfa OrthoLux was perceived to provide clearer images of the selected anatomical details than Agfa ST8G

  11. 49 CFR Table 1 of Subpart B to... - Minimum Coefficient of Retroreflection (RA) (in Candela/Lux/Meter2) Requirement for...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Minimum Coefficient of Retroreflection (RA) (in Candela/Lux/Meter2) Requirement for Retroreflective Sheeting (Minimum Photometric Performance Requirements... Retroreflection (RA) (in Candela/Lux/Meter2) Requirement for Retroreflective Sheeting (Minimum Photometric...

  12. Bifidobacterium breve IPLA20005 affects in vitro the expression of hly and luxS genes, related to the virulence of Listeria monocytogenes Lm23.

    PubMed

    Rios-Covian, David; Nogacka, Alicja; Salazar, Nuria; Hernández-Barranco, A M; Cuesta, Isabel; Gueimonde, Miguel; de Los Reyes Gavilán, Clara G

    2018-03-01

    Mechanistic features that characterize the interaction and inhibition of the food-borne pathogen Listeria monocytogenes by members of the genus Bifidobacterium still remain unclear. In the present work, we tried to shed light on the influence that co-cultivation of L. monocytogenes with Bifidobacterium breve may exert on both microorganisms and on virulence of the pathogen. Production of acetate and lactate was measured by gas chromatography and high-performance liquid chromatography, respectively; bacterial counts were obtained by plate count; gene expression was determined by RT-qPCR; and haemolytic activity was analyzed against goat erythrocytes. We found slightly but significantly lower final counts of Listeria and Bifidobacterium (p < 0.05) and lower haemolytic efficiency in L. monocytogenes cells from cocultures than in those from monocultures. In contrast, the hly and luxS genes, which code for the cytolysin listeriolysin O and participate in biofilm formation, respectively, were overexpressed when L. monocytogenes was grown in coculture. This indicates that the presence of Bifidobacterium is able to modify the gene expression and haemolytic activity of L. monocytogenes when both microorganisms grow together.

  13. Detection of the Light Organ Symbiont, Vibrio fischeri, in Hawaiian Seawater by Using lux Gene Probes.

    PubMed

    Lee, K H; Ruby, E G

    1992-03-01

    Symbiotic bacteria that inhabit the light-emitting organ of the Hawaiian squid Euprymna scolopes are distinctive from typical Vibrio fischeri organisms in that they are not visibly luminous when grown in laboratory culture. Therefore, the abundance of these bacteria in seawater samples cannot be estimated simply by identifying them among luminous colonies that arise on nutrient agar plates. Instead, we have used luxR and polymerase chain reaction generated luxA gene probes to identify both luminous and non-visibly luminous V. fischeri colonies by DNA-DNA hybridization. The probes were specific, hybridizing at least 50 to 100 times more strongly to immobilized DNAs from V. fischeri strains than to those of pure cultures of other related species. Thus, even non-visibly luminous V. fischeri colonies could be identified among colonies obtained from natural seawater samples by their probe-positive reaction. Bacteria in seawater samples, obtained either within or distant from squid habitats, were collected on membrane filters and incubated until colonies appeared. The filters were then observed for visibly luminous V. fischeri colonies and hybridized with the lux gene probes to determine the number of total V. fischeri colonies (both luminous and non-visibly luminous). We detected no significant differences in the abundance of luminous V. fischeri CFU in any of the water samples observed (luxA and luxR gene probes were species specific and gave a reliable estimate of the number of culturable V. fischeri colonies in natural water samples.

  14. The Influences of LuxX in "Escherichia Coli" Biofilm Formation and Improving Teacher Quality through the Bio-Bus Program

    ERIC Educational Resources Information Center

    Robbins, Chandan Morris

    2012-01-01

    The objectives of this work are: (1) to agarose-stabilize fragile biofilms for quantitative structure analysis; (2) to understand the influences of LuxS on biofilm formation; (3) to improve teacher quality by preparing Georgia's middle school science teachers to integrate inquiry-based, hands-on research modules in the classroom. Quantitative…

  15. XocR, a LuxR solo required for virulence in Xanthomonas oryzae pv. oryzicola.

    PubMed

    Xu, Huiyong; Zhao, Yancun; Qian, Guoliang; Liu, Fengquan

    2015-01-01

    Xanthomonas oryzae pv. oryzicola (Xoc) causes bacterial leaf streak (BLS) in rice, a serious bacterial disease of rice in Asia and parts of Africa. The virulence mechanisms of Xoc are not entirely clear and control measures for BLS are poorly developed. The solo LuxR proteins are widespread and shown to be involved in virulence in some plant associated bacteria (PAB). Here, we have cloned and characterized a PAB LuxR solo from Xoc, named as XocR. Mutation of xocR almost completely impaired the virulence ability of Xoc on host rice, but did not alter the ability to trigger HR (hypersensitive response, a programmed cell death) on non-host (plant) tobacco, suggesting the diversity of function of xocR in host and non-host plants. We also provide evidence to show that xocR is involved in the regulation of growth-independent cell motility in response to a yet-to-be-identified rice signal, as mutation of xocR impaired cell swimming motility of wild-type Rs105 in the presence but not absence of rice macerate. We further found that xocR regulated the transcription of two characterized virulence-associated genes (recN and trpE) in the presence of rice macerate. The promoter regions of recN and trpE possessed a potential binding motif (an imperfect pip box-like element) of XocR, raising the possibility that XocR might directly bind the promoter regions of these two genes to regulate their transcriptional activity. Our studies add a new member of PAB LuxR solos and also provide new insights into the role of PAB LuxR solo in the virulence of Xanthomonas species.

  16. Limits on Spin-Dependent WIMP-Nucleon Cross Section Obtained from the Complete LUX Exposure

    NASA Astrophysics Data System (ADS)

    Akerib, D. S.; Alsum, S.; Araújo, H. M.; Bai, X.; Bailey, A. J.; Balajthy, J.; Beltrame, P.; Bernard, E. P.; Bernstein, A.; Biesiadzinski, T. P.; Boulton, E. M.; Brás, P.; Byram, D.; Cahn, S. B.; Carmona-Benitez, M. C.; Chan, C.; Chiller, A. A.; Chiller, C.; Currie, A.; Cutter, J. E.; Davison, T. J. R.; Dobi, A.; Dobson, J. E. Y.; Druszkiewicz, E.; Edwards, B. N.; Faham, C. H.; Fallon, S. R.; Fiorucci, S.; Gaitskell, R. J.; Gehman, V. M.; Ghag, C.; Gilchriese, M. G. D.; Hall, C. R.; Hanhardt, M.; Haselschwardt, S. J.; Hertel, S. A.; Hogan, D. P.; Horn, M.; Huang, D. Q.; Ignarra, C. M.; Jacobsen, R. G.; Ji, W.; Kamdin, K.; Kazkaz, K.; Khaitan, D.; Knoche, R.; Larsen, N. A.; Lee, C.; Lenardo, B. G.; Lesko, K. T.; Lindote, A.; Lopes, M. I.; Manalaysay, A.; Mannino, R. L.; Marzioni, M. F.; McKinsey, D. N.; Mei, D.-M.; Mock, J.; Moongweluwan, M.; Morad, J. A.; Murphy, A. St. J.; Nehrkorn, C.; Nelson, H. N.; Neves, F.; O'Sullivan, K.; Oliver-Mallory, K. C.; Palladino, K. J.; Pease, E. K.; Reichhart, L.; Rhyne, C.; Shaw, S.; Shutt, T. A.; Silva, C.; Solmaz, M.; Solovov, V. N.; Sorensen, P.; Stephenson, S.; Sumner, T. J.; Szydagis, M.; Taylor, D. J.; Taylor, W. C.; Tennyson, B. P.; Terman, P. A.; Tiedt, D. R.; To, W. H.; Tripathi, M.; Tvrznikova, L.; Uvarov, S.; Velan, V.; Verbus, J. R.; Webb, R. C.; White, J. T.; Whitis, T. J.; Witherell, M. S.; Wolfs, F. L. H.; Xu, J.; Yazdani, K.; Young, S. K.; Zhang, C.; LUX Collaboration

    2017-06-01

    We present experimental constraints on the spin-dependent WIMP-nucleon elastic cross sections from the total 129.5 kg yr exposure acquired by the Large Underground Xenon experiment (LUX), operating at the Sanford Underground Research Facility in Lead, South Dakota (USA). A profile likelihood ratio analysis allows 90% C.L. upper limits to be set on the WIMP-neutron (WIMP-proton) cross section of σn=1.6 ×10-41 cm2 (σp=5 ×10-40 cm2 ) at 35 GeV c-2 , almost a sixfold improvement over the previous LUX spin-dependent results. The spin-dependent WIMP-neutron limit is the most sensitive constraint to date.

  17. Liquid-purity monitor for the LUX-ZEPLIN dark matter search

    NASA Astrophysics Data System (ADS)

    Manalaysay, Aaron; Lux-Zeplin Collaboration

    2016-03-01

    The LUX-ZEPLIN (LZ) experiment will be the first liquid-xenon (LXe) dark matter search to feature a multi-tonne fiducial target. Drawing on the lessons learned in the LUX and ZEPLIN experiments, this next step will probe dark-matter candidates with unprecedented sensitivity. As these LXe detectors have grown larger, so too has the distance over which ionization electrons (from particle interactions) must be drifted through the liquid. Because of this, even minute levels of electronegative impurities can significantly attenuate the ionization signal, and must therefore be closely monitored. I will present the concept of a liquid-purity monitor which uses new and novel techniques, including state-of-the-art UV LEDs and low-work-function materials, and will measure levels of impurities in LZ's liquid circulation line in real time. This device will provide vital supplemental data to the roughly weekly in-situ purity measurements carried out within the detector's active volume, will greatly improve the resolution of the ionization channel in this detector, and will yield instant feedback in response to changing detector conditions.

  18. Results from a Search for Dark Matter in the Complete LUX Exposure

    NASA Astrophysics Data System (ADS)

    Akerib, D. S.; Alsum, S.; Araújo, H. M.; Bai, X.; Bailey, A. J.; Balajthy, J.; Beltrame, P.; Bernard, E. P.; Bernstein, A.; Biesiadzinski, T. P.; Boulton, E. M.; Bramante, R.; Brás, P.; Byram, D.; Cahn, S. B.; Carmona-Benitez, M. C.; Chan, C.; Chiller, A. A.; Chiller, C.; Currie, A.; Cutter, J. E.; Davison, T. J. R.; Dobi, A.; Dobson, J. E. Y.; Druszkiewicz, E.; Edwards, B. N.; Faham, C. H.; Fiorucci, S.; Gaitskell, R. J.; Gehman, V. M.; Ghag, C.; Gibson, K. R.; Gilchriese, M. G. D.; Hall, C. R.; Hanhardt, M.; Haselschwardt, S. J.; Hertel, S. A.; Hogan, D. P.; Horn, M.; Huang, D. Q.; Ignarra, C. M.; Ihm, M.; Jacobsen, R. G.; Ji, W.; Kamdin, K.; Kazkaz, K.; Khaitan, D.; Knoche, R.; Larsen, N. A.; Lee, C.; Lenardo, B. G.; Lesko, K. T.; Lindote, A.; Lopes, M. I.; Manalaysay, A.; Mannino, R. L.; Marzioni, M. F.; McKinsey, D. N.; Mei, D.-M.; Mock, J.; Moongweluwan, M.; Morad, J. A.; Murphy, A. St. J.; Nehrkorn, C.; Nelson, H. N.; Neves, F.; O'Sullivan, K.; Oliver-Mallory, K. C.; Palladino, K. J.; Pease, E. K.; Phelps, P.; Reichhart, L.; Rhyne, C.; Shaw, S.; Shutt, T. A.; Silva, C.; Solmaz, M.; Solovov, V. N.; Sorensen, P.; Stephenson, S.; Sumner, T. J.; Szydagis, M.; Taylor, D. J.; Taylor, W. C.; Tennyson, B. P.; Terman, P. A.; Tiedt, D. R.; To, W. H.; Tripathi, M.; Tvrznikova, L.; Uvarov, S.; Verbus, J. R.; Webb, R. C.; White, J. T.; Whitis, T. J.; Witherell, M. S.; Wolfs, F. L. H.; Xu, J.; Yazdani, K.; Young, S. K.; Zhang, C.; LUX Collaboration

    2017-01-01

    We report constraints on spin-independent weakly interacting massive particle (WIMP)-nucleon scattering using a 3.35 ×1 04 kg day exposure of the Large Underground Xenon (LUX) experiment. A dual-phase xenon time projection chamber with 250 kg of active mass is operated at the Sanford Underground Research Facility under Lead, South Dakota (USA). With roughly fourfold improvement in sensitivity for high WIMP masses relative to our previous results, this search yields no evidence of WIMP nuclear recoils. At a WIMP mass of 50 GeV c-2 , WIMP-nucleon spin-independent cross sections above 2.2 ×10-46 cm2 are excluded at the 90% confidence level. When combined with the previously reported LUX exposure, this exclusion strengthens to 1.1 ×10-46 cm2 at 50 GeV c-2 .

  19. Detection of the Light Organ Symbiont, Vibrio fischeri, in Hawaiian Seawater by Using lux Gene Probes †

    PubMed Central

    Lee, Kyu-Ho; Ruby, Edward G.

    1992-01-01

    Symbiotic bacteria that inhabit the light-emitting organ of the Hawaiian squid Euprymna scolopes are distinctive from typical Vibrio fischeri organisms in that they are not visibly luminous when grown in laboratory culture. Therefore, the abundance of these bacteria in seawater samples cannot be estimated simply by identifying them among luminous colonies that arise on nutrient agar plates. Instead, we have used luxR and polymerase chain reaction generated luxA gene probes to identify both luminous and non-visibly luminous V. fischeri colonies by DNA-DNA hybridization. The probes were specific, hybridizing at least 50 to 100 times more strongly to immobilized DNAs from V. fischeri strains than to those of pure cultures of other related species. Thus, even non-visibly luminous V. fischeri colonies could be identified among colonies obtained from natural seawater samples by their probe-positive reaction. Bacteria in seawater samples, obtained either within or distant from squid habitats, were collected on membrane filters and incubated until colonies appeared. The filters were then observed for visibly luminous V. fischeri colonies and hybridized with the lux gene probes to determine the number of total V. fischeri colonies (both luminous and non-visibly luminous). We detected no significant differences in the abundance of luminous V. fischeri CFU in any of the water samples observed (≤1 to 3 CFU/100 ml). However, probe-positive colonies of V. fischeri (up to 900 CFU/100 ml) were found only in seawater collected from within the natural habitats of the squids. A number of criteria were used to confirm that these probe-positive strains were indistinguishable from symbiotic V. fischeri. Therefore, the luxA and luxR gene probes were species specific and gave a reliable estimate of the number of culturable V. fischeri colonies in natural water samples. Images PMID:16348678

  20. The LuxS/AI-2 Quorum-Sensing System of Streptococcus pneumoniae Is Required to Cause Disease, and to Regulate Virulence- and Metabolism-Related Genes in a Rat Model of Middle Ear Infection.

    PubMed

    Yadav, Mukesh K; Vidal, Jorge E; Go, Yoon Y; Kim, Shin H; Chae, Sung-Won; Song, Jae-Jun

    2018-01-01

    Objective: Streptococcus pneumoniae colonizes the nasopharynx of children, and from nasopharynx it could migrate to the middle ear and causes acute otitis media (AOM). During colonization and AOM, the pneumococcus forms biofilms. In vitro biofilm formation requires a functional LuxS/AI-2 quorum-sensing system. We investigated the role of LuxS/AI-2 signaling in pneumococcal middle ear infection, and identified the genes that are regulated by LuxS/AI-2 during pneumococcal biofilm formation. Methods: Streptococcus pneumoniae D39 wild-type and an isogenic D39Δ luxS strain were utilized to evaluate in vitro biofilm formation, and in vivo colonization and epithelial damage using a microtiter plate assay and a rat model of pneumococcal middle ear infection, respectively. Biofilm structures and colonization and epithelial damage were evaluated at the ultrastructural level by scanning electron microscopy and confocal microscopy. Microarrays were used to investigate the global genes that were regulated by LuxS/AI-2 during biofilm formation. Results: The biofilm biomass and density of D39Δ luxS were significantly ( p < 0.05) lower than those of D39 wild-type. SEM and confocal microscopy revealed that D39Δ luxS formed thin biofilms in vitro compared with D39 wild-type. The in vivo model of middle ear infection showed that D39Δ luxS resulted in ~60% less ( p < 0.05) bacterial colonization than the wild-type. SEM analysis of the rat middle ears revealed dense biofilm-like cell debris deposited on the cilia in wild-type D39-infected rats. However, little cell debris was deposited in the middle ears of the D39Δ luxS -inoculated rats, and the cilia were visible. cDNA-microarray analysis revealed 117 differentially expressed genes in D39Δ luxS compared with D39 wild-type. Among the 66 genes encoding putative proteins and previously characterized proteins, 60 were significantly downregulated, whereas 6 were upregulated. Functional annotation revealed that genes involved in DNA

  1. Evaluation of the quality of semi-insulating CdTe for radiation detectors by measurement of lux-ampere characteristics

    NASA Astrophysics Data System (ADS)

    Franc, J.; Kubát, J.; Grill, R.; Dědič, V.; Hlídek, P.; Moravec, P.; Belas, E.

    2011-05-01

    Accumulation of space charge on deep levels represents one of the major problems in fabrication of semi-insulating CdTe and CdZnTe X-ray and gamma-ray detectors, because it influences the applied electric field and can even result in a complete breakdown of the field in part of the sample (polarization and dead layer formation). The goal of the study was to evaluate possibilities of localization of areas of potential space charge accumulation in as grown crystals by steady state measurement of lux-ampere characteristics. All measurements were done at room temperature using He-Ne laser. Voltage was applied parallel to the direction of light propagation in the range 10-100 V. It was observed that all lux-ampere characteristics are sub-linear. Screening effects caused by space charge accumulated on deep levels explain these results. Crystals prepared by Vertical gradient freeze method in our laboratory are compared to a commercially available detector-grade sample prepared by Travelling heater method. Comparison of crystals grown from precursors of different starting purity shows an increase of the slope of lux-ampere characteristics with a decrease of impurity content. A correlation between the slope of lux-ampere characteristics and the mobility-lifetime product of electrons was observed, too.

  2. The Influences of Bacillus subtilis on the Virulence of Aeromonas hydrophila and Expression of luxS Gene of Both Bacteria Under Co-cultivation.

    PubMed

    Ren, Yuwei; Li, Sisi; Wu, Zhixin; Zhou, Chengchong; Zhang, Ding; Chen, Xiaoxuan

    2017-06-01

    The aim of this study was to explore the influence of Bacillus subtilis CH9 on Aeromonas hydrophila SC2005. The transcription level of virulence genes of A. hydrophila SC2005 and its hemolysin activity as well as its cytotoxicity were analyzed when B. subtilis CH9 and A. hydrophila SC2005 were co-cultured. The results indicated that the transcription levels of four virulence genes of A. hydrophila, including aer, ahyB, hcp, and emp, decreased when A. hydrophila was cultured with B. subtilis CH9. Furthermore, the extracellular products of A. hydrophila showed attenuated hemolysin activity as well as cytotoxicity when A. hydrophila was cultured with B. subtilis CH9. Finally, the transcriptional levels of luxS genes of B. subtilis CH9 and A. hydrophila SC2005 were determined when these two species were co-cultured. RT-qPCR results suggested that the transcription level of A. hydrophila was down-regulated significantly. On the contrary, the transcription level of B. subtilis CH9 was up-regulated significantly. These results suggested that the probiotic role of B. subtilis CH9 is related to the inhibition of growth and virulence of A. hydrophila SC2005, and quorum sensing may be involved.

  3. Results from a search for dark matter in the complete LUX exposure

    DOE PAGES

    Akerib, D. S.; Alsum, S.; Araújo, H. M.; ...

    2017-01-11

    Here, we report constraints on spin-independent weakly interacting massive particle (WIMP)-nucleon scattering using a 3.35 ×10 4 kg day exposure of the Large Underground Xenon (LUX) experiment. A dual-phase xenon time projection chamber with 250 kg of active mass is operated at the Sanford Underground Research Facility under Lead, South Dakota (USA). With roughly fourfold improvement in sensitivity for high WIMP masses relative to our previous results, this search yields no evidence of WIMP nuclear recoils. At a WIMP mass of 50 GeV c –2, WIMP-nucleon spin-independent cross sections above 2.2 ×10 –46 cm 2 are excluded at the 90%more » confidence level. When combined with the previously reported LUX exposure, this exclusion strengthens to 1.1 × 10 –46 cm 2 at 50 GeV c –2.« less

  4. Results from a Search for Dark Matter in the Complete LUX Exposure.

    PubMed

    Akerib, D S; Alsum, S; Araújo, H M; Bai, X; Bailey, A J; Balajthy, J; Beltrame, P; Bernard, E P; Bernstein, A; Biesiadzinski, T P; Boulton, E M; Bramante, R; Brás, P; Byram, D; Cahn, S B; Carmona-Benitez, M C; Chan, C; Chiller, A A; Chiller, C; Currie, A; Cutter, J E; Davison, T J R; Dobi, A; Dobson, J E Y; Druszkiewicz, E; Edwards, B N; Faham, C H; Fiorucci, S; Gaitskell, R J; Gehman, V M; Ghag, C; Gibson, K R; Gilchriese, M G D; Hall, C R; Hanhardt, M; Haselschwardt, S J; Hertel, S A; Hogan, D P; Horn, M; Huang, D Q; Ignarra, C M; Ihm, M; Jacobsen, R G; Ji, W; Kamdin, K; Kazkaz, K; Khaitan, D; Knoche, R; Larsen, N A; Lee, C; Lenardo, B G; Lesko, K T; Lindote, A; Lopes, M I; Manalaysay, A; Mannino, R L; Marzioni, M F; McKinsey, D N; Mei, D-M; Mock, J; Moongweluwan, M; Morad, J A; Murphy, A St J; Nehrkorn, C; Nelson, H N; Neves, F; O'Sullivan, K; Oliver-Mallory, K C; Palladino, K J; Pease, E K; Phelps, P; Reichhart, L; Rhyne, C; Shaw, S; Shutt, T A; Silva, C; Solmaz, M; Solovov, V N; Sorensen, P; Stephenson, S; Sumner, T J; Szydagis, M; Taylor, D J; Taylor, W C; Tennyson, B P; Terman, P A; Tiedt, D R; To, W H; Tripathi, M; Tvrznikova, L; Uvarov, S; Verbus, J R; Webb, R C; White, J T; Whitis, T J; Witherell, M S; Wolfs, F L H; Xu, J; Yazdani, K; Young, S K; Zhang, C

    2017-01-13

    We report constraints on spin-independent weakly interacting massive particle (WIMP)-nucleon scattering using a 3.35×10^{4}  kg day exposure of the Large Underground Xenon (LUX) experiment. A dual-phase xenon time projection chamber with 250 kg of active mass is operated at the Sanford Underground Research Facility under Lead, South Dakota (USA). With roughly fourfold improvement in sensitivity for high WIMP masses relative to our previous results, this search yields no evidence of WIMP nuclear recoils. At a WIMP mass of 50  GeV c^{-2}, WIMP-nucleon spin-independent cross sections above 2.2×10^{-46}  cm^{2} are excluded at the 90% confidence level. When combined with the previously reported LUX exposure, this exclusion strengthens to 1.1×10^{-46}  cm^{2} at 50  GeV c^{-2}.

  5. Exploring the selectivity of auto-inducer complex with LuxR using molecular docking, mutational studies and molecular dynamics simulations

    NASA Astrophysics Data System (ADS)

    Rajamanikandan, Sundaraj; Srinivasan, Pappu

    2017-03-01

    Bacteria communicate with one another using extracellular signaling molecules called auto-inducers (AHLs), a process termed as quorum sensing. The quorum sensing process allows bacteria to regulate various physiological activities. In this regard, quorum sensing master regulator LuxR from Vibrio harveyi represents an attractive therapeutic target for the development of novel anti-quorum sensing agents. Eventhough the binding of AHL complex with LuxR is evidenced in earlier reports, but their mode of binding is not clearly determined. Therefore, in the present work, molecular docking, in silico mutational studies, molecular dynamics simulations and free energy calculations were performed to understand the selectivity of AHL into the binding site of LuxR. The results revealed that Asn133 and Gln137 residues play a crucial role in recognizing AHL more effectively into the binding site of LuxR with good binding free energy. In addition to that, the carbonyl group presents in the lactone ring and amide group of AHL plays a vital role in the formation of hydrogen bond interactions with the protein. Further, structure based virtual screening was performed using ChemBridge database to screen potent lead molecules against LuxR. 4-benzyl-2-pyrrolidinone and N-[2(1-cyclohexen-1-yl) enthyl]-N'(2-ethoxyphenyl) were selected based on dock score, binding affinity and mode of interactions with the receptor. Furthermore, binding free energy, density functional theory and ADME prediction were performed to rank the lead molecules. Thus, the identified lead molecules can be used for the development of anti-quorum sensing drugs.

  6. Limits on spin-dependent WIMP-nucleon cross section obtained from the complete LUX exposure

    DOE PAGES

    Akerib, D. S.; Alsum, S.; Araújo, H. M.; ...

    2017-06-23

    We present experimental constraints on the spin-dependent WIMP-nucleon elastic cross sections from the total 129.5 kg yr exposure acquired by the Large Underground Xenon experiment (LUX), operating at the Sanford Underground Research Facility in Lead, South Dakota (USA). A profile likelihood ratio analysis allows 90% C.L. upper limits to be set on the WIMP-neutron (WIMP-proton) cross section of σ n = 1.6 × 10 –41 cm 2 (σ p = 5 × 10 –40 cm 2) at 35 GeV c –2, almost a sixfold improvement over the previous LUX spin-dependent results. Finally, the spin-dependent WIMP-neutron limit is the most sensitivemore » constraint to date.« less

  7. Limits on Spin-Dependent WIMP-Nucleon Cross Section Obtained from the Complete LUX Exposure.

    PubMed

    Akerib, D S; Alsum, S; Araújo, H M; Bai, X; Bailey, A J; Balajthy, J; Beltrame, P; Bernard, E P; Bernstein, A; Biesiadzinski, T P; Boulton, E M; Brás, P; Byram, D; Cahn, S B; Carmona-Benitez, M C; Chan, C; Chiller, A A; Chiller, C; Currie, A; Cutter, J E; Davison, T J R; Dobi, A; Dobson, J E Y; Druszkiewicz, E; Edwards, B N; Faham, C H; Fallon, S R; Fiorucci, S; Gaitskell, R J; Gehman, V M; Ghag, C; Gilchriese, M G D; Hall, C R; Hanhardt, M; Haselschwardt, S J; Hertel, S A; Hogan, D P; Horn, M; Huang, D Q; Ignarra, C M; Jacobsen, R G; Ji, W; Kamdin, K; Kazkaz, K; Khaitan, D; Knoche, R; Larsen, N A; Lee, C; Lenardo, B G; Lesko, K T; Lindote, A; Lopes, M I; Manalaysay, A; Mannino, R L; Marzioni, M F; McKinsey, D N; Mei, D-M; Mock, J; Moongweluwan, M; Morad, J A; Murphy, A St J; Nehrkorn, C; Nelson, H N; Neves, F; O'Sullivan, K; Oliver-Mallory, K C; Palladino, K J; Pease, E K; Reichhart, L; Rhyne, C; Shaw, S; Shutt, T A; Silva, C; Solmaz, M; Solovov, V N; Sorensen, P; Stephenson, S; Sumner, T J; Szydagis, M; Taylor, D J; Taylor, W C; Tennyson, B P; Terman, P A; Tiedt, D R; To, W H; Tripathi, M; Tvrznikova, L; Uvarov, S; Velan, V; Verbus, J R; Webb, R C; White, J T; Whitis, T J; Witherell, M S; Wolfs, F L H; Xu, J; Yazdani, K; Young, S K; Zhang, C

    2017-06-23

    We present experimental constraints on the spin-dependent WIMP-nucleon elastic cross sections from the total 129.5  kg yr exposure acquired by the Large Underground Xenon experiment (LUX), operating at the Sanford Underground Research Facility in Lead, South Dakota (USA). A profile likelihood ratio analysis allows 90% C.L. upper limits to be set on the WIMP-neutron (WIMP-proton) cross section of σ_{n}=1.6×10^{-41}  cm^{2} (σ_{p}=5×10^{-40}  cm^{2}) at 35  GeV c^{-2}, almost a sixfold improvement over the previous LUX spin-dependent results. The spin-dependent WIMP-neutron limit is the most sensitive constraint to date.

  8. Relationship of the luminous bacterial symbiont of the Caribbean flashlight fish, Kryptophanaron alfredi (family Anomalopidae) to other luminous bacteria based on bacterial luciferase (luxA) genes.

    PubMed

    Haygood, M G

    1990-01-01

    Flashlight fishes (family Anomalopidae) have light organs that contain luminous bacterial symbionts. Although the symbionts have not yet been successfully cultured, the luciferase genes have been cloned directly from the light organ of the Caribbean species, Kryptophanaron alfredi. The goal of this project was to evaluate the relationship of the symbiont to free-living luminous bacteria by comparison of genes coding for bacterial luciferase (lux genes). Hybridization of a lux AB probe from the Kryptophanaron alfredi symbiont to DNAs from 9 strains (8 species) of luminous bacteria showed that none of the strains tested had lux genes highly similar to the symbiont. The most similar were a group consisting of Vibrio harveyi, Vibrio splendidus and Vibrio orientalis. The nucleotide sequence of the luciferase alpha subunit gene luxA) of the Kryptophanaron alfredi symbiont was determined in order to do a more detailed comparison with published luxA sequences from Vibrio harveyi, Vibrio fischeri and Photobacterium leiognathi. The hybridization results, sequence comparisons and the mol% G + C of the Kryptophanaron alfredi symbiont luxA gene suggest that the symbiont may be considered as a new species of luminous Vibrio related to Vibrio harveyi.

  9. Ultralow energy calibration of LUX detector using Xe 127 electron capture

    DOE PAGES

    Akerib, D. S.; Alsum, S.; Araújo, H. M.; ...

    2017-12-01

    We report an absolute calibration of the ionization yields(more » $$\\textit{Q$$_y$})$ and fluctuations for electronic recoil events in liquid xenon at discrete energies between 186 eV and 33.2 keV. The average electric field applied across the liquid xenon target is 180 V/cm. The data are obtained using low energy $$^{127}$$Xe electron capture decay events from the 95.0-day first run from LUX (WS2013) in search of Weakly Interacting Massive Particles (WIMPs). The sequence of gamma-ray and X-ray cascades associated with $$^{127}$$I de-excitations produces clearly identified 2-vertex events in the LUX detector. We observe the K- (binding energy, 33.2 keV), L- (5.2 keV), M- (1.1 keV), and N- (186 eV) shell cascade events and verify that the relative ratio of observed events for each shell agrees with calculations. The N-shell cascade analysis includes single extracted electron (SE) events and represents the lowest-energy electronic recoil $$\\textit{in situ}$$ measurements that have been explored in liquid xenon.« less

  10. Ultralow energy calibration of LUX detector using Xe 127 electron capture

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Akerib, D. S.; Alsum, S.; Araújo, H. M.

    We report an absolute calibration of the ionization yields (Q y) and fluctuations for electronic recoil events in liquid xenon at discrete energies between 186 eV and 33.2 keV. The average electric field applied across the liquid xenon target is 180 V/cm. The data are obtained using low energy 127Xe electron capture decay events from the 95.0-day first run from LUX (WS2013) in search of weakly interacting massive particles. The sequence of gamma-ray and x-ray cascades associated with 127I deexcitations produces clearly identified two-vertex events in the LUX detector. We observe the K-(binding energy, 33.2 keV), L-(5.2 keV), M-(1.1 keV),more » and N-(186 eV) shell cascade events and verify that the relative ratio of observed events for each shell agrees with calculations. In conclusion, the N-shell cascade analysis includes single extracted electron (SE) events and represents the lowest-energy electronic recoil in situ measurements that have been explored in liquid xenon.« less

  11. Ultralow energy calibration of LUX detector using Xe 127 electron capture

    DOE PAGES

    Akerib, D. S.; Alsum, S.; Araújo, H. M.; ...

    2017-12-28

    We report an absolute calibration of the ionization yields (Q y) and fluctuations for electronic recoil events in liquid xenon at discrete energies between 186 eV and 33.2 keV. The average electric field applied across the liquid xenon target is 180 V/cm. The data are obtained using low energy 127Xe electron capture decay events from the 95.0-day first run from LUX (WS2013) in search of weakly interacting massive particles. The sequence of gamma-ray and x-ray cascades associated with 127I deexcitations produces clearly identified two-vertex events in the LUX detector. We observe the K-(binding energy, 33.2 keV), L-(5.2 keV), M-(1.1 keV),more » and N-(186 eV) shell cascade events and verify that the relative ratio of observed events for each shell agrees with calculations. In conclusion, the N-shell cascade analysis includes single extracted electron (SE) events and represents the lowest-energy electronic recoil in situ measurements that have been explored in liquid xenon.« less

  12. Cell-Free and In Vivo Characterization of Lux, Las, and Rpa Quorum Activation Systems in E. coli.

    PubMed

    Halleran, Andrew D; Murray, Richard M

    2018-02-16

    Synthetic biologists have turned toward quorum systems as a path for building sophisticated microbial consortia that exhibit group decision making. Currently, however, even the most complex consortium circuits rely on only one or two quorum sensing systems, greatly restricting the available design space. High-throughput characterization of available quorum sensing systems is useful for finding compatible sets of systems that are suitable for a defined circuit architecture. Recently, cell-free systems have gained popularity as a test-bed for rapid prototyping of genetic circuitry. We take advantage of the transcription-translation cell-free system to characterize three commonly used Lux-type quorum activators, Lux, Las, and Rpa. We then compare the cell-free characterization to results obtained in vivo. We find significant genetic crosstalk in both the Las and Rpa systems and substantial signal crosstalk in Lux activation. We show that cell-free characterization predicts crosstalk observed in vivo.

  13. Quorum Sensing Gene Regulation by LuxR/HapR Master Regulators in Vibrios

    PubMed Central

    Ball, Alyssa S.; Chaparian, Ryan R.

    2017-01-01

    ABSTRACT The coordination of group behaviors in bacteria is accomplished via the cell-cell signaling process called quorum sensing. Vibrios have historically been models for studying bacterial communication due to the diverse and remarkable behaviors controlled by quorum sensing in these bacteria, including bioluminescence, type III and type VI secretion, biofilm formation, and motility. Here, we discuss the Vibrio LuxR/HapR family of proteins, the master global transcription factors that direct downstream gene expression in response to changes in cell density. These proteins are structurally similar to TetR transcription factors but exhibit distinct biochemical and genetic features from TetR that determine their regulatory influence on the quorum sensing gene network. We review here the gene groups regulated by LuxR/HapR and quorum sensing and explore the targets that are common and unique among Vibrio species. PMID:28484045

  14. Whole genome sequencing enables the characterization of BurI, a LuxI homologue of Burkholderia cepacia strain GG4

    PubMed Central

    Hong, Kar Wai; Chan, Kok-Gan

    2015-01-01

    Quorum sensing is a mechanism for regulating proteobacterial gene expression in response to changes in cell population. In proteobacteria, N-acyl homoserine lactone (AHL) appears to be the most widely used signalling molecules in mediating, among others, the production of extracellular virulence factors for survival. In this work, the genome of B. cepacia strain GG4, a plasmid-free strain capable of AHL synthesis was explored. In silico analysis of the 6.6 Mb complete genome revealed the presence of a LuxI homologue which correspond to Type I quorum sensing. Here, we report the molecular cloning and characterization of this LuxI homologue, designated as BurI. This 609 bp gene was cloned and overexpressed in Escherichia coli BL21(DE3). The purified protein was approximately 25 kDa and is highly similar to several autoinducer proteins of the LuxI family among Burkholderia species. To verify the AHL synthesis activity of this protein, high resolution liquid chromatography-mass spectrometry analysis revealed the production of 3-oxo-hexanoylhomoserine lactone, N-octanoylhomoserine lactone and 3-hydroxy-octanoylhomoserine lactone from induced E. coli BL21 harboring the recombinant BurI. Our data show, for the first time, the cloning and characterization of the LuxI homologue from B. cepacia strain GG4 and confirmation of its AHL synthesis activity. PMID:26290785

  15. Technical results from the surface run of the LUX dark matter experiment

    DOE PAGES

    Akerib, D. S.; Bai, X.; Bernard, E.; ...

    2013-03-07

    We present the results of the three-month above-ground commissioning run of the Large Underground Xenon (LUX) experiment at the Sanford Underground Research Facility located in Lead, South Dakota, USA. LUX is a 370 kg liquid xenon detector that will search for cold dark matter in the form of Weakly Interacting Massive Particles (WIMPs). The commissioning run, conducted with the detector immersed in a water tank, validated the integration of the various sub-systems in preparation of the underground deployment. Using the data collected, we report excellent light collection properties, achieving 8.4 photoelectrons per keV for 662 keV electron recoils without anmore » applied electric field, measured in the center of the WIMP target. Here, we also find good energy and position resolution in relatively high-energy interactions from a variety of internal and external sources. Finally, we have used the commissioning data to tune the optical properties of our simulation and report updated sensitivity projections for spin-independent WIMP-nucleon scattering.« less

  16. Roles of a solo LuxR in the biological control agent Lysobacter enzymogenes strain OH11.

    PubMed

    Qian, Guoliang; Xu, Feifei; Venturi, Vittorio; Du, Liangcheng; Liu, Fengquan

    2014-03-01

    Lysobacter enzymogenes is a ubiquitous plant-associated and environmentally friendly bacterium emerging as a novel biological control agent of plant disease. This bacterium produces diverse antifungal factors, such as lytic enzymes and a secondary metabolite (heat-stable antifungal factor [HSAF]) having antifungal activity with a novel structure and mode of action. The regulatory mechanisms for biosynthesis of antifungal factors is largely unknown in L. enzymogenes. The solo LuxR proteins have been shown to be widespread, playing important roles in plant-associated bacteria. Here, we cloned and studied a solo LuxR protein, LesR, from L. enzymogenes strain OH11. Overexpression but not deletion of lesR significantly impaired HSAF biosynthesis levels and antimicrobial activities but did not show visible effect on production of major lytic enzymes. Overexpression of lesR also led to remarkably accelerated cell aggregation and induced production of a melanin-like pigment in L. enzymogenes; these two phenotypes are mediated by the diffusible factor cell-to-cell signaling system of L. enzymogenes. The C-terminus helix-turn-helix domain was shown to be critical for several lesR-controlled functions. Overall, our study provides the first example of the roles and mechanisms of a solo LuxR protein in a plant-associated L. enzymogenes.

  17. LUX-ZEPLIN (LZ) Conceptual Design Report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Akerib, D. S.

    2015-03-09

    The design and performance of the LUX-ZEPLIN (LZ) detector is described as of March 2015 in this Conceptual Design Report. LZ is a second-generation dark-matter detector with the potential for unprecedented sensitivity to weakly interacting massive particles (WIMPs) of masses from a few GeV/c 2 to hundreds of TeV/c 2. With total liquid xenon mass of about 10 tonnes, LZ will be the most sensitive experiment for WIMPs in this mass region by the end of the decade. This report describes in detail the design of the LZ technical systems. Expected backgrounds are quantified and the performance of the experimentmore » is presented. The LZ detector will be located at the Sanford Underground Research Facility in South Dakota. The organization of the LZ Project and a summary of the expected cost and current schedule are given.« less

  18. Construction and symbiotic competence of a luxA-deletion mutant of Vibrio fischeri.

    PubMed

    Visick, K G; Ruby, E G

    1996-10-10

    Bioluminescence by the squid Euprymna scolopes requires colonization of its light organ by the symbiotic luminous bacterium Vibrio fischeri. Investigation of the genetic determinants underlying bacterial symbiotic competence in this system has necessitated the continuing establishment and application of molecular genetic techniques in V. fischeri. We developed a procedure for the introduction of plasmid DNA into V. fischeri by electroporation, and isolated a mutant strain that overcame the apparent restriction barrier between V. fischeri and Escherichia coli. Using the technique of electroporation in combination with that of gene replacement, we constructed a non-luminous strain of V. fischeri (delta luxA::erm). In addition, we used the transducing phage rp-1 for the first time to transfer a chromosomal antibiotic resistance marker to another strain of V. fischeri. The luxA mutant was able to colonize E. scolopes as quickly and to the same extent as wild type. This result suggested that, at least during the initial stages of colonization, luminescence per se is not an essential factor for the symbiotic infection.

  19. HvLUX1 is a candidate gene underlying the early maturity 10 locus in barley: phylogeny, diversity, and interactions with the circadian clock and photoperiodic pathways

    PubMed Central

    Campoli, Chiara; Pankin, Artem; Drosse, Benedikt; Casao, Cristina M; Davis, Seth J; von Korff, Maria

    2013-01-01

    Photoperiodic flowering is a major factor determining crop performance and is controlled by interactions between environmental signals and the circadian clock. We proposed Hvlux1, an ortholog of the Arabidopsis circadian gene LUX ARRHYTHMO, as a candidate underlying the early maturity 10 (eam10) locus in barley (Hordeum vulgare L.). The link between eam10 and Hvlux1 was discovered using high-throughput sequencing of enriched libraries and segregation analysis. We conducted functional, phylogenetic, and diversity studies of eam10 and HvLUX1 to understand the genetic control of photoperiod response in barley and to characterize the evolution of LUX-like genes within barley and across monocots and eudicots. We demonstrate that eam10 causes circadian defects and interacts with the photoperiod response gene Ppd-H1 to accelerate flowering under long and short days. The results of phylogenetic and diversity analyses indicate that HvLUX1 was under purifying selection, duplicated at the base of the grass clade, and diverged independently of LUX-like genes in other plant lineages. Taken together, these findings contribute to improved understanding of the barley circadian clock, its interaction with the photoperiod pathway, and evolution of circadian systems in barley and across monocots and eudicots. PMID:23731278

  20. The LUX prototype detector: Heat exchanger development

    DOE PAGES

    Akerib, D. S.; Bai, X.; Bedikian, S.; ...

    2013-01-24

    The LUX (large underground xenon) detector is a two-phase xenon time projection chamber (TPC) designed to search for WIMP–nucleon dark matter interactions. As with all noble element detectors, continuous purification of the detector medium is essential to produce a large (> 1 ms) electron lifetime; this is necessary for efficient measurement of the electron signal which in turn is essential for achieving robust discrimination of signal from background events. Here, we describe the development of a novel purification system deployed in a prototype detector. The results from the operation of this prototype indicated heat exchange with an efficiency above 94%more » up to a flow rate of 42 slpm, allowing for an electron drift length greater than 1 m to be achieved in approximately 2 days and sustained for the duration of the testing period.« less

  1. Position reconstruction in LUX

    DOE PAGES

    Akerib, D. S.; Alsum, S.; Araújo, H. M.; ...

    2018-02-01

    The (x, y) position reconstruction method used in the analysis of the complete exposure of the Large Underground Xenon (LUX) experiment is presented. The algorithm is based on a statistical test that makes use of an iterative method to recover the photomultiplier tube (PMT) light response directly from the calibration data. The light response functions make use of a two dimensional functional form to account for the photons reflected on the inner walls of the detector. To increase the resolution for small pulses, a photon counting technique was employed to describe the response of the PMTs. The reconstruction was assessedmore » with calibration data including 83mKr (releasing a total energy of 41.5 keV) and 3H (β - with Q = 18.6 keV) decays, and a deuterium-deuterium (D-D) neutron beam (2.45 MeV). Within the detector's fiducial volume, the reconstruction has achieved an (x, y) position uncertainty of σ = 0.82 cm and σ = 0.17 cm for events of only 200 and 4,000 detected electroluminescence photons respectively. Such signals are associated with electron recoils of energies ~0.25 keV and ~10 keV, respectively. Lastly, the reconstructed position of the smallest events with a single electron emitted from the liquid surface (22 detected photons) has a horizontal (x, y) uncertainty of 2.13 cm.« less

  2. Position reconstruction in LUX

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Akerib, D. S.; Alsum, S.; Araújo, H. M.

    The (x, y) position reconstruction method used in the analysis of the complete exposure of the Large Underground Xenon (LUX) experiment is presented. The algorithm is based on a statistical test that makes use of an iterative method to recover the photomultiplier tube (PMT) light response directly from the calibration data. The light response functions make use of a two dimensional functional form to account for the photons reflected on the inner walls of the detector. To increase the resolution for small pulses, a photon counting technique was employed to describe the response of the PMTs. The reconstruction was assessedmore » with calibration data including 83mKr (releasing a total energy of 41.5 keV) and 3H (β - with Q = 18.6 keV) decays, and a deuterium-deuterium (D-D) neutron beam (2.45 MeV). Within the detector's fiducial volume, the reconstruction has achieved an (x, y) position uncertainty of σ = 0.82 cm and σ = 0.17 cm for events of only 200 and 4,000 detected electroluminescence photons respectively. Such signals are associated with electron recoils of energies ~0.25 keV and ~10 keV, respectively. Lastly, the reconstructed position of the smallest events with a single electron emitted from the liquid surface (22 detected photons) has a horizontal (x, y) uncertainty of 2.13 cm.« less

  3. Position reconstruction in LUX

    NASA Astrophysics Data System (ADS)

    Akerib, D. S.; Alsum, S.; Araújo, H. M.; Bai, X.; Bailey, A. J.; Balajthy, J.; Beltrame, P.; Bernard, E. P.; Bernstein, A.; Biesiadzinski, T. P.; Boulton, E. M.; Brás, P.; Byram, D.; Cahn, S. B.; Carmona-Benitez, M. C.; Chan, C.; Currie, A.; Cutter, J. E.; Davison, T. J. R.; Dobi, A.; Druszkiewicz, E.; Edwards, B. N.; Fallon, S. R.; Fan, A.; Fiorucci, S.; Gaitskell, R. J.; Genovesi, J.; Ghag, C.; Gilchriese, M. G. D.; Hall, C. R.; Hanhardt, M.; Haselschwardt, S. J.; Hertel, S. A.; Hogan, D. P.; Horn, M.; Huang, D. Q.; Ignarra, C. M.; Jacobsen, R. G.; Ji, W.; Kamdin, K.; Kazkaz, K.; Khaitan, D.; Knoche, R.; Larsen, N. A.; Lenardo, B. G.; Lesko, K. T.; Lindote, A.; Lopes, M. I.; Manalaysay, A.; Mannino, R. L.; Marzioni, M. F.; McKinsey, D. N.; Mei, D.-M.; Mock, J.; Moongweluwan, M.; Morad, J. A.; Murphy, A. St. J.; Nehrkorn, C.; Nelson, H. N.; Neves, F.; O'Sullivan, K.; Oliver-Mallory, K. C.; Palladino, K. J.; Pease, E. K.; Rhyne, C.; Shaw, S.; Shutt, T. A.; Silva, C.; Solmaz, M.; Solovov, V. N.; Sorensen, P.; Sumner, T. J.; Szydagis, M.; Taylor, D. J.; Taylor, W. C.; Tennyson, B. P.; Terman, P. A.; Tiedt, D. R.; To, W. H.; Tripathi, M.; Tvrznikova, L.; Uvarov, S.; Velan, V.; Verbus, J. R.; Webb, R. C.; White, J. T.; Whitis, T. J.; Witherell, M. S.; Wolfs, F. L. H.; Xu, J.; Yazdani, K.; Young, S. K.; Zhang, C.

    2018-02-01

    The (x, y) position reconstruction method used in the analysis of the complete exposure of the Large Underground Xenon (LUX) experiment is presented. The algorithm is based on a statistical test that makes use of an iterative method to recover the photomultiplier tube (PMT) light response directly from the calibration data. The light response functions make use of a two dimensional functional form to account for the photons reflected on the inner walls of the detector. To increase the resolution for small pulses, a photon counting technique was employed to describe the response of the PMTs. The reconstruction was assessed with calibration data including 83mKr (releasing a total energy of 41.5 keV) and 3H (β- with Q = 18.6 keV) decays, and a deuterium-deuterium (D-D) neutron beam (2.45 MeV) . Within the detector's fiducial volume, the reconstruction has achieved an (x, y) position uncertainty of σ = 0.82 cm and σ = 0.17 cm for events of only 200 and 4,000 detected electroluminescence photons respectively. Such signals are associated with electron recoils of energies ~0.25 keV and ~10 keV, respectively. The reconstructed position of the smallest events with a single electron emitted from the liquid surface (22 detected photons) has a horizontal (x, y) uncertainty of 2.13 cm.

  4. Bactericidal effect of bovine lactoferrin and synthetic peptide lactoferrin chimera in Streptococcus pneumoniae and the decrease in luxS gene expression by lactoferrin.

    PubMed

    León-Sicairos, Nidia; Angulo-Zamudio, Uriel A; Vidal, Jorge E; López-Torres, Cynthia A; Bolscher, Jan G M; Nazmi, Kamran; Reyes-Cortes, Ruth; Reyes-López, Magda; de la Garza, Mireya; Canizalez-Román, Adrian

    2014-10-01

    Streptococcus pneumoniae (pneumococcus) is responsible for nearly one million child deaths annually. Pneumococcus causes infections such as pneumonia, otitis media, meningitis, and sepsis. The human immune system includes antibacterial peptides and proteins such as lactoferrin (LF), but its activity against pneumococcus is not fully understood. The aim of this work was to evaluate the bactericidal effect of bovine lactoferrin (bLF) and the synthetic LF-peptides lactoferricin (LFcin17-30), lactoferrampin (LFampin265-284), and LFchimera against S. pneumoniae planktonic cells. The mechanism of damage was also investigated, as well as the impact of these peptides on the transcription levels of genes known to encode important virulence factors. S. pneumoniae planktonic cells were treated with bLF, LFcin17-30, LFampin265-284 and LFchimera at different time points. The viability of treated planktonic cells was assessed by dilution and plating (in CFU/ml). The interaction between LF and LF-peptides coupled to fluorescein was visualized using a confocal microscope and flow cytometry, whereas the damage at structural levels was observed by electron microscopy. Damage to bacterial membranes was further evaluated by membrane permeabilization by use of propidium iodide and flow cytometry, and finally, the expression of pneumococcal genes was evaluated by qRT-PCR. bLF and LFchimera were the best bactericidal agents. bLF and peptides interacted with bacteria causing changes in the shape and size of the cell and membrane permeabilization. Moreover, the luxS gene was down-regulated in bacteria treated with LF. In conclusion, LF and LFchimera have a bactericidal effect, and LF down-regulates genes involved in the pathogenicity of pneumococcus, thus demonstrating potential as new agents for the treatment of pneumococcal infections.

  5. First Results of the LUX Dark Matter Experiment

    NASA Astrophysics Data System (ADS)

    Carmona-Benitez, M. C.; Akerib, D. S.; Araújo, H. M.; Bai, X.; Bailey, A. J.; Balajthy, J.; Beltrame, P.; Bernard, E.; Bernstein, A.; Bradley, A.; Byram, D.; Cahn, S. B.; Chan, C.; Chapman, J. J.; Chiller, A. A.; Chiller, C.; Currie, A.; de Viveiros, L.; Dobi, A.; Dobson, J.; Druszkiewicz, E.; Edwards, B.; Faham, C. H.; Fiorucci, S.; Flores, C.; Gaitskell, R. J.; Gehman, V. M.; Ghag, C.; Gibson, K. R.; Gilchriese, M. G. D.; Hall, C.; Hanhardt, M.; Haselschwardt, S.; Hertel, S. A.; Horn, M.; Huang, D. Q.; Ihm, M.; Jacobsen, R. G.; Kazkaz, K.; Knoche, R.; Larsen, N. A.; Lee, C.; Lenardo, B.; Lesko, K. T.; Lindote, A.; Lopes, M. I.; Malling, D. C.; Manalaysay, A.; Mannino, R.; McKinsey, D. N.; Mei, D.-M.; Mock, J.; Moongweluwan, M.; Morad, J.; Murphy, A. St. J.; Nehrkorn, C.; Nelson, H.; Neves, F.; Ott, R. A.; Pangilinan, M.; Parker, P. D.; Pease, E. K.; Pech, K.; Phelps, P.; Reichhart, L.; Shutt, T.; Silva, C.; Solovov, V. N.; Sorensen, P.; O'Sullivan, K.; Sumner, T. J.; Szydagis, M.; Taylor, D.; Tennyson, B.; Tiedt, D. R.; Tripathi, M.; Tvrznikova, L.; Uvarov, S.; Verbus, J. R.; Walsh, N.; Webb, R.; White, J. T.; Witherell, M. S.; Wolfs, F. L. H.; Woods, M.; Zhang, C.; LUX Collaboration

    2016-04-01

    LUX (Large Underground Xenon) is a dark matter direct detection experiment deployed at the 4850' level of the Sanford Underground Research Facility (SURF) in Lead, SD, operating a 370 kg dual-phase xenon TPC. Results of the first WIMP search run were presented in late 2013, for the analysis of 85.3 live-days with a fiducial volume of 118 kg, taken during the period of April to August 2013. The experiment exhibited a sensitivity to spin-independent WIMP-nucleon elastic scattering with a minimum upper limit on the cross section of 7.6 ×10-46cm2 at a WIMP mass of 33 GeV/c2, becoming the world's leading WIMP search result, in conflict with several previous claimed hints of discovery.

  6. Sensitive detection of viable Escherichia coli O157:H7 from foods using a luciferase-reporter phage phiV10lux.

    PubMed

    Kim, Jinwoo; Kim, Minsik; Kim, Seongmi; Ryu, Sangryeol

    2017-08-02

    Escherichia coli O157:H7, a major foodborne pathogen, is a major public health concern associated with life-threatening diseases such as hemolytic uremic syndrome. To alleviate this burden, a sensitive and rapid system is required to detect this pathogen in various kinds of foods. Herein, we propose a phage-based pathogen detection method to replace laborious and time-consuming conventional methods. We engineered an E. coli O157:H7-specific phage phiV10 to rapidly and sensitively detect this notorious pathogen. The luxCDABE operon was introduced into the phiV10 genome and allowed the engineered phage phiV10lux to generate bioluminescence proportional to the number of viable E. coli O157:H7 cells without any substrate addition. The phage phiV10lux was able to detect at least 1CFU/ml of E. coli O157:H7 in a pure culture within 40min after 5h of pre-incubation. In artificially contaminated romaine lettuce, apple juice (pH3.51), and ground beef, the reporter phage could detect approximately 10CFU/cm 2 , 13CFU/ml, and 17CFU/g of E. coli O157:H7, respectively. Taken together, the constructed reporter phage phiV10lux could be applied as a powerful tool for rapid and sensitive detection of live E. coli O157:H7 in foods. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. PhylloLux technology for crop protection: alternative management of diseases and arthropods for strawberry production

    USDA-ARS?s Scientific Manuscript database

    A search for alternatives to synthetic fungicides for control of strawberry diseases has led us to the development of PhylloLux© technology that combines UV-C irradiation followed by a specific dark period (2-4 hr depending on pathogen) and application of microbial antagonists. This technology is s...

  8. First Results of the LUX Dark Matter Experiment

    DOE PAGES

    Carmona-Benitez, M. C.; Akerib, D. S.; Araújo, H. M.; ...

    2016-05-31

    LUX (Large Underground Xenon) is a dark matter direct detection experiment deployed at the 4850' level of the Sanford Underground Research Facility (SURF) in Lead, SD, operating a 370 kg dual-phase xenon TPC. Results of the first WIMP search run were presented in late 2013, for the analysis of 85.3 live-days with a fiducial volume of 118 kg, taken during the period of April to August 2013. The experiment exhibited a sensitivity to spin-independent WIMP-nucleon elastic scattering with a minimum upper limit on the cross section of 7.6×10 -46 cm 2 at a WIMP mass of 33 GeV/c 2, thusmore » becoming the world's leading WIMP search result, in conflict with several previous claimed hints of discovery.« less

  9. First Results of the LUX Dark Matter Experiment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Carmona-Benitez, M. C.; Akerib, D. S.; Araújo, H. M.

    LUX (Large Underground Xenon) is a dark matter direct detection experiment deployed at the 4850' level of the Sanford Underground Research Facility (SURF) in Lead, SD, operating a 370 kg dual-phase xenon TPC. Results of the first WIMP search run were presented in late 2013, for the analysis of 85.3 live-days with a fiducial volume of 118 kg, taken during the period of April to August 2013. The experiment exhibited a sensitivity to spin-independent WIMP-nucleon elastic scattering with a minimum upper limit on the cross section of 7.6×10 -46 cm 2 at a WIMP mass of 33 GeV/c 2, thusmore » becoming the world's leading WIMP search result, in conflict with several previous claimed hints of discovery.« less

  10. Position reconstruction in LUX

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Akerib, D. S.; Alsum, S.; Araújo, H. M.

    © 2018 IOP Publishing Ltd and Sissa Medialab. The (x, y) position reconstruction method used in the analysis of the complete exposure of the Large Underground Xenon (LUX) experiment is presented. The algorithm is based on a statistical test that makes use of an iterative method to recover the photomultiplier tube (PMT) light response directly from the calibration data. The light response functions make use of a two dimensional functional form to account for the photons reflected on the inner walls of the detector. To increase the resolution for small pulses, a photon counting technique was employed to describe themore » response of the PMTs. The reconstruction was assessed with calibration data including 83m Kr (releasing a total energy of 41.5 keV) and 3 H (andbeta; - with Q = 18.6 keV) decays, and a deuterium-deuterium (D-D) neutron beam (2.45 MeV) . Within the detector's fiducial volume, the reconstruction has achieved an (x, y) position uncertainty of andsigma; = 0.82 cm and andsigma; = 0.17 cm for events of only 200 and 4,000 detected electroluminescence photons respectively. Such signals are associated with electron recoils of energies andsim;0.25 keV and andsim;10 keV, respectively. The reconstructed position of the smallest events with a single electron emitted from the liquid surface (22 detected photons) has a horizontal (x, y) uncertainty of 2.13 cm.« less

  11. Position reconstruction in LUX

    DOE PAGES

    Akerib, D. S.; Alsum, S.; Araújo, H. M.; ...

    2018-02-01

    © 2018 IOP Publishing Ltd and Sissa Medialab. The (x, y) position reconstruction method used in the analysis of the complete exposure of the Large Underground Xenon (LUX) experiment is presented. The algorithm is based on a statistical test that makes use of an iterative method to recover the photomultiplier tube (PMT) light response directly from the calibration data. The light response functions make use of a two dimensional functional form to account for the photons reflected on the inner walls of the detector. To increase the resolution for small pulses, a photon counting technique was employed to describe themore » response of the PMTs. The reconstruction was assessed with calibration data including 83m Kr (releasing a total energy of 41.5 keV) and 3 H (andbeta; - with Q = 18.6 keV) decays, and a deuterium-deuterium (D-D) neutron beam (2.45 MeV) . Within the detector's fiducial volume, the reconstruction has achieved an (x, y) position uncertainty of andsigma; = 0.82 cm and andsigma; = 0.17 cm for events of only 200 and 4,000 detected electroluminescence photons respectively. Such signals are associated with electron recoils of energies andsim;0.25 keV and andsim;10 keV, respectively. The reconstructed position of the smallest events with a single electron emitted from the liquid surface (22 detected photons) has a horizontal (x, y) uncertainty of 2.13 cm.« less

  12. High-throughput quantitative luminescence assay of the growth in planta of Pseudomonas syringae chromosomally tagged with Photorhabdus luminescens luxCDABE.

    PubMed

    Fan, Jun; Crooks, Casey; Lamb, Chris

    2008-01-01

    Bioluminescent strains of the Arabidopsis thaliana pathogens Pseudomonas syringae pathovar (pv.) tomato and pv. maculicola were made by insertion of the luxCDABE operon from Photorhabdus luminescens into the P. syringae chromosome under the control of a constitutive promoter. Stable integration of luxCDABE did not affect bacterial fitness, growth in planta or disease outcome. Luminescence accurately and reliably reported bacterial growth in infected Arabidopsis leaves both with a fixed inoculum followed over time and with varying inocula assayed at a single time point. Furthermore, the bioluminescence assay could detect a small (1.3-fold) difference in bacterial growth between different plant genotypes with a precision comparable to that of the standard plate assay. Luminescence of luxCDABE-tagged P. syringae allows rapid and convenient quantification of bacterial growth without the tissue extraction, serial dilution, plating and manual scoring involved in standard assays of bacterial growth by colony formation in plate culture of samples from infected tissue. The utility of the bioluminescence assay was illustrated by surveying the 500-fold variation in growth of the universally virulent P. syringae pv. maculicola ES4326 among more than 100 Arabidopsis ecotypes and identification of two quantitative trait loci accounting for 48% and 16%, respectively, of the variance of basal resistance to P. syringae pv. tomato DC3000 in the Col-0 x Fl-1 F(2) population. Luminescence assay of bacteria chromosomally tagged with luxCDABE should greatly facilitate the genetic dissection of quantitative differences in gene-for-gene, basal and acquired disease resistance and other aspects of plant interactions with bacterial pathogens requiring high-throughput assays or large-scale quantitative screens.

  13. Ultralow energy calibration of LUX detector using Xe 127 electron capture

    NASA Astrophysics Data System (ADS)

    Akerib, D. S.; Alsum, S.; Araújo, H. M.; Bai, X.; Bailey, A. J.; Balajthy, J.; Beltrame, P.; Bernard, E. P.; Bernstein, A.; Biesiadzinski, T. P.; Boulton, E. M.; Brás, P.; Byram, D.; Cahn, S. B.; Carmona-Benitez, M. C.; Chan, C.; Currie, A.; Cutter, J. E.; Davison, T. J. R.; Dobi, A.; Druszkiewicz, E.; Edwards, B. N.; Fallon, S. R.; Fan, A.; Fiorucci, S.; Gaitskell, R. J.; Genovesi, J.; Ghag, C.; Gilchriese, M. G. D.; Hall, C. R.; Hanhardt, M.; Haselschwardt, S. J.; Hertel, S. A.; Hogan, D. P.; Horn, M.; Huang, D. Q.; Ignarra, C. M.; Jacobsen, R. G.; Ji, W.; Kamdin, K.; Kazkaz, K.; Khaitan, D.; Knoche, R.; Larsen, N. A.; Lenardo, B. G.; Lesko, K. T.; Lindote, A.; Lopes, M. I.; Manalaysay, A.; Mannino, R. L.; Marzioni, M. F.; McKinsey, D. N.; Mei, D.-M.; Mock, J.; Moongweluwan, M.; Morad, J. A.; Murphy, A. St. J.; Nehrkorn, C.; Nelson, H. N.; Neves, F.; O'Sullivan, K.; Oliver-Mallory, K. C.; Palladino, K. J.; Pease, E. K.; Rhyne, C.; Shaw, S.; Shutt, T. A.; Silva, C.; Solmaz, M.; Solovov, V. N.; Sorensen, P.; Sumner, T. J.; Szydagis, M.; Taylor, D. J.; Taylor, W. C.; Tennyson, B. P.; Terman, P. A.; Tiedt, D. R.; To, W. H.; Tripathi, M.; Tvrznikova, L.; Uvarov, S.; Velan, V.; Verbus, J. R.; Webb, R. C.; White, J. T.; Whitis, T. J.; Witherell, M. S.; Wolfs, F. L. H.; Xu, J.; Yazdani, K.; Young, S. K.; Zhang, C.

    2017-12-01

    We report an absolute calibration of the ionization yields (Qy ) and fluctuations for electronic recoil events in liquid xenon at discrete energies between 186 eV and 33.2 keV. The average electric field applied across the liquid xenon target is 180 V /cm . The data are obtained using low energy Xe 127 electron capture decay events from the 95.0-day first run from LUX (WS2013) in search of weakly interacting massive particles. The sequence of gamma-ray and x-ray cascades associated with I 127 deexcitations produces clearly identified two-vertex events in the LUX detector. We observe the K-(binding energy, 33.2 keV), L-(5.2 keV), M-(1.1 keV), and N-(186 eV) shell cascade events and verify that the relative ratio of observed events for each shell agrees with calculations. The N-shell cascade analysis includes single extracted electron (SE) events and represents the lowest-energy electronic recoil in situ measurements that have been explored in liquid xenon.

  14. Development of stable reporter system cloning luxCDABE genes into chromosome of Salmonella enterica serotypes using Tn7 transposon.

    PubMed

    Howe, Kevin; Karsi, Attila; Germon, Pierre; Wills, Robert W; Lawrence, Mark L; Bailey, Richard H

    2010-07-23

    Salmonellosis may be a food safety problem when raw food products are mishandled and not fully cooked. In previous work, we developed bioluminescent Salmonella enterica serotypes using a plasmid-based reporting system that can be used for real-time monitoring of the pathogen's growth on food products in short term studies. In this study, we report the use of a Tn7-based transposon system for subcloning of luxCDABE genes into the chromosome of eleven Salmonella enterica serotypes isolated from the broiler production continuum. We found that the lux operon is constitutively expressed from the chromosome post-transposition and the lux cassette is stable without external pressure, i.e. antibiotic selection, for all Salmonella enterica serotypes used. Bioluminescence expression is based on an active electron transport chain and is directly related with metabolic activity. This relationship was quantified by measuring bioluminescence against a temperature gradient in aqueous solution using a luminometer. In addition, bioluminescent monitoring of two serotypes confirmed that our chicken skin model has the potential to be used to evaluate pathogen mitigation strategies. This study demonstrated that our new stable reporting system eliminates bioluminescence variation due to plasmid instability and provides a reliable real-time experimental system to study application of preventive measures for Salmonella on food products in real-time for both short and long term studies.

  15. Identification of the Regulon of AphB and Its Essential Roles in LuxR and Exotoxin Asp Expression in the Pathogen Vibrio alginolyticus.

    PubMed

    Gao, Xiating; Liu, Yang; Liu, Huan; Yang, Zhen; Liu, Qin; Zhang, Yuanxing; Wang, Qiyao

    2017-10-15

    In Vibrio species, AphB is essential to activate virulence cascades by sensing low-pH and anaerobiosis signals; however, its regulon remains largely unknown. Here, AphB is found to be a key virulence regulator in Vibrio alginolyticus , a pathogen for marine animals and humans. Chromatin immunoprecipitation followed by high-throughput DNA sequencing (ChIP-seq) enabled the detection of 20 loci in the V. alginolyticus genome that contained AphB-binding peaks. An AphB-specific binding consensus was confirmed by electrophoretic mobility shift assays (EMSAs), and the regulation of genes flanking such binding sites was demonstrated using quantitative real-time PCR analysis. AphB binds directly to its own promoter and positively controls its own expression in later growth stages. AphB also activates the expression of the exotoxin Asp by binding directly to the promoter regions of asp and the master quorum-sensing (QS) regulator luxR DNase I footprinting analysis uncovered distinct AphB-binding sites (BBS) in these promoters. Furthermore, a BBS in the luxR promoter region overlaps that of LuxR-binding site I, which mediates the positive control of luxR promoter activity by AphB. This study provides new insights into the AphB regulon and reveals the mechanisms underlying AphB regulation of physiological adaptation and QS-controlled virulence in V. alginolyticus IMPORTANCE In this work, AphB is determined to play essential roles in the expression of genes associated with QS, physiology, and virulence in V. alginolyticus , a pathogen for marine animals and humans. AphB was found to bind directly to 20 genes and control their expression by a 17-bp consensus binding sequence. Among the 20 genes, the aphB gene itself was identified to be positively autoregulated, and AphB also positively controlled asp and luxR expression. Taken together, these findings improve our understanding of the roles of AphB in controlling physiological adaptation and QS-controlled virulence gene

  16. The AstraLux Multiplicity Survey: Extension to Late M-dwarfs

    NASA Astrophysics Data System (ADS)

    Janson, Markus; Bergfors, Carolina; Brandner, Wolfgang; Kudryavtseva, Natalia; Hormuth, Felix; Hippler, Stefan; Henning, Thomas

    2014-07-01

    The distribution of multiplicity among low-mass stars is a key issue to understanding the formation of stars and brown dwarfs, and recent surveys have yielded large enough samples of nearby low-mass stars to study this issue statistically to good accuracy. Previously, we have presented a multiplicity study of ~700 early/mid M-type stars observed with the AstraLux high-resolution Lucky Imaging cameras. Here, we extend the study of multiplicity in M-type stars through studying 286 nearby mid/late M-type stars, bridging the gap between our previous study and multiplicity studies of brown dwarfs. Most of the targets have been observed more than once, allowing us to assess common proper motion to confirm companionship. We detect 68 confirmed or probable companions in 66 systems, of which 41 were previously undiscovered. Detections are made down to the resolution limit of ~100 mas of the instrument. The raw multiplicity in the AstraLux sensitivity range is 17.9%, leading to a total multiplicity fraction of 21%-27% depending on the mass ratio distribution, which is consistent with being flat down to mass ratios of ~0.4, but cannot be stringently constrained below this value. The semi-major axis distribution is well represented by a log-normal function with μa = 0.78 and σa = 0.47, which is narrower and peaked at smaller separations than for a Sun-like sample. This is consistent with a steady decrease in average semi-major axis from the highest-mass binary stars to the brown dwarf binaries. Based on observations collected at the Centro Astronómico Hispano Alemán (CAHA) at Calar Alto, operated jointly by the Max-Planck Institute for Astronomy and the Instituto de Astrofísica de Andalucía (CSIC).

  17. 2.7 MeV Ar11+ ion irradiation induced structural evolution in Lu2(Ti2-xLux)O7-x/2 pyrochlores

    NASA Astrophysics Data System (ADS)

    Yang, D. Y.; Liu, C. G.; Zhang, K. Q.; Xia, Y.; Chen, L. J.; Liu, H.; Li, Y. H.

    2015-11-01

    This paper aims to study the radiation effects of nonstoichiometric pyrochlore series Lu2(Ti2-xLux)O7-x/2 (x = 0-0.667). Polycrystalline Lu2(Ti2-xLux)O7-x/2 samples were irradiated with 2.7 MeV Ar11+ ions up to a fluence of 8 × 1014 ions/cm2. The irradiated samples were characterized using grazing incidence X-ray diffraction technique. The results reveal that Lu2(Ti2-xLux)O7-x/2 samples undergo significant amorphization and lattice swelling upon irradiation. Specifically, the amorphization process is predominantly driven by ballistic nuclear energy deposition of Ar11+ ions at this energy regime, which can be well described by a direct-impact/defect-stimulated model. Both the amorphization fraction and the relative variation of lattice parameter decrease with increasing x, showing a strong dependence on the chemical composition. The results are then discussed in the framework of the structural disorder and recovery ability from damage, applying an atomic layer model.

  18. Multipartite interacting scalar dark matter in the light of updated LUX data

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bhattacharya, Subhaditya; Ghosh, Purusottam; Poulose, Poulose, E-mail: subhab@iitg.ernet.in, E-mail: p.ghosh@iitg.ernet.in, E-mail: poulose@iitg.ernet.in

    2017-04-01

    We explore constraints on multipartite dark matter (DM) framework composed of singlet scalar DM interacting with the Standard Model (SM) through Higgs portal coupling. We compute relic density and direct search constraints including the updated LUX bound for two component scenario with non-zero interactions between two DM components in Z{sub 2} × Z{sub 2}{sup '} framework in comparison with the one having O(2) symmetry. We point out availability of a significantly large region of parameter space of such a multipartite model with DM-DM interactions.

  19. Circulation and Purification in the LUX-ZEPLIN System Test

    NASA Astrophysics Data System (ADS)

    Alsum, Shaun; Lz Collaboration

    2016-03-01

    LZ is a dark-matter direct detection experiment whose detector is a two-phase TPC using approximately seven tons of active xenon as its scintillator. The xenon must have few electronegative impurities to ensure sufficient electron transport through the drift region. The LZ purification system is being prototyped in the LZ system test, a test platform located at SLAC using about 100kg of Xenon, which consists of gas circulation through a SAES getter. We utilize a dual-phase and a gas-phase heat exchanger to reduce needed cooling power. To achieve this circulation we employ an all metal seal triple diaphragm pump, also prototyped in the System Test. This talk will present early results from the system test as well as some baseline LZ designs. The LUX-ZEPLIN dark matter direct detection experiment.

  20. Liquid xenon scintillation measurements and pulse shape discrimination in the LUX dark matter detector

    NASA Astrophysics Data System (ADS)

    Akerib, D. S.; Alsum, S.; Araújo, H. M.; Bai, X.; Bailey, A. J.; Balajthy, J.; Beltrame, P.; Bernard, E. P.; Bernstein, A.; Biesiadzinski, T. P.; Boulton, E. M.; Brás, P.; Byram, D.; Carmona-Benitez, M. C.; Chan, C.; Currie, A.; Cutter, J. E.; Davison, T. J. R.; Dobi, A.; Druszkiewicz, E.; Edwards, B. N.; Fallon, S. R.; Fan, A.; Fiorucci, S.; Gaitskell, R. J.; Genovesi, J.; Ghag, C.; Gilchriese, M. G. D.; Hall, C. R.; Haselschwardt, S. J.; Hertel, S. A.; Hogan, D. P.; Horn, M.; Huang, D. Q.; Ignarra, C. M.; Jacobsen, R. G.; Ji, W.; Kamdin, K.; Kazkaz, K.; Khaitan, D.; Knoche, R.; Lenardo, B. G.; Lesko, K. T.; Liao, J.; Lindote, A.; Lopes, M. I.; Manalaysay, A.; Mannino, R. L.; Marzioni, M. F.; McKinsey, D. N.; Mei, D.-M.; Mock, J.; Moongweluwan, M.; Morad, J. A.; Murphy, A. St. J.; Nehrkorn, C.; Nelson, H. N.; Neves, F.; O'Sullivan, K.; Oliver-Mallory, K. C.; Palladino, K. J.; Pease, E. K.; Rhyne, C.; Shaw, S.; Shutt, T. A.; Silva, C.; Solmaz, M.; Solovov, V. N.; Sorensen, P.; Sumner, T. J.; Szydagis, M.; Taylor, D. J.; Taylor, W. C.; Tennyson, B. P.; Terman, P. A.; Tiedt, D. R.; To, W. H.; Tripathi, M.; Tvrznikova, L.; Utku, U.; Uvarov, S.; Velan, V.; Verbus, J. R.; Webb, R. C.; White, J. T.; Whitis, T. J.; Witherell, M. S.; Wolfs, F. L. H.; Xu, J.; Yazdani, K.; Young, S. K.; Zhang, C.; LUX Collaboration

    2018-06-01

    Weakly interacting massive particles (WIMPs) are a leading candidate for dark matter and are expected to produce nuclear recoil (NR) events within liquid xenon time-projection chambers. We present a measurement of the scintillation timing characteristics of liquid xenon in the LUX dark matter detector and develop a pulse shape discriminant to be used for particle identification. To accurately measure the timing characteristics, we develop a template-fitting method to reconstruct the detection times of photons. Analyzing calibration data collected during the 2013-2016 LUX WIMP search, we provide a new measurement of the singlet-to-triplet scintillation ratio for electron recoils (ER) below 46 keV, and we make, to our knowledge, a first-ever measurement of the NR singlet-to-triplet ratio at recoil energies below 74 keV. We exploit the difference of the photon time spectra for NR and ER events by using a prompt fraction discrimination parameter, which is optimized using calibration data to have the least number of ER events that occur in a 50% NR acceptance region. We then demonstrate how this discriminant can be used in conjunction with the charge-to-light discrimination to possibly improve the signal-to-noise ratio for nuclear recoils.

  1. FPGA-based trigger system for the LUX dark matter experiment

    NASA Astrophysics Data System (ADS)

    Akerib, D. S.; Araújo, H. M.; Bai, X.; Bailey, A. J.; Balajthy, J.; Beltrame, P.; Bernard, E. P.; Bernstein, A.; Biesiadzinski, T. P.; Boulton, E. M.; Bradley, A.; Bramante, R.; Cahn, S. B.; Carmona-Benitez, M. C.; Chan, C.; Chapman, J. J.; Chiller, A. A.; Chiller, C.; Currie, A.; Cutter, J. E.; Davison, T. J. R.; de Viveiros, L.; Dobi, A.; Dobson, J. E. Y.; Druszkiewicz, E.; Edwards, B. N.; Faham, C. H.; Fiorucci, S.; Gaitskell, R. J.; Gehman, V. M.; Ghag, C.; Gibson, K. R.; Gilchriese, M. G. D.; Hall, C. R.; Hanhardt, M.; Haselschwardt, S. J.; Hertel, S. A.; Hogan, D. P.; Horn, M.; Huang, D. Q.; Ignarra, C. M.; Ihm, M.; Jacobsen, R. G.; Ji, W.; Kazkaz, K.; Khaitan, D.; Knoche, R.; Larsen, N. A.; Lee, C.; Lenardo, B. G.; Lesko, K. T.; Lindote, A.; Lopes, M. I.; Malling, D. C.; Manalaysay, A. G.; Mannino, R. L.; Marzioni, M. F.; McKinsey, D. N.; Mei, D.-M.; Mock, J.; Moongweluwan, M.; Morad, J. A.; Murphy, A. St. J.; Nehrkorn, C.; Nelson, H. N.; Neves, F.; O`Sullivan, K.; Oliver-Mallory, K. C.; Ott, R. A.; Palladino, K. J.; Pangilinan, M.; Pease, E. K.; Phelps, P.; Reichhart, L.; Rhyne, C.; Shaw, S.; Shutt, T. A.; Silva, C.; Skulski, W.; Solovov, V. N.; Sorensen, P.; Stephenson, S.; Sumner, T. J.; Szydagis, M.; Taylor, D. J.; Taylor, W.; Tennyson, B. P.; Terman, P. A.; Tiedt, D. R.; To, W. H.; Tripathi, M.; Tvrznikova, L.; Uvarov, S.; Verbus, J. R.; Webb, R. C.; White, J. T.; Whitis, T. J.; Witherell, M. S.; Wolfs, F. L. H.; Yin, J.; Young, S. K.; Zhang, C.

    2016-05-01

    LUX is a two-phase (liquid/gas) xenon time projection chamber designed to detect nuclear recoils resulting from interactions with dark matter particles. Signals from the detector are processed with an FPGA-based digital trigger system that analyzes the incoming data in real-time, with just a few microsecond latency. The system enables first pass selection of events of interest based on their pulse shape characteristics and 3D localization of the interactions. It has been shown to be > 99 % efficient in triggering on S2 signals induced by only few extracted liquid electrons. It is continuously and reliably operating since its full underground deployment in early 2013. This document is an overview of the systems capabilities, its inner workings, and its performance.

  2. Little Higgs dark matter after PandaX-II/LUX-2016 and LHC Run-1

    NASA Astrophysics Data System (ADS)

    Wu, Lei; Yang, Bingfang; Zhang, Mengchao

    2016-12-01

    In the Littlest Higgs model with T-parity (LHT), the T-odd heavy photon ( A H ) is weakly interacting and can play the role of dark matter. We investigate the lower limit on the mass of A H dark matter under the constraints from Higgs data, EWPOs, R b , Planck 2015 dark matter relic abundance, PandaX-II/LUX 2016 direct detections and LHC-8 TeV monojet results. We find that (1) Higgs data, EWPOs and R b can exclude the mass of A H up to 99 GeV. To produce the correct dark matter relic abundance, A H has to co-annihilate with T-odd quarks ( q H ) or leptons ( ℓ H ); (2) the LUX (PandaX-II) 2016 data can further exclude {m}_{A_H} < 380(270) GeV for ℓ H - A H co-annihilation and {m}_{A_H} < 350(240) GeV for q H - A H co-annihilation; (3) LHC-8 TeV monojet result can give a strong lower limit, {m}_{A_H} > 540 GeV, for q H - A H co-annihilation; (4) future XENON1T(2017) experiment can fully cover the parameter space of ℓ H - A H co-annihilation and will push the lower limit of {m}_{A_H} up to about 640 GeV for q H - A H co-annihilation.

  3. High Voltage Tests in the LUX-ZEPLIN System Test

    NASA Astrophysics Data System (ADS)

    Whitis, Thomas; Lux-Zeplin Collaboration

    2016-03-01

    The LUX-ZEPLIN (LZ) project is a dark matter direct detection experiment using liquid xenon. The detector is a time projection chamber (TPC) requiring the establishment of a large electric field inside of the detector in order to drift ionization electrons. Historically, many xenon TPC designs have been unable to reach their design fields due to light production and breakdown. The LZ System Test is scaled so that with a cathode voltage of -50 kV, it will have the fields that will be seen in the LZ detector at -100 kV. It will use a fully instrumented but scaled-down version of the LZ TPC design with a vessel set and gas system designed for quick turnaround, allowing for iterative modifications to the TPC prototype and instrumentation. This talk will present results from the high voltage tests performed during the first runs of the LZ System Test.

  4. FPGA-based trigger system for the LUX dark matter experiment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Akerib, D. S.; Araújo, H. M.; Bai, X.

    LUX is a two-phase (liquid/gas) xenon time projection chamber designed to detect nuclear recoils resulting from interactions with dark matter particles. Signals from the detector are processed with an FPGA-based digital trigger system that analyzes the incoming data in real-time, with just a few microsecond latency. The system enables first pass selection of events of interest based on their pulse shape characteristics and 3D localization of the interactions. It has been shown to be >99% efficient in triggering on S2 signals induced by only few extracted liquid electrons. It is continuously and reliably operating since its full underground deployment inmore » early 2013. This document is an overview of the systems capabilities, its inner workings, and its performance.« less

  5. FPGA-based trigger system for the LUX dark matter experiment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Akerib, D. S.; Araújo, H. M.; Bai, X.

    We present that LUX is a two-phase (liquid/gas) xenon time projection chamber designed to detect nuclear recoils resulting from interactions with dark matter particles. Signals from the detector are processed with an FPGA-based digital trigger system that analyzes the incoming data in real-time, with just a few microsecond latency. The system enables first pass selection of events of interest based on their pulse shape characteristics and 3D localization of the interactions. It has been shown to be > 99% efficient in triggering on S2 signals induced by only few extracted liquid electrons. It is continuously and reliably operating since itsmore » full underground deployment in early 2013. Finally, this document is an overview of the systems capabilities, its inner workings, and its performance.« less

  6. FPGA-based trigger system for the LUX dark matter experiment

    DOE PAGES

    Akerib, D. S.; Araújo, H. M.; Bai, X.; ...

    2016-02-17

    We present that LUX is a two-phase (liquid/gas) xenon time projection chamber designed to detect nuclear recoils resulting from interactions with dark matter particles. Signals from the detector are processed with an FPGA-based digital trigger system that analyzes the incoming data in real-time, with just a few microsecond latency. The system enables first pass selection of events of interest based on their pulse shape characteristics and 3D localization of the interactions. It has been shown to be > 99% efficient in triggering on S2 signals induced by only few extracted liquid electrons. It is continuously and reliably operating since itsmore » full underground deployment in early 2013. Finally, this document is an overview of the systems capabilities, its inner workings, and its performance.« less

  7. Harmonic cascade FEL designs for LUX

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Penn, G.; Reinsch, M.; Wurtele, J.

    LUX is a design concept for an ultrafast X-ray science facility, based on an electron beam accelerated to GeV energies in are circulating linac. Included in the design are short duration (200 fs or shorter FWHM) light sources using multiple stages of higher harmonic generation, seeded by a 200-250 nm laser of similar duration. This laser modulates the energy of a group of electrons within the electron bunch; this section of the electron bunch then produces radiation at a higher harmonic after entering a second, differently tuned undulator. Repeated stages in a cascade yield increasing photon energies up to 1more » keV. Most of the undulators in the cascade operate in the low-gain FEL regime. Harmonic cascades have been designed for each pass of the recirculating linac up to a final electron beam energy of 3.1 GeV. For a given cascade, the photon energy can be selected over a wide range by varying the seed laser frequency and the field strength in the undulators. We present simulation results using the codes GENESIS and GINGER, as well as the results of analytical models which predict FEL performance. We discuss lattice considerations pertinent for harmonic cascade FELs, as well as sensitivity studies and requirements on the electron beam.« less

  8. Results on the Spin-Dependent Scattering of Weakly Interacting Massive Particles on Nucleons from the Run 3 Data of the LUX Experiment

    NASA Astrophysics Data System (ADS)

    Akerib, D. S.; Araújo, H. M.; Bai, X.; Bailey, A. J.; Balajthy, J.; Beltrame, P.; Bernard, E. P.; Bernstein, A.; Biesiadzinski, T. P.; Boulton, E. M.; Bradley, A.; Bramante, R.; Cahn, S. B.; Carmona-Benitez, M. C.; Chan, C.; Chapman, J. J.; Chiller, A. A.; Chiller, C.; Currie, A.; Cutter, J. E.; Davison, T. J. R.; de Viveiros, L.; Dobi, A.; Dobson, J. E. Y.; Druszkiewicz, E.; Edwards, B. N.; Faham, C. H.; Fiorucci, S.; Gaitskell, R. J.; Gehman, V. M.; Ghag, C.; Gibson, K. R.; Gilchriese, M. G. D.; Hall, C. R.; Hanhardt, M.; Haselschwardt, S. J.; Hertel, S. A.; Hogan, D. P.; Horn, M.; Huang, D. Q.; Ignarra, C. M.; Ihm, M.; Jacobsen, R. G.; Ji, W.; Kazkaz, K.; Khaitan, D.; Knoche, R.; Larsen, N. A.; Lee, C.; Lenardo, B. G.; Lesko, K. T.; Lindote, A.; Lopes, M. I.; Malling, D. C.; Manalaysay, A.; Mannino, R. L.; Marzioni, M. F.; McKinsey, D. N.; Mei, D.-M.; Mock, J.; Moongweluwan, M.; Morad, J. A.; Murphy, A. St. J.; Nehrkorn, C.; Nelson, H. N.; Neves, F.; O'Sullivan, K.; Oliver-Mallory, K. C.; Ott, R. A.; Palladino, K. J.; Pangilinan, M.; Pease, E. K.; Phelps, P.; Reichhart, L.; Rhyne, C.; Shaw, S.; Shutt, T. A.; Silva, C.; Solovov, V. N.; Sorensen, P.; Stephenson, S.; Sumner, T. J.; Szydagis, M.; Taylor, D. J.; Taylor, W.; Tennyson, B. P.; Terman, P. A.; Tiedt, D. R.; To, W. H.; Tripathi, M.; Tvrznikova, L.; Uvarov, S.; Verbus, J. R.; Webb, R. C.; White, J. T.; Whitis, T. J.; Witherell, M. S.; Wolfs, F. L. H.; Yazdani, K.; Young, S. K.; Zhang, C.; LUX Collaboration

    2016-04-01

    We present experimental constraints on the spin-dependent WIMP (weakly interacting massive particle)-nucleon elastic cross sections from LUX data acquired in 2013. LUX is a dual-phase xenon time projection chamber operating at the Sanford Underground Research Facility (Lead, South Dakota), which is designed to observe the recoil signature of galactic WIMPs scattering from xenon nuclei. A profile likelihood ratio analysis of 1.4 ×104 kg day of fiducial exposure allows 90% C.L. upper limits to be set on the WIMP-neutron (WIMP-proton) cross section of σn=9.4 ×10-41 cm2 (σp=2.9 ×10-39 cm2 ) at 33 GeV /c2 . The spin-dependent WIMP-neutron limit is the most sensitive constraint to date.

  9. The natural furanone (5Z)-4-bromo-5-(bromomethylene)-3-butyl-2(5H)-furanone disrupts quorum sensing-regulated gene expression in Vibrio harveyi by decreasing the DNA-binding activity of the transcriptional regulator protein luxR.

    PubMed

    Defoirdt, Tom; Miyamoto, Carol M; Wood, Thomas K; Meighen, Edward A; Sorgeloos, Patrick; Verstraete, Willy; Bossier, Peter

    2007-10-01

    This study aimed at getting a deeper insight in the molecular mechanism by which the natural furanone (5Z)-4-bromo-5-(bromomethylene)-3-butyl-2(5H)-furanone disrupts quorum sensing in Vibrio harveyi. Bioluminescence experiments with signal molecule receptor double mutants revealed that the furanone blocks all three channels of the V. harveyi quorum sensing system. In further experiments using mutants with mutations in the quorum sensing signal transduction pathway, the compound was found to block quorum sensing-regulated bioluminescence by interacting with a component located downstream of the Hfq protein. Furthermore, reverse transcriptase real-time polymerase chain reaction with specific primers showed that there was no effect of the furanone on luxR(Vh) mRNA levels in wild-type V. harveyi cells. In contrast, mobility shift assays showed that in the presence of the furanone, significantly lower levels of the LuxR(Vh) response regulator protein were able to bind to its target promoter sequences in wild-type V. harveyi. Finally, tests with purified LuxR(Vh) protein also showed less shifts with furanone-treated LuxR(Vh), whereas the LuxR(Vh) concentration was found not to be altered by the furanone (as determined by SDS-PAGE). Therefore, our data indicate that the furanone blocks quorum sensing in V. harveyi by rendering the quorum sensing master regulator protein LuxR(Vh) unable to bind to the promoter sequences of quorum sensing-regulated genes.

  10. D-D Neutron Generator Calibrations and Hardware in the LUX-ZEPLIN Dark Matter Search Experiment

    NASA Astrophysics Data System (ADS)

    Taylor, Will; Lux-Zeplin Collaboration

    2016-03-01

    The LUX-ZEPLIN (LZ) dark matter search experiment will be a two-phase liquid/gas xenon time projection chamber with 7 tonnes of active liquid xenon (LXe) located at the 4850 ft level of the Sanford Underground Research Facility in Lead, SD. LZ will utilize an in-situ, absolute calibration of nuclear recoils (NR) in LXe using mono-energetic 2.45 MeV neutrons produced by a D-D neutron generator. This technique was used in the LUX detector to measured the NR charge yield in LXe (Qy) to 0.7 keV recoil energy and the NR light yield in LXe (Ly) to recoil energies of 1.1 keV - both of which were the lowest energy measurements achieved in the field. These absolute, ultra-low energy calibrations of the NR signal yields in LXe provide clear measurements of the detector response used for the WIMP search analysis. The improvements made for LZ will include shorter neutron pulse times, multiple neutron conduit configurations, and lower energy neutrons. The upgrades allow for even lower energy measurements of the nuclear recoil response in LXe and an independent measurement of Ly, as well as providing less uncertainty in energy reconstruction. In addition to discussing the physics of the neutron calibrations, I will describe the hardware systems used to implement them.

  11. 49 CFR Table 1 to Subpart B of... - Minimum Coefficient of Retroreflection (RA) (in Candela/Lux/Meter2) Requirement for...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...) 1 Table 1 to Subpart B of Part 224 Transportation Other Regulations Relating to Transportation... ROLLING STOCK Application, Inspection, and Maintenance of Retroreflective Material Pt. 224, Subpt. B, Table 1 Table 1 to Subpart B of Part 224—Minimum Coefficient of Retroreflection (RA) (in Candela/Lux...

  12. 49 CFR Table 1 to Subpart B of... - Minimum Coefficient of Retroreflection (RA) (in Candela/Lux/Meter2) Requirement for...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...) 1 Table 1 to Subpart B of Part 224 Transportation Other Regulations Relating to Transportation... ROLLING STOCK Application, Inspection, and Maintenance of Retroreflective Material Pt. 224, Subpt. B, Table 1 Table 1 to Subpart B of Part 224—Minimum Coefficient of Retroreflection (RA) (in Candela/Lux...

  13. New LUX result constrains exotic quark mediators with the vector dark matter

    NASA Astrophysics Data System (ADS)

    Chen, Chuan-Ren; Li, Ming-Jie

    2016-12-01

    The scenario of the compressed mass spectrum between heavy quark and dark matter is a challenge for LHC searches. However, the elastic scattering cross-section between dark matter and nuclei in dark matter direct detection experiments can be enhanced with nearly degenerate masses between heavy quarks and dark matter. In this paper, we illustrate such scenario with a vector dark matter, using the latest result from LUX 2016. The mass constraints on heavy quarks can be more stringent than current limits from LHC, unless the coupling strength is very small. However, the compress mass spectrum with allowed tiny coupling strength makes the decay lifetime of heavy quarks longer than the timescale of QCD hadronization.

  14. VanT, a Homologue of Vibrio harveyi LuxR, Regulates Serine, Metalloprotease, Pigment, and Biofilm Production in Vibrio anguillarum

    PubMed Central

    Croxatto, Antony; Chalker, Victoria J.; Lauritz, Johan; Jass, Jana; Hardman, Andrea; Williams, Paul; Cámara, Miguel; Milton, Debra L.

    2002-01-01

    Vibrio anguillarum possesses at least two N-acylhomoserine lactone (AHL) quorum-sensing circuits, one of which is related to the luxMN system of Vibrio harveyi. In this study, we have cloned an additional gene of this circuit, vanT, encoding a V. harveyi LuxR-like transcriptional regulator. A V. anguillarum ΔvanT null mutation resulted in a significant decrease in total protease activity due to loss of expression of the metalloprotease EmpA, but no changes in either AHL production or virulence. Additional genes positively regulated by VanT were identified from a plasmid-based gene library fused to a promoterless lacZ. Three lacZ fusions (serA::lacZ, hpdA-hgdA::lacZ, and sat-vps73::lacZ) were identified which exhibited decreased expression in the ΔvanT strain. SerA is similar to 3-phosphoglycerate dehydrogenases and catalyzes the first step in the serine-glycine biosynthesis pathway. HgdA has identity with homogentisate dioxygenases, and HpdA is homologous to 4-hydroxyphenylpyruvate dioxygenases (HPPDs) involved in pigment production. V. anguillarum strains require an active VanT to produce high levels of an l-tyrosine-induced brown color via HPPD, suggesting that VanT controls pigment production. Vps73 and Sat are related to Vibrio cholerae proteins encoded within a DNA locus required for biofilm formation. A V. anguillarum ΔvanT mutant and a mutant carrying a polar mutation in the sat-vps73 DNA locus were shown to produce defective biofilms. Hence, a new member of the V. harveyi LuxR transcriptional activator family has been characterized in V. anguillarum that positively regulates serine, metalloprotease, pigment, and biofilm production. PMID:11872713

  15. VanT, a homologue of Vibrio harveyi LuxR, regulates serine, metalloprotease, pigment, and biofilm production in Vibrio anguillarum.

    PubMed

    Croxatto, Antony; Chalker, Victoria J; Lauritz, Johan; Jass, Jana; Hardman, Andrea; Williams, Paul; Cámara, Miguel; Milton, Debra L

    2002-03-01

    Vibrio anguillarum possesses at least two N-acylhomoserine lactone (AHL) quorum-sensing circuits, one of which is related to the luxMN system of Vibrio harveyi. In this study, we have cloned an additional gene of this circuit, vanT, encoding a V. harveyi LuxR-like transcriptional regulator. A V. anguillarum Delta vanT null mutation resulted in a significant decrease in total protease activity due to loss of expression of the metalloprotease EmpA, but no changes in either AHL production or virulence. Additional genes positively regulated by VanT were identified from a plasmid-based gene library fused to a promoterless lacZ. Three lacZ fusions (serA::lacZ, hpdA-hgdA::lacZ, and sat-vps73::lacZ) were identified which exhibited decreased expression in the Delta vanT strain. SerA is similar to 3-phosphoglycerate dehydrogenases and catalyzes the first step in the serine-glycine biosynthesis pathway. HgdA has identity with homogentisate dioxygenases, and HpdA is homologous to 4-hydroxyphenylpyruvate dioxygenases (HPPDs) involved in pigment production. V. anguillarum strains require an active VanT to produce high levels of an L-tyrosine-induced brown color via HPPD, suggesting that VanT controls pigment production. Vps73 and Sat are related to Vibrio cholerae proteins encoded within a DNA locus required for biofilm formation. A V. anguillarum Delta vanT mutant and a mutant carrying a polar mutation in the sat-vps73 DNA locus were shown to produce defective biofilms. Hence, a new member of the V. harveyi LuxR transcriptional activator family has been characterized in V. anguillarum that positively regulates serine, metalloprotease, pigment, and biofilm production.

  16. Postmortem Photonic Imaging of Lux-Modified Salmonella Typhimuium Within the Gastrointestinal Tract of Swine Following Oral Inoculation In Vivo

    USDA-ARS?s Scientific Manuscript database

    The study objective was to monitor Salmonella progression by photonic detection through segments of the gastrointestinal tract after oral inoculation. Pigs (~80 kg) were inoculated orally with 3.1 or 4.1 x 1010 cfu of Salmonella Typhimurium transformed with plasmid pAK1-lux for a 6-h (n = 6) or 12-h...

  17. Results on the Spin-Dependent Scattering of Weakly Interacting Massive Particles on Nucleons from the Run 3 Data of the LUX Experiment.

    PubMed

    Akerib, D S; Araújo, H M; Bai, X; Bailey, A J; Balajthy, J; Beltrame, P; Bernard, E P; Bernstein, A; Biesiadzinski, T P; Boulton, E M; Bradley, A; Bramante, R; Cahn, S B; Carmona-Benitez, M C; Chan, C; Chapman, J J; Chiller, A A; Chiller, C; Currie, A; Cutter, J E; Davison, T J R; de Viveiros, L; Dobi, A; Dobson, J E Y; Druszkiewicz, E; Edwards, B N; Faham, C H; Fiorucci, S; Gaitskell, R J; Gehman, V M; Ghag, C; Gibson, K R; Gilchriese, M G D; Hall, C R; Hanhardt, M; Haselschwardt, S J; Hertel, S A; Hogan, D P; Horn, M; Huang, D Q; Ignarra, C M; Ihm, M; Jacobsen, R G; Ji, W; Kazkaz, K; Khaitan, D; Knoche, R; Larsen, N A; Lee, C; Lenardo, B G; Lesko, K T; Lindote, A; Lopes, M I; Malling, D C; Manalaysay, A; Mannino, R L; Marzioni, M F; McKinsey, D N; Mei, D-M; Mock, J; Moongweluwan, M; Morad, J A; Murphy, A St J; Nehrkorn, C; Nelson, H N; Neves, F; O'Sullivan, K; Oliver-Mallory, K C; Ott, R A; Palladino, K J; Pangilinan, M; Pease, E K; Phelps, P; Reichhart, L; Rhyne, C; Shaw, S; Shutt, T A; Silva, C; Solovov, V N; Sorensen, P; Stephenson, S; Sumner, T J; Szydagis, M; Taylor, D J; Taylor, W; Tennyson, B P; Terman, P A; Tiedt, D R; To, W H; Tripathi, M; Tvrznikova, L; Uvarov, S; Verbus, J R; Webb, R C; White, J T; Whitis, T J; Witherell, M S; Wolfs, F L H; Yazdani, K; Young, S K; Zhang, C

    2016-04-22

    We present experimental constraints on the spin-dependent WIMP (weakly interacting massive particle)-nucleon elastic cross sections from LUX data acquired in 2013. LUX is a dual-phase xenon time projection chamber operating at the Sanford Underground Research Facility (Lead, South Dakota), which is designed to observe the recoil signature of galactic WIMPs scattering from xenon nuclei. A profile likelihood ratio analysis of 1.4×10^{4}  kg day of fiducial exposure allows 90% C.L. upper limits to be set on the WIMP-neutron (WIMP-proton) cross section of σ_{n}=9.4×10^{-41}  cm^{2} (σ_{p}=2.9×10^{-39}  cm^{2}) at 33  GeV/c^{2}. The spin-dependent WIMP-neutron limit is the most sensitive constraint to date.

  18. Results on the spin-dependent scattering of weakly interacting massive particles on nucleons from the Run 3 Data of the LUX Experiment

    DOE PAGES

    Akerib, D. S.

    2016-04-20

    Here, we present experimental constraints on the spin-dependent WIMP (weakly interacting massive particle)-nucleon elastic cross sections from LUX data acquired in 2013. LUX is a dual-phase xenon time projection chamber operating at the Sanford Underground Research Facility (Lead, South Dakota), which is designed to observe the recoil signature of galactic WIMPs scattering from xenon nuclei. A profile likelihood ratio analysis of 1.4 × 10 4 kg day of fiducial exposure allows 90% C.L. upper limits to be set on the WIMP-neutron (WIMP-proton) cross section of σ n = 9.4 × 10 –41 cm 2 (σ p = 2.9 × 10more » –39 cm 2) at 33 GeV/c 2. The spin-dependent WIMP-neutron limit is the most sensitive constraint to date.« less

  19. Flux calculations and trends of atmospheric pollutants in the BeNeLux/Rhein-Ruhr area from 2000 - 2009

    NASA Astrophysics Data System (ADS)

    Jakobs, Hermann; Memmesheimer, Michael

    2010-05-01

    The BeNeLux/Rhine-Ruhr area is a strongly industrialized region in Central Europe with high population density. As a part of it, Rhine-Ruhr with about 10 Million inhabitants is one of the regions in Europe which has a megacity character with respect to population density, traffic, industry and environmental issues. The main centre of European steel production and the biggest inland port of the world are located in Duisburg, one of the major cities in the Rhine-Ruhr area. Together with the nearby urban agglomerations of the Benelux area, e.g., Brussels, Amsterdam and Rotterdam as one of the most important sea harbours of the world, it is one of the regions in Europe which is most heavily burdened with air pollutants like ozone, NO2 and PM10. One major goal with respect to air quality survey within megacities is their temporal variability and the ingoing and outgoing fluxes. Therefore a whole decade (years 2000 - 2009) was simulated with the regional scale model EURAD (European Air pollution Dispersion Model). The model calculates the transport, chemical transformations and deposition of air pollutants in the troposphere from the surface up to about 16 km. Meteorological fields are provided by the meteorological model MM5. The flux and trend calculations are restricted to two areas: the small BeNeLux-Ruhr domain (longitude: 2 deg 30 min E - 8 deg 00 min E, latitude: 49 deg 20 min N - 53 deg 40 min N) and a big BeNeLux-Ruhr domain (longitude: 01 deg 00 min W - 08 deg 00 min E, 48 deg 00 min N - 54 deg 00 min N) including the cities Paris and London. This work was done within the framework of the FP7 project CityZen. Yearly in- and outflow fluxes were calculated at the borders of the megacity domains and compared with respect of interanual variability. In addition annual means and number of exceedances of limit values are compared for the major hot spots within the mentioned domains.

  20. N-Acetylglucosamine Inhibits LuxR, LasR and CviR Based Quorum Sensing Regulated Gene Expression Levels

    PubMed Central

    Kimyon, Önder; Ulutürk, Zehra İ.; Nizalapur, Shashidhar; Lee, Matthew; Kutty, Samuel K.; Beckmann, Sabrina; Kumar, Naresh; Manefield, Mike

    2016-01-01

    N-acetyl glucosamine, the monomer of chitin, is an abundant source of carbon and nitrogen in nature as it is the main component and breakdown product of many structural polymers. Some bacteria use N-acyl-L-homoserine lactone (AHL) mediated quorum sensing (QS) to regulate chitinase production in order to catalyze the cleavage of chitin polymers into water soluble N-acetyl-D-glucosamine (NAG) monomers. In this study, the impact of NAG on QS activities of LuxR, LasR, and CviR regulated gene expression was investigated by examining the effect of NAG on QS regulated green fluorescent protein (GFP), violacein and extracellular chitinase expression. It was discovered that NAG inhibits AHL dependent gene transcription in AHL reporter strains within the range of 50–80% reduction at low millimolar concentrations (0.25–5 mM). Evidence is presented supporting a role for both competitive inhibition at the AHL binding site of LuxR type transcriptional regulators and catabolite repression. Further, this study shows that NAG down-regulates CviR induced violacein production while simultaneously up-regulating CviR dependent extracellular enzymes, suggesting that an unknown NAG dependent regulatory component influences phenotype expression. The quorum sensing inhibiting activity of NAG also adds to the list of compounds with known quorum sensing inhibiting activities. PMID:27602027

  1. A LuxR homolog in a cottonwood tree endophyte that activates gene expression in response to a plant signal or specific peptides

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schaefer, Amy L.; Oda, Yasuhiro; Coutinho, Bruna Goncalves

    Homologs of the LuxR acyl-homoserine lactone (AHL) quorum-sensing signal receptor are prevalent in Proteobacteria isolated from roots of the Eastern cottonwood tree, Populus deltoides. Many of these isolates possess an orphan LuxR homolog, closely related to OryR from the rice pathogen Xanthomonas oryzae. OryR does not respond to AHL signals but, instead, responds to an unknown plant compound. We discovered an OryR homolog, PipR, in the cottonwood endophyte Pseudomonas sp. strain GM79. The genes adjacent to pipR encode a predicted ATP-binding cassette (ABC) peptide transporter and peptidases. We purified the putative peptidases, PipA and AapA, and confirmed their predicted activities.more » A transcriptional pipA-gfp reporter was responsive to PipR in the presence of plant leaf macerates, but it was not influenced by AHLs, similar to findings with OryR. We found that PipR also responded to protein hydrolysates to activate pipA-gfp expression. Among many peptides tested, the tripeptide Ser-His-Ser showed inducer activity but at relatively high concentrations. An ABC peptide transporter mutant failed to respond to leaf macerates, peptone, or Ser-His-Ser, while peptidase mutants expressed higher-than-wild-type levels of pipA-gfp in response to any of these signals. Our studies are consistent with a model where active transport of a peptidelike signal is required for the signal to interact with PipR, which then activates peptidase gene expression. As a result, the identification of a peptide ligand for PipR sets the stage to identify plant-derived signals for the OryR family of orphan LuxR proteins.« less

  2. A LuxR homolog in a cottonwood tree endophyte that activates gene expression in response to a plant signal or specific peptides

    DOE PAGES

    Schaefer, Amy L.; Oda, Yasuhiro; Coutinho, Bruna Goncalves; ...

    2016-08-02

    Homologs of the LuxR acyl-homoserine lactone (AHL) quorum-sensing signal receptor are prevalent in Proteobacteria isolated from roots of the Eastern cottonwood tree, Populus deltoides. Many of these isolates possess an orphan LuxR homolog, closely related to OryR from the rice pathogen Xanthomonas oryzae. OryR does not respond to AHL signals but, instead, responds to an unknown plant compound. We discovered an OryR homolog, PipR, in the cottonwood endophyte Pseudomonas sp. strain GM79. The genes adjacent to pipR encode a predicted ATP-binding cassette (ABC) peptide transporter and peptidases. We purified the putative peptidases, PipA and AapA, and confirmed their predicted activities.more » A transcriptional pipA-gfp reporter was responsive to PipR in the presence of plant leaf macerates, but it was not influenced by AHLs, similar to findings with OryR. We found that PipR also responded to protein hydrolysates to activate pipA-gfp expression. Among many peptides tested, the tripeptide Ser-His-Ser showed inducer activity but at relatively high concentrations. An ABC peptide transporter mutant failed to respond to leaf macerates, peptone, or Ser-His-Ser, while peptidase mutants expressed higher-than-wild-type levels of pipA-gfp in response to any of these signals. Our studies are consistent with a model where active transport of a peptidelike signal is required for the signal to interact with PipR, which then activates peptidase gene expression. As a result, the identification of a peptide ligand for PipR sets the stage to identify plant-derived signals for the OryR family of orphan LuxR proteins.« less

  3. POLYPHYLY OF NON-BIOLUMINESCENT VIBRIO FISCHERI SHARING A LUX-LOCUS DELETION

    PubMed Central

    Wollenberg, M.S.; Preheim, S.P.; Polz, M.F.; Ruby, E. G.

    2013-01-01

    SUMMARY This study reports the first description and molecular characterization of naturally occurring, non-bioluminescent strains of V. fischeri. These ‘dark’ V. fischeri strains remained non-bioluminescent even after treatment with both autoinducer and aldehyde, substrate additions that typically maximize light-production in dim strains of luminous bacteria. Surprisingly, the entire lux locus (8 genes) was absent in over 97% of these dark V. fischeri strains. Although these strains were all collected from a Massachusetts (USA) estuary in 2007, phylogenetic reconstructions allowed us to reject the hypothesis that these newly described non-bioluminescent strains exhibit monophyly within the V. fischeri clade. These dark strains exhibited a competitive disadvantage against native bioluminescent strains when colonizing the light organ of the model V. fischeri host, the Hawaiian bobtail squid Euprymna scolopes. Significantly, we believe that the data collected in this study may suggest the first observation of a functional, parallel locus-deletion event among independent lineages of a non-pathogenic bacterial species. PMID:21980988

  4. Identification of Vibrio splendidus as a Member of the Planktonic Luminous Bacteria from the Persian Gulf and Kuwait Region with luxA Probes

    PubMed Central

    Nealson, K. H.; Wimpee, B.; Wimpee, C.

    1993-01-01

    Hybridization probes specific for the luxA genes of four groups of luminous bacteria were used to screen luminous isolates obtained from the Persian Gulf, near Al Khiran, Kuwait Nine of these isolates were identified as Vibrio harveyi, a commonly encountered planktonic isolate, while three others showed no hybridization to any of the four probes (V. harveyi, Vibrio fischeri, Photobacterium phosphoreum, or Photobacterium leiognathi) under high-stringency conditions. Polymerase chain reaction amplification was used to prepare a luxA probe against one of these isolates, K-1, and this probe was screened under high-stringency conditions against a collection of DNAs from luminous bacteria; it was found to hybridize specifically to the DNA of the species Vibrio splendidus. A probe prepared against the type strain of V. splendidus (ATCC 33369) was tested against the collection of luminous bacterial DNA preparations and against the Kuwait isolates and was found to hybridize only against the type strain and the three unidentified Kuwait isolates. Extensive taxonomic analysis by standard methods confirmed the identification of the 13 isolates. Images PMID:16349023

  5. Polyphyly of non-bioluminescent Vibrio fischeri sharing a lux-locus deletion.

    PubMed

    Wollenberg, M S; Preheim, S P; Polz, M F; Ruby, E G

    2012-03-01

    This study reports the first description and molecular characterization of naturally occurring, non-bioluminescent strains of Vibrio fischeri. These 'dark' V. fischeri strains remained non-bioluminescent even after treatment with both autoinducer and aldehyde, substrate additions that typically maximize light production in dim strains of luminous bacteria. Surprisingly, the entire lux locus (eight genes) was absent in over 97% of these dark V. fischeri strains. Although these strains were all collected from a Massachusetts (USA) estuary in 2007, phylogenetic reconstructions allowed us to reject the hypothesis that these newly described non-bioluminescent strains exhibit monophyly within the V. fischeri clade. These dark strains exhibited a competitive disadvantage against native bioluminescent strains when colonizing the light organ of the model V. fischeri host, the Hawaiian bobtail squid Euprymna scolopes. Significantly, we believe that the data collected in this study may suggest the first observation of a functional, parallel locus-deletion event among independent lineages of a non-pathogenic bacterial species. © 2011 Society for Applied Microbiology and Blackwell Publishing Ltd.

  6. EST databases and web tools for EST projects.

    PubMed

    Shen, Yao-Qing; O'Brien, Emmet; Koski, Liisa; Lang, B Franz; Burger, Gertraud

    2009-01-01

    This chapter outlines key considerations for constructing and implementing an EST database. Instead of showing the technological details step by step, emphasis is put on the design of an EST database suited to the specific needs of EST projects and how to choose the most suitable tools. Using TBestDB as an example, we illustrate the essential factors to be considered for database construction and the steps for data population and annotation. This process employs technologies such as PostgreSQL, Perl, and PHP to build the database and interface, and tools such as AutoFACT for data processing and annotation. We discuss these in comparison to other available technologies and tools, and explain the reasons for our choices.

  7. EST-PAC a web package for EST annotation and protein sequence prediction

    PubMed Central

    Strahm, Yvan; Powell, David; Lefèvre, Christophe

    2006-01-01

    With the decreasing cost of DNA sequencing technology and the vast diversity of biological resources, researchers increasingly face the basic challenge of annotating a larger number of expressed sequences tags (EST) from a variety of species. This typically consists of a series of repetitive tasks, which should be automated and easy to use. The results of these annotation tasks need to be stored and organized in a consistent way. All these operations should be self-installing, platform independent, easy to customize and amenable to using distributed bioinformatics resources available on the Internet. In order to address these issues, we present EST-PAC a web oriented multi-platform software package for expressed sequences tag (EST) annotation. EST-PAC provides a solution for the administration of EST and protein sequence annotations accessible through a web interface. Three aspects of EST annotation are automated: 1) searching local or remote biological databases for sequence similarities using Blast services, 2) predicting protein coding sequence from EST data and, 3) annotating predicted protein sequences with functional domain predictions. In practice, EST-PAC integrates the BLASTALL suite, EST-Scan2 and HMMER in a relational database system accessible through a simple web interface. EST-PAC also takes advantage of the relational database to allow consistent storage, powerful queries of results and, management of the annotation process. The system allows users to customize annotation strategies and provides an open-source data-management environment for research and education in bioinformatics. PMID:17147782

  8. Characterization of a chromosomally integrated luxCDABE marker for investigation of shiga toxin-producing Escherichia coli O91:H21 shedding in cattle

    NASA Astrophysics Data System (ADS)

    Hong, Yingying; Mathew, Alan G.

    2011-06-01

    Shiga toxin-producing Escherichia coli (STEC) O91:H21 has been recognized as a potential life-threatening foodborne pathogen and is commonly involved in human infections in European countries. Fecal shedding of the organism by cattle is considered to be the ultimate source for contaminations. Studies examining STEC shedding patterns often include inoculation of strains carrying antibiotic resistance makers for identifiable recovery. However, indigenous intestinal microflora exhibiting similar antibiotic resistance patterns can confound such studies. Such was the case in a study by our group when attempting to characterize shedding patterns of O91:H21 in calves. A chromosomally integrated bioluminescence marker using a luxCDABE cassette from Photorhabdus luminescens was developed in O91:H21 to overcome such shortcomings of antibiotic resistance markers during animal challenge experiment. The marker was validated in various aspects and was shown to have no impact on metabolic reactions, isotype virulence gene patterns, cost to growth, and additionally demonstrated high in vitro stability. Together, the results indicated that a chromosomally integrated luxCDABE based marker may be a superior system for the study of STEC colonization and shedding in cattle.

  9. 3D modeling of electric fields in the LUX detector

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Akerib, D. S.; Alsum, S.; Araújo, H. M.

    This work details the development of a three-dimensional (3D) electric field model for the LUX detector. The detector took data to search for weakly interacting massive particles (WIMPs) during two periods. After the first period completed, a time-varying non-uniform negative charge developed in the polytetrafluoroethylene (PTFE) panels that define the radial boundary of the detector's active volume. This caused electric field variations in the detector in time, depth and azimuth, generating an electrostatic radially-inward force on electrons on their way upward to the liquid surface. To map this behavior, 3D electric field maps of the detector's active volume were generatedmore » on a monthly basis. This was done by fitting a model built in COMSOL Multiphysics to the uniformly distributed calibration data that were collected on a regular basis. The modeled average PTFE charge density increased over the course of the exposure from -3.6 to -5.5 μC/m 2. Here, from our studies, we deduce that the electric field magnitude varied locally while the mean value of the field of ~200 V/cm remained constant throughout the exposure. As a result of this work the varying electric fields and their impact on event reconstruction and discrimination were successfully modeled.« less

  10. 3D modeling of electric fields in the LUX detector

    DOE PAGES

    Akerib, D. S.; Alsum, S.; Araújo, H. M.; ...

    2017-11-24

    This work details the development of a three-dimensional (3D) electric field model for the LUX detector. The detector took data to search for weakly interacting massive particles (WIMPs) during two periods. After the first period completed, a time-varying non-uniform negative charge developed in the polytetrafluoroethylene (PTFE) panels that define the radial boundary of the detector's active volume. This caused electric field variations in the detector in time, depth and azimuth, generating an electrostatic radially-inward force on electrons on their way upward to the liquid surface. To map this behavior, 3D electric field maps of the detector's active volume were generatedmore » on a monthly basis. This was done by fitting a model built in COMSOL Multiphysics to the uniformly distributed calibration data that were collected on a regular basis. The modeled average PTFE charge density increased over the course of the exposure from -3.6 to -5.5 μC/m 2. Here, from our studies, we deduce that the electric field magnitude varied locally while the mean value of the field of ~200 V/cm remained constant throughout the exposure. As a result of this work the varying electric fields and their impact on event reconstruction and discrimination were successfully modeled.« less

  11. 3D modeling of electric fields in the LUX detector

    NASA Astrophysics Data System (ADS)

    Akerib, D. S.; Alsum, S.; Araújo, H. M.; Bai, X.; Bailey, A. J.; Balajthy, J.; Beltrame, P.; Bernard, E. P.; Bernstein, A.; Biesiadzinski, T. P.; Boulton, E. M.; Brás, P.; Byram, D.; Cahn, S. B.; Carmona-Benitez, M. C.; Chan, C.; Currie, A.; Cutter, J. E.; Davison, T. J. R.; Dobi, A.; Druszkiewicz, E.; Edwards, B. N.; Fallon, S. R.; Fan, A.; Fiorucci, S.; Gaitskell, R. J.; Genovesi, J.; Ghag, C.; Gilchriese, M. G. D.; Hall, C. R.; Hanhardt, M.; Haselschwardt, S. J.; Hertel, S. A.; Hogan, D. P.; Horn, M.; Huang, D. Q.; Ignarra, C. M.; Jacobsen, R. G.; Ji, W.; Kamdin, K.; Kazkaz, K.; Khaitan, D.; Knoche, R.; Larsen, N. A.; Lenardo, B. G.; Lesko, K. T.; Lindote, A.; Lopes, M. I.; Manalaysay, A.; Mannino, R. L.; Marzioni, M. F.; McKinsey, D. N.; Mei, D.-M.; Mock, J.; Moongweluwan, M.; Morad, J. A.; Murphy, A. St. J.; Nehrkorn, C.; Nelson, H. N.; Neves, F.; O'Sullivan, K.; Oliver-Mallory, K. C.; Palladino, K. J.; Pease, E. K.; Rhyne, C.; Shaw, S.; Shutt, T. A.; Silva, C.; Solmaz, M.; Solovov, V. N.; Sorensen, P.; Sumner, T. J.; Szydagis, M.; Taylor, D. J.; Taylor, W. C.; Tennyson, B. P.; Terman, P. A.; Tiedt, D. R.; To, W. H.; Tripathi, M.; Tvrznikova, L.; Uvarov, S.; Velan, V.; Verbus, J. R.; Webb, R. C.; White, J. T.; Whitis, T. J.; Witherell, M. S.; Wolfs, F. L. H.; Xu, J.; Yazdani, K.; Young, S. K.; Zhang, C.

    2017-11-01

    This work details the development of a three-dimensional (3D) electric field model for the LUX detector. The detector took data to search for weakly interacting massive particles (WIMPs) during two periods. After the first period completed, a time-varying non-uniform negative charge developed in the polytetrafluoroethylene (PTFE) panels that define the radial boundary of the detector's active volume. This caused electric field variations in the detector in time, depth and azimuth, generating an electrostatic radially-inward force on electrons on their way upward to the liquid surface. To map this behavior, 3D electric field maps of the detector's active volume were generated on a monthly basis. This was done by fitting a model built in COMSOL Multiphysics to the uniformly distributed calibration data that were collected on a regular basis. The modeled average PTFE charge density increased over the course of the exposure from -3.6 to -5.5 μC/m2. From our studies, we deduce that the electric field magnitude varied locally while the mean value of the field of ~200 V/cm remained constant throughout the exposure. As a result of this work the varying electric fields and their impact on event reconstruction and discrimination were successfully modeled.

  12. Horse species symposium: a novel approach to monitoring pathogen progression during uterine and placental infection in the mare using bioluminescence imaging technology and lux-modified bacteria.

    PubMed

    Ryan, P L; Christiansen, D L; Hopper, R M; Walters, F K; Moulton, K; Curbelo, J; Greene, J M; Willard, S T

    2011-05-01

    Uterine and placental infections are the leading cause of abortion, stillbirth, and preterm delivery in the mare. Whereas uterine and placental infections in women have been studied extensively, a comprehensive examination of the pathogenic processes leading to this unsatisfactory pregnancy outcome in the mare has yet to be completed. Most information in the literature relating to late-term pregnancy loss in mares is based on retrospective studies of clinical cases submitted for necropsy. Here we report the development and application of a novel approach, whereby transgenically modified bacteria transformed with lux genes of Xenorhabdus luminescens or Photorhabdus luminescens origin and biophotonic imaging are utilized to better understand pathogen-induced preterm birth in late-term pregnant mares. This technology uses highly sensitive bioluminescence imaging camera systems to localize and monitor pathogen progression during tissue invasion by measuring the bioluminescent signatures emitted by the lux-modified pathogens. This method has an important advantage in that it allows for the potential tracking of pathogens in vivo in real time and over time, which was hitherto impossible. Although the application of this technology in domestic animals is in its infancy, investigators were successful in identifying the fetal lungs, sinuses, nares, urinary, and gastrointestinal systems as primary tissues for pathogen invasion after experimental infection of pregnant mares with lux-modified Escherichia coli. It is important that pathogens were not detected in other vital organs, such as the liver, brain, and cardiac system. Such precision in localizing sites of pathogen invasion provides potential application for this novel approach in the development of more targeted therapeutic interventions for pathogen-related diseases in the equine and other domestic species.

  13. Calibration, event reconstruction, data analysis, and limit calculation for the LUX dark matter experiment

    NASA Astrophysics Data System (ADS)

    Akerib, D. S.; Alsum, S.; Araújo, H. M.; Bai, X.; Bailey, A. J.; Balajthy, J.; Beltrame, P.; Bernard, E. P.; Bernstein, A.; Biesiadzinski, T. P.; Boulton, E. M.; Brás, P.; Byram, D.; Cahn, S. B.; Carmona-Benitez, M. C.; Chan, C.; Currie, A.; Cutter, J. E.; Davison, T. J. R.; Dobi, A.; Dobson, J. E. Y.; Druszkiewicz, E.; Edwards, B. N.; Faham, C. H.; Fallon, S. R.; Fan, A.; Fiorucci, S.; Gaitskell, R. J.; Gehman, V. M.; Genovesi, J.; Ghag, C.; Gilchriese, M. G. D.; Hall, C. R.; Hanhardt, M.; Haselschwardt, S. J.; Hertel, S. A.; Hogan, D. P.; Horn, M.; Huang, D. Q.; Ignarra, C. M.; Jacobsen, R. G.; Ji, W.; Kamdin, K.; Kazkaz, K.; Khaitan, D.; Knoche, R.; Larsen, N. A.; Lee, C.; Lenardo, B. G.; Lesko, K. T.; Lindote, A.; Lopes, M. I.; Manalaysay, A.; Mannino, R. L.; Marzioni, M. F.; McKinsey, D. N.; Mei, D.-M.; Mock, J.; Moongweluwan, M.; Morad, J. A.; Murphy, A. St. J.; Nehrkorn, C.; Nelson, H. N.; Neves, F.; O'Sullivan, K.; Oliver-Mallory, K. C.; Palladino, K. J.; Pease, E. K.; Reichhart, L.; Rhyne, C.; Shaw, S.; Shutt, T. A.; Silva, C.; Solmaz, M.; Solovov, V. N.; Sorensen, P.; Sumner, T. J.; Szydagis, M.; Taylor, D. J.; Taylor, W. C.; Tennyson, B. P.; Terman, P. A.; Tiedt, D. R.; To, W. H.; Tripathi, M.; Tvrznikova, L.; Uvarov, S.; Velan, V.; Verbus, J. R.; Webb, R. C.; White, J. T.; Whitis, T. J.; Witherell, M. S.; Wolfs, F. L. H.; Xu, J.; Yazdani, K.; Young, S. K.; Zhang, C.; LUX Collaboration

    2018-05-01

    The LUX experiment has performed searches for dark-matter particles scattering elastically on xenon nuclei, leading to stringent upper limits on the nuclear scattering cross sections for dark matter. Here, for results derived from 1.4 ×104 kg days of target exposure in 2013, details of the calibration, event-reconstruction, modeling, and statistical tests that underlie the results are presented. Detector performance is characterized, including measured efficiencies, stability of response, position resolution, and discrimination between electron- and nuclear-recoil populations. Models are developed for the drift field, optical properties, background populations, the electron- and nuclear-recoil responses, and the absolute rate of low-energy background events. Innovations in the analysis include in situ measurement of the photomultipliers' response to xenon scintillation photons, verification of fiducial mass with a low-energy internal calibration source, and new empirical models for low-energy signal yield based on large-sample, in situ calibrations.

  14. Regulation of a Glycerol-Induced Quinoprotein Alcohol Dehydrogenase by σ54 and a LuxR-Type Regulator in Azospirillum brasilense Sp7

    PubMed Central

    Singh, Vijay Shankar; Dubey, Ashutosh Prakash; Gupta, Ankush; Singh, Sudhir; Singh, Bhupendra Narain

    2017-01-01

    ABSTRACT Azospirillum brasilense Sp7 uses glycerol as a carbon source for growth and nitrogen fixation. When grown in medium containing glycerol as a source of carbon, it upregulates the expression of a protein which was identified as quinoprotein alcohol dehydrogenase (ExaA). Inactivation of exaA adversely affects the growth of A. brasilense on glycerol. A determination of the transcription start site of exaA revealed an RpoN-dependent −12/−24 promoter consensus. The expression of an exaA::lacZ fusion was induced maximally by glycerol and was dependent on σ54. Bioinformatic analysis of the sequence flanking the −12/−24 promoter revealed a 17-bp sequence motif with a dyad symmetry of 6 nucleotides upstream of the promoter, the disruption of which caused a drastic reduction in promoter activity. The electrophoretic mobility of a DNA fragment containing the 17-bp sequence motif was retarded by purified EraR, a LuxR-type transcription regulator that is transcribed divergently from exaA. EraR also showed a positive interaction with RpoN in two-hybrid and pulldown assays. IMPORTANCE Quinoprotein alcohol dehydrogenase (ExaA) plays an important role in the catabolism of alcohols in bacteria. Although exaA expression is thought to be regulated by a two-component system consisting of EraS and EraR, the mechanism of regulation was not known. This study shows the details of the regulation of expression of the exaA gene in A. brasilense. We have shown here that exaA of A. brasilense is maximally induced by glycerol and harbors a σ54-dependent promoter. The response regulator EraR binds to an inverted repeat located upstream of the exaA promoter. This study shows that a LuxR-type response regulator (EraR) binds upstream of the exaA gene and physically interacts with σ54. The unique feature of this regulation is that EraR is a LuxR-type transcription regulator that lacks the GAFTGA motif, a characteristic feature of the enhancer binding proteins that are known to

  15. Regulation of a Glycerol-Induced Quinoprotein Alcohol Dehydrogenase by σ54 and a LuxR-Type Regulator in Azospirillum brasilense Sp7.

    PubMed

    Singh, Vijay Shankar; Dubey, Ashutosh Prakash; Gupta, Ankush; Singh, Sudhir; Singh, Bhupendra Narain; Tripathi, Anil Kumar

    2017-07-01

    Azospirillum brasilense Sp7 uses glycerol as a carbon source for growth and nitrogen fixation. When grown in medium containing glycerol as a source of carbon, it upregulates the expression of a protein which was identified as quinoprotein alcohol dehydrogenase (ExaA). Inactivation of exaA adversely affects the growth of A. brasilense on glycerol. A determination of the transcription start site of exaA revealed an RpoN-dependent -12/-24 promoter consensus. The expression of an exaA :: lacZ fusion was induced maximally by glycerol and was dependent on σ 54 Bioinformatic analysis of the sequence flanking the -12/-24 promoter revealed a 17-bp sequence motif with a dyad symmetry of 6 nucleotides upstream of the promoter, the disruption of which caused a drastic reduction in promoter activity. The electrophoretic mobility of a DNA fragment containing the 17-bp sequence motif was retarded by purified EraR, a LuxR-type transcription regulator that is transcribed divergently from exaA EraR also showed a positive interaction with RpoN in two-hybrid and pulldown assays. IMPORTANCE Quinoprotein alcohol dehydrogenase (ExaA) plays an important role in the catabolism of alcohols in bacteria. Although exaA expression is thought to be regulated by a two-component system consisting of EraS and EraR, the mechanism of regulation was not known. This study shows the details of the regulation of expression of the exaA gene in A. brasilense We have shown here that exaA of A. brasilense is maximally induced by glycerol and harbors a σ 54 -dependent promoter. The response regulator EraR binds to an inverted repeat located upstream of the exaA promoter. This study shows that a LuxR-type response regulator (EraR) binds upstream of the exaA gene and physically interacts with σ 54 The unique feature of this regulation is that EraR is a LuxR-type transcription regulator that lacks the GAFTGA motif, a characteristic feature of the enhancer binding proteins that are known to interact with σ 54

  16. Annotation of Ehux ESTs

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kuo, Alan; Grigoriev, Igor

    2009-06-12

    22 percent ESTs do no align with scaffolds. EST Pipeleine assembles 17126 consensi from the noaligned ESTs. Annotation Pipeline predicts 8564 ORFS on the consensi. Domain analysis of ORFs reveals missing genes. Cluster analysis reveals missing genes. Expression analysis reveals potential strain specific genes.

  17. ApiEST-DB: analyzing clustered EST data of the apicomplexan parasites.

    PubMed

    Li, Li; Crabtree, Jonathan; Fischer, Steve; Pinney, Deborah; Stoeckert, Christian J; Sibley, L David; Roos, David S

    2004-01-01

    ApiEST-DB (http://www.cbil.upenn.edu/paradbs-servlet/) provides integrated access to publicly available EST data from protozoan parasites in the phylum Apicomplexa. The database currently incorporates a total of nearly 100,000 ESTs from several parasite species of clinical and/or veterinary interest, including Eimeria tenella, Neospora caninum, Plasmodium falciparum, Sarcocystis neurona and Toxoplasma gondii. To facilitate analysis of these data, EST sequences were clustered and assembled to form consensus sequences for each organism, and these assemblies were then subjected to automated annotation via similarity searches against protein and domain databases. The underlying relational database infrastructure, Genomics Unified Schema (GUS), enables complex biologically based queries, facilitating validation of gene models, identification of alternative splicing, detection of single nucleotide polymorphisms, identification of stage-specific genes and recognition of phylogenetically conserved and phylogenetically restricted sequences.

  18. LuxGLM: a probabilistic covariate model for quantification of DNA methylation modifications with complex experimental designs

    PubMed Central

    Äijö, Tarmo; Yue, Xiaojing; Rao, Anjana; Lähdesmäki, Harri

    2016-01-01

    Motivation: 5-methylcytosine (5mC) is a widely studied epigenetic modification of DNA. The ten-eleven translocation (TET) dioxygenases oxidize 5mC into oxidized methylcytosines (oxi-mCs): 5-hydroxymethylcytosine (5hmC), 5-formylcytosine (5fC) and 5-carboxylcytosine (5caC). DNA methylation modifications have multiple functions. For example, 5mC is shown to be associated with diseases and oxi-mC species are reported to have a role in active DNA demethylation through 5mC oxidation and DNA repair, among others, but the detailed mechanisms are poorly understood. Bisulphite sequencing and its various derivatives can be used to gain information about all methylation modifications at single nucleotide resolution. Analysis of bisulphite based sequencing data is complicated due to the convoluted read-outs and experiment-specific variation in biochemistry. Moreover, statistical analysis is often complicated by various confounding effects. How to analyse 5mC and oxi-mC data sets with arbitrary and complex experimental designs is an open and important problem. Results: We propose the first method to quantify oxi-mC species with arbitrary covariate structures from bisulphite based sequencing data. Our probabilistic modeling framework combines a previously proposed hierarchical generative model for oxi-mC-seq data and a general linear model component to account for confounding effects. We show that our method provides accurate methylation level estimates and accurate detection of differential methylation when compared with existing methods. Analysis of novel and published data gave insights into to the demethylation of the forkhead box P3 (Foxp3) locus during the induced T regulatory cell differentiation. We also demonstrate how our covariate model accurately predicts methylation levels of the Foxp3 locus. Collectively, LuxGLM method improves the analysis of DNA methylation modifications, particularly for oxi-mC species. Availability and Implementation: An implementation of the

  19. The Safety and Efficacy of the 1540nm Non-Ablative Fractional XD Probe of Star Lux 500 Device in the Treatment of Striae Alba: Before-After Study.

    PubMed

    Malekzad, Farhad; Shakoei, Safoura; Ayatollahi, Azin; Hejazi, Somayeh

    2014-01-01

    Striae distensae (SD) are a frequent skin condition for which treatment remains a challenge. The 1540-nm non-ablative fractional laser (Star Lux 500) has been shown to improve atrophic scars by increasing the amount of dermal collagen. To assess the safety and efficacy of the Star Lux 500 laser in the treatment of mature hypopigmented striae in Persian people (Striae Alba). Ten women aged 26-50 years with SD and Fitzpatrick skin types III-V were enrolled in the study. The exclusion criteria were a history of keloids, photosensitivity and collagen, elastin disorders as well as history of other striae treatment within one year. The lesions were treated with non-ablative fractional laser 1540nm, and a total of four treatments were given at 4-week intervals. Clinical standard photographs were taken before each treatment. Also, patients were followed up at 3 months after the last treatment. Clinical improvement was assessed by comparing baseline and post-treatment photographs by two independent blinded physicians using grading scale. Treatment efficacy analysis was performed via the comparison between the images taken before and after each treatment session. There was a clinically appreciable improvement in striae ranging from 1 to 24%. A significant improvement in striae between the 16-week treatment and the 4-week treatment was identified (P<0.0001). Three months after the final treatment, patients showed noticeable improvement in the striae, compared with baseline (P<0.048). Mild post inflammatory hyperpigmentation was observed in one patient after the 8-week treatment and mild to moderate acne occurred in another patient after 4 weeks of treatment. Therapy with Star lux 500 laser had clinically and statistically striae improvement with no adverse events. This may be a safe and an effective treatment modality for Striae Alba lesions.

  20. Calibration, event reconstruction, data analysis and limits calculation for the LUX dark matter experiment

    DOE PAGES

    Akerib, DS; Alsum, S; Araújo, HM; ...

    2018-01-05

    The LUX experiment has performed searches for dark matter particles scattering elastically on xenon nuclei, leading to stringent upper limits on the nuclear scattering cross sections for dark matter. Here, for results derived frommore » $${1.4}\\times 10^{4}\\;\\mathrm{kg\\,days}$$ of target exposure in 2013, details of the calibration, event-reconstruction, modeling, and statistical tests that underlie the results are presented. Detector performance is characterized, including measured efficiencies, stability of response, position resolution, and discrimination between electron- and nuclear-recoil populations. Models are developed for the drift field, optical properties, background populations, the electron- and nuclear-recoil responses, and the absolute rate of low-energy background events. Innovations in the analysis include in situ measurement of the photomultipliers' response to xenon scintillation photons, verification of fiducial mass with a low-energy internal calibration source, and new empirical models for low-energy signal yield based on large-sample, in situ calibrations.« less

  1. Calibration, event reconstruction, data analysis, and limit calculation for the LUX dark matter experiment

    DOE PAGES

    Akerib, D. S.; Alsum, S.; Araújo, H. M.; ...

    2018-05-31

    Here, the LUX experiment has performed searches for dark matter particles scattering elastically on xenon nuclei, leading to stringent upper limits on the nuclear scattering cross sections for dark matter. Here, for results derived frommore » $${1.4}\\times 10^{4}\\;\\mathrm{kg\\,days}$$ of target exposure in 2013, details of the calibration, event-reconstruction, modeling, and statistical tests that underlie the results are presented. Detector performance is characterized, including measured efficiencies, stability of response, position resolution, and discrimination between electron- and nuclear-recoil populations. Models are developed for the drift field, optical properties, background populations, the electron- and nuclear-recoil responses, and the absolute rate of low-energy background events. Innovations in the analysis include in situ measurement of the photomultipliers' response to xenon scintillation photons, verification of fiducial mass with a low-energy internal calibration source, and new empirical models for low-energy signal yield based on large-sample, in situ calibrations.« less

  2. Calibration, event reconstruction, data analysis, and limit calculation for the LUX dark matter experiment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Akerib, D. S.; Alsum, S.; Araújo, H. M.

    Here, the LUX experiment has performed searches for dark matter particles scattering elastically on xenon nuclei, leading to stringent upper limits on the nuclear scattering cross sections for dark matter. Here, for results derived frommore » $${1.4}\\times 10^{4}\\;\\mathrm{kg\\,days}$$ of target exposure in 2013, details of the calibration, event-reconstruction, modeling, and statistical tests that underlie the results are presented. Detector performance is characterized, including measured efficiencies, stability of response, position resolution, and discrimination between electron- and nuclear-recoil populations. Models are developed for the drift field, optical properties, background populations, the electron- and nuclear-recoil responses, and the absolute rate of low-energy background events. Innovations in the analysis include in situ measurement of the photomultipliers' response to xenon scintillation photons, verification of fiducial mass with a low-energy internal calibration source, and new empirical models for low-energy signal yield based on large-sample, in situ calibrations.« less

  3. The effect of altered gravity on immune cells (Ground studies: TRIPLE LUX-A BIOLAB experiment)

    NASA Astrophysics Data System (ADS)

    Horn, Astrid; Huber, Kathrin; Kuebler, Ulrich; Briganti, Luca; Baerwalde, Sven; Zander, Vanja; Ullrich, Oliver; Hemmersbach, Ruth

    The experiment TRIPLE LUX A, whose performance on Biolab is foreseen for 2010, aims to increase the information about the functioning of immune cells during space flight. Thus, we investigate the impact of altered gravity -microgravity and hypergravity conditions -on the immune response of mammalian macrophages. Previous studies had already demonstrated that phagocytosis in macrophages, an essential step in the innate immune response, is decreased on a fast rotating clinostat. Now, the production of ROS (reactive oxygen species) within the oxidative burst reaction, was measured by means of a luminol assay (luminescence + photo-multiplier technique) comparable to the set up which will be used in the TRIPLE LUX flight hardware. The kinetics of the ROS production was investigated a) under 1 g conditions, b) on a clinostat (with one rotation axis) under varied rotational speed c) in short-term real micro-gravity on a parabolic flight and d) in hypergravity (1.8 g) on the Short Arm Human Centrifuge (SAHC) at DLR Cologne. By means of a photomultiplier clinostat online kinetic luminescent measurements during clinorotation were possible. Permanent fast clinorotation (60 rpm) leads to a dramatic reduction of the oxidative burst signal by up to 60% compared to the signal at 1 g. Slower rotation (30 rpm to 2 rpm) reduces the signal strength even more by up to 90% of the original strength. 60 rpm clinorotation as well as short-term real microgravity (22 s) during parabolic flight likewise decreases the signal of the oxidative burst to a comparable amount, thus the term "simulated weightlessness" is valid for the chosen experimental condi-tion. In contrast, hypergravity leads to a significant signal increase. The results demonstrate a clear effect of altered gravity on the immune response of the macrophages. In the upcoming ISS experiment the established test system (oxidative burst of macrophages) will be tested in continues microgravity within the Biolab hardware, designed by

  4. A tour of forest nurseries in the Pacific Islands of Micronesia and American Samoa

    Treesearch

    Leonard A. Newell

    2002-01-01

    Forestry programs in the American-affiliated islands of Micronesia and American Samoa are relatively young, compared to those of mainland states. American Samoa and Guam have been American Flag Territories since 1899, but neither had a forestry program before 1970. American Samoa had no forestry program until 1987. After World War II, the United States was the de facta...

  5. Luminescent properties of Tm3-xLuxAl5O12:Ce single crystalline films

    NASA Astrophysics Data System (ADS)

    Zorenko, Yu.; Gorbenko, V.; Zorenko, T.; Suchocki, A.; Zhydachevskyy, Ya.; Fabisiak, K.; Paprocki, K.; Bilski, P.; Twardak, A.; Fedorov, A.

    2017-07-01

    The work devoted to the investigation of a new luminescent and scintillation material based on the single crystalline films (SCFs) of Tm3-xLuxAG:Ce garnet; x = 0-1.5, grown by LPE method from PbO based flux. The best scintillation properties are achieved for SCFs of Tm1.5Lu1.5Al5O12:Ce composition. We have found that direct Tm → Ce and backside Ce → Tm energy transfer processes are observed in Tm1.5Lu1.5Al5O12:Ce. Due to elimination of traps in the 300-450 °C range, the relatively fast scintillation decay is realized in highly doped Tm1.5Lu1.5Al5O12:Ce SCFs. For this reason, Tm doping can be considered as a suitable way for improvement of the scintillation efficiency in other Ce3+ doped garnet compounds.

  6. A study of Lux-Flood acid-base reactions in KBr melts at 800°C

    NASA Astrophysics Data System (ADS)

    Rebrova, T. P.; Cherginets, V. L.; Ponomarenko, T. V.

    2009-11-01

    The dissociation of CO{3/2-} (p K = 2.4 ± 0.2) and precipitation of MgO (p L MgO = 10.66 ± 0.1) in a KBr melt at 800°C were studied potentiometrically with the use of a Pt(O2)|ZrO2|(Y2O3) membrane oxygen electrode. The direct calibration of the electrochemical circuit allowed only the equilibrium concentration of O2- (of strong bases) to be determined in the melt. The total concentration of oxygen-containing impurities, including CO{3/2-} and CO{4/2-} weak bases, can be found by the potentiometric titration of a sample of KBr by adding MgCl2 (Mg2+), a strong Lux-Flood acid, which causes the decomposition of these oxygen-containing anions. This reaction can also be used to remove oxo anions from alkali metal halide melts.

  7. Projected WIMP Sensitivity of the LUX-ZEPLIN (LZ) Dark Matter Experiment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Akerib, D.S.; et al.

    LUX-ZEPLIN (LZ) is a next generation dark matter direct detection experiment that will operate 4850 feet underground at the Sanford Underground Research Facility (SURF) in Lead, South Dakota, USA. Using a two-phase xenon detector with an active mass of 7 tonnes, LZ will search primarily for low-energy interactions with Weakly Interacting Massive Particles (WIMPs), which are hypothesized to make up the dark matter in our galactic halo. In this paper, the projected WIMP sensitivity of LZ is presented based on the latest background estimates and simulations of the detector. For a 1000 live day run using a 5.6 tonne fiducial mass, LZ is projected to exclude at 90% confidence level spin-independent WIMP-nucleon cross sections abovemore » $$1.6 \\times 10^{-48}$$ cm$$^{2}$$ for a 40 $$\\mathrm{GeV}/c^{2}$$ mass WIMP. Additionally, a $$5\\sigma$$ discovery potential is projected reaching cross sections below the existing and projected exclusion limits of similar experiments that are currently operating. For spin-dependent WIMP-neutron(-proton) scattering, a sensitivity of $$2.7 \\times 10^{-43}$$ cm$$^{2}$$ ($$8.1 \\times 10^{-42}$$ cm$$^{2}$$) for a 40 $$\\mathrm{GeV}/c^{2}$$ mass WIMP is expected. With construction well underway, LZ is on track for underground installation at SURF in 2019 and will start collecting data in 2020.« less

  8. Expression of lux-genes as an indicator of metabolic activity of cells in model ecosystem studies

    NASA Astrophysics Data System (ADS)

    Boyandin, A. N.; Popova, L. Yu.

    Quick response to different impacts and easy measurement make the luminescent systems of luminous bacteria an object convenient for application in various fields. Cloning of gene luminescence in different organisms is currently used to study both the survival of microbial cells and the effect of different factors on their metabolic activity, including the environment. A primary test-object in estimating bacteriological contamination of water bodies, Escherichia coli, can be conveniently used as an indicator of bactericidal properties of aquatic ecosystems. The application of Escherichia coli Z905/pPHL7 (lux +) as a marker microorganism can facilitate monitoring the microbiological status of closed biocenoses, including systems with higher organisms. The investigation of various parameters of microecosystems (carbon nutrition type, concentrations of inorganic ions and toxic compounds) shows that the recombinant strain E. coli Z905/pPHL7 can be effectively used as a marker.

  9. Conserved tyrosine 182 residue in hyperthermophilic esterase EstE1 plays a critical role in stabilizing the active site.

    PubMed

    Truongvan, Ngoc; Chung, Hye-Shin; Jang, Sei-Heon; Lee, ChangWoo

    2016-03-01

    An aromatic amino acid, Tyr or Trp, located in the esterase active site wall, is highly conserved, with hyperthermophilic esterases showing preference for Tyr and lower temperature esterases showing preference for Trp. In this study, we investigated the role of Tyr(182) in the active site wall of hyperthermophilic esterase EstE1. Mutation of Tyr to Phe or Ala had a moderate effect on EstE1 thermal stability. However, a small-to-large mutation such as Tyr to His or Trp had a devastating effect on thermal stability. All mutant EstE1 enzymes showed reduced catalytic rates and enhanced substrate affinities as compared with wild-type EstE1. Hydrogen bond formation involving Tyr(182) was unimportant for maintaining EstE1 thermal stability, as the EstE1 structure is already adapted to high temperatures via increased intramolecular interactions. However, removal of hydrogen bond from Tyr(182) significantly decreased EstE1 catalytic activity, suggesting its role in stabilization of the active site. These results suggest that Tyr is preferred over a similarly sized Phe residue or bulky His or Trp residue in the active site walls of hyperthermophilic esterases for stabilizing the active site and regulating catalytic activity at high temperatures.

  10. Characterization of EST-derived and non-EST simple sequence repeats in an F₁ hybrid population of Vitis vinifera L.

    PubMed

    Kayesh, E; Bilkish, N; Liu, G S; Chen, W; Leng, X P; Fang, J G

    2014-03-31

    Among different classes of molecular markers, expressed sequence tags (ESTs) are a new resource for developing simple sequence repeat (SSR) functional markers for genotyping and genetic mapping in F1 hybrid populations of Vitis vinifera L. Recently, because of the availability of an enormous amount of data for ESTs in the public domain, the emphasis has shifted from genomic SSRs to EST-SSRs, which belong to transcribed regions of the genome and may have a role in gene expression or function. The objective of this study was to assess the polymorphisms among 94 F1 hybrids from "Early Rose" and "Red Globe" using 25 EST-derived and 25 non-EST SSR markers. A total collection of 362,375 grape ESTs that were retrieved from the National Center for Biotechnology Information (NCBI) and 2522 EST-SSR sequences were identified. From them, 205 primer pairs were randomly selected, including 176 pairs that were EST-derived and 29 non-EST SSR primer pairs, for polymerase chain reaction amplification. A total of 131 alleles were amplified using 50 pairs of primers; 78 alleles were amplified using EST-derived SSR primers and 53 were from non-EST SSR primers. At most, 6 and 5 alleles were amplified by EST-derived and non-EST SSR primers, respectively. The EST-derived SSR markers showed a maximum polymorphic information content (PIC) value of 1 and a minimum of 0.33 while non-EST SSR markers had maximum and minimum PIC values of 1 and 0.25, respectively. The average PIC value was 0.56 for EST-derived SSR markers and 0.45 for non-EST SSR markers.

  11. Army Logistician. Volume 37, Issue 3, May-June 2005

    DTIC Science & Technology

    2005-06-01

    tics Civil Augmentation Program (LOGCAP) did not meet their expectations. I believe the commanders’ perceptions stemmed, in part, from the fact...a monetary ceiling ; however, the number of events or contingencies KBR can support is limited. The chart above shows some of the services LOG- CAP...landing craft or amphibious tractors. In cooperation with the Lebanese Army, marines kept the airport open for commercial air traffic. The following

  12. NMR shielding and spin–rotation constants of {sup 175}LuX (X = {sup 19}F, {sup 35}Cl, {sup 79}Br, {sup 127}I) molecules

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Demissie, Taye B.

    2015-12-31

    This presentation demonstrates the relativistic effects on the spin-rotation constants, absolute nuclear magnetic resonance (NMR) shielding constants and shielding spans of {sup 175}LuX (X = {sup 19}F, {sup 35}Cl, {sup 79}Br, {sup 127}I) molecules. The results are obtained from calculations performed using density functional theory (non-relativistic and four-component relativistic) and coupled-cluster calculations. The spin-rotation constants are compared with available experimental values. In most of the molecules studied, relativistic effects make an order of magnitude difference on the NMR absolute shielding constants.

  13. Promoter Engineering Reveals the Importance of Heptameric Direct Repeats for DNA Binding by Streptomyces Antibiotic Regulatory Protein-Large ATP-Binding Regulator of the LuxR Family (SARP-LAL) Regulators in Streptomyces natalensis.

    PubMed

    Barreales, Eva G; Vicente, Cláudia M; de Pedro, Antonio; Santos-Aberturas, Javier; Aparicio, Jesús F

    2018-05-15

    The biosynthesis of small-size polyene macrolides is ultimately controlled by a couple of transcriptional regulators that act in a hierarchical way. A Streptomyces antibiotic regulatory protein-large ATP-binding regulator of the LuxR family (SARP-LAL) regulator binds the promoter of a PAS-LuxR regulator-encoding gene and activates its transcription, and in turn, the gene product of the latter activates transcription from various promoters of the polyene gene cluster directly. The primary operator of PimR, the archetype of SARP-LAL regulators, contains three heptameric direct repeats separated by four-nucleotide spacers, but the regulator can also bind a secondary operator with only two direct repeats separated by a 3-nucleotide spacer, both located in the promoter region of its unique target gene, pimM A similar arrangement of operators has been identified for PimR counterparts encoded by gene clusters for different antifungal secondary metabolites, including not only polyene macrolides but peptidyl nucleosides, phoslactomycins, or cycloheximide. Here, we used promoter engineering and quantitative transcriptional analyses to determine the contributions of the different heptameric repeats to transcriptional activation and final polyene production. Optimized promoters have thus been developed. Deletion studies and electrophoretic mobility assays were used for the definition of DNA-binding boxes formed by 22-nucleotide sequences comprising two conserved heptameric direct repeats separated by four-nucleotide less conserved spacers. The cooperative binding of PimR SARP appears to be the mechanism involved in the binding of regulator monomers to operators, and at least two protein monomers are required for efficient binding. IMPORTANCE Here, we have shown that a modulation of the production of the antifungal pimaricin in Streptomyces natalensis can be accomplished via promoter engineering of the PAS-LuxR transcriptional activator pimM The expression of this gene is

  14. The Human EST Ontology Explorer: a tissue-oriented visualization system for ontologies distribution in human EST collections.

    PubMed

    Merelli, Ivan; Caprera, Andrea; Stella, Alessandra; Del Corvo, Marcello; Milanesi, Luciano; Lazzari, Barbara

    2009-10-15

    The NCBI dbEST currently contains more than eight million human Expressed Sequenced Tags (ESTs). This wide collection represents an important source of information for gene expression studies, provided it can be inspected according to biologically relevant criteria. EST data can be browsed using different dedicated web resources, which allow to investigate library specific gene expression levels and to make comparisons among libraries, highlighting significant differences in gene expression. Nonetheless, no tool is available to examine distributions of quantitative EST collections in Gene Ontology (GO) categories, nor to retrieve information concerning library-dependent EST involvement in metabolic pathways. In this work we present the Human EST Ontology Explorer (HEOE) http://www.itb.cnr.it/ptp/human_est_explorer, a web facility for comparison of expression levels among libraries from several healthy and diseased tissues. The HEOE provides library-dependent statistics on the distribution of sequences in the GO Direct Acyclic Graph (DAG) that can be browsed at each GO hierarchical level. The tool is based on large-scale BLAST annotation of EST sequences. Due to the huge number of input sequences, this BLAST analysis was performed with the aid of grid computing technology, which is particularly suitable to address data parallel task. Relying on the achieved annotation, library-specific distributions of ESTs in the GO Graph were inferred. A pathway-based search interface was also implemented, for a quick evaluation of the representation of libraries in metabolic pathways. EST processing steps were integrated in a semi-automatic procedure that relies on Perl scripts and stores results in a MySQL database. A PHP-based web interface offers the possibility to simultaneously visualize, retrieve and compare data from the different libraries. Statistically significant differences in GO categories among user selected libraries can also be computed. The HEOE provides an

  15. Biosynthesis of the antimicrobial cyclic lipopeptides nunamycin and nunapeptin by Pseudomonas fluorescens strain In5 is regulated by the LuxR-type transcriptional regulator NunF.

    PubMed

    Hennessy, Rosanna C; Phippen, Christopher B W; Nielsen, Kristian F; Olsson, Stefan; Stougaard, Peter

    2017-12-01

    Nunamycin and nunapeptin are two antimicrobial cyclic lipopeptides (CLPs) produced by Pseudomonas fluorescens In5 and synthesized by nonribosomal synthetases (NRPS) located on two gene clusters designated the nun-nup regulon. Organization of the regulon is similar to clusters found in other CLP-producing pseudomonads except for the border regions where putative LuxR-type regulators are located. This study focuses on understanding the regulatory role of the LuxR-type-encoding gene nunF in CLP production of P. fluorescens In5. Functional analysis of nunF coupled with liquid chromatography-high-resolution mass spectrometry (LC-HRMS) showed that CLP biosynthesis is regulated by nunF. Quantitative real-time PCR analysis indicated that transcription of the NRPS genes catalyzing CLP production is strongly reduced when nunF is mutated indicating that nunF is part of the nun-nup regulon. Swarming and biofilm formation was reduced in a nunF knockout mutant suggesting that these CLPs may also play a role in these phenomena as observed in other pseudomonads. Fusion of the nunF promoter region to mCherry showed that nunF is strongly upregulated in response to carbon sources indicating the presence of a fungus suggesting that environmental elicitors may also influence nunF expression which upon activation regulates nunamycin and nunapeptin production required for the growth inhibition of phytopathogens. © 2017 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

  16. Closing in on singlet scalar dark matter: LUX, invisible Higgs decays and gamma-ray lines

    DOE PAGES

    Feng, Lei; Profumo, Stefano; Ubaldi, Lorenzo

    2015-03-10

    Here, we study the implications of the Higgs discovery and of recent results from dark matter searches on real singlet scalar dark matter. The phenomenology of the model is defined by only two parameters, the singlet scalar mass m S and the quartic coupling a 2 between the SU(2) Higgs and the singlet scalar. We concentrate on the window 5 < m S /GeV < 300. The most dramatic impact on the viable parameter space of the model comes from direct dark matter searches with LUX, and, for very low masses in the few GeV range, from constraints from themore » invisible decay width of the Higgs. In the resonant region the best constraints come from gamma-ray line searches. We show that they leave only a small region of viable parameter space, for dark matter masses within a few percent of half the mass of the Higgs. We demonstrate that direct and indirect dark matter searches (especially the search for monochromatic gamma-ray lines) will play a key role in closing the residual parameter space in the near future.« less

  17. Orbital Monitoring of the AstraLux Large M-dwarf Multiplicity Sample

    NASA Astrophysics Data System (ADS)

    Janson, Markus; Bergfors, Carolina; Brandner, Wolfgang; Bonnefoy, Mickaël; Schlieder, Joshua; Köhler, Rainer; Hormuth, Felix; Henning, Thomas; Hippler, Stefan

    2014-10-01

    Orbital monitoring of M-type binaries is essential for constraining their fundamental properties. This is particularly useful in young systems, where the extended pre-main-sequence evolution can allow for precise isochronal dating. Here, we present the continued astrometric monitoring of the more than 200 binaries of the AstraLux Large Multiplicity Survey, building both on our previous work, archival data, and new astrometric data spanning the range of 2010-2012. The sample is very young overall—all included stars have known X-ray emission, and a significant fraction (18%) of them have recently also been identified as members of young moving groups in the solar neighborhood. We identify ~30 targets that both have indications of being young and for which an orbit either has been closed or appears possible to close in a reasonable time frame (a few years to a few decades). One of these cases, GJ 4326, is, however, identified as probably being substantially older than has been implied from its apparent moving group membership, based on astrometric and isochronal arguments. With further astrometric monitoring, these targets will provide a set of empirical isochrones, against which theoretical isochrones can be calibrated, and which can be used to evaluate the precise ages of nearby young moving groups. Based on observations collected at the European Southern Observatory, Chile, under observing programs 081.C-0314(A), 082.C-0053(A), and 084.C-0812(A), and on observations collected at the Centro Astronómico Hispano Alemán (CAHA) at Calar Alto, operated jointly by the Max-Planck Institute for Astronomy and the Instituto de Astrofísica de Andalucía (CSIC).

  18. ESTs and EST-linked polymorphisms for genetic mapping and phylogenetic reconstruction in the guppy, Poecilia reticulata

    PubMed Central

    Dreyer, Christine; Hoffmann, Margarete; Lanz, Christa; Willing, Eva-Maria; Riester, Markus; Warthmann, Norman; Sprecher, Andrea; Tripathi, Namita; Henz, Stefan R; Weigel, Detlef

    2007-01-01

    Background The guppy, Poecilia reticulata, is a well-known model organism for studying inheritance and variation of male ornamental traits as well as adaptation to different river habitats. However, genomic resources for studying this important model were not previously widely available. Results With the aim of generating molecular markers for genetic mapping of the guppy, cDNA libraries were constructed from embryos and different adult organs to generate expressed sequence tags (ESTs). About 18,000 ESTs were annotated according to BLASTN and BLASTX results and the sequence information from the 3' UTRs was exploited to generate PCR primers for re-sequencing of genomic DNA from different wild type strains. By comparison of EST-linked genomic sequences from at least four different ecotypes, about 1,700 polymorphisms were identified, representing about 400 distinct genes. Two interconnected MySQL databases were built to organize the ESTs and markers, respectively. A robust phylogeny of the guppy was reconstructed, based on 10 different nuclear genes. Conclusion Our EST and marker databases provide useful tools for genetic mapping and phylogenetic studies of the guppy. PMID:17686157

  19. EST! best practices

    DOT National Transportation Integrated Search

    2000-10-05

    This booklet presents the eighteen winners in a competition for projects that promote environmentally sustainable transportation (EST). These range from car sharing to hydrogen fueled buses to public transit promotion campaign. Each project is presen...

  20. PAVE: program for assembling and viewing ESTs.

    PubMed

    Soderlund, Carol; Johnson, Eric; Bomhoff, Matthew; Descour, Anne

    2009-08-26

    New sequencing technologies are rapidly emerging. Many laboratories are simultaneously working with the traditional Sanger ESTs and experimenting with ESTs generated by the 454 Life Science sequencers. Though Sanger ESTs have been used to generate contigs for many years, no program takes full advantage of the 5' and 3' mate-pair information, hence, many tentative transcripts are assembled into two separate contigs. The new 454 technology has the benefit of high-throughput expression profiling, but introduces time and space problems for assembling large contigs. The PAVE (Program for Assembling and Viewing ESTs) assembler takes advantage of the 5' and 3' mate-pair information by requiring that the mate-pairs be assembled into the same contig and joined by n's if the two sub-contigs do not overlap. It handles the depth of 454 data sets by "burying" similar ESTs during assembly, which retains the expression level information while circumventing time and space problems. PAVE uses MegaBLAST for the clustering step and CAP3 for assembly, however it assembles incrementally to enforce the mate-pair constraint, bury ESTs, and reduce incorrect joins and splits. The PAVE data management system uses a MySQL database to store multiple libraries of ESTs along with their metadata; the management system allows multiple assemblies with variations on libraries and parameters. Analysis routines provide standard annotation for the contigs including a measure of differentially expressed genes across the libraries. A Java viewer program is provided for display and analysis of the results. Our results clearly show the benefit of using the PAVE assembler to explicitly use mate-pair information and bury ESTs for large contigs. The PAVE assembler provides a software package for assembling Sanger and/or 454 ESTs. The assembly software, data management software, Java viewer and user's guide are freely available.

  1. JPRS Report, Science & Technology, China.

    DTIC Science & Technology

    1992-11-18

    LPS O-Antigen Genes in E. coli HB101 40091002L Beijing YICHUAN XUEBAO fACTA GENETICA SINICA] in Chinese Vol 19 No 4, Aug 92 pp 378-384 [English...Isolation of Vitamine B2 Auxotroph and Preliminary Genetic Mapping in Salmonella typhimurium 40091002J Beijing YICHUAN XUEBAO [ACTA GENETICA SINICA] in...YICHUAN XUEBAO [ACTA GENETICA SINICA] in Chinese Vol 19 No 4, Aug 92 pp 369-377 [English abstract of article by Hai Weili [3189 0251 0500] and

  2. Engineering of Bacteriophages Y2::dpoL1-C and Y2::luxAB for Efficient Control and Rapid Detection of the Fire Blight Pathogen, Erwinia amylovora.

    PubMed

    Born, Yannick; Fieseler, Lars; Thöny, Valentin; Leimer, Nadja; Duffy, Brion; Loessner, Martin J

    2017-06-15

    Erwinia amylovora is the causative agent of fire blight, a devastating plant disease affecting members of the Rosaceae Alternatives to antibiotics for control of fire blight symptoms and outbreaks are highly desirable, due to increasing drug resistance and tight regulatory restrictions. Moreover, the available diagnostic methods either lack sensitivity, lack speed, or are unable to discriminate between live and dead bacteria. Owing to their extreme biological specificity, bacteriophages are promising alternatives for both aims. In this study, the virulent broad-host-range E. amylovora virus Y2 was engineered to enhance its killing activity and for use as a luciferase reporter phage, respectively. Toward these aims, a depolymerase gene of E. amylovora virus L1 ( dpoL1-C ) or a bacterial luxAB fusion was introduced into the genome of Y2 by homologous recombination. The genes were placed downstream of the major capsid protein orf68 , under the control of the native promoter. The modifications did not affect viability of infectivity of the recombinant viruses. Phage Y2:: dpoL1-C demonstrated synergistic activity between the depolymerase degrading the exopolysaccharide capsule and phage infection, which greatly enhanced bacterial killing. It also significantly reduced the ability of E. amylovora to colonize the surface of detached flowers. The reporter phage Y2:: luxAB transduced bacterial luciferase into host cells and induced synthesis of large amounts of a LuxAB luciferase fusion. After the addition of aldehyde substrate, bioluminescence could be readily monitored, and this enabled rapid and specific detection of low numbers of viable bacteria, without enrichment, both in vitro and in plant material. IMPORTANCE Fire blight, caused by Erwinia amylovora , is the major threat to global pome fruit production, with high economic losses every year. Bacteriophages represent promising alternatives to not only control the disease, but also for rapid diagnostics. To enhance

  3. Engineering of Bacteriophages Y2::dpoL1-C and Y2::luxAB for Efficient Control and Rapid Detection of the Fire Blight Pathogen, Erwinia amylovora

    PubMed Central

    Born, Yannick; Fieseler, Lars; Thöny, Valentin; Leimer, Nadja; Duffy, Brion

    2017-01-01

    ABSTRACT Erwinia amylovora is the causative agent of fire blight, a devastating plant disease affecting members of the Rosaceae. Alternatives to antibiotics for control of fire blight symptoms and outbreaks are highly desirable, due to increasing drug resistance and tight regulatory restrictions. Moreover, the available diagnostic methods either lack sensitivity, lack speed, or are unable to discriminate between live and dead bacteria. Owing to their extreme biological specificity, bacteriophages are promising alternatives for both aims. In this study, the virulent broad-host-range E. amylovora virus Y2 was engineered to enhance its killing activity and for use as a luciferase reporter phage, respectively. Toward these aims, a depolymerase gene of E. amylovora virus L1 (dpoL1-C) or a bacterial luxAB fusion was introduced into the genome of Y2 by homologous recombination. The genes were placed downstream of the major capsid protein orf68, under the control of the native promoter. The modifications did not affect viability of infectivity of the recombinant viruses. Phage Y2::dpoL1-C demonstrated synergistic activity between the depolymerase degrading the exopolysaccharide capsule and phage infection, which greatly enhanced bacterial killing. It also significantly reduced the ability of E. amylovora to colonize the surface of detached flowers. The reporter phage Y2::luxAB transduced bacterial luciferase into host cells and induced synthesis of large amounts of a LuxAB luciferase fusion. After the addition of aldehyde substrate, bioluminescence could be readily monitored, and this enabled rapid and specific detection of low numbers of viable bacteria, without enrichment, both in vitro and in plant material. IMPORTANCE Fire blight, caused by Erwinia amylovora, is the major threat to global pome fruit production, with high economic losses every year. Bacteriophages represent promising alternatives to not only control the disease, but also for rapid diagnostics. To

  4. EST Express: PHP/MySQL based automated annotation of ESTs from expression libraries.

    PubMed

    Smith, Robin P; Buchser, William J; Lemmon, Marcus B; Pardinas, Jose R; Bixby, John L; Lemmon, Vance P

    2008-04-10

    Several biological techniques result in the acquisition of functional sets of cDNAs that must be sequenced and analyzed. The emergence of redundant databases such as UniGene and centralized annotation engines such as Entrez Gene has allowed the development of software that can analyze a great number of sequences in a matter of seconds. We have developed "EST Express", a suite of analytical tools that identify and annotate ESTs originating from specific mRNA populations. The software consists of a user-friendly GUI powered by PHP and MySQL that allows for online collaboration between researchers and continuity with UniGene, Entrez Gene and RefSeq. Two key features of the software include a novel, simplified Entrez Gene parser and tools to manage cDNA library sequencing projects. We have tested the software on a large data set (2,016 samples) produced by subtractive hybridization. EST Express is an open-source, cross-platform web server application that imports sequences from cDNA libraries, such as those generated through subtractive hybridization or yeast two-hybrid screens. It then provides several layers of annotation based on Entrez Gene and RefSeq to allow the user to highlight useful genes and manage cDNA library projects.

  5. EST Express: PHP/MySQL based automated annotation of ESTs from expression libraries

    PubMed Central

    Smith, Robin P; Buchser, William J; Lemmon, Marcus B; Pardinas, Jose R; Bixby, John L; Lemmon, Vance P

    2008-01-01

    Background Several biological techniques result in the acquisition of functional sets of cDNAs that must be sequenced and analyzed. The emergence of redundant databases such as UniGene and centralized annotation engines such as Entrez Gene has allowed the development of software that can analyze a great number of sequences in a matter of seconds. Results We have developed "EST Express", a suite of analytical tools that identify and annotate ESTs originating from specific mRNA populations. The software consists of a user-friendly GUI powered by PHP and MySQL that allows for online collaboration between researchers and continuity with UniGene, Entrez Gene and RefSeq. Two key features of the software include a novel, simplified Entrez Gene parser and tools to manage cDNA library sequencing projects. We have tested the software on a large data set (2,016 samples) produced by subtractive hybridization. Conclusion EST Express is an open-source, cross-platform web server application that imports sequences from cDNA libraries, such as those generated through subtractive hybridization or yeast two-hybrid screens. It then provides several layers of annotation based on Entrez Gene and RefSeq to allow the user to highlight useful genes and manage cDNA library projects. PMID:18402700

  6. Identification of true EST alignments for recognising transcribed regions.

    PubMed

    Ma, Chuang; Wang, Jia; Li, Lun; Duan, Mo-Jie; Zhou, Yan-Hong

    2011-01-01

    Transcribed regions can be determined by aligning Expressed Sequence Tags (ESTs) with genome sequences. The kernel of this strategy is to effectively distinguish true EST alignments from spurious ones. In this study, three measures including Direction Check, Identity Check and Terminal Check were introduced to more effectively eliminate spurious EST alignments. On the basis of these introduced measures and other widely used measures, a computational tool, named ESTCleanser, has been developed to identify true EST alignments for obtaining reliable transcribed regions. The performance of ESTCleanser has been evaluated on the well-annotated human ENCyclopedia of DNA Elements (ENCODE) regions using human ESTs in the dbEST database. The evaluation results show that the accuracy of ESTCleanser at exon and intron levels is more remarkably enhanced than that of UCSC-spliced EST alignments. This work would be helpful to EST-based researches on finding new genes, complementing genome annotation, recognising alternative splicing events and Single Nucleotide Polymorphisms (SNPs), etc.

  7. Development of a EST dataset and characterization of EST-SSRs in a traditional Chinese medicinal plant, Epimedium sagittatum (Sieb. Et Zucc.) Maxim

    PubMed Central

    2010-01-01

    Background Epimedium sagittatum (Sieb. Et Zucc.) Maxim, a traditional Chinese medicinal plant species, has been used extensively as genuine medicinal materials. Certain Epimedium species are endangered due to commercial overexploition, while sustainable application studies, conservation genetics, systematics, and marker-assisted selection (MAS) of Epimedium is less-studied due to the lack of molecular markers. Here, we report a set of expressed sequence tags (ESTs) and simple sequence repeats (SSRs) identified in these ESTs for E. sagittatum. Results cDNAs of E. sagittatum are sequenced using 454 GS-FLX pyrosequencing technology. The raw reads are cleaned and assembled into a total of 76,459 consensus sequences comprising of 17,231 contigs and 59,228 singlets. About 38.5% (29,466) of the consensus sequences significantly match to the non-redundant protein database (E-value < 1e-10), 22,295 of which are further annotated using Gene Ontology (GO) terms. A total of 2,810 EST-SSRs is identified from the Epimedium EST dataset. Trinucleotide SSR is the dominant repeat type (55.2%) followed by dinucleotide (30.4%), tetranuleotide (7.3%), hexanucleotide (4.9%), and pentanucleotide (2.2%) SSR. The dominant repeat motif is AAG/CTT (23.6%) followed by AG/CT (19.3%), ACC/GGT (11.1%), AT/AT (7.5%), and AAC/GTT (5.9%). Thirty-two SSR-ESTs are randomly selected and primer pairs are synthesized for testing the transferability across 52 Epimedium species. Eighteen primer pairs (85.7%) could be successfully transferred to Epimedium species and sixteen of those show high genetic diversity with 0.35 of observed heterozygosity (Ho) and 0.65 of expected heterozygosity (He) and high number of alleles per locus (11.9). Conclusion A large EST dataset with a total of 76,459 consensus sequences is generated, aiming to provide sequence information for deciphering secondary metabolism, especially for flavonoid pathway in Epimedium. A total of 2,810 EST-SSRs is identified from EST dataset and

  8. A global assembly of cotton ESTs

    PubMed Central

    Udall, Joshua A.; Swanson, Jordan M.; Haller, Karl; Rapp, Ryan A.; Sparks, Michael E.; Hatfield, Jamie; Yu, Yeisoo; Wu, Yingru; Dowd, Caitriona; Arpat, Aladdin B.; Sickler, Brad A.; Wilkins, Thea A.; Guo, Jin Ying; Chen, Xiao Ya; Scheffler, Jodi; Taliercio, Earl; Turley, Ricky; McFadden, Helen; Payton, Paxton; Klueva, Natalya; Allen, Randell; Zhang, Deshui; Haigler, Candace; Wilkerson, Curtis; Suo, Jinfeng; Schulze, Stefan R.; Pierce, Margaret L.; Essenberg, Margaret; Kim, HyeRan; Llewellyn, Danny J.; Dennis, Elizabeth S.; Kudrna, David; Wing, Rod; Paterson, Andrew H.; Soderlund, Cari; Wendel, Jonathan F.

    2006-01-01

    Approximately 185,000 Gossypium EST sequences comprising >94,800,000 nucleotides were amassed from 30 cDNA libraries constructed from a variety of tissues and organs under a range of conditions, including drought stress and pathogen challenges. These libraries were derived from allopolyploid cotton (Gossypium hirsutum; AT and DT genomes) as well as its two diploid progenitors, Gossypium arboreum (A genome) and Gossypium raimondii (D genome). ESTs were assembled using the Program for Assembling and Viewing ESTs (PAVE), resulting in 22,030 contigs and 29,077 singletons (51,107 unigenes). Further comparisons among the singletons and contigs led to recognition of 33,665 exemplar sequences that represent a nonredundant set of putative Gossypium genes containing partial or full-length coding regions and usually one or two UTRs. The assembly, along with their UniProt BLASTX hits, GO annotation, and Pfam analysis results, are freely accessible as a public resource for cotton genomics. Because ESTs from diploid and allotetraploid Gossypium were combined in a single assembly, we were in many cases able to bioinformatically distinguish duplicated genes in allotetraploid cotton and assign them to either the A or D genome. The assembly and associated information provide a framework for future investigation of cotton functional and evolutionary genomics. PMID:16478941

  9. Cloning, expression and characterization of two S-ribosylhomocysteine lyases from Lactobacillus plantarum YM-4-3: Implication of conserved and divergent roles in quorum sensing.

    PubMed

    Song, Xiao-Dong; Liu, Chen-Jian; Huang, Shi-Hao; Li, Xiao-Ran; Yang, En; Luo, Yi-Yong

    2018-05-01

    Quorum sensing (QS) is a means of cell-to-cell communication that regulates, via small signalling molecules, expression of a series of genes and controls multicellular behaviour in many bacterial species. The enzyme S-ribosylhomocysteine lyase (LuxS) transforms S-ribosylhomocysteine (SRH) into 4, 5-dihydroxy-2, 3-pentanedione (DPD), the precursor of the interspecies QS signalling molecule autoinducer-2 (AI-2). In this study, two LuxS-coding genes, luxS1 and luxS2, with 70% sequence identity were isolated from Lactobacillus plantarum YM-4-3, and overexpressed in Escherichia coli BL21 (DE3), and the protein products were purified successfully. After incubation of LuxS1 or LuxS2 with SRH, the reaction products were able to induce Vibrio harveyi BB170 bioluminescence, clearly demonstrating that both LuxS1 and LuxS2 synthesize AI-2 from SRH in vitro. Ellman's assay results revealed optimal temperatures for LuxS1 and LuxS2 of 45 and 37 °C, respectively, and their activities were stimulated or inhibited by several metal ions and chemical reagents. In addition, enzyme kinetics data showed that K m , V max and K cat value of LuxS1 for the substrate (SRH) were higher than that of LuxS2. These results suggest that LuxS1 and LuxS2 mediate QS in a temperature-dependent manner and may play conserved roles in AI-2 synthesis but exhibit different activities in response to external environmental stress. To our knowledge, this paper is the first report of two luxS genes present in one bacterial genome and the subsequent comparative elucidation of their functions in AI-2 production. Collectively, our study provides a solid basis for future research concerning the AI-2/LuxS QS system in L. plantarum YM-4-3. Copyright © 2018 Elsevier Inc. All rights reserved.

  10. Analysis of Expressed Sequence Tags (EST) in Date Palm.

    PubMed

    Al-Faifi, Sulieman A; Migdadi, Hussein M; Algamdi, Salem S; Khan, Mohammad Altaf; Al-Obeed, Rashid S; Ammar, Megahed H; Jakse, Jerenj

    2017-01-01

    Expressed sequence tags (EST) were generated from a normalized cDNA library of the date palm Sukkari cv. to understand the high-quality and better field performance of this well-known commercial cultivar. A total of 6943 high-quality ESTs were generated, out of them 6671 are submitted to the GenBank dbEST (LIBEST_028537). The generated ESTs were assembled into 6362 unigenes, consisting of 494 (14.4%) contigs and 5868 (84.53%) singletons. The functional annotation shows that the majority of the ESTs are associated with binding (44%), catalytic (40%), transporter (5%), and structural molecular (5%) activities. The blastx results show that 73% of unigenes are significantly similar to known plant genes and 27% are novel. The latter could be of particular interest in date palm genetic studies. Further analysis shows that some ESTs are categorized as stress/defense- and fruit development-related genes. These newly generated ESTs could significantly enhance date palm EST databases in the public domain and are available to scientists and researchers across the globe. This knowledge will facilitate the discovery of candidate genes that govern important developmental and agronomical traits in date palm. It will provide important resources for developing genetic tools, comparative genomics, and genome evolution among date palm cultivars.

  11. The Pea Photoperiod Response Gene STERILE NODES Is an Ortholog of LUX ARRHYTHMO1[W][OPEN

    PubMed Central

    Liew, Lim Chee; Hecht, Valérie; Sussmilch, Frances C.; Weller, James L.

    2014-01-01

    The STERILE NODES (SN) locus in pea (Pisum sativum) was one of the first photoperiod response genes to be described and provided early evidence for the genetic control of long-distance signaling in flowering-time regulation. Lines homozygous for recessive sn mutations are early flowering and photoperiod insensitive, with an increased ability to promote flowering across a graft union in short-day conditions. Here, we show that SN controls developmental regulation of genes in the FT family and rhythmic regulation of genes related to circadian clock function. Using a positional and functional candidate approach, we identify SN as the pea ortholog of LUX ARRHYTHMO, a GARP transcription factor from Arabidopsis (Arabidopsis thaliana) with an important role in circadian clock function. In addition to induced mutants, sequence analysis demonstrates the presence of at least three other independent, naturally occurring loss-of-function mutations among known sn cultivars. Examination of genetic and regulatory interactions between SN and two other circadian clock genes, HIGH RESPONSE TO PHOTOPERIOD (HR) and DIE NEUTRALIS (DNE), suggests a complex relationship in which HR regulates expression of SN and the role of DNE and HR in control of flowering is dependent on SN. These results extend previous work to show that pea orthologs of all three Arabidopsis evening complex genes regulate clock function and photoperiod-responsive flowering and suggest that the function of these genes may be widely conserved. PMID:24706549

  12. Paclitaxel-Coated Balloon in Infrapopliteal Arteries: 12-Month Results From the BIOLUX P-II Randomized Trial (BIOTRONIK'S-First in Man study of the Passeo-18 LUX drug releasing PTA Balloon Catheter vs. the uncoated Passeo-18 PTA balloon catheter in subjects requiring revascularization of infrapopliteal arteries).

    PubMed

    Zeller, Thomas; Beschorner, Ulrich; Pilger, Ernst; Bosiers, Marc; Deloose, Koen; Peeters, Patrick; Scheinert, Dierk; Schulte, Karl-Ludwig; Rastan, Aljoscha; Brodmann, Marianne

    2015-10-01

    The aim of BIOLUX P-II (BIOTRONIK'S-First in Man study of the Passeo-18 LUX drug releasing PTA Balloon Catheter vs. the uncoated Passeo-18 PTA balloon catheter in subjects requiring revascularization of infrapopliteal arteries) trial was to compare the safety and efficacy of a novel paclitaxel-coated drug-eluting balloon (DEB) versus an uncoated balloon (percutaneous transluminal angioplasty [PTA]) in de novo or native restenotic lesions of the infrapopliteal arteries in patients with claudication and critical limb ischemia. DEB have shown promising results in femoropopliteal lesions, but data for infrapopliteal lesions are scarce. In this prospective, multicenter, randomized first-in-man study, 72 patients were randomized 1:1 to either a Passeo-18 Lux DEB (Biotronik AG, Buelach, Switzerland) (n = 36) or Passeo-18 PTA (n = 36). Follow-up assessments were scheduled at 1, 6, and 12 months, with angiographic assessment at 6 months. Adverse events were adjudicated by an independent clinical events committee, and angiographic parameters were assessed by an independent core laboratory. The primary safety endpoint (a composite of all-cause mortality, target extremity major amputation, target lesion thrombosis, and target vessel revascularization at 30 days) was 0% in the DEB group versus 8.3% in the PTA group (p = 0.239). The primary performance endpoint (patency loss at 6 months) was 17.1% in the DEB group versus 26.1% in the PTA group (p = 0.298), and major amputations of the target extremity occurred in 3.3% versus 5.6% of the patients at 12 months, respectively. The Passeo-18 Lux DEB has been proven to be safe and effective in infrapopliteal lesions with comparable outcomes to PTA. Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  13. ESAP plus: a web-based server for EST-SSR marker development.

    PubMed

    Ponyared, Piyarat; Ponsawat, Jiradej; Tongsima, Sissades; Seresangtakul, Pusadee; Akkasaeng, Chutipong; Tantisuwichwong, Nathpapat

    2016-12-22

    Simple sequence repeats (SSRs) have become widely used as molecular markers in plant genetic studies due to their abundance, high allelic variation at each locus and simplicity to analyze using conventional PCR amplification. To study plants with unknown genome sequence, SSR markers from Expressed Sequence Tags (ESTs), which can be obtained from the plant mRNA (converted to cDNA), must be utilized. With the advent of high-throughput sequencing technology, huge EST sequence data have been generated and are now accessible from many public databases. However, SSR marker identification from a large in-house or public EST collection requires a computational pipeline that makes use of several standard bioinformatic tools to design high quality EST-SSR primers. Some of these computational tools are not users friendly and must be tightly integrated with reference genomic databases. A web-based bioinformatic pipeline, called EST Analysis Pipeline Plus (ESAP Plus), was constructed for assisting researchers to develop SSR markers from a large EST collection. ESAP Plus incorporates several bioinformatic scripts and some useful standard software tools necessary for the four main procedures of EST-SSR marker development, namely 1) pre-processing, 2) clustering and assembly, 3) SSR mining and 4) SSR primer design. The proposed pipeline also provides two alternative steps for reducing EST redundancy and identifying SSR loci. Using public sugarcane ESTs, ESAP Plus automatically executed the aforementioned computational pipeline via a simple web user interface, which was implemented using standard PHP, HTML, CSS and Java scripts. With ESAP Plus, users can upload raw EST data and choose various filtering options and parameters to analyze each of the four main procedures through this web interface. All input EST data and their predicted SSR results will be stored in the ESAP Plus MySQL database. Users will be notified via e-mail when the automatic process is completed and they can

  14. A Bayesian nonparametric method for prediction in EST analysis

    PubMed Central

    Lijoi, Antonio; Mena, Ramsés H; Prünster, Igor

    2007-01-01

    Background Expressed sequence tags (ESTs) analyses are a fundamental tool for gene identification in organisms. Given a preliminary EST sample from a certain library, several statistical prediction problems arise. In particular, it is of interest to estimate how many new genes can be detected in a future EST sample of given size and also to determine the gene discovery rate: these estimates represent the basis for deciding whether to proceed sequencing the library and, in case of a positive decision, a guideline for selecting the size of the new sample. Such information is also useful for establishing sequencing efficiency in experimental design and for measuring the degree of redundancy of an EST library. Results In this work we propose a Bayesian nonparametric approach for tackling statistical problems related to EST surveys. In particular, we provide estimates for: a) the coverage, defined as the proportion of unique genes in the library represented in the given sample of reads; b) the number of new unique genes to be observed in a future sample; c) the discovery rate of new genes as a function of the future sample size. The Bayesian nonparametric model we adopt conveys, in a statistically rigorous way, the available information into prediction. Our proposal has appealing properties over frequentist nonparametric methods, which become unstable when prediction is required for large future samples. EST libraries, previously studied with frequentist methods, are analyzed in detail. Conclusion The Bayesian nonparametric approach we undertake yields valuable tools for gene capture and prediction in EST libraries. The estimators we obtain do not feature the kind of drawbacks associated with frequentist estimators and are reliable for any size of the additional sample. PMID:17868445

  15. Wheat EST resources for functional genomics of abiotic stress

    PubMed Central

    Houde, Mario; Belcaid, Mahdi; Ouellet, François; Danyluk, Jean; Monroy, Antonio F; Dryanova, Ani; Gulick, Patrick; Bergeron, Anne; Laroche, André; Links, Matthew G; MacCarthy, Luke; Crosby, William L; Sarhan, Fathey

    2006-01-01

    Background Wheat is an excellent species to study freezing tolerance and other abiotic stresses. However, the sequence of the wheat genome has not been completely characterized due to its complexity and large size. To circumvent this obstacle and identify genes involved in cold acclimation and associated stresses, a large scale EST sequencing approach was undertaken by the Functional Genomics of Abiotic Stress (FGAS) project. Results We generated 73,521 quality-filtered ESTs from eleven cDNA libraries constructed from wheat plants exposed to various abiotic stresses and at different developmental stages. In addition, 196,041 ESTs for which tracefiles were available from the National Science Foundation wheat EST sequencing program and DuPont were also quality-filtered and used in the analysis. Clustering of the combined ESTs with d2_cluster and TGICL yielded a few large clusters containing several thousand ESTs that were refractory to routine clustering techniques. To resolve this problem, the sequence proximity and "bridges" were identified by an e-value distance graph to manually break clusters into smaller groups. Assembly of the resolved ESTs generated a 75,488 unique sequence set (31,580 contigs and 43,908 singletons/singlets). Digital expression analyses indicated that the FGAS dataset is enriched in stress-regulated genes compared to the other public datasets. Over 43% of the unique sequence set was annotated and classified into functional categories according to Gene Ontology. Conclusion We have annotated 29,556 different sequences, an almost 5-fold increase in annotated sequences compared to the available wheat public databases. Digital expression analysis combined with gene annotation helped in the identification of several pathways associated with abiotic stress. The genomic resources and knowledge developed by this project will contribute to a better understanding of the different mechanisms that govern stress tolerance in wheat and other cereals. PMID

  16. Continuous wave and passively Q-switched laser performance of Nd:LuxGd3-xGa5O12 crystal at 1062 nm

    NASA Astrophysics Data System (ADS)

    Fu, X. W.; Jia, Z. T.; Yang, H.; Li, Y. B.; Yuan, D. S.; Zhang, B. T.; Dong, C. M.; He, J. L.; Tao, X. T.

    2012-12-01

    Continuous wave (CW) and passively Q-switched (PQS) laser properties at 1062 nm of the Nd:LuxGd3-xGa5O12 (Nd:LGGG) disordered crystal have been demonstrated. The doping concentrations of Nd3+ and Lu3+ in the as obtained crystal were measured to be 0.96 and 0.66 at.%, respectively. In the CW regime, the output power of 9.73 W was obtained with an optical-to-optical efficiency as high as 60.7% and slope efficiency of 61.2%. During the passively Q-switched operation, the maximum output power of 1.24 W was achieved under the absorbed pump power of 6.86 W. The maximum peak power of 14.20 kW and single pulse energy of 148 μJ were obtained with the Toc = 10% under the absorbed pump power of 6.36 W. The results are much better than those obtained with Nd:LGGG crystal doped with 13.6 at.% Lu3+ and 0.53 at.% Nd3+ ions.

  17. Rapid in silico cloning of genes using expressed sequence tags (ESTs).

    PubMed

    Gill, R W; Sanseau, P

    2000-01-01

    Expressed sequence tags (ESTs) are short single-pass DNA sequences obtained from either end of cDNA clones. These ESTs are derived from a vast number of cDNA libraries obtained from different species. Human ESTs are the bulk of the data and have been widely used to identify new members of gene families, as markers on the human chromosomes, to discover polymorphism sites and to compare expression patterns in different tissues or pathologies states. Information strategies have been devised to query EST databases. Since most of the analysis is performed with a computer, the term "in silico" strategy has been coined. In this chapter we will review the current status of EST databases, the pros and cons of EST-type data and describe possible strategies to retrieve meaningful information.

  18. Analysis of SSR information in EST resources of sugarcane

    USDA-ARS?s Scientific Manuscript database

    Expressed sequence tags ( ESTs) offer the opportunity to exploit single, low -copy, conserved sequence motifs for the development of simple sequence repeats ( SSRs). The total of 262 113 ESTs of sugarcane (Saccharum officinarum) in the database of NCBI were downloaded and analyzed, which resulted in...

  19. Launch of STS-63 Discovery

    NASA Technical Reports Server (NTRS)

    1995-01-01

    This wide lux image of the Space Shuttle Discovery as it began its race to catch up with Russia's Mir Space Station shows the base of the launch pad as well as the orbiter just clearing the gantry. Liftoff from Launch Pad 39B, Kennedy Space Center (KSC) occurred at 12:22:04 (EST) February 3, 1995. Discovery is the first in the current fleet of four space shuttle vehicles to make 20 launches.

  20. A functional whole blood assay to measure viability of mycobacteria, using reporter-gene tagged BCG or M.Tb (BCGlux/M.Tb lux).

    PubMed

    Newton, Sandra; Martineau, Adrian; Kampmann, Beate

    2011-09-14

    employed in studies of adults and children in TB-endemic settings. We have shown immunogenicity of the BCG vaccine, increased growth of mycobacteria in HIV-positive patients, as well as the effect of anti-retroviral therapy and Vitamin D on mycobacterial survival in vitro. Here we summarise the methodology, and present our reproducibility data using this relatively simple, low-cost and field-friendly model. Note: Definitions/Abbreviations BCG lux = M. bovis BCG, Montreal strain, transformed with shuttle plasmid pSMT1 carrying the luxAB genes from Vibrio harveyi, under the control of the mycobacterial GroEL (hsp60) promoter. CFU = Colony Forming Unit (a measure of mycobacterial viability).

  1. From deep-sea volcanoes to human pathogens: a conserved quorum-sensing signal in Epsilonproteobacteria

    PubMed Central

    Pérez-Rodríguez, Ileana; Bolognini, Marie; Ricci, Jessica; Bini, Elisabetta; Vetriani, Costantino

    2015-01-01

    Chemosynthetic Epsilonproteobacteria from deep-sea hydrothermal vents colonize substrates exposed to steep thermal and redox gradients. In many bacteria, substrate attachment, biofilm formation, expression of virulence genes and host colonization are partly controlled via a cell density-dependent mechanism involving signal molecules, known as quorum sensing. Within the Epsilonproteobacteria, quorum sensing has been investigated only in human pathogens that use the luxS/autoinducer-2 (AI-2) mechanism to control the expression of some of these functions. In this study we showed that luxS is conserved in Epsilonproteobacteria and that pathogenic and mesophilic members of this class inherited this gene from a thermophilic ancestor. Furthermore, we provide evidence that the luxS gene is expressed—and a quorum-sensing signal is produced—during growth of Sulfurovum lithotrophicum and Caminibacter mediatlanticus, two Epsilonproteobacteria from deep-sea hydrothermal vents. Finally, we detected luxS transcripts in Epsilonproteobacteria-dominated biofilm communities collected from deep-sea hydrothermal vents. Taken together, our findings indicate that the epsiloproteobacterial lineage of the LuxS enzyme originated in high-temperature geothermal environments and that, in vent Epsilonproteobacteria, luxS expression is linked to the production of AI-2 signals, which are likely produced in situ at deep-sea vents. We conclude that the luxS gene is part of the ancestral epsilonproteobacterial genome and represents an evolutionary link that connects thermophiles to human pathogens. PMID:25397946

  2. From deep-sea volcanoes to human pathogens: a conserved quorum-sensing signal in Epsilonproteobacteria.

    PubMed

    Pérez-Rodríguez, Ileana; Bolognini, Marie; Ricci, Jessica; Bini, Elisabetta; Vetriani, Costantino

    2015-05-01

    Chemosynthetic Epsilonproteobacteria from deep-sea hydrothermal vents colonize substrates exposed to steep thermal and redox gradients. In many bacteria, substrate attachment, biofilm formation, expression of virulence genes and host colonization are partly controlled via a cell density-dependent mechanism involving signal molecules, known as quorum sensing. Within the Epsilonproteobacteria, quorum sensing has been investigated only in human pathogens that use the luxS/autoinducer-2 (AI-2) mechanism to control the expression of some of these functions. In this study we showed that luxS is conserved in Epsilonproteobacteria and that pathogenic and mesophilic members of this class inherited this gene from a thermophilic ancestor. Furthermore, we provide evidence that the luxS gene is expressed--and a quorum-sensing signal is produced--during growth of Sulfurovum lithotrophicum and Caminibacter mediatlanticus, two Epsilonproteobacteria from deep-sea hydrothermal vents. Finally, we detected luxS transcripts in Epsilonproteobacteria-dominated biofilm communities collected from deep-sea hydrothermal vents. Taken together, our findings indicate that the epsiloproteobacterial lineage of the LuxS enzyme originated in high-temperature geothermal environments and that, in vent Epsilonproteobacteria, luxS expression is linked to the production of AI-2 signals, which are likely produced in situ at deep-sea vents. We conclude that the luxS gene is part of the ancestral epsilonproteobacterial genome and represents an evolutionary link that connects thermophiles to human pathogens.

  3. AFT-QuEST Consortium Yearbook. Proceedings of the QuEST Consortium (April 2-6, 1972).

    ERIC Educational Resources Information Center

    American Federation of Teachers, Washington, DC.

    This book contains the proceedings from the QuEST Consortium held on April 2-6, 1972, which focused on problems of method and technique in teaching as well as on resource organization. The program schedule for the Consortium is presented with the following goals: (a) investigation of educational policy issues, action programs, and projects and (b)…

  4. A Real-Time Non-invasive Auto-bioluminescent Urinary Bladder Cancer Xenograft Model.

    PubMed

    John, Bincy Anu; Xu, Tingting; Ripp, Steven; Wang, Hwa-Chain Robert

    2017-02-01

    The study was to develop an auto-bioluminescent urinary bladder cancer (UBC) xenograft animal model for pre-clinical research. The study used a humanized, bacteria-originated lux reporter system consisting of six (luxCDABEfrp) genes to express components required for producing bioluminescent signals in human UBC J82, J82-Ras, and SW780 cells without exogenous substrates. Immune-deficient nude mice were inoculated with Lux-expressing UBC cells to develop auto-bioluminescent xenograft tumors that were monitored by imaging and physical examination. Lux-expressing auto-bioluminescent J82-Lux, J82-Ras-Lux, and SW780-Lux cell lines were established. Xenograft tumors derived from tumorigenic Lux-expressing auto-bioluminescent J82-Ras-Lux cells allowed a serial, non-invasive, real-time monitoring by imaging of tumor development prior to the presence of palpable tumors in animals. Using Lux-expressing auto-bioluminescent tumorigenic cells enabled us to monitor the entire course of xenograft tumor development through tumor cell implantation, adaptation, and growth to visible/palpable tumors in animals.

  5. Sequence analysis of 497 mouse brain ESTs expressed in the substantia nigra

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stewart, G.J.; Savioz, A.; Davies, R.W.

    1997-01-15

    The use of subtracted, region-specific cDNA libraries combined with single-pass cDNA sequencing allows the discovery of novel genes and facilitates molecular description of the tissue or region involved. We report the sequence of 497 mouse expressed sequence tags (ESTs) from two subtracted libraries enriched for cDNAs expressed in the substantia nigra, a brain region with important roles in movement control and Parkinson disease. Of these, 238 ESTs give no database matches and therefore derive from novel genes. A further 115 ESTs show sequence similarity to ESTs from other organisms, which themselves do not yield any significant database matches to genesmore » of known function. Fifty-six ESTs show sequence similarity to previously identified genes whose mouse homologues have not been reported. The total number of ESTs reported that are new for the mouse is 407, which, together with the 90 ESTs corresponding to known mouse genes or cDNAs, contributes to the molecular description of the substantia nigra. 21 refs., 4 tabs.« less

  6. Enhancement/upgrade of Engine Structures Technology Best Estimator (EST/BEST) Software System

    NASA Technical Reports Server (NTRS)

    Shah, Ashwin

    2003-01-01

    This report describes the work performed during the contract period and the capabilities included in the EST/BEST software system. The developed EST/BEST software system includes the integrated NESSUS, IPACS, COBSTRAN, and ALCCA computer codes required to perform the engine cycle mission and component structural analysis. Also, the interactive input generator for NESSUS, IPACS, and COBSTRAN computer codes have been developed and integrated with the EST/BEST software system. The input generator allows the user to create input from scratch as well as edit existing input files interactively. Since it has been integrated with the EST/BEST software system, it enables the user to modify EST/BEST generated files and perform the analysis to evaluate the benefits. Appendix A gives details of how to use the newly added features in the EST/BEST software system.

  7. Visible light exposure reduces the drip loss of fresh-cut watermelon.

    PubMed

    Wang, Yubin; Li, Wu; Cai, Wenqian; Ma, Yue; Xu, Yong; Zhao, Xiaoyan; Zhang, Chao

    2018-05-01

    Drip loss of fresh-cut watermelon has become a concern for both producers and consumers. The effect of visible light exposure on the drip loss of fresh-cut watermelon was evaluated. Visible light treatments of 3000 and 10 Lux were applied to fresh-cut watermelon at 4 °C during the shelf life for 5 days, with light exposure of 150 Lux as the control. The drip loss of the fresh-cut watermelon at 3000 Lux was 74.8% of that at 150 Lux on the fifth day, and the moisture evaporation at 3000 Lux was 1.89 times that at 150 Lux. Moreover, the light exposure of 3000 Lux reduced the activity of polygalacturonase, which is a key hydrolase related to cell wall degradation. The cell wall degradation ratio of the fresh-cut watermelon at 3000 Lux was 81.7% of that at 150 Lux on the fifth day. Overall, light exposure of 3000 Lux reduced drip loss by accelerating moisture evaporation in fresh-cut watermelon, as well as by reducing the activity of polygalacturonase and the ratio of cell wall degradation. Hence, exposing the fresh-cut watermelon to visible light of 3000 Lux during the shelf life was a feasible way of reducing drip loss.

  8. AFT-QuEST Consortium Yearbook. Proceedings of the AFT-QuEST Consortium (April 22-26, 1973).

    ERIC Educational Resources Information Center

    American Federation of Teachers, Washington, DC.

    This document is a report on the proceedings of the 1973 American Federation of Teachers-Quality Educational Standards in Teaching (AFT-QuEST) consortium sponsored by the AFT. Included in this document are the texts of speeches and outlines of workshops and iscussions. The document is divided into the following sections: goals, major proposals,…

  9. The construction of an EST database for Bombyx mori and its application

    PubMed Central

    Mita, Kazuei; Morimyo, Mitsuoki; Okano, Kazuhiro; Koike, Yoshiko; Nohata, Junko; Kawasaki, Hideki; Kadono-Okuda, Keiko; Yamamoto, Kimiko; Suzuki, Masataka G.; Shimada, Toru; Goldsmith, Marian R.; Maeda, Susumu

    2003-01-01

    To build a foundation for the complete genome analysis of Bombyx mori, we have constructed an EST database. Because gene expression patterns deeply depend on tissues as well as developmental stages, we analyzed many cDNA libraries prepared from various tissues and different developmental stages to cover the entire set of Bombyx genes. So far, the Bombyx EST database contains 35,000 ESTs from 36 cDNA libraries, which are grouped into ≈11,000 nonredundant ESTs with the average length of 1.25 kb. The comparison with FlyBase suggests that the present EST database, SilkBase, covers >55% of all genes of Bombyx. The fraction of library-specific ESTs in each cDNA library indicates that we have not yet reached saturation, showing the validity of our strategy for constructing an EST database to cover all genes. To tackle the coming saturation problem, we have checked two methods, subtraction and normalization, to increase coverage and decrease the number of housekeeping genes, resulting in a 5–11% increase of library-specific ESTs. The identification of a number of genes and comprehensive cloning of gene families have already emerged from the SilkBase search. Direct links of SilkBase with FlyBase and WormBase provide ready identification of candidate Lepidoptera-specific genes. PMID:14614147

  10. Mining SNPs from EST sequences using filters and ensemble classifiers.

    PubMed

    Wang, J; Zou, Q; Guo, M Z

    2010-05-04

    Abundant single nucleotide polymorphisms (SNPs) provide the most complete information for genome-wide association studies. However, due to the bottleneck of manual discovery of putative SNPs and the inaccessibility of the original sequencing reads, it is essential to develop a more efficient and accurate computational method for automated SNP detection. We propose a novel computational method to rapidly find true SNPs in public-available EST (expressed sequence tag) databases; this method is implemented as SNPDigger. EST sequences are clustered and aligned. SNP candidates are then obtained according to a measure of redundant frequency. Several new informative biological features, such as the structural neighbor profiles and the physical position of the SNP, were extracted from EST sequences, and the effectiveness of these features was demonstrated. An ensemble classifier, which employs a carefully selected feature set, was included for the imbalanced training data. The sensitivity and specificity of our method both exceeded 80% for human genetic data in the cross validation. Our method enables detection of SNPs from the user's own EST dataset and can be used on species for which there is no genome data. Our tests showed that this method can effectively guide SNP discovery in ESTs and will be useful to avoid and save the cost of biological analyses.

  11. Heterologous Expression of sahH Reveals That Biofilm Formation Is Autoinducer-2-independent in Streptococcus sanguinis but Is Associated with an Intact Activated Methionine Cycle*

    PubMed Central

    Redanz, Sylvio; Standar, Kerstin; Podbielski, Andreas; Kreikemeyer, Bernd

    2012-01-01

    Numerous studies have claimed deleterious effects of LuxS mutation on many bacterial phenotypes, including bacterial biofilm formation. Genetic complementation mostly restored the observed mutant phenotypes to WT levels, leading to the postulation that quorum sensing via a family of molecules generically termed autoinducer-2 (AI-2) is essential for many phenotypes. Because LuxS mutation has dual effects, this hypothesis needs to be investigated into the details for each bacterial species. In this study we used S. sanguinis SK36 as a model biofilm bacterium and employed physiological characterization and transcriptome approaches on WT and luxS-deficient strains, in combination with chemical, luxS, and sahH complementation experiments. SahH enables a direct conversion of SAH to homocysteine and thereby restores the activated methionine cycle in a luxS-negative background without formation of the AI-2 precursor 4,5-dihydroxy-2,3-pentanedione. With this strategy we were able to dissect the individual contribution of LuxS and AI-2 activity in detail. Our data revealed that S. sanguinis biofilm formation is independent from AI-2 substance pools and is rather supported by an intact activated methyl cycle. Of 216 differentially transcribed genes in the luxS mutant, 209 were restored by complementation with a gene encoding the S-adenosylhomocysteine hydrolase. Only nine genes, mainly involved in natural competence, were directly affected by the AI-2 quorum-sensing substance pool. Cumulatively, this suggested that biofilm formation in S. sanguinis is not under control of AI-2. Our study suggests that previously evaluated LuxS mutants in other species need to be revisited to resolve the precise contribution of AI-2 substance pools and the methionine pathways. PMID:22942290

  12. Two EST-derived marker systems for cultivar identification in tree peony.

    PubMed

    Zhang, J J; Shu, Q Y; Liu, Z A; Ren, H X; Wang, L S; De Keyser, E

    2012-02-01

    Tree peony (Paeonia suffruticosa Andrews), a woody deciduous shrub, belongs to the section Moutan DC. in the genus of Paeonia of the Paeoniaceae family. To increase the efficiency of breeding, two EST-derived marker systems were developed based on a tree peony expressed sequence tag (EST) database. Using target region amplification polymorphism (TRAP), 19 of 39 primer pairs showed good amplification for 56 accessions with amplicons ranging from 120 to 3,000 bp long, among which 99.3% were polymorphic. In contrast, 7 of 21 primer pairs demonstrated adequate amplification with clear bands for simple sequence repeats (SSRs) developed from ESTs, and a total of 33 alleles were found in 56 accessions. The similarity matrices generated by TRAP and EST-SSR markers were compared, and the Mantel test (r = 0.57778, P = 0.0020) showed a moderate correlation between the two types of molecular markers. TRAP markers were suitable for DNA fingerprinting and EST-SSR markers were more appropriate for discriminating synonyms (the same cultivars with different names due to limited information exchanged among different geographic areas). The two sets of EST-derived markers will be used further for genetic linkage map construction and quantitative trait locus detection in tree peony.

  13. Development of an Expressed Sequence Tag (EST) Resource for Wheat (Triticum aestivum L.)

    PubMed Central

    Lazo, G. R.; Chao, S.; Hummel, D. D.; Edwards, H.; Crossman, C. C.; Lui, N.; Matthews, D. E.; Carollo, V. L.; Hane, D. L.; You, F. M.; Butler, G. E.; Miller, R. E.; Close, T. J.; Peng, J. H.; Lapitan, N. L. V.; Gustafson, J. P.; Qi, L. L.; Echalier, B.; Gill, B. S.; Dilbirligi, M.; Randhawa, H. S.; Gill, K. S.; Greene, R. A.; Sorrells, M. E.; Akhunov, E. D.; Dvořák, J.; Linkiewicz, A. M.; Dubcovsky, J.; Hossain, K. G.; Kalavacharla, V.; Kianian, S. F.; Mahmoud, A. A.; Miftahudin; Ma, X.-F.; Conley, E. J.; Anderson, J. A.; Pathan, M. S.; Nguyen, H. T.; McGuire, P. E.; Qualset, C. O.; Anderson, O. D.

    2004-01-01

    This report describes the rationale, approaches, organization, and resource development leading to a large-scale deletion bin map of the hexaploid (2n = 6x = 42) wheat genome (Triticum aestivum L.). Accompanying reports in this issue detail results from chromosome bin-mapping of expressed sequence tags (ESTs) representing genes onto the seven homoeologous chromosome groups and a global analysis of the entire mapped wheat EST data set. Among the resources developed were the first extensive public wheat EST collection (113,220 ESTs). Described are protocols for sequencing, sequence processing, EST nomenclature, and the assembly of ESTs into contigs. These contigs plus singletons (unassembled ESTs) were used for selection of distinct sequence motif unigenes. Selected ESTs were rearrayed, validated by 5′ and 3′ sequencing, and amplified for probing a series of wheat aneuploid and deletion stocks. Images and data for all Southern hybridizations were deposited in databases and were used by the coordinators for each of the seven homoeologous chromosome groups to validate the mapping results. Results from this project have established the foundation for future developments in wheat genomics. PMID:15514037

  14. Light intensity of curved laryngoscope blades in Philadelphia emergency departments.

    PubMed

    Levitan, Richard M; Kelly, John J; Kinkle, William C; Fasano, Charles

    2007-09-01

    Laryngoscopy and tracheal intubation requires laryngeal exposure and illumination. The objective of this study is to assess variation in laryngoscope lights across different emergency departments (EDs). A convenience sample of 3 Mac #4 blade and handle pairs in each of 17 Philadelphia area EDs was tested with a digital light meter to derive the median lux at the distal tip. For each blade tested, we characterized blade design (American, English, or German) and light type (fiber-illuminated versus conventional bulb-on-blade) and measured light-to-tip distance. A total of 50 blades and handle pairs were tested (one ED had only 2 Mac #4 blades). American designs were the most common (38/50), followed by English (6/50) and German (3/50) designs. Three blades had hybrid design features and acrylic light-conducting fibers. Median luminance varied from 11 lux to 5,627 lux. The glass fiber-illuminated blades (n=13) produced greater luminance (median 1,205 lux; interquartile range [IQR] 726 to 2,176 lux) than bulb-on-blade designs (median 689 lux; IQR 290 to 906 lux). German fiber-illuminated blades produced the highest luminance (median 1,937 lux; IQR 1,453 to 3,782 lux). English bulb-on-blade designs produced more luminance (median 915 lux; IQR 745 to 1270 lux) than American (median 689 lux; IQR 269 to 807 lux). German and English blades had shorter light-to-tip distances (median 51 mm and 47 mm, respectively) than American blades (65 mm). Curved laryngoscope blades in different EDs have marked variation in light intensity. The contribution of luminance to laryngoscopy performance warrants investigation.

  15. Iron control of the Vibrio fischeri luminescence system in Escherichia coli.

    PubMed

    Dunlap, P V

    1992-01-01

    Iron influences luminescence in Vibrio fischeri; cultures iron-restricted for growth rate induce luminescence at a lower optical density (OD) than faster growing, iron-replete cultures. An iron restriction effect analogous to that in V. fischeri (slower growth, induction of luminescence at a lower OD) was established using Escherichia coli tonB and tonB+ strains transformed with recombinant plasmids containing the V. fischeri lux genes (luxR luxICDABEG) and grown in the presence and absence of the iron chelator ethylenediamine-di(o-hydroxylphenyl acetic acid) (EDDHA). This permitted the mechanism of iron control of luminescence to be examined. A fur mutant and its parent strain containing the intact lux genes exhibited no difference in the OD at induction of luminescence. Therefore, an iron-binding repressor protein apparently is not involved in iron control of luminescence. Furthermore, in the tonB and in tonB+ strains containing lux plasmids with Mu dI(lacZ) fusions in luxR, levels of beta-galactosidase activity (expression from the luxR promoter) and luciferase activity (expression from the luxICDABEG promoter) both increased by a similar amount (8-9 fold each for tonB, 2-3 fold each for tonB+) in the presence of EDDHA. Similar results were obtained with the luxR gene present on a complementing plasmid. The previously identified regulatory factors that control the lux system (autoinducer-LuxR protein, cyclic AMP-cAMP receptor protein) differentially control expression from the luxR and luxICDABEG promoters, increasing expression from one while decreasing expression from the other. Consequently, these results suggest that the effect of iron on the V. fischeri luminescence system is indirect.

  16. SEAN: SNP prediction and display program utilizing EST sequence clusters.

    PubMed

    Huntley, Derek; Baldo, Angela; Johri, Saurabh; Sergot, Marek

    2006-02-15

    SEAN is an application that predicts single nucleotide polymorphisms (SNPs) using multiple sequence alignments produced from expressed sequence tag (EST) clusters. The algorithm uses rules of sequence identity and SNP abundance to determine the quality of the prediction. A Java viewer is provided to display the EST alignments and predicted SNPs.

  17. EGFR mutation detection in circulating cell-free DNA of lung adenocarcinoma patients: analysis of LUX-Lung 3 and 6

    PubMed Central

    Wu, Yi-Long; Sequist, Lecia V; Hu, Cheng-Ping; Feng, Jifeng; Lu, Shun; Huang, Yunchao; Li, Wei; Hou, Mei; Schuler, Martin; Mok, Tony; Yamamoto, Nobuyuki; O'Byrne, Kenneth; Hirsh, Vera; Gibson, Neil; Massey, Dan; Kim, Miyoung; Yang, James Chih-Hsin

    2017-01-01

    Background: In the Phase III LUX-Lung 3/6 (LL3/LL6) trials in epidermal growth factor receptor (EGFR) mutation-positive lung adenocarcinoma patients, we evaluated feasibility of EGFR mutation detection using circulating cell-free DNA (cfDNA) and prognostic and predictive utility of cfDNA positivity (cfDNA+). Methods: Paired tumour and blood samples were prospectively collected from randomised patients. Mutations were detected using cfDNA from serum (LL3) or plasma (LL6) by a validated allele-specific quantitative real-time PCR kit. Results: EGFR mutation detection rates in cfDNA were 28.6% (serum) and 60.5% (plasma). Mutation detection in blood was associated with advanced disease characteristics, including higher performance score, number of metastatic sites and bone/liver metastases, and poorer prognosis. In patients with common EGFR mutations, afatinib improved progression-free survival vs chemotherapy in cfDNA+ (LL3: HR, 0.35; P=0.0009; LL6: HR, 0.25; P<0.0001) and cfDNA− (LL3: HR, 0.46; P<0.0001; LL6: HR, 0.12; P<0.0001) cohorts. A trend towards overall survival benefit with afatinib was observed in cfDNA+ patients. Conclusions: Plasma cfDNA is a promising alternative to biopsy for EGFR testing. Detectable mutation in blood was associated with more advanced disease and poorer prognosis. Afatinib improved outcomes in EGFR mutation-positive patients regardless of blood mutation status. PMID:28006816

  18. Effects of different light intensities in the morning on dim light melatonin onset.

    PubMed

    Kozaki, Tomoaki; Toda, Naohiro; Noguchi, Hiroki; Yasukouchi, Akira

    2011-01-01

    The present study evaluated the effects of exposure to light intensity in the morning on dim light melatonin onset (DLMO). The tested light intensities were 750 lux, 150 lux, 3000 lux, 6000 lux and 12,000 lux (horizontal illuminance at cornea), using commercial 5000 K fluorescent lamps. Eleven healthy males aged 21-31 participated in 2-day experiments for each light condition. On the first experimental day (day 1), subjects were exposed to dim light (<30 lux) for 3 h in the morning (09:00-12:00). On the same day, saliva samples were taken in dim light (<30 lux) every 30 min from 21:00 to 01:00 to determine the DLMO phase. The subjects were allowed to sleep from 01:00 to 08:00. On the second experimental day (day 2), the subjects were exposed to experimental light conditions for 3 h in the morning. The experimental schedule after light exposure was the same as on day 1. On comparing day 2 with day 1, significant phase advances of DLMO were obtained at 3000 lux, 6000 lux and 12,000 lux. These findings indicate that exposure to a necessary intensity from an ordinary light source, such as a fluorescent lamp, in the morning within one day affects melatonin secretion.

  19. Construction of new EST-SSRs for Fusarium resistant wheat breeding.

    PubMed

    Yumurtaci, Aysen; Sipahi, Hulya; Al-Abdallat, Ayed; Jighly, Abdulqader; Baum, Michael

    2017-06-01

    Surveying Fusarium resistance in wheat with easy applicable molecular markers such as simple sequence repeats (SSRs) is a prerequest for molecular breeding. Expressed sequence tags (ESTs) are one of the main sources for development of new SSR candidates. Therefore, 18.292 publicly available wheat ESTs were mined and genotyping of newly developed 55 EST-SSR derived primer pairs produced clear fragments in ten wheat cultivars carrying different levels of Fusarium resistance. Among the proved markers, 23 polymorphic EST-SSRs were obtained and related alleles were mostly found on B and D genome. Based on the fragment profiling and similarity analysis, a 327bp amplicon, which was a product of contig 1207 (chromosome 5BL), was detected only in Fusarium head blight (FHB) resistant cultivars (CM82036 and Sumai) and the amino acid sequences showed a similarity to pathogen related proteins. Another FHB resistance related EST-SSR, Contig 556 (chromosome 1BL) produced a 151bp fragment in Sumai and was associated to wax2-like protein. A polymorphic 204bp fragment, derived from Contig 578 (chromosome 1DL), was generated from root rot (FRR) resistant cultivars (2-49; Altay2000 and Sunco). A total of 98 alleles were displayed with an average of 1.8 alleles per locus and the polymorphic information content (PIC) ranged from 0.11 to 0.78. Dendrogram tree with two main and five sub-groups were displayed the highest genetic relationship between FRR resistant cultivars (2-49 and Altay2000), FRR sensitive cultivars (Seri82 and Scout66) and FHB resistant cultivars (CM82036 and Sumai). Thus, exploitation of these candidate EST-SSRs may help to genotype other wheat sources for Fusarium resistance. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Genetic variation patterns of American chestnut populations at EST-SSRs

    Treesearch

    Oliver Gailing; C. Dana Nelson

    2017-01-01

    The objective of this study is to analyze patterns of genetic variation at genic expressed sequence tag - simple sequence repeats (EST-SSRs) and at chloroplast DNA markers in populations of American chestnut (Castanea dentata Borkh.) to assist in conservation and breeding efforts. Allelic diversity at EST-SSRs decreased significantly from southwest to northeast along...

  1. Exploring root symbiotic programs in the model legume Medicago truncatula using EST analysis.

    PubMed

    Journet, Etienne-Pascal; van Tuinen, Diederik; Gouzy, Jérome; Crespeau, Hervé; Carreau, Véronique; Farmer, Mary-Jo; Niebel, Andreas; Schiex, Thomas; Jaillon, Olivier; Chatagnier, Odile; Godiard, Laurence; Micheli, Fabienne; Kahn, Daniel; Gianinazzi-Pearson, Vivienne; Gamas, Pascal

    2002-12-15

    We report on a large-scale expressed sequence tag (EST) sequencing and analysis program aimed at characterizing the sets of genes expressed in roots of the model legume Medicago truncatula during interactions with either of two microsymbionts, the nitrogen-fixing bacterium Sinorhizobium meliloti or the arbuscular mycorrhizal fungus Glomus intraradices. We have designed specific tools for in silico analysis of EST data, in relation to chimeric cDNA detection, EST clustering, encoded protein prediction, and detection of differential expression. Our 21 473 5'- and 3'-ESTs could be grouped into 6359 EST clusters, corresponding to distinct virtual genes, along with 52 498 other M.truncatula ESTs available in the dbEST (NCBI) database that were recruited in the process. These clusters were manually annotated, using a specifically developed annotation interface. Analysis of EST cluster distribution in various M.truncatula cDNA libraries, supported by a refined R test to evaluate statistical significance and by 'electronic northern' representation, enabled us to identify a large number of novel genes predicted to be up- or down-regulated during either symbiotic root interaction. These in silico analyses provide a first global view of the genetic programs for root symbioses in M.truncatula. A searchable database has been built and can be accessed through a public interface.

  2. Prediction of EST functional relationships via literature mining with user-specified parameters.

    PubMed

    Wang, Hei-Chia; Huang, Tian-Hsiang

    2009-04-01

    The massive amount of expressed sequence tags (ESTs) gathered over recent years has triggered great interest in efficient applications for genomic research. In particular, EST functional relationships can be used to determine a possible gene network for biological processes of interest. In recent years, many researchers have tried to determine EST functional relationships by analyzing the biological literature. However, it has been challenging to find efficient prediction methods. Moreover, an annotated EST is usually associated with many functions, so successful methods must be able to distinguish between relevant and irrelevant functions based on user specifications. This paper proposes a method to discover functional relationships between ESTs of interest by analyzing literature from the Medical Literature Analysis and Retrieval System Online, with user-specified parameters for selecting keywords. This method performs better than the multiple kernel documents method in setting up a specific threshold for gathering materials. The method is also able to uncover known functional relationships, as shown by a comparison with the Kyoto Encyclopedia of Genes and Genomes database. The reliable EST relationships predicted by the proposed method can help to construct gene networks for specific biological functions of interest.

  3. Update of the Diatom EST Database: a new tool for digital transcriptomics

    PubMed Central

    Maheswari, Uma; Mock, Thomas; Armbrust, E. Virginia; Bowler, Chris

    2009-01-01

    The Diatom Expressed Sequence Tag (EST) Database was constructed to provide integral access to ESTs from these ecologically and evolutionarily interesting microalgae. It has now been updated with 130 000 Phaeodactylum tricornutum ESTs from 16 cDNA libraries and 77 000 Thalassiosira pseudonana ESTs from seven libraries, derived from cells grown in different nutrient and stress regimes. The updated relational database incorporates results from statistical analyses such as log-likelihood ratios and hierarchical clustering, which help to identify differentially expressed genes under different conditions, and allow similarities in gene expression in different libraries to be investigated in a functional context. The database also incorporates links to the recently sequenced genomes of P. tricornutum and T. pseudonana, enabling an easy cross-talk between the expression pattern of diatom orthologs and the genome browsers. These improvements will facilitate exploration of diatom responses to conditions of ecological relevance and will aid gene function identification of diatom-specific genes and in silico gene prediction in this largely unexplored class of eukaryotes. The updated Diatom EST Database is available at http://www.biologie.ens.fr/diatomics/EST3. PMID:19029140

  4. The pEst version 2.1 user's manual

    NASA Technical Reports Server (NTRS)

    Murray, James E.; Maine, Richard E.

    1987-01-01

    This report is a user's manual for version 2.1 of pEst, a FORTRAN 77 computer program for interactive parameter estimation in nonlinear dynamic systems. The pEst program allows the user complete generality in definig the nonlinear equations of motion used in the analysis. The equations of motion are specified by a set of FORTRAN subroutines; a set of routines for a general aircraft model is supplied with the program and is described in the report. The report also briefly discusses the scope of the parameter estimation problem the program addresses. The report gives detailed explanations of the purpose and usage of all available program commands and a description of the computational algorithms used in the program.

  5. The Est3 protein associates with yeast telomerase through an OB-fold domain

    PubMed Central

    Lee, Jaesung S.; Mandell, Edward K.; Tucey, Timothy M.; Morris, Danna K.; Victoria, Lundblad

    2009-01-01

    The Est3 protein is a small regulatory subunit of yeast telomerase which is dispensable for enzyme catalysis but essential for telomere replication in vivo. Using structure prediction combined with in vivo characterization, we show here that Est3 consists of a predicted OB (oligo-saccharide/oligo-nucleotide binding) fold. Mutagenesis of predicted surface residues was used to generate a functional map of one surface of Est3, which identified a site that mediates association with the telomerase complex. Surprisingly, the predicted OB-fold of Est3 is structurally similar to the OB-fold of the mammalian TPP1 protein, despite the fact that Est3 and TPP1, as components of telomerase and a telomere capping complex, respectively, perform functionally distinct tasks at chromosome ends. The analysis performed on Est3 may be instructive in generating comparable missense mutations on the surface of the OB-fold domain of TPP1. PMID:19172754

  6. Mater semper incertus est: who's your mummy?

    PubMed

    D'alton-Harrison, Rita

    2014-01-01

    In English law, the legal term for father has been given a broad definition but the definition of mother remains rooted in biology with the Roman law principle mater semper certa est (the mother is always certain) remaining the norm. However, motherhood may be acquired through giving birth to a child, by donation of gametes or by caring and nurturing a child so that the identity of the mother is no longer certain particularly in the case of surrogacy arrangements. While the law in the UK may automatically recognise the parental status of a commissioning father in a traditional surrogacy arrangement, the parental status of the commissioning mother is not automatically recognised in either a traditional or a gestational surrogacy arrangement. Thus the maxim mater est quam gestation demonstrat (meaning the mother is demonstrated by gestation) is also not approached consistently in the legal interpretation of parentage or motherhood in surrogacy as against other assisted reproduction methods. This raises questions about the extent to which motherhood should be affected by the method of reproduction and whether the sociological and philosophical concept of motherhood should, in the case of surrogacy, give rise to a new principle of 'mater semper incertus est' (the mother is uncertain). This article will argue that the time has come to move away from a legal definition of 'mother' that is based on biology to one that recognises the different forms of motherhood. © The Author [2014]. Published by Oxford University Press; all rights reserved. For Permissions, please email: journals.permissions@oup.com.

  7. 9 CFR 307.7 - Safety requirements for electrical stimulating (EST) equipment.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... requirements for electrical stimulating (EST) equipment. (a) General. Electrical stimulating (EST) equipment is... of facilitating blood removal. These provisions do not apply to electrical equipment used to stun and... generate pulsed DC or AC voltage for stimulation and is separate from the equipment used to apply the...

  8. 9 CFR 307.7 - Safety requirements for electrical stimulating (EST) equipment.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... requirements for electrical stimulating (EST) equipment. (a) General. Electrical stimulating (EST) equipment is... of facilitating blood removal. These provisions do not apply to electrical equipment used to stun and... generate pulsed DC or AC voltage for stimulation and is separate from the equipment used to apply the...

  9. EVER-EST: European Virtual Environment for Research in Earth Science Themes

    NASA Astrophysics Data System (ADS)

    Glaves, H.; Albani, M.

    2016-12-01

    EVER-EST is an EC Horizon 2020 project having the goal to develop a Virtual Research Environment (VRE) providing a state-of-the-art solution to allow Earth Scientists to preserve their work and publications for reference and future reuse, and to share with others. The availability of such a solution, based on an innovative concept and state of art technology infrastructure, will considerably enhance the quality of how Earth Scientists work together within their own institution and also across other organizations, regions and countries. The concept of Research Objects (ROs), used in the Earth Sciences for the first time, will form the backbone of the EVER-EST VRE infrastructure. ROs will enhance the ability to preserve, re-use and share entire or individual parts of scientific workflows and all the resources related to a specific scientific investigation. These ROs will also potentially be used as part of the scholarly publication process. EVER-EST is building on technologies developed during almost 15 years of research on Earth Science data management infrastructures. The EVER-EST VRE Service Oriented Architecture is being meticulously designed to accommodate at best the requirements of a wide range of Earth Science communities and use cases: focus is put on common requirements and on minimising the level of complexity in the EVER-EST VRE to ensure future sustainability within the user communities beyond the end of the project. The EVER-EST VRE will be validated through its customisation and deployment by four Virtual Research Communities (VRCs) from different Earth Science disciplines and will support enhanced interaction between data providers and scientists in the Earth Science domain. User community will range from bio-marine researchers (Sea Monitoring use case), to common foreign and security policy institutions and stakeholders (Land Monitoring for Security use case), natural hazards forecasting systems (Natural Hazards use case), and disaster and risk

  10. Generation, annotation and analysis of ESTs from Trichoderma harzianum CECT 2413

    PubMed Central

    Vizcaíno, Juan Antonio; González, Francisco Javier; Suárez, M Belén; Redondo, José; Heinrich, Julian; Delgado-Jarana, Jesús; Hermosa, Rosa; Gutiérrez, Santiago; Monte, Enrique; Llobell, Antonio; Rey, Manuel

    2006-01-01

    Background The filamentous fungus Trichoderma harzianum is used as biological control agent of several plant-pathogenic fungi. In order to study the genome of this fungus, a functional genomics project called "TrichoEST" was developed to give insights into genes involved in biological control activities using an approach based on the generation of expressed sequence tags (ESTs). Results Eight different cDNA libraries from T. harzianum strain CECT 2413 were constructed. Different growth conditions involving mainly different nutrient conditions and/or stresses were used. We here present the analysis of the 8,710 ESTs generated. A total of 3,478 unique sequences were identified of which 81.4% had sequence similarity with GenBank entries, using the BLASTX algorithm. Using the Gene Ontology hierarchy, we performed the annotation of 51.1% of the unique sequences and compared its distribution among the gene libraries. Additionally, the InterProScan algorithm was used in order to further characterize the sequences. The identification of the putatively secreted proteins was also carried out. Later, based on the EST abundance, we examined the highly expressed genes and a hydrophobin was identified as the gene expressed at the highest level. We compared our collection of ESTs with the previous collections obtained from Trichoderma species and we also compared our sequence set with different complete eukaryotic genomes from several animals, plants and fungi. Accordingly, the presence of similar sequences in different kingdoms was also studied. Conclusion This EST collection and its annotation provide a significant resource for basic and applied research on T. harzianum, a fungus with a high biotechnological interest. PMID:16872539

  11. Exploiting a wheat EST database to assess genetic diversity

    PubMed Central

    2010-01-01

    Expressed sequence tag (EST) markers have been used to assess variety and genetic diversity in wheat (Triticum aestivum). In this study, 1549 ESTs from wheat infested with yellow rust were used to examine the genetic diversity of six susceptible and resistant wheat cultivars. The aim of using these cultivars was to improve the competitiveness of public wheat breeding programs through the intensive use of modern, particularly marker-assisted, selection technologies. The F2 individuals derived from cultivar crosses were screened for resistance to yellow rust at the seedling stage in greenhouses and adult stage in the field to identify DNA markers genetically linked to resistance. Five hundred and sixty ESTs were assembled into 136 contigs and 989 singletons. BlastX search results showed that 39 (29%) contigs and 96 (10%) singletons were homologous to wheat genes. The database-matched contigs and singletons were assigned to eight functional groups related to protein synthesis, photosynthesis, metabolism and energy, stress proteins, transporter proteins, protein breakdown and recycling, cell growth and division and reactive oxygen scavengers. PCR analyses with primers based on the contigs and singletons showed that the most polymorphic functional categories were photosynthesis (contigs) and metabolism and energy (singletons). EST analysis revealed considerable genetic variability among the Turkish wheat cultivars resistant and susceptible to yellow rust disease and allowed calculation of the mean genetic distance between cultivars, with the greatest similarity (0.725) being between Harmankaya99 and Sönmez2001, and the lowest (0.622) between Aytin98 and Izgi01. PMID:21637582

  12. Exploiting a wheat EST database to assess genetic diversity.

    PubMed

    Karakas, Ozge; Gurel, Filiz; Uncuoglu, Ahu Altinkut

    2010-10-01

    Expressed sequence tag (EST) markers have been used to assess variety and genetic diversity in wheat (Triticum aestivum). In this study, 1549 ESTs from wheat infested with yellow rust were used to examine the genetic diversity of six susceptible and resistant wheat cultivars. The aim of using these cultivars was to improve the competitiveness of public wheat breeding programs through the intensive use of modern, particularly marker-assisted, selection technologies. The F(2) individuals derived from cultivar crosses were screened for resistance to yellow rust at the seedling stage in greenhouses and adult stage in the field to identify DNA markers genetically linked to resistance. Five hundred and sixty ESTs were assembled into 136 contigs and 989 singletons. BlastX search results showed that 39 (29%) contigs and 96 (10%) singletons were homologous to wheat genes. The database-matched contigs and singletons were assigned to eight functional groups related to protein synthesis, photosynthesis, metabolism and energy, stress proteins, transporter proteins, protein breakdown and recycling, cell growth and division and reactive oxygen scavengers. PCR analyses with primers based on the contigs and singletons showed that the most polymorphic functional categories were photosynthesis (contigs) and metabolism and energy (singletons). EST analysis revealed considerable genetic variability among the Turkish wheat cultivars resistant and susceptible to yellow rust disease and allowed calculation of the mean genetic distance between cultivars, with the greatest similarity (0.725) being between Harmankaya99 and Sönmez2001, and the lowest (0.622) between Aytin98 and Izgi01.

  13. MELOGEN: an EST database for melon functional genomics

    PubMed Central

    Gonzalez-Ibeas, Daniel; Blanca, José; Roig, Cristina; González-To, Mireia; Picó, Belén; Truniger, Verónica; Gómez, Pedro; Deleu, Wim; Caño-Delgado, Ana; Arús, Pere; Nuez, Fernando; Garcia-Mas, Jordi; Puigdomènech, Pere; Aranda, Miguel A

    2007-01-01

    Background Melon (Cucumis melo L.) is one of the most important fleshy fruits for fresh consumption. Despite this, few genomic resources exist for this species. To facilitate the discovery of genes involved in essential traits, such as fruit development, fruit maturation and disease resistance, and to speed up the process of breeding new and better adapted melon varieties, we have produced a large collection of expressed sequence tags (ESTs) from eight normalized cDNA libraries from different tissues in different physiological conditions. Results We determined over 30,000 ESTs that were clustered into 16,637 non-redundant sequences or unigenes, comprising 6,023 tentative consensus sequences (contigs) and 10,614 unclustered sequences (singletons). Many potential molecular markers were identified in the melon dataset: 1,052 potential simple sequence repeats (SSRs) and 356 single nucleotide polymorphisms (SNPs) were found. Sixty-nine percent of the melon unigenes showed a significant similarity with proteins in databases. Functional classification of the unigenes was carried out following the Gene Ontology scheme. In total, 9,402 unigenes were mapped to one or more ontology. Remarkably, the distributions of melon and Arabidopsis unigenes followed similar tendencies, suggesting that the melon dataset is representative of the whole melon transcriptome. Bioinformatic analyses primarily focused on potential precursors of melon micro RNAs (miRNAs) in the melon dataset, but many other genes potentially controlling disease resistance and fruit quality traits were also identified. Patterns of transcript accumulation were characterised by Real-Time-qPCR for 20 of these genes. Conclusion The collection of ESTs characterised here represents a substantial increase on the genetic information available for melon. A database (MELOGEN) which contains all EST sequences, contig images and several tools for analysis and data mining has been created. This set of sequences constitutes

  14. Construction, database integration, and application of an Oenothera EST library.

    PubMed

    Mrácek, Jaroslav; Greiner, Stephan; Cho, Won Kyong; Rauwolf, Uwe; Braun, Martha; Umate, Pavan; Altstätter, Johannes; Stoppel, Rhea; Mlcochová, Lada; Silber, Martina V; Volz, Stefanie M; White, Sarah; Selmeier, Renate; Rudd, Stephen; Herrmann, Reinhold G; Meurer, Jörg

    2006-09-01

    Coevolution of cellular genetic compartments is a fundamental aspect in eukaryotic genome evolution that becomes apparent in serious developmental disturbances after interspecific organelle exchanges. The genus Oenothera represents a unique, at present the only available, resource to study the role of the compartmentalized plant genome in diversification of populations and speciation processes. An integrated approach involving cDNA cloning, EST sequencing, and bioinformatic data mining was chosen using Oenothera elata with the genetic constitution nuclear genome AA with plastome type I. The Gene Ontology system grouped 1621 unique gene products into 17 different functional categories. Application of arrays generated from a selected fraction of ESTs revealed significantly differing expression profiles among closely related Oenothera species possessing the potential to generate fertile and incompatible plastid/nuclear hybrids (hybrid bleaching). Furthermore, the EST library provides a valuable source of PCR-based polymorphic molecular markers that are instrumental for genotyping and molecular mapping approaches.

  15. ESTuber db: an online database for Tuber borchii EST sequences.

    PubMed

    Lazzari, Barbara; Caprera, Andrea; Cosentino, Cristian; Stella, Alessandra; Milanesi, Luciano; Viotti, Angelo

    2007-03-08

    The ESTuber database (http://www.itb.cnr.it/estuber) includes 3,271 Tuber borchii expressed sequence tags (EST). The dataset consists of 2,389 sequences from an in-house prepared cDNA library from truffle vegetative hyphae, and 882 sequences downloaded from GenBank and representing four libraries from white truffle mycelia and ascocarps at different developmental stages. An automated pipeline was prepared to process EST sequences using public software integrated by in-house developed Perl scripts. Data were collected in a MySQL database, which can be queried via a php-based web interface. Sequences included in the ESTuber db were clustered and annotated against three databases: the GenBank nr database, the UniProtKB database and a third in-house prepared database of fungi genomic sequences. An algorithm was implemented to infer statistical classification among Gene Ontology categories from the ontology occurrences deduced from the annotation procedure against the UniProtKB database. Ontologies were also deduced from the annotation of more than 130,000 EST sequences from five filamentous fungi, for intra-species comparison purposes. Further analyses were performed on the ESTuber db dataset, including tandem repeats search and comparison of the putative protein dataset inferred from the EST sequences to the PROSITE database for protein patterns identification. All the analyses were performed both on the complete sequence dataset and on the contig consensus sequences generated by the EST assembly procedure. The resulting web site is a resource of data and links related to truffle expressed genes. The Sequence Report and Contig Report pages are the web interface core structures which, together with the Text search utility and the Blast utility, allow easy access to the data stored in the database.

  16. Comparative mapping in the Fagaceae and beyond with EST-SSRs

    PubMed Central

    2012-01-01

    Background Genetic markers and linkage mapping are basic prerequisites for comparative genetic analyses, QTL detection and map-based cloning. A large number of mapping populations have been developed for oak, but few gene-based markers are available for constructing integrated genetic linkage maps and comparing gene order and QTL location across related species. Results We developed a set of 573 expressed sequence tag-derived simple sequence repeats (EST-SSRs) and located 397 markers (EST-SSRs and genomic SSRs) on the 12 oak chromosomes (2n = 2x = 24) on the basis of Mendelian segregation patterns in 5 full-sib mapping pedigrees of two species: Quercus robur (pedunculate oak) and Quercus petraea (sessile oak). Consensus maps for the two species were constructed and aligned. They showed a high degree of macrosynteny between these two sympatric European oaks. We assessed the transferability of EST-SSRs to other Fagaceae genera and a subset of these markers was mapped in Castanea sativa, the European chestnut. Reasonably high levels of macrosynteny were observed between oak and chestnut. We also obtained diversity statistics for a subset of EST-SSRs, to support further population genetic analyses with gene-based markers. Finally, based on the orthologous relationships between the oak, Arabidopsis, grape, poplar, Medicago, and soybean genomes and the paralogous relationships between the 12 oak chromosomes, we propose an evolutionary scenario of the 12 oak chromosomes from the eudicot ancestral karyotype. Conclusions This study provides map locations for a large set of EST-SSRs in two oak species of recognized biological importance in natural ecosystems. This first step toward the construction of a gene-based linkage map will facilitate the assignment of future genome scaffolds to pseudo-chromosomes. This study also provides an indication of the potential utility of new gene-based markers for population genetics and comparative mapping within and beyond the

  17. New Currents in Education: A Preliminary Review. QuEST Paper 10.

    ERIC Educational Resources Information Center

    Bhaerman, Robert D.

    This booklet describes nine "new currents" in education with the recommendation that local and state federations of the American Federation of Teachers create QuEST committees of teachers to study the implications of all these issues and develop statements and QuEST action programs on them as they relate to local and state situations. The issues…

  18. The interaction between the yeast telomerase RNA and the Est1 protein requires three structural elements.

    PubMed

    Lubin, Johnathan W; Tucey, Timothy M; Lundblad, Victoria

    2012-09-01

    In the budding yeast Saccharomyces cerevisiae, the telomerase enzyme is composed of a 1.3-kb TLC1 RNA that forms a complex with Est2 (the catalytic subunit) and two regulatory proteins, Est1 and Est3. Previous work has identified a conserved 5-nt bulge, present in a long helical arm of TLC1, which mediates binding of Est1 to TLC1. However, increased expression of Est1 can bypass the consequences of removal of this RNA bulge, indicating that there are additional binding site(s) for Est1 on TLC1. We report here that a conserved single-stranded internal loop immediately adjacent to the bulge is also required for the Est1-RNA interaction; furthermore, a TLC1 variant that lacks this internal loop but retains the bulge cannot be suppressed by Est1 overexpression, arguing that the internal loop may be a more critical element for Est1 binding. An additional structural feature consisting of a single-stranded region at the base of the helix containing the bulge and internal loop also contributes to recognition of TLC1 by Est1, potentially by providing flexibility to this helical arm. Association of Est1 with each of these TLC1 motifs was assessed using a highly sensitive biochemical assay that simultaneously monitors the relative levels of the Est1 and Est2 proteins in the telomerase complex. The identification of three elements of TLC1 that are required for Est1 association provides a detailed view of this particular protein-RNA interaction.

  19. Smoking status is inversely associated with overall diet quality: Findings from the ORISCAV-LUX study.

    PubMed

    Alkerwi, Ala'a; Baydarlioglu, Burcu; Sauvageot, Nicolas; Stranges, Saverio; Lemmens, Paul; Shivappa, Nitin; Hébert, James R

    2017-10-01

    Relationships between food consumption/nutrient intake and tobacco smoking have been described in the literature. However, little is known about the association between smoking and overall diet quality. This study examined the associations between eight diet quality indices, namely, the Diet Quality Index-International (DQI-I), Recommendation Compliance Index (RCI), Dietary Approach to Stop Hypertension (DASH) score, Energy Density Score (EDS), Dietary Diversity Score (DDS), Recommended Food Score (RFS), non-Recommended Food Score (non-RFS), and Dietary Inflammatory Index (DII), and smoking status with a focus on smoking intensity. Analyses were based on a sample of 1352 participants in the Observation of Cardiovascular Risk Factors in Luxembourg (ORISCAV-LUX) survey, a nationwide population-based cross-sectional study of adults aged 18-69 years. Nutritional data from food frequency questionnaire (FFQ) were used to compute selected diet quality indices. Participants were classified as never smoker, former smoker (≥12 months cessation period), occasional or light smokers (≤1 cig/d), moderate smokers (≤20 cig/d) and heavy smokers (>20 cig/d). Descriptive and linear regression analyses were performed, after adjustment for several potential covariates. Compared to the other groups, heavy smokers had significantly higher prevalence of dyslipidemia (83%), obesity (34%), and elevated glycemic biomarkers. About 50% of former smokers had hypertension. Diet quality of heavy smokers was significantly poorer than those who never smoked independent of several socioeconomic, lifestyle, and biologic confounding factors (all p < 0.001). Heavy smokers were less compliant with national or international dietary recommendations, expressed by RCI, DQI-I, and RFS. In addition, they consumed a more pro-inflammatory diet, as expressed by higher DII scores (P < 0.001) and self-reported less dietary diversity in their food choices, as expressed by DDS. This study provides new

  20. Factors Influencing Worker Morale: Evaluating Provider Demographics, Workplace Environment and Using ESTs

    ERIC Educational Resources Information Center

    Patterson-Silver Wolf, David A.; Dulmus, Catherine N.; Maguin, Eugene; Cristalli, Maria

    2013-01-01

    Objectives: Mental health organizations are strongly encouraged to implement empirically supported treatments (ESTs); however, little is known about their working environments. The present study investigated how provider demographics, workplace environment, and whether ESTs were used affected the worker morale. Method: Frontline workers…

  1. Hierarchical Control on Polyene Macrolide Biosynthesis: PimR Modulates Pimaricin Production via the PAS-LuxR Transcriptional Activator PimM

    PubMed Central

    Santos-Aberturas, Javier; Vicente, Cláudia M.; Payero, Tamara D.; Martín-Sánchez, Lara; Cañibano, Carmen; Martín, Juan F.; Aparicio, Jesús F.

    2012-01-01

    Control of polyene macrolide production in Streptomyces natalensis is mediated by the transcriptional activator PimR. This regulator combines an N-terminal domain corresponding to the Streptomyces antibiotic regulatory protein (SARP) family of transcriptional activators with a C-terminal half homologous to guanylate cyclases and large ATP-binding regulators of the LuxR family. The PimR SARP domain (PimRSARP) was expressed in Escherichia coli as a glutathione S-transferase (GST)–fused protein. Electrophoretic mobility shift assays showed that GST-PimRSARP binds a single target, the intergenic region between the regulatory genes pimR and pimMs in the pimaricin cluster. The PimRSARP-binding site was investigated by DNaseI protection studies, revealing that it contains three heptameric direct repeats adjusting to the consensus 5′-CGGCAAG-3′. Transcription start points of pimM and pimR promoters were identified by 5′-RACE, revealing that unlike other SARPs, PimRSARP does not interact with the -35 region of its target promoter. Quantitative transcriptional analysis of these regulatory genes on mutants on each of them has allowed the identification of the pimM promoter as the transcriptional target for PimR. Furthermore, the constitutive expression of pimM restored pimaricin production in a pimaricin-deficient strain carrying a deletion mutant of pimR. These results reveal that PimR exerts its positive effect on pimaricin production by controlling pimM expression level, a regulator whose gene product activates transcription from eight different promoters of pimaricin structural genes directly. PMID:22693644

  2. A Small-Scale 3D Imaging Platform for Algorithm Performance Evaluation

    DTIC Science & Technology

    2007-06-01

    between their acquisitions will form the basis for stereo analysis , and thus a 3D perception of the observed scene. Several low cost and economic...incident light versus 2% on a photographic type film [6]. The CCD camera then transforms these patterns of light into electrical signals. First...sources of lux or illumination. Table 1: Lux (Illumination) Quantitative Comparisons. Luminance Example 0.00005 lux Starlight 1 lux Moonlight 10

  3. SolEST database: a "one-stop shop" approach to the study of Solanaceae transcriptomes.

    PubMed

    D'Agostino, Nunzio; Traini, Alessandra; Frusciante, Luigi; Chiusano, Maria Luisa

    2009-11-30

    Since no genome sequences of solanaceous plants have yet been completed, expressed sequence tag (EST) collections represent a reliable tool for broad sampling of Solanaceae transcriptomes, an attractive route for understanding Solanaceae genome functionality and a powerful reference for the structural annotation of emerging Solanaceae genome sequences. We describe the SolEST database http://biosrv.cab.unina.it/solestdb which integrates different EST datasets from both cultivated and wild Solanaceae species and from two species of the genus Coffea. Background as well as processed data contained in the database, extensively linked to external related resources, represent an invaluable source of information for these plant families. Two novel features differentiate SolEST from other resources: i) the option of accessing and then visualizing Solanaceae EST/TC alignments along the emerging tomato and potato genome sequences; ii) the opportunity to compare different Solanaceae assemblies generated by diverse research groups in the attempt to address a common complaint in the SOL community. Different databases have been established worldwide for collecting Solanaceae ESTs and are related in concept, content and utility to the one presented herein. However, the SolEST database has several distinguishing features that make it appealing for the research community and facilitates a "one-stop shop" for the study of Solanaceae transcriptomes.

  4. The Use of EST Expression Matrixes for the Quality Control of Gene Expression Data

    PubMed Central

    Milnthorpe, Andrew T.; Soloviev, Mikhail

    2012-01-01

    EST expression profiling provides an attractive tool for studying differential gene expression, but cDNA libraries' origins and EST data quality are not always known or reported. Libraries may originate from pooled or mixed tissues; EST clustering, EST counts, library annotations and analysis algorithms may contain errors. Traditional data analysis methods, including research into tissue-specific gene expression, assume EST counts to be correct and libraries to be correctly annotated, which is not always the case. Therefore, a method capable of assessing the quality of expression data based on that data alone would be invaluable for assessing the quality of EST data and determining their suitability for mRNA expression analysis. Here we report an approach to the selection of a small generic subset of 244 UniGene clusters suitable for identification of the tissue of origin for EST libraries and quality control of the expression data using EST expression information alone. We created a small expression matrix of UniGene IDs using two rounds of selection followed by two rounds of optimisation. Our selection procedures differ from traditional approaches to finding “tissue-specific” genes and our matrix yields consistency high positive correlation values for libraries with confirmed tissues of origin and can be applied for tissue typing and quality control of libraries as small as just a few hundred total ESTs. Furthermore, we can pick up tissue correlations between related tissues e.g. brain and peripheral nervous tissue, heart and muscle tissues and identify tissue origins for a few libraries of uncharacterised tissue identity. It was possible to confirm tissue identity for some libraries which have been derived from cancer tissues or have been normalised. Tissue matching is affected strongly by cancer progression or library normalisation and our approach may potentially be applied for elucidating the stage of normalisation in normalised libraries or for cancer

  5. Direct enantioseparation of nitrogen-heterocyclic pesticides on cellulose-based chiral column by high-performance liquid chromatography.

    PubMed

    Chai, Tingting; Yang, Wenwen; Qiu, Jing; Hou, Shicong

    2015-01-01

    The enantiomeric separation of eight pesticides including bitertanol (), diclobutrazol (), fenbuconazole (), triticonazole (), imazalil (), triapenthenol (), ancymidol (), and carfentrazone-ethyl () was achieved, using normal-phase high-performance liquid chromatography on two cellulosed-based chiral columns. The effects of isopropanol composition from 2% to 30% in the mobile phase and column temperature from 5 to 40 °C were investigated. Satisfactory resolutions were obtained for bitertanol (), triticonazole (), imazalil () with the (+)-enantiomer eluted first and fenbuconazole () with the (-)-enantiomer eluted first on Lux Cellulose-2 and Lux Cellulose-3. (+)-Enantiomers of diclobutrazol () and triapenthenol () were first eluted on Lux Cellulose-2. (-)-Carfentrazone-ethyl () were eluted first on Lux Cellulose-2 and Lux Cellulose-3 with incomplete separation. Reversed elution orders were obtained for ancymidol (7). (+)-Ancymidol was first eluted on Lux Cellulose-2 while on Lux Cellulose-3 (-)-ancymidol was first eluted. The results of the elution order at different column temperatures suggested that column temperature did not affect the optical signals of the enantiomers. These results will be helpful to prepare and analyze individual enantiomers of chiral pesticides. © 2014 Wiley Periodicals, Inc.

  6. Experimental High Energy Physics Research: Direct Detection of Dark Matter

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Witherell, Michael S.

    2014-10-02

    The grant supported research on an experimental search for evidence of dark matter interactions with normal matter. The PI carried out the research as a member of the LUX and LZ collaborations. The LUX research team collected a first data set with the LUX experiment, a large liquid xenon detector installed in the Sanford Underground Research Facility (SURF). The first results were published in Physical Review Letters on March 4, 2014. The journal Nature named the LUX result a scientific highlight of the year for 2013. In addition, the LZ collaboration submitted the full proposal for the Lux Zeplin experiment,more » which has since been approved by DOE-HEP as a second-generation dark matter experiment. Witherell is the Level 2 manager for the Outer Detector System on the LUX-Zeplin experiment.« less

  7. ASFinder: a tool for genome-wide identification of alternatively splicing transcripts from EST-derived sequences.

    PubMed

    Min, Xiang Jia

    2013-01-01

    Expressed Sequence Tags (ESTs) are a rich resource for identifying Alternatively Splicing (AS) genes. The ASFinder webserver is designed to identify AS isoforms from EST-derived sequences. Two approaches are implemented in ASFinder. If no genomic sequences are provided, the server performs a local BLASTN to identify AS isoforms from ESTs having both ends aligned but an internal segment unaligned. Otherwise, ASFinder uses SIM4 to map ESTs to the genome, then the overlapping ESTs that are mapped to the same genomic locus and have internal variable exon/intron boundaries are identified as AS isoforms. The tool is available at http://proteomics.ysu.edu/tools/ASFinder.html.

  8. A proposed OB-fold with a protein-interaction surface in Candida albicans telomerase protein Est3

    PubMed Central

    Yu, Eun Young; Wang, Feng; Lei, Ming; Lue, Neal F

    2008-01-01

    Ever shorter telomeres 3 (Est3) is an essential telomerase regulatory subunit thought to be unique to budding yeasts. Here we use multiple sequence alignment and hidden Markov model–hidden Markov model (HMM-HMM) comparison to uncover potential similarities between Est3 and the mammalian telomeric protein Tpp1. Analysis of site-specific mutants of Candida albicans Est3 revealed functional distinctions between residues that are conserved between Est3 and Tpp1 and those that are unique to Est3. Although both types of residues are important for telomere maintenance in vivo, only the former contributes to telomerase activity in vitro and facilitates the association of Est3 with telomerase core components. Consistent with a function in protein-protein interaction, the residues common to Est3 and Tpp1 map to one face of an OB-fold model structure, away from the canonical nucleic acid binding surface. We propose that Est3 and the OB-fold domain of Tpp1 mediate a conserved function in telomerase regulation. PMID:19172753

  9. Association between nutritional awareness and diet quality: evidence from the observation of cardiovascular risk factors in Luxembourg (ORISCAV-LUX) study.

    PubMed

    Alkerwi, Ala'a; Sauvageot, Nicolas; Malan, Leoné; Shivappa, Nitin; Hébert, James R

    2015-04-14

    This study examined the association between nutritional awareness and diet quality, as indicated by energy density, dietary diversity and adequacy to achieve dietary recommendations, while considering the potentially important role of socioeconomic status (SES). Data were derived from 1351 subjects, aged 18-69 years and enrolled in the ORISCAV-LUX study. Energy density score (EDS), dietary diversity score (DDS) and Recommendation Compliance Index (RCI) were calculated based on data derived from a food frequency questionnaire. Nutritional awareness was defined as self-perception of the importance assigned to eating balanced meals, and classified as high, moderate, or of little importance. Initially, a General Linear Model was fit that adjusted for age, sex, country of birth, and body mass index (BMI). Furthermore, simultaneous contributions to diet quality of individual-level socioeconomic factors, education, and household income were examined across levels of nutritional awareness. Attributing high importance was associated inversely with energy density (p = 0.02), positively with both dietary diversity (p < 0.0001), and adequacy to dietary recommendations (p < 0.0001), independent of demographic factors, weight status and SES. Further adjustment for household income in the EDS-related multivariable model, reduced the β coefficient by 47% for the "moderate importance" category and 36% for the "high importance" category. Likewise, the β coefficient decreased by 13.6% and 10.7% in the DDS-related model, and by 12.5%, and 7.1% in the RCI-related model, respectively, across awareness categories. Nutritional awareness has a direct effect on diet quality, with a minor component of variance explained by improved income. The impact of nutritional awareness on diet quality seems to be a promising area for both health promotion and health policy research.

  10. Crystal Structure and Functional Characterization of an Esterase (EaEST) from Exiguobacterium antarcticum.

    PubMed

    Lee, Chang Woo; Kwon, Sena; Park, Sun-Ha; Kim, Boo-Young; Yoo, Wanki; Ryu, Bum Han; Kim, Han-Woo; Shin, Seung Chul; Kim, Sunghwan; Park, Hyun; Kim, T Doohun; Lee, Jun Hyuck

    2017-01-01

    A novel microbial esterase, EaEST, from a psychrophilic bacterium Exiguobacterium antarcticum B7, was identified and characterized. To our knowledge, this is the first report describing structural analysis and biochemical characterization of an esterase isolated from the genus Exiguobacterium. Crystal structure of EaEST, determined at a resolution of 1.9 Å, showed that the enzyme has a canonical α/β hydrolase fold with an α-helical cap domain and a catalytic triad consisting of Ser96, Asp220, and His248. Interestingly, the active site of the structure of EaEST is occupied by a peracetate molecule, which is the product of perhydrolysis of acetate. This result suggests that EaEST may have perhydrolase activity. The activity assay showed that EaEST has significant perhydrolase and esterase activity with respect to short-chain p-nitrophenyl esters (≤C8), naphthyl derivatives, phenyl acetate, and glyceryl tributyrate. However, the S96A single mutant had low esterase and perhydrolase activity. Moreover, the L27A mutant showed low levels of protein expression and solubility as well as preference for different substrates. On conducting an enantioselectivity analysis using R- and S-methyl-3-hydroxy-2-methylpropionate, a preference for R-enantiomers was observed. Surprisingly, immobilized EaEST was found to not only retain 200% of its initial activity after incubation for 1 h at 80°C, but also retained more than 60% of its initial activity after 20 cycles of reutilization. This research will serve as basis for future engineering of this esterase for biotechnological and industrial applications.

  11. Ligand-Induced Asymmetry in Histidine Sensor Kinase Complex Regulates Quorum Sensing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Neiditch,M.; Federle, M.; Pompeani, A.

    2006-01-01

    Bacteria sense their environment using receptors of the histidine sensor kinase family, but how kinase activity is regulated by ligand binding is not well understood. Autoinducer-2 (AI-2), a secreted signaling molecule originally identified in studies of the marine bacterium Vibrio harveyi, regulates quorum-sensing responses and allows communication between different bacterial species. AI-2 signal transduction in V. harveyi requires the integral membrane receptor LuxPQ, comprised of periplasmic binding protein (LuxP) and histidine sensor kinase (LuxQ) subunits. Combined X-ray crystallographic and functional studies show that AI-2 binding causes a major conformational change within LuxP, which in turn stabilizes a quaternary arrangement inmore » which two LuxPQ monomers are asymmetrically associated. We propose that formation of this asymmetric quaternary structure is responsible for repressing the kinase activity of both LuxQ subunits and triggering the transition of V. harveyi into quorum-sensing mode.« less

  12. Fiat lux!

    PubMed Central

    Renault, Hugues

    2013-01-01

    The non-protein amino acid γ-aminobutyric acid (GABA) accumulates in plants in response to a wide variety of environmental cues. Recent data point toward an involvement of GABA in tricarboxylic acid (TCA) cycle activity and respiration, especially in stressed roots. To gain further insights into potential GABA functions in plants, phylogenetic and bioinformatic approaches were undertaken. Phylogenetic reconstruction of the GABA transaminase (GABA-T) protein family revealed the monophyletic nature of plant GABA-Ts. However, this analysis also pointed to the common origin of several plant aminotransferases families, which were found more similar to plant GABA-Ts than yeast and human GABA-Ts. A computational analysis of AtGABA-T co-expressed genes was performed in roots and in stress conditions. This second approach uncovered a strong connection between GABA metabolism and glyoxylate cycle during stress. Both in silico analyses open new perspectives and hypotheses for GABA metabolic functions in plants. PMID:23518583

  13. Evaluation of the VeriStrat® serum protein test in patients with advanced squamous cell carcinoma of the lung treated with second-line afatinib or erlotinib in the phase III LUX-Lung 8 study.

    PubMed

    Gadgeel, Shirish; Goss, Glenwood; Soria, Jean-Charles; Felip, Enriqueta; Georgoulias, Vassilis; Lu, Shun; Cobo, Manuel; Syrigos, Konstantinos; Lee, Ki Hyeong; Göker, Erdem; Guclu, Salih Z; Isla, Dolores; Morabito, Alessandro; Dupuis, Nicholas; Bühnemann, Claudia; Krämer, Nicole; Solca, Flavio; Ehrnrooth, Eva; Ardizzoni, Andrea

    2017-07-01

    Identification of biomarkers associated with clinical benefit may be crucial in establishing optimal treatment choice for patients with squamous cell carcinoma (SCC) of the lung after first-line chemotherapy. In this study, the ability of the VeriStrat serum protein test to predict differential clinical benefit with afatinib versus erlotinib, and the association of VeriStrat status with clinical outcomes irrespective of EGFR-TKI used, was assessed in a retrospective analysis of the phase III LUX-Lung 8 trial. Pretreatment plasma samples were analyzed using matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Spectra were evaluated to assign a VeriStrat 'Good' (VS-G) or VeriStrat 'Poor' (VS-P) classification. Overall survival (OS), progression-free survival, and other endpoints were assessed with respect to pretreatment VeriStrat status; OS was the primary efficacy variable. Outcomes with other efficacy endpoints were similar. Of 795 patients randomized in LUX-Lung 8, 675 were classified (VS-G: 412; VS-P: 263). In the VS-G group, OS was significantly longer with afatinib versus erlotinib (HR 0.79 [95% CI: 0.63-0.98]). In the VS-P group, there was no significant difference in OS between afatinib and erlotinib (HR 0.90 [0.70-1.16]). However, there was no interaction between VeriStrat classification and treatment group for OS (p interaction =0.5303). OS was significantly longer in VS-G versus VS-P patients, both in the overall VeriStrat-classified population (HR 0.41 [0.35-0.49]) and afatinib-treated patients (HR 0.40 [0.31-0.51]). Multivariate analysis showed that VeriStrat was an independent predictor of OS in afatinib-treated patients, regardless of ECOG PS or best response to first-line chemotherapy. VS-G classification is strongly associated with favorable survival outcomes with either afatinib or erlotinib compared with VS-P classification. In VS-G patients, survival outcomes with afatinib are superior to those with erlotinib. Veri

  14. Trends in improving the embryonic stem cell test (EST): an overview.

    PubMed

    Buesen, Roland; Visan, Anke; Genschow, Elke; Slawik, Birgitta; Spielmann, Horst; Seiler, Andrea

    2004-01-01

    The embryonic stem cell test (EST) is an in vitro assay that has been developed to assess the teratogenic and embryotoxic potential of drugs and chemicals. It is based on the capacity of murine ES cells (cell line D3) to differentiate into contracting myocardial cells under specific cell culture conditions. The appearance of beating cardiomyocytes in embryoid body (EB) outgrowths is used as a toxicological endpoint to assess the embryotoxic potential of a test substance. Applying linear analysis of discriminance, a biostatistical prediction model (PM) was developed to assign test chemicals to three classes of embryotoxicity. In an international validation study the EST predicted the embryotoxic potential of chemicals and drugs with the same reliability as two other in vitro embryotoxicity tests, which employed embryonic cells and tissues from pregnant animals. In a joint research project with German pharmaceutical companies we have successfully improved the EST by establishing molecular endpoints of differentiation in cultured ES cells. The quantification of cardiac-specific protein expression by intracellular flow cytometry has been studied in the presence of chemicals of different embryotoxic potential. The results obtained using molecular endpoints specific for differentiated cardiomyocytes employing FACS (fluorescence-activated cell sorting) analysis will be presented in comparison to the validated endpoint - the microscopic analysis of beating areas. FACS analysis provides a more objective endpoint for predicting the embryotoxic potential of chemicals than the validated method. Furthermore, flow cytometry promises to be suitable for high-throughput screening systems (HTS). In addition, our partners from the joint project have improved the EST by developing protocols that stimulate differentiation of ES cells into neural and endothelial cells, chondrocytes and osteoblasts, because some substances might have embryotoxic effects on specific cell-types other than

  15. Autoinducer-2 Plays a Crucial Role in Gut Colonization and Probiotic Functionality of Bifidobacterium breve UCC2003

    PubMed Central

    Bottacini, Francesca; Lanigan, Noreen; Casey, Pat G.; Huys, Geert; Nelis, Hans J.; van Sinderen, Douwe; Coenye, Tom

    2014-01-01

    In the present study we show that luxS of Bifidobacterium breve UCC2003 is involved in the production of the interspecies signaling molecule autoinducer-2 (AI-2), and that this gene is essential for gastrointestinal colonization of a murine host, while it is also involved in providing protection against Salmonella infection in Caenorhabditis elegans. We demonstrate that a B. breve luxS-insertion mutant is significantly more susceptible to iron chelators than the WT strain and that this sensitivity can be partially reverted in the presence of the AI-2 precursor DPD. Furthermore, we show that several genes of an iron starvation-induced gene cluster, which are downregulated in the luxS-insertion mutant and which encodes a presumed iron-uptake system, are transcriptionally upregulated under in vivo conditions. Mutation of two genes of this cluster in B. breve UCC2003 renders the derived mutant strains sensitive to iron chelators while deficient in their ability to confer gut pathogen protection to Salmonella-infected nematodes. Since a functional luxS gene is present in all tested members of the genus Bifidobacterium, we conclude that bifidobacteria operate a LuxS-mediated system for gut colonization and pathogen protection that is correlated with iron acquisition. PMID:24871429

  16. Autoinducer-2 plays a crucial role in gut colonization and probiotic functionality of Bifidobacterium breve UCC2003.

    PubMed

    Christiaen, Steven E A; O'Connell Motherway, Mary; Bottacini, Francesca; Lanigan, Noreen; Casey, Pat G; Huys, Geert; Nelis, Hans J; van Sinderen, Douwe; Coenye, Tom

    2014-01-01

    In the present study we show that luxS of Bifidobacterium breve UCC2003 is involved in the production of the interspecies signaling molecule autoinducer-2 (AI-2), and that this gene is essential for gastrointestinal colonization of a murine host, while it is also involved in providing protection against Salmonella infection in Caenorhabditis elegans. We demonstrate that a B. breve luxS-insertion mutant is significantly more susceptible to iron chelators than the WT strain and that this sensitivity can be partially reverted in the presence of the AI-2 precursor DPD. Furthermore, we show that several genes of an iron starvation-induced gene cluster, which are downregulated in the luxS-insertion mutant and which encodes a presumed iron-uptake system, are transcriptionally upregulated under in vivo conditions. Mutation of two genes of this cluster in B. breve UCC2003 renders the derived mutant strains sensitive to iron chelators while deficient in their ability to confer gut pathogen protection to Salmonella-infected nematodes. Since a functional luxS gene is present in all tested members of the genus Bifidobacterium, we conclude that bifidobacteria operate a LuxS-mediated system for gut colonization and pathogen protection that is correlated with iron acquisition.

  17. Physical and functional maps of the luminescence gene cluster in an autoinducer-deficient Vibrio fischeri strain isolated from a squid light organ.

    PubMed

    Gray, K M; Greenberg, E P

    1992-07-01

    Vibrio fischeri ES114 is an isolate representing the specific bacterial light organ symbiont of the squid Euprymna scolopes. An interesting feature of this strain of V. fischeri is that it is visibly luminous within the light organ of the squid host but is nonluminous when grown under standard laboratory conditions. Luminescence can be restored in laboratory culture, however, by the addition of autoinducer, a species-specific inducer of the V. fischeri luminescence (lux) genes. Most other isolates of V. fischeri produce autoinducer in sufficient quantities to induce luminescence in laboratory culture. We have cloned an 8.8-kb DNA fragment from V. fischeri ES114 that encodes all of the functions necessary for luminescence in Escherichia coli in the absence of exogenous autoinducer. This DNA contains both of the recognized V. fischeri lux regulatory genes, one of which (luxI) directs E. coli to synthesize autoinducer. The organization of the individual lux genes within this DNA fragment appears to be the same as that in the other strains of V. fischeri studied; the restriction map of the V. fischeri ES114 lux DNA has diverged substantially, however, from the largely conserved maps of V. fischeri MJ1 and ATCC 7744. Although E. coli containing the V. fischeri ES114 lux DNA synthesizes considerable amounts of autoinducer, V. fischeri ES114 synthesizes autoinducer only in small amounts, even when transcription of the lux genes, including luxI, is activated by the addition of exogenous autoinducer. Nonetheless, transconjugants of V. fischeri ES114 that contain multicopy plasmids bearing the ES114 lux genes synthesize sufficient autoinducer to induce luminescence. These results suggest that V. fischeri ES11r does not lack a functional luxl, nor is it deficient in the ability to synthesize metabolic precursors for autoinducer synthesis.

  18. Mechanism for iron control of the Vibrio fischeri luminescence system: involvement of cyclic AMP and cyclic AMP receptor protein and modulation of DNA level.

    PubMed

    Dunlap, P V

    1992-07-01

    Iron controls luminescence in Vibrio fischeri by an indirect but undefined mechanism. To gain insight into that mechanism, the involvement of cyclic AMP (cAMP) and cAMP receptor protein (CRP) and of modulation of DNA levels in iron control of luminescence were examined in V. fischeri and in Escherichia coli containing the cloned V. fischeri lux genes on plasmids. For V. fischeri and E. coli adenylate cyclase (cya) and CRP (crp) mutants containing intact lux genes (luxR luxICDABEG), presence of the iron chelator ethylenediamine-di(o-hydroxyphenyl acetic acid) (EDDHA) increased expression of the luminescence system like in the parent strains only in the cya mutants in the presence of added cAMP. In the E. coli strains containing a plasmid with a Mu dl(lacZ) fusion in luxR, levels of beta-galactosidase activity (expression from the luxR promoter) and luciferase activity (expression from the lux operon promoter) were both 2-3-fold higher in the presence of EDDHA in the parent strain, and for the mutants this response to EDDHA was observed only in the cya mutant in the presence of added cAMP. Therefore, cAMP and CRP are required for the iron restriction effect on luminescence, and their involvement in iron control apparently is distinct from the known differential control of transcription from the luxR and luxICDABEG promoters by cAMP-CRP. Furthermore, plasmid and chromosomal DNA levels were higher in E. coli and V. fischeri in the presence of EDDHA. The higher DNA levels correlated with an increase in expression of chromosomally encoded beta-galactosidase in E. coli and with a higher level of autoinducer in cultures of V. fischeri. These results implicate cAMP-CRP and modulation of DNA levels in the mechanism of iron control of the V. fischeri luminescence system.

  19. Molecular Docking, Molecular Dynamics Simulations, Computational Screening to Design Quorum Sensing Inhibitors Targeting LuxP of Vibrio harveyi and Its Biological Evaluation.

    PubMed

    Rajamanikandan, Sundaraj; Jeyakanthan, Jeyaraman; Srinivasan, Pappu

    2017-01-01

    Quorum sensing (QS) plays an important role in the biofilm formation, production of virulence factors and stress responses in Vibrio harveyi. Therefore, interrupting QS is a possible approach to modulate bacterial behavior. In the present study, three docking protocols, such as Rigid Receptor Docking (RRD), Induced Fit Docking (IFD), and Quantum Polarized Ligand Docking (QPLD) were used to elucidate the binding mode of boronic acid derivatives into the binding pocket of LuxP protein in V. harveyi. Among the three docking protocols, IFD accurately predicted the correct binding mode of the studied inhibitors. Molecular dynamics (MD) simulations of the protein-ligand complexes indicates that the inter-molecular hydrogen bonds formed between the protein and ligand complex remains stable during the simulation time. Pharmacophore and shape-based virtual screening were performed to find selective and potent compounds from ChemBridge database. Five hit compounds were selected and subjected to IFD and MD simulations to validate the binding mode. In addition, enrichment calculation was performed to discriminate and separate active compounds from the inactive compounds. Based on the computational studies, the potent Bicyclo [2.2.1] hept-5-ene-2,3-dicarboxylic acid-2,6-dimethylpyridine 1-oxide (ChemBridge_5144368) was selected for in vitro assays. The compound exhibited dose dependent inhibition in bioluminescence and also inhibits biofilm formation in V. harveyi to the level of 64.25 %. The result from the study suggests that ChemBridge_5144368 could serve as an anti-quorum sensing molecule for V. harveyi.

  20. Needles in the EST Haystack: Large-Scale Identification and Analysis of Excretory-Secretory (ES) Proteins in Parasitic Nematodes Using Expressed Sequence Tags (ESTs)

    PubMed Central

    Nagaraj, Shivashankar H.; Gasser, Robin B.; Ranganathan, Shoba

    2008-01-01

    Background Parasitic nematodes of humans, other animals and plants continue to impose a significant public health and economic burden worldwide, due to the diseases they cause. Promising antiparasitic drug and vaccine candidates have been discovered from excreted or secreted (ES) proteins released from the parasite and exposed to the immune system of the host. Mining the entire expressed sequence tag (EST) data available from parasitic nematodes represents an approach to discover such ES targets. Methods and Findings In this study, we predicted, using EST2Secretome, a novel, high-throughput, computational workflow system, 4,710 ES proteins from 452,134 ESTs derived from 39 different species of nematodes, parasitic in animals (including humans) or plants. In total, 2,632, 786, and 1,292 ES proteins were predicted for animal-, human-, and plant-parasitic nematodes. Subsequently, we systematically analysed ES proteins using computational methods. Of these 4,710 proteins, 2,490 (52.8%) had orthologues in Caenorhabditis elegans, whereas 621 (13.8%) appeared to be novel, currently having no significant match to any molecule available in public databases. Of the C. elegans homologues, 267 had strong “loss-of-function” phenotypes by RNA interference (RNAi) in this nematode. We could functionally classify 1,948 (41.3%) sequences using the Gene Ontology (GO) terms, establish pathway associations for 573 (12.2%) sequences using Kyoto Encyclopaedia of Genes and Genomes (KEGG), and identify protein interaction partners for 1,774 (37.6%) molecules. We also mapped 758 (16.1%) proteins to protein domains including the nematode-specific protein family “transthyretin-like” and “chromadorea ALT,” considered as vaccine candidates against filariasis in humans. Conclusions We report the large-scale analysis of ES proteins inferred from EST data for a range of parasitic nematodes. This set of ES proteins provides an inventory of known and novel members of ES proteins as a

  1. A Quorum-Sensing Antagonist Targets Both Membrane-Bound and Cytoplasmic Receptors And Controls Bacterial Pathogenicity

    PubMed Central

    Swem, Lee R.; Swem, Danielle L.; O’Loughlin, Colleen T.; Gatmaitan, Raleene; Zhao, Bixiao; Ulrich, Scott M.; Bassler, Bonnie L.

    2009-01-01

    Summary Quorum sensing is a process of bacterial communication involving production and detection of secreted molecules called autoinducers. Gram-negative bacteria use acyl-homoserine lactone (AHL) autoinducers, which are detected by one of two receptor types. First, cytoplasmic LuxR-type receptors bind accumulated intracellular AHLs. AHL-LuxR complexes bind DNA and alter gene expression. Second, membrane-bound LuxN-type receptors bind accumulated extracellular AHLs. AHL-LuxN complexes relay information internally by phosphorylation cascades that direct gene-expression changes. Here we show that a small molecule, previously identified as an antagonist of LuxN-type receptors, is also a potent antagonist of the LuxR family, despite differences in receptor structure, localization, AHL specificity, and signaling mechanism. Derivatives were synthesized and optimized for potency, and in each case, we characterized the mode of action of antagonism. The most potent antagonist protects Caenorhabditis elegans from quorum-sensing-mediated killing by Chromobacterium violaceum, validating the notion that targeting quorum sensing has potential for antimicrobial drug development. PMID:19647512

  2. Judy Estes Hall (1940-2015).

    PubMed

    Sammons, Morgan T; Boucher, Andrew

    2016-01-01

    Presents an obituary for Judy Estes Hall, who passed away on November 24, 2015. Hall served as the Executive Officer of the National Register of Health Service Psychologists until her retirement in 2013. She is a recognized expert in the development of education and training standards for the profession of psychology, she also made significant contributions in the field of international psychology, where she was a renowned expert in cross-national credentialing and an advocate for commonality in licensing standards. She was the coauthor of one edited volume and author of more than 60 journal articles, book chapters, and professional publications. A passionate advocate for the advancement of women in psychology, a devoted mother and grandmother, a connoisseur of wine and international traveler extraordinaire, she touched the personal and professional lives of many. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  3. Correlation between light levels and the development of deprivation myopia.

    PubMed

    Karouta, Cindy; Ashby, Regan Scott

    2014-12-09

    In chicks, daily exposure to bright light (15,000 lux) retards the development of form-deprivation myopia (FDM) by roughly 60%. This study investigated whether higher light intensities increase the amount of protection against FDM, and whether protection and light intensity are correlated. Furthermore, we examined if exposure to bright light can prevent the progression of FDM or whether it affects only the onset of experimental myopia. Experiment 1: Chicks wore translucent diffusers monocularly for a period of 7 days, with exposure to one of five light intensities (500, 10,000, 20,000, 30,000, and 40,000 lux, n = 12 per group). Experiment 2: Chickens wore translucent diffusers monocularly for 11 days and were split into three groups: (1) chicks reared under 500 lux, (2) chicks reared under 40,000 lux, and (3) chicks reared under 500 lux for the first 4 days and 40,000 lux for the remaining 7 days. A significant correlation was observed between log light intensity and the development of FDM, with a lesser myopic refraction (F (28, 330) = 60.86, P < 0.0001) and shorter axial length (F (4, 20) = 8.87, P < 0.0001) seen with increasing light intensities. The progression of FDM was halted in chicks that were switched from 500 to 40,000 lux. The level of protection from the development of FDM increases with increasing light intensity. Daily exposure to 40,000 lux almost completely prevents the onset of FDM and, once myopia is established, halts further progression. Copyright 2015 The Association for Research in Vision and Ophthalmology, Inc.

  4. Utility of EST-derived SSR in cultivated peanut (Arachis hypogaea L.) and Arachis wild species

    PubMed Central

    Liang, Xuanqiang; Chen, Xiaoping; Hong, Yanbin; Liu, Haiyan; Zhou, Guiyuan; Li, Shaoxiong; Guo, Baozhu

    2009-01-01

    Background Lack of sufficient molecular markers hinders current genetic research in peanuts (Arachis hypogaea L.). It is necessary to develop more molecular markers for potential use in peanut genetic research. With the development of peanut EST projects, a vast amount of available EST sequence data has been generated. These data offered an opportunity to identify SSR in ESTs by data mining. Results In this study, we investigated 24,238 ESTs for the identification and development of SSR markers. In total, 881 SSRs were identified from 780 SSR-containing unique ESTs. On an average, one SSR was found per 7.3 kb of EST sequence with tri-nucleotide motifs (63.9%) being the most abundant followed by di- (32.7%), tetra- (1.7%), hexa- (1.0%) and penta-nucleotide (0.7%) repeat types. The top six motifs included AG/TC (27.7%), AAG/TTC (17.4%), AAT/TTA (11.9%), ACC/TGG (7.72%), ACT/TGA (7.26%) and AT/TA (6.3%). Based on the 780 SSR-containing ESTs, a total of 290 primer pairs were successfully designed and used for validation of the amplification and assessment of the polymorphism among 22 genotypes of cultivated peanuts and 16 accessions of wild species. The results showed that 251 primer pairs yielded amplification products, of which 26 and 221 primer pairs exhibited polymorphism among the cultivated and wild species examined, respectively. Two to four alleles were found in cultivated peanuts, while 3–8 alleles presented in wild species. The apparent broad polymorphism was further confirmed by cloning and sequencing of amplified alleles. Sequence analysis of selected amplified alleles revealed that allelic diversity could be attributed mainly to differences in repeat type and length in the microsatellite regions. In addition, a few single base mutations were observed in the microsatellite flanking regions. Conclusion This study gives an insight into the frequency, type and distribution of peanut EST-SSRs and demonstrates successful development of EST-SSR markers in

  5. Expressed sequence tag (EST) analysis of the pine wood nematode Bursaphelenchus xylophilus and B. mucronatus.

    PubMed

    Kikuchi, Taisei; Aikawa, Takuya; Kosaka, Hajime; Pritchard, Leighton; Ogura, Nobuo; Jones, John T

    2007-09-01

    Most Bursaphelenchus species feed on fungi that colonise dead or dying trees. However, Bursaphelenchus xylophilus is unique in that in addition to feeding on fungi it has the capacity to be a parasite of live pine trees. We present an analysis of over 13,000 expressed sequence tags (ESTs) from B. xylophilus and, by way of contrast, over 3000 ESTs from a closely related species that does not parasitise plants as readily; B. mucronatus. Four libraries from B. xylophilus, from a variety of life stages including fungal feeding nematodes, nematodes extracted from plants and dauer-like stage nematodes, and one library from B. mucronatus were constructed and used to generate ESTs. Contig analysis showed that the 13,327 B. xylophilus ESTs could be grouped into 2110 contigs and 4377 singletons giving a total of 6487 identified genes. Similarly the 3193 B. mucronatus ESTs yielded a total of 2219 identified genes from 425 contigs and 1794 singletons. A variety of proteins potentially important in the parasitic process of B. xylophilus and B. mucronatus, including plant and fungal cell wall degrading enzymes and a novel gene potentially encoding a expansin-like protein that may disrupt non-covalent bonds in the plant cell wall were identified in the libraries. Additionally several gene candidates potentially involved in dauer entry or maintenance were also identified in the EST dataset. The EST sequences from this study will provide a solid base for future research on the biology, pathogenicity and evolutionary history of this nematode group.

  6. EVER-EST: a virtual research environment for Earth Sciences

    NASA Astrophysics Data System (ADS)

    Marelli, Fulvio; Albani, Mirko; Glaves, Helen

    2016-04-01

    There is an increasing requirement for researchers to work collaboratively using common resources whilst being geographically dispersed. By creating a virtual research environment (VRE) using a service oriented architecture (SOA) tailored to the needs of Earth Science (ES) communities, the EVEREST project will provide a range of both generic and domain specific data management services to support a dynamic approach to collaborative research. EVER-EST will provide the means to overcome existing barriers to sharing of Earth Science data and information allowing research teams to discover, access, share and process heterogeneous data, algorithms, results and experiences within and across their communities, including those domains beyond Earth Science. Researchers will be able to seamlessly manage both the data involved in their computationally intensive disciplines and the scientific methods applied in their observations and modelling, which lead to the specific results that need to be attributable, validated and shared both within the community and more widely e.g. in the form of scholarly communications. Central to the EVEREST approach is the concept of the Research Object (RO) , which provides a semantically rich mechanism to aggregate related resources about a scientific investigation so that they can be shared together using a single unique identifier. Although several e-laboratories are incorporating the research object concept in their infrastructure, the EVER-EST VRE will be the first infrastructure to leverage the concept of Research Objects and their application in observational rather than experimental disciplines. Development of the EVEREST VRE will leverage the results of several previous projects which have produced state-of-the-art technologies for scientific data management and curation as well those which have developed models, techniques and tools for the preservation of scientific methods and their implementation in computational forms such as

  7. From biomedicine to natural history research: EST resources for ambystomatid salamanders

    PubMed Central

    Putta, Srikrishna; Smith, Jeramiah J; Walker, John A; Rondet, Mathieu; Weisrock, David W; Monaghan, James; Samuels, Amy K; Kump, Kevin; King, David C; Maness, Nicholas J; Habermann, Bianca; Tanaka, Elly; Bryant, Susan V; Gardiner, David M; Parichy, David M; Voss, S Randal

    2004-01-01

    Background Establishing genomic resources for closely related species will provide comparative insights that are crucial for understanding diversity and variability at multiple levels of biological organization. We developed ESTs for Mexican axolotl (Ambystoma mexicanum) and Eastern tiger salamander (A. tigrinum tigrinum), species with deep and diverse research histories. Results Approximately 40,000 quality cDNA sequences were isolated for these species from various tissues, including regenerating limb and tail. These sequences and an existing set of 16,030 cDNA sequences for A. mexicanum were processed to yield 35,413 and 20,599 high quality ESTs for A. mexicanum and A. t. tigrinum, respectively. Because the A. t. tigrinum ESTs were obtained primarily from a normalized library, an approximately equal number of contigs were obtained for each species, with 21,091 unique contigs identified overall. The 10,592 contigs that showed significant similarity to sequences from the human RefSeq database reflected a diverse array of molecular functions and biological processes, with many corresponding to genes expressed during spinal cord injury in rat and fin regeneration in zebrafish. To demonstrate the utility of these EST resources, we searched databases to identify probes for regeneration research, characterized intra- and interspecific nucleotide polymorphism, saturated a human – Ambystoma synteny group with marker loci, and extended PCR primer sets designed for A. mexicanum / A. t. tigrinum orthologues to a related tiger salamander species. Conclusions Our study highlights the value of developing resources in traditional model systems where the likelihood of information transfer to multiple, closely related taxa is high, thus simultaneously enabling both laboratory and natural history research. PMID:15310388

  8. The EST Model for Predicting Progressive Damage and Failure of Open Hole Bending Specimens

    NASA Technical Reports Server (NTRS)

    Joseph, Ashith P. K.; Waas, Anthony M.; Pineda, Evan J.

    2016-01-01

    Progressive damage and failure in open hole composite laminate coupons subjected to flexural loading is modeled using Enhanced Schapery Theory (EST). Previous studies have demonstrated that EST can accurately predict the strength of open hole coupons under remote tensile and compressive loading states. This homogenized modeling approach uses single composite shell elements to represent the entire laminate in the thickness direction and significantly reduces computational cost. Therefore, when delaminations are not of concern or are active in the post-peak regime, the version of EST presented here is a good engineering tool for predicting deformation response. Standard coupon level tests provides all the input data needed for the model and they are interpreted in conjunction with finite element (FE) based simulations. Open hole bending test results of three different IM7/8552 carbon fiber composite layups agree well with EST predictions. The model is able to accurately capture the curvature change and deformation localization in the specimen at and during the post catastrophic load drop event.

  9. EST analysis in Ginkgo biloba: an assessment of conserved developmental regulators and gymnosperm specific genes

    PubMed Central

    Brenner, Eric D; Katari, Manpreet S; Stevenson, Dennis W; Rudd, Stephen A; Douglas, Andrew W; Moss, Walter N; Twigg, Richard W; Runko, Suzan J; Stellari, Giulia M; McCombie, WR; Coruzzi, Gloria M

    2005-01-01

    Background Ginkgo biloba L. is the only surviving member of one of the oldest living seed plant groups with medicinal, spiritual and horticultural importance worldwide. As an evolutionary relic, it displays many characters found in the early, extinct seed plants and extant cycads. To establish a molecular base to understand the evolution of seeds and pollen, we created a cDNA library and EST dataset from the reproductive structures of male (microsporangiate), female (megasporangiate), and vegetative organs (leaves) of Ginkgo biloba. Results RNA from newly emerged male and female reproductive organs and immature leaves was used to create three distinct cDNA libraries from which 6,434 ESTs were generated. These 6,434 ESTs from Ginkgo biloba were clustered into 3,830 unigenes. A comparison of our Ginkgo unigene set against the fully annotated genomes of rice and Arabidopsis, and all available ESTs in Genbank revealed that 256 Ginkgo unigenes match only genes among the gymnosperms and non-seed plants – many with multiple matches to genes in non-angiosperm plants. Conversely, another group of unigenes in Gingko had highly significant homology to transcription factors in angiosperms involved in development, including MADS box genes as well as post-transcriptional regulators. Several of the conserved developmental genes found in Ginkgo had top BLAST homology to cycad genes. We also note here the presence of ESTs in G. biloba similar to genes that to date have only been found in gymnosperms and an additional 22 Ginkgo genes common only to genes from cycads. Conclusion Our analysis of an EST dataset from G. biloba revealed genes potentially unique to gymnosperms. Many of these genes showed homology to fully sequenced clones from our cycad EST dataset found in common only with gymnosperms. Other Ginkgo ESTs are similar to developmental regulators in higher plants. This work sets the stage for future studies on Ginkgo to better understand seed and pollen evolution, and to

  10. QuEST: Qualifying Environmentally Sustainable Technologies. Volume 6

    NASA Technical Reports Server (NTRS)

    Lewis, Pattie

    2011-01-01

    QuEST is a publication of the NASA Technology Evaluation for Environmental Risk Mitigation Principal Center (TEERM). This issue contains brief articles on: Risk Identification and Mitigation, Material Management and Substitution Efforts--Hexavalent Chrome-free Coatings and Low volatile organic compounds (VOCs) Coatings, Lead-Free Electronics, Corn-Based Depainting Media; Alternative Energy Efforts Hydrogen Sensors and Solar Air Conditioning. Other TEERM Efforts include: Energy and Water Management and Remediation Technology Collaboration.

  11. GarlicESTdb: an online database and mining tool for garlic EST sequences.

    PubMed

    Kim, Dae-Won; Jung, Tae-Sung; Nam, Seong-Hyeuk; Kwon, Hyuk-Ryul; Kim, Aeri; Chae, Sung-Hwa; Choi, Sang-Haeng; Kim, Dong-Wook; Kim, Ryong Nam; Park, Hong-Seog

    2009-05-18

    Allium sativum., commonly known as garlic, is a species in the onion genus (Allium), which is a large and diverse one containing over 1,250 species. Its close relatives include chives, onion, leek and shallot. Garlic has been used throughout recorded history for culinary, medicinal use and health benefits. Currently, the interest in garlic is highly increasing due to nutritional and pharmaceutical value including high blood pressure and cholesterol, atherosclerosis and cancer. For all that, there are no comprehensive databases available for Expressed Sequence Tags(EST) of garlic for gene discovery and future efforts of genome annotation. That is why we developed a new garlic database and applications to enable comprehensive analysis of garlic gene expression. GarlicESTdb is an integrated database and mining tool for large-scale garlic (Allium sativum) EST sequencing. A total of 21,595 ESTs collected from an in-house cDNA library were used to construct the database. The analysis pipeline is an automated system written in JAVA and consists of the following components: automatic preprocessing of EST reads, assembly of raw sequences, annotation of the assembled sequences, storage of the analyzed information into MySQL databases, and graphic display of all processed data. A web application was implemented with the latest J2EE (Java 2 Platform Enterprise Edition) software technology (JSP/EJB/JavaServlet) for browsing and querying the database, for creation of dynamic web pages on the client side, and for mapping annotated enzymes to KEGG pathways, the AJAX framework was also used partially. The online resources, such as putative annotation, single nucleotide polymorphisms (SNP) and tandem repeat data sets, can be searched by text, explored on the website, searched using BLAST, and downloaded. To archive more significant BLAST results, a curation system was introduced with which biologists can easily edit best-hit annotation information for others to view. The Garlic

  12. Genome sequencing-assisted identification and the first functional validation of N-acyl-homoserine-lactone synthases from the Sphingomonadaceae family

    PubMed Central

    Gan, Han Ming; Dailey, Lucas K.; Halliday, Nigel; Williams, Paul; Hudson, André O.

    2016-01-01

    Background Members of the genus Novosphingobium have been isolated from a variety of environmental niches. Although genomics analyses have suggested the presence of genes associated with quorum sensing signal production e.g., the N-acyl-homoserine lactone (AHL) synthase (luxI) homologs in various Novosphingobium species, to date, no luxI homologs have been experimentally validated. Methods In this study, we report the draft genome of the N-(AHL)-producing bacterium Novosphingobium subterraneum DSM 12447 and validate the functions of predicted luxI homologs from the bacterium through inducible heterologous expression in Agrobacterium tumefaciens strain NTL4. We developed a two-dimensional thin layer chromatography bioassay and used LC-ESI MS/MS analyses to separate, detect and identify the AHL signals produced by the N. subterraneum DSM 12447 strain. Results Three predicted luxI homologs were annotated to the locus tags NJ75_2841 (NovINsub1), NJ75_2498 (NovINsub2), and NJ75_4146 (NovINsub3). Inducible heterologous expression of each luxI homologs followed by LC-ESI MS/MS and two-dimensional reverse phase thin layer chromatography bioassays followed by bioluminescent ccd camera imaging indicate that the three LuxI homologs are able to produce a variety of medium-length AHL compounds. New insights into the LuxI phylogeny was also gleemed as inferred by Bayesian inference. Discussion This study significantly adds to our current understanding of quorum sensing in the genus Novosphingobium and provide the framework for future characterization of the phylogenetically interesting LuxI homologs from members of the genus Novosphingobium and more generally the family Sphingomonadaceae. PMID:27635318

  13. A qrr noncoding RNA deploys four different regulatory mechanisms to optimize quorum-sensing dynamics.

    PubMed

    Feng, Lihui; Rutherford, Steven T; Papenfort, Kai; Bagert, John D; van Kessel, Julia C; Tirrell, David A; Wingreen, Ned S; Bassler, Bonnie L

    2015-01-15

    Quorum sensing is a cell-cell communication process that bacteria use to transition between individual and social lifestyles. In vibrios, homologous small RNAs called the Qrr sRNAs function at the center of quorum-sensing pathways. The Qrr sRNAs regulate multiple mRNA targets including those encoding the quorum-sensing regulatory components luxR, luxO, luxM, and aphA. We show that a representative Qrr, Qrr3, uses four distinct mechanisms to control its particular targets: the Qrr3 sRNA represses luxR through catalytic degradation, represses luxM through coupled degradation, represses luxO through sequestration, and activates aphA by revealing the ribosome binding site while the sRNA itself is degraded. Qrr3 forms different base-pairing interactions with each mRNA target, and the particular pairing strategy determines which regulatory mechanism occurs. Combined mathematical modeling and experiments show that the specific Qrr regulatory mechanism employed governs the potency, dynamics, and competition of target mRNA regulation, which in turn, defines the overall quorum-sensing response. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. AI-2 quorum-sensing inhibitors affect the starvation response and reduce virulence in several Vibrio species, most likely by interfering with LuxPQ.

    PubMed

    Brackman, Gilles; Celen, Shari; Baruah, Kartik; Bossier, Peter; Van Calenbergh, Serge; Nelis, Hans J; Coenye, Tom

    2009-12-01

    The increase of disease outbreaks caused by Vibrio species in aquatic organisms as well as in humans, together with the emergence of antibiotic resistance in Vibrio species, has led to a growing interest in alternative disease control measures. Quorum sensing (QS) is a mechanism for regulating microbial gene expression in a cell density-dependent way. While there is good evidence for the involvement of auto-inducer 2 (AI-2)-based interspecies QS in the control of virulence in multiple Vibrio species, only few inhibitors of this system are known. From the screening of a small panel of nucleoside analogues for their ability to disturb AI-2-based QS, an adenosine derivative with a p-methoxyphenylpropionamide moiety at C-3' emerged as a promising hit. Its mechanism of inhibition was elucidated by measuring the effect on bioluminescence in a series of Vibrio harveyi AI-2 QS mutants. Our results indicate that this compound, as well as a truncated analogue lacking the adenine base, block AI-2-based QS without interfering with bacterial growth. The active compounds affected neither the bioluminescence system as such nor the production of AI-2, but most likely interfered with the signal transduction pathway at the level of LuxPQ in V. harveyi. The most active nucleoside analogue (designated LMC-21) was found to reduce the Vibrio species starvation response, to affect biofilm formation in Vibrio anguillarum, Vibrio vulnificus and Vibrio cholerae, to reduce pigment and protease production in V. anguillarum, and to protect gnotobiotic Artemia from V. harveyi-induced mortality.

  15. Purification, crystallization and preliminary crystallographic analysis of Est25: a ketoprofen-specific hormone-sensitive lipase

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kim, SeungBum; Joo, Sangbum; Yoon, Hyun C.

    2007-07-01

    Est25, a ketoprofen-specific hormone-sensitive lipase from a metagenomic library, was crystallized and diffraction data were collected to 1.49 Å resolution. Ketoprofen, a nonsteroidal anti-inflammatory drug, inhibits the synthesis of prostaglandin. A novel hydrolase (Est25) with high ketoprofen specificity has previously been identified using a metagenomic library from environmental samples. Recombinant Est25 protein with a histidine tag at the N-terminus was expressed in Escherichia coli and purified in a homogenous form. Est25 was crystallized from 2.4 M sodium malonate pH 7.0 and X-ray diffraction data were collected to 1.49 Å using synchrotron radiation. The crystals belong to the monoclinic space groupmore » C2, with unit-cell parameters a = 197.8, b = 95.2, c = 99.4 Å, β = 97.1°.« less

  16. EST! environmentally sustainable transport issue paper : soft measures and transport

    DOT National Transportation Integrated Search

    2002-12-01

    The purpose of this paper was to help guide and even provoke discussion at the workshop to be held in Berlin on 5-6 December, 2002, entitled Communicating Environmentally Sustainable Transport-The roles of soft measures in achieving EST. It's easier ...

  17. Cloning and characterization of a pyrethroid pesticide decomposing esterase gene, Est3385, from Rhodopseudomonas palustris PSB-S.

    PubMed

    Luo, Xiangwen; Zhang, Deyong; Zhou, Xuguo; Du, Jiao; Zhang, Songbai; Liu, Yong

    2018-05-09

    Full length open reading frame of pyrethroid detoxification gene, Est3385, contains 963 nucleotides. This gene was identified and cloned based on the genome sequence of Rhodopseudomonas palustris PSB-S available at the GneBank. The predicted amino acid sequence of Est3385 shared moderate identities (30-46%) with the known homologous esterases. Phylogenetic analysis revealed that Est3385 was a member in the esterase family I. Recombinant Est3385 was heterologous expressed in E. coli, purified and characterized for its substrate specificity, kinetics and stability under various conditions. The optimal temperature and pH for Est3385 were 35 °C and 6.0, respectively. This enzyme could detoxify various pyrethroid pesticides and degrade the optimal substrate fenpropathrin with a Km and Vmax value of 0.734 ± 0.013 mmol·l -1 and 0.918 ± 0.025 U·µg -1 , respectively. No cofactor was found to affect Est3385 activity but substantial reduction of enzymatic activity was observed when metal ions were applied. Taken together, a new pyrethroid degradation esterase was identified and characterized. Modification of Est3385 with protein engineering toolsets should enhance its potential for field application to reduce the pesticide residue from agroecosystems.

  18. Composition-property relationships in (Gd3-xLux)(GayAl5-y)O12:Ce (x = 0, 1, 2, 3 and y = 0, 1, 2, 3, 4) multicomponent garnet scintillators

    NASA Astrophysics Data System (ADS)

    Luo, Jialiang; Wu, Yuntao; Zhang, Guoqing; Zhang, Huaijin; Ren, Guohao

    2013-12-01

    The (LuxGd3-x)(GayAl5-y)O12:Ce (x = 0, 1, 2, 3 and y = 0, 1, 2, 3, 4) scintillating polycrystalline powders were prepared by high temperature solid state reaction method. A pure cubic phase was confirmed in all samples by X-ray diffraction (XRD). X-ray excited luminescence (XEL), photoluminescence excitation and emission spectra were employed to study the influence of Gd3+-Ga3+ admixture on the luminescent mechanism of Ce3+ as well as the energy transfer from Gd3+ to Ce3+. The band-gap structures with varying Gd3+ and Ga3+ content were constructed to understand the luminescence behaviors. In addition, thermoluminescence spectra (TL) were utilized to identify the moving of conduction band (CB) by monitoring the shift of the corresponding TL peaks. Finally, it was found that incorporation of 40 mol% (y = 2) Ga3+ and 33.3-66.7 mol% (x = 1-2) Gd3+ could secure enough energy-separation between CB and 5d1 of Ce3+ avoiding thermal ionization effect at utmost, and bury the antisite defect traps into CB, and in turn achieving the optimum scintillation efficiency.

  19. Effects of forward and backward transitions in light intensities in tau-illuminance curves of the rat motor activity rhythm under constant dim light.

    PubMed

    Cambras, Trinitat; Díez-Noguera, Antoni

    2012-07-01

    Circadian rhythms are strongly influenced by light intensity, the effects of which may persist beyond the duration of light exposure (aftereffects). Here, the authors constructed period-illuminance curves for the motor activity circadian rhythm of male and female rats by recording the effects of a series of small upward and downward steps in light intensity (illuminance ranging between .01 lux of dim red light and 1 lux of white light) on their activity. In all cases, stepwise changes were made in five logarithmic steps (irradiance: dim red light: .692 µW/cm(2) and white light: .006, .016, .044, .12, and .315 µW/cm(2), corresponding, respectively, to .02, .05, .14, .13, and 1 lux measured at cage level), with changes in intensity every 2 wks. One group of rats (DLD) started in dim red light, moved up to 1 lux white light, and then back down to the original light intensity. Another group (LDL) started at 1 lux, moved down to .01 lux, and then back up to the original intensity. Motor activity data were recorded throughout the experiment and tau values, the percentage of variance explained by the rhythm, and the mean motor activity for each stage and group were calculated. The results show differences in the dynamics of tau values between the DLD and LDL groups and between males and females. In the LDL group, the tau values of both males and females were dependent on light intensity, and were similar for the forward and backward transitions. In other words, no aftereffects were found, and no differences were detected between males and females. In the DLD group, however, differences were found between males and females. Males had a tau value of 24 h 20 min under dim red light, 25 h 40 min under 1 lux, and 24 h 50 min on return to dim red light. It is noticeable that the tau values of the backward branch of the illuminance curve contradicted classical predictions, since at .38 and .14 lux the tau values were shorter than those found under the same intensities after

  20. JANE: efficient mapping of prokaryotic ESTs and variable length sequence reads on related template genomes

    PubMed Central

    2009-01-01

    Background ESTs or variable sequence reads can be available in prokaryotic studies well before a complete genome is known. Use cases include (i) transcriptome studies or (ii) single cell sequencing of bacteria. Without suitable software their further analysis and mapping would have to await finalization of the corresponding genome. Results The tool JANE rapidly maps ESTs or variable sequence reads in prokaryotic sequencing and transcriptome efforts to related template genomes. It provides an easy-to-use graphics interface for information retrieval and a toolkit for EST or nucleotide sequence function prediction. Furthermore, we developed for rapid mapping an enhanced sequence alignment algorithm which reassembles and evaluates high scoring pairs provided from the BLAST algorithm. Rapid assembly on and replacement of the template genome by sequence reads or mapped ESTs is achieved. This is illustrated (i) by data from Staphylococci as well as from a Blattabacteria sequencing effort, (ii) mapping single cell sequencing reads is shown for poribacteria to sister phylum representative Rhodopirellula Baltica SH1. The algorithm has been implemented in a web-server accessible at http://jane.bioapps.biozentrum.uni-wuerzburg.de. Conclusion Rapid prokaryotic EST mapping or mapping of sequence reads is achieved applying JANE even without knowing the cognate genome sequence. PMID:19943962

  1. The QuEST for multi-sensor big data ISR situation understanding

    NASA Astrophysics Data System (ADS)

    Rogers, Steven; Culbertson, Jared; Oxley, Mark; Clouse, H. Scott; Abayowa, Bernard; Patrick, James; Blasch, Erik; Trumpfheller, John

    2016-05-01

    The challenges for providing war fighters with the best possible actionable information from diverse sensing modalities using advances in big-data and machine learning are addressed in this paper. We start by presenting intelligence, surveillance, and reconnaissance (ISR) related big-data challenges associated with the Third Offset Strategy. Current approaches to big-data are shown to be limited with respect to reasoning/understanding. We present a discussion of what meaning making and understanding require. We posit that for human-machine collaborative solutions to address the requirements for the strategy a new approach, Qualia Exploitation of Sensor Technology (QuEST), will be required. The requirements for developing a QuEST theory of knowledge are discussed and finally, an engineering approach for achieving situation understanding is presented.

  2. First Microsatellite Markers Developed from Cupuassu ESTs: Application in Diversity Analysis and Cross-Species Transferability to Cacao.

    PubMed

    Ferraz Dos Santos, Lucas; Moreira Fregapani, Roberta; Falcão, Loeni Ludke; Togawa, Roberto Coiti; Costa, Marcos Mota do Carmo; Lopes, Uilson Vanderlei; Peres Gramacho, Karina; Alves, Rafael Moyses; Micheli, Fabienne; Marcellino, Lucilia Helena

    2016-01-01

    The cupuassu tree (Theobroma grandiflorum) (Willd. ex Spreng.) Schum. is a fruitful species from the Amazon with great economical potential, due to the multiple uses of its fruit´s pulp and seeds in the food and cosmetic industries, including the production of cupulate, an alternative to chocolate. In order to support the cupuassu breeding program and to select plants presenting both pulp/seed quality and fungal disease resistance, SSRs from Next Generation Sequencing ESTs were obtained and used in diversity analysis. From 8,330 ESTs, 1,517 contained one or more SSRs (1,899 SSRs identified). The most abundant motifs identified in the EST-SSRs were hepta- and trinucleotides, and they were found with a minimum and maximum of 2 and 19 repeats, respectively. From the 1,517 ESTs containing SSRs, 70 ESTs were selected based on their functional annotation, focusing on pulp and seed quality, as well as resistance to pathogens. The 70 ESTs selected contained 77 SSRs, and among which, 11 were polymorphic in cupuassu genotypes. These EST-SSRs were able to discriminate the cupuassu genotype in relation to resistance/susceptibility to witches' broom disease, as well as to pulp quality (SST/ATT values). Finally, we showed that these markers were transferable to cacao genotypes, and that genome availability might be used as a predictive tool for polymorphism detection and primer design useful for both Theobroma species. To our knowledge, this is the first report involving EST-SSRs from cupuassu and is also a pioneer in the analysis of marker transferability from cupuassu to cacao. Moreover, these markers might contribute to develop or saturate the cupuassu and cacao genetic maps, respectively.

  3. First Microsatellite Markers Developed from Cupuassu ESTs: Application in Diversity Analysis and Cross-Species Transferability to Cacao

    PubMed Central

    Ferraz dos Santos, Lucas; Moreira Fregapani, Roberta; Falcão, Loeni Ludke; Togawa, Roberto Coiti; Costa, Marcos Mota do Carmo; Lopes, Uilson Vanderlei; Peres Gramacho, Karina; Alves, Rafael Moyses

    2016-01-01

    The cupuassu tree (Theobroma grandiflorum) (Willd. ex Spreng.) Schum. is a fruitful species from the Amazon with great economical potential, due to the multiple uses of its fruit´s pulp and seeds in the food and cosmetic industries, including the production of cupulate, an alternative to chocolate. In order to support the cupuassu breeding program and to select plants presenting both pulp/seed quality and fungal disease resistance, SSRs from Next Generation Sequencing ESTs were obtained and used in diversity analysis. From 8,330 ESTs, 1,517 contained one or more SSRs (1,899 SSRs identified). The most abundant motifs identified in the EST-SSRs were hepta- and trinucleotides, and they were found with a minimum and maximum of 2 and 19 repeats, respectively. From the 1,517 ESTs containing SSRs, 70 ESTs were selected based on their functional annotation, focusing on pulp and seed quality, as well as resistance to pathogens. The 70 ESTs selected contained 77 SSRs, and among which, 11 were polymorphic in cupuassu genotypes. These EST-SSRs were able to discriminate the cupuassu genotype in relation to resistance/susceptibility to witches’ broom disease, as well as to pulp quality (SST/ATT values). Finally, we showed that these markers were transferable to cacao genotypes, and that genome availability might be used as a predictive tool for polymorphism detection and primer design useful for both Theobroma species. To our knowledge, this is the first report involving EST-SSRs from cupuassu and is also a pioneer in the analysis of marker transferability from cupuassu to cacao. Moreover, these markers might contribute to develop or saturate the cupuassu and cacao genetic maps, respectively. PMID:26949967

  4. Generation and Analysis of Expressed Sequence Tags (ESTs) from Halophyte Atriplex canescens to Explore Salt-Responsive Related Genes

    PubMed Central

    Li, Jingtao; Sun, Xinhua; Yu, Gang; Jia, Chengguo; Liu, Jinliang; Pan, Hongyu

    2014-01-01

    Little information is available on gene expression profiling of halophyte A. canescens. To elucidate the molecular mechanism for stress tolerance in A. canescens, a full-length complementary DNA library was generated from A. canescens exposed to 400 mM NaCl, and provided 343 high-quality ESTs. In an evaluation of 343 valid EST sequences in the cDNA library, 197 unigenes were assembled, among which 190 unigenes (83.1% ESTs) were identified according to their significant similarities with proteins of known functions. All the 343 EST sequences have been deposited in the dbEST GenBank under accession numbers JZ535802 to JZ536144. According to Arabidopsis MIPS functional category and GO classifications, we identified 193 unigenes of the 311 annotations EST, representing 72 non-redundant unigenes sharing similarities with genes related to the defense response. The sets of ESTs obtained provide a rich genetic resource and 17 up-regulated genes related to salt stress resistance were identified by qRT-PCR. Six of these genes may contribute crucially to earlier and later stage salt stress resistance. Additionally, among the 343 unigenes sequences, 22 simple sequence repeats (SSRs) were also identified contributing to the study of A. canescens resources. PMID:24960361

  5. Development and Application of a Salmonid EST Database and cDNA Microarray: Data Mining and Interspecific Hybridization Characteristics

    PubMed Central

    Rise, Matthew L.; von Schalburg, Kristian R.; Brown, Gordon D.; Mawer, Melanie A.; Devlin, Robert H.; Kuipers, Nathanael; Busby, Maura; Beetz-Sargent, Marianne; Alberto, Roberto; Gibbs, A. Ross; Hunt, Peter; Shukin, Robert; Zeznik, Jeffrey A.; Nelson, Colleen; Jones, Simon R.M.; Smailus, Duane E.; Jones, Steven J.M.; Schein, Jacqueline E.; Marra, Marco A.; Butterfield, Yaron S.N.; Stott, Jeff M.; Ng, Siemon H.S.; Davidson, William S.; Koop, Ben F.

    2004-01-01

    We report 80,388 ESTs from 23 Atlantic salmon (Salmo salar) cDNA libraries (61,819 ESTs), 6 rainbow trout (Oncorhynchus mykiss) cDNA libraries (14,544 ESTs), 2 chinook salmon (Oncorhynchus tshawytscha) cDNA libraries (1317 ESTs), 2 sockeye salmon (Oncorhynchus nerka) cDNA libraries (1243 ESTs), and 2 lake whitefish (Coregonus clupeaformis) cDNA libraries (1465 ESTs). The majority of these are 3′ sequences, allowing discrimination between paralogs arising from a recent genome duplication in the salmonid lineage. Sequence assembly reveals 28,710 different S. salar, 8981 O. mykiss, 1085 O. tshawytscha, 520 O. nerka, and 1176 C. clupeaformis putative transcripts. We annotate the submitted portion of our EST database by molecular function. Higher- and lower-molecular-weight fractions of libraries are shown to contain distinct gene sets, and higher rates of gene discovery are associated with higher-molecular weight libraries. Pyloric caecum library group annotations indicate this organ may function in redox control and as a barrier against systemic uptake of xenobiotics. A microarray is described, containing 7356 salmonid elements representing 3557 different cDNAs. Analyses of cross-species hybridizations to this cDNA microarray indicate that this resource may be used for studies involving all salmonids. PMID:14962987

  6. The barley EST DNA Replication and Repair Database (bEST-DRRD) as a tool for the identification of the genes involved in DNA replication and repair.

    PubMed

    Gruszka, Damian; Marzec, Marek; Szarejko, Iwona

    2012-06-14

    The high level of conservation of genes that regulate DNA replication and repair indicates that they may serve as a source of information on the origin and evolution of the species and makes them a reliable system for the identification of cross-species homologs. Studies that had been conducted to date shed light on the processes of DNA replication and repair in bacteria, yeast and mammals. However, there is still much to be learned about the process of DNA damage repair in plants. These studies, which were conducted mainly using bioinformatics tools, enabled the list of genes that participate in various pathways of DNA repair in Arabidopsis thaliana (L.) Heynh to be outlined; however, information regarding these mechanisms in crop plants is still very limited. A similar, functional approach is particularly difficult for a species whose complete genomic sequences are still unavailable. One of the solutions is to apply ESTs (Expressed Sequence Tags) as the basis for gene identification. For the construction of the barley EST DNA Replication and Repair Database (bEST-DRRD), presented here, the Arabidopsis nucleotide and protein sequences involved in DNA replication and repair were used to browse for and retrieve the deposited sequences, derived from four barley (Hordeum vulgare L.) sequence databases, including the "Barley Genome version 0.05" database (encompassing ca. 90% of barley coding sequences) and from two databases covering the complete genomes of two monocot models: Oryza sativa L. and Brachypodium distachyon L. in order to identify homologous genes. Sequences of the categorised Arabidopsis queries are used for browsing the repositories, which are located on the ViroBLAST platform. The bEST-DRRD is currently used in our project during the identification and validation of the barley genes involved in DNA repair. The presented database provides information about the Arabidopsis genes involved in DNA replication and repair, their expression patterns and models

  7. Preparing and Analyzing Expressed Sequence Tags (ESTs) Library for the Mammary Tissue of Local Turkish Kivircik Sheep

    PubMed Central

    Omeroglu Ulu, Zehra; Ulu, Salih; Un, Cemal; Ozdem Oztabak, Kemal; Altunatmaz, Kemal

    2017-01-01

    Kivircik sheep is an important local Turkish sheep according to its meat quality and milk productivity. The aim of this study was to analyze gene expression profiles of both prenatal and postnatal stages for the Kivircik sheep. Therefore, two different cDNA libraries, which were taken from the same Kivircik sheep mammary gland tissue at prenatal and postnatal stages, were constructed. Total 3072 colonies which were randomly selected from the two libraries were sequenced for developing a sheep ESTs collection. We used Phred/Phrap computer programs for analysis of the raw EST and readable EST sequences were assembled with the CAP3 software. Putative functions of all unique sequences and statistical analysis were determined by Geneious software. Total 422 ESTs have over 80% similarity to known sequences of other organisms in NCBI classified by Panther database for the Gene Ontology (GO) category. By comparing gene expression profiles, we observed some putative genes that may be relative to reproductive performance or play important roles in milk synthesis and secretion. A total of 2414 ESTs have been deposited to the NCBI GenBank database (GW996847–GW999260). EST data in this study have provided a new source of information to functional genome studies of sheep. PMID:28239610

  8. Photobacterium kishitanii sp. nov., a luminous marine bacterium symbiotic with deep-sea fishes.

    PubMed

    Ast, Jennifer C; Cleenwerck, Ilse; Engelbeen, Katrien; Urbanczyk, Henryk; Thompson, Fabiano L; De Vos, Paul; Dunlap, Paul V

    2007-09-01

    Six representatives of a luminous bacterium commonly found in association with deep, cold-dwelling marine fishes were isolated from the light organs and skin of different fish species. These bacteria were Gram-negative, catalase-positive, and weakly oxidase-positive or oxidase-negative. Morphologically, cells of these strains were coccoid or coccoid-rods, occurring singly or in pairs, and motile by means of polar flagellation. After growth on seawater-based agar medium at 22 degrees C for 18 h, colonies were small, round and white, with an intense cerulean blue luminescence. Analysis of 16S rRNA gene sequence similarity placed these bacteria in the genus Photobacterium. Phylogenetic analysis based on seven housekeeping gene sequences (16S rRNA gene, gapA, gyrB, pyrH, recA, rpoA and rpoD), seven gene sequences of the lux operon (luxC, luxD, luxA, luxB, luxF, luxE and luxG) and four gene sequences of the rib operon (ribE, ribB, ribH and ribA), resolved the six strains as members of the genus Photobacterium and as a clade distinct from other species of Photobacterium. These strains were most closely related to Photobacterium phosphoreum and Photobacterium iliopiscarium. DNA-DNA hybridization values between the designated type strain, Photobacterium kishitanii pjapo.1.1(T), and P. phosphoreum LMG 4233(T), P. iliopiscarium LMG 19543(T) and Photobacterium indicum LMG 22857(T) were 51, 43 and 19 %, respectively. In AFLP analysis, the six strains clustered together, forming a group distinct from other analysed species. The fatty acid C(17 : 0) cyclo was present in these bacteria, but not in P. phosphoreum, P. iliopiscarium or P. indicum. A combination of biochemical tests (arginine dihydrolase and lysine decarboxylase) differentiates these strains from P. phosphoreum and P. indicum. The DNA G+C content of P. kishitanii pjapo.1.1(T) is 40.2 %, and the genome size is approximately 4.2 Mbp, in the form of two circular chromosomes. These strains represent a novel species, for

  9. Exploring the temporal structure of heterochronous sequences using TempEst (formerly Path-O-Gen).

    PubMed

    Rambaut, Andrew; Lam, Tommy T; Max Carvalho, Luiz; Pybus, Oliver G

    2016-01-01

    Gene sequences sampled at different points in time can be used to infer molecular phylogenies on a natural timescale of months or years, provided that the sequences in question undergo measurable amounts of evolutionary change between sampling times. Data sets with this property are termed heterochronous and have become increasingly common in several fields of biology, most notably the molecular epidemiology of rapidly evolving viruses. Here we introduce the cross-platform software tool, TempEst (formerly known as Path-O-Gen), for the visualization and analysis of temporally sampled sequence data. Given a molecular phylogeny and the dates of sampling for each sequence, TempEst uses an interactive regression approach to explore the association between genetic divergence through time and sampling dates. TempEst can be used to (1) assess whether there is sufficient temporal signal in the data to proceed with phylogenetic molecular clock analysis, and (2) identify sequences whose genetic divergence and sampling date are incongruent. Examination of the latter can help identify data quality problems, including errors in data annotation, sample contamination, sequence recombination, or alignment error. We recommend that all users of the molecular clock models implemented in BEAST first check their data using TempEst prior to analysis.

  10. Mining and characterization of EST-SSR markers for Zingiber officinale Roscoe with transferability to other species of Zingiberaceae.

    PubMed

    Awasthi, Praveen; Singh, Ashish; Sheikh, Gulfam; Mahajan, Vidushi; Gupta, Ajai Prakash; Gupta, Suphla; Bedi, Yashbir S; Gandhi, Sumit G

    2017-10-01

    Zingiber officinale is a model spice herb, well known for its medicinal value. It is primarily a vegetatively propagated commercial crop. However, considerable diversity in its morphology, fiber content and chemoprofiles has been reported. The present study explores the utility of EST-derived markers in studying genetic diversity in different accessions of Z. officinale and their cross transferability within the Zingiberaceae family. A total of 38,115 ESTs sequences were assembled to generate 7850 contigs and 10,762 singletons. SSRs were searched in the unigenes and 515 SSR-containing ESTs were identified with a frequency of 1 SSR per 25.21 kb of the genome. These ESTs were also annotated using BLAST2GO. Primers were designed for 349 EST-SSRs and 25 primer pairs were randomly picked for EST SSR study. Out of these, 16 primer pairs could be optimized for amplification in different accessions of Z. officinale as well as other species belonging to Zingiberaceae. GES454, GES466, GES480 and GES486 markers were found to exhibit 100% cross-transferability among different members of Zingiberaceae.

  11. Characterization and multiplexing of EST-SSR primers in Cynodon (Poaceae) species1.

    PubMed

    Jewell, Margaret C; Frere, Celine H; Prentis, Peter J; Lambrides, Christopher J; Godwin, Ian D

    2010-10-01

    Cynodon species are multiple-use grasses that display varying levels of adaptation to biotic and abiotic stress. Previously identified EST-SSR primers were characterized and multiplexed to assess the level of genetic diversity present within a collection of almost 1200 Cynodon accessions from across Australia. • Two multiplex reactions were developed comprising a total of 16 EST-SSR markers. All SSR markers amplified across different Cynodon species and different levels of ploidy. The number of alleles ranged from one to eight per locus and the total number of alleles for the germplasm collection was 79. • The 16 markers show sufficient variation for the characterization of Cynodon core collections and analysis of population genetic diversity in Cynodon grasses.

  12. EST Analysis of Hop Glandular Trichomes Identifies an O-Methyltransferase That Catalyzes the Biosynthesis of Xanthohumol[W][OA

    PubMed Central

    Nagel, Jana; Culley, Lana K.; Lu, Yuping; Liu, Enwu; Matthews, Paul D.; Stevens, Jan F.; Page, Jonathan E.

    2008-01-01

    The glandular trichomes (lupulin glands) of hop (Humulus lupulus) synthesize essential oils and terpenophenolic resins, including the bioactive prenylflavonoid xanthohumol. To dissect the biosynthetic processes occurring in lupulin glands, we sequenced 10,581 ESTs from four trichome-derived cDNA libraries. ESTs representing enzymes of terpenoid biosynthesis, including all of the steps of the methyl 4-erythritol phosphate pathway, were abundant in the EST data set, as were ESTs for the known type III polyketide synthases of bitter acid and xanthohumol biosynthesis. The xanthohumol biosynthetic pathway involves a key O-methylation step. Four S-adenosyl-l-methionine–dependent O-methyltransferases (OMTs) with similarity to known flavonoid-methylating enzymes were present in the EST data set. OMT1, which was the most highly expressed OMT based on EST abundance and RT-PCR analysis, performs the final reaction in xanthohumol biosynthesis by methylating desmethylxanthohumol to form xanthohumol. OMT2 accepted a broad range of substrates, including desmethylxanthohumol, but did not form xanthohumol. Mass spectrometry and proton nuclear magnetic resonance analysis showed it methylated xanthohumol to 4-O-methylxanthohumol, which is not known from hop. OMT3 was inactive with all substrates tested. The lupulin gland-specific EST data set expands the genomic resources for H. lupulus and provides further insight into the metabolic specialization of glandular trichomes. PMID:18223037

  13. Enantiomeric separation of type I and type II pyrethroid insecticides with different chiral stationary phases by reversed-phase high-performance liquid chromatography.

    PubMed

    Zhang, Ping; Yu, Qian; He, Xiulong; Qian, Kun; Xiao, Wei; Xu, Zhifeng; Li, Tian; He, Lin

    2018-04-01

    The enantiomeric separation of type I (bifenthrin, BF) and type II (lambda-cyhalothrin, LCT) pyrethroid insecticides on Lux Cellulose-1, Lux Cellulose-3, and Chiralpak IC chiral columns was investigated by reversed-phase high-performance liquid chromatography. Methanol/water or acetonitrile/water was used as mobile phase at a flow rate of 0.8 mL/min. The effects of chiral stationary phase, mobile phase composition, column temperature, and thermodynamic parameters on enantiomer separation were carefully studied. Bifenthrin got a partial separation on Lux Cellulose-1 column and baseline separation on Lux Cellulose-3 column, while LCT enantiomers could be completely separated on both Lux Cellulose-1 and Lux Cellulose-3 columns. Chiralpak IC provided no separation ability for both BF and LCT. Retention factor (k) and selectivity factor (α) decreased with the column temperature increasing from 10°C to 40°C for both BF and LCT enantiomers. Thermodynamic parameters including ∆H and ∆S were also calculated, and the maximum R s were not always obtained at lowest temperature. Furthermore, the quantitative analysis methods for BF and LCT enantiomers in soil and water were also established. Such results provide a new approach for pyrethroid separation under reversed-phase condition and contribute to environmental risk assessment of pyrethroids at enantiomer level. © 2017 Wiley Periodicals, Inc.

  14. The bioluminescent Listeria monocytogenes strain Xen32 is defective in flagella expression and highly attenuated in orally infected BALB/cJ mice.

    PubMed

    Bergmann, Silke; Rohde, Manfred; Schughart, Klaus; Lengeling, Andreas

    2013-07-15

    In vivo bioluminescence imaging (BLI) is a powerful method for the analysis of host-pathogen interactions in small animal models. The commercially available bioluminescent Listeria monocytogenes strain Xen32 is commonly used to analyse immune functions in knockout mice and pathomechanisms of listeriosis. To analyse and image listerial dissemination after oral infection we have generated a murinised Xen32 strain (Xen32-mur) which expresses a previously described mouse-adapted internalin A. This strain was used alongside the Xen32 wild type strain and the bioluminescent L. monocytogenes strains EGDe-lux and murinised EGDe-mur-lux to characterise bacterial dissemination in orally inoculated BALB/cJ mice. After four days of infection, Xen32 and Xen32-mur infected mice displayed consistently higher rates of bioluminescence compared to EGDe-lux and EGDe-mur-lux infected animals. However, surprisingly both Xen32 strains showed attenuated virulence in orally infected BALB/c mice that correlated with lower bacterial burden in internal organs at day 5 post infection, smaller losses in body weights and increased survival compared to EGDe-lux or EGDe-mur-lux inoculated animals. The Xen32 strain was made bioluminescent by integration of a lux-kan transposon cassette into the listerial flaA locus. We show here that this integration results in Xen32 in a flaA frameshift mutation which makes this strain flagella deficient. The bioluminescent L. monocytogenes strain Xen32 is deficient in flagella expression and highly attenuated in orally infected BALB/c mice. As this listerial strain has been used in many BLI studies of murine listeriosis, it is important that the scientific community is aware of its reduced virulence in vivo.

  15. Development and characterization of microsatellite markers for the Pacific abalone ( Haliotis discus) via EST database mining

    NASA Astrophysics Data System (ADS)

    Zhan, Aibin; Bao, Zhenmin; Wang, Mingling; Chang, Dan; Yuan, Jian; Wang, Xiaolong; Hu, Xiaoli; Liang, Chengzhu; Hu, Jingjie

    2008-05-01

    The EST database of the Pacific abalone ( Haliotis discus) was mined for developing microsatellite markers. A total of 1476 EST sequences were registered in GenBank when data mining was performed. Fifty sequences (approximately 3.4%) were found to contain one or more microsatellites. Based on the length and GC content of the flanking regions, cluster analysis and BLASTN, 13 microsatellite-containing ESTs were selected for PCR primer design. The results showed that 10 out of 13 primer pairs could amplify scorable PCR products and showed polymorphism. The number of alleles ranged from 2 to 13 and the values of H o and H e varied from 0.1222 to 0.8611 and 0.2449 to 0.9311, respectively. No significant linkage disequilibrium (LD) between any pairs of these loci was found, and 6 of 10 loci conformed to the Hardy-Weinberg equilibrium (HWE). These EST-SSRs are therefore potential tools for studies of intraspecies variation and hybrid identification.

  16. [EST-SSR identification, markers development of Ligusticum chuanxiong based on Ligusticum chuanxiong transcriptome sequences].

    PubMed

    Yuan, Can; Peng, Fang; Yang, Ze-Mao; Zhong, Wen-Juan; Mou, Fang-Sheng; Gong, Yi-Yun; Ji, Pei-Cheng; Pu, De-Qiang; Huang, Hai-Yan; Yang, Xiao; Zhang, Chao

    2017-09-01

    Ligusticum chuanxiong is a well-known traditional Chinese medicine plant. The study on its molecular markers development and germplasm resources is very important. In this study, we obtained 24 422 unigenes by assembling transcriptome sequencing reads of L. chuanxiong root. EST-SSR was detected and 4 073 SSR loci were identified. EST-SSR distribution and characteristic analysis results showed that the mono-nucleotide repeats were the main repeat types, accounting for 41.0%. In addition, the sequences containing SSR were functionally annotated in Gene Ontology (GO) and KEGG pathway and were assigned to 49 GO categories, 242 KEGG pathways, among them 2 201 sequences were annotated against Nr database. By validating 235 EST-SSRs,74 primer pairs were ultimately proved to have high quality amplification. Subsequently, genetic diversity analysis, UPGMA cluster analysis, PCoA analysis and population structure analysis of 34 L. chuanxiong germplasm resources were carried out with 74 primer pairs. In both UPGMA tree and PCoA results, L. chuanxiong resources were clustered into two groups, which are believed to be partial related to their geographical distribution. In this study, EST-SSRs in L. chuanxiong was firstly identified, and newly developed molecular markers would contribute significantly to further genetic diversity study, the purity detection, gene mapping, and molecular breeding. Copyright© by the Chinese Pharmaceutical Association.

  17. ESTminer: a Web interface for mining EST contig and cluster databases.

    PubMed

    Huang, Yecheng; Pumphrey, Janie; Gingle, Alan R

    2005-03-01

    ESTminer is a Web application and database schema for interactive mining of expressed sequence tag (EST) contig and cluster datasets. The Web interface contains a query frame that allows the selection of contigs/clusters with specific cDNA library makeup or a threshold number of members. The results are displayed as color-coded tree nodes, where the color indicates the fractional size of each cDNA library component. The nodes are expandable, revealing library statistics as well as EST or contig members, with links to sequence data, GenBank records or user configurable links. Also, the interface allows 'queries within queries' where the result set of a query is further filtered by the subsequent query. ESTminer is implemented in Java/JSP and the package, including MySQL and Oracle schema creation scripts, is available from http://cggc.agtec.uga.edu/Data/download.asp agingle@uga.edu.

  18. Dim Light at Night Increases Body Mass of Female Mice

    PubMed Central

    Aubrecht, Taryn G.; Jenkins, Richelle; Nelson, Randy J.

    2016-01-01

    During the past century the prevalence of light at night has increased in parallel with obesity rates. Dim light at night (dLAN) increases body mass in male mice. However, the effects of light at night on female body mass remain unspecified. Thus, female mice were exposed to a standard light/dark (LD; 16h light at ~150 lux/8h dark at ~0 lux) cycle or to light/dim light at night (dLAN; 16h light at ~150 lux/8h dim light at ~5 lux) cycles for six weeks. Females exposed to dLAN increased the rate of change in body mass compared to LD mice despite reduced total food intake during weeks five and six, suggesting that dLAN disrupted circadian rhythms resulting in deranged metabolism. PMID:25431079

  19. Light intensity and the oestrous cycle in albino and normally pigmented mice.

    PubMed

    Donnelly, H; Saibaba, P

    1993-10-01

    The effects of light intensity (15-20 lux & 220-290 lux) on the oestrous cycle of albino and normally pigmented mice were examined. The oestrous cycle of both types of mice was shorter at the lower intensity but the difference was significant only with the black mice. The proportion of albino mice from which embryos were recovered was significantly smaller than the proportion of black mice at 15-20 lux but not at 220-290 lux. No significant differences due to strain or light intensity were found in the number of embryos recovered. We conclude that pigmented mice respond in the same way as albino mice to changes in light intensity within the range normally found in laboratory animal accommodation. That is, increased light intensity prolongs the oestrous cycle and the period of vaginal cornification.

  20. Identification, validation and cross-species transferability of novel Lavandula EST-SSRs.

    PubMed

    Adal, Ayelign M; Demissie, Zerihun A; Mahmoud, Soheil S

    2015-04-01

    We identified and characterized EST-SSRs with strong discrimination power against Lavandula angustifolia and Lavandula x intermedia . The markers also showed considerable cross-species transferability rate into six related Lavandula species. Lavenders (Lavandula) are important economical crops grown around the globe for essential oil production. In an attempt to develop genetic markers for these plants, we analyzed over 13,000 unigenes developed from L. angustifolia and L. x intermedia EST databases, and identified 3,459 simple sequence repeats (SSR), which were dominated by trinucleotides (41.2 %) and dinucleotides (31.45 %). Approximately, 19 % of the unigenes contained at least one SSR marker, over 60 % of which were localized in the UTRs. Only 252 EST-SSRs were 18 bp or longer from which 31 loci were validated, and 24 amplified discrete fragments with 85 % polymorphism in L. x intermedia and L. angustifolia. The average number of alleles in L. x intermedia and L. angustifolia were 3.42 and 3.71 per marker with average PIC values of 0.47 and 0.52, respectively. These values suggest a moderate to strong level of informativeness for the markers, with some loci producing unique fingerprints. The cross-species transferability rate of the markers ranges 50-100 % across eight species. The utility of these markers was assessed in eight Lavandula species and 15 L. angustifolia and L. x intermedia cultivars, and the dendrogram deduced from their similarity indexes successfully delineated the species into their respective sections and the cultivars into their respective species. These markers have potential for application in fingerprinting, diversity studies and marker-assisted breeding of Lavandula.

  1. Annotated ESTs from various tissues of the brown planthopper Nilaparvata lugens: a genomic resource for studying agricultural pests.

    PubMed

    Noda, Hiroaki; Kawai, Sawako; Koizumi, Yoko; Matsui, Kageaki; Zhang, Qiang; Furukawa, Shigetoyo; Shimomura, Michihiko; Mita, Kazuei

    2008-03-03

    The brown planthopper (BPH), Nilaparvata lugens (Hemiptera, Delphacidae), is a serious insect pests of rice plants. Major means of BPH control are application of agricultural chemicals and cultivation of BPH resistant rice varieties. Nevertheless, BPH strains that are resistant to agricultural chemicals have developed, and BPH strains have appeared that are virulent against the resistant rice varieties. Expressed sequence tag (EST) analysis and related applications are useful to elucidate the mechanisms of resistance and virulence and to reveal physiological aspects of this non-model insect, with its poorly understood genetic background. More than 37,000 high-quality ESTs, excluding sequences of mitochondrial genome, microbial genomes, and rDNA, have been produced from 18 libraries of various BPH tissues and stages. About 10,200 clusters have been made from whole EST sequences, with average EST size of 627 bp. Among the top ten most abundantly expressed genes, three are unique and show no homology in BLAST searches. The actin gene was highly expressed in BPH, especially in the thorax. Tissue-specifically expressed genes were extracted based on the expression frequency among the libraries. An EST database is available at our web site. The EST library will provide useful information for transcriptional analyses, proteomic analyses, and gene functional analyses of BPH. Moreover, specific genes for hemimetabolous insects will be identified. The microarray fabricated based on the EST information will be useful for finding genes related to agricultural and biological problems related to this pest.

  2. Annotated ESTs from various tissues of the brown planthopper Nilaparvata lugens: A genomic resource for studying agricultural pests

    PubMed Central

    Noda, Hiroaki; Kawai, Sawako; Koizumi, Yoko; Matsui, Kageaki; Zhang, Qiang; Furukawa, Shigetoyo; Shimomura, Michihiko; Mita, Kazuei

    2008-01-01

    Background The brown planthopper (BPH), Nilaparvata lugens (Hemiptera, Delphacidae), is a serious insect pests of rice plants. Major means of BPH control are application of agricultural chemicals and cultivation of BPH resistant rice varieties. Nevertheless, BPH strains that are resistant to agricultural chemicals have developed, and BPH strains have appeared that are virulent against the resistant rice varieties. Expressed sequence tag (EST) analysis and related applications are useful to elucidate the mechanisms of resistance and virulence and to reveal physiological aspects of this non-model insect, with its poorly understood genetic background. Results More than 37,000 high-quality ESTs, excluding sequences of mitochondrial genome, microbial genomes, and rDNA, have been produced from 18 libraries of various BPH tissues and stages. About 10,200 clusters have been made from whole EST sequences, with average EST size of 627 bp. Among the top ten most abundantly expressed genes, three are unique and show no homology in BLAST searches. The actin gene was highly expressed in BPH, especially in the thorax. Tissue-specifically expressed genes were extracted based on the expression frequency among the libraries. An EST database is available at our web site. Conclusion The EST library will provide useful information for transcriptional analyses, proteomic analyses, and gene functional analyses of BPH. Moreover, specific genes for hemimetabolous insects will be identified. The microarray fabricated based on the EST information will be useful for finding genes related to agricultural and biological problems related to this pest. PMID:18315884

  3. Cross-comparison of diet quality indices for predicting chronic disease risk: findings from the Observation of Cardiovascular Risk Factors in Luxembourg (ORISCAV-LUX) study.

    PubMed

    Alkerwi, Ala'a; Vernier, Cédric; Crichton, Georgina E; Sauvageot, Nicolas; Shivappa, Nitin; Hébert, James R

    2015-01-28

    The scientific community has become increasingly interested in the overall quality of diets rather than in single food-based or single nutrient-based approaches to examine diet-disease relationships. Despite the plethora of indices used to measure diet quality, there still exist questions as to which of these can best predict health outcomes. The present study aimed to compare the ability of five diet quality indices, namely the Recommendation Compliance Index (RCI), Diet Quality Index-International (DQI-I), Dietary Approaches to Stop Hypertension (DASH), Mediterranean Diet Score (MDS), and Dietary Inflammatory Index (DII), to detect changes in chronic disease risk biomarkers. Nutritional data from 1352 participants, aged 18-69 years, of the Luxembourg nationwide cross-sectional ORISCAV-LUX (Observation of Cardiovascular Risk Factors in Luxembourg) study, 2007-8, were used to calculate adherence to the diet quality index. General linear modelling was performed to assess trends in biomarkers according to adherence to different dietary patterns, after adjustment for age, sex, education level, smoking status, physical activity and energy intake. Among the five selected diet quality indices, the MDS exhibited the best ability to detect changes in numerous risk markers and was significantly associated with lower levels of LDL-cholesterol, apo B, diastolic blood pressure, renal function indicators (creatinine and uric acid) and liver enzymes (serum γ-glutamyl-transpeptidase and glutamate-pyruvate transaminase). Compared with other dietary patterns, higher adherence to the Mediterranean diet is associated with a favourable cardiometabolic, hepatic and renal risk profile. Diets congruent with current universally accepted guidelines may be insufficient to prevent chronic diseases. Clinicians and public health decision makers should be aware of needs to improve the current dietary guidelines.

  4. Construction and application of EST library from Setaria italica in response to dehydration stress.

    PubMed

    Zhang, Jinpeng; Liu, Tingsong; Fu, Junjie; Zhu, Yun; Jia, Jinping; Zheng, Jun; Zhao, Yinhe; Zhang, Ying; Wang, Guoying

    2007-07-01

    Foxtail millet is a gramineous crop with low water requirement. Despite its high water use efficiency, less attention has been paid to the molecular genetics of foxtail millet. This article reports the construction of subtracted cDNA libraries from foxtail millet seedlings under dehydration stress and the expression profile analysis of 1947 UniESTs from the subtracted cDNA libraries by a cDNA microarray. The results showed that 95 and 57 ESTs were upregulated by dehydration stress, respectively, in roots and shoots of seedlings and that 10 and 27 ESTs were downregulated, respectively, in roots and shoots. The expression profile analysis showed that genes induced in foxtail millet roots were different from those in shoots during dehydration stress and that the early response to dehydration stress in foxtail millet roots was the activation of the glycolysis metabolism. Moreover, protein degradation pathway may also play a pivotal role in drought-tolerant responses of foxtail millet. Finally, Northern blot analysis validated well the cDNA microarray data.

  5. QuEST: Qualifying Environmentally Sustainable Technologies, Volume 5

    NASA Technical Reports Server (NTRS)

    Lewis, Pattie

    2010-01-01

    This edition of the QuEST newsletter contains brief articles that discuss the NASA Technology Evaluation for Environmental Risk Mitigation (TEERM) program, and the importance of collaboration, efforts in materials management and substitution for coatings for launch structures, Low volatile organic compound (VOC) Coatings Field Testing, Non-Chrome Coating Systems, Life Cycle Corrosion Testing, Lead-Free Electronics Testing and Corn Based Depainting and efforts in Pollution Control in the area of Hypergolic Propellant Destruction Evaluation, efforts in development of alternative energy in particular Hydrogen Sensors, Energy and Water Management, and efforts in remediation in the removal of Polychlorinated Biphenyl (PCB) contamination

  6. Consumption of ready-made meals and increased risk of obesity: findings from the Observation of Cardiovascular Risk Factors in Luxembourg (ORISCAV-LUX) study.

    PubMed

    Alkerwi, Ala'a; Crichton, Georgina E; Hébert, James R

    2015-01-28

    The consumption of ready-made meals, such as pre-packaged dishes, available at grocery stores and fast-food restaurants, is a habit related to our modern fast-paced lives. No study has examined the association of daily ready-made meal consumption with diet quality or health-related outcomes. The present study aimed to investigate the association between self-reported ready-made meal consumption and diet quality, as measured by compliance with dietary recommendations and with a set of adiposity measures, in a nationally representative sample of 1352 subjects, aged 18-69 years, participating in the nationwide population-based ORISCAV-LUX (Observation of Cardiovascular Risk Factors in Luxembourg) survey. The daily consumption of ready-made meals was calculated as follows: frequency of consumption × portion size × number of portions consumed. The sum of the daily consumption values of the eleven pre-packaged dishes included in the FFQ represented the total daily consumption of ready-made meals (g/d) for each participant. About 97% of the participants reported daily consumption of ready-made meals. The intake was highly prevalent in men living alone and varied according to education level. Ready-made meal consumption provided >7% of total daily energy. The fractions (%) of macro- and micronutrients derived from daily consumption of ready-made meals varied from 10% for total cholesterol to 0.65% for total fibre. Increased consumption of ready-made meals was found to be independently associated with abdominal obesity. On controlling for age, sex, socio-economic status and lifestyle factors, daily consumption of ready-made meals was found to be associated with higher energy intake and with poor compliance with national nutritional recommendations, and hence it could plausibly increase the risk of central obesity and fat deposition.

  7. Genetic diversity in the germplasm of black pepper determined by EST-SSR markers.

    PubMed

    Wu, B D; Fan, R; Hu, L S; Wu, H S; Hao, C Y

    2016-03-18

    This study aimed to assess genetic diversity in the germplasm of black pepper from around the world using SSR markers from EST. In total, 13 markers were selected and successfully amplified the target loci across the black pepper germplasm. All the EST-SSR markers showed high levels of polymorphisms with an average polymorphism information content of 0.93. The genetic similarity coefficients among all accessions ranged from 0.724 to 1.000, with an average of 0.867. These results indicated that black pepper germplasms possess a complex genetic background and high genetic diversity. Based on a cluster analysis, 148 black pepper germplasms were grouped in two major clades: the Neotropics and the Asian tropics. Peperomia pellucida was grouped separately and distantly from all other accessions. These results generally agreed with the genetic and geographic distances. However, the Asian tropics clade did not cluster according to their geographic origins. In addition, compared with the American accessions, the Asian wild accessions and cultivated accessions grouped together, indicating a close genetic relationship. This verified the origin of black pepper. The newly developed EST-SSRs are highly valuable resources for the conservation of black pepper germplasm diversity and for black pepper breeding.

  8. Acculturation, immigration status and cardiovascular risk factors among Portuguese immigrants to Luxembourg: findings from ORISCAV-LUX study.

    PubMed

    Alkerwi, Ala'a; Sauvageot, Nicolas; Pagny, Sybil; Beissel, Jean; Delagardelle, Charles; Lair, Marie-Lise

    2012-10-11

    No previous study has examined the prevalence of cardiovascular risk factors and explored the influence of immigration status and acculturation on overweight/obesity among the Portuguese immigrants to Luxembourg. Our objectives were to (1) compare the prevalence of cardiovascular risk factors between native Luxembourgers and Portuguese immigrants, (2) examine the relationship between immigrant generation status, proportion of life spent in Luxembourg and language proficiency or preference (as proxy variables of acculturation) and overweight/obesity among Portuguese immigrants, and (3) elucidate the role of underlying socioeconomic, behavioral and dietary factors in overweight/obesity differences among the two populations. Recent national cross-sectional data from ORISCAV-LUX survey 2007-2008, composed of 843 subjects were analyzed. Overweight/obesity was defined as body mass index (BMI) >25 kg/m(2). Acculturation score was measured by using immigrant generation status, proportion of life spent in Luxembourg, and language proficiency or preference. Univariable and multivariable logistic regression analyses were performed to examine the association between acculturation markers and overweight/obesity. Further, a series of successive models were fitted to explore the separated and added impact of potential mediators (socioeconomic status, physical activity, dietary factors) on overweight/obesity among Luxembourgers and Portuguese immigrants. Compared to Luxembourgers, Portuguese immigrants of first and second generation were younger and currently employed. About 68% of first generation Portuguese had only primary school, and about 44% were living below poverty threshold. Although the cardiovascular risk factors were comparable, Portuguese immigrants were more frequently overweight and obese than Luxembourgers, even after age and gender standardization to the European population. Overweight/obesity was significantly higher among Portuguese of first generation compared

  9. Expressed sequence tags (ESTs) from immune tissues of turbot (Scophthalmus maximus) challenged with pathogens

    PubMed Central

    Pardo, Belén G; Fernández, Carlos; Millán, Adrián; Bouza, Carmen; Vázquez-López, Araceli; Vera, Manuel; Alvarez-Dios, José A; Calaza, Manuel; Gómez-Tato, Antonio; Vázquez, María; Cabaleiro, Santiago; Magariños, Beatriz; Lemos, Manuel L; Leiro, José M; Martínez, Paulino

    2008-01-01

    Background The turbot (Scophthalmus maximus; Scophthalmidae; Pleuronectiformes) is a flatfish species of great relevance for marine aquaculture in Europe. In contrast to other cultured flatfish, very few genomic resources are available in this species. Aeromonas salmonicida and Philasterides dicentrarchi are two pathogens that affect turbot culture causing serious economic losses to the turbot industry. Little is known about the molecular mechanisms for disease resistance and host-pathogen interactions in this species. In this work, thousands of ESTs for functional genomic studies and potential markers linked to ESTs for mapping (microsatellites and single nucleotide polymorphisms (SNPs)) are provided. This information enabled us to obtain a preliminary view of regulated genes in response to these pathogens and it constitutes the basis for subsequent and more accurate microarray analysis. Results A total of 12584 cDNAs partially sequenced from three different cDNA libraries of turbot (Scophthalmus maximus) infected with Aeromonas salmonicida, Philasterides dicentrarchi and from healthy fish were analyzed. Three immune-relevant tissues (liver, spleen and head kidney) were sampled at several time points in the infection process for library construction. The sequences were processed into 9256 high-quality sequences, which constituted the source for the turbot EST database. Clustering and assembly of these sequences, revealed 3482 different putative transcripts, 1073 contigs and 2409 singletons. BLAST searches with public databases detected significant similarity (e-value ≤ 1e-5) in 1766 (50.7%) sequences and 816 of them (23.4%) could be functionally annotated. Two hundred three of these genes (24.9%), encoding for defence/immune-related proteins, were mostly identified for the first time in turbot. Some ESTs showed significant differences in the number of transcripts when comparing the three libraries, suggesting regulation in response to these pathogens. A total of

  10. Development and application of the RE-AIM QuEST mixed methods framework for program evaluation.

    PubMed

    Forman, Jane; Heisler, Michele; Damschroder, Laura J; Kaselitz, Elizabeth; Kerr, Eve A

    2017-06-01

    To increase the likelihood of successful implementation of interventions and promote dissemination across real-world settings, it is essential to evaluate outcomes related to dimensions other than Effectiveness alone. Glasgow and colleagues' RE-AIM framework specifies four additional types of outcomes that are important to decision-makers: Reach, Adoption, Implementation (including cost), and Maintenance. To further strengthen RE-AIM, we propose integrating qualitative assessments in an expanded framework: RE-AIM Qualitative Evaluation for Systematic Translation (RE-AIM QuEST), a mixed methods framework. RE-AIM QuEST guides formative evaluation to identify real-time implementation barriers and explain how implementation context may influence translation to additional settings. RE-AIM QuEST was used to evaluate a pharmacist-led hypertension management intervention at 3 VA facilities in 2008-2009. We systematically reviewed each of the five RE-AIM dimensions and created open-ended companion questions to quantitative measures and identified qualitative and quantitative data sources, measures, and analyses. To illustrate use of the RE-AIM QuEST framework, we provide examples of real-time, coordinated use of quantitative process measures and qualitative methods to identify site-specific issues, and retrospective use of these data sources and analyses to understand variation across sites and explain outcomes. For example, in the Reach dimension, we conducted real-time measurement of enrollment across sites and used qualitative data to better understand and address barriers at a low-enrollment site. The RE-AIM QuEST framework may be a useful tool for improving interventions in real-time, for understanding retrospectively why an intervention did or did not work, and for enhancing its sustainability and translation to other settings.

  11. Digital Pupillometry in Normal Subjects

    PubMed Central

    Rickmann, Annekatrin; Waizel, Maria; Kazerounian, Sara; Szurman, Peter; Wilhelm, Helmut; Boden, Karl T.

    2017-01-01

    ABSTRACT The aim of this study was to evaluate the pupil size of normal subjects at different illumination levels with a novel pupillometer. The pupil size of healthy study participants was measured with an infrared-video PupilX pupillometer (MEye Tech GmbH, Alsdorf, Germany) at five different illumination levels (0, 0.5, 4, 32, and 250 lux). Measurements were performed by the same investigator. Ninety images were executed during a measurement period of 3 seconds. The absolute linear camera resolution was approximately 20 pixels per mm. This cross-sectional study analysed 490 eyes of 245 subjects (mean age: 51.9 ± 18.3 years, range: 6–87 years). On average, pupil diameter decreased with increasing light intensities for both eyes, with a mean pupil diameter of 5.39 ± 1.04 mm at 0 lux, 5.20 ± 1.00 mm at 0.5 lux, 4.70 ± 0.97 mm at 4 lux, 3.74 ± 0.78 mm at 32 lux, and 2.84 ± 0.50 mm at 250 lux illumination. Furthermore, it was found that anisocoria increased by 0.03 mm per life decade for all illumination levels (R2 = 0.43). Anisocoria was higher under scotopic and mesopic conditions. This study provides additional information to the current knowledge concerning age- and light-related pupil size and anisocoria as a baseline for future patient studies. PMID:28228832

  12. Evidence for the generation of myristylated FMN by bacterial luciferase.

    PubMed

    Tabib, Chaitanya R; Brodl, Eveline; Macheroux, Peter

    2017-06-01

    The genes responsible for the light production in bioluminescent bacteria are present as an operon, luxCDABEG. Many strains of Photobacteria carry an additional gene, termed luxF. X-ray crystallographic analysis of LuxF revealed the presence of four molecules of a flavin derivative, i.e. 6-(3'-(R)-myristyl) flavin adenine mononucleotide (myrFMN) non-covalently bound to the homodimer. In the present study, we exploited the binding of myrFMN to recombinant apo-LuxF to explore the occurrence of myrFMN in various bioluminescent bacteria. MyrFMN was detected in all bacterial strains tested including Vibrio and Aliivibrio indicating that it is more widely occurring in bioluminescent bacteria than previously assumed. We also show that apo-LuxF captures myrFMN and thereby relieves the inhibitory effect on luciferase activity. Thus our results provide support for the hypothesis that LuxF acts as a scavenger of myrFMN in bioluminescent bacteria. However, the source of myrFMN remained obscure. To address this issue, we established a cofactor regeneration enzyme-catalyzed cascade reaction that supports luciferase activity in vitro for up to 3 days. This approach enabled us to unambiguously demonstrate that myrFMN is generated in the bacterial bioluminescent reaction. Based on this finding we postulate a reaction mechanism for myrFMN generation that is based on the luciferase reaction. © 2017 The Authors Molecular Microbiology Published by John Wiley & Sons Ltd.

  13. Differential transferability of EST-SSR primers developed from diploid species Pseudoroegneria spicata, Thinopyrum bessarabicum, and Th. elongatum

    USDA-ARS?s Scientific Manuscript database

    Simple sequence repeat technology based on expressed sequence tag (EST-SSR) is a useful genomic tool for genome mapping, characterizing plant species relationships, elucidating genome evolution, and tracing genes on alien chromosome segments. EST-SSR primers developed from three perennial diploid T...

  14. Use of Syntactic Elaboration Techniques to Enhance Comprehensibility of EST Texts

    ERIC Educational Resources Information Center

    Rahimi, Mohammad Ali; Rezaei, Amir

    2011-01-01

    The current study examined differential effects of two pre-modification types, syntactic elaboration and syntactic simplification (at the level of syntax and irrespective of problematic lexis), on EST students' reading comprehension. The purpose was to see whether a priori syntactic elaborative adjustment, given its advantages over simplification,…

  15. Performance of Arrowroot (Marantha arundinacea) in various light intensities

    NASA Astrophysics Data System (ADS)

    Oktafani, M. B.; Supriyono; Budiastuti, MTh S.; Purnomo, D.

    2018-03-01

    Arrowroot (Marantha arundinacea) is one of the potential food crops to support food security programs. Light intensity is one of the important factors for plant growth. Arrowroot cultivation technology still need further development. Traditionally, arrowroot grows wild under canopy without intentisification of cultivating which have low productivity. The purpose of research was to investigate the suitable light intensity for arrowroot. The experiment was conducted at Jumantono as Experimental Field of Faculty of Agricultural, University of Sebelas Maret Surakarta located in Karanganyar, from March to September 2016. The experiment used a complete randomized block design (CRBD) of light intensity level there are 27400 lux (full sun light), 18900 lux (shaded 31%), 13500 lux (shaded 51%) and 7400 lux (shaded 72%). Each treatment was replicated six times so there were 24 experimental units. The results showed that arrowroot is a low light adaptive plant. Arrowroot under the light intensity 7400 lux (27% full light), the number of leaves and tillers is not significantly different than under full light, although the plant is higher. The highest tuber diameter and length were 1.91 and 25.06 cm, respectively, and tuber weight reached 607.5-651.67 g per plant.

  16. Dim light at night increases body mass of female mice.

    PubMed

    Aubrecht, Taryn G; Jenkins, Richelle; Nelson, Randy J

    2015-05-01

    During the past century, the prevalence of light at night has increased in parallel with obesity rates. Dim light at night (dLAN) increases body mass in male mice. However, the effects of light at night on female body mass remain unspecified. Thus, female mice were exposed to a standard light/dark (LD; 16 h light at ∼150 lux/8 h dark at ∼0 lux) cycle or to light/dim light at night (dLAN; 16 h light at ∼150 lux/8 h dim light at ∼5 lux) cycles for six weeks. Females exposed to dLAN increased the rate of change in body mass compared to LD mice despite reduced total food intake during weeks five and six, suggesting that dLAN disrupted circadian rhythms resulting in deranged metabolism.

  17. Comprehensive EST analysis of the symbiotic sea anemone, Anemonia viridis

    PubMed Central

    Sabourault, Cécile; Ganot, Philippe; Deleury, Emeline; Allemand, Denis; Furla, Paola

    2009-01-01

    Background Coral reef ecosystems are renowned for their diversity and beauty. Their immense ecological success is due to a symbiotic association between cnidarian hosts and unicellular dinoflagellate algae, known as zooxanthellae. These algae are photosynthetic and the cnidarian-zooxanthellae association is based on nutritional exchanges. Maintenance of such an intimate cellular partnership involves many crosstalks between the partners. To better characterize symbiotic relationships between a cnidarian host and its dinoflagellate symbionts, we conducted a large-scale EST study on a symbiotic sea anemone, Anemonia viridis, in which the two tissue layers (epiderm and gastroderm) can be easily separated. Results A single cDNA library was constructed from symbiotic tissue of sea anemones A. viridis in various environmental conditions (both normal and stressed). We generated 39,939 high quality ESTs, which were assembled into 14,504 unique sequences (UniSeqs). Sequences were analysed and sorted according to their putative origin (animal, algal or bacterial). We identified many new repeated elements in the 3'UTR of most animal genes, suggesting that these elements potentially have a biological role, especially with respect to gene expression regulation. We identified genes of animal origin that have no homolog in the non-symbiotic starlet sea anemone Nematostella vectensis genome, but in other symbiotic cnidarians, and may therefore be involved in the symbiosis relationship in A. viridis. Comparison of protein domain occurrence in A. viridis with that in N. vectensis demonstrated an increase in abundance of some molecular functions, such as protein binding or antioxidant activity, suggesting that these functions are essential for the symbiotic state and may be specific adaptations. Conclusion This large dataset of sequences provides a valuable resource for future studies on symbiotic interactions in Cnidaria. The comparison with the closest available genome, the sea

  18. Development of New Candidate Gene and EST-Based Molecular Markers for Gossypium Species

    PubMed Central

    Buyyarapu, Ramesh; Kantety, Ramesh V.; Yu, John Z.; Saha, Sukumar; Sharma, Govind C.

    2011-01-01

    New source of molecular markers accelerate the efforts in improving cotton fiber traits and aid in developing high-density integrated genetic maps. We developed new markers based on candidate genes and G. arboreum EST sequences that were used for polymorphism detection followed by genetic and physical mapping. Nineteen gene-based markers were surveyed for polymorphism detection in 26 Gossypium species. Cluster analysis generated a phylogenetic tree with four major sub-clusters for 23 species while three species branched out individually. CAP method enhanced the rate of polymorphism of candidate gene-based markers between G. hirsutum and G. barbadense. Two hundred A-genome based SSR markers were designed after datamining of G. arboreum EST sequences (Mississippi Gossypium arboreum   EST-SSR: MGAES). Over 70% of MGAES markers successfully produced amplicons while 65 of them demonstrated polymorphism between the parents of G. hirsutum and G. barbadense RIL population and formed 14 linkage groups. Chromosomal localization of both candidate gene-based and MGAES markers was assisted by euploid and hypoaneuploid CS-B analysis. Gene-based and MGAES markers were highly informative as they were designed from candidate genes and fiber transcriptome with a potential to be integrated into the existing cotton genetic and physical maps. PMID:22315588

  19. The potential impact of animal protein intake on global and abdominal obesity: evidence from the Observation of Cardiovascular Risk Factors in Luxembourg (ORISCAV-LUX) study.

    PubMed

    Alkerwi, Ala'a; Sauvageot, Nicolas; Buckley, Jonathan D; Donneau, Anne-Françoise; Albert, Adelin; Guillaume, Michèle; Crichton, Georgina E

    2015-07-01

    To examine the association of total animal protein intake and protein derived from different dietary sources (meat; fish and shellfish; eggs; milk products) with global and abdominal obesity among adults in Luxembourg. Binary logistic regression analysis was used to assess the relationship between animal protein intake (as a percentage of total energy intake) and global obesity (BMI ≥ 30.0 kg/m(2)) and abdominal obesity (waist circumference ≥ 102 cm for men and ≥ 88 cm for women), after controlling for potential confounders. Observation of Cardiovascular Risk Factors in Luxembourg (ORISCAV-LUX) study. The study population was derived from a national cross-sectional stratified sample of 1152 individuals aged 18-69 years, recruited between November 2007 and January 2009. There was an independent positive association between total animal protein intake and both global (OR = 1.18; 95% CI 1.12, 1.25) and abdominal obesity (OR = 1.14; 95% CI 1.08, 1.20) after adjustment for age, gender, education, smoking, physical activity and intakes of total fat, carbohydrate, fibre, and fruit and vegetables. Protein intakes from meat, fish and shellfish were positively associated with global and abdominal obesity with further adjustment for vegetal protein and other sources of animal-derived protein (all P < 0.01). Protein derived from eggs or milk products was unrelated to global or abdominal obesity. Our findings suggest that protein derived from animal sources, in particular from meat, fish and shellfish, may be associated with increased risk of both global and abdominal obesity among presumably healthy adults in Luxembourg. These findings suggest that lower animal protein intakes may be important for maintenance of healthy body weight.

  20. Carboxylesterase Precursor (EST-1) Mediated the Fungicide Jinggangmycin-Suppressed Reproduction of Sogatella furcifera (Hemiptera: Delphacidae).

    PubMed

    Ge, Lin-Quan; Huang, Bo; Jiang, Yi-Ping; Gu, Hao-Tian; Xia, Ting; Yang, Guo-Qing; Liu, Fang; Wu, Jin-Cai

    2017-10-01

    The jinggangmycin (JGM) is a widely used fungicide for controlling the rice sheath blight, Rhizoctonia solani, in China. Previous experiments under lab conditions showed that JGM foliar spray suppressed Sogatella furcifera (Horvath) reproduction. However, the molecular mechanisms of JGM-driven changes in S. furcifera reproduction are unclear. Therefore, we selected carboxylesterase precursor (EST-1) as a target gene for silencing by RNAi based on gene expression profiles. The present results demonstrated that JGM and control + dsSfEST-1 treatments significantly reduced the number of eggs laid (down by 58% and 54%, respectively), oviposition period (down by 57% and 38%, respectively), and longevity (down by 32% and 38%, respectively) in adult females compared with untreated controls, while no pronounced differences in the preoviposition period were observed. Meanwhile, the dietary control + dsSfEST-1 treatment also severely impeded protein synthesis, specifically soluble ovarian protein content (down by 20% and 24%, respectively) and soluble sugar content (down by 42% and 35%, respectively), which led to stunted growth and reduced body weight in adult females. We thereby speculate that downregulated SfEST-1 expression may be one molecular mechanism underlying JGM-driven reproduction in S. furcifera. © The Author 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. The effect of bright light on lens compensation in chicks.

    PubMed

    Ashby, Regan S; Schaeffel, Frank

    2010-10-01

    It has been shown that sunlight or bright indoor light can inhibit the development of deprivation myopia in chicks. It remains unclear whether light merely acts on deprivation myopia or, more generally, modulates the rate of emmetropization and its set point. This study was conducted to test how bright light interacts with compensation for imposed optical defocus. Furthermore, a dopamine antagonist was applied to test whether the protective effect of light is mediated by dopamine. Experiment A: Chicks monocularly wore either -7 or +7 D lenses for a period of 5 days, either under normal laboratory illuminance (500 lux, n = 12 and 16, respectively) or under high ambient illuminance (15,000 lux, n = 12 and 16). Experiment B: Chicks wore diffusers for a period of 4 days, either under normal laboratory illuminance (500 lux, n = 9) or high ambient illuminance (15,000 lux), with the bright-light group intravitreally injected daily with either the dopamine D(2) antagonist spiperone (500 μM, n = 9) or a vehicle solution (0.1% ascorbic acid, n = 9), with an untreated group serving as the control (n = 6). Axial length and refraction were measured at the commencement and cessation of all treatments. Exposure to high illuminances (15,000 lux) for 5 hours per day significantly slowed compensation for negative lenses, compared with that seen under 500 lux, although full compensation was still achieved. Compensation for positive lenses was accelerated by exposure to high illuminances but, again, the end point refraction was unchanged, compared with that of the 500-lux group. High illuminance also reduced deprivation myopia by roughly 60%, compared with that seen under 500 lux. This protective effect was abolished, however, by the daily injection of spiperone, but was unaffected by the injection of a vehicle solution. High illuminance levels reduce the rate of compensation for negative lenses and enhance the rate for positive lenses, but do not change the set point of

  2. Prevalence and related risk factors of chronic kidney disease among adults in Luxembourg: evidence from the observation of cardiovascular risk factors (ORISCAV-LUX) study.

    PubMed

    Alkerwi, Ala'a; Sauvageot, Nicolas; El Bahi, Illiasse; Delagardelle, Charles; Beissel, Jean; Noppe, Stephanie; Roderick, Paul J; Mindell, Jennifer S; Stranges, Saverio

    2017-12-08

    Evidence on stages of renal impairment and related risk factors in Luxembourg is lacking. This study aimed to assess the prevalence of chronic kidney disease (CKD) and identify potential correlates among the general population, using the recent definition suggested by the Kidney Disease Improving Global Outcomes guidelines. Data analysed from 1361 participants aged 18-69 years, enrolled in the Observation of Cardiovascular Risk Factors in Luxembourg (ORISCAV-LUX) study, 2007-08. Descriptive and multivariable logistic regression analyses were performed to identify demographic, socio-economic, behavioural, and clinical factors associated with CKD, defined as a single estimated glomerular filtration rate (eGFR) measure <60 ml/min/1.73m 2 and/or urinary albumin: creatinine ratio (ACR) > 30 mg/g. Overall, 6.3% had CKD, including 4.4% and 0.7% with moderate and severe macroalbuminuria respectively. 0.1% had kidney failure (eGFR < 15 ml/min/1.73 m 2 ). CKD was higher among subjects with primary education and risk increased significantly with age; the odd ratio was more than 2-fold higher among participants aged 50-69 years. Hypertension and diabetes were associated with more than 3-fold and 4-fold higher risks of CKD [adjusted odd ratio (AOR 3.46 (95%CI 1.92, 6.24), P < 0.001] and [AOR 4.45 (2.18, 9.07), P < 0.001] respectively. Increased physical activity measured as total MET-hour/week was independently associated with a lower odds of CKD (P = 0.035). The national baseline prevalence estimate of CKD, a neglected public health problem, stresses the benefit of early detection particularly in high-risk subjects with associated cardiovascular pathologies (e.g. hypertension, diabetes), to prevent and defray costs related to eventual complications.

  3. PipeOnline 2.0: automated EST processing and functional data sorting.

    PubMed

    Ayoubi, Patricia; Jin, Xiaojing; Leite, Saul; Liu, Xianghui; Martajaja, Jeson; Abduraham, Abdurashid; Wan, Qiaolan; Yan, Wei; Misawa, Eduardo; Prade, Rolf A

    2002-11-01

    Expressed sequence tags (ESTs) are generated and deposited in the public domain, as redundant, unannotated, single-pass reactions, with virtually no biological content. PipeOnline automatically analyses and transforms large collections of raw DNA-sequence data from chromatograms or FASTA files by calling the quality of bases, screening and removing vector sequences, assembling and rewriting consensus sequences of redundant input files into a unigene EST data set and finally through translation, amino acid sequence similarity searches, annotation of public databases and functional data. PipeOnline generates an annotated database, retaining the processed unigene sequence, clone/file history, alignments with similar sequences, and proposed functional classification, if available. Functional annotation is automatic and based on a novel method that relies on homology of amino acid sequence multiplicity within GenBank records. Records are examined through a function ordered browser or keyword queries with automated export of results. PipeOnline offers customization for individual projects (MyPipeOnline), automated updating and alert service. PipeOnline is available at http://stress-genomics.org.

  4. Appraising the Early-est earthquake monitoring system for tsunami alerting at the Italian Candidate Tsunami Service Provider

    NASA Astrophysics Data System (ADS)

    Bernardi, F.; Lomax, A.; Michelini, A.; Lauciani, V.; Piatanesi, A.; Lorito, S.

    2015-09-01

    In this paper we present and discuss the performance of the procedure for earthquake location and characterization implemented in the Italian Candidate Tsunami Service Provider at the Istituto Nazionale di Geofisica e Vulcanologia (INGV) in Rome. Following the ICG/NEAMTWS guidelines, the first tsunami warning messages are based only on seismic information, i.e., epicenter location, hypocenter depth, and magnitude, which are automatically computed by the software Early-est. Early-est is a package for rapid location and seismic/tsunamigenic characterization of earthquakes. The Early-est software package operates using offline-event or continuous-real-time seismic waveform data to perform trace processing and picking, and, at a regular report interval, phase association, event detection, hypocenter location, and event characterization. Early-est also provides mb, Mwp, and Mwpd magnitude estimations. mb magnitudes are preferred for events with Mwp ≲ 5.8, while Mwpd estimations are valid for events with Mwp ≳ 7.2. In this paper we present the earthquake parameters computed by Early-est between the beginning of March 2012 and the end of December 2014 on a global scale for events with magnitude M ≥ 5.5, and we also present the detection timeline. We compare the earthquake parameters automatically computed by Early-est with the same parameters listed in reference catalogs. Such reference catalogs are manually revised/verified by scientists. The goal of this work is to test the accuracy and reliability of the fully automatic locations provided by Early-est. In our analysis, the epicenter location, hypocenter depth and magnitude parameters do not differ significantly from the values in the reference catalogs. Both mb and Mwp magnitudes show differences to the reference catalogs. We thus derived correction functions in order to minimize the differences and correct biases between our values and the ones from the reference catalogs. Correction of the Mwp

  5. Laryngoscope Illuminance in a Tertiary Care Medical Center: Industry Standards and Implications for Quality Laryngoscopy.

    PubMed

    Murphy, Michael K; Volsky, Peter G; Darrow, David H

    2015-11-01

    To test the hypothesis that a substantial proportion of laryngoscopes exhibit substandard illuminance by comparing laryngoscope illuminance in a tertiary-level medical center to established standards and identifying features associated with poor illuminance. Cross-sectional observational study. Academic tertiary care medical center (level 1 trauma center, specialty cardiac hospital, and general hospital). Laryngoscopes from main, cardiac, and outpatient operating rooms; emergency department; and code carts were tested using a standard technique. Illuminance (lux) was chosen as the outcome measure. Benchmarks were derived from the International Standards Organization and medical literature. Light types included incandescent bulb, light-emitting diode, and xenon. Personnel were surveyed regarding maintenance practices. Across all hospitals, 691 laryngoscopes were tested. Mean (SD) illuminance was 810 (700) lux for incandescent bulb-on-blade designs (n = 237), 1860 (1220) lux for incandescent bulb in-handle designs (n = 79), 4730 (3210) lux for LED (n = 354), and 28,800 (34,500) lux for xenon (n = 21). Seven percent of units failed to turn on (n = 45). Using an established threshold of 867 lux, 28% of devices (47% of incandescent, 12% of LED, and 10% of xenon) were substandard. All laryngoscopes were cleaned according to standard protocols following use; no preventive maintenance was reported. Twenty-eight percent of laryngoscopes in a tertiary care hospital exhibit substandard illuminance; these results corroborate the findings of our inaugural study on this subject. Consequently, our hospital is instituting changes to reduce the likelihood of substandard performance by laryngoscopes in circulation. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2015.

  6. Human phase response curve to a 1 h pulse of bright white light.

    PubMed

    St Hilaire, Melissa A; Gooley, Joshua J; Khalsa, Sat Bir S; Kronauer, Richard E; Czeisler, Charles A; Lockley, Steven W

    2012-07-01

    The phase resetting response of the human circadian pacemaker to light depends on the timing of exposure and is described by a phase response curve (PRC). The current study aimed to construct a PRC for a 1 h exposure to bright white light (∼8000 lux) and to compare this PRC to a <3 lux dim background light PRC. These data were also compared to a previously completed 6.7 h bright white light PRC and a <15 lux dim background light PRC constructed under similar conditions. Participants were randomized for exposure to 1 h of either bright white light (n=18) or <3 lux dim background light (n=18) scheduled at 1 of 18 circadian phases. Participants completed constant routine (CR) procedures in dim light (<3 lux) before and after the light exposure to assess circadian phase. Phase shifts were calculated as the difference in timing of dim light melatonin onset (DLMO) during pre- and post-stimulus CRs. Exposure to 1 h of bright white light induced a Type 1 PRC with a fitted peak-to-trough amplitude of 2.20 h. No discernible PRC was observed in the <3 lux dim background light PRC. The fitted peak-to-trough amplitude of the 1 h bright light PRC was ∼40% of that for the 6.7 h PRC despite representing only 15% of the light exposure duration, consistent with previous studies showing a non-linear duration–response function for the effects of light on circadian resetting.

  7. Quorum sensing is a key regulator for the antifungal and biocontrol activity of chitinase-producing Chromobacterium sp. C61.

    PubMed

    Kim, In Seon; Yang, Si Young; Park, Seur Kee; Kim, Young Cheol

    2017-01-01

    Chromobacterium sp. strain C61 has strong biocontrol activity; however, the genetic and biochemical determinants of its plant disease suppression activity are not well understood. Here, we report the identification and characterization of two new determinants of its biocontrol activity. Transposon mutagenesis was used to identify mutants that were deficient in fungal suppression. One of these mutants had an insertion in a homologue of depD, a structural gene in the dep operon, that encodes a protein involved in non-ribosomal peptide synthesis. In the second mutant, the insertion was in a homologue of the luxI gene, which encodes a homoserine lactone synthase. The luxI - and depD - mutants had no antifungal activity in vitro and a dramatically reduced capacity to suppress various plant diseases in planta. Antifungal production and biocontrol were restored by complementation of the luxI - mutant. Other phenotypes associated with effective biological control, including motility and lytic enzyme secretion, were also affected by the luxI mutation. Biochemical analysis of ethyl acetate extracts of culture filtrates of the mutant and wild-type strains showed that a key antifungal compound, chromobactomycin, was produced by wild-type C61 and the complemented luxI - mutant, but not by the luxI - or depD - mutant. These data suggest that multiple biocontrol-related phenotypes are regulated by homoserine lactones in C61. Thus, quorum sensing plays an essential role in the biological control potential of diverse bacterial lineages. © 2016 BSPP and John Wiley & Sons Ltd.

  8. Human phase response curve to a 1 h pulse of bright white light

    PubMed Central

    St Hilaire, Melissa A; Gooley, Joshua J; Khalsa, Sat Bir S; Kronauer, Richard E; Czeisler, Charles A; Lockley, Steven W

    2012-01-01

    The phase resetting response of the human circadian pacemaker to light depends on the timing of exposure and is described by a phase response curve (PRC). The current study aimed to construct a PRC for a 1 h exposure to bright white light (∼8000 lux) and to compare this PRC to a <3 lux dim background light PRC. These data were also compared to a previously completed 6.7 h bright white light PRC and a <15 lux dim background light PRC constructed under similar conditions. Participants were randomized for exposure to 1 h of either bright white light (n= 18) or <3 lux dim background light (n= 18) scheduled at 1 of 18 circadian phases. Participants completed constant routine (CR) procedures in dim light (<3 lux) before and after the light exposure to assess circadian phase. Phase shifts were calculated as the difference in timing of dim light melatonin onset (DLMO) during pre- and post-stimulus CRs. Exposure to 1 h of bright white light induced a Type 1 PRC with a fitted peak-to-trough amplitude of 2.20 h. No discernible PRC was observed in the <3 lux dim background light PRC. The fitted peak-to-trough amplitude of the 1 h bright light PRC was ∼40% of that for the 6.7 h PRC despite representing only 15% of the light exposure duration, consistent with previous studies showing a non-linear duration–response function for the effects of light on circadian resetting. PMID:22547633

  9. In-space assembly and servicing infrastructures for the Evolvable Space Telescope (EST)

    NASA Astrophysics Data System (ADS)

    Lillie, Charles F.; MacEwen, Howard A.

    2016-07-01

    The concept for EST presented in past SPIE forums will benefit significantly from the current efforts of DARPA, NASA and several commercial organizations to develop an in-space infrastructure that will enable on-orbit assembly, servicing, repair and repurposing of space vehicles. Two documents provide particularly relevant discussions: "NASA's Journey to Mars: Pioneering Next Steps in Space Exploration" provides a recent (2015) outline of NASA's thoughts on human deep space exploration and the tools that will enable it, while the "On-Orbit Satellite Servicing Study: Project Report" details a number of the concepts and technologies that must be developed. In this paper we examine the concepts in these and related documents to explore how systems such as EST will shape and support the infrastructure needed by future space vehicles. In so doing, we address previous examples of on-orbit assembly and servicing of space vehicles; the lessons learned from these efforts and the existing systems and facilities available to execute servicing missions; the EST concept for an LUVOIR telescope designed for in-orbit assembly and servicing and the resulting requirements for a servicing vehicle; the use of heavy lift launch vehicles, including the SLS and Exploration Upper Stage to co-manifest other large payloads along with a crewed Orion mission; Deep Space Habitats (DSHs) in cislunar space as a site for assembly and servicing spacecraft vehicles, and a base for Maneuverable Servicing Vehicles; and how space vehicles need to be designed for in-space assembly and servicing (i.e., commonality of parts, systems, modularity, accessibility, and stable maneuverability).

  10. DoEstRare: A statistical test to identify local enrichments in rare genomic variants associated with disease.

    PubMed

    Persyn, Elodie; Karakachoff, Matilde; Le Scouarnec, Solena; Le Clézio, Camille; Campion, Dominique; Consortium, French Exome; Schott, Jean-Jacques; Redon, Richard; Bellanger, Lise; Dina, Christian

    2017-01-01

    Next-generation sequencing technologies made it possible to assay the effect of rare variants on complex diseases. As an extension of the "common disease-common variant" paradigm, rare variant studies are necessary to get a more complete insight into the genetic architecture of human traits. Association studies of these rare variations show new challenges in terms of statistical analysis. Due to their low frequency, rare variants must be tested by groups. This approach is then hindered by the fact that an unknown proportion of the variants could be neutral. The risk level of a rare variation may be determined by its impact but also by its position in the protein sequence. More generally, the molecular mechanisms underlying the disease architecture may involve specific protein domains or inter-genic regulatory regions. While a large variety of methods are optimizing functionality weights for each single marker, few evaluate variant position differences between cases and controls. Here, we propose a test called DoEstRare, which aims to simultaneously detect clusters of disease risk variants and global allele frequency differences in genomic regions. This test estimates, for cases and controls, variant position densities in the genetic region by a kernel method, weighted by a function of allele frequencies. We compared DoEstRare with previously published strategies through simulation studies as well as re-analysis of real datasets. Based on simulation under various scenarios, DoEstRare was the sole to consistently show highest performance, in terms of type I error and power both when variants were clustered or not. DoEstRare was also applied to Brugada syndrome and early-onset Alzheimer's disease data and provided complementary results to other existing tests. DoEstRare, by integrating variant position information, gives new opportunities to explain disease susceptibility. DoEstRare is implemented in a user-friendly R package.

  11. Environmental and Sustainable Technology Evaluations (ESTE): Verification of Microbial Resistant Building Materials

    EPA Science Inventory

    This is an ESTE project summary brief. Many of the finished interior surfaces of homes and buildings are composed of materials that are prone to mold growth. These surfaces include gypsum board, wood flooring, insulation, and components of the heating and air conditioning system...

  12. Effects of blue light on pigment biosynthesis of Monascus.

    PubMed

    Chen, Di; Xue, Chunmao; Chen, Mianhua; Wu, Shufen; Li, Zhenjing; Wang, Changlu

    2016-04-01

    The influence of different illumination levels of blue light on the growth and intracellular pigment yields of Monascus strain M9 was investigated. Compared with darkness, constant exposure to blue light of 100 lux reduced the yields of six pigments, namely, rubropunctatamine (RUM), monascorubramine (MOM), rubropunctatin (RUN), monascorubrin (MON), monascin (MS), and ankaflavin (AK). However, exposure to varying levels of blue light had different effects on pigment production. Exposure to 100 lux of blue light once for 30 min/day and to 100 lux of blue light once and twice for 15 min/day could enhance RUM, MOM, MS, and AK production and reduce RUN and MON compared with non-exposure. Exposure to 100 lux twice for 30 min/day and to 200 lux once for 45 min/day decreased the RUM, MOM, MS, and AK yields and increased the RUN and MON. Meanwhile, the expression levels of pigment biosynthetic genes were analyzed by real-time quantitative PCR. Results indicated that gene MpPKS5, mppR1, mppA, mppB, mmpC, mppD, MpFasA, MpFasB, and mppF were positively correlated with the yields of RUN and MON, whereas mppE and mppR2 were associated with RUM, MOM, MS, and AK production.

  13. Are luminescent bacteria suitable for online detection and monitoring of toxic compounds in drinking water and its sources?

    PubMed

    Woutersen, Marjolijn; Belkin, Shimshon; Brouwer, Bram; van Wezel, Annemarie P; Heringa, Minne B

    2011-05-01

    Biosensors based on luminescent bacteria may be valuable tools to monitor the chemical quality and safety of surface and drinking water. In this review, an overview is presented of the recombinant strains available that harbour the bacterial luciferase genes luxCDABE, and which may be used in an online biosensor for water quality monitoring. Many bacterial strains have been described for the detection of a broad range of toxicity parameters, including DNA damage, protein damage, membrane damage, oxidative stress, organic pollutants, and heavy metals. Most lux strains have sensitivities with detection limits ranging from milligrams per litre to micrograms per litre, usually with higher sensitivities in compound-specific strains. Although the sensitivity of lux strains can be enhanced by various molecular manipulations, most reported detection thresholds are still too high to detect levels of individual contaminants as they occur nowadays in European drinking waters. However, lux strains sensing specific toxic effects have the advantage of being able to respond to mixtures of contaminants inducing the same effect, and thus could be used as a sensor for the sum effect, including the effect of compounds that are as yet not identified by chemical analysis. An evaluation of the suitability of lux strains for monitoring surface and drinking water is therefore provided.

  14. Dose-response relationship for light intensity and ocular and electroencephalographic correlates of human alertness

    NASA Technical Reports Server (NTRS)

    Cajochen, C.; Zeitzer, J. M.; Czeisler, C. A.; Dijk, D. J.

    2000-01-01

    Light can elicit both circadian and acute physiological responses in humans. In a dose response protocol men and women were exposed to illuminances ranging from 3 to 9100 lux for 6.5 h during the early biological night after they had been exposed to <3 lux for several hours. Light exerted an acute alerting response as assessed by a reduction in the incidence of slow-eye movements, a reduction of EEG activity in the theta-alpha frequencies (power density in the 5-9 Hz range) as well as a reduction in self-reported sleepiness. This alerting response was positively correlated with the degree of melatonin suppression by light. In accordance with the dose response function for circadian resetting and melatonin suppression, the responses of all three indices of alertness to variations in illuminance were consistent with a logistic dose response curve. Half of the maximum alerting response to bright light of 9100 lux was obtained with room light of approximately 100 lux. This sensitivity to light indicates that variations in illuminance within the range of typical, ambient, room light (90-180 lux) can have a significant impact on subjective alertness and its electrophysiologic concomitants in humans during the early biological night.

  15. Isolation and characterization of novel EST-derived genic markers in Pisum sativum (Fabaceae)1

    PubMed Central

    Jain, Shalu; McPhee, Kevin E.

    2013-01-01

    • Premise of the study: Novel markers were developed for pea (Pisum sativum) from pea expressed sequence tags (ESTs) having significant homology to Medicago truncatula gene sequences to investigate genetic diversity, linkage mapping, and cross-species transferability. • Methods and Results: Seventy-seven EST-derived genic markers were developed through comparative mapping between M. truncatula and P. sativum in which 75 markers produced PCR products and 33 were polymorphic among 16 pea genotypes. • Conclusions: The novel markers described here will be useful for future genetic studies of P. sativum; their amplification in lentil (Lens culinaris) demonstrates their potential for use in closely related species. PMID:25202494

  16. The effect of ambient illuminance on the development of deprivation myopia in chicks.

    PubMed

    Ashby, Regan; Ohlendorf, Arne; Schaeffel, Frank

    2009-11-01

    Recent epidemiologic studies have shown that children who spend a higher proportion of time outdoors are less likely to develop myopia. This study was undertaken to investigate whether light levels may be a relevant factor in the development of myopia. METHODS; Paradigm 1: Chicks were fitted with translucent diffusers for 5 days, with the diffusers removed daily for 15 minutes under one of three lighting conditions: (1) normal laboratory lighting (500 lux), (2) intense laboratory lighting (15,000 lux), or (3) daylight (30,000 lux). A control group, which continuously wore diffusers, was also kept under an illumination of 500 lux. Paradigm 2: Chicks fitted with translucent diffusers were raised for 4 days under one of three lighting conditions: (1) low laboratory lighting (50 lux, n = 9), (2) normal laboratory lighting (500 lux, n = 18), or (3) intense laboratory lights (15,000 lux, n = 9). In groups 1 and 3, the chicks were exposed to either low or high ambient illuminances for a period of 6 hours per day (10 AM-4 PM), but were kept under 500 lux for the remaining time of the light phase. Axial length and refraction were measured at the commencement and cessation of all treatments, with corneal curvature measured additionally in paradigm 2. Paradigm 1: The chicks exposed daily to sunlight for 15 minutes had significantly shorter eyes (8.81 +/- 0.05 mm; P < 0.01) and less myopic refractions (-1.1 +/- 0.45 D; P < 0.01) than did the chicks that had their diffusers removed under normal laboratory light levels (8.98 +/- 0.03 mm, -5.3 +/- 0.5 D). If the diffusers were removed under intense laboratory lights, the chicks also developed shorter eyes (8.88 +/- 0.04 mm; P < 0.01) and less myopic refractions (-3.4 +/- 0.6D; P < 0.01). Paradigm 2: The chicks that wore diffusers continuously under high illuminance had shorter eyes (8.54 +/- 0.02 mm; P < 0.01) and less myopic refractions (+0.04 +/- 0.7D; P < 0.001) compared with those chicks reared under normal light levels (8

  17. Acculturation, immigration status and cardiovascular risk factors among Portuguese immigrants to Luxembourg: findings from ORISCAV-LUX study

    PubMed Central

    2012-01-01

    Background No previous study has examined the prevalence of cardiovascular risk factors and explored the influence of immigration status and acculturation on overweight/obesity among the Portuguese immigrants to Luxembourg. Our objectives were to (1) compare the prevalence of cardiovascular risk factors between native Luxembourgers and Portuguese immigrants, (2) examine the relationship between immigrant generation status, proportion of life spent in Luxembourg and language proficiency or preference (as proxy variables of acculturation) and overweight/obesity among Portuguese immigrants, and (3) elucidate the role of underlying socioeconomic, behavioral and dietary factors in overweight/obesity differences among the two populations. Methods Recent national cross-sectional data from ORISCAV-LUX survey 2007–2008, composed of 843 subjects were analyzed. Overweight/obesity was defined as body mass index (BMI) >25kg/m2. Acculturation score was measured by using immigrant generation status, proportion of life spent in Luxembourg, and language proficiency or preference. Univariable and multivariable logistic regression analyses were performed to examine the association between acculturation markers and overweight/obesity. Further, a series of successive models were fitted to explore the separated and added impact of potential mediators (socioeconomic status, physical activity, dietary factors) on overweight/obesity among Luxembourgers and Portuguese immigrants. Results Compared to Luxembourgers, Portuguese immigrants of first and second generation were younger and currently employed. About 68% of first generation Portuguese had only primary school, and about 44% were living below poverty threshold. Although the cardiovascular risk factors were comparable, Portuguese immigrants were more frequently overweight and obese than Luxembourgers, even after age and gender standardization to the European population. Overweight/obesity was significantly higher among Portuguese of

  18. Flexibility and Stability Trade-Off in Active Site of Cold-Adapted Pseudomonas mandelii Esterase EstK.

    PubMed

    Truongvan, Ngoc; Jang, Sei-Heon; Lee, ChangWoo

    2016-06-28

    Cold-adapted enzymes exhibit enhanced conformational flexibility, especially in their active sites, as compared with their warmer-temperature counterparts. However, the mechanism by which cold-adapted enzymes maintain their active site stability is largely unknown. In this study, we investigated the role of conserved D308-Y309 residues located in the same loop as the catalytic H307 residue in the cold-adapted esterase EstK from Pseudomonas mandelii. Mutation of D308 and/or Y309 to Ala or deletion resulted in increased conformational flexibility. Particularly, the D308A or Y309A mutant showed enhanced substrate affinity and catalytic rate, as compared with wild-type EstK, via enlargement of the active site. However, all mutant EstK enzymes exhibited reduced thermal stability. The effect of mutation was greater for D308 than Y309. These results indicate that D308 is not preferable for substrate selection and catalytic activity, whereas hydrogen bond formation involving D308 is critical for active site stabilization. Taken together, conformation of the EstK active site is constrained via flexibility-stability trade-off for enzyme catalysis and thermal stability. Our study provides further insights into active site stabilization of cold-adapted enzymes.

  19. Sequence analysis reveals genomic factors affecting EST-SSR primer performance and polymorphism

    USDA-ARS?s Scientific Manuscript database

    Search for simple sequence repeat (SSR) motifs and design of flanking primers in expressed sequence tag (EST) sequences can be easily done at a large scale using bioinformatics programs. However, failed amplification and/or detection, along with lack of polymorphism, is often seen among randomly sel...

  20. Gene discovery using massively parallel pyrosequencing to develop ESTs for the flesh fly Sarcophaga crassipalpis

    PubMed Central

    Hahn, Daniel A; Ragland, Gregory J; Shoemaker, D DeWayne; Denlinger, David L

    2009-01-01

    Background Flesh flies in the genus Sarcophaga are important models for investigating endocrinology, diapause, cold hardiness, reproduction, and immunity. Despite the prominence of Sarcophaga flesh flies as models for insect physiology and biochemistry, and in forensic studies, little genomic or transcriptomic data are available for members of this genus. We used massively parallel pyrosequencing on the Roche 454-FLX platform to produce a substantial EST dataset for the flesh fly Sarcophaga crassipalpis. To maximize sequence diversity, we pooled RNA extracted from whole bodies of all life stages and normalized the cDNA pool after reverse transcription. Results We obtained 207,110 ESTs with an average read length of 241 bp. These reads assembled into 20,995 contigs and 31,056 singletons. Using BLAST searches of the NR and NT databases we were able to identify 11,757 unique gene elements (E<0.0001) representing approximately 9,000 independent transcripts. Comparison of the distribution of S. crassipalpis unigenes among GO Biological Process functional groups with that of the Drosophila melanogaster transcriptome suggests that our ESTs are broadly representative of the flesh fly transcriptome. Insertion and deletion errors in 454 sequencing present a serious hurdle to comparative transcriptome analysis. Aided by a new approach to correcting for these errors, we performed a comparative analysis of genetic divergence across GO categories among S. crassipalpis, D. melanogaster, and Anopheles gambiae. The results suggest that non-synonymous substitutions occur at similar rates across categories, although genes related to response to stimuli may evolve slightly faster. In addition, we identified over 500 potential microsatellite loci and more than 12,000 SNPs among our ESTs. Conclusion Our data provides the first large-scale EST-project for flesh flies, a much-needed resource for exploring this model species. In addition, we identified a large number of potential

  1. Artificially Constructed Quorum-Sensing Circuits Are Used for Subtle Control of Bacterial Population Density

    PubMed Central

    Wang, Zhaoshou; Wu, Xin; Peng, Jianghai; Hu, Yidan; Fang, Baishan; Huang, Shiyang

    2014-01-01

    Vibrio fischeri is a typical quorum-sensing bacterium for which lux box, luxR, and luxI have been identified as the key elements involved in quorum sensing. To decode the quorum-sensing mechanism, an artificially constructed cell–cell communication system has been built. In brief, the system expresses several programmed cell-death BioBricks and quorum-sensing genes driven by the promoters lux pR and PlacO-1 in Escherichia coli cells. Their transformation and expression was confirmed by gel electrophoresis and sequencing. To evaluate its performance, viable cell numbers at various time periods were investigated. Our results showed that bacteria expressing killer proteins corresponding to ribosome binding site efficiency of 0.07, 0.3, 0.6, or 1.0 successfully sensed each other in a population-dependent manner and communicated with each other to subtly control their population density. This was also validated using a proposed simple mathematical model. PMID:25119347

  2. Genetic labelling and application of the isoproturon-mineralizing Sphingomonas sp. strain SRS2 in soil and rhizosphere.

    PubMed

    Kristensen, K E; Jacobsen, C S; Hansen, L H; Aamand, J; Morgan, J A W; Sternberg, C; Sørensen, S R

    2006-09-01

    To construct a luxAB-labelled Sphingomonas sp. strain SRS2 maintaining the ability to mineralize the herbicide isoproturon and usable for monitoring the survival and distribution of strain SRS2 on plant roots in laboratory systems. We inserted the mini-Tn5-luxAB marker into strain SRS2 using conjugational mating. In the transconjugant mutants luciferase was produced in varying levels. The mutants showed significant differences in their ability to degrade isoproturon. One luxAB-labelled mutant maintained the ability to mineralize isoproturon and was therefore selected for monitoring colonization of barley roots. We successfully constructed a genetically labelled isoproturon-mineralizing-strain SRS2 and demonstrated its ability to survive in soil and its colonization of rhizosphere. The construction of a luxAB-labelled strain SRS2 maintaining the degradative ability, provides a powerful tool for ecological studies serving as the basis for evaluating SRS2 as a bioremediation agent.

  3. The first set of EST resource for gene discovery and marker development in pigeonpea (Cajanus cajan L.).

    PubMed

    Raju, Nikku L; Gnanesh, Belaghihalli N; Lekha, Pazhamala; Jayashree, Balaji; Pande, Suresh; Hiremath, Pavana J; Byregowda, Munishamappa; Singh, Nagendra K; Varshney, Rajeev K

    2010-03-11

    Pigeonpea (Cajanus cajan (L.) Millsp) is one of the major grain legume crops of the tropics and subtropics, but biotic stresses [Fusarium wilt (FW), sterility mosaic disease (SMD), etc.] are serious challenges for sustainable crop production. Modern genomic tools such as molecular markers and candidate genes associated with resistance to these stresses offer the possibility of facilitating pigeonpea breeding for improving biotic stress resistance. Availability of limited genomic resources, however, is a serious bottleneck to undertake molecular breeding in pigeonpea to develop superior genotypes with enhanced resistance to above mentioned biotic stresses. With an objective of enhancing genomic resources in pigeonpea, this study reports generation and analysis of comprehensive resource of FW- and SMD- responsive expressed sequence tags (ESTs). A total of 16 cDNA libraries were constructed from four pigeonpea genotypes that are resistant and susceptible to FW ('ICPL 20102' and 'ICP 2376') and SMD ('ICP 7035' and 'TTB 7') and a total of 9,888 (9,468 high quality) ESTs were generated and deposited in dbEST of GenBank under accession numbers GR463974 to GR473857 and GR958228 to GR958231. Clustering and assembly analyses of these ESTs resulted into 4,557 unique sequences (unigenes) including 697 contigs and 3,860 singletons. BLASTN analysis of 4,557 unigenes showed a significant identity with ESTs of different legumes (23.2-60.3%), rice (28.3%), Arabidopsis (33.7%) and poplar (35.4%). As expected, pigeonpea ESTs are more closely related to soybean (60.3%) and cowpea ESTs (43.6%) than other plant ESTs. Similarly, BLASTX similarity results showed that only 1,603 (35.1%) out of 4,557 total unigenes correspond to known proteins in the UniProt database (

  4. The first set of EST resource for gene discovery and marker development in pigeonpea (Cajanus cajan L.)

    PubMed Central

    2010-01-01

    Background Pigeonpea (Cajanus cajan (L.) Millsp) is one of the major grain legume crops of the tropics and subtropics, but biotic stresses [Fusarium wilt (FW), sterility mosaic disease (SMD), etc.] are serious challenges for sustainable crop production. Modern genomic tools such as molecular markers and candidate genes associated with resistance to these stresses offer the possibility of facilitating pigeonpea breeding for improving biotic stress resistance. Availability of limited genomic resources, however, is a serious bottleneck to undertake molecular breeding in pigeonpea to develop superior genotypes with enhanced resistance to above mentioned biotic stresses. With an objective of enhancing genomic resources in pigeonpea, this study reports generation and analysis of comprehensive resource of FW- and SMD- responsive expressed sequence tags (ESTs). Results A total of 16 cDNA libraries were constructed from four pigeonpea genotypes that are resistant and susceptible to FW ('ICPL 20102' and 'ICP 2376') and SMD ('ICP 7035' and 'TTB 7') and a total of 9,888 (9,468 high quality) ESTs were generated and deposited in dbEST of GenBank under accession numbers GR463974 to GR473857 and GR958228 to GR958231. Clustering and assembly analyses of these ESTs resulted into 4,557 unique sequences (unigenes) including 697 contigs and 3,860 singletons. BLASTN analysis of 4,557 unigenes showed a significant identity with ESTs of different legumes (23.2-60.3%), rice (28.3%), Arabidopsis (33.7%) and poplar (35.4%). As expected, pigeonpea ESTs are more closely related to soybean (60.3%) and cowpea ESTs (43.6%) than other plant ESTs. Similarly, BLASTX similarity results showed that only 1,603 (35.1%) out of 4,557 total unigenes correspond to known proteins in the UniProt database (≤ 1E-08). Functional categorization of the annotated unigenes sequences showed that 153 (3.3%) genes were assigned to cellular component category, 132 (2.8%) to biological process, and 132 (2.8%) in

  5. AntiHunter 2.0: increased speed and sensitivity in searching BLAST output for EST antisense transcripts.

    PubMed

    Lavorgna, Giovanni; Triunfo, Riccardo; Santoni, Federico; Orfanelli, Ugo; Noci, Sara; Bulfone, Alessandro; Zanetti, Gianluigi; Casari, Giorgio

    2005-07-01

    An increasing number of eukaryotic and prokaryotic genes are being found to have natural antisense transcripts (NATs). There is also growing evidence to suggest that antisense transcription could play a key role in many human diseases. Consequently, there have been several recent attempts to set up computational procedures aimed at identifying novel NATs. Our group has developed the AntiHunter program for the identification of expressed sequence tag (EST) antisense transcripts from BLAST output. In order to perform an analysis, the program requires a genomic sequence plus an associated list of transcript names and coordinates of the genomic region. After masking the repeated regions, the program carries out a BLASTN search of this sequence in the selected EST database, reporting via email the EST entries that reveal an antisense transcript according to the user-supplied list. Here, we present the newly developed version 2.0 of the AntiHunter tool. Several improvements have been added to this version of the program in order to increase its ability to detect a larger number of antisense ESTs. As a result, AntiHunter can now detect, on average, >45% more antisense ESTs with little or no increase in the percentage of the false positives. We also raised the maximum query size to 3 Mb (previously 1 Mb). Moreover, we found that a reasonable trade-off between the program search sensitivity and the maximum allowed size of the input-query sequence could be obtained by querying the database with the MEGABLAST program, rather than by using the BLAST one. We now offer this new opportunity to users, i.e. if choosing the MEGABLAST option, users can input a query sequence up to 30 Mb long, thus considerably improving the possibility to analyze longer query regions. The AntiHunter tool is freely available at http://bioinfo.crs4.it/AH2.0.

  6. Use of Glycerol as an Optical Clearing Agent for Enhancing Photonic Transference and Detection of Salmonella typhimurium through Porcine Skin

    USDA-ARS?s Scientific Manuscript database

    The objective of this study was to evaluate glycerol (GLY) and GLY + dimethyl sulfoxide (DMSO) to increase photonic detection of transformed Salmonella typhimurium (S. typh-lux) through porcine skin. Skin was placed on 96-well plates containing S. typh-lux, imaged (5 min) using a CCD camera, and the...

  7. Use of Glycerol as an Optical Clearing Agent for Enhancing Photonic Transference and Detection of Salmonella typhimurium Through Porcine Skin

    USDA-ARS?s Scientific Manuscript database

    The objective of this study was to evaluate glycerol (GLY) and GLY + dimethyl sulfoxide (DMSO) to increase photonic detection of transformed Salmonella typhimurium (S. typh-lux) through porcine skin. Skin was placed on 96-well plates containing S. typh-lux, imaged (5 min) using a CCD camera, and the...

  8. Saturation mutagenesis of a CepR binding site as a means to identify new quorum-regulated promoters in Burkholderia cenocepacia

    USDA-ARS?s Scientific Manuscript database

    Burkholderia cenocepacia, an opportunistic pathogen of humans, encodes the CepI and CepR proteins, which resemble the LuxI and LuxR quorum sensing proteins of Vibrio fischeri. CepI directs the synthesis of octanoylhomoserine lactone (OHL), while CepR is an OHL dependent transcription factor. In pr...

  9. Development and Characterization of 18 Novel EST-SSRs from the Western Flower Thrips, Frankliniella occidentalis (Pergande)

    PubMed Central

    Yang, Xian-Ming; Sun, Jing-Tao; Xue, Xiao-Feng; Zhu, Wen-Chao; Hong, Xiao-Yue

    2012-01-01

    The western flower thrips, Frankliniella occidentalis (Pergande), is an invasive species and the most economically important pest within the insect order Thysanoptera. For a better understanding of the genetic makeup and migration patterns of F. occidentalis throughout the world, we characterized 18 novel polymorphic EST-derived microsatellites. The mutational mechanism of these EST-SSRs was also investigated to facilitate the selection of appropriate combinations of markers for population genetic studies. Genetic diversity of these novel markers was assessed in 96 individuals from three populations in China (Harbin, Dali, and Guiyang). The results showed that all these 18 loci were highly polymorphic; the number of alleles ranged from 2 to 15, with an average of 5.50 alleles per locus. The observed (HO) and expected (HE) heterozygosities ranged from 0.072 to 0.707 and 0.089 to 0.851, respectively. Furthermore, only two locus/population combinations (WFT144 in Dali and WFT50 in Guiyang) significantly deviated from Hardy–Weinberg equilibrium (HWE). Pairwise FST analysis showed a low but significant differentiation (0.026 < FST < 0.032) among all three pairwise population comparisons. Sequence analysis of alleles per locus revealed a complex mutational pattern of these EST-SSRs. Thus, these EST-SSRs are useful markers but greater attention should be paid to the mutational characteristics of these microsatellites when they are used in population genetic studies. PMID:22489130

  10. Development and characterization of 18 novel EST-SSRs from the western flower Thrips, Frankliniella occidentalis (Pergande).

    PubMed

    Yang, Xian-Ming; Sun, Jing-Tao; Xue, Xiao-Feng; Zhu, Wen-Chao; Hong, Xiao-Yue

    2012-01-01

    The western flower thrips, Frankliniella occidentalis (Pergande), is an invasive species and the most economically important pest within the insect order Thysanoptera. For a better understanding of the genetic makeup and migration patterns of F. occidentalis throughout the world, we characterized 18 novel polymorphic EST-derived microsatellites. The mutational mechanism of these EST-SSRs was also investigated to facilitate the selection of appropriate combinations of markers for population genetic studies. Genetic diversity of these novel markers was assessed in 96 individuals from three populations in China (Harbin, Dali, and Guiyang). The results showed that all these 18 loci were highly polymorphic; the number of alleles ranged from 2 to 15, with an average of 5.50 alleles per locus. The observed (H(O)) and expected (H(E)) heterozygosities ranged from 0.072 to 0.707 and 0.089 to 0.851, respectively. Furthermore, only two locus/population combinations (WFT144 in Dali and WFT50 in Guiyang) significantly deviated from Hardy-Weinberg equilibrium (HWE). Pairwise F(ST) analysis showed a low but significant differentiation (0.026 < F(ST) < 0.032) among all three pairwise population comparisons. Sequence analysis of alleles per locus revealed a complex mutational pattern of these EST-SSRs. Thus, these EST-SSRs are useful markers but greater attention should be paid to the mutational characteristics of these microsatellites when they are used in population genetic studies.

  11. In vitro and in vivo effect of 2,6-Di-tert-butyl-4-methylphenol as an antibiofilm agent against quorum sensing mediated biofilm formation of Vibrio spp.

    PubMed

    Santhakumari, Sivasubramanian; Jayakumar, Rengarajan; Logalakshmi, Ravichandran; Prabhu, Narayanan Marimuthu; Abdul Nazar, Abdul Kuthus; Karutha Pandian, Shunmugiah; Veera Ravi, Arumugam

    2018-05-25

    This study unveils the in vitro and in vivo antibiofilm potential of 2,6-Di-tert-butyl-4-methylphenol (DTBMP) from Chroococcus turgidus against Vibrio spp. In the preliminary study, cell free culture supernatant (CFCS) of C. turgidus inhibited the violacein production in biomarker strain Chromobacterium violaceum and its mutant strain CV026 in a dose dependent manner. The effective biofilm inhibitory concentration (BIC) of pure compound DTBMP from C. turgidus was identified as 250 μg/ml concentration in tested Vibrio species. Furthermore, DTBMP proved to effectively inhibit the bioluminescence production in V. harveyi and other biofilm related virulence traits such as exopolysaccharides (EPS) production, hydrophobicity index, swimming and swarming motility at its BIC concentration in three major pathogenic vibrios: V. harveyi, V. parahaemolyticus and V. vulnificus. The antibiofilm potential of DTBMP was validated through light, confocal laser scanning and scanning electron microscopic analyses. In addition, the non-bactericidal effect of DTBMP was determined through growth curve and 2,3-bis (2-methyloxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) assay. Real-time PCR studies revealed the down-regulation of master quorum sensing (QS) regulator genes of V. harveyi such as luxR, luxS, luxP, luxQ and luxO on treatment with DTBMP. In vivo results confirmed that DTBMP augmented the survival rate of Litopenaeus vannamei larvae up to 75, 88 and 66% upon infection with V. harveyi, V. parahaemolyticus and V. vulnificus, respectively. The results of this study ascertain the promising effects of DTBMP as an antibiofilm agent, which could be positively explored to treat biofilm-associated vibrios infections in aquaculture. Copyright © 2018 Elsevier B.V. All rights reserved.

  12. Enzyme Function Initiative-Enzyme Similarity Tool (EFI-EST): A web tool for generating protein sequence similarity networks.

    PubMed

    Gerlt, John A; Bouvier, Jason T; Davidson, Daniel B; Imker, Heidi J; Sadkhin, Boris; Slater, David R; Whalen, Katie L

    2015-08-01

    The Enzyme Function Initiative, an NIH/NIGMS-supported Large-Scale Collaborative Project (EFI; U54GM093342; http://enzymefunction.org/), is focused on devising and disseminating bioinformatics and computational tools as well as experimental strategies for the prediction and assignment of functions (in vitro activities and in vivo physiological/metabolic roles) to uncharacterized enzymes discovered in genome projects. Protein sequence similarity networks (SSNs) are visually powerful tools for analyzing sequence relationships in protein families (H.J. Atkinson, J.H. Morris, T.E. Ferrin, and P.C. Babbitt, PLoS One 2009, 4, e4345). However, the members of the biological/biomedical community have not had access to the capability to generate SSNs for their "favorite" protein families. In this article we announce the EFI-EST (Enzyme Function Initiative-Enzyme Similarity Tool) web tool (http://efi.igb.illinois.edu/efi-est/) that is available without cost for the automated generation of SSNs by the community. The tool can create SSNs for the "closest neighbors" of a user-supplied protein sequence from the UniProt database (Option A) or of members of any user-supplied Pfam and/or InterPro family (Option B). We provide an introduction to SSNs, a description of EFI-EST, and a demonstration of the use of EFI-EST to explore sequence-function space in the OMP decarboxylase superfamily (PF00215). This article is designed as a tutorial that will allow members of the community to use the EFI-EST web tool for exploring sequence/function space in protein families. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Characterization of a novel deep-sea microbial esterase EstC10 and its use in the generation of ( R)-methyl2-chloropropionate

    NASA Astrophysics Data System (ADS)

    Gong, Yanhui; Ma, Sanmei; Wang, Yongfei; Xu, Yongkai; Sun, Aijun; Zhang, Yun; Hu, Yunfeng

    2018-03-01

    A novel esterase EstC10 from Bacillus sp. CX01 isolated from the deep sea of the Western Pacific Ocean and the functionalities of EstC10 was characterized. At present, the reports about the kinetic resolution of racemic methyl 2-chloropropionate were quite rare. So we developed deep-sea microbial esterase EstC10 as a novel biocatalyst in the kinetic resolution of racemic methyl 2-chloropropionate and generate ( R)-methyl 2-chloropropionate with high enantiomeric excess (>99%) after the optimization of process parameters such as pH, temperature, organic co-solvents, surfactants, substrate concentration and reaction time. Notably, the optimal substrate concentration (80 mmol/L) of esterase EstC10 was higher than the kinetic resolution of another esterase, Est12-7 (50 mmol/L). The novel microbial esterase EstC10 identified from the deep sea was a promising green biocatalyst in the generation of ( R)-methyl 2-chloropropionate as well of many other valuable chiral chemicals in industry.

  14. Transcriptome analysis of the desert locust central nervous system: production and annotation of a Schistocerca gregaria EST database.

    PubMed

    Badisco, Liesbeth; Huybrechts, Jurgen; Simonet, Gert; Verlinden, Heleen; Marchal, Elisabeth; Huybrechts, Roger; Schoofs, Liliane; De Loof, Arnold; Vanden Broeck, Jozef

    2011-03-21

    The desert locust (Schistocerca gregaria) displays a fascinating type of phenotypic plasticity, designated as 'phase polyphenism'. Depending on environmental conditions, one genome can be translated into two highly divergent phenotypes, termed the solitarious and gregarious (swarming) phase. Although many of the underlying molecular events remain elusive, the central nervous system (CNS) is expected to play a crucial role in the phase transition process. Locusts have also proven to be interesting model organisms in a physiological and neurobiological research context. However, molecular studies in locusts are hampered by the fact that genome/transcriptome sequence information available for this branch of insects is still limited. We have generated 34,672 raw expressed sequence tags (EST) from the CNS of desert locusts in both phases. These ESTs were assembled in 12,709 unique transcript sequences and nearly 4,000 sequences were functionally annotated. Moreover, the obtained S. gregaria EST information is highly complementary to the existing orthopteran transcriptomic data. Since many novel transcripts encode neuronal signaling and signal transduction components, this paper includes an overview of these sequences. Furthermore, several transcripts being differentially represented in solitarious and gregarious locusts were retrieved from this EST database. The findings highlight the involvement of the CNS in the phase transition process and indicate that this novel annotated database may also add to the emerging knowledge of concomitant neuronal signaling and neuroplasticity events. In summary, we met the need for novel sequence data from desert locust CNS. To our knowledge, we hereby also present the first insect EST database that is derived from the complete CNS. The obtained S. gregaria EST data constitute an important new source of information that will be instrumental in further unraveling the molecular principles of phase polyphenism, in further establishing

  15. Pilot survey of expressed sequence tags (ESTs) from the asexual blood stages of Plasmodium vivax in human patients.

    PubMed

    Merino, Emilio F; Fernandez-Becerra, Carmen; Madeira, Alda M B N; Machado, Ariane L; Durham, Alan; Gruber, Arthur; Hall, Neil; del Portillo, Hernando A

    2003-07-21

    Plasmodium vivax is the most widely distributed human malaria, responsible for 70-80 million clinical cases each year and large socio-economical burdens for countries such as Brazil where it is the most prevalent species. Unfortunately, due to the impossibility of growing this parasite in continuous in vitro culture, research on P. vivax remains largely neglected. A pilot survey of expressed sequence tags (ESTs) from the asexual blood stages of P. vivax was performed. To do so, 1,184 clones from a cDNA library constructed with parasites obtained from 10 different human patients in the Brazilian Amazon were sequenced. Sequences were automatedly processed to remove contaminants and low quality reads. A total of 806 sequences with an average length of 586 bp met such criteria and their clustering revealed 666 distinct events. The consensus sequence of each cluster and the unique sequences of the singlets were used in similarity searches against different databases that included P. vivax, Plasmodium falciparum, Plasmodium yoelii, Plasmodium knowlesi, Apicomplexa and the GenBank non-redundant database. An E-value of <10(-30) was used to define a significant database match. ESTs were manually assigned a gene ontology (GO) terminology A total of 769 ESTs could be assigned a putative identity based upon sequence similarity to known proteins in GenBank. Moreover, 292 ESTs were annotated and a GO terminology was assigned to 164 of them. These are the first ESTs reported for P. vivax and, as such, they represent a valuable resource to assist in the annotation of the P. vivax genome currently being sequenced. Moreover, since the GC-content of the P. vivax genome is strikingly different from that of P. falciparum, these ESTs will help in the validation of gene predictions for P. vivax and to create a gene index of this malaria parasite.

  16. Characterization and comparison of EST-SSR and TRAP markers for genetic analysis of the Japanese persimmon Diospyros kaki.

    PubMed

    Luo, C; Zhang, F; Zhang, Q L; Guo, D Y; Luo, Z R

    2013-01-09

    We developed and characterized expressed sequence tags (ESTs)-simple sequence repeats (SSRs) and targeted region amplified polymorphism (TRAP) markers to examine genetic relationships in the persimmon genus Diospyros gene pool. In total, we characterized 14 EST-SSR primer pairs and 36 TRAP primer combinations, which were amplified across 20 germplasms of 4 species in the genus Diospyros. We used various genetic parameters, including effective multiplex ratio (EMR), diversity index (DI), and marker index (MI), to test the utility of these markers. TRAP markers gave higher EMR (24.85) but lower DI (0.33), compared to EST-SSRs (EMR = 3.65, DI = 0.34). TRAP gave a very high MI (8.08), which was about 8 times than the MI of EST-SSR (1.25). These markers were utilized for phylogenetic inference of 20 genotypes of Diospyros kaki Thunb. and allied species, with a result that all kaki genotypes clustered closely and 3 allied species formed an independent group. These markers could be further exploited for large-scale genetic relationship inference.

  17. Unravelling the genome of long chain N-acylhomoserine lactone-producing Acinetobacter sp. strain GG2 and identification of its quorum sensing synthase gene

    PubMed Central

    How, Kah Yan; Hong, Kar-Wai; Sam, Choon-Kook; Koh, Chong-Lek; Yin, Wai-Fong; Chan, Kok-Gan

    2015-01-01

    Myriad proteobacteria use N-acyl homoserine lactone (AHL) molecules as quorum sensing (QS) signals to regulate different physiological functions, including virulence, antibiotic production, and biofilm formation. Many of these proteobacteria possess LuxI/LuxR system as the QS mechanism. Recently, we reported the 3.89 Mb genome of Acinetobacter sp. strain GG2. In this work, the genome of this long chain AHL-producing bacterium was unravelled which led to the molecular characterization of luxI homologue, designated as aciI. This 552 bp gene was cloned and overexpressed in Escherichia coli BL21(DE3). The purified protein was ∼20.5 kDa and is highly similar to several autoinducer proteins of LuxI family among Acinetobacter species. To verify the AHL synthesis activity of this protein, high-resolution liquid chromatography–mass spectrometry analysis revealed the production of 3-oxo-dodecanoyl-homoserine lactone and 3-hydroxy-dodecanoyl-homoserine lactone from induced E. coli harboring the recombinant AciI. Our data show for the first time, the cloning and characterization of the luxI homologue from Acinetobacter sp. strain GG2, and confirmation of its AHLs production. These data are of great significance as the annotated genome of strain GG2 has provided a valuable insight in the study of autoinducer molecules and its roles in QS mechanism of the bacterium. PMID:25926817

  18. MuSICa at GRIS: a prototype image slicer for EST at GREGOR

    NASA Astrophysics Data System (ADS)

    Calcines, A.; Collados, M.; López, R. L.

    2013-05-01

    This communication presents a prototype image slicer for the 4-m European Solar Telescope (EST) designed for the spectrograph of the 1.5-m GREGOR solar telescope (GRIS). The design of this integral field unit has been called MuSICa (Multi-Slit Image slicer based on collimator-Camera). It is a telecentric system developed specifically for the integral field, high resolution spectrograph of EST and presents multi-slit capability, reorganizing a bidimensional field of view of 80 arcsec^{2} into 8 slits, each one of them with 200 arcsec length × 0.05 arcsec width. It minimizes the number of optical components needed to fulfil this multi-slit capability, three arrays of mirrors: slicer, collimator and camera mirror arrays (the first one flat and the other two spherical). The symmetry of the layout makes it possible to overlap the pupil images associated to each part of the sliced entrance field of view. A mask with only one circular aperture is placed at the pupil position. This symmetric characteristic offers some advantages: facilitates the manufacturing process, the alignment and reduces the costs. In addition, it is compatible with two modes of operation: spectroscopic and spectro-polarimetric, offering a great versatility. The optical quality of the system is diffraction-limited. The prototype will improve the performances of GRIS at GREGOR and is part of the feasibility study of the integral field unit for the spectrographs of EST. Although MuSICa has been designed as a solar image slicer, its concept can also be applied to night-time astronomical instruments (Collados et al. 2010, Proc. SPIE, Vol. 7733, 77330H; Collados et al. 2012, AN, 333, 901; Calcines et al. 2010, Proc. SPIE, Vol. 7735, 77351X)

  19. From the Field: Interview with Susan R. Easterbrooks and Ellen L. Estes

    ERIC Educational Resources Information Center

    Montgomery, Judy

    2010-01-01

    This article presents an interview with Susan R. Easterbrooks, a professor of deaf education in the Educational Psychology and Special Education Department at Georgia State University in Atlanta, and Ellen L. Estes, the coordinator of the Katherine Hamm Center at the Atlanta Speech School, on their new book "Helping Deaf and Hard of Hearing…

  20. EstA from Arthrobacter nitroguajacolicus Rü61a, a thermo- and solvent-tolerant carboxylesterase related to class C beta-lactamases.

    PubMed

    Schütte, Marcus; Fetzner, Susanne

    2007-03-01

    The estA gene encoding a novel cytoplasmic carboxylesterase from Arthrobacter nitroguajacolicus Rü61a was expressed in Escherichia coli. Sequence analysis and secondary structure predictions suggested that EstA belongs to the family VIII esterases, which are related to class C beta-lactamases. The S-x-x-K motif that in beta-lactamases contains the catalytic nucleophile, and a putative active-site tyrosine residue are conserved in EstA. The native molecular mass of hexahistidine-tagged (His6) EstA, purified by metal chelate affinity chromatography, was estimated to be 95 kDa by gel filtration, whereas the His6EstA peptide has a calculated molecular mass of 42.1 kDa. The enzyme catalyzes the hydrolysis of short-chain phenylacyl esters and triglycerides, and shows weak activity toward 2-hydroxy- and 2-nitroacetanilide. Its catalytic activity was inhibited by the serine-specific effector phenylmethylsulfonyl fluoride, and by Cd2+ and Hg2+ ions. Maximum activity of His6EstA was observed at a pH of 9.5 and a temperature of 50 degrees C to 60 degrees C. The enzyme was fairly thermostable. After 19 days at 50 degrees C and after 24 hours at 60 degrees C, its residual relative esterase activity toward phenylacetate was still 53% and 30%, respectively. Exposure of His6EstA to buffer-solvent mixtures showed that the enzyme was inactivated by several high log P (hydrophobic) solvents, whereas it showed remarkable stability and activity in up to 30% (by volume) of polar (low log P) organic solvents such as dimethylsulfoxide, methanol, acetonitrile, acetone, and propanol.

  1. Influence of periodic vs continuous daily bright light exposure on development of experimental myopia in the chick.

    PubMed

    Backhouse, Simon; Collins, Andrew V; Phillips, John R

    2013-09-01

    In children, time spent outdoors has a protective effect against myopia development. In animal models, bright light reduces the development of experimental myopia. This study investigates how an increase in daily light exposure, presented either continuously during the day or periodically at different times of day, influences the development of experimental myopia in the chick. Myopia was induced in Cobb Chicks (Gallus domesticus) by monocular deprivation (MD) of form vision with a translucent diffuser for 3 days (from 4 days of age) under a 12:12 light: dark cycle. MD control chicks were exposed to constant 300 lux (n = 11) during the light period. MD treatment groups received either constant 2000 lux (n = 11) during the light period or 300 lux for 10 h with a 2 h period of bright light (10 000 lux), either in the morning (n = 10), midday (n = 10) or evening (n = 10), giving the same total daily light exposure as the 2000 lux group. After 3 days of MD, refractive status, corneal curvature and axial eye dimensions were measured for all eyes under anaesthesia. Myopia in the constant 2000 lux group (-4.94 ± 1.21 D) was significantly less than in the 300 lux control group (-9.73 ± 0.96 D; p = 0.022). However, compared to the 300 lux control group, 2 h periods of 10 000 lux did not produce significant effects on refraction when presented either in the morning (-9.98 ± 0.85; p = 1.00), midday (-8.00 ± 1.26; p = 0.80), or evening (-13.14 ± 1.16 D; p = 0.20), although significantly less myopia was induced in the midday group compared to the evening group (p = 0.018). Orthogonal regression showed that myopia development was matched by changes in vitreous chamber depth (R(2)  = 0.69; p < 0.0001). In chicks, an increase in daily light exposure continuously during the day is more effective at inhibiting myopia than adding an equivalent dose within a 2 h period of bright light. A weak time-of-day effect also appears

  2. Rational design of a carboxylic esterase RhEst1 based on computational analysis of substrate binding

    DOE PAGES

    Chen, Qi; Luan, Zheng -Jiao; Yu, Hui -Lei; ...

    2015-10-31

    A new carboxylic esterase RhEst1 which catalyzes the hydrolysis of (S)-(+)-2,2-dimethylcyclopropanecarboxylate (S-DmCpCe), the key chiral building block of cilastatin, was identified and subsequently crystallized in our previous work. Mutant RhEst 1A147I/V148F/G254A was found to show a 5-fold increase in the catalytic activity. In this work, molecular dynamic simulations were performed to elucidate the molecular determinant of the enzyme activity. Our simulations show that the substrate binds much more strongly in the A147I/V148F/G254A mutant than in wild type, with more hydrogen bonds formed between the substrate and the catalytic triad and the oxyanion hole. The OH group of the catalytic residuemore » Ser101 in the mutant is better positioned to initiate the nucleophilic attack on S-DmCpCe. Interestingly, the "170-179" loop which is involved in shaping the catalytic sites and facilitating the product release shows remarkable dynamic differences in the two systems. Based on the simulation results, six residues were identified as potential "hot-spots" for further experimental testing. Consequently, the G126S and R133L mutants show higher catalytic efficiency as compared with the wild type. In conclusion, this work provides molecular-level insights into the substrate binding mechanism of carboxylic esterase RhEst1, facilitating future experimental efforts toward developing more efficient RhEst1 variants for industrial applications.« less

  3. Characteristics of the Lotus japonicus gene repertoire deduced from large-scale expressed sequence tag (EST) analysis.

    PubMed

    Asamizu, Erika; Nakamura, Yasukazu; Sato, Shusei; Tabata, Satoshi

    2004-02-01

    To perform a comprehensive analysis of genes expressed in a model legume, Lotus japonicus, a total of 74472 3'-end expressed sequence tags (EST) were generated from cDNA libraries produced from six different organs. Clustering of sequences was performed with an identity criterion of 95% for 50 bases, and a total of 20457 non-redundant sequences, 8503 contigs and 11954 singletons were generated. EST sequence coverage was analyzed by using the annotated L. japonicus genomic sequence and 1093 of the 1889 predicted protein-encoding genes (57.9%) were hit by the EST sequence(s). Gene content was compared to several plant species. Among the 8503 contigs, 471 were identified as sequences conserved only in leguminous species and these included several disease resistance-related genes. This suggested that in legumes, these genes may have evolved specifically to resist pathogen attack. The rate of gene sequence divergence was assessed by comparing similarity level and functional category based on the Gene Ontology (GO) annotation of Arabidopsis genes. This revealed that genes encoding ribosomal proteins, as well as those related to translation, photosynthesis, and cellular structure were more abundantly represented in the highly conserved class, and that genes encoding transcription factors and receptor protein kinases were abundantly represented in the less conserved class. To make the sequence information and the cDNA clones available to the research community, a Web database with useful services was created at http://www.kazusa.or.jp/en/plant/lotus/EST/.

  4. DNA-microarrays identification of Streptococcus mutans genes associated with biofilm thickness

    PubMed Central

    Shemesh, Moshe; Tam, Avshalom; Kott-Gutkowski, Miriam; Feldman, Mark; Steinberg, Doron

    2008-01-01

    Background A biofilm is a complex community of microorganisms that develop on surfaces in diverse environments. The thickness of the biofilm plays a crucial role in the physiology of the immobilized bacteria. The most cariogenic bacteria, mutans streptococci, are common inhabitants of a dental biofilm community. In this study, DNA-microarray analysis was used to identify differentially expressed genes associated with the thickness of S. mutans biofilms. Results Comparative transcriptome analyses indicated that expression of 29 genes was differentially altered in 400- vs. 100-microns depth and 39 genes in 200- vs. 100-microns biofilms. Only 10 S. mutans genes showed differential expression in both 400- vs. 100-microns and 200- vs. 100-microns biofilms. All of these genes were upregulated. As sucrose is a predominant factor in oral biofilm development, its influence was evaluated on selected genes expression in the various depths of biofilms. The presence of sucrose did not noticeably change the regulation of these genes in 400- vs. 100-microns and/or 200- vs. 100-microns biofilms tested by real-time RT-PCR. Furthermore, we analyzed the expression profile of selected biofilm thickness associated genes in the luxS- mutant strain. The expression of those genes was not radically changed in the mutant strain compared to wild-type bacteria in planktonic condition. Only slight downregulation was recorded in SMU.2146c, SMU.574, SMU.609, and SMU.987 genes expression in luxS- bacteria in biofilm vs. planktonic environments. Conclusion These findings reveal genes associated with the thickness of biofilms of S. mutans. Expression of these genes is apparently not regulated directly by luxS and is not necessarily influenced by the presence of sucrose in the growth media. PMID:19114020

  5. Bioluminescent bioreporter integrated circuit devices and methods for detecting estrogen

    DOEpatents

    Simpson, Michael L.; Paulus, Michael J.; Sayler, Gary S.; Applegate, Bruce M.; Ripp, Steven A.

    2006-08-15

    Bioelectronic devices for the detection of estrogen include a collection of eukaryotic cells which harbor a recombinant lux gene from a high temperature microorganism wherein the gene is operably linked with a heterologous promoter gene. A detectable light-emitting lux gene product is expressed in the presence of the estrogen and detected by the device.

  6. Expression, Purification, and Characterization of a Recombinant Flavin Reductase from the Luminescent Marine Bacterium "Photobacterium Leiognathi": A Set of Exercises for Students

    ERIC Educational Resources Information Center

    Crowley, Thomas E.

    2010-01-01

    In "Photobacterium," the flavin reductase encoded by "lux"G regenerates the reduced form of flavin mononucleotide (FMN). Reduced FMN is one of the substrates of the luciferase enzyme that catalyzes a light-emitting reaction. A set of experiments, that employs a "lux"G-expression plasmid construct (pGhis) and is suitable for an undergraduate…

  7. Exploiting rice-sorghum synteny for targeted development of EST-SSRs to enrich the sorghum genetic linkage map.

    PubMed

    Ramu, P; Kassahun, B; Senthilvel, S; Ashok Kumar, C; Jayashree, B; Folkertsma, R T; Reddy, L Ananda; Kuruvinashetti, M S; Haussmann, B I G; Hash, C T

    2009-11-01

    The sequencing and detailed comparative functional analysis of genomes of a number of select botanical models open new doors into comparative genomics among the angiosperms, with potential benefits for improvement of many orphan crops that feed large populations. In this study, a set of simple sequence repeat (SSR) markers was developed by mining the expressed sequence tag (EST) database of sorghum. Among the SSR-containing sequences, only those sharing considerable homology with rice genomic sequences across the lengths of the 12 rice chromosomes were selected. Thus, 600 SSR-containing sorghum EST sequences (50 homologous sequences on each of the 12 rice chromosomes) were selected, with the intention of providing coverage for corresponding homologous regions of the sorghum genome. Primer pairs were designed and polymorphism detection ability was assessed using parental pairs of two existing sorghum mapping populations. About 28% of these new markers detected polymorphism in this 4-entry panel. A subset of 55 polymorphic EST-derived SSR markers were mapped onto the existing skeleton map of a recombinant inbred population derived from cross N13 x E 36-1, which is segregating for Striga resistance and the stay-green component of terminal drought tolerance. These new EST-derived SSR markers mapped across all 10 sorghum linkage groups, mostly to regions expected based on prior knowledge of rice-sorghum synteny. The ESTs from which these markers were derived were then mapped in silico onto the aligned sorghum genome sequence, and 88% of the best hits corresponded to linkage-based positions. This study demonstrates the utility of comparative genomic information in targeted development of markers to fill gaps in linkage maps of related crop species for which sufficient genomic tools are not available.

  8. The EVER-EST Virtual Research Environment for the European Volcano Supersites

    NASA Astrophysics Data System (ADS)

    Salvi, S.; Trasatti, E.; Rubbia, G.; Romaniello, V.; Marelli, F.

    2017-12-01

    EVER-EST (European Virtual Environment for Research - Earth Science Themes) is an European H2020 project (2015-2018) aimed at the creation of a Virtual Research Environment (VRE) for the Earth Sciences. The VRE is intended to enhance the ability to collaborate and share knowledge and experience among scientists. One of the innovations of the project is the exploitation of the "Research Object" concept (http://www.rohub.org). Research Objects encapsulate not only data and publications, but also algorithms, codes, results, and workflows that can be stored, shared and re-used. Four scientific communities are involved in the EVER-EST project: land monitoring, natural hazards, marine biology, and the GEO Geohazard Supersites community (http://www.earthobservations.org/gsnl.php). The latter is represented in the project by INGV and the University of Iceland, and has provided user requirements to tailor the VRE to the common needs of the worldwide Supersite communities. To develop and test the VRE we have defined user scenarios and created Research Objects embedding research activities and workflows on the Permanent Supersites Campi Flegrei, Mount Etna and Icelandic Volcanoes (http://vm1.everest.psnc.pl/supersites/). While these Supersites are test sites for the platform, during the last year of the project other Supersites may also be involved to demonstrate the added value of the collaborative environment in research activities aiming to support Disaster Risk Reduction. Using the VRE, scientists are able to collaborate with colleagues located in different parts of the world, in a simple and effective way. This includes being able to remotely access and share data, research results and ideas, to carry out training sessions and discussions, to compare different results and models, and to synthesize many different pieces of information in a single consensus product to be disseminated to end-users. In particular, a further need of the Supersite scientists, which can be

  9. High polymorphism in Est-SSR loci for cellulose synthase and β-amylase of sugarcane varieties (Saccharum spp.) used by the industrial sector for ethanol production.

    PubMed

    Augusto, Raphael; Maranho, Rone Charles; Mangolin, Claudete Aparecida; Pires da Silva Machado, Maria de Fátima

    2015-01-01

    High and low polymorphisms in simple sequence repeats of expressed sequence tag (EST-SSR) for specific proteins and enzymes, such as β-amylase, cellulose synthase, xyloglucan endotransglucosylase, fructose 1,6-bisphosphate aldolase, and fructose 1,6-bisphosphatase, were used to illustrate the genetic divergence within and between varieties of sugarcane (Saccharum spp.) and to guide the technological paths to optimize ethanol production from lignocellulose biomass. The varieties RB72454, RB867515, RB92579, and SP813250 on the second stage of cutting, all grown in the state of Paraná (PR), and the varieties RB92579 and SP813250 cultured in the PR state and in Northeastern Brazil, state of Pernambuco (PE), were analyzed using five EST-SSR primers for EstC66, EstC67, EstC68, EstC69, and EstC91 loci. Genetic divergence was evident in the EstC67 and EstC69 loci for β-amylase and cellulose synthase, respectively, among the four sugarcane varieties. An extremely high level of genetic differentiation was also detected in the EstC67 locus from the RB82579 and SP813250 varieties cultured in the PR and PE states. High polymorphism in SSR of the cellulose synthase locus may explain the high variability of substrates used in pretreatment and enzymatic hydrolysis processes, which has been an obstacle to effective industrial adaptations.

  10. Determination of the genetic diversity of vegetable soybean [Glycine max (L.) Merr.] using EST-SSR markers*

    PubMed Central

    Zhang, Gu-wen; Xu, Sheng-chun; Mao, Wei-hua; Hu, Qi-zan; Gong, Ya-ming

    2013-01-01

    The development of expressed sequence tag-derived simple sequence repeats (EST-SSRs) provided a useful tool for investigating plant genetic diversity. In the present study, 22 polymorphic EST-SSRs from grain soybean were identified and used to assess the genetic diversity in 48 vegetable soybean accessions. Among the 22 EST-SSR loci, tri-nucleotides were the most abundant repeats, accounting for 50.00% of the total motifs. GAA was the most common motif among tri-nucleotide repeats, with a frequency of 18.18%. Polymorphic analysis identified a total of 71 alleles, with an average of 3.23 per locus. The polymorphism information content (PIC) values ranged from 0.144 to 0.630, with a mean of 0.386. Observed heterozygosity (H o) values varied from 0.0196 to 1.0000, with an average of 0.6092, while the expected heterozygosity (H e) values ranged from 0.1502 to 0.6840, with a mean value of 0.4616. Principal coordinate analysis and phylogenetic tree analysis indicated that the accessions could be assigned to different groups based to a large extent on their geographic distribution, and most accessions from China were clustered into the same groups. These results suggest that Chinese vegetable soybean accessions have a narrow genetic base. The results of this study indicate that EST-SSRs from grain soybean have high transferability to vegetable soybean, and that these new markers would be helpful in taxonomy, molecular breeding, and comparative mapping studies of vegetable soybean in the future. PMID:23549845

  11. Rational design of a carboxylic esterase RhEst1 based on computational analysis of substrate binding.

    PubMed

    Chen, Qi; Luan, Zheng-Jiao; Yu, Hui-Lei; Cheng, Xiaolin; Xu, Jian-He

    2015-11-01

    A new carboxylic esterase RhEst1 which catalyzes the hydrolysis of (S)-(+)-2,2-dimethylcyclopropanecarboxylate (S-DmCpCe), the key chiral building block of cilastatin, was identified and subsequently crystallized in our previous work. Mutant RhEst1A147I/V148F/G254A was found to show a 5-fold increase in the catalytic activity. In this work, molecular dynamic simulations were performed to elucidate the molecular determinant of the enzyme activity. Our simulations show that the substrate binds much more strongly in the A147I/V148F/G254A mutant than in wild type, with more hydrogen bonds formed between the substrate and the catalytic triad and the oxyanion hole. The OH group of the catalytic residue Ser101 in the mutant is better positioned to initiate the nucleophilic attack on S-DmCpCe. Interestingly, the "170-179" loop which is involved in shaping the catalytic sites and facilitating the product release shows remarkable dynamic differences in the two systems. Based on the simulation results, six residues were identified as potential "hot-spots" for further experimental testing. Consequently, the G126S and R133L mutants show higher catalytic efficiency as compared with the wild type. This work provides molecular-level insights into the substrate binding mechanism of carboxylic esterase RhEst1, facilitating future experimental efforts toward developing more efficient RhEst1 variants for industrial applications. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Autoinducer-2 Production in Campylobacter jejuni Contributes to Chicken Colonization ▿

    PubMed Central

    Quiñones, Beatriz; Miller, William G.; Bates, Anna H.; Mandrell, Robert E.

    2009-01-01

    Inactivation of luxS, encoding an AI-2 biosynthesis enzyme, in Campylobacter jejuni strain 81-176 significantly reduced colonization of the chick lower gastrointestinal tract, chemotaxis toward organic acids, and in vitro adherence to LMH chicken hepatoma cells. Thus, AI-2 production in C. jejuni contributes to host colonization and interactions with epithelial cells. PMID:19011073

  13. Absolute NMR shielding scales and nuclear spin–rotation constants in {sup 175}LuX and {sup 197}AuX (X = {sup 19}F, {sup 35}Cl, {sup 79}Br and {sup 127}I)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Demissie, Taye B., E-mail: taye.b.demissie@uit.no; Komorovsky, Stanislav; Repisky, Michal

    2015-10-28

    We present nuclear spin–rotation constants, absolute nuclear magnetic resonance (NMR) shielding constants, and shielding spans of all the nuclei in {sup 175}LuX and {sup 197}AuX (X = {sup 19}F, {sup 35}Cl, {sup 79}Br, {sup 127}I), calculated using coupled-cluster singles-and-doubles with a perturbative triples (CCSD(T)) correction theory, four-component relativistic density functional theory (relativistic DFT), and non-relativistic DFT. The total nuclear spin–rotation constants determined by adding the relativistic corrections obtained from DFT calculations to the CCSD(T) values are in general in agreement with available experimental data, indicating that the computational approach followed in this study allows us to predict reliable results formore » the unknown spin–rotation constants in these molecules. The total NMR absolute shielding constants are determined for all the nuclei following the same approach as that applied for the nuclear spin–rotation constants. In most of the molecules, relativistic effects significantly change the computed shielding constants, demonstrating that straightforward application of the non-relativistic formula relating the electronic contribution to the nuclear spin–rotation constants and the paramagnetic contribution to the shielding constants does not yield correct results. We also analyze the origin of the unusually large absolute shielding constant and its relativistic correction of gold in AuF compared to the other gold monohalides.« less

  14. Development and Characterization of 1,906 EST-SSR Markers from Unigenes in Jute (Corchorus spp.)

    PubMed Central

    Zhang, Liwu; Li, Yanru; Tao, Aifen; Fang, Pingping; Qi, Jianmin

    2015-01-01

    Jute, comprising white and dark jute, is the second important natural fiber crop after cotton worldwide. However, the lack of expressed sequence tag-derived simple sequence repeat (EST-SSR) markers has resulted in a large gap in the improvement of jute. Previously, de novo 48,914 unigenes from white jute were assembled. In this study, 1,906 EST-SSRs were identified from these assembled uingenes. Among these markers, di-, tri- and tetra-nucleotide repeat types were the abundant types (12.0%, 56.9% and 21.6% respectively). The AG-rich or GA-rich nucleotide repeats were the predominant. Subsequently, a sample of 116 SSRs, located in genes encoding transcription factors and cellulose synthases, were selected to survey polymorphisms among12 diverse jute accessions. Of these, 83.6% successfully amplified at least one fragment and detected polymorphism among the 12diverse genotypes, indicating that the newly developed SSRs are of good quality. Furthermore, the genetic similarity coefficients of all the 12 accessions were evaluated using 97 polymorphic SSRs. The cluster analysis divided the jute accessions into two main groups with genetic similarity coefficient of 0.61. These EST-SSR markers not only enrich molecular markers of jute genome, but also facilitate genetic and genomic researches in jute. PMID:26512891

  15. Bioinformatic mining of EST-SSR loci in the Pacific oyster, Crassostrea gigas.

    PubMed

    Wang, Y; Ren, R; Yu, Z

    2008-06-01

    A set of expressed sequence tag-simple sequence repeat (EST-SSR) markers of the Pacific oyster, Crassostrea gigas, was developed through bioinformatic mining of the GenBank public database. As of June 30, 2007, a total of 5132 EST sequences from GenBank were downloaded and screened for di-, tri- and tetra-nucleotide repeats, with criteria set at a minimum of 5, 4 and 4 repeats for the three categories of SSRs respectively. Seventeen polymorphic microsatellite markers were characterized. Allele numbers ranged from 3 to 10, and the observed and expected heterozygosity values varied from 0.125 to 0.770 and from 0.113 to 0.732 respectively. Eleven loci were at Hardy-Weinberg equilibrium (HWE); the other six loci showed significant departure from HWE (P < 0.01), suggesting possible presence of null alleles. Pairwise check of linkage disequilibrium (LD) indicated that 11 of 136 pairs of loci showed significant LD (P < 0.01), likely due to HWE present in single markers. Cross-species amplification was examined for five other Crassostrea species and reasonable results were obtained, promising usefulness of these markers in oyster genetics.

  16. Development of bacteriophage-based bioluminescent bioreporters for monitoring of microbial pathogens

    NASA Astrophysics Data System (ADS)

    Ozen, Aysu; Montgomery, Kacey; Jegier, Pat; Patterson, Stacey; Daumer, Kathleen A.; Ripp, Steven A.; Garland, Jay L.; Sayler, Gary S.

    2004-03-01

    Microorganisms pose numerous problems when present in human occupied enclosed environments. Primary among these are health related hazards, manifested as infectious diseases related to contaminated drinking water, food, or air circulation systems or non-infectious allergy related complications associated with microbial metabolites (sick building syndrome). As a means towards rapid detection of microbial pathogens, we are attempting to harness the specificity of bacterial phage for their host with a modified quorum sensing amplification signal to produce quantifiable bioluminescent (lux) detection on a silicon microluminometer. The bacteriophage itself is metabolically inactive, only achieving replicative capabilities upon infection of its specific host bacterium. Bacteriophage bioluminescent bioreporters contain a genomically inserted luxI component. During an infection event, the phage genes and accompanying luxI construct are taken up by the host bacterium and transcribed, resulting in luxI expression and subsequent activation of a homoserine lactone inducible bioluminescent bioreporter. We constructed a vector carrying the luxI gene under the control of a strong E. coli promoter and cloned it into E. coli. We have shown that it can induce luminescence up to 14,000 counts per second when combined with the bioreporter strain. In their final embodiment, these sensors will be fully independent microelectronic monitors for microbial contamination, requiring only exposure of the biochip to the sample, with on-chip signal processing downloaded directly to the local area network of the environmental control system.

  17. RbsB (NTHI_0632) mediates quorum signal uptake in nontypeable Haemophilus influenzae strain 86-028NP

    PubMed Central

    Armbruster, Chelsie E.; Pang, Bing; Murrah, Kyle; Juneau, Richard A.; Perez, Antonia C.; Weimer, Kristin E.D.; Swords, W. Edward

    2011-01-01

    Summary Nontypeable Haemophilus influenzae (NTHI) is a respiratory commensal and opportunistic pathogen, which persists within biofilms on airway mucosal surfaces. For many species, biofilm formation is impacted by quorum signaling. Our prior work shows that production of autoinducer-2 (AI-2) promotes biofilm development and persistence for NTHI 86-028NP. NTHI 86-028NP encodes an ABC transporter annotated as a ribose transport system that includes a protein (RbsB) with similarity to the Escherichia coli LsrB and Aggregatibacter actinomycetemcomitans RbsB proteins that bind AI-2. In this study, inactivation of rbsB significantly reduced uptake of AI-2 and the AI-2 precursor dihydroxypentanedione (DPD) by NTHI 86-028NP. Moreover, DPD uptake was not competitively inhibited by ribose or other pentose sugars. Transcript levels of rbsB increased in response to DPD and as bacteria approached stationary-phase growth. The NTHI 86-028NP rbsB mutant also formed biofilms with significantly reduced thickness and total biomass and reduced surface phosphorylcholine, similar to a luxS mutant. Infection studies revealed that loss of rbsB impaired bacterial persistence in the chinchilla middle-ear, similar to our previous results with luxS mutants. Based on these data, we conclude that in NTHI 86-028NP, RbsB is a LuxS/AI-2 regulated protein that is required for uptake of and response to AI-2. PMID:21923771

  18. RbsB (NTHI_0632) mediates quorum signal uptake in nontypeable Haemophilus influenzae strain 86-028NP.

    PubMed

    Armbruster, Chelsie E; Pang, Bing; Murrah, Kyle; Juneau, Richard A; Perez, Antonia C; Weimer, Kristin E D; Swords, W Edward

    2011-11-01

    Nontypeable Haemophilus influenzae (NTHI) is a respiratory commensal and opportunistic pathogen, which persists within biofilms on airway mucosal surfaces. For many species, biofilm formation is impacted by quorum signalling. Our prior work shows that production of autoinducer-2 (AI-2) promotes biofilm development and persistence for NTHI 86-028NP. NTHI 86-028NP encodes an ABC transporter annotated as a ribose transport system that includes a protein (RbsB) with similarity to the Escherichia coli LsrB and Aggregatibacter actinomycetemcomitans RbsB proteins that bind AI-2. In this study, inactivation of rbsB significantly reduced uptake of AI-2 and the AI-2 precursor dihydroxypentanedione (DPD) by NTHI 86-028NP. Moreover, DPD uptake was not competitively inhibited by ribose or other pentose sugars. Transcript levels of rbsB increased in response to DPD and as bacteria approached stationary-phase growth. The NTHI 86-028NP rbsB mutant also formed biofilms with significantly reduced thickness and total biomass and reduced surface phosphorylcholine, similar to a luxS mutant. Infection studies revealed that loss of rbsB impaired bacterial persistence in the chinchilla middle ear, similar to our previous results with luxS mutants. Based on these data, we conclude that in NTHI 86-028NP, RbsB is a LuxS/AI-2 regulated protein that is required for uptake of and response to AI-2. © 2011 Blackwell Publishing Ltd.

  19. A distinctive dual-channel quorum-sensing system operates in Vibrio anguillarum.

    PubMed

    Croxatto, Antony; Pride, John; Hardman, Andrea; Williams, Paul; Cámara, Miguel; Milton, Debra L

    2004-06-01

    Many bacterial cells communicate using diffusible signal molecules to monitor cell population density via a process termed quorum sensing. In marine Vibrio species, the Vibrio harveyi-type LuxR protein is a key player in a quorum-sensing phosphorelay cascade, which controls the expression of virulence, symbiotic and survival genes. Previously, we characterized Vibrio anguillarum homologues of LuxR (VanT) and LuxMN (VanMN) and, in this study, we have identified homologues of LuxPQ (VanPQ) and LuxOU (VanOU). In contrast to other Vibrio species, vanT was expressed at low cell density and showed no significant induction as the cell number increased. In addition, although the loss of VanO increased vanT expression, the loss of VanU, unexpectedly, decreased it. Both VanN and VanQ were required for repression of vanT even in a vanU mutant, suggesting an alternative route for VanNQ signal transduction other than via VanU. VanT negatively regulated its own expression by binding and repressing the vanT promoter and by binding and activating the vanOU promoter. The signal relay results in a cellular response as expression of the metalloprotease, empA, was altered similar to that of vanT in all the mutants. Consequently, the V. anguillarum quorum-sensing phosphorelay systems work differently from those of V. harveyi and may be used to limit rather than induce vanT expression.

  20. In-silico and in-vivo analyses of EST databases unveil conserved miRNAs from Carthamus tinctorius and Cynara cardunculus

    PubMed Central

    2012-01-01

    Background MicroRNAs (miRNAs) are small RNAs (21-24 bp) providing an RNA-based system of gene regulation highly conserved in plants and animals. In plants, miRNAs control mRNA degradation or restrain translation, affecting development and responses to stresses. Plant miRNAs show imperfect but extensive complementarity to mRNA targets, making their computational prediction possible, useful when data mining is applied on different species. In this study we used a comparative approach to identify both miRNAs and their targets, in artichoke and safflower. Results Two complete expressed sequence tags (ESTs) datasets from artichoke (3.6·104 entries) and safflower (4.2·104), were analysed with a bioinformatic pipeline and in vitro experiments, identifying 17 potential miRNAs. For each EST, using RNAhybrid program and 953 non redundant miRNA mature sequences, available in mirBase as reference, we searched matching putative targets. 8730 out of 42011 ESTs from safflower and 7145 of 36323 ESTs from artichoke showed at least one predicted miRNA target. BLAST analysis showed that 75% of all ESTs shared at least a common homologous region (E-value < 10-4) and about 50% of these displayed 400 bp or longer aligned sequences as conserved homologous/orthologous (COS) regions. 960 and 890 ESTs of safflower and artichoke organized in COS shared 79 different miRNA targets, considered functionally conserved, and statistically significant when compared with random sequences (signal to noise ratio > 2 and specificity ≥ 0.85). Four highly significant miRNAs selected from in silico data were experimentally validated in globe artichoke leaves. Conclusions Mature miRNAs and targets were predicted within EST sequences of safflower and artichoke. Most of the miRNA targets appeared highly/moderately conserved, highlighting an important and conserved function. In this study we introduce a stringent parameter for the comparative sequence analysis, represented by the identification of the same

  1. JUICE: a data management system that facilitates the analysis of large volumes of information in an EST project workflow.

    PubMed

    Latorre, Mariano; Silva, Herman; Saba, Juan; Guziolowski, Carito; Vizoso, Paula; Martinez, Veronica; Maldonado, Jonathan; Morales, Andrea; Caroca, Rodrigo; Cambiazo, Veronica; Campos-Vargas, Reinaldo; Gonzalez, Mauricio; Orellana, Ariel; Retamales, Julio; Meisel, Lee A

    2006-11-23

    Expressed sequence tag (EST) analyses provide a rapid and economical means to identify candidate genes that may be involved in a particular biological process. These ESTs are useful in many Functional Genomics studies. However, the large quantity and complexity of the data generated during an EST sequencing project can make the analysis of this information a daunting task. In an attempt to make this task friendlier, we have developed JUICE, an open source data management system (Apache + PHP + MySQL on Linux), which enables the user to easily upload, organize, visualize and search the different types of data generated in an EST project pipeline. In contrast to other systems, the JUICE data management system allows a branched pipeline to be established, modified and expanded, during the course of an EST project. The web interfaces and tools in JUICE enable the users to visualize the information in a graphical, user-friendly manner. The user may browse or search for sequences and/or sequence information within all the branches of the pipeline. The user can search using terms associated with the sequence name, annotation or other characteristics stored in JUICE and associated with sequences or sequence groups. Groups of sequences can be created by the user, stored in a clipboard and/or downloaded for further analyses. Different user profiles restrict the access of each user depending upon their role in the project. The user may have access exclusively to visualize sequence information, access to annotate sequences and sequence information, or administrative access. JUICE is an open source data management system that has been developed to aid users in organizing and analyzing the large amount of data generated in an EST Project workflow. JUICE has been used in one of the first functional genomics projects in Chile, entitled "Functional Genomics in nectarines: Platform to potentiate the competitiveness of Chile in fruit exportation". However, due to its ability to

  2. JUICE: a data management system that facilitates the analysis of large volumes of information in an EST project workflow

    PubMed Central

    Latorre, Mariano; Silva, Herman; Saba, Juan; Guziolowski, Carito; Vizoso, Paula; Martinez, Veronica; Maldonado, Jonathan; Morales, Andrea; Caroca, Rodrigo; Cambiazo, Veronica; Campos-Vargas, Reinaldo; Gonzalez, Mauricio; Orellana, Ariel; Retamales, Julio; Meisel, Lee A

    2006-01-01

    Background Expressed sequence tag (EST) analyses provide a rapid and economical means to identify candidate genes that may be involved in a particular biological process. These ESTs are useful in many Functional Genomics studies. However, the large quantity and complexity of the data generated during an EST sequencing project can make the analysis of this information a daunting task. Results In an attempt to make this task friendlier, we have developed JUICE, an open source data management system (Apache + PHP + MySQL on Linux), which enables the user to easily upload, organize, visualize and search the different types of data generated in an EST project pipeline. In contrast to other systems, the JUICE data management system allows a branched pipeline to be established, modified and expanded, during the course of an EST project. The web interfaces and tools in JUICE enable the users to visualize the information in a graphical, user-friendly manner. The user may browse or search for sequences and/or sequence information within all the branches of the pipeline. The user can search using terms associated with the sequence name, annotation or other characteristics stored in JUICE and associated with sequences or sequence groups. Groups of sequences can be created by the user, stored in a clipboard and/or downloaded for further analyses. Different user profiles restrict the access of each user depending upon their role in the project. The user may have access exclusively to visualize sequence information, access to annotate sequences and sequence information, or administrative access. Conclusion JUICE is an open source data management system that has been developed to aid users in organizing and analyzing the large amount of data generated in an EST Project workflow. JUICE has been used in one of the first functional genomics projects in Chile, entitled "Functional Genomics in nectarines: Platform to potentiate the competitiveness of Chile in fruit exportation

  3. Estándar para la Protección del Trabajador Agrícola Revisado

    EPA Pesticide Factsheets

    Estas revisiones al Estándar de Protección a los Trabajadores Agrícolas, promulgado en 1992, proporcionarán protecciones de salud a los trabajadores agrícolas similares a las que ya disponen trabajadores en otras industrias.

  4. Regulation of the yjjQ-bglJ Operon, Encoding LuxR-Type Transcription Factors, and the Divergent yjjP Gene by H-NS and LeuO▿ †

    PubMed Central

    Stratmann, Thomas; Madhusudan, S.; Schnetz, Karin

    2008-01-01

    The yjjQ and bglJ genes encode LuxR-type transcription factors conserved in several enterobacterial species. YjjQ is a potential virulence factor in avian pathogenic Escherichia coli. BglJ counteracts the silencing of the bgl (β-glucoside) operon by H-NS in E. coli K-12. Here we show that yjjQ and bglJ form an operon carried by E. coli K-12, whose expression is repressed by the histone-like nucleoid structuring (H-NS) protein. The LysR-type transcription factor LeuO counteracts this repression. Furthermore, the yjjP gene, encoding a membrane protein of unknown function and located upstream in divergent orientation to the yjjQ-bglJ operon, is likewise repressed by H-NS. Mapping of the promoters as well as the H-NS and LeuO binding sites within the 555-bp intergenic region revealed that H-NS binds to the center of the AT-rich regulatory region and distal to the divergent promoters. LeuO sites map to the center and to positions distal to the yjjQ promoters, while one LeuO binding site overlaps with the divergent yjjP promoter. This latter LeuO site is required for full derepression of the yjjQ promoters. The arrangement of regulatory sites suggests that LeuO restructures the nucleoprotein complex formed by H-NS. Furthermore, the data support the conclusion that LeuO, whose expression is likewise repressed by H-NS and which is a virulence factor in Salmonella enterica, is a master regulator that among other loci, also controls the yjjQ-bglJ operon and thus indirectly the presumptive targets of YjjQ and BglJ. PMID:18055596

  5. EST sequencing and gene expression profiling of defence-related genes from Persea americana infected with Phytophthora cinnamomi

    PubMed Central

    2011-01-01

    Background Avocado (Persea americana) belongs to the Lauraceae family and is an important commercial fruit crop in over 50 countries. The most serious pathogen affecting avocado production is Phytophthora cinnamomi which causes Phytophthora root rot (PRR). Root pathogens such as P. cinnamomi and their interactions with hosts are poorly understood and despite the importance of both the avocado crop and the effect Phytophthora has on its cultivation, there is a lack of molecular knowledge underpinning our understanding of defence strategies against the pathogen. In order to initiate a better understanding of host-specific defence we have generated EST data using 454 pyrosequencing and profiled nine defence-related genes from Pc-infected avocado roots. Results 2.0 Mb of data was generated consisting of ~10,000 reads on a single lane of the GS FLX platform. Using the Newbler assembler 371 contigs were assembled, of which 367 are novel for Persea americana. Genes were classified according to Gene Ontology terms. In addition to identifying root-specific ESTs we were also able to identify and quantify the expression of nine defence-related genes that were differentially regulated in response to P. cinnamomi. Genes such as metallothionein, thaumatin and the pathogenesis related PsemI, mlo and profilin were found to be differentially regulated. Conclusions This is the first study in elucidating the avocado root transcriptome as well as identifying defence responses of avocado roots to the root pathogen P. cinnamomi. Our data is currently the only EST data that has been generated for avocado rootstocks, and the ESTs identified in this study have already been useful in identifying defence-related genes as well as providing gene information for other studies looking at processes such as ROS regulation as well as hypoxia in avocado roots. Our EST data will aid in the elucidation of the avocado transcriptome and identification of markers for improved rootstock breeding and

  6. EST sequencing and gene expression profiling of defence-related genes from Persea americana infected with Phytophthora cinnamomi.

    PubMed

    Mahomed, Waheed; Berg, Noëlani van den

    2011-11-23

    Avocado (Persea americana) belongs to the Lauraceae family and is an important commercial fruit crop in over 50 countries. The most serious pathogen affecting avocado production is Phytophthora cinnamomi which causes Phytophthora root rot (PRR). Root pathogens such as P. cinnamomi and their interactions with hosts are poorly understood and despite the importance of both the avocado crop and the effect Phytophthora has on its cultivation, there is a lack of molecular knowledge underpinning our understanding of defence strategies against the pathogen. In order to initiate a better understanding of host-specific defence we have generated EST data using 454 pyrosequencing and profiled nine defence-related genes from Pc-infected avocado roots. 2.0 Mb of data was generated consisting of ~10,000 reads on a single lane of the GS FLX platform. Using the Newbler assembler 371 contigs were assembled, of which 367 are novel for Persea americana. Genes were classified according to Gene Ontology terms. In addition to identifying root-specific ESTs we were also able to identify and quantify the expression of nine defence-related genes that were differentially regulated in response to P. cinnamomi. Genes such as metallothionein, thaumatin and the pathogenesis related PsemI, mlo and profilin were found to be differentially regulated. This is the first study in elucidating the avocado root transcriptome as well as identifying defence responses of avocado roots to the root pathogen P. cinnamomi. Our data is currently the only EST data that has been generated for avocado rootstocks, and the ESTs identified in this study have already been useful in identifying defence-related genes as well as providing gene information for other studies looking at processes such as ROS regulation as well as hypoxia in avocado roots. Our EST data will aid in the elucidation of the avocado transcriptome and identification of markers for improved rootstock breeding and screening. The characterization of

  7. Comparative expression profiling in grape (Vitis vinifera) berries derived from frequency analysis of ESTs and MPSS signatures.

    PubMed

    Iandolino, Alberto; Nobuta, Kan; da Silva, Francisco Goes; Cook, Douglas R; Meyers, Blake C

    2008-05-12

    Vitis vinifera (V. vinifera) is the primary grape species cultivated for wine production, with an industry valued annually in the billions of dollars worldwide. In order to sustain and increase grape production, it is necessary to understand the genetic makeup of grape species. Here we performed mRNA profiling using Massively Parallel Signature Sequencing (MPSS) and combined it with available Expressed Sequence Tag (EST) data. These tag-based technologies, which do not require a priori knowledge of genomic sequence, are well-suited for transcriptional profiling. The sequence depth of MPSS allowed us to capture and quantify almost all the transcripts at a specific stage in the development of the grape berry. The number and relative abundance of transcripts from stage II grape berries was defined using Massively Parallel Signature Sequencing (MPSS). A total of 2,635,293 17-base and 2,259,286 20-base signatures were obtained, representing at least 30,737 and 26,878 distinct sequences. The average normalized abundance per signature was approximately 49 TPM (Transcripts Per Million). Comparisons of the MPSS signatures with available Vitis species' ESTs and a unigene set demonstrated that 6,430 distinct contigs and 2,190 singletons have a perfect match to at least one MPSS signature. Among the matched sequences, ESTs were identified from tissues other than berries or from berries at different developmental stages. Additional MPSS signatures not matching to known grape ESTs can extend our knowledge of the V. vinifera transcriptome, particularly when these data are used to assist in annotation of whole genome sequences from Vitis vinifera. The MPSS data presented here not only achieved a higher level of saturation than previous EST based analyses, but in doing so, expand the known set of transcripts of grape berries during the unique stage in development that immediately precedes the onset of ripening. The MPSS dataset also revealed evidence of antisense expression not

  8. Photoluminescence and scintillation properties of Ce-doped Sr2(Gd1-xLux)8(SiO4)6O2 (x = 0.1, 0.2, 0.4, 0.5, 0.6) crystals

    NASA Astrophysics Data System (ADS)

    Igashira, Takuya; Kawano, Naoki; Okada, Go; Kawaguchi, Noriaki; Yanagida, Takayuki

    2018-05-01

    Apatite crystals with chemical compositions of 0.5% Ce-doped Sr2(Gd1-xLux)8(SiO4)6O2 (x = 0.1, 0.2, 0.4, 0.5, 0.6) were synthesized by the Floating Zone method, and then we evaluated their photoluminescence (PL) and scintillation properties. All the Ce-doped samples exhibited PL and scintillation with an intense broad emission in 400-550 nm in which the origin was attributed to the 5d-4f transition of Ce3+, and the emission peak became broader with increasing the concentration of Lu3+. Both PL and scintillation decay time profiles were best-approximated by a sum of two exponential decay functions, and the origin of slower component was attributed to the 5d-4f transition of Ce3+. In the X-ray induced afterglow measurements, the Ce-doped Sr2(Gd0.4Lu0.6)8(SiO4)6O2 sample exhibited the lowest afterglow level. Furthermore, the Ce-doped Sr2(Gd0.5Lu0.5)8(SiO4)6O2 and Sr2(Gd0.4Lu0.6)8(SiO4)6O2 samples showed a clear full energy deposited peak under 5.5 MeV 241Am α-ray irradiation, and the estimated absolute scintillation light yields were around 290 and 1300 ph/5.5 MeV-α, respectively.

  9. Determinação de regiões de órbitas diretas estáveis ao redor da Lua

    NASA Astrophysics Data System (ADS)

    de Melo, C. F.; Winter, O. C.; Vieira Neto, E.

    2003-08-01

    Neste Trabalho estamos investigando regiões do sistema Terra-Lua que contêm órbitas diretas estáveis ao redor da Lua visando a utilização destas órbitas em futuras missões de veículos espaciais como alternativas de trajetórias com baixo custo de manutenção. Adotando-se o problema restrito de três corpos, Terra-Lua-partícula, a localização e a extensão destas regiões de estabilidade foram investigadas numericamente considerando como estável toda órbita que permanece ao redor a Lua por, no mínimo, 1000 dias com energia de dois corpos da partícula em relação à Lua negativa. A estabilidade de tais regiões está associada a duas famílias de órbitas periódicas simples H1 e H2 e a órbitas quase-periódicas associadas a elas. Uma vez identificadas as regiões de estabilidade passamos a analisá-las introduzindo, paulatinamente, outras interações relevantes ao sistema como as perturbações do Sol (via problema restrito de quatro corpos), das marés, da pressão de radiação e do achatamento terrestre. Os resultados encontrados até o momento mostram que a perturbação do Sol é a única que reduz significativamente o tamanho das regiões de estabilidade. Também estamos investigando o comportamento de tais regiões quando características intrínsecas do sistema como as excentricidades das órbitas da Terra e da Lua e a inclinação da órbita Lua são consideradas. Com este estudo estamos reunindo informações que nos permitirão compreender a evolução das regiões de estabilidade no sistema Terra-Lua, bem como estabelecer parâmetros adequados para a utilização das trajetórias estáveis em futuras missões espaciais. Agradecimentos: Este projeto conta com o apoio do CNPq, da Capes e da Fapesp.

  10. Characterization of expressed sequence tags (ESTs) of pigeonpea (Cajanus cajan L.) and functional validation of selected genes for abiotic stress tolerance in Arabidopsis thaliana.

    PubMed

    Priyanka, B; Sekhar, K; Sunita, T; Reddy, V D; Rao, Khareedu Venkateswara

    2010-03-01

    Pigeonpea, a major grain legume crop with remarkable drought tolerance traits, has been used for the isolation of stress-responsive genes. Herein, we report generation of ESTs, transcript profiles of selected genes and validation of candidate genes obtained from the subtracted cDNA libraries of pigeonpea plants subjected to PEG/water-deficit stress conditions. Cluster analysis of 124 selected ESTs yielded 75 high-quality ESTs. Homology searches disclosed that 55 ESTs share significant similarity with the known/putative proteins or ESTs available in the databases. These ESTs were characterized and genes relevant to the specific physiological processes were identified. Of the 75 ESTs obtained from the cDNA libraries of drought-stressed plants, 20 ESTs proved to be unique to the pigeonpea. These sequences are envisaged to serve as a potential source of stress-inducible genes of the drought stress-response transcriptome, and hence may be used for deciphering the mechanism of drought tolerance of the pigeonpea. Expression profiles of selected genes revealed increased levels of m-RNA transcripts in pigeonpea plants subjected to different abiotic stresses. Transgenic Arabidopsis lines, expressing Cajanus cajan hybrid-proline-rich protein (CcHyPRP), C. cajan cyclophilin (CcCYP) and C. cajan cold and drought regulatory (CcCDR) genes, exhibited marked tolerance, increased plant biomass and enhanced photosynthetic rates under PEG/NaCl/cold/heat stress conditions. This study represents the first report dealing with the isolation of drought-specific ESTs, transcriptome analysis and functional validation of drought-responsive genes of the pigeonpea. These genes, as such, hold promise for engineering crop plants bestowed with tolerance to major abiotic stresses.

  11. Analyses of Thinopyrum bessarabicum, Th. elongation and Th. junceum chromosomes using EST-SSR markers

    USDA-ARS?s Scientific Manuscript database

    Wild Thinopyrum grasses serve as important gene pools for forage and cereal crops. Knowledge of their chromosome organizations is pivotal for efficient utilization of this important gene pool in germplasm enhancement programs. EST-SSR markers for Th. bessarabicum, Th. elongatum and Th. junceum chr...

  12. Est10: A Novel Alkaline Esterase Isolated from Bovine Rumen Belonging to the New Family XV of Lipolytic Enzymes

    PubMed Central

    Rodríguez, María Cecilia; Loaces, Inés; Amarelle, Vanesa; Senatore, Daniella; Iriarte, Andrés; Fabiano, Elena; Noya, Francisco

    2015-01-01

    A metagenomic fosmid library from bovine rumen was used to identify clones with lipolytic activity. One positive clone was isolated. The gene responsible for the observed phenotype was identified by in vitro transposon mutagenesis and sequencing and was named est10. The 367 amino acids sequence harbors a signal peptide, the conserved secondary structure arrangement of alpha/beta hydrolases, and a GHSQG pentapeptide which is characteristic of esterases and lipases. Homology based 3D-modelling confirmed the conserved spatial orientation of the serine in a nucleophilic elbow. By sequence comparison, Est10 is related to hydrolases that are grouped into the non-specific Pfam family DUF3089 and to other characterized esterases that were recently classified into the new family XV of lipolytic enzymes. Est10 was heterologously expressed in Escherichia coli as a His-tagged fusion protein, purified and biochemically characterized. Est10 showed maximum activity towards C4 aliphatic chains and undetectable activity towards C10 and longer chains which prompted its classification as an esterase. However, it was able to efficiently catalyze the hydrolysis of aryl esters such as methyl phenylacetate and phenyl acetate. The optimum pH of this enzyme is 9.0, which is uncommon for esterases, and it exhibits an optimal temperature at 40°C. The activity of Est10 was inhibited by metal ions, detergents, chelating agents and additives. We have characterized an alkaline esterase produced by a still unidentified bacterium belonging to a recently proposed new family of esterases. PMID:25973851

  13. Est10: A Novel Alkaline Esterase Isolated from Bovine Rumen Belonging to the New Family XV of Lipolytic Enzymes.

    PubMed

    Rodríguez, María Cecilia; Loaces, Inés; Amarelle, Vanesa; Senatore, Daniella; Iriarte, Andrés; Fabiano, Elena; Noya, Francisco

    2015-01-01

    A metagenomic fosmid library from bovine rumen was used to identify clones with lipolytic activity. One positive clone was isolated. The gene responsible for the observed phenotype was identified by in vitro transposon mutagenesis and sequencing and was named est10. The 367 amino acids sequence harbors a signal peptide, the conserved secondary structure arrangement of alpha/beta hydrolases, and a GHSQG pentapeptide which is characteristic of esterases and lipases. Homology based 3D-modelling confirmed the conserved spatial orientation of the serine in a nucleophilic elbow. By sequence comparison, Est10 is related to hydrolases that are grouped into the non-specific Pfam family DUF3089 and to other characterized esterases that were recently classified into the new family XV of lipolytic enzymes. Est10 was heterologously expressed in Escherichia coli as a His-tagged fusion protein, purified and biochemically characterized. Est10 showed maximum activity towards C4 aliphatic chains and undetectable activity towards C10 and longer chains which prompted its classification as an esterase. However, it was able to efficiently catalyze the hydrolysis of aryl esters such as methyl phenylacetate and phenyl acetate. The optimum pH of this enzyme is 9.0, which is uncommon for esterases, and it exhibits an optimal temperature at 40 °C. The activity of Est10 was inhibited by metal ions, detergents, chelating agents and additives. We have characterized an alkaline esterase produced by a still unidentified bacterium belonging to a recently proposed new family of esterases.

  14. Secondary mirror system for the European Solar Telescope (EST)

    NASA Astrophysics Data System (ADS)

    Cavaller, L.; Siegel, B.; Prieto, G.; Hernandez, E.; Casalta, J. M.; Mercader, J.; Barriga, J.

    2010-07-01

    The European Solar Telescope (EST) is a European collaborative project to build a 4m class solar telescope in the Canary Islands, which is now in its design study phase. The telescope will provide diffraction limited performance for several instruments observing simultaneously at the Coudé focus at different wavelengths. A multi-conjugated adaptive optics system composed of a tip-tilt mirror and several deformable mirrors will be integrated in the telescope optical path. The secondary mirror system is composed of the mirror itself (Ø800mm), the alignment drives and the cooling system needed to remove the solar heat load from the mirror. During the design study the feasibility to provide fast tip-tilt capabilities at the secondary mirror to work as the adaptive optics tip-tilt mirror is also being evaluated.

  15. Pharmacogénétique: qu'en est-il au Maroc?

    PubMed Central

    Idrissi, Meryem Janati; Ouldim, Karim; Amarti, Afaf; El Hassouni, Mohamed; Khabbal, Youssef

    2013-01-01

    La pharmacogénétique est l’étude de l'influence des variations génétiques interindividuelles sur la réponse aux médicaments, avec le but d'améliorer la prise en charge des patients en visant une médecine personnalisée. Au fait le génome de deux personnes ne diffère que par 0.1% des 3.2 milliards de paires de bases, ce qui implique les effets indésirables des médicaments, qui ont un très important impact sur le plan clinique que sur le plan économique. Or cette dernière décennie ces effets indésirables ont pu être évités grâce aux tests pharmacogénétiques. Au Maroc, la recherche en pharmacogénétique commence à susciter l'intérêt des chercheurs avec quelques études. Une toute première étude en 1986, sur l'acétylation de l'isoniazide chez la population marocaine, suivie par deux autres en 2011 se focalisant sur le métabolisme du tacrolimus et des anti-vitamines K. Ainsi l'espoir maintenant est d'identifier les majoritaires polymorphismes génétiques affectant les patients marocains, afin de leur fournir une prise en charge adaptée. PMID:23785548

  16. C'est La Vie! The Game of Social Life: Using an Intersectionality Approach to Teach About Privilege and Structural Inequality

    ERIC Educational Resources Information Center

    Bramesfeld, Kosha D.; Good, Arla

    2016-01-01

    In this article, we present the results of two studies that evaluated an experiential intersectionality awareness activity, "C'est La Vie: The Game of Social Life." For Study 1 (N = 55), we content analyzed students' short answer responses about inequality written before and after playing "C'est La Vie." Study 2 compared a…

  17. First genetic linkage map of Taraxacum koksaghyz Rodin based on AFLP, SSR, COS and EST-SSR markers.

    PubMed

    Arias, Marina; Hernandez, Monica; Remondegui, Naroa; Huvenaars, Koen; van Dijk, Peter; Ritter, Enrique

    2016-08-04

    Taraxacum koksaghyz Rodin (TKS) has been studied in many occasions as a possible alternative source for natural rubber production of good quality and for inulin production. Some tire companies are already testing TKS tire prototypes. There are also many investigations on the production of bio-fuels from inulin and inulin applications for health improvement and in the food industry. A limited amount of genomic resources exist for TKS and particularly no genetic linkage map is available in this species. We have constructed the first TKS genetic linkage map based on AFLP, COS, SSR and EST-SSR markers. The integrated linkage map with eight linkage groups (LG), representing the eight chromosomes of Russian dandelion, has 185 individual AFLP markers from parent 1, 188 individual AFLP markers from parent 2, 75 common AFLP markers and 6 COS, 1 SSR and 63 EST-SSR loci. Blasting the EST-SSR sequences against known sequences from lettuce allowed a partial alignment of our TKS map with a lettuce map. Blast searches against plant gene databases revealed some homologies with useful genes for downstream applications in the future.

  18. Sensitive in situ monitoring of a recombinant bioluminescent Yersinia enterocolitica reporter mutant in real time on Camembert cheese.

    PubMed

    Maoz, Ariel; Mayr, Ralf; Bresolin, Geraldine; Neuhaus, Klaus; Francis, Kevin P; Scherer, Siegfried

    2002-11-01

    Bioluminescent mutants of Yersinia enterocolitica were generated by transposon mutagenesis using a promoterless, complete lux operon (luxCDABE) derived from Photorhabdus luminescens, and their production of light in the cheese environment was monitored. Mutant B94, which had the lux cassette inserted into an open reading frame of unknown function was used for direct monitoring of Y. enterocolitica cells on cheeses stored at 10 degrees C by quantifying bioluminescence using a photon-counting, intensified charge-coupled device camera. The detection limit on cheese was 200 CFU/cm(2). Bioluminescence of the reporter mutant was significantly regulated by its environment (NaCl, temperature, and cheese), as well as by growth phase, via the promoter the lux operon had acquired upon transposition. At low temperatures, mutant B94 did not exhibit the often-reported decrease of photon emission in older cells. It was not necessary to include either antibiotics or aldehyde in the food matrix in order to gain quantitative, reproducible bioluminescence data. As far as we know, this is the first time a pathogen has been monitored in situ, in real time, in a "real-product" status, and at a low temperature.

  19. Sensitive In Situ Monitoring of a Recombinant Bioluminescent Yersinia enterocolitica Reporter Mutant in Real Time on Camembert Cheese

    PubMed Central

    Maoz, Ariel; Mayr, Ralf; Bresolin, Geraldine; Neuhaus, Klaus; Francis, Kevin P.; Scherer, Siegfried

    2002-01-01

    Bioluminescent mutants of Yersinia enterocolitica were generated by transposon mutagenesis using a promoterless, complete lux operon (luxCDABE) derived from Photorhabdus luminescens, and their production of light in the cheese environment was monitored. Mutant B94, which had the lux cassette inserted into an open reading frame of unknown function was used for direct monitoring of Y. enterocolitica cells on cheeses stored at 10°C by quantifying bioluminescence using a photon-counting, intensified charge-coupled device camera. The detection limit on cheese was 200 CFU/cm2. Bioluminescence of the reporter mutant was significantly regulated by its environment (NaCl, temperature, and cheese), as well as by growth phase, via the promoter the lux operon had acquired upon transposition. At low temperatures, mutant B94 did not exhibit the often-reported decrease of photon emission in older cells. It was not necessary to include either antibiotics or aldehyde in the food matrix in order to gain quantitative, reproducible bioluminescence data. As far as we know, this is the first time a pathogen has been monitored in situ, in real time, in a “real-product” status, and at a low temperature. PMID:12406772

  20. Bioluminescent bioreporter sensing of foodborne toxins

    NASA Astrophysics Data System (ADS)

    Fraley, Amanda C.; Ripp, Steven; Sayler, Gary S.

    2004-06-01

    Histamine is the primary etiological agent in the foodborne disease scombrotoxicosis, one of the most common food toxicities related to fish consumption. Procedures for detecting histamine in fish products are available, but are often too expensive or too complex for routine use. As an alternative, a bacterial bioluminescent bioreporter has been constructed to develop a biosensor system that autonomously responds to low levels of histamine. The bioreporter contains a promoterless Photorhabdus luminescens lux operon (luxCDABE) fused with the Vibrio anguillarum angR regulatory gene promoter of the anguibactin biosynthetic operon. The bioreporter emitted 1.46 times more bioluminescence than background, 30 minutes after the addition of 100mM histamine. However, specificity was not optimal, as this biosensor generated significant bioluminescence in the presence of L-proline and L-histidine. As a means towards improving histamine specificity, the promoter region of a histamine oxidase gene from Arthrobacter globiformis was cloned upstream of the promotorless lux operon from Photorhabdus luminescens. This recently constructed whole-cell, lux-based bioluminescent bioreporter is currently being tested for optimal performance in the presence of histamine in order to provide a rapid, simple, and inexpensive model sensor for the detection of foodborne toxins.

  1. The Effect of Sunlight in Parenchyma Pith Cells Diameter of Manihot esculenta

    NASA Astrophysics Data System (ADS)

    Susanti, D.; Aziz, D. N.; Astuti, W.; Nuraeni, E.

    2017-03-01

    Sunlight is one of the factors that effect on the grow of a plant. Manihot esculenta is one of the plants that easily found in Indonesia because its role as staple food. The aim of this research is to know the correlation between sunlight the grow of parenchyma pith cells diameter of Manihot esculenta. Independent variable in this research is sunlight, and dependent variable is the parenchyma pith cells diameter of Manihot esculenta. Data was collected is in qualitative and quantitative form. Qualitative data gotten gained by morphology observation. The parenchyma pith cells of Manihot esculenta that is affected by sunlight in 1310 x 10 Lux, morphologically has hexagon, cell walls thick, solid state, and regular composition. Meanwhile, the parenchyma pith cells that has less sunlight (363 x 10 Lux) has a hexagon shape, thin cell walls thin, soft state, and irregular composition. Qualitative data suported by quantitative data. The size of parenchyma pith cells diameter that is affected by sunlight in 1310 x 10 Lux 96,4 µm. While, the stem parenchyma pith cells diameter empulur that has less sunlight (363 x 10 Lux) is 129,8 µm.

  2. Facilitation of alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate receptor transmission in the suprachiasmatic nucleus by aniracetam enhances photic responses of the biological clock in rodents.

    PubMed

    Moriya, Takahiro; Ikeda, Masayuki; Teshima, Koji; Hara, Reiko; Kuriyama, Koji; Yoshioka, Tohru; Allen, Charles N; Shibata, Shigenobu

    2003-05-01

    This study was designed to test whether the alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA) receptor-facilitating drug, aniracetam, could potentiate photic responses of the biological clock in the suprachiasmatic nucleus (SCN) of rodents. Using the whole-cell patch technique, we first demonstrated that AMPA currents elicited by either local AMPA application or optic chiasm stimulation were augmented by aniracetam in the neurons of the SCN. The AMPA application-elicited increase of intracellular Ca2+ concentration in SCN slices was also enhanced by aniracetam treatment. The systemic injection of aniracetam dose-dependently (10-100 mg/kg) potentiated the phase delay in behavioral rhythm induced by brief light exposure of low intensity (3 lux) but not high intensity (10 or 60 lux) during early subjective night. Under the blockade of NMDA receptors by (+) MK801, aniracetam failed to potentiate a light (3 lux)-induced phase delay in behavioral rhythm. Aniracetam increased the photic induction of c-Fos protein in the SCN that was elicited by low intensity light exposure (3 lux). These results suggest that AMPA receptor-mediated responses facilitated by aniracetam can explain enhanced photic responses of the biological clock in the SCN of rodents.

  3. Normal Telomere Length Maintenance in Saccharomyces cerevisiae Requires Nuclear Import of the Ever Shorter Telomeres 1 (Est1) Protein via the Importin Alpha Pathway

    PubMed Central

    Hawkins, Charlene

    2014-01-01

    The Est1 (ever shorter telomeres 1) protein is an essential component of yeast telomerase, a ribonucleoprotein complex that restores the repetitive sequences at chromosome ends (telomeres) that would otherwise be lost during DNA replication. Previous work has shown that the telomerase RNA component (TLC1) transits through the cytoplasm during telomerase biogenesis, but mechanisms of protein import have not been addressed. Here we identify three nuclear localization sequences (NLSs) in Est1p. Mutation of the most N-terminal NLS in the context of full-length Est1p reduces Est1p nuclear localization and causes telomere shortening—phenotypes that are rescued by fusion with the NLS from the simian virus 40 (SV40) large-T antigen. In contrast to that of the TLC1 RNA, Est1p nuclear import is facilitated by Srp1p, the yeast homolog of importin α. The reduction in telomere length observed at the semipermissive temperature in a srp1 mutant strain is rescued by increased Est1p expression, consistent with a defect in Est1p nuclear import. These studies suggest that at least two nuclear import pathways are required to achieve normal telomere length homeostasis in yeast. PMID:24906415

  4. Development and use of EST-SSR markers for assessing genetic diversity in the brown planthopper (Nilaparvata lugens Stål).

    PubMed

    Jing, S; Liu, B; Peng, L; Peng, X; Zhu, L; Fu, Q; He, G

    2012-02-01

    To assess genetic diversity in populations of the brown planthopper (Nilaparvata lugens Stål) (Homoptera: Delphacidae), we have developed and applied microsatellite, or simple sequence repeat (SSR), markers from expressed sequence tags (ESTs). We found that the brown planthopper clusters of ESTs were rich in SSRs with unique frequencies and distributions of SSR motifs. Three hundred and fifty-one EST-SSR markers were developed and yielded clear bands from samples of four brown planthopper populations. High cross-species transferability of these markers was detected in the closely related planthopper N. muiri. The newly developed EST-SSR markers provided sufficient resolution to distinguish within and among biotypes. Analyses based on SSR data revealed host resistance-based genetic differentiation among different brown planthopper populations; the genetic diversity of populations feeding on susceptible rice varieties was lower than that of populations feeding on resistant rice varieties. This is the first large-scale development of brown planthopper SSR markers, which will be useful for future molecular genetics and genomics studies of this serious agricultural pest.

  5. Development of EST-derived microsatellite markers in the aquatic macrophyte Ranunculus bungei (Ranunculaceae)1

    PubMed Central

    Wu, Zhigang; Wu, Jinwei; Wang, Yalin; Hou, Hongwei

    2017-01-01

    Premise of the study: Microsatellite or simple sequence repeat (SSR) markers were developed to investigate the influence of ecological factors on gene flow and spatial genetic structuring of the submerged plant Ranunculus bungei (Ranunculaceae), which is regarded as an important species for understanding how plants adapt to an aquatic environment. Methods and Results: Twenty-two microsatellite loci were identified from an expressed sequence tag (EST) library. The number of alleles per locus ranged from one to five, and the expected heterozygosity varied from 0.0 to 0.5 in four Chinese populations of R. bungei. Fourteen loci were polymorphic and significantly deviated from Hardy–Weinberg equilibrium. All of the loci were found to be amplifiable in two other species of Ranunculus section Batrachium, and cross-amplification in six riparian and aquatic species of Ranunculaceae was also partially successful. Conclusions: These novel EST-SSR markers will be useful for ecological and evolutionary studies of R. bungei as well as related species. PMID:28791205

  6. Light-Emitting Diodes and Cool White Fluorescent Light Similarly Suppress Pineal Gland Melatonin and Maintain Retinal Function and Morphology in the Rat. Part 1

    NASA Technical Reports Server (NTRS)

    Holley, Daniel C.; Heeke, D.; Mele, G.

    1999-01-01

    Currently, the light sources most commonly used in animal habitat lighting are cool white fluorescent or incandescent lamps. We evaluated a novel light-emitting diode (LED) light source for use in animal habitat lighting by comparing its effectiveness to cool white fluorescent light (CWF) in suppressing pineal gland melatonin and maintaining normal retinal physiology and morphology in the rat. Results of pineal melatonin suppression experiments showed equal suppression of pineal melatonin concentrations for LED light and CWF light at five different light illuminances (100, 40, 10, 1 and 0.1 lux). There were no significant differences in melatonin suppression between LED and CWF light when compared to unexposed controls. Retinal physiology was evaluated using electroretinography. Results show no differences in a-wave implicit times and amplitudes or b-wave implicit times and amplitudes between 100-lux LED-exposed rats and 100-lux CWF-exposed rats. Results of retinal histology assessment show no differences in retinal thickness rod outer segment length and number of rod nuclei between rats exposed to 100-lux LED and 100-lux CWF for days. Furthermore, the retinal pigmented epithelium and rod outer segments of all eyes observed were in good condition and of normal thickness. This study indicates that LED light does not cause retinal damage and can suppress pineal melatonin at similar intensities as a conventional CWF light source. These data suggest that LED light sources may be suitable replacements for conventional light sources used in the lighting of rodent vivariums while providing many mechanical and economical advantages.

  7. Accuracy of a smartphone to test laryngoscope's light and an audit to our laryngoscopes using an ISO standard.

    PubMed

    Machado, Diogo Alcino de Abreu Ribeiro Carvalho; Esteves, Dina da Assunção Azevedo; Branca, Pedro Manuel Araújo de Sousa

    Laryngoscope is a key tool in anesthetic practice. Direct laryngoscopy is a crucial moment and inadequate laryngoscope's light can lead to catastrophic consequences. From our experience laryngoscope's light is assessed in a subjective manner and we believe a more precise evaluation should be used. Our objective is to compare the accuracy of a smartphone compared to a lux meter. Secondly we audited our Operating Room laryngoscopes. We designed a pragmatic study, using as primary outcome the accuracy of a smartphone compared to the lux meter. Further we audited with both the lux meter and the smartphone all laryngoscopes and blades ready to use in our Operating Rooms, using the International Standard form the International Organization for Standardization. For primary outcome we found no significant difference between devices. Our audit showed that only 2 in 48 laryngoscopes complied with the ISO norm. When comparing the measurements between the lux meter and the smartphone we found no significant difference. Ideally every laryngoscope should perform as required. We believe all laryngoscopes should have a practical but reliable and objective test prior to its utilization. Our results suggest the smartphone was accurate enough to be used as a lux meter to test laryngoscope's light. Audit results showing only 4% comply with the ISO standard are consistent with other studies. The tested smartphone has enough accuracy to perform light measurement in laryngoscopes. We believe this is a step further to perform an objective routine check to laryngoscope's light. Copyright © 2016. Published by Elsevier Editora Ltda.

  8. Single-session manualized ego state therapy (EST) for combat stress injury, PTSD, and ASD, part 1: the theory.

    PubMed

    Barabasz, Arreed F; Barabasz, Marianne; Watkins, John G

    2011-01-01

    Ego state therapy (EST) evolved from a psychodynamic understanding of personality as a product of an individual's ego states to a conceptualization of how ego-energized and object-energized elements are bound together to cope with a traumatic event. Neurobiological studies now substantiate Watkins's war neuroses conceptualizations. Because of their severity, trauma memories are encoded in the subcortical-subconscious brain regions that are accessed by the single-session manualized EST procedure but not by the popular cognitive-behavioral management therapies. The imprint of the trauma is not accessible or resolvable by such top-down verbal understanding or reframing; EST is a bottom-up therapy. Abreactive hypnosis facilitates ego state expression at physiologically and psychologically intense levels sufficient to activate subcortical processes to release affect in the presence of the therapist, who adds ego strength to the patient. This is followed by interpretation and reintegration. The result is a reconstructed personality that is adaptive and resilient.

  9. Development of EST Intron-Targeting SNP Markers for Panax ginseng and Their Application to Cultivar Authentication.

    PubMed

    Wang, Hongtao; Li, Guisheng; Kwon, Woo-Saeng; Yang, Deok-Chun

    2016-06-04

    Panax ginseng is one of the most valuable medicinal plants in the Orient. The low level of genetic variation has limited the application of molecular markers for cultivar authentication and marker-assisted selection in cultivated ginseng. To exploit DNA polymorphism within ginseng cultivars, ginseng expressed sequence tags (ESTs) were searched against the potential intron polymorphism (PIP) database to predict the positions of introns. Intron-flanking primers were then designed in conserved exon regions and used to amplify across the more variable introns. Sequencing results showed that single nucleotide polymorphisms (SNPs), as well as indels, were detected in four EST-derived introns, and SNP markers specific to "Gopoong" and "K-1" were first reported in this study. Based on cultivar-specific SNP sites, allele-specific polymerase chain reaction (PCR) was conducted and proved to be effective for the authentication of ginseng cultivars. Additionally, the combination of a simple NaOH-Tris DNA isolation method and real-time allele-specific PCR assay enabled the high throughput selection of cultivars from ginseng fields. The established real-time allele-specific PCR assay should be applied to molecular authentication and marker assisted selection of P. ginseng cultivars, and the EST intron-targeting strategy will provide a potential approach for marker development in species without whole genomic DNA sequence information.

  10. Cyclic AMP Receptor Protein Regulates Pheromone-Mediated Bioluminescence at Multiple Levels in Vibrio fischeri ES114

    PubMed Central

    Lyell, Noreen L.; Colton, Deanna M.; Bose, Jeffrey L.; Tumen-Velasquez, Melissa P.; Kimbrough, John H.

    2013-01-01

    Bioluminescence in Vibrio fischeri ES114 is activated by autoinducer pheromones, and this regulation serves as a model for bacterial cell-cell signaling. As in other bacteria, pheromone concentration increases with cell density; however, pheromone synthesis and perception are also modulated in response to environmental stimuli. Previous studies suggested that expression of the pheromone-dependent bioluminescence activator LuxR is regulated in response to glucose by cyclic AMP (cAMP) receptor protein (CRP) (P. V. Dunlap and E. P. Greenberg, J. Bacteriol. 164:45–50, 1985; P. V. Dunlap and E. P. Greenberg, J. Bacteriol. 170:4040–4046, 1988; P. V. Dunlap, J. Bacteriol. 171:1199–1202, 1989; and W. F. Friedrich and E. P. Greenberg, Arch. Microbiol. 134:87–91, 1983). Consistent with this model, we found that bioluminescence in V. fischeri ES114 is modulated by glucose and stimulated by cAMP. In addition, a Δcrp mutant was ∼100-fold dimmer than ES114 and did not increase luminescence in response to added cAMP, even though cells lacking crp were still metabolically capable of producing luminescence. We further discovered that CRP regulates not only luxR but also the alternative pheromone synthase gene ainS. We found that His-tagged V. fischeri CRP could bind sequences upstream of both luxR and ainS, supporting bioinformatic predictions of direct regulation at both promoters. Luminescence increased in response to cAMP if either the ainS or luxR system was under native regulation, suggesting cAMP-CRP significantly increases luminescence through both systems. Finally, using transcriptional reporters in transgenic Escherichia coli, we elucidated two additional regulatory connections. First, LuxR-independent basal transcription of the luxI promoter was enhanced by CRP. Second, the effect of CRP on the ainS promoter depended on whether the V. fischeri regulatory gene litR was also introduced. These results suggest an integral role for CRP in pheromone signaling that

  11. Multiple Candidate Effectors from the Oomycete Pathogen Hyaloperonospora arabidopsidis Suppress Host Plant Immunity

    PubMed Central

    Fabro, Georgina; Steinbrenner, Jens; Coates, Mary; Ishaque, Naveed; Baxter, Laura; Studholme, David J.; Körner, Evelyn; Allen, Rebecca L.; Piquerez, Sophie J. M.; Rougon-Cardoso, Alejandra; Greenshields, David; Lei, Rita; Badel, Jorge L.; Caillaud, Marie-Cecile; Sohn, Kee-Hoon; Van den Ackerveken, Guido; Parker, Jane E.; Beynon, Jim; Jones, Jonathan D. G.

    2011-01-01

    Oomycete pathogens cause diverse plant diseases. To successfully colonize their hosts, they deliver a suite of effector proteins that can attenuate plant defenses. In the oomycete downy mildews, effectors carry a signal peptide and an RxLR motif. Hyaloperonospora arabidopsidis (Hpa) causes downy mildew on the model plant Arabidopsis thaliana (Arabidopsis). We investigated if candidate effectors predicted in the genome sequence of Hpa isolate Emoy2 (HaRxLs) were able to manipulate host defenses in different Arabidopsis accessions. We developed a rapid and sensitive screening method to test HaRxLs by delivering them via the bacterial type-three secretion system (TTSS) of Pseudomonas syringae pv tomato DC3000-LUX (Pst-LUX) and assessing changes in Pst-LUX growth in planta on 12 Arabidopsis accessions. The majority (∼70%) of the 64 candidates tested positively contributed to Pst-LUX growth on more than one accession indicating that Hpa virulence likely involves multiple effectors with weak accession-specific effects. Further screening with a Pst mutant (ΔCEL) showed that HaRxLs that allow enhanced Pst-LUX growth usually suppress callose deposition, a hallmark of pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI). We found that HaRxLs are rarely strong avirulence determinants. Although some decreased Pst-LUX growth in particular accessions, none activated macroscopic cell death. Fewer HaRxLs conferred enhanced Pst growth on turnip, a non-host for Hpa, while several reduced it, consistent with the idea that turnip's non-host resistance against Hpa could involve a combination of recognized HaRxLs and ineffective HaRxLs. We verified our results by constitutively expressing in Arabidopsis a sub-set of HaRxLs. Several transgenic lines showed increased susceptibility to Hpa and attenuation of Arabidopsis PTI responses, confirming the HaRxLs' role in Hpa virulence. This study shows TTSS screening system provides a useful tool to test whether candidate

  12. Genetic Diversity and Association of EST-SSR and SCoT Markers with Rust Traits in Orchardgrass (Dactylis glomerata L.).

    PubMed

    Yan, Haidong; Zhang, Yu; Zeng, Bing; Yin, Guohua; Zhang, Xinquan; Ji, Yang; Huang, Linkai; Jiang, Xiaomei; Liu, Xinchun; Peng, Yan; Ma, Xiao; Yan, Yanhong

    2016-01-08

    Orchardgrass (Dactylis glomerata L.), is a well-known perennial forage species; however, rust diseases have caused a noticeable reduction in the quality and production of orchardgrass. In this study, genetic diversity was assessed and the marker-trait associations for rust were examined using 18 EST-SSR and 21 SCoT markers in 75 orchardgrass accessions. A high level of genetic diversity was detected in orchardgrass with an average genetic diversity index of 0.369. For the EST-SSR and SCoT markers, 164 and 289 total bands were obtained, of which 148 (90.24%) and 272 (94.12%) were polymorphic, respectively. Results from an AMOVA analysis showed that more genetic variance existed within populations (87.57%) than among populations (12.43%). Using a parameter marker index, the efficiencies of the EST-SSR and SCoT markers were compared to show that SCoTs have higher marker efficiency (8.07) than EST-SSRs (4.82). The results of a UPGMA cluster analysis and a STRUCTURE analysis were both correlated with the geographic distribution of the orchardgrass accessions. Linkage disequilibrium analysis revealed an average r² of 0.1627 across all band pairs, indicating a high extent of linkage disequilibrium in the material. An association analysis between the rust trait and 410 bands from the EST-SSR and SCoT markers using TASSEL software revealed 20 band panels were associated with the rust trait in both 2011 and 2012. The 20 bands obtained from association analysis could be used in breeding programs for lineage selection to prevent great losses of orchardgrass caused by rust, and provide valuable information for further association mapping using this collection of orchardgrass.

  13. In silico search, characterization and validation of new EST-SSR markers in the genus Prunus.

    PubMed

    Sorkheh, Karim; Prudencio, Angela S; Ghebinejad, Azim; Dehkordi, Mehrana Kohei; Erogul, Deniz; Rubio, Manuel; Martínez-Gómez, Pedro

    2016-07-07

    Simple sequence repeats (SSRs) are defined as sequence repeat units between 1 and 6 bp that occur in both coding and non-coding regions abundant in eukaryotic genomes, which may affect the expression of genes. In this study, expressed sequence tags (ESTs) of eight Prunus species were analyzed for in silico mining of EST-SSRs, protein annotation, and open reading frames (ORFs), and the identification of codon repetitions. A total of 316 SSRs were identified using MISA software. Dinucleotide SSR motifs (26.31 %) were found to be the most abundant type of repeats, followed by tri- (14.58 %), tetra- (0.53 %), and penta- (0.27 %) nucleotide motifs. An attempt was made to design primer pairs for 316 identified SSRs but these were successful for only 175 SSR sequences. The positions of SSRs with respect to ORFs were detected, and annotation of sequences containing SSRs was performed to assign function to each sequence. SSRs were also characterized (in terms of position in the reference genome and associated gene) using the two available Prunus reference genomes (mei and peach). Finally, 38 SSR markers were validated across peach, almond, plum, and apricot genotypes. This validation showed a higher transferability level of EST-SSR developed in P. mume (mei) in comparison with the rest of species analyzed. Findings will aid analysis of functionally important molecular markers and facilitate the analysis of genetic diversity.

  14. Construction of a cDNA library from female adult of Toxocara canis, and analysis of EST and immune-related genes expressions.

    PubMed

    Zhou, Rongqiong; Xia, Qingyou; Huang, Hancheng; Lai, Min; Wang, Zhenxin

    2011-10-01

    Toxocara canis is a widespread intestinal nematode parasite of dogs, which can also cause disease in humans. We employed an expressed sequence tag (EST) strategy in order to study gene-expression including development, digestion and reproduction of T. canis. ESTs provided a rapid way to identify genes, particularly in organisms for which we have very little molecular information. In this study, a cDNA library was constructed from a female adult of T. canis and 215 high-quality ESTs from 5'-ends of the cDNA clones representing 79 unigenes were obtained. The titer of the primary cDNA library was 1.83×10(6)pfu/mL with a recombination rate of 99.33%. Most of the sequences ranged from 300 to 900bp with an average length of 656bp. Cluster analysis of these ESTs allowed identification of 79 unique sequences containing 28 contigs and 51 singletons. BLASTX searches revealed that 18 unigenes (22.78% of the total) or 70 ESTs (32.56% of the total) were novel genes that had no significant matches to any protein sequences in the public databases. The rest of the 61 unigenes (77.22% of the total) or 145 ESTs (67.44% of the total) were closely matched to the known genes or sequences deposited in the public databases. These genes were classified into seven groups based on their known or putative biological functions. We also confirmed the gene expression patterns of several immune-related genes using RT-PCR examination. This work will provide a valuable resource for the further investigations in the stage-, sex- and tissue-specific gene transcription or expression. Copyright © 2011. Published by Elsevier Inc.

  15. First genetic linkage map of Taraxacum koksaghyz Rodin based on AFLP, SSR, COS and EST-SSR markers

    PubMed Central

    Arias, Marina; Hernandez, Monica; Remondegui, Naroa; Huvenaars, Koen; van Dijk, Peter; Ritter, Enrique

    2016-01-01

    Taraxacum koksaghyz Rodin (TKS) has been studied in many occasions as a possible alternative source for natural rubber production of good quality and for inulin production. Some tire companies are already testing TKS tire prototypes. There are also many investigations on the production of bio-fuels from inulin and inulin applications for health improvement and in the food industry. A limited amount of genomic resources exist for TKS and particularly no genetic linkage map is available in this species. We have constructed the first TKS genetic linkage map based on AFLP, COS, SSR and EST-SSR markers. The integrated linkage map with eight linkage groups (LG), representing the eight chromosomes of Russian dandelion, has 185 individual AFLP markers from parent 1, 188 individual AFLP markers from parent 2, 75 common AFLP markers and 6 COS, 1 SSR and 63 EST-SSR loci. Blasting the EST-SSR sequences against known sequences from lettuce allowed a partial alignment of our TKS map with a lettuce map. Blast searches against plant gene databases revealed some homologies with useful genes for downstream applications in the future. PMID:27488242

  16. An EST dataset for Metasequoia glyptostroboides buds: the first EST resource for molecular genomics studies in Metasequoia.

    PubMed

    Zhao, Ying; Thammannagowda, Shivegowda; Staton, Margaret; Tang, Sha; Xia, Xinli; Yin, Weilun; Liang, Haiying

    2013-03-01

    The "living fossil" Metasequoia glyptostroboides Hu et Cheng, commonly known as dawn redwood or Chinese redwood, is the only living species in the genus and is valued for its essential oil and crude extracts that have great potential for anti-fungal activity. Despite its paleontological significance and economical value as a rare relict species, genomic resources of Metasequoia are very limited. In order to gain insight into the molecular mechanisms behind the formation of reproductive buds and the transition from vegetative phase to reproductive phase in Metasequoia, we performed sequencing of expressed sequence tags from Metasequoia vegetative buds and female buds. By using the 454 pyrosequencing technology, a total of 1,571,764 high-quality reads were generated, among which 733,128 were from vegetative buds and 775,636 were from female buds. These EST reads were clustered and assembled into 114,124 putative unique transcripts (PUTs) with an average length of 536 bp. The 97,565 PUTs that were at least 100 bp in length were functionally annotated by a similarity search against public databases and assigned with Gene Ontology (GO) terms. A total of 59 known floral gene families and 190 isotigs involved in hormone regulation were captured in the dataset. Furthermore, a set of PUTs differentially expressed in vegetative and reproductive buds, as well as SSR motifs and high confidence SNPs, were identified. This is the first large-scale expressed sequence tags ever generated in Metasequoia and the first evidence for floral genes in this critically endangered deciduous conifer species.

  17. Draft Genome Sequence of Rhodobacteraceae Strain PD-2, an Algicidal Bacterium with a Quorum-Sensing System, Isolated from the Marine Microalga Prorocentrum donghaiense

    PubMed Central

    Cui, Zhisong; Xu, Luyan; Sun, Chengjun; Powell, Ryan J.; Hill, Russell T.

    2015-01-01

    Rhodobacteraceae strain PD-2 was isolated from the marine microalga Prorocentrum donghaiense. It has algicidal activity toward its host and could produce N-acylhomoserine lactone signals. Here, we present the draft genome of strain PD-2, which contains 5,227,214 bp with an average GC content of 66.19%. There were 4,864 encoding gene sequences and two clusters of luxI and luxR homologues identified. PMID:25700405

  18. Development of EST Intron-Targeting SNP Markers for Panax ginseng and Their Application to Cultivar Authentication

    PubMed Central

    Wang, Hongtao; Li, Guisheng; Kwon, Woo-Saeng; Yang, Deok-Chun

    2016-01-01

    Panax ginseng is one of the most valuable medicinal plants in the Orient. The low level of genetic variation has limited the application of molecular markers for cultivar authentication and marker-assisted selection in cultivated ginseng. To exploit DNA polymorphism within ginseng cultivars, ginseng expressed sequence tags (ESTs) were searched against the potential intron polymorphism (PIP) database to predict the positions of introns. Intron-flanking primers were then designed in conserved exon regions and used to amplify across the more variable introns. Sequencing results showed that single nucleotide polymorphisms (SNPs), as well as indels, were detected in four EST-derived introns, and SNP markers specific to “Gopoong” and “K-1” were first reported in this study. Based on cultivar-specific SNP sites, allele-specific polymerase chain reaction (PCR) was conducted and proved to be effective for the authentication of ginseng cultivars. Additionally, the combination of a simple NaOH-Tris DNA isolation method and real-time allele-specific PCR assay enabled the high throughput selection of cultivars from ginseng fields. The established real-time allele-specific PCR assay should be applied to molecular authentication and marker assisted selection of P. ginseng cultivars, and the EST intron-targeting strategy will provide a potential approach for marker development in species without whole genomic DNA sequence information. PMID:27271615

  19. Ontology and diversity of transcript-associated microsatellites mined from a globe artichoke EST database

    PubMed Central

    Scaglione, Davide; Acquadro, Alberto; Portis, Ezio; Taylor, Christopher A; Lanteri, Sergio; Knapp, Steven J

    2009-01-01

    Background The globe artichoke (Cynara cardunculus var. scolymus L.) is a significant crop in the Mediterranean basin. Despite its commercial importance and its both dietary and pharmaceutical value, knowledge of its genetics and genomics remains scant. Microsatellite markers have become a key tool in genetic and genomic analysis, and we have exploited recently acquired EST (expressed sequence tag) sequence data (Composite Genome Project - CGP) to develop an extensive set of microsatellite markers. Results A unigene assembly was created from over 36,000 globe artichoke EST sequences, containing 6,621 contigs and 12,434 singletons. Over 12,000 of these unigenes were functionally assigned on the basis of homology with Arabidopsis thaliana reference proteins. A total of 4,219 perfect repeats, located within 3,308 unigenes was identified and the gene ontology (GO) analysis highlighted some GO term's enrichments among different classes of microsatellites with respect to their position. Sufficient flanking sequence was available to enable the design of primers to amplify 2,311 of these microsatellites, and a set of 300 was tested against a DNA panel derived from 28 C. cardunculus genotypes. Consistent amplification and polymorphism was obtained from 236 of these assays. Their polymorphic information content (PIC) ranged from 0.04 to 0.90 (mean 0.66). Between 176 and 198 of the assays were informative in at least one of the three available mapping populations. Conclusion EST-based microsatellites have provided a large set of de novo genetic markers, which show significant amounts of polymorphism both between and within the three taxa of C. cardunculus. They are thus well suited as assays for phylogenetic analysis, the construction of genetic maps, marker-assisted breeding, transcript mapping and other genomic applications in the species. PMID:19785740

  20. Rapid identification of red-flesh loquat cultivars using EST-SSR markers based on manual cultivar identification diagram strategy.

    PubMed

    Li, X Y; Xu, H X; Chen, J W

    2014-04-29

    Manual cultivar identification diagram is a new strategy for plant cultivar identification based on DNA markers, providing information to efficiently separate cultivars. We tested 25 pairs of apple EST-SSR primers for amplification of PCR products from loquat cultivars. These EST-SSR primers provided clear amplification products from the loquat cultivars, with a relatively high transferability rate of 84% to loquat; 11 pairs of primers amplified polymorphic products. After analysis of 24 red-fleshed loquat accessions, we found that only 7 pairs of primers could clearly separate all of them. A cultivar identification diagram of the 24 cultivars was constructed using polymorphic bands from the DNA fingerprints and EST-SSR primers. Any two of the 24 cultivars could be rapidly separated from each other, according to the polymorphic bands from the cultivars; the corresponding primers were marked in the correct position on the cultivar identification diagram. This red-flesh loquat cultivar identification diagram can separate the 24 red-flesh loquat cultivars, which is of benefit for loquat cultivar identification for germplasm management and breeding programs.

  1. Epidermal-skin-test 1,000 (EST-1,000)--a new reconstructed epidermis for in vitro skin corrosivity testing.

    PubMed

    Hoffmann, J; Heisler, E; Karpinski, S; Losse, J; Thomas, D; Siefken, W; Ahr, H-J; Vohr, H-W; Fuchs, H W

    2005-10-01

    The determination of a possible corrosive or irritative potential of certain products and ingredients is necessary for their classification and labeling requirements. Reconstructed skin as a model system provides fundamental advantages to single cell culture testing and leads to promising results as shown by different validation studies (for review: Fentem, J.H., Botham, P.A., 2002. ECVAM's activities in validating alternative tests for skin corrosion and irritation. ATLA 30(Suppl. 2), 61-67). In this study we introduce our new reconstructed epidermis "Epidermal-Skin-Test" (EST-1,000). This fully grown epidermis consists of proliferating as well as differentiating keratinocytes. EST-1,000 shows a high comparability to normal human skin as shown by histological and immunohistochemical data. Characteristic markers (KI-67, CK 1/10/5/14, transglutaminase, collagen IV, involucrin, beta 1 integrin) can be identified easily. The main focus of this work was to characterize EST-1,000 especially with respect to its barrier function by testing several substances of known corrosive potential. Skin corrosion was detected by the cytotoxic effect of the substances on a reconstructed epidermis after short-term application to the stratum corneum. The effect was determined by standard MTT assay and accompanying histological analysis. Hence EST-1,000 shows a very high predictive potential and closes the gap between animal testing and the established full-thickness model Advanced-Skin-Test 2,000 (AST-2,000) (Noll, M., Merkle, M.-L., Kandsberger, M., Matthes, T., Fuchs, H., Graeve, T., 1999. Reconstructed human skin (AST-2,000) as a tool for pharmaco-toxicology. ATLA 27, 302).

  2. ExprAlign - the identification of ESTs in non-model species by alignment of cDNA microarray expression profiles

    PubMed Central

    2009-01-01

    Background Sequence identification of ESTs from non-model species offers distinct challenges particularly when these species have duplicated genomes and when they are phylogenetically distant from sequenced model organisms. For the common carp, an environmental model of aquacultural interest, large numbers of ESTs remained unidentified using BLAST sequence alignment. We have used the expression profiles from large-scale microarray experiments to suggest gene identities. Results Expression profiles from ~700 cDNA microarrays describing responses of 7 major tissues to multiple environmental stressors were used to define a co-expression landscape. This was based on the Pearsons correlation coefficient relating each gene with all other genes, from which a network description provided clusters of highly correlated genes as 'mountains'. We show that these contain genes with known identities and genes with unknown identities, and that the correlation constitutes evidence of identity in the latter. This procedure has suggested identities to 522 of 2701 unknown carp ESTs sequences. We also discriminate several common carp genes and gene isoforms that were not discriminated by BLAST sequence alignment alone. Precision in identification was substantially improved by use of data from multiple tissues and treatments. Conclusion The detailed analysis of co-expression landscapes is a sensitive technique for suggesting an identity for the large number of BLAST unidentified cDNAs generated in EST projects. It is capable of detecting even subtle changes in expression profiles, and thereby of distinguishing genes with a common BLAST identity into different identities. It benefits from the use of multiple treatments or contrasts, and from the large-scale microarray data. PMID:19939286

  3. Gene Discovery in the Apicomplexa as Revealed by EST Sequencing and Assembly of a Comparative Gene Database

    PubMed Central

    Li, Li; Brunk, Brian P.; Kissinger, Jessica C.; Pape, Deana; Tang, Keliang; Cole, Robert H.; Martin, John; Wylie, Todd; Dante, Mike; Fogarty, Steven J.; Howe, Daniel K.; Liberator, Paul; Diaz, Carmen; Anderson, Jennifer; White, Michael; Jerome, Maria E.; Johnson, Emily A.; Radke, Jay A.; Stoeckert, Christian J.; Waterston, Robert H.; Clifton, Sandra W.; Roos, David S.; Sibley, L. David

    2003-01-01

    Large-scale EST sequencing projects for several important parasites within the phylum Apicomplexa were undertaken for the purpose of gene discovery. Included were several parasites of medical importance (Plasmodium falciparum, Toxoplasma gondii) and others of veterinary importance (Eimeria tenella, Sarcocystis neurona, and Neospora caninum). A total of 55,192 ESTs, deposited into dbEST/GenBank, were included in the analyses. The resulting sequences have been clustered into nonredundant gene assemblies and deposited into a relational database that supports a variety of sequence and text searches. This database has been used to compare the gene assemblies using BLAST similarity comparisons to the public protein databases to identify putative genes. Of these new entries, ∼15%–20% represent putative homologs with a conservative cutoff of p < 10−9, thus identifying many conserved genes that are likely to share common functions with other well-studied organisms. Gene assemblies were also used to identify strain polymorphisms, examine stage-specific expression, and identify gene families. An interesting class of genes that are confined to members of this phylum and not shared by plants, animals, or fungi, was identified. These genes likely mediate the novel biological features of members of the Apicomplexa and hence offer great potential for biological investigation and as possible therapeutic targets. [The sequence data from this study have been submitted to dbEST division of GenBank under accession nos.: Toxoplasma gondii: –, –, –, –, – , –, –, –, –. Plasmodium falciparum: –, –, –, –. Sarcocystis neurona: , , , , , , , , , , , , , –, –, –, –, –. Eimeria tenella: –, –, –, –, –, –, –, –, – , –, –, –, –, –, –, –, –, –, –, –. Neospora caninum: –, –, , – , –, –.] PMID:12618375

  4. A small diffusible signal molecule is responsible for the global control of virulence and exoenzyme production in the plant pathogen Erwinia carotovora.

    PubMed Central

    Pirhonen, M; Flego, D; Heikinheimo, R; Palva, E T

    1993-01-01

    Virulence of the plant pathogen Erwinia carotovora subsp. carotovora is dependent on the production and secretion of a complex arsenal of plant cell wall-degrading enzymes. Production of these exoenzymes is controlled by a global regulatory mechanism. A virulent mutants in one of the regulatory loci, expI, show a pleiotropic defect in the growth phase-dependent transcriptional activation of exoenzyme gene expression. The expI gene encodes a 26 kDa polypeptide that is structurally and functionally related to the luxI gene product of Vibrio fischeri. Functional similarity of expI and luxI has been demonstrated by reciprocal genetic complementation experiments. LuxI controls bioluminescence in V.fischeri in a growth phase-dependent manner by directing the synthesis of the diffusible autoinducer, N-(3-oxohexanoyl) homoserine lactone. E.c. subsp. carotovora expI+ strains or Escherichia coli harboring the cloned expI gene excrete a small diffusible signal molecule that complements the expI mutation of Erwinia as well as a luxI mutation of V.fischeri. This extracellular complementation can also be achieved by E.coli harboring the luxI gene from V.fischeri or by adding the synthetic V.fischeri autoinducer. Both the production of the plant tissue-macerating exoenzymes and the ability of the bacteria to propagate in planta are restored in expI mutants by autoinducer addition. These data suggest that the same signal molecule is employed in control of such diverse processes as virulence in a plant pathogen and bioluminescence in a marine bacterium, and may represent a general mechanism by which bacteria modulate gene expression in response to changing environmental conditions. Images PMID:8508772

  5. A small diffusible signal molecule is responsible for the global control of virulence and exoenzyme production in the plant pathogen Erwinia carotovora.

    PubMed

    Pirhonen, M; Flego, D; Heikinheimo, R; Palva, E T

    1993-06-01

    Virulence of the plant pathogen Erwinia carotovora subsp. carotovora is dependent on the production and secretion of a complex arsenal of plant cell wall-degrading enzymes. Production of these exoenzymes is controlled by a global regulatory mechanism. A virulent mutants in one of the regulatory loci, expI, show a pleiotropic defect in the growth phase-dependent transcriptional activation of exoenzyme gene expression. The expI gene encodes a 26 kDa polypeptide that is structurally and functionally related to the luxI gene product of Vibrio fischeri. Functional similarity of expI and luxI has been demonstrated by reciprocal genetic complementation experiments. LuxI controls bioluminescence in V.fischeri in a growth phase-dependent manner by directing the synthesis of the diffusible autoinducer, N-(3-oxohexanoyl) homoserine lactone. E.c. subsp. carotovora expI+ strains or Escherichia coli harboring the cloned expI gene excrete a small diffusible signal molecule that complements the expI mutation of Erwinia as well as a luxI mutation of V.fischeri. This extracellular complementation can also be achieved by E.coli harboring the luxI gene from V.fischeri or by adding the synthetic V.fischeri autoinducer. Both the production of the plant tissue-macerating exoenzymes and the ability of the bacteria to propagate in planta are restored in expI mutants by autoinducer addition. These data suggest that the same signal molecule is employed in control of such diverse processes as virulence in a plant pathogen and bioluminescence in a marine bacterium, and may represent a general mechanism by which bacteria modulate gene expression in response to changing environmental conditions.

  6. Changes in dopamine and ZENK during suppression of myopia in chicks by intense illuminance.

    PubMed

    Lan, Weizhong; Yang, Zhikuan; Feldkaemper, Marita; Schaeffel, Frank

    2016-04-01

    High ambient illuminances have been found to slow the development of deprivation myopia in several animal models. Almost complete inhibition of myopia was observed in chickens when intermittent episodes of high illuminance were alternated with standard office illuminance (50% duty cycle, alternate periods of 1 min 15,000 lux and 1 min 500 lux, continued for 10 h per day), or when illuminances were increased to 40,000 lux. Since the mechanisms by which bright light suppresses myopia are poorly understood, we have studied the roles of two well-established signaling molecules in myopia, dopamine and ZENK, in the chicken. In line with previous studies, we found that retinal dopamine release (as reflected by vitreal DOPAC content) was severely reduced during development of deprivation myopia. We found that illuminance of 15,000 lux, provided by quartz-halogen lamps, partially rescued the drop in retinal dopamine release. The finding is in line with the assumption that dopamine is involved in the light-induced inhibition of myopia. No differences in vitreal DOPAC were found when bright light was provided continuously or with 1:1 min alternating exposure with 500 lux. As previously described by others, wearing diffusers suppressed the expression of ZENK protein in glucagonergic amacrine cells (GACs) but neither continuous nor 1:1 min alternating bright to normal light could rescue the suppression of ZENK in GACs. While it is well known that light increases global retinal ZENK mRNA and protein levels, the changes of ZENK protein induced specifically in GACs by diffuser wear appear independent of light levels. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Pilot study of a novel classroom designed to prevent myopia by increasing children's exposure to outdoor light.

    PubMed

    Zhou, Zhongqiang; Chen, Tingting; Wang, Mengrui; Jin, Ling; Zhao, Yongyi; Chen, Shangji; Wang, Congyao; Zhang, Guoshan; Wang, Qilin; Deng, Qiaoming; Liu, Yubo; Morgan, Ian G; He, Mingguang; Liu, Yizhi; Congdon, Nathan

    2017-01-01

    We sought to assess light characteristics and user acceptability of a prototype Bright Classroom (BC), designed to prevent children's myopia by exposing them to light conditions resembling the outdoors. Conditions were measured throughout the school year in the glass-constructed BC, a traditional classroom (TC) and outdoors. Teachers and children completed user questionnaires, and children rated reading comfort at different light intensities. A total of 230 children (mean age 10.2 years, 57.4% boys) and 13 teachers (36.8 years, 15.4% men) completed questionnaires. The median (Inter Quartile Range) light intensity in the BC (2,540 [1,330-4,060] lux) was greater than the TC (477 [245-738] lux, P < 0.001), though less than outdoors (19,500 [8,960-36,000] lux, P < 0.001). A prominent spectral peak at 490-560 nm was present in the BC and outdoors, but less so in the TC. Teachers and children gave higher overall ratings to the BC than TC, and light intensity in the BC in summer and on sunny days (>5,000 lux) was at the upper limit of children's comfort for reading. In summary, light intensity in the BC exceeds TC, and is at the practical upper limit for routine use. Children and teachers prefer the BC.

  8. Emodin affects biofilm formation and expression of virulence factors in Streptococcus suis ATCC700794.

    PubMed

    Yang, Yan-Bei; Wang, Shuai; Wang, Chang; Huang, Quan-Yong; Bai, Jing-Wen; Chen, Jian-Qing; Chen, Xue-Ying; Li, Yan-Hua

    2015-12-01

    Streptococcus suis (S. suis) is a swine pathogen and also a zoonotic agent. In this study, the effects of subinhibitory concentrations (sub-MICs) of emodin on biofilm formation by S. suis ATCC700794 were evaluated. As quantified by crystal violet staining, biofilm formation by S. suis ATCC700794 was dose-dependently decreased after growth with 1/2 MIC, 1/4 MIC, or 1/8 MIC of emodin. By scanning electron microscopy, the structural architecture of the S. suis ATCC700794 biofilms was examined following growth in culture medium supplemented with 1/2 MIC, 1/4 MIC, 1/8 MIC, or 1/16 MIC of emodin. Scanning electron microscopy analysis revealed the potential effect of emodin on biofilm formation by S. suis ATCC700794. The expression of luxS gene and virulence genes in S. suis ATCC700794 was investigated by quantitative RT-PCR. It was found that sub-MICs of emodin significantly decreased the expression of gapdh, sly, fbps, ef, and luxS. However, it was found that sub-MICs of emodin significantly increased the expression of cps2J, mrp, and gdh. These findings showed that sub-MICs of emodin could cause the difference in the expression level of the virulence genes.

  9. Light adaptation does not prevent early retinal abnormalities in diabetic rats

    PubMed Central

    Kur, Joanna; Burian, Michael A.; Newman, Eric A.

    2016-01-01

    The aetiology of diabetic retinopathy (DR), the leading cause of blindness in the developed world, remains controversial. One hypothesis holds that retinal hypoxia, exacerbated by the high O2 consumption of rod photoreceptors in the dark, is a primary cause of DR. Based on this prediction we investigated whether early retinal abnormalities in streptozotocin-induced diabetic rats are alleviated by preventing the rods from dark adapting. Diabetic rats and their non-diabetic littermates were housed in a 12:12 hour light-dim light photocycle (30 lux during the day and 3 lux at night). Progression of early retinal abnormalities in diabetic rats was assessed by monitoring the ERG b-wave and oscillatory potentials, Müller cell reactive gliosis, and neuronal cell death, as assayed by TUNEL staining and retinal thickness at 6 and 12 weeks after diabetes induction. Maintaining diabetic animals in a dim-adapting light did not slow the progression of these neuronal and glial changes when compared to diabetic rats maintained in a standard 12:12 hour light-dark photocycle (30 lux during the day and 0 lux at night). Our results indicate that neuronal and glial abnormalities in early stages of diabetes are not exacerbated by rod photoreceptor O2 consumption in the dark. PMID:26852722

  10. Development and characterization of novel EST-SSR markers and their application for genetic diversity analysis of Jerusalem artichoke (Helianthus tuberosus L.).

    PubMed

    Mornkham, T; Wangsomnuk, P P; Mo, X C; Francisco, F O; Gao, L Z; Kurzweil, H

    2016-10-24

    Jerusalem artichoke (Helianthus tuberosus L.) is a perennial tuberous plant and a traditional inulin-rich crop in Thailand. It has become the most important source of inulin and has great potential for use in chemical and food industries. In this study, expressed sequence tag (EST)-based simple sequence repeat (SSR) markers were developed from 40,362 Jerusalem artichoke ESTs retrieved from the NCBI database. Among 23,691 non-redundant identified ESTs, 1949 SSR motifs harboring 2 to 6 nucleotides with varied repeat motifs were discovered from 1676 assembled sequences. Seventy-nine primer pairs were generated from EST sequences harboring SSR motifs. Our results show that 43 primers are polymorphic for the six studied populations, while the remaining 36 were either monomorphic or failed to amplify. These 43 SSR loci exhibited a high level of genetic diversity among populations, with allele numbers varying from 2 to 7, with an average of 3.95 alleles per loci. Heterozygosity ranged from 0.096 to 0.774, with an average of 0.536; polymorphic index content ranged from 0.096 to 0.854, with an average of 0.568. Principal component analysis and neighbor-joining analysis revealed that the six populations could be divided into six clusters. Our results indicate that these newly characterized EST-SSR markers may be useful in the exploration of genetic diversity and range expansion of the Jerusalem artichoke, and in cross-species application for the genus Helianthus.

  11. tropiTree: An NGS-Based EST-SSR Resource for 24 Tropical Tree Species

    PubMed Central

    Russell, Joanne R.; Hedley, Peter E.; Cardle, Linda; Dancey, Siobhan; Morris, Jenny; Booth, Allan; Odee, David; Mwaura, Lucy; Omondi, William; Angaine, Peter; Machua, Joseph; Muchugi, Alice; Milne, Iain; Kindt, Roeland; Jamnadass, Ramni; Dawson, Ian K.

    2014-01-01

    The development of genetic tools for non-model organisms has been hampered by cost, but advances in next-generation sequencing (NGS) have created new opportunities. In ecological research, this raises the prospect for developing molecular markers to simultaneously study important genetic processes such as gene flow in multiple non-model plant species within complex natural and anthropogenic landscapes. Here, we report the use of bar-coded multiplexed paired-end Illumina NGS for the de novo development of expressed sequence tag-derived simple sequence repeat (EST-SSR) markers at low cost for a range of 24 tree species. Each chosen tree species is important in complex tropical agroforestry systems where little is currently known about many genetic processes. An average of more than 5,000 EST-SSRs was identified for each of the 24 sequenced species, whereas prior to analysis 20 of the species had fewer than 100 nucleotide sequence citations. To make results available to potential users in a suitable format, we have developed an open-access, interactive online database, tropiTree (http://bioinf.hutton.ac.uk/tropiTree), which has a range of visualisation and search facilities, and which is a model for the efficient presentation and application of NGS data. PMID:25025376

  12. Using the mouse embryonic stem cell test (EST) to evaluate the embryotoxicity of haloacetic acids

    EPA Science Inventory

    The Embryonic Stem Cell Test (EST) is used to predict the embryotoxic potential of a test compound by combining the data from cytotoxicity assays in undifferentiated mouse embryonic stem (mES) cells and differentiated mouse cells with the data from a differentiation assay in mES ...

  13. An elm EST database for identifying leaf beetle egg-induced defense genes

    PubMed Central

    2012-01-01

    Background Plants can defend themselves against herbivorous insects prior to the onset of larval feeding by responding to the eggs laid on their leaves. In the European field elm (Ulmus minor), egg laying by the elm leaf beetle ( Xanthogaleruca luteola) activates the emission of volatiles that attract specialised egg parasitoids, which in turn kill the eggs. Little is known about the transcriptional changes that insect eggs trigger in plants and how such indirect defense mechanisms are orchestrated in the context of other biological processes. Results Here we present the first large scale study of egg-induced changes in the transcriptional profile of a tree. Five cDNA libraries were generated from leaves of (i) untreated control elms, and elms treated with (ii) egg laying and feeding by elm leaf beetles, (iii) feeding, (iv) artificial transfer of egg clutches, and (v) methyl jasmonate. A total of 361,196 ESTs expressed sequence tags (ESTs) were identified which clustered into 52,823 unique transcripts (Unitrans) and were stored in a database with a public web interface. Among the analyzed Unitrans, 73% could be annotated by homology to known genes in the UniProt (Plant) database, particularly to those from Vitis, Ricinus, Populus and Arabidopsis. Comparative in silico analysis among the different treatments revealed differences in Gene Ontology term abundances. Defense- and stress-related gene transcripts were present in high abundance in leaves after herbivore egg laying, but transcripts involved in photosynthesis showed decreased abundance. Many pathogen-related genes and genes involved in phytohormone signaling were expressed, indicative of jasmonic acid biosynthesis and activation of jasmonic acid responsive genes. Cross-comparisons between different libraries based on expression profiles allowed the identification of genes with a potential relevance in egg-induced defenses, as well as other biological processes, including signal transduction, transport and

  14. An elm EST database for identifying leaf beetle egg-induced defense genes.

    PubMed

    Büchel, Kerstin; McDowell, Eric; Nelson, Will; Descour, Anne; Gershenzon, Jonathan; Hilker, Monika; Soderlund, Carol; Gang, David R; Fenning, Trevor; Meiners, Torsten

    2012-06-15

    Plants can defend themselves against herbivorous insects prior to the onset of larval feeding by responding to the eggs laid on their leaves. In the European field elm (Ulmus minor), egg laying by the elm leaf beetle ( Xanthogaleruca luteola) activates the emission of volatiles that attract specialised egg parasitoids, which in turn kill the eggs. Little is known about the transcriptional changes that insect eggs trigger in plants and how such indirect defense mechanisms are orchestrated in the context of other biological processes. Here we present the first large scale study of egg-induced changes in the transcriptional profile of a tree. Five cDNA libraries were generated from leaves of (i) untreated control elms, and elms treated with (ii) egg laying and feeding by elm leaf beetles, (iii) feeding, (iv) artificial transfer of egg clutches, and (v) methyl jasmonate. A total of 361,196 ESTs expressed sequence tags (ESTs) were identified which clustered into 52,823 unique transcripts (Unitrans) and were stored in a database with a public web interface. Among the analyzed Unitrans, 73% could be annotated by homology to known genes in the UniProt (Plant) database, particularly to those from Vitis, Ricinus, Populus and Arabidopsis. Comparative in silico analysis among the different treatments revealed differences in Gene Ontology term abundances. Defense- and stress-related gene transcripts were present in high abundance in leaves after herbivore egg laying, but transcripts involved in photosynthesis showed decreased abundance. Many pathogen-related genes and genes involved in phytohormone signaling were expressed, indicative of jasmonic acid biosynthesis and activation of jasmonic acid responsive genes. Cross-comparisons between different libraries based on expression profiles allowed the identification of genes with a potential relevance in egg-induced defenses, as well as other biological processes, including signal transduction, transport and primary metabolism

  15. Gene discovery using next-generation pyrosequencing to develop ESTs for Phalaenopsis orchids

    PubMed Central

    2011-01-01

    Background Orchids are one of the most diversified angiosperms, but few genomic resources are available for these non-model plants. In addition to the ecological significance, Phalaenopsis has been considered as an economically important floriculture industry worldwide. We aimed to use massively parallel 454 pyrosequencing for a global characterization of the Phalaenopsis transcriptome. Results To maximize sequence diversity, we pooled RNA from 10 samples of different tissues, various developmental stages, and biotic- or abiotic-stressed plants. We obtained 206,960 expressed sequence tags (ESTs) with an average read length of 228 bp. These reads were assembled into 8,233 contigs and 34,630 singletons. The unigenes were searched against the NCBI non-redundant (NR) protein database. Based on sequence similarity with known proteins, these analyses identified 22,234 different genes (E-value cutoff, e-7). Assembled sequences were annotated with Gene Ontology, Gene Family and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Among these annotations, over 780 unigenes encoding putative transcription factors were identified. Conclusion Pyrosequencing was effective in identifying a large set of unigenes from Phalaenopsis. The informative EST dataset we developed constitutes a much-needed resource for discovery of genes involved in various biological processes in Phalaenopsis and other orchid species. These transcribed sequences will narrow the gap between study of model organisms with many genomic resources and species that are important for ecological and evolutionary studies. PMID:21749684

  16. Draft Genome Sequence of Rhodobacteraceae Strain PD-2, an Algicidal Bacterium with a Quorum-Sensing System, Isolated from the Marine Microalga Prorocentrum donghaiense.

    PubMed

    Zheng, Li; Cui, Zhisong; Xu, Luyan; Sun, Chengjun; Powell, Ryan J; Hill, Russell T

    2015-02-19

    Rhodobacteraceae strain PD-2 was isolated from the marine microalga Prorocentrum donghaiense. It has algicidal activity toward its host and could produce N-acylhomoserine lactone signals. Here, we present the draft genome of strain PD-2, which contains 5,227,214 bp with an average GC content of 66.19%. There were 4,864 encoding gene sequences and two clusters of luxI and luxR homologues identified. Copyright © 2015 Zheng et al.

  17. SCARF: maximizing next-generation EST assemblies for evolutionary and population genomic analyses.

    PubMed

    Barker, Michael S; Dlugosch, Katrina M; Reddy, A Chaitanya C; Amyotte, Sarah N; Rieseberg, Loren H

    2009-02-15

    Scaffolded and Corrected Assembly of Roche 454 (SCARF) is a next-generation sequence assembly tool for evolutionary genomics that is designed especially for assembling 454 EST sequences against high-quality reference sequences from related species. The program was created to knit together 454 contigs that do not assemble during traditional de novo assembly, using a reference sequence library to orient the 454 sequences. SCARF is freely available at http://msbarker.com/software.htm, and is released under the open source GPLv3 license (http://www.opensource.org/licenses/gpl-3.0.html.

  18. Est16, a New Esterase Isolated from a Metagenomic Library of a Microbial Consortium Specializing in Diesel Oil Degradation.

    PubMed

    Pereira, Mariana Rangel; Mercaldi, Gustavo Fernando; Maester, Thaís Carvalho; Balan, Andrea; Lemos, Eliana Gertrudes de Macedo

    2015-01-01

    Lipolytic enzymes have attracted attention from a global market because they show enormous biotechnological potential for applications such as detergent production, leather processing, cosmetics production, and use in perfumes and biodiesel. Due to the intense demand for biocatalysts, a metagenomic approach provides methods of identifying new enzymes. In this study, an esterase designated as Est16 was selected from 4224 clones of a fosmid metagenomic library, revealing an 87% amino acid identity with an esterase/lipase (accession number ADM63076.1) from an uncultured bacterium. Phylogenetic studies showed that the enzyme belongs to family V of bacterial lipolytic enzymes and has sequence and structural similarities with an aryl-esterase from Pseudomonas fluorescens and a patented Anti-Kazlauskas lipase (patent number US20050153404). The protein was expressed and purified as a highly soluble, thermally stable enzyme that showed a preference for basic pH. Est16 exhibited activity toward a wide range of substrates and the highest catalytic efficiency against p-nitrophenyl butyrate and p-nitrophenyl valerate. Est16 also showed tolerance to the presence of organic solvents, detergents and metals. Based on molecular modeling, we showed that the large alpha-beta domain is conserved in the patented enzymes but not the substrate pocket. Here, it was demonstrated that a metagenomic approach is suitable for discovering the lipolytic enzyme diversity and that Est16 has the biotechnological potential for use in industrial processes.

  19. Analysis and functional annotation of expressed sequence tags (ESTs) from multiple tissues of oil palm (Elaeis guineensis Jacq.)

    PubMed Central

    Ho, Chai-Ling; Kwan, Yen-Yen; Choi, Mei-Chooi; Tee, Sue-Sean; Ng, Wai-Har; Lim, Kok-Ang; Lee, Yang-Ping; Ooi, Siew-Eng; Lee, Weng-Wah; Tee, Jin-Ming; Tan, Siang-Hee; Kulaveerasingam, Harikrishna; Alwee, Sharifah Shahrul Rabiah Syed; Abdullah, Meilina Ong

    2007-01-01

    Background Oil palm is the second largest source of edible oil which contributes to approximately 20% of the world's production of oils and fats. In order to understand the molecular biology involved in in vitro propagation, flowering, efficient utilization of nitrogen sources and root diseases, we have initiated an expressed sequence tag (EST) analysis on oil palm. Results In this study, six cDNA libraries from oil palm zygotic embryos, suspension cells, shoot apical meristems, young flowers, mature flowers and roots, were constructed. We have generated a total of 14537 expressed sequence tags (ESTs) from these libraries, from which 6464 tentative unique contigs (TUCs) and 2129 singletons were obtained. Approximately 6008 of these tentative unique genes (TUGs) have significant matches to the non-redundant protein database, from which 2361 were assigned to one or more Gene Ontology categories. Predominant transcripts and differentially expressed genes were identified in multiple oil palm tissues. Homologues of genes involved in many aspects of flower development were also identified among the EST collection, such as CONSTANS-like, AGAMOUS-like (AGL)2, AGL20, LFY-like, SQUAMOSA, SQUAMOSA binding protein (SBP) etc. Majority of them are the first representatives in oil palm, providing opportunities to explore the cause of epigenetic homeotic flowering abnormality in oil palm, given the importance of flowering in fruit production. The transcript levels of two flowering-related genes, EgSBP and EgSEP were analysed in the flower tissues of various developmental stages. Gene homologues for enzymes involved in oil biosynthesis, utilization of nitrogen sources, and scavenging of oxygen radicals, were also uncovered among the oil palm ESTs. Conclusion The EST sequences generated will allow comparative genomic studies between oil palm and other monocotyledonous and dicotyledonous plants, development of gene-targeted markers for the reference genetic map, design and

  20. Construction and EST sequencing of full-length, drought stress cDNA libraries for common beans (Phaseolus vulgaris L.)

    PubMed Central

    2011-01-01

    Background Common bean is an important legume crop with only a moderate number of short expressed sequence tags (ESTs) made with traditional methods. The goal of this research was to use full-length cDNA technology to develop ESTs that would overlap with the beginning of open reading frames and therefore be useful for gene annotation of genomic sequences. The library was also constructed to represent genes expressed under drought, low soil phosphorus and high soil aluminum toxicity. We also undertook comparisons of the full-length cDNA library to two previous non-full clone EST sets for common bean. Results Two full-length cDNA libraries were constructed: one for the drought tolerant Mesoamerican genotype BAT477 and the other one for the acid-soil tolerant Andean genotype G19833 which has been selected for genome sequencing. Plants were grown in three soil types using deep rooting cylinders subjected to drought and non-drought stress and tissues were collected from both roots and above ground parts. A total of 20,000 clones were selected robotically, half from each library. Then, nearly 10,000 clones from the G19833 library were sequenced with an average read length of 850 nucleotides. A total of 4,219 unigenes were identified consisting of 2,981 contigs and 1,238 singletons. These were functionally annotated with gene ontology terms and placed into KEGG pathways. Compared to other EST sequencing efforts in common bean, about half of the sequences were novel or represented the 5' ends of known genes. Conclusions The present full-length cDNA libraries add to the technological toolbox available for common bean and our sequencing of these clones substantially increases the number of unique EST sequences available for the common bean genome. All of this should be useful for both functional gene annotation, analysis of splice site variants and intron/exon boundary determination by comparison to soybean genes or with common bean whole-genome sequences. In addition the

  1. EST-derived SSR markers used as anchor loci for the construction of a consensus linkage map in ryegrass (Lolium spp.)

    PubMed Central

    2010-01-01

    Background Genetic markers and linkage mapping are basic prerequisites for marker-assisted selection and map-based cloning. In the case of the key grassland species Lolium spp., numerous mapping populations have been developed and characterised for various traits. Although some genetic linkage maps of these populations have been aligned with each other using publicly available DNA markers, the number of common markers among genetic maps is still low, limiting the ability to compare candidate gene and QTL locations across germplasm. Results A set of 204 expressed sequence tag (EST)-derived simple sequence repeat (SSR) markers has been assigned to map positions using eight different ryegrass mapping populations. Marker properties of a subset of 64 EST-SSRs were assessed in six to eight individuals of each mapping population and revealed 83% of the markers to be polymorphic in at least one population and an average number of alleles of 4.88. EST-SSR markers polymorphic in multiple populations served as anchor markers and allowed the construction of the first comprehensive consensus map for ryegrass. The integrated map was complemented with 97 SSRs from previously published linkage maps and finally contained 284 EST-derived and genomic SSR markers. The total map length was 742 centiMorgan (cM), ranging for individual chromosomes from 70 cM of linkage group (LG) 6 to 171 cM of LG 2. Conclusions The consensus linkage map for ryegrass based on eight mapping populations and constructed using a large set of publicly available Lolium EST-SSRs mapped for the first time together with previously mapped SSR markers will allow for consolidating existing mapping and QTL information in ryegrass. Map and markers presented here will prove to be an asset in the development for both molecular breeding of ryegrass as well as comparative genetics and genomics within grass species. PMID:20712870

  2. Qu’est-ce que l’hidradénite suppurée?

    PubMed Central

    Lee, Erika Yue; Alhusayen, Raed; Lansang, Perla; Shear, Neil; Yeung, Jensen

    2017-01-01

    Résumé Objectif Permettre aux médecins de famille de comprendre l’épidémiologie, le tableau clinique, le diagnostic et la prise en charge de l’hidradénite suppurée. Sources d’information Une recherche de la littérature a été effectuée sur PubMed à l’aide des mots-clés MeSH hidradenitis suppurativa. Message principal L’hidradénite suppurée est une affection cutanée chronique, récidivante et incapacitante. C’est un trouble inflammatoire de l’épithélium folliculaire, bien qu’une infection bactérienne secondaire se produise souvent. Le diagnostic, posé en clinique, repose sur les lésions typiques (nodules, abcès, tractus sinusal), le siège (plis cutanés), la nature des rechutes et le caractère chronique. De nombreuses comorbidités sont associées à l’hidradénite suppurée, y compris l’obésité, le syndrome métabolique, la maladie intestinale inflammatoire et la spondylarthropathie. Même si l’absence de traitement curatif et la nature récidivante de l’hidradénite suppurée en compliquent le traitement, il existe des options efficaces pour prendre en charge les symptômes. Conclusion Les médecins de famille doivent soupçonner l’hidradénite suppurée chez les patients qui présentent des abcès cutanés récidivants dans les plis cutanés. Les médecins de famille jouent un rôle important dans le diagnostic précoce, l’instauration du traitement et la recommandation en dermatologie avant que l’hidradénite suppurée ne progresse vers une atteinte terminale incapacitante. PMID:28209697

  3. Evaluation of the effects of sdiA, a luxR homologue, on adherence and motility of Escherichia coli O157 : H7.

    PubMed

    Sharma, Vijay K; Bearson, Shawn M D; Bearson, Bradley L

    2010-05-01

    Quorum-sensing (QS) signalling pathways are important regulatory networks for controlling the expression of genes promoting adherence of enterohaemorrhagic Escherichia coli (EHEC) O157 : H7 to epithelial cells. A recent study has shown that EHEC O157 : H7 encodes a luxR homologue, called sdiA, which upon overexpression reduces the expression of genes encoding flagellar and locus of enterocyte effacement (LEE) proteins, thus negatively impacting on the motility and intimate adherence phenotypes, respectively. Here, we show that the deletion of sdiA from EHEC O157 : H7 strain 86-24, and from a hha (a negative regulator of ler) mutant of this strain, enhanced bacterial adherence to HEp-2 epithelial cells of the sdiA mutant strains relative to the strains containing a wild-type copy of sdiA. Quantitative reverse transcription PCR showed that the expression of LEE-encoded genes ler, espA and eae in strains with the sdiA deletions was not significantly different from that of the strains wild-type for sdiA. Similarly, no additional increases in the expression of LEE genes were observed in a sdiA hha double mutant strain relative to that observed in the hha deletion mutant. While the expression of fliC, which encodes flagellin, was enhanced in the sdiA mutant strain, the expression of fliC was reduced by several fold in the hha mutant strain, irrespective of the presence or absence of sdiA, indicating that the genes sdiA and hha exert opposing effects on the expression of fliC. The strains with deletions in sdiA or hha showed enhanced expression of csgA, encoding curlin of the curli fimbriae, with the expression of csgA highest in the sdiA hha double mutant, suggesting an additive effect of these two gene deletions on the expression of csgA. No significant differences were observed in the expression of the genes lpfA and fimA of the operons encoding long polar and type 1 fimbriae in the sdiA mutant strain. These data indicate that SdiA has no significant effect on the

  4. Effects of Early Bright, Late Bright and Dim Illumination upon Circadian Neuroendocrine, Electrophysiological and Behavioral Responses

    DTIC Science & Technology

    1992-07-29

    ranging from about 50 lux for computer monitor display work to approximately 3500 lux for such tasks as reading # 4 pencil handwriting and machine repair...regulation of physiology, mood and behavior. In: Bggic Effects of Light (Holick & Kligman, Eds.) New York: Walter de Gruyter & Co. (in press) Gaddy...1991 meetings. i~ge,~c 8! pFP EZ-T9 C0 F OGHr BIOLOGICAL EFFECTS OF LIGHT IN HUMANS: THE REGULATION OF PHYSIOLOGY, MOOD AND BEHAVIOR George C

  5. Development of highly polymorphic EST-SSR markers and segregation in F₁ hybrid population of Vitis vinifera L.

    PubMed

    Kayesh, E; Zhang, Y Y; Liu, G S; Bilkish, N; Sun, X; Leng, X P; Fang, J G

    2013-09-23

    The objectives of this investigation were to develop and validate the expressed sequence tag (EST)-simple sequence repeat (SSR) markers from large EST sequences, and to study the segregation and distribution of SSRs within two grapevine parental lines. In total, 94 F₁ lines crossed between "Early Rose" and "Red Globe" were studied. Approximately 2100 EST-SSR sequences of Vitis vinifera L. were searched for SSRs and analyzed for the design of polymerase chain reaction (PCR) primers amplifying the SSR-rich regions. Trinucleotide repeats were found to be the most abundant, followed by other nucleotide repeats. A total of 182 SSR primer pairs were first developed for the study on the parental polymorphism. Among the 182 SSR primers, 142 primer pairs (78%) could amplify the anticipated PCR products, among which only 52 primer pairs (36.62%) showed polymorphism between the two parents. These polymorphic bands were further surveyed among the 94 F₁ lines, and the results showed that a total of 162 bands were amplified, and 98 of them were polymorphic in both parents (60.86% polymorphism), with an average of 1.88 polymorphic DNA bands for each primer pair. After testing with the chi-square test, 33 of the clearly amplified polymorphic bands followed a 3:1 ratio, and 37 followed a 1:1 ratio. The rest showed distorted segregation ratios.

  6. What Do Animal Studies Tell Us about the Mechanism of Myopia-Protection by Light?

    PubMed

    Norton, Thomas T

    2016-09-01

    : Human studies have provided strong evidence that exposure to time outdoors is protective against the onset of myopia. A causal factor may be that the light levels outdoors (30,000-130,000 lux) are much higher than light levels indoors (typically less than 500 lux). Studies using animal models have found that normal animals exposed to low illuminance levels (50 lux) can develop myopia. The myopia and axial elongation, produced in animals by monocular form deprivation, is reduced by light levels in the 15,000 to 25,000 range. Myopia induced with a negative-power lens seems less affected, perhaps because the lens provides a powerful target for the emmetropization mechanism. Animal studies suggest that raising the light levels may have their effect by increasing retinal dopamine activity, probably via the D2 receptor pathway, altering gene expression in the retina and reducing the signals that produce axial elongation.

  7. Light sensors for objective light measurement in ambulatory polysomnography.

    PubMed

    Schembri, Rachel; Spong, Jo; Peters, Allison; Rochford, Peter; Wilksch, Philip; O'Donoghue, Fergal J; Greenwood, Kenneth M; Barnes, Maree; Kennedy, Gerard A; Berlowitz, David J

    2017-01-01

    Ambulatory polysomnography (PSG) does not commonly include an objective measure of light to determine the time of lights off (Loff), and thus cannot be used to calculate important indices such as sleep onset latency and sleep efficiency. This study examined the technical specifications and appropriateness of a prototype light sensor (LS) for use in ambulatory Compumedics Somte PSG.Two studies were conducted. The first examined the light measurement characteristics of the LS when used with a portable PSG device, specifically recording trace range, linearity, sensitivity, and stability. This involved the LS being exposed to varying incandescent and fluorescent light levels in a light controlled room. Secondly, the LS was trialled in 24 home and 12 hospital ambulatory PSGs to investigate whether light levels in home and hospital settings were within the recording range of the LS, and to quantify the typical light intensity reduction at the time of Loff. A preliminary exploration of clinical utility was also conducted. Linearity between LS voltage and lux was demonstrated, and the LS trace was stable over 14 hours of recording. The observed maximum voltage output of the LS/PSG device was 250 mV, corresponding to a maximum recording range of 350 lux and 523 lux for incandescent and fluorescent light respectively. At the time of Loff, light levels were within the recording range of the LS, and on average dropped by 72 lux (9-245) in the home and 76 lux (4-348) in the hospital setting. Results suggest that clinical utility was greatest in hospital settings where patients are less mobile. The LS was a simple and effective objective marker of light level in portable PSG, which can be used to identify Loff in ambulatory PSG. This allows measurement of additional sleep indices and support with clinical decisions.

  8. Analysis of expressed sequence tags from Actinidia: applications of a cross species EST database for gene discovery in the areas of flavor, health, color and ripening

    PubMed Central

    Crowhurst, Ross N; Gleave, Andrew P; MacRae, Elspeth A; Ampomah-Dwamena, Charles; Atkinson, Ross G; Beuning, Lesley L; Bulley, Sean M; Chagne, David; Marsh, Ken B; Matich, Adam J; Montefiori, Mirco; Newcomb, Richard D; Schaffer, Robert J; Usadel, Björn; Allan, Andrew C; Boldingh, Helen L; Bowen, Judith H; Davy, Marcus W; Eckloff, Rheinhart; Ferguson, A Ross; Fraser, Lena G; Gera, Emma; Hellens, Roger P; Janssen, Bart J; Klages, Karin; Lo, Kim R; MacDiarmid, Robin M; Nain, Bhawana; McNeilage, Mark A; Rassam, Maysoon; Richardson, Annette C; Rikkerink, Erik HA; Ross, Gavin S; Schröder, Roswitha; Snowden, Kimberley C; Souleyre, Edwige JF; Templeton, Matt D; Walton, Eric F; Wang, Daisy; Wang, Mindy Y; Wang, Yanming Y; Wood, Marion; Wu, Rongmei; Yauk, Yar-Khing; Laing, William A

    2008-01-01

    Background Kiwifruit (Actinidia spp.) are a relatively new, but economically important crop grown in many different parts of the world. Commercial success is driven by the development of new cultivars with novel consumer traits including flavor, appearance, healthful components and convenience. To increase our understanding of the genetic diversity and gene-based control of these key traits in Actinidia, we have produced a collection of 132,577 expressed sequence tags (ESTs). Results The ESTs were derived mainly from four Actinidia species (A. chinensis, A. deliciosa, A. arguta and A. eriantha) and fell into 41,858 non redundant clusters (18,070 tentative consensus sequences and 23,788 EST singletons). Analysis of flavor and fragrance-related gene families (acyltransferases and carboxylesterases) and pathways (terpenoid biosynthesis) is presented in comparison with a chemical analysis of the compounds present in Actinidia including esters, acids, alcohols and terpenes. ESTs are identified for most genes in color pathways controlling chlorophyll degradation and carotenoid biosynthesis. In the health area, data are presented on the ESTs involved in ascorbic acid and quinic acid biosynthesis showing not only that genes for many of the steps in these pathways are represented in the database, but that genes encoding some critical steps are absent. In the convenience area, genes related to different stages of fruit softening are identified. Conclusion This large EST resource will allow researchers to undertake the tremendous challenge of understanding the molecular basis of genetic diversity in the Actinidia genus as well as provide an EST resource for comparative fruit genomics. The various bioinformatics analyses we have undertaken demonstrates the extent of coverage of ESTs for genes encoding different biochemical pathways in Actinidia. PMID:18655731

  9. Expressed sequence tag (EST) analysis of two subspecies of Metarhizium anisopliae reveals a plethora of secreted proteins with potential activity in insect hosts.

    PubMed

    Freimoser, Florian M; Screen, Steven; Bagga, Savita; Hu, Gang; St Leger, Raymond J

    2003-01-01

    Expressed sequence tag (EST) libraries for Metarhizium anisopliae, the causative agent of green muscardine disease, were developed from the broad host-range pathogen Metarhizium anisopliae sf. anisopliae and the specific grasshopper pathogen, M. anisopliae sf. acridum. Approximately 1,700 5' end sequences from each subspecies were generated from cDNA libraries representing fungi grown under conditions that maximize secretion of cuticle-degrading enzymes. Both subspecies had ESTs for virtually all pathogenicity-related genes cloned to date from M. anisopliae, but many novel genes encoding potential virulence factors were also tagged. Enzymes with potential targets in the insect host included proteases, chitinases, phospholipases, lipases, esterases, phosphatases and enzymes producing toxic secondary metabolites. A diverse array of proteases composed 36 % of all M. anisopliae sf. anisopliae ESTs. Eighty percent of the ESTs that could be clustered into functional groups had significant matches (E<10(-5)) in other ascomycete fungi. These included genes reported to have specific roles in pathogens with plant or vertebrate hosts. Many of the remaining ESTs had their best BLAST match among animal, plant and bacterial sequences. These include genes with plant and microbial counterparts that produce potent antimicrobials. The abundance of transcripts discovered for different functional groups varied between the two subspecies of M. anisopliae in a manner consistent with ecological adaptations of the two pathogens. By hastening gene discovery this project has enhanced development of improved mycoinsecticides. In addition, the M. anisopliae ESTs represent a significant contribution to the extensive database of sequences from ascomycetes that are saprophytes or plant and vertebrate pathogens. Comparative analyses of these sequences is providing important information about the biology and evolutionary history of this clade.

  10. Pilot study of a novel classroom designed to prevent myopia by increasing children’s exposure to outdoor light

    PubMed Central

    Wang, Mengrui; Jin, Ling; Zhao, Yongyi; Chen, Shangji; Wang, Congyao; Zhang, Guoshan; Wang, Qilin; Deng, Qiaoming; Liu, Yubo; Morgan, Ian G.; He, Mingguang; Liu, Yizhi

    2017-01-01

    We sought to assess light characteristics and user acceptability of a prototype Bright Classroom (BC), designed to prevent children’s myopia by exposing them to light conditions resembling the outdoors. Conditions were measured throughout the school year in the glass-constructed BC, a traditional classroom (TC) and outdoors. Teachers and children completed user questionnaires, and children rated reading comfort at different light intensities. A total of 230 children (mean age 10.2 years, 57.4% boys) and 13 teachers (36.8 years, 15.4% men) completed questionnaires. The median (Inter Quartile Range) light intensity in the BC (2,540 [1,330–4,060] lux) was greater than the TC (477 [245–738] lux, P < 0.001), though less than outdoors (19,500 [8,960–36,000] lux, P < 0.001). A prominent spectral peak at 490–560 nm was present in the BC and outdoors, but less so in the TC. Teachers and children gave higher overall ratings to the BC than TC, and light intensity in the BC in summer and on sunny days (>5,000 lux) was at the upper limit of children’s comfort for reading. In summary, light intensity in the BC exceeds TC, and is at the practical upper limit for routine use. Children and teachers prefer the BC. PMID:28759614

  11. Bright lights, big city: influences of ecological light pollution on reciprocal stream-riparian invertebrate fluxes.

    PubMed

    Meyer, Lars A; Sullivan, S Mazeika P

    2013-09-01

    Cities produce considerable ecological light pollution (ELP), yet the effects of artificial night lighting on biological communities and ecosystem function have not been fully explored. From June 2010 to June 2011, we surveyed aquatic emergent insects, riparian arthropods entering the water, and riparian spiders of the family Tetragnathidae at nine stream reaches representing common ambient ELP levels of Columbus, Ohio, USA, streams (low, 0.1-0.5 lux; moderate, 0.6-2.0 lux; high, 2.1-4.0 lux). In August 2011, we experimentally increased light levels at the low- and moderate-treatment reaches to 10-12 lux to represent urban streams exposed to extremely high levels of ELP. Although season exerted the dominant influence on invertebrate fluxes over the course of the year, when analyzed by season, we found that light strongly influenced multiple invertebrate responses. The experimental light addition resulted in a 44% decrease in tetragnathid spider density (P = 0.035), decreases of 16% in family richness (P = 0.040) and 76% in mean body size (P = 0.022) of aquatic emergent insects, and a 309% increase in mean body size of terrestrial arthropods (P = 0.015). Our results provide evidence that artificial light sources can alter community structure and ecosystem function in streams via changes in reciprocal aquatic-terrestrial fluxes of invertebrates.

  12. A first step in understanding an invasive weed through its genes: an EST analysis of invasive Centaurea maculosa

    PubMed Central

    Broz, Amanda K; Broeckling, Corey D; He, Ji; Dai, Xinbin; Zhao, Patrick X; Vivanco, Jorge M

    2007-01-01

    Background The economic and biological implications of plant invasion are overwhelming; however, the processes by which plants become successful invaders are not well understood. Limited genetic resources are available for most invasive and weedy species, making it difficult to study molecular and genetic aspects that may be associated with invasion. Results As an initial step towards understanding the molecular mechanisms by which plants become invasive, we have generated a normalized Expressed Sequence Tag (EST) library comprising seven invasive populations of Centaurea maculosa, an invasive aster in North America. Seventy-seven percent of the 4423 unique transcripts showed significant similarity to existing proteins in the NCBI database and could be grouped based on gene ontology assignments. Conclusion The C. maculosa EST library represents an initial step towards looking at gene-specific expression in this species, and will pave the way for creation of other resources such as microarray chips that can help provide a view of global gene expression in invasive C. maculosa and its native counterparts. To our knowledge, this is the first published set of ESTs derived from an invasive weed that will be targeted to study invasive behavior. Understanding the genetic basis of evolution for increased invasiveness in exotic plants is critical to understanding the mechanisms through which exotic invasions occur. PMID:17524143

  13. A first step in understanding an invasive weed through its genes: an EST analysis of invasive Centaurea maculosa.

    PubMed

    Broz, Amanda K; Broeckling, Corey D; He, Ji; Dai, Xinbin; Zhao, Patrick X; Vivanco, Jorge M

    2007-05-24

    The economic and biological implications of plant invasion are overwhelming; however, the processes by which plants become successful invaders are not well understood. Limited genetic resources are available for most invasive and weedy species, making it difficult to study molecular and genetic aspects that may be associated with invasion. As an initial step towards understanding the molecular mechanisms by which plants become invasive, we have generated a normalized Expressed Sequence Tag (EST) library comprising seven invasive populations of Centaurea maculosa, an invasive aster in North America. Seventy-seven percent of the 4423 unique transcripts showed significant similarity to existing proteins in the NCBI database and could be grouped based on gene ontology assignments. The C. maculosa EST library represents an initial step towards looking at gene-specific expression in this species, and will pave the way for creation of other resources such as microarray chips that can help provide a view of global gene expression in invasive C. maculosa and its native counterparts. To our knowledge, this is the first published set of ESTs derived from an invasive weed that will be targeted to study invasive behavior. Understanding the genetic basis of evolution for increased invasiveness in exotic plants is critical to understanding the mechanisms through which exotic invasions occur.

  14. Experimental and statistical post-validation of positive example EST sequences carrying peroxisome targeting signals type 1 (PTS1).

    PubMed

    Lingner, Thomas; Kataya, Amr R A; Reumann, Sigrun

    2012-02-01

    We recently developed the first algorithms specifically for plants to predict proteins carrying peroxisome targeting signals type 1 (PTS1) from genome sequences. As validated experimentally, the prediction methods are able to correctly predict unknown peroxisomal Arabidopsis proteins and to infer novel PTS1 tripeptides. The high prediction performance is primarily determined by the large number and sequence diversity of the underlying positive example sequences, which mainly derived from EST databases. However, a few constructs remained cytosolic in experimental validation studies, indicating sequencing errors in some ESTs. To identify erroneous sequences, we validated subcellular targeting of additional positive example sequences in the present study. Moreover, we analyzed the distribution of prediction scores separately for each orthologous group of PTS1 proteins, which generally resembled normal distributions with group-specific mean values. The cytosolic sequences commonly represented outliers of low prediction scores and were located at the very tail of a fitted normal distribution. Three statistical methods for identifying outliers were compared in terms of sensitivity and specificity." Their combined application allows elimination of erroneous ESTs from positive example data sets. This new post-validation method will further improve the prediction accuracy of both PTS1 and PTS2 protein prediction models for plants, fungi, and mammals.

  15. Experimental and statistical post-validation of positive example EST sequences carrying peroxisome targeting signals type 1 (PTS1)

    PubMed Central

    Lingner, Thomas; Kataya, Amr R. A.; Reumann, Sigrun

    2012-01-01

    We recently developed the first algorithms specifically for plants to predict proteins carrying peroxisome targeting signals type 1 (PTS1) from genome sequences.1 As validated experimentally, the prediction methods are able to correctly predict unknown peroxisomal Arabidopsis proteins and to infer novel PTS1 tripeptides. The high prediction performance is primarily determined by the large number and sequence diversity of the underlying positive example sequences, which mainly derived from EST databases. However, a few constructs remained cytosolic in experimental validation studies, indicating sequencing errors in some ESTs. To identify erroneous sequences, we validated subcellular targeting of additional positive example sequences in the present study. Moreover, we analyzed the distribution of prediction scores separately for each orthologous group of PTS1 proteins, which generally resembled normal distributions with group-specific mean values. The cytosolic sequences commonly represented outliers of low prediction scores and were located at the very tail of a fitted normal distribution. Three statistical methods for identifying outliers were compared in terms of sensitivity and specificity.” Their combined application allows elimination of erroneous ESTs from positive example data sets. This new post-validation method will further improve the prediction accuracy of both PTS1 and PTS2 protein prediction models for plants, fungi, and mammals. PMID:22415050

  16. A comprehensive resource of drought- and salinity- responsive ESTs for gene discovery and marker development in chickpea (Cicer arietinum L.)

    PubMed Central

    2009-01-01

    Background Chickpea (Cicer arietinum L.), an important grain legume crop of the world is seriously challenged by terminal drought and salinity stresses. However, very limited number of molecular markers and candidate genes are available for undertaking molecular breeding in chickpea to tackle these stresses. This study reports generation and analysis of comprehensive resource of drought- and salinity-responsive expressed sequence tags (ESTs) and gene-based markers. Results A total of 20,162 (18,435 high quality) drought- and salinity- responsive ESTs were generated from ten different root tissue cDNA libraries of chickpea. Sequence editing, clustering and assembly analysis resulted in 6,404 unigenes (1,590 contigs and 4,814 singletons). Functional annotation of unigenes based on BLASTX analysis showed that 46.3% (2,965) had significant similarity (≤1E-05) to sequences in the non-redundant UniProt database. BLASTN analysis of unique sequences with ESTs of four legume species (Medicago, Lotus, soybean and groundnut) and three model plant species (rice, Arabidopsis and poplar) provided insights on conserved genes across legumes as well as novel transcripts for chickpea. Of 2,965 (46.3%) significant unigenes, only 2,071 (32.3%) unigenes could be functionally categorised according to Gene Ontology (GO) descriptions. A total of 2,029 sequences containing 3,728 simple sequence repeats (SSRs) were identified and 177 new EST-SSR markers were developed. Experimental validation of a set of 77 SSR markers on 24 genotypes revealed 230 alleles with an average of 4.6 alleles per marker and average polymorphism information content (PIC) value of 0.43. Besides SSR markers, 21,405 high confidence single nucleotide polymorphisms (SNPs) in 742 contigs (with ≥ 5 ESTs) were also identified. Recognition sites for restriction enzymes were identified for 7,884 SNPs in 240 contigs. Hierarchical clustering of 105 selected contigs provided clues about stress- responsive candidate genes

  17. The Alveolate Perkinsus marinus: Biological Insights from EST Gene Discovery

    PubMed Central

    2010-01-01

    Background Perkinsus marinus, a protozoan parasite of the eastern oyster Crassostrea virginica, has devastated natural and farmed oyster populations along the Atlantic and Gulf coasts of the United States. It is classified as a member of the Perkinsozoa, a recently established phylum considered close to the ancestor of ciliates, dinoflagellates, and apicomplexans, and a key taxon for understanding unique adaptations (e.g. parasitism) within the Alveolata. Despite intense parasite pressure, no disease-resistant oysters have been identified and no effective therapies have been developed to date. Results To gain insight into the biological basis of the parasite's virulence and pathogenesis mechanisms, and to identify genes encoding potential targets for intervention, we generated >31,000 5' expressed sequence tags (ESTs) derived from four trophozoite libraries generated from two P. marinus strains. Trimming and clustering of the sequence tags yielded 7,863 unique sequences, some of which carry a spliced leader. Similarity searches revealed that 55% of these had hits in protein sequence databases, of which 1,729 had their best hit with proteins from the chromalveolates (E-value ≤ 1e-5). Some sequences are similar to those proven to be targets for effective intervention in other protozoan parasites, and include not only proteases, antioxidant enzymes, and heat shock proteins, but also those associated with relict plastids, such as acetyl-CoA carboxylase and methyl erythrithol phosphate pathway components, and those involved in glycan assembly, protein folding/secretion, and parasite-host interactions. Conclusions Our transcriptome analysis of P. marinus, the first for any member of the Perkinsozoa, contributes new insight into its biology and taxonomic position. It provides a very informative, albeit preliminary, glimpse into the expression of genes encoding functionally relevant proteins as potential targets for chemotherapy, and evidence for the presence of a relict

  18. Genetic Diversity in Lens Species Revealed by EST and Genomic Simple Sequence Repeat Analysis

    PubMed Central

    Dikshit, Harsh Kumar; Singh, Akanksha; Singh, Dharmendra; Aski, Muraleedhar Sidaram; Prakash, Prapti; Jain, Neelu; Meena, Suresh; Kumar, Shiv; Sarker, Ashutosh

    2015-01-01

    Low productivity of pilosae type lentils grown in South Asia is attributed to narrow genetic base of the released cultivars which results in susceptibility to biotic and abiotic stresses. For enhancement of productivity and production, broadening of genetic base is essentially required. The genetic base of released cultivars can be broadened by using diverse types including bold seeded and early maturing lentils from Mediterranean region and related wild species. Genetic diversity in eighty six accessions of three species of genus Lens was assessed based on twelve genomic and thirty one EST-SSR markers. The evaluated set of genotypes included diverse lentil varieties and advanced breeding lines from Indian programme, two early maturing ICARDA lines and five related wild subspecies/species endemic to the Mediterranean region. Genomic SSRs exhibited higher polymorphism in comparison to EST SSRs. GLLC 598 produced 5 alleles with highest gene diversity value of 0.80. Among the studied subspecies/species 43 SSRs detected maximum number of alleles in L. orientalis. Based on Nei’s genetic distance cultivated lentil L. culinaris subsp. culinaris was found to be close to its wild progenitor L. culinaris subsp. orientalis. The Prichard’s structure of 86 genotypes distinguished different subspecies/species. Higher variability was recorded among individuals within population than among populations. PMID:26381889

  19. Identification of tissue-specific, abiotic stress-responsive gene expression patterns in wine grape (Vitis vinifera L.) based on curation and mining of large-scale EST data sets

    PubMed Central

    2011-01-01

    Background Abiotic stresses, such as water deficit and soil salinity, result in changes in physiology, nutrient use, and vegetative growth in vines, and ultimately, yield and flavor in berries of wine grape, Vitis vinifera L. Large-scale expressed sequence tags (ESTs) were generated, curated, and analyzed to identify major genetic determinants responsible for stress-adaptive responses. Although roots serve as the first site of perception and/or injury for many types of abiotic stress, EST sequencing in root tissues of wine grape exposed to abiotic stresses has been extremely limited to date. To overcome this limitation, large-scale EST sequencing was conducted from root tissues exposed to multiple abiotic stresses. Results A total of 62,236 expressed sequence tags (ESTs) were generated from leaf, berry, and root tissues from vines subjected to abiotic stresses and compared with 32,286 ESTs sequenced from 20 public cDNA libraries. Curation to correct annotation errors, clustering and assembly of the berry and leaf ESTs with currently available V. vinifera full-length transcripts and ESTs yielded a total of 13,278 unique sequences, with 2302 singletons and 10,976 mapped to V. vinifera gene models. Of these, 739 transcripts were found to have significant differential expression in stressed leaves and berries including 250 genes not described previously as being abiotic stress responsive. In a second analysis of 16,452 ESTs from a normalized root cDNA library derived from roots exposed to multiple, short-term, abiotic stresses, 135 genes with root-enriched expression patterns were identified on the basis of their relative EST abundance in roots relative to other tissues. Conclusions The large-scale analysis of relative EST frequency counts among a diverse collection of 23 different cDNA libraries from leaf, berry, and root tissues of wine grape exposed to a variety of abiotic stress conditions revealed distinct, tissue-specific expression patterns, previously

  20. Characterization of the Kenaf (Hibiscus cannabinus) Global Transcriptome Using Illumina Paired-End Sequencing and Development of EST-SSR Markers

    PubMed Central

    Li, Hui; Li, Defang; Chen, Anguo; Tang, Huijuan; Li, Jianjun; Huang, Siqi

    2016-01-01

    Kenaf (Hibiscus cannabinus L.) is an economically important natural fiber crop grown worldwide. However, only 20 expressed tag sequences (ESTs) for kenaf are available in public databases. The aim of this study was to develop large-scale simple sequence repeat (SSR) markers to lay a solid foundation for the construction of genetic linkage maps and marker-assisted breeding in kenaf. We used Illumina paired-end sequencing technology to generate new EST-simple sequences and MISA software to mine SSR markers. We identified 71,318 unigenes with an average length of 1143 nt and annotated these unigenes using four different protein databases. Overall, 9324 complementary pairs were designated as EST-SSR markers, and their quality was validated using 100 randomly selected SSR markers. In total, 72 primer pairs reproducibly amplified target amplicons, and 61 of these primer pairs detected significant polymorphism among 28 kenaf accessions. Thus, in this study, we have developed large-scale SSR markers for kenaf, and this new resource will facilitate construction of genetic linkage maps, investigation of fiber growth and development in kenaf, and also be of value to novel gene discovery and functional genomic studies. PMID:26960153

  1. An ordered EST catalogue and gene expression profiles of cassava (Manihot esculenta) at key growth stages.

    PubMed

    Li, You-Zhi; Pan, Ying-Hua; Sun, Chang-Bin; Dong, Hai-Tao; Luo, Xing-Lu; Wang, Zhi-Qiang; Tang, Ji-Liang; Chen, Baoshan

    2010-12-01

    A cDNA library was constructed from the root tissues of cassava variety Huanan 124 at the root bulking stage. A total of 9,600 cDNA clones from the library were sequenced with single-pass from the 5'-terminus to establish a catalogue of expressed sequence tags (ESTs). Assembly of the resulting EST sequences resulted in 2,878 putative unigenes. Blastn analysis showed that 62.6% of the unigenes matched with known cassava ESTs and the rest had no 'hits' against the cassava database in the integrative PlantGDB database. Blastx analysis showed that 1,715 (59.59%) of the unigenes matched with one or more GenBank protein entries and 1,163 (40.41%) had no 'hits'. A cDNA microarray with 2,878 unigenes was developed and used to analyze gene expression profiling of Huanan 124 at key growth stages including seedling, formation of root system, root bulking, and starch maturity. Array data analysis revealed that (1) the higher ratio of up-regulated ribosome-related genes was accompanied by a high ratio of up-regulated ubiquitin, proteasome-related and protease genes in cassava roots; (2) starch formation and degradation simultaneously occur at the early stages of root development but starch degradation is declined partially due to decrease in UDP-glucose dehydrogenase activity with root maturity; (3) starch may also be synthesized in situ in roots; (4) starch synthesis, translocation, and accumulation are also associated probably with signaling pathways that parallel Wnt, LAM, TCS and ErbB signaling pathways in animals; (5) constitutive expression of stress-responsive genes may be due to the adaptation of cassava to harsh environments during long-term evolution.

  2. New constraints and discovery potential of sub-GeV dark matter with xenon detectors

    NASA Astrophysics Data System (ADS)

    McCabe, Christopher

    2017-08-01

    Existing xenon dark matter (DM) direct detection experiments can probe the DM-nucleon interaction of DM with a sub-GeV mass through a search for photon emission from the recoiling xenon atom. We show that LUX's constraints on sub-GeV DM, which utilize the scintillation (S1) and ionization (S2) signals, are approximately 3 orders of magnitude more stringent than previous xenon constraints in this mass range, derived from the XENON10 and XENON100 S2-only searches. The new LUX constraints provide the most stringent direct detection constraints for DM particles with a mass below 0.5 GeV. In addition, the photon emission signal in LUX and its successor LZ maintain the discrimination between background and signal events so that an unambiguous discovery of sub-GeV DM is possible. We show that LZ has the potential to reconstruct the DM mass with ≃20 % accuracy for particles lighter than 0.5 GeV.

  3. Measuring double-electron capture with liquid xenon experiments

    NASA Astrophysics Data System (ADS)

    Mei, D.-M.; Marshall, I.; Wei, W.-Z.; Zhang, C.

    2014-01-01

    We investigate the possibilities of observing the decay mode for 124Xe in which two electrons are captured, two neutrinos are emitted, and the final daughter nucleus is in its ground state, using dark matter experiments with liquid xenon. The first upper limit of the decay half-life is calculated to be 1.66 × 1021 years at a 90% confidence level (C.L.) obtained with the published background data from the XENON100 experiment. Employing a known background model from the large underground xenon (LUX) experiment, we predict that the detection of double-electron capture of 124Xe to the ground state of 124Te with LUX will have approximately 115 events, assuming a half-life of 2.9 × 1021 years. We conclude that measuring 124Xe 2ν double-electron capture to the ground state of 124Te can be performed more precisely with the proposed LUX-Zeplin (LZ) experiment.

  4. Signal yields, energy resolution, and recombination fluctuations in liquid xenon

    NASA Astrophysics Data System (ADS)

    Akerib, D. S.; Alsum, S.; Araújo, H. M.; Bai, X.; Bailey, A. J.; Balajthy, J.; Beltrame, P.; Bernard, E. P.; Bernstein, A.; Biesiadzinski, T. P.; Boulton, E. M.; Bramante, R.; Brás, P.; Byram, D.; Cahn, S. B.; Carmona-Benitez, M. C.; Chan, C.; Chiller, A. A.; Chiller, C.; Currie, A.; Cutter, J. E.; Davison, T. J. R.; Dobi, A.; Dobson, J. E. Y.; Druszkiewicz, E.; Edwards, B. N.; Faham, C. H.; Fiorucci, S.; Gaitskell, R. J.; Gehman, V. M.; Ghag, C.; Gibson, K. R.; Gilchriese, M. G. D.; Hall, C. R.; Hanhardt, M.; Haselschwardt, S. J.; Hertel, S. A.; Hogan, D. P.; Horn, M.; Huang, D. Q.; Ignarra, C. M.; Ihm, M.; Jacobsen, R. G.; Ji, W.; Kamdin, K.; Kazkaz, K.; Khaitan, D.; Knoche, R.; Larsen, N. A.; Lee, C.; Lenardo, B. G.; Lesko, K. T.; Lindote, A.; Lopes, M. I.; Manalaysay, A.; Mannino, R. L.; Marzioni, M. F.; McKinsey, D. N.; Mei, D.-M.; Mock, J.; Moongweluwan, M.; Morad, J. A.; Murphy, A. St. J.; Nehrkorn, C.; Nelson, H. N.; Neves, F.; O'Sullivan, K.; Oliver-Mallory, K. C.; Palladino, K. J.; Pease, E. K.; Phelps, P.; Reichhart, L.; Rhyne, C.; Shaw, S.; Shutt, T. A.; Silva, C.; Solmaz, M.; Solovov, V. N.; Sorensen, P.; Stephenson, S.; Sumner, T. J.; Szydagis, M.; Taylor, D. J.; Taylor, W. C.; Tennyson, B. P.; Terman, P. A.; Tiedt, D. R.; To, W. H.; Tripathi, M.; Tvrznikova, L.; Uvarov, S.; Verbus, J. R.; Webb, R. C.; White, J. T.; Whitis, T. J.; Witherell, M. S.; Wolfs, F. L. H.; Xu, J.; Yazdani, K.; Young, S. K.; Zhang, C.; LUX Collaboration

    2017-01-01

    This work presents an analysis of monoenergetic electronic recoil peaks in the dark-matter-search and calibration data from the first underground science run of the Large Underground Xenon (LUX) detector. Liquid xenon charge and light yields for electronic recoil energies between 5.2 and 661.7 keV are measured, as well as the energy resolution for the LUX detector at those same energies. Additionally, there is an interpretation of existing measurements and descriptions of electron-ion recombination fluctuations in liquid xenon as limiting cases of a more general liquid xenon recombination fluctuation model. Measurements of the standard deviation of these fluctuations at monoenergetic electronic recoil peaks exhibit a linear dependence on the number of ions for energy deposits up to 661.7 keV, consistent with previous LUX measurements between 2 and 16 keV with 3H. We highlight similarities in liquid xenon recombination for electronic and nuclear recoils with a comparison of recombination fluctuations measured with low-energy calibration data.

  5. Regulated bioluminescence as a tool for bioremediation process monitoring and control of bacterial cultures

    NASA Technical Reports Server (NTRS)

    Burlage, Robert S.; Heitzer, Armin; Digrazia, Philip M.

    1991-01-01

    An effective on-line monitoring technique for toxic waste bioremediation using bioluminescent microorganisms has shown great potential for the description and optimization of biological processes. The lux genes of the bacterium Vibrio fischeri are used by this species to produce visible light. The lux genes can be genetically fused to the control region of a catabolic gene, with the result that bioluminescence is produced whenever the catabolic gene is induced. Thus the detection of light from a sample indicates that genetic expression from a specific gene is occurring. This technique was used to monitor biodegradation of specific contaminants from waste sites. For these studies, fusions between the lux genes and the operons for naphthalene and toluene/xylene degradation were constructed. Strains carrying one of these fusions respond sensitively and specifically to target substrates. Bioluminescence from these cultures can be rapidly measured in a nondestructive and noninvasive manner. The potential for this technique in this and other biological systems is discussed.

  6. Light without substrate amendment: the bacterial luciferase gene cassette as a mammalian bioreporter

    NASA Astrophysics Data System (ADS)

    Close, Dan M.; Xu, Tingting; Smartt, Abby E.; Jegier, Pat; Ripp, Steven A.; Sayler, Gary S.

    2011-06-01

    Bioluminescent production represents a facile method for bioreporter detection in mammalian tissues. The lack of endogenous bioluminescent reactions in these tissues allows for high signal to noise ratios even at low signal strength compared to fluorescent signal detection. While the luciferase enzymes commonly employed for bioluminescent detection are those from class Insecta (firefly and click beetle luciferases), these are handicapped in that they require concurrent administration of a luciferin compound to elicit a bioluminescent signal. The bacterial luciferase (lux) gene cassette offers the advantages common to other bioluminescent proteins, but is simultaneously capable of synthesizing its own luciferin substrates using endogenously available cellular compounds. The longstanding shortcoming of the lux cassette has been its recalcitrance to function in the mammalian cellular environment. This paper will present an overview of the work completed to date to overcome this limitation and provide examples of mammalian lux-based bioreporter technologies that could provide the framework for advanced, biomedically relevant real-time sensor development.

  7. Dose-response relationships for resetting of human circadian clock by light

    NASA Technical Reports Server (NTRS)

    Boivin, D. B.; Duffy, J. F.; Kronauer, R. E.; Czeisler, C. A.

    1996-01-01

    Since the first report in unicells, studies across diverse species have demonstrated that light is a powerful synchronizer which resets, in an intensity-dependent manner, endogenous circadian pacemakers. Although it is recognized that bright light (approximately 7,000 to 13,000 lux) is an effective circadian synchronizer in humans, it is widely believed that the human circadian pacemaker is insensitive to ordinary indoor illumination (approximately 50-300 lux). It has been proposed that the relationship between the resetting effect of light and its intensity follows a compressive nonlinear function, such that exposure to lower illuminances still exerts a robust effect. We therefore undertook a series of experiments which support this hypothesis and report here that light of even relatively low intensity (approximately 180 lux) significantly phase-shifts the human circadian pacemaker. Our results clearly demonstrate that humans are much more sensitive to light than initially suspected and support the conclusion that they are not qualitatively different from other mammals in their mechanism of circadian entrainment.

  8. Towards the understanding of the cocoa transcriptome: Production and analysis of an exhaustive dataset of ESTs of Theobroma cacao L. generated from various tissues and under various conditions

    PubMed Central

    Argout, Xavier; Fouet, Olivier; Wincker, Patrick; Gramacho, Karina; Legavre, Thierry; Sabau, Xavier; Risterucci, Ange Marie; Da Silva, Corinne; Cascardo, Julio; Allegre, Mathilde; Kuhn, David; Verica, Joseph; Courtois, Brigitte; Loor, Gaston; Babin, Regis; Sounigo, Olivier; Ducamp, Michel; Guiltinan, Mark J; Ruiz, Manuel; Alemanno, Laurence; Machado, Regina; Phillips, Wilberth; Schnell, Ray; Gilmour, Martin; Rosenquist, Eric; Butler, David; Maximova, Siela; Lanaud, Claire

    2008-01-01

    Background Theobroma cacao L., is a tree originated from the tropical rainforest of South America. It is one of the major cash crops for many tropical countries. T. cacao is mainly produced on smallholdings, providing resources for 14 million farmers. Disease resistance and T. cacao quality improvement are two important challenges for all actors of cocoa and chocolate production. T. cacao is seriously affected by pests and fungal diseases, responsible for more than 40% yield losses and quality improvement, nutritional and organoleptic, is also important for consumers. An international collaboration was formed to develop an EST genomic resource database for cacao. Results Fifty-six cDNA libraries were constructed from different organs, different genotypes and different environmental conditions. A total of 149,650 valid EST sequences were generated corresponding to 48,594 unigenes, 12,692 contigs and 35,902 singletons. A total of 29,849 unigenes shared significant homology with public sequences from other species. Gene Ontology (GO) annotation was applied to distribute the ESTs among the main GO categories. A specific information system (ESTtik) was constructed to process, store and manage this EST collection allowing the user to query a database. To check the representativeness of our EST collection, we looked for the genes known to be involved in two different metabolic pathways extensively studied in other plant species and important for T. cacao qualities: the flavonoid and the terpene pathways. Most of the enzymes described in other crops for these two metabolic pathways were found in our EST collection. A large collection of new genetic markers was provided by this ESTs collection. Conclusion This EST collection displays a good representation of the T. cacao transcriptome, suitable for analysis of biochemical pathways based on oligonucleotide microarrays derived from these ESTs. It will provide numerous genetic markers that will allow the construction of a high

  9. Towards the understanding of the cocoa transcriptome: Production and analysis of an exhaustive dataset of ESTs of Theobroma cacao L. generated from various tissues and under various conditions.

    PubMed

    Argout, Xavier; Fouet, Olivier; Wincker, Patrick; Gramacho, Karina; Legavre, Thierry; Sabau, Xavier; Risterucci, Ange Marie; Da Silva, Corinne; Cascardo, Julio; Allegre, Mathilde; Kuhn, David; Verica, Joseph; Courtois, Brigitte; Loor, Gaston; Babin, Regis; Sounigo, Olivier; Ducamp, Michel; Guiltinan, Mark J; Ruiz, Manuel; Alemanno, Laurence; Machado, Regina; Phillips, Wilberth; Schnell, Ray; Gilmour, Martin; Rosenquist, Eric; Butler, David; Maximova, Siela; Lanaud, Claire

    2008-10-30

    Theobroma cacao L., is a tree originated from the tropical rainforest of South America. It is one of the major cash crops for many tropical countries. T. cacao is mainly produced on smallholdings, providing resources for 14 million farmers. Disease resistance and T. cacao quality improvement are two important challenges for all actors of cocoa and chocolate production. T. cacao is seriously affected by pests and fungal diseases, responsible for more than 40% yield losses and quality improvement, nutritional and organoleptic, is also important for consumers. An international collaboration was formed to develop an EST genomic resource database for cacao. Fifty-six cDNA libraries were constructed from different organs, different genotypes and different environmental conditions. A total of 149,650 valid EST sequences were generated corresponding to 48,594 unigenes, 12,692 contigs and 35,902 singletons. A total of 29,849 unigenes shared significant homology with public sequences from other species.Gene Ontology (GO) annotation was applied to distribute the ESTs among the main GO categories.A specific information system (ESTtik) was constructed to process, store and manage this EST collection allowing the user to query a database.To check the representativeness of our EST collection, we looked for the genes known to be involved in two different metabolic pathways extensively studied in other plant species and important for T. cacao qualities: the flavonoid and the terpene pathways. Most of the enzymes described in other crops for these two metabolic pathways were found in our EST collection.A large collection of new genetic markers was provided by this ESTs collection. This EST collection displays a good representation of the T. cacao transcriptome, suitable for analysis of biochemical pathways based on oligonucleotide microarrays derived from these ESTs. It will provide numerous genetic markers that will allow the construction of a high density gene map of T. cacao

  10. Gene identification and analysis of transcripts differentially regulated in fracture healing by EST sequencing in the domestic sheep.

    PubMed

    Hecht, Jochen; Kuhl, Heiner; Haas, Stefan A; Bauer, Sebastian; Poustka, Albert J; Lienau, Jasmin; Schell, Hanna; Stiege, Asita C; Seitz, Volkhard; Reinhardt, Richard; Duda, Georg N; Mundlos, Stefan; Robinson, Peter N

    2006-07-05

    The sheep is an important model animal for testing novel fracture treatments and other medical applications. Despite these medical uses and the well known economic and cultural importance of the sheep, relatively little research has been performed into sheep genetics, and DNA sequences are available for only a small number of sheep genes. In this work we have sequenced over 47 thousand expressed sequence tags (ESTs) from libraries developed from healing bone in a sheep model of fracture healing. These ESTs were clustered with the previously available 10 thousand sheep ESTs to a total of 19087 contigs with an average length of 603 nucleotides. We used the newly identified sequences to develop RT-PCR assays for 78 sheep genes and measured differential expression during the course of fracture healing between days 7 and 42 postfracture. All genes showed significant shifts at one or more time points. 23 of the genes were differentially expressed between postfracture days 7 and 10, which could reflect an important role for these genes for the initiation of osteogenesis. The sequences we have identified in this work are a valuable resource for future studies on musculoskeletal healing and regeneration using sheep and represent an important head-start for genomic sequencing projects for Ovis aries, with partial or complete sequences being made available for over 5,800 previously unsequenced sheep genes.

  11. p38 Mitogen-Activated Protein Kinase in Metastasis Associated with Transforming Growth Factor Beta

    DTIC Science & Technology

    2006-06-01

    Functional Analysis of cells • Expression of HA-tagged TβRI • Signaling (p-Smad2, p- HSP27 , p-p38) • Transcription (SBE-Lux, 3TP-Lux) • Proliferation...when they also affected lls expressing DN-p38alpha phosphorylation of HSP27 was effectively blocked (data not shown). However, cells e studies show...231-ALK5-T204D cells treated with kinase inhibitors U0126, SB202190, SP600125 (JNK). (B) Immunoblot of phospho-Smad2/3, phospho- HSP27 , and alpha

  12. The Ever-Est Virtual Research Environment Infrastructure for Marine - the Sea Monitoring Virtual Research Community (vrc) Use Case

    NASA Astrophysics Data System (ADS)

    Foglini, F.

    2016-12-01

    The EVER-EST project aims to develop a generic Virtual Research Environment (VRE) tailored to the needs and validated by the Earth Science domain. To achieve this the EVER-EST VRE provides earth scientists with the means to seamlessly manage both the data involved in their computationally intensive disciplines and the scientific methods applied in their observations and modellings, which lead to the specific results that need to be attributable, validated and shared within the community e.g. in the form of scholarly communications. Central to this approach is the concept of Research Objects (ROs) as semantically rich aggregations of resources that bring together data, methods and people in scientific investigations. ROs enable the creation of digital artifacts that can encapsulate scientific knowledge and provide a mechanism for sharing and discovering assets of reusable research and scientific assets as first-class citizens. The EVER-EST VRE is the first RO-centric native infrastructure leveraging the notion of ROs and their application in observational rather than experimental disciplines and particularly in Earth Science. The Institute of MARine Science (ISMAR-CNR) is a scientific partner of the EVER-EST project providing useful and applicable contributions to the identification and definition of variables indicated by the European Commission in the Marine Strategy Framework Directive (MSFD) to achieve the Good Environment Status (GES). The VRC is willing to deliver practical methods, procedures and protocols to support coherent and widely accepted interpretation of the MSFD. The use case deal with 1. the Posidonia meadows along the Apulian coast, 2. the deep-sea corals along the Apulian continenatal slope and 3. the jellyfish abundance in the Italian water. The SeaMonitoring VRC created specific RO for asesing deep sea corals suitabilty, Posidonia meadows occurrences and for detecting jelly fish density aloing the italian coast. The VRC developed specific RO

  13. Genetic diversity and relationships among different tomato varieties revealed by EST-SSR markers.

    PubMed

    Korir, N K; Diao, W; Tao, R; Li, X; Kayesh, E; Li, A; Zhen, W; Wang, S

    2014-01-08

    The genetic diversity and relationship of 42 tomato varieties sourced from different geographic regions was examined with EST-SSR markers. The genetic diversity was between 0.18 and 0.77, with a mean of 0.49; the polymorphic information content ranged from 0.17 to 0.74, with a mean of 0.45. This indicates a fairly high degree of diversity among these tomato varieties. Based on the cluster analysis using unweighted pair-group method with arithmetic average (UPGMA), all the tomato varieties fell into 5 groups, with no obvious geographical distribution characteristics despite their diverse sources. The principal component analysis (PCA) supported the clustering result; however, relationships among varieties were more complex in the PCA scatterplot than in the UPGMA dendrogram. This information about the genetic relationships between these tomato lines helps distinguish these 42 varieties and will be useful for tomato variety breeding and selection. We confirm that the EST-SSR marker system is useful for studying genetic diversity among tomato varieties. The high degree of polymorphism and the large number of bands obtained per assay shows that SSR is the most informative marker system for tomato genotyping for purposes of rights/protection and for the tomato industry in general. It is recommended that these varieties be subjected to identification using an SSR-based manual cultivar identification diagram strategy or other easy-to-use and referable methods so as to provide a complete set of information concerning genetic relationships and a readily usable means of identifying these varieties.

  14. The Agr-Like Quorum Sensing System Is Required for Pathogenesis of Necrotic Enteritis Caused by Clostridium perfringens in Poultry.

    PubMed

    Yu, Qiang; Lepp, Dion; Mehdizadeh Gohari, Iman; Wu, Tao; Zhou, Hongzhuan; Yin, Xianhua; Yu, Hai; Prescott, John F; Nie, Shao-Ping; Xie, Ming-Yong; Gong, Joshua

    2017-06-01

    Clostridium perfringens encodes at least two different quorum sensing (QS) systems, the Agr-like and LuxS, and recent studies have highlighted their importance in the regulation of toxin production and virulence. The role of QS in the pathogenesis of necrotic enteritis (NE) in poultry and the regulation of NetB, the key toxin involved, has not yet been investigated. We have generated isogenic agrB -null and complemented strains from parent strain CP1 and demonstrated that the virulence of the agrB -null mutant was strongly attenuated in a chicken NE model system and restored by complementation. The production of NetB, a key NE-associated toxin, was dramatically reduced in the agrB mutant at both the transcriptional and protein levels, though not in a luxS mutant. Transwell assays confirmed that the Agr-like QS system controls NetB production through a diffusible signal. Global gene expression analysis of the agrB mutant identified additional genes modulated by Agr-like QS, including operons related to phospholipid metabolism and adherence, which may also play a role in NE pathogenesis. This study provides the first evidence that the Agr-like QS system is critical for NE pathogenesis and identifies a number of Agr-regulated genes, most notably netB , that are potentially involved in mediating its effects. The Agr-like QS system thus may serve as a target for developing novel interventions to prevent NE in chickens. © Crown copyright 2017.

  15. Study on Suitable Light Conditions and Efficient Lipid Extraction Technologies for Biodiesel Production Based on Microalgae

    NASA Astrophysics Data System (ADS)

    Wang, Yao; Zhang, Qingtao; Sun, Yuan; Yang, Chengjia

    2018-01-01

    As a new generation biodiesel feedstock, microalgae have most potential to replace fossil fuel. However, the limited scale and high cost are two bottleneck problems. Efficient microwave-assisted lipid extraction technologies and suitable light conditions for Chlorella Sorokiniana need further study for lowering the cost. In this study, three photoperiod groups(24L:0D, 12L:12D, 0L:24D), three illumination intensity groups (1800 lux, 3600 lux, 5400 lux)and four light spectrum groups (Red, green, blue, and white) were used to culture Chlorella Sorokiniana to investigate those effects on algae growth rate and biomass accumulation. The suitable microwave treatment was also studied to achieve an optimizing quantum fracturing technology. 400 w, 750 w and 1000 w microwave power were set and 60 °C, 75 °C, 90 °C microwave conditions were investigated. The results showed that Chlorella Sorokiniana under 24L:0D photoperiod with 5400 lux white light can achieve better growth rate. The 90 °C / 1000w microwave treatment was identified as the most simple, easy, and effective way for lipid extraction from Chlorella Sorokiniana. As the raw material of biodiesel production, C18:1, C18:2 and C18:3 have accounted for important components of fatty acid in Chlorella Sorokiniana. Therefore, Chlorella Sorokiniana is a good raw material for the production of good quality biodiesel under suitable and efficient technologies.

  16. Daytime light intensity affects seasonal timing via changes in the nocturnal melatonin levels

    NASA Astrophysics Data System (ADS)

    Kumar, Vinod; Rani, Sangeeta; Malik, Shalie; Trivedi, Amit K.; Schwabl, Ingrid; Helm, Barbara; Gwinner, Eberhard

    2007-08-01

    Daytime light intensity can affect the photoperiodic regulation of the reproductive cycle in birds. The actual way by which light intensity information is transduced is, however, unknown. We postulate that transduction of the light intensity information is mediated by changes in the pattern of melatonin secretion. This study, therefore, investigated the effects of high and low daytime light intensities on the daily melatonin rhythm of Afro-tropical stonechats ( Saxicola torquata axillaris) in which seasonal changes in daytime light intensity act as a zeitgeber of the circannual rhythms controlling annual reproduction and molt. Stonechats were subjected to light conditions simulated as closely as possible to native conditions near the equator. Photoperiod was held constant at 12.25 h of light and 11.75 h of darkness per day. At intervals of 2.5 to 3.5 weeks, daytime light intensity was changed from bright (12,000 lux at one and 2,000 lux at the other perch) to dim (1,600 lux at one and 250 lux at the other perch) and back to the original bright light. Daily plasma melatonin profiles showed that they were linked with changes in daytime light intensity: Nighttime peak and total nocturnal levels were altered when transitions between light conditions were made, and these changes were significant when light intensity was changed from dim to bright. We suggest that daytime light intensity could affect seasonal timing via changes in melatonin profiles.

  17. RpoS induces expression of the Vibrio anguillarum quorum-sensing regulator VanT.

    PubMed

    Weber, Barbara; Croxatto, Antony; Chen, Chang; Milton, Debra L

    2008-03-01

    In vibrios, regulation of the Vibrio harveyi-like LuxR transcriptional activators occurs post-transcriptionally via small regulatory RNAs (sRNAs) that destabilize the luxR mRNA at a low cell population, eliminating expression of LuxR. Expression of the sRNAs is modulated by the vibrio quorum-sensing phosphorelay systems. However, vanT mRNA, which encodes a LuxR homologue in Vibrio anguillarum, is abundant at low and high cell density, indicating that VanT expression may be regulated via additional mechanisms. In this study, Western analyses showed that VanT was expressed throughout growth with a peak of expression during late exponential growth. VanO induced partial destabilization of vanT mRNA via activation of at least one Qrr sRNA. Interestingly, the sigma factor RpoS significantly stabilized vanT mRNA and induced VanT expression during late exponential growth. This induction was in part due to RpoS repressing expression of Hfq, an RNA chaperone. RpoS is not part of the quorum-sensing regulatory cascade since RpoS did not regulate expression or activity of VanO, and RpoS was not regulated by VanO or VanT. VanT and RpoS were needed for survival following UV irradiation and for pigment and metalloprotease production, suggesting that RpoS works with the quorum-sensing systems to modulate expression of VanT, which regulates survival and stress responses.

  18. The response of Serratia marcescens JG to environmental changes by quorum sensing system.

    PubMed

    Sun, Shu-Jing; Liu, Hui-Jun; Weng, Cai-Hong; Lai, Chun-Fen; Ai, Liu-Ying; Liu, Yu-Chen; Zhu, Hu

    2016-08-01

    Many bacterial cells are known to regulate their cooperative behaviors and physiological processes through a molecular mechanism called quorum sensing. Quorum sensing in Serratia marcescens JG is mediated by the synthesis of autoinducer 2 (AI-2) which is a furanosyl borate diester. In this study, the response of quorum sensing in S. marcescens JG to environment changes such as the initial pH, carbon sources and boracic acid was investigated by a bioreporter and real-time PCR analysis. The results show that glucose can affect AI-2 synthesis to the greatest extent, and 2.0 % glucose can stimulate S. marcescens JG to produce more AI-2, with a 3.5-fold increase in activity compared with control culture. Furthermore, the response of quorum sensing to changes in glucose concentration was performed by changing the amount of luxS RNA transcripts. A maximum of luxS transcription appeared during the exponential growth phase when the glucose concentration was 20.0 g/L. AI-2 production was also slightly impacted by the low initial pH. It is significant for us that the addition of boracic acid at microdosage (0.1-0.2 g/L) can also induce AI-2 synthesis, which probably demonstrated the feasible fact that the 4,5-dihydroxy-2, 3-pentanedione cyclizes by the addition of borate and the loss of water, is hydrated and is converted to the final AI-2 in S. marcescens JG.

  19. Early Career: The search for weakly interacting dark matter with liquid xenon

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hall, Carter

    2017-02-08

    We report results from a search for weakly interacting dark matter particles obtained with the LUX experiment. LUX was located at a depth of 4850 feet at the Sanford Underground Research Facility in Lead, South Dakota from 2013 through 2016. It found no evidence for dark matter particle interactions and set new constraints on the properties of such particles for masses between 6 GeV and 100 TeV. The work reported here also characterized the performance of such experiments by developing a new calibration technique based upon a tritium beta decay source.

  20. Mitochondrial DNA Marker EST00083 Is Not Associated with High vs. Average IQ in a German Sample.

    ERIC Educational Resources Information Center

    Moises, Hans W.; Yang, Liu; Kohnke, Michael; Vetter, Peter; Neppert, Jurgen; Petrill, Stephen A.; Plomin, Robert

    1998-01-01

    Tested the association of a mitochondrial DNA marker (EST00083) with high IQ in a sample of 47 German adults with high IQ scores and 77 adults with IQs estimated at lower than 110. Results do not support the hypothesis that high IQ is associated with this marker. (SLD)

  1. PineElm_SSRdb: a microsatellite marker database identified from genomic, chloroplast, mitochondrial and EST sequences of pineapple (Ananas comosus (L.) Merrill).

    PubMed

    Chaudhary, Sakshi; Mishra, Bharat Kumar; Vivek, Thiruvettai; Magadum, Santoshkumar; Yasin, Jeshima Khan

    2016-01-01

    Simple Sequence Repeats or microsatellites are resourceful molecular genetic markers. There are only few reports of SSR identification and development in pineapple. Complete genome sequence of pineapple available in the public domain can be used to develop numerous novel SSRs. Therefore, an attempt was made to identify SSRs from genomic, chloroplast, mitochondrial and EST sequences of pineapple which will help in deciphering genetic makeup of its germplasm resources. A total of 359511 SSRs were identified in pineapple (356385 from genome sequence, 45 from chloroplast sequence, 249 in mitochondrial sequence and 2832 from EST sequences). The list of EST-SSR markers and their details are available in the database. PineElm_SSRdb is an open source database available for non-commercial academic purpose at http://app.bioelm.com/ with a mapping tool which can develop circular maps of selected marker set. This database will be of immense use to breeders, researchers and graduates working on Ananas spp. and to others working on cross-species transferability of markers, investigating diversity, mapping and DNA fingerprinting.

  2. Development of 101 novel EST-derived single nucleotide polymorphism markers for Zhikong scallop ( Chlamys farreri)

    NASA Astrophysics Data System (ADS)

    Li, Jiqin; Bao, Zhenmin; Li, Ling; Wang, Xiaojian; Wang, Shi; Hu, Xiaoli

    2013-09-01

    Zhikong scallop ( Chlamys farreri) is an important maricultured species in China. Many researches on this species, such as population genetics and QTL fine-mapping, need a large number of molecular markers. In this study, based on the expressed sequence tags (EST), a total of 300 putative single nucleotide polymorphisms (SNPs) were selected and validated using high resolution melting (HRM) technology with unlabeled probe. Of them, 101 (33.7%) were found to be polymorphic in 48 individuals from 4 populations. Further evaluation with 48 individuals from Qingdao population showed that all the polymorphic loci had two alleles with the minor allele frequency ranged from 0.046 to 0.500. The observed and expected heterozygosities ranged from 0.000 to 0.925 and from 0.089 to 0.505, respectively. Fifteen loci deviated significantly from Hardy-Weinberg equilibrium and significant linkage disequilibrate was detected in one pair of markers. BLASTx gave significant hits for 72 of the 101 polymorphic SNP-containing ESTs. Thirty four polymorphic SNP loci were predicted to be non-synonymous substitutions as they caused either the change of codons (33 SNPs) or pretermination of translation (1 SNP). The markers developed can be used for the population studies and genetic improvement on Zhikong scallop.

  3. Nighttime dim light exposure alters the responses of the circadian system.

    PubMed

    Shuboni, D; Yan, L

    2010-11-10

    The daily light dark cycle is the most salient entraining factor for the circadian system. However, in modern society, darkness at night is vanishing as light pollution steadily increases. The impact of brighter nights on wild life ecology and human physiology is just now being recognized. In the present study, we tested the possible detrimental effects of dim light exposure on the regulation of circadian rhythms, using CD1 mice housed in light/dim light (LdimL, 300 lux:20 lux) or light/dark (LD, 300 lux:1 lux) conditions. We first examined the expression of clock genes in the suprachiasmatic nucleus (SCN), the locus of the principal brain clock, in the animals of the LD and LdimL groups. Under the entrained condition, there was no difference in PER1 peak expression between the two groups, but at the trough of the PER 1 rhythm, there was an increase in PER1 in the LdimL group, indicating a decrease in the amplitude of the PER1 rhythm. After a brief light exposure (30 min, 300 lux) at night, the light-induced expression of mPer1 and mPer2 genes was attenuated in the SCN of LdimL group. Next, we examined the behavioral rhythms by monitoring wheel-running activity to determine whether the altered responses in the SCN of LdimL group have behavioral consequence. Compared to the LD controls, the LdimL group showed increased daytime activity. After being released into constant darkness, the LdimL group displayed shorter free-running periods. Furthermore, following the light exposure, the phase shifting responses were smaller in the LdimL group. The results indicate that nighttime dim light exposure can cause functional changes of the circadian system, and suggest that altered circadian function could be one of the mechanisms underlying the adverse effects of light pollution on wild life ecology and human physiology. Copyright © 2010 IBRO. Published by Elsevier Ltd. All rights reserved.

  4. Light colour and intensity alters reproductive/seasonal responses in Japanese quail.

    PubMed

    Yadav, Suneeta; Chaturvedi, Chandra Mohini

    2015-08-01

    An extensive literature is available on the photoperiodic responses of avian species but studies on light colour and wavelength from light emitting diode (LED) sources on reproduction are limited. Hence, an experiment was designed to study the effect of different colours and intensities of light on the reproductive responses of Japanese quail. Three-week old quail were exposed to five different light conditions with a long photoperiod (LD 16:8): WT (white fluorescent light 100 lux as control), W LED (white light emitting diode, 30 lux), B LED (blue LED, 30 lux), G LED (green LED, 30 lux) and R-LED (red LED, 30 lux). The cloacal gland size, an indicator of androgenic activity, was monitored weekly. The results indicated an early initiation of gonadal growth in WT quail which continued and maintained a plateau throughout the period of study. On the other hand, in general low intensity light, there was a decreased amplitude of the reproductive cycle and the quail exposed to different colour lights (green, red and blue lights) used different incubation times to initiate their gonadal growth and exhibited a gonadal cycle of a different duration up to 15.5 weeks. Thereafter, the gonad of quail of all the LED groups started developing again (including the blue LED exposed quail which remained undeveloped until this age) and attained the increased degree of growth until 26.5 weeks of age. During the second cycle, gonads of green and red light exposed quail continued to increase and maintained a plateau of development similar to WT exposed control while white and blue LED exposed quail exhibited spontaneous regression and attained complete sexual quiescence. Based on our study, it is suggested that long term exposure to blue LED light of low intensity may induce gonadal regression even under long-day conditions (LD 16:8), while exposure to green and red lights appears to maintain a constant photosensitivity after one complete gonadal cycle. Copyright © 2015 Elsevier Inc

  5. Laryngoscope illuminance in a tertiary children's hospital: implications for quality laryngoscopy.

    PubMed

    Volsky, Peter G; Murphy, Michael K; Darrow, David H

    2014-07-01

    Laryngoscopes are used by otolaryngologists in a variety of hospital emergency and critical care settings. However, only rarely have quality-related aspects of laryngoscope function and application been studied. To compare the illuminance of laryngoscopes commonly used in a hospital setting to established standards and to assess the potential effects of maintenance practices on laryngoscope illuminance. Observational study of laryngoscope light output and cross-sectional survey of individuals charged with laryngoscope maintenance in a tertiary care children's hospital. Illuminance was chosen as the unit of measurement (lux). Laryngoscopes in the operating room, emergency department, and pediatric intensive care unit were tested according to a standard technique. Illuminance standards for laryngoscopes, published by the International Organization for Standardization (ISO) (500 lux) and in the medical literature (867 lux) were used as benchmarks. Mean laryngoscope illuminance by type of laryngoscope and light source and percentage of laryngoscopes with illuminance below established standards as well as nonfunctioning units. Maintenance practices were evaluated as a secondary outcome. A total of 319 laryngoscopes were tested; 283 were incandescent bulb units used by anesthesiologists, emergency physicians, and intensivists and 36 were xenon light units used by otolaryngologists. Mean (SD) illuminance was 1330 (1160) lux in the incandescent group and 16,600 (13,000) lux in the xenon group (P < .001). Substandard illuminance was observed only in the incandescent group, in 29% to 43% of laryngoscopes; 5% of the incandescent group did not turn on at all. Maintenance of laryngoscopes was performed on a reactive rather than a preventive basis. At our facility, approximately one-third of incandescent laryngoscopes exhibited substandard light output. On the basis of these findings, our hospital has converted all of its incandescent laryngoscopes to light-emitting diode (LED

  6. ESTE: Verification of Portable Optical and Thermal Imaging Devices for Leak Detection at Petroleum Refineries and Chemical Plants

    EPA Science Inventory

    This is an ESTE project summary brief. EPA’s Environmental Technology Verification Program (ETV) is verifying the performance of portable optical and thermal imaging devices for leak detection at petroleum refineries and chemical plans. Industrial facilities, such as chemical p...

  7. An Ambystoma mexicanum EST sequencing project: analysis of 17,352 expressed sequence tags from embryonic and regenerating blastema cDNA libraries

    PubMed Central

    Habermann, Bianca; Bebin, Anne-Gaelle; Herklotz, Stephan; Volkmer, Michael; Eckelt, Kay; Pehlke, Kerstin; Epperlein, Hans Henning; Schackert, Hans Konrad; Wiebe, Glenis; Tanaka, Elly M

    2004-01-01

    Background The ambystomatid salamander, Ambystoma mexicanum (axolotl), is an important model organism in evolutionary and regeneration research but relatively little sequence information has so far been available. This is a major limitation for molecular studies on caudate development, regeneration and evolution. To address this lack of sequence information we have generated an expressed sequence tag (EST) database for A. mexicanum. Results Two cDNA libraries, one made from stage 18-22 embryos and the other from day-6 regenerating tail blastemas, generated 17,352 sequences. From the sequenced ESTs, 6,377 contigs were assembled that probably represent 25% of the expressed genes in this organism. Sequence comparison revealed significant homology to entries in the NCBI non-redundant database. Further examination of this gene set revealed the presence of genes involved in important cell and developmental processes, including cell proliferation, cell differentiation and cell-cell communication. On the basis of these data, we have performed phylogenetic analysis of key cell-cycle regulators. Interestingly, while cell-cycle proteins such as the cyclin B family display expected evolutionary relationships, the cyclin-dependent kinase inhibitor 1 gene family shows an unusual evolutionary behavior among the amphibians. Conclusions Our analysis reveals the importance of a comprehensive sequence set from a representative of the Caudata and illustrates that the EST sequence database is a rich source of molecular, developmental and regeneration studies. To aid in data mining, the ESTs have been organized into an easily searchable database that is freely available online. PMID:15345051

  8. Bioinformatic analysis of ESTs collected by Sanger and pyrosequencing methods for a keystone forest tree species: oak

    PubMed Central

    2010-01-01

    Background The Fagaceae family comprises about 1,000 woody species worldwide. About half belong to the Quercus family. These oaks are often a source of raw material for biomass wood and fiber. Pedunculate and sessile oaks, are among the most important deciduous forest tree species in Europe. Despite their ecological and economical importance, very few genomic resources have yet been generated for these species. Here, we describe the development of an EST catalogue that will support ecosystem genomics studies, where geneticists, ecophysiologists, molecular biologists and ecologists join their efforts for understanding, monitoring and predicting functional genetic diversity. Results We generated 145,827 sequence reads from 20 cDNA libraries using the Sanger method. Unexploitable chromatograms and quality checking lead us to eliminate 19,941 sequences. Finally a total of 125,925 ESTs were retained from 111,361 cDNA clones. Pyrosequencing was also conducted for 14 libraries, generating 1,948,579 reads, from which 370,566 sequences (19.0%) were eliminated, resulting in 1,578,192 sequences. Following clustering and assembly using TGICL pipeline, 1,704,117 EST sequences collapsed into 69,154 tentative contigs and 153,517 singletons, providing 222,671 non-redundant sequences (including alternative transcripts). We also assembled the sequences using MIRA and PartiGene software and compared the three unigene sets. Gene ontology annotation was then assigned to 29,303 unigene elements. Blast search against the SWISS-PROT database revealed putative homologs for 32,810 (14.7%) unigene elements, but more extensive search with Pfam, Refseq_protein, Refseq_RNA and eight gene indices revealed homology for 67.4% of them. The EST catalogue was examined for putative homologs of candidate genes involved in bud phenology, cuticle formation, phenylpropanoids biosynthesis and cell wall formation. Our results suggest a good coverage of genes involved in these traits. Comparative orthologous

  9. An expressed sequence tag (EST) library for Drosophila serrata, a model system for sexual selection and climatic adaptation studies.

    PubMed

    Frentiu, Francesca D; Adamski, Marcin; McGraw, Elizabeth A; Blows, Mark W; Chenoweth, Stephen F

    2009-01-21

    The native Australian fly Drosophila serrata belongs to the highly speciose montium subgroup of the melanogaster species group. It has recently emerged as an excellent model system with which to address a number of important questions, including the evolution of traits under sexual selection and traits involved in climatic adaptation along latitudinal gradients. Understanding the molecular genetic basis of such traits has been limited by a lack of genomic resources for this species. Here, we present the first expressed sequence tag (EST) collection for D. serrata that will enable the identification of genes underlying sexually-selected phenotypes and physiological responses to environmental change and may help resolve controversial phylogenetic relationships within the montium subgroup. A normalized cDNA library was constructed from whole fly bodies at several developmental stages, including larvae and adults. Assembly of 11,616 clones sequenced from the 3' end allowed us to identify 6,607 unique contigs, of which at least 90% encoded peptides. Partial transcripts were discovered from a variety of genes of evolutionary interest by BLASTing contigs against the 12 Drosophila genomes currently sequenced. By incorporating into the cDNA library multiple individuals from populations spanning a large portion of the geographical range of D. serrata, we were able to identify 11,057 putative single nucleotide polymorphisms (SNPs), with 278 different contigs having at least one "double hit" SNP that is highly likely to be a real polymorphism. At least 394 EST-associated microsatellite markers, representing 355 different contigs, were also found, providing an additional set of genetic markers. The assembled EST library is available online at http://www.chenowethlab.org/serrata/index.cgi. We have provided the first gene collection and largest set of polymorphic genetic markers, to date, for the fly D. serrata. The EST collection will provide much needed genomic resources for

  10. Effects of Illumination Pattern during Cultivation of Fruiting Body and Bioactive Compound Production by the Caterpillar Medicinal Mushroom, Cordyceps militaris (Ascomycetes).

    PubMed

    Wu, Chiu-Yeh; Liang, Zeng-Chin; Tseng, Chin-Yin; Hu, Shu-Hui

    2016-01-01

    We investigated the effects of light intensity in the 3 cultivation stages separately-the mycelium colonization stage, the primordial initiation stage, and the fruiting stage (in order)-on fruiting body and bioactive compound production by Cordyceps militaris. In the mycelium colonization stage, rice substrates were incubated in a spawn running room at 23°C. During the primordial initiation stage, C. militaris was grown at 18°C and illuminated 12 hours/day. In the fruiting stage the temperature was 23°C, with illumination provided 12 hours/day. The highest fruiting body yield and biological efficiency were 4.06 g dry weight/bottle and 86.83%, respectively, under 1750 ± 250 lux during the second and third stages. The cordycepin content was highest during the second and third stages under 1250 ± 250 lux. The mannitol and polysaccharide contents were highest under 1250 ± 250 and 1750 ± 250 lux during the primordial initiation stage and the fruiting stage, respectively. Thus, with controlled lighting, C. militaris can be cultivated in rice-water medium to increase fruiting body yield and bioactive compound production.

  11. VizieR Online Data Catalog: Properties of late M-dwarfs (Janson+, 2014)

    NASA Astrophysics Data System (ADS)

    Janson, M.; Bergfors, C.; Brandner, W.; Kudryavtseva, N.; Hormuth, F.; Hippler, S.; Henning, T.

    2017-03-01

    The targets in this study were selected from the Lepine & Gaidos (2011, J/AJ/142/138) sample, where stars with a spectral type (SpT) estimate of M5 or later were selected if they were sufficiently bright (J <= 10.0 mag) and sufficiently far north (>-15°) to be meaningfully observed with AstraLux Norte. In total, this gave an input sample of 408 potential targets, of which 286 were actually observed. All observations in this program were acquired with the AstraLux Norte camera on the 2.2 m telescope at Calar Alto in Spain. The 2.2 m telescope is on an equatorial mount. AstraLux uses an Andor DV887-UVB camera head equipped with a thinned, back-illuminated, electron-multiplying 512 x 512 pixel monolithic CCD. The CCD is equipped with two readout registers, one for conventional readout, and one 536 stage electron multiplication register. Each of the two registers comes with its own output amplifier. All Lucky Imaging data were obtained using the electron multiplication mode, and the associated output amplifier. (3 data files).

  12. Signal yields, energy resolution, and recombination fluctuations in liquid xenon

    DOE PAGES

    Akerib, D. ?S.; Alsum, S.; Ara?jo, H. ?M.; ...

    2017-01-19

    This study presents an analysis of monoenergetic electronic recoil peaks in the dark-matter-search and calibration data from the first underground science run of the Large Underground Xenon (LUX) detector. Liquid xenon charge and light yields for electronic recoil energies between 5.2 and 661.7 keV are measured, as well as the energy resolution for the LUX detector at those same energies. Additionally, there is an interpretation of existing measurements and descriptions of electron-ion recombination fluctuations in liquid xenon as limiting cases of a more general liquid xenon recombination fluctuation model. Measurements of the standard deviation of these fluctuations at monoenergetic electronicmore » recoil peaks exhibit a linear dependence on the number of ions for energy deposits up to 661.7 keV, consistent with previous LUX measurements between 2 and 16 keV with 3H. We highlight similarities in liquid xenon recombination for electronic and nuclear recoils with a comparison of recombination fluctuations measured with low-energy calibration data.« less

  13. Comparative high-throughput transcriptome sequencing and development of SiESTa, the Silene EST annotation database

    PubMed Central

    2011-01-01

    Background The genus Silene is widely used as a model system for addressing ecological and evolutionary questions in plants, but advances in using the genus as a model system are impeded by the lack of available resources for studying its genome. Massively parallel sequencing cDNA has recently developed into an efficient method for characterizing the transcriptomes of non-model organisms, generating massive amounts of data that enable the study of multiple species in a comparative framework. The sequences generated provide an excellent resource for identifying expressed genes, characterizing functional variation and developing molecular markers, thereby laying the foundations for future studies on gene sequence and gene expression divergence. Here, we report the results of a comparative transcriptome sequencing study of eight individuals representing four Silene and one Dianthus species as outgroup. All sequences and annotations have been deposited in a newly developed and publicly available database called SiESTa, the Silene EST annotation database. Results A total of 1,041,122 EST reads were generated in two runs on a Roche GS-FLX 454 pyrosequencing platform. EST reads were analyzed separately for all eight individuals sequenced and were assembled into contigs using TGICL. These were annotated with results from BLASTX searches and Gene Ontology (GO) terms, and thousands of single-nucleotide polymorphisms (SNPs) were characterized. Unassembled reads were kept as singletons and together with the contigs contributed to the unigenes characterized in each individual. The high quality of unigenes is evidenced by the proportion (49%) that have significant hits in similarity searches with the A. thaliana proteome. The SiESTa database is accessible at http://www.siesta.ethz.ch. Conclusion The sequence collections established in the present study provide an important genomic resource for four Silene and one Dianthus species and will help to further develop Silene as a

  14. ContEst16S: an algorithm that identifies contaminated prokaryotic genomes using 16S RNA gene sequences.

    PubMed

    Lee, Imchang; Chalita, Mauricio; Ha, Sung-Min; Na, Seong-In; Yoon, Seok-Hwan; Chun, Jongsik

    2017-06-01

    Thanks to the recent advancement of DNA sequencing technology, the cost and time of prokaryotic genome sequencing have been dramatically decreased. It has repeatedly been reported that genome sequencing using high-throughput next-generation sequencing is prone to contaminations due to its high depth of sequencing coverage. Although a few bioinformatics tools are available to detect potential contaminations, these have inherited limitations as they only use protein-coding genes. Here we introduce a new algorithm, called ContEst16S, to detect potential contaminations using 16S rRNA genes from genome assemblies. We screened 69 745 prokaryotic genomes from the NCBI Assembly Database using ContEst16S and found that 594 were contaminated by bacteria, human and plants. Of the predicted contaminated genomes, 8 % were not predicted by the existing protein-coding gene-based tool, implying that both methods can be complementary in the detection of contaminations. A web-based service of the algorithm is available at www.ezbiocloud.net/tools/contest16s.

  15. La problématique du coût des nouvelles thérapeutiques en oncologie: qu'en-est-il du Maroc?

    PubMed Central

    Brahmi, Sami Aziz; Zahra, Ziani Fatima; Seddik, Youssef; Afqir, Said

    2016-01-01

    Le cancer est un problème majeur de santé public en Afrique. Les progrès réalisé dans le traitement des cancers ces dix dernières années est indéniable. L’émergence des thérapies ciblés en oncologie a permit de modifier l'histoire naturelle de certains cancers réputés de mauvais pronostic. En dépit de leurs efficacité, ces thérapeutiques pose un problème majeur de coût qui les rend inaccessible à la majorité des patients dans les pays en voie développement. Au Maroc, le cancer est reconnu comme a une affection de longue durée et les patients bénéficient de ce fait d'une couverture médicale totale. L'implication de la société civile a permis aussi d'améliorer la prise en charge ainsi qu'un accès plus élargi aux médicaments innovants pour les patients les plus démunis. PMID:27642392

  16. Effects of artificial dawn on subjective ratings of sleep inertia and dim light melatonin onset.

    PubMed

    Giménez, Marina C; Hessels, Martijn; van de Werken, Maan; de Vries, Bonnie; Beersma, Domien G M; Gordijn, Marijke C M

    2010-07-01

    The timing of work and social requirements has a negative impact on performance and well-being of a significant proportion of the population in our modern society due to a phenomenon known as social jetlag. During workdays, in the early morning, late chronotypes, in particular, suffer from a combination of a nonoptimal circadian phase and sleep deprivation. Sleep inertia, a transient period of lowered arousal after awakening, therefore, becomes more severe. In the present home study, the authors tested whether the use of an alarm clock with artificial dawn could reduce complaints of sleep inertia in people having difficulties in waking up early. The authors also examined whether these improvements were accompanied by a shift in the melatonin rhythm. Two studies were performed: Study 1: three conditions (0, 50, and 250 lux) and Study 2: two conditions (0 lux and self-selected dawn-light intensity). Each condition lasted 2 weeks. In both studies, the use of the artificial dawn resulted in a significant reduction of sleep inertia complaints. However, no significant shift in the onset of melatonin was observed after 2 weeks of using the artificial dawn of 250 lux or 50 lux compared to the control condition. A multilevel analysis revealed that only the presence of the artificial dawn, rather than shift in the dim light melatonin onset or timing of sleep offset, is related to the observed reduction of sleep inertia complaints. Mechanisms other than shift of circadian rhythms are needed to explain the positive results on sleep inertia of waking up with a dawn signal.

  17. Ambient lighting: setting international standards for the viewing of softcopy chest images

    NASA Astrophysics Data System (ADS)

    McEntee, Mark F.; Ryan, John; Evanoff, Micheal G.; Keeling, Aoife; Chakraborty, Dev; Manning, David; Brennan, Patrick C.

    2007-03-01

    Clinical radiological judgments are increasingly being made on softcopy LCD monitors. These monitors are found throughout the hospital environment in radiological reading rooms, outpatient clinics and wards. This means that ambient lighting where clinical judgments from images are made can vary widely. Inappropriate ambient lighting has several deleterious effects: monitor reflections reduce contrast; veiling glare adds brightness; dynamic range and detectability of low contrast objects is limited. Radiological images displayed on LCDs are more sensitive to the impact of inappropriate ambient lighting and with these devices problems described above are often more evident. The current work aims to provide data on optimum ambient lighting, based on lesions within chest images. The data provided may be used for the establishment of workable ambient lighting standards. Ambient lighting at 30cms from the monitor was set at 480 Lux (office lighting) 100 Lux (WHO recommendations), 40 Lux and <10 Lux. All monitors were calibrated to DICOM part 14 GSDF. Sixty radiologists were presented with 30 chest images, 15 images having simulated nodular lesions of varying subtlety and size. Lesions were positioned in accordance with typical clinical presentation and were validated radiologically. Each image was presented for 30 seconds and viewers were asked to identify and score any visualized lesion from 1-4 to indicate confidence level of detection. At the end of the session, sensitivity and specificity were calculated. Analysis of the data suggests that visualization of chest lesions is affected by inappropriate lighting with chest radiologists demonstrating greater ambient lighting dependency. JAFROC analyses are currently being performed.

  18. Does one hour of bright or short-wavelength filtered tablet screenlight have a meaningful effect on adolescents' pre-bedtime alertness, sleep, and daytime functioning?

    PubMed

    Heath, Melanie; Sutherland, Cate; Bartel, Kate; Gradisar, Michael; Williamson, Paul; Lovato, Nicole; Micic, Gorica

    2014-05-01

    Electronic media use is prevalent among adolescent populations, as is the frequency of sleeplessness. One mechanism proposed for technology affecting adolescents' sleep is the alerting effects from bright screens. Two explanations are provided. First, screens emit significant amounts of short-wavelength light (i.e. blue), which produces acute alertness and alters sleep timing. Second, later chronotypes are hypothesised to be hypersensitive to evening light. This study analysed the pre-sleep alertness (GO/NOGO task speed, accuracy; subjective sleepiness), sleep (sleep diary, polysomnography), and morning functioning of 16 healthy adolescents (M = 17.4 ± 1.9 yrs, 56% f) who used a bright tablet screen (80 lux), dim screen (1 lux) and a filtered short-wavelength screen (f.lux; 50 lux) for 1 hr before their usual bedtime in a within-subjects protocol. Chronotype was analysed as a continuous between-subjects factor; however, no significant interactions occurred. Significant effects occurred between bright and dim screens for GO/NOGO speed and accuracy. However, the magnitude of these differences was small (e.g. GO/NOGO speed = 23 ms, accuracy = 13%), suggesting minimal clinical significance. No significant effects were found for sleep onset latency, slow-rolling eye movements, or the number of SWS and REM minutes in the first two sleep cycles. Future independent studies are needed to test short (1 hr) vs longer (>2 hrs) screen usage to provide evidence for safe-to-harmful levels of screenlight exposure before adolescents' usual bedtime.

  19. Estimation of effective day length at any light intensity using solar radiation data.

    PubMed

    Yokoya, Masana; Shimizu, Hideyasu

    2011-11-01

    The influence of day length on living creatures differs with the photosensitivity of the creature; however, the possible sunshine duration (N(0)) might be an inadequate index of the photoperiod for creatures with low light sensitivity. To address this issue, the authors tried to estimate the effective day length, i.e., the duration of the photoperiod that exceeds a certain threshold of light intensity. Continual global solar radiation observation data were gathered from the baseline surface radiation network (BSRN) of 18 sites from 2004 to 2007 and were converted to illuminance data using a luminous efficiency model. The monthly average of daily photoperiods exceeding each defined intensity (1 lx, 300 lx, … 20,000 lx) were calculated [defined as Ne(() (lux) ())]. The relationships between the monthly average of global solar radiation (Rs), N(0), and Ne(() (lux) ()) were investigated. At low light intensity (<500 lx), Ne(() (lux) ()) were almost the same as N(0). At high light intensity (>10,000 lx), Ne(() (lux) ()) and Rs showed a logarithmic relationship. Using these relationships, empirical models were derived to estimate the effective day length at different light intensities. According to the validation of the model, the effective day length for any light intensity could be estimated with an accuracy of less than 11% of the mean absolute percentage error (MAPE) in the estimation of the monthly base photoperiod. Recently, a number of studies have provided support for a link between day length and some diseases. Our results will be useful in further assessing the relationships between day length and these diseases.

  20. The Completely Sequenced Plasmid pEST4011 Contains a Novel IncP1 Backbone and a Catabolic Transposon Harboring tfd Genes for 2,4-Dichlorophenoxyacetic Acid Degradation

    PubMed Central

    Vedler, Eve; Vahter, Merle; Heinaru, Ain

    2004-01-01

    The herbicide 2,4-dichlorophenoxyacetic acid (2,4-D)-degrading bacterium Achromobacter xylosoxidans subsp. denitrificans strain EST4002 contains plasmid pEST4011. This plasmid ensures its host a stable 2,4-D+ phenotype. We determined the complete 76,958-bp nucleotide sequence of pEST4011. This plasmid is a deletion and duplication derivative of pD2M4, the 95-kb highly unstable laboratory ancestor of pEST4011, and was self-generated during different laboratory manipulations performed to increase the stability of the 2,4-D+ phenotype of the original strain, strain D2M4(pD2M4). The 47,935-bp catabolic region of pEST4011 forms a transposon-like structure with identical copies of the hybrid insertion element IS1071::IS1471 at the two ends. The catabolic regions of pEST4011 and pJP4, the best-studied 2,4-D-degradative plasmid, both contain homologous, tfd-like genes for complete 2,4-D degradation, but they have little sequence similarity other than that. The backbone genes of pEST4011 are most similar to the corresponding genes of broad-host-range self-transmissible IncP1 plasmids. The backbones of the other three IncP1 catabolic plasmids that have been sequenced (the 2,4-D-degradative plasmid pJP4, the haloacetate-catabolic plasmid pUO1, and the atrazine-catabolic plasmid pADP-1) are nearly identical to the backbone of R751, the archetype plasmid of the IncP1 β subgroup. We show that despite the overall similarity in plasmid organization, the pEST4011 backbone is sufficiently different (51 to 86% amino acid sequence identity between individual backbone genes) from the backbones of members of the three IncP1 subgroups (the α, β, and γ subgroups) that it belongs to a new IncP1subgroup, the δ subgroup. This conclusion was also supported by a phylogenetic analysis of the trfA2, korA, and traG gene products of different IncP1 plasmids. PMID:15489427